Devices as print media. Types of storage media, their classification and characteristics

What is the most precise definition of the term "printer"? A computer printer, or simply a "printer" (from the English Print - "print") - a device for obtaining a "hard copy" (printing on various types of media, mainly paper) of texts, images, graphics - in other words, documents that were originally stored in a digital form. Initially, a computer printer meant a peripheral device connected to a PC through one of the widely used interfaces (including wireless or network). This definition is now somewhat outdated. Since, firstly, there are many ways to output data to a printer without the "mediation" of a computer - for example, directly from flash cards, digital video and photo cameras, built-in fax modems. Secondly, a fairly common class of MFPs has appeared, which are a combination of a printer, scanner, other input devices, plus a built-in "mini-computer" for pre-print data processing. What does the abbreviation "MF" mean? The MFP is a multifunctional device. In relation to devices for creating a "hard copy" of documents, this abbreviation, as a rule, means a printer that is structurally, logically and programmatically integrated into one whole with one or more data processing devices and auxiliary solutions. A classic MFP is a printer combined with a scanner, resulting in a device for printing, scanning and copying in one housing. Adding a Fax Modem and Interface Board telephone line turns such a device into an office MFP with a fax function. Modern MFPs, as a rule, are universal - they have several interfaces at once, slots for flash cards, built-in memory for storing data, etc. What does the abbreviation SOHO mean in relation to printers? The abbreviation SOHO - Small Office, Home Office, that is, "Small or home office", means that the printer or MFP of this class is designed to meet the needs of a group of workers in a small office or home needs for printing documents. Unlike enterprise print devices, SOHO class printers tend to have moderate performance and a limited set of relevant interfaces. It is these printers that are most often called "personal", or simply "desktop". What determines the maximum print speed of the printer, why is it sometimes less than that declared by the manufacturer? The maximum print speed listed in official specifications usually reflects the capabilities of the printer's printing mechanism. In practice, the speed depends on many factors, such as the type of interface, the quality of the driver used - even the type of document or its content. For GDI printers, the speed of printing can also be significantly affected by the performance of the computer. Also quite often manufacturers as top speed prints of one or another model indicate the conditions for the output of a document with approximately 5% page filling with text; much less often - with 20% filling with a raster and / or text. In practice, one distinguishes constant speed printing and printing speed, taking into account the output of the first page, sometimes the printing of the first page is given as a separate characteristic, since the longer time of its output depends on a number of indirect reasons; for example, in laser printers - from heating the "stove". What is a "GDI printer"? Processing of incoming print data and converting them into a form acceptable for the printing mechanism in any, even the simplest printer, is carried out using the built-in processor. In principle, it can be called a "printer controller", but that's not the point. Any built-in processor (controller) of the printer is necessarily controlled using some command description language. Such languages ​​include, for example, Postscript, PCL, ESC/P, HPGL, Lineprinter, Xerox XES/UDK, Luminous LN02Plus and many others. Another thing is the GDI printer. In fact, GDI, or Graphic Device Interface, is nothing more than a library of certain functions. operating system Windows to display information to graphic peripherals such as displays or printers. Thus, the processor of a "GDI printer" is exactly the case when the definition of "controller" is more appropriate in relation to it. Unlike printers with a powerful built-in processor, the GDI printer controller only outputs information to the printer's buffer memory. The information received by the print program is a page description that reproduces graphic primitives already prepared for printing - lines, text, etc., for the processing of which GDI functions are called. The printer driver for a particular version of Windows translates this information into the printer's internal language. In other words, a decent part of the work of preparing an image for printing in the case of the GDI model falls not on the printer, but on the computer. The advantages of such a "work organization" are enormous: you do not have to overpay for a fairly expensive printer electronics; for PC owners of even average power, the issue of a small additional load on the CPU is simply invisible. True, there are also disadvantages, although in our time they are rather arbitrary, if we are not talking about working from a platform other than Windows. Well, who now, for example, needs printing from DOS? Previously, some models also had difficulty using as a network printer in mixed networks. In practice, it is not uncommon for different manufacturers to specify their own varieties of the GDI system as the control language in the printer specifications. For example, for Samsung printers, this is SPL, or SPL-Color - Samsung Printing Language. What is DPI? DPI, or Dots per inch (dots per inch) is an established measure of print resolution, which means the number of individual dots that are linearly placed during printing on a segment of one inch, or 25.4 mm. For inkjet printers, it refers to the number of ink droplets; for laser printers, it refers to the number of distinguishable toner particles sintered under the influence of electrographic transfer.

Of course, the more dots per inch the printer can accommodate, the better the print quality will be. In other words, a 1200 dpi printer will produce better detail than a 600 dpi printer. Dot-matrix printers, where dots are formed by imprinting ink from an ink ribbon under the influence of needles, have the lowest resolution. In practice, vertical and horizontal (linear) print resolutions are also distinguished. Sometimes the vertical resolution differs significantly due to the use of motors with different media shift pitches. What is "LPI"? LPI, or Lines per inch (lines per inch) - print resolution in halftone systems, means how close the lines in the halftone grid can be printed when printed. More a high resolution LPI means a more detailed print result with greater clarity. As a rule, this characteristic is used when working with printing equipment, where when printing magazines and newspapers, they are guided by a system of halftones.

What are the main types of printing technologies called and what are they?

Laser printers come in both monochrome and color. A variety of laser printers can be considered light-emitting diode (LED) printers. LED and laser technology digital printing similar to the use of electrography, however, if in the first case a laser unit is used as a light source to form a surface charge on a photosensitive drum or tape, then in an LED printer there is a line (or several - if we are talking about a color model) of thousands of LEDs that illuminate the surface through focusing lenses photosensitive drum/tape immediately over the entire width.

Despite the constant rivalry between these very similar varieties of "laser" technologies, it is not so easy to give unambiguous leadership in any advantage to any of them, because, as always, it is not the principle of printing that is more important, but the quality of implementation at this stage of technology development. inkjet printing- the principle of printing, in which the imprint on the media is formed by ink drops "shot" from the nozzles of the print head. As a rule, the size of ink droplets of modern printers is measured in units of picoliters (10 -12, one trillionth of a liter), respectively, the print resolution with this method of imprint formation is thousands of dots per inch.

The printheads of modern inkjet printers have tens and hundreds of nozzles; The "matrix" arrangement of the nozzles increases the speed of printing and better blending of the colors of the miniature ink droplets for more realistic results.

Most modern inkjet printers are color models, that is, they print with ink of several colors at once, with rare exceptions - for example, monochrome ultra-fast inkjet models are very popular in the banking sector. There are also "inkjet photo printers" - as a rule, models with a large number of different colors of ink, up to ten, the ink of which reproduces the color photorealistic gamut on a special photo paper for inkjet printing in a better quality. A typical inkjet printer is generally inexpensive to manufacture, and other benefits include significantly better photo quality than a typical laser printer. The disadvantages of inkjet printing include the fact that often the cost of a printer is comparable to the price of a new set of ink cartridges. Sometimes users resort to buying alternative cartridges or CISS systems, which does not always have a favorable effect on print quality and the duration of storage of results. Inkjet printing is much more demanding on media, besides, ink, if the printer is not used for a long time, tends to dry out, which sometimes leads to the need to replace the print head. In general, modern inkjet printing significantly differs from the samples of a decade and even five years ago: the printing speed has been significantly increased, the cost of a print has been reduced, many issues have been resolved with the use of various types of media and ink drying. Solid ink printing- technology for transferring molten wax ink through holes whose diameter is less than the thickness of a human hair, from stationary printheads to a rotating drum, from which the image is then transferred to the media.

The basis of technology - special pigment ink, capable of maintaining a solid state at room temperature, melting at temperatures above 60 ° C and instantly solidifying with slight cooling.

The advantages of the technology are the reproduction of bright colors on almost any surface, excellent coverage of the sRGB gamut by CMYK ink; simple design of the color printing mechanism that transfers solid ink in one pass of the media; high speed. There is also a drawback - high ink consumption during a "cold start" for preparation and calibration. sublimation printing. Sublimation (Dye-sublimation) printers in the process of forming a print use the heating of special ribbons, as a result of which the color dye is transferred to the media. The most common sublimation printers for working with one color - usually they are used to print on media such as plastic cards, paper or canvas. However, color models are also common, where several ribbons with dyes of several colors are used for transfer. The advantages of sublimation printing include excellent quality of color reproduction; moreover, using ribbons with the most exotic dye colors, such as silver, gold or neon shades, you can get unique color combinations when decorating the same business cards. The disadvantages of sublimation printers include a low print speed and, as a rule, a rather high cost of a print. Thermal printing, thermal transfer- the principle of printing, which uses a special carrier that changes its color after heating. A typical example of such a printer is a fax on thermal paper, where the special media roller, after local heating, is able to convey the "fax" character of the original. A typical use for thermal printing is the faxes mentioned above (in recent times they are being vigorously replaced by plain paper laser faxes), cash registers, ATM terminal printers. The disadvantages of the technology are obvious - low resolution and the need to use a special medium. Pros - none Supplies other than the carrier. Perhaps, within the framework of this material, we will confine ourselves to details only about the above methods of printing, as they are really relevant today. In fact, there are many other ways to transfer information to paper in the world. For example, plotters that draw an image using special ink pens or felt-tip pens; dot-matrix printers that “beat off” letters or pseudographics with their needles on paper through an ink ribbon; ancient teletypes and "chamomile" printers that print characters in ready-made characters. As well as digital minilabs, linear, electrolytic printers and other types of exotics that are hardly relevant in a modern home or office.

What is CMYK?

To add realism to photographs by improving halftone printing, manufacturers of inkjet photo printers supplement the CMYK color model with additional ink cartridges with additional "transitional" shades. It can be "light magenta", "photo black", neutral grey", turquoise" and other shades of ink, depending on the implementation of the technology and the marketing fantasy of the manufacturer.

What is SNPC?

What are the main characteristics of print media?

• Density (g/m², grams per square meter). For office printing, the optimal density is within 80 g / m² - 130 g / m²
• Whiteness - determines the degree of reflection of light from the sheet, measured as a percentage
• Media contaminants - internal (chemicals, adhesives) from manufacturing and external (dust) e.g. due to static
• Acid / alkaline reaction - during an acid reaction, the carrier quickly ages, turns yellow, becomes brittle; in the case of alkaline, it has better reflectivity. Sometimes gluing layers is practiced to slow down the penetration of liquids (ink, dyes) into the sheet, to fix paper fibers
• Moisture content - 4.5% moisture is standard
• Rigidity is a parameter that varies depending on the arrangement of the fibers and is always higher in the direction across the fibers.
• Smoothness
• Porosity - affects both feed reliability and print quality
• Paper caliber (thickness) - completely depends on the density and subsequent calendering (pressing), after which the paper becomes thinner, smoother. A higher caliber indicates a stiffer grade of paper.
• Electrical conductivity - a parameter due to which, in wet conditions, image gaps occur, and in dry conditions, a background appears and sometimes sheets stick together.
• Heat resistance - toner fixing laser printer involves heating the paper up to +100°C and above. Non-specialized paper then becomes brittle and sometimes turns yellow
• Friction - a parameter that determines the ease of separation of sheets in a pack from each other
• Opacity is an important parameter for duplex printing
• Edge quality after cutting - with poor cut quality, dust settles on the print path and accelerates its wear

A print medium intended for printing with water-containing ink, which includes a coloring matter, consists of a paper base and an ink-receiving layer formed on its surface. The ink-receiving layer includes a porous layer containing an inorganic pigment, as well as a substance that reacts with the coloring matter of the ink. The ink receiving layer has properties such that a drop of distilled water with a volume of 4 μl falling on the surface of said layer is absorbed in the first stage of absorption with the first absorption rate V1 (μL/sec) within one second after falling, in the second stage of absorption from the second uptake rate V2 (μl/sec) after the first uptake stage and in the third uptake stage following the second uptake stage with a third uptake rate V3 (µl/s). In this case, the second absorption rate V2 (μl/sec) is greater than 0.01 (μl/sec) and less than 0.32 (μl/sec). The absorption of a drop at all, from the first to the third, stages of absorption satisfies the relations: 0

The field of technology to which the invention belongs

The present invention relates to a print medium for water-based ink, where the print medium includes a paper base and an ink-receiving layer, and to a method for determining absorption parameters of this print medium ink. In particular, the present invention relates to a matte-type recording medium for aqueous ink, where the recording medium has a relatively low gloss and is suitable for inkjet printing.

State of the art

In recent years, in the field of offset and letterpress printing, printing using water-based ink to produce print copies at high speed has been realized, which has increased the importance of the parameters of the printing medium. In particular, with the advancement of inkjet printers, it has become possible to obtain sharp images and provide superior print quality. At the same time, there is a need for such a print medium, the improved properties of which would allow further improvement in print quality. Various printing media have been developed to meet this need.

On the other hand, the use of water-based inkjet printers has become popular, such printers are also used in advertising, such as poster printing. When used for these purposes, not only print parameters such as high image quality and high print density are important, but also the preservation of image clarity during long-term use of information materials or during storage. Hitherto, water-based dye inks having excellent color reproduction have been used as inkjet inks. However, as a rule, water-based dye inks tend to fade when exposed to light, losing clarity over time. Thus, water-based dye inks were not suitable for printing long-term use or long-term storage of materials. The solution to this problem is accompanied by an increase in the number of printers and plotters that work with water-based inks with pigments that have excellent light fastness.

However, the performance of the pigmented aqueous ink differs from that of the dye-based aqueous ink, for example, due to the fact that the pigments used in the pigmented aqueous ink are particulates. Consequently, print media was designed exclusively for use with one of these two types of ink, and there is hardly any print media that is suitable for use with both inks.

In general, the development of a pigment ink carrier is aimed at improving its ink absorption capacity, while a dye ink carrier needs a lower ink absorption capacity than a pigment ink carrier, instead a suitable fixative is selected. ink. Thus, water-based dye ink and water-based pigment ink have opposite characteristics, so that if the wrong combination of ink and printing medium is used, poor-quality printed products with inadequate optical density or image sharpness will be obtained. For example, when the pigmented ink is printed on a conventional water-based dye ink recording medium, the pigmented ink is not absorbed by the medium, and a phenomenon such as print unevenness or cracking occurs, which creates problems in use of the printed product.

According to a rough classification, the printing media for dye-based water-based ink is divided into glossy, high gloss, matt, low gloss, and uncoated paper with a texture close to that of paper without wood pulp. Glossy print media is divided into media that use resin-coated paper as the base of photo paper containing silver salts, and that use uncoated paper. Both types are characterized by a narrow fine particle diameter distribution and in that the coating layer can be formed by a pigment providing a permeability, thus absorbency and gloss can be combined. In the case of printing on a glossy media of one of these types, ink absorption is slow because the ink-receiving layer on the media is formed by fine pigment, therefore, the printing speed is reduced to that of the printer, thereby suppressing the effect of loss of sharpness in the image. As a result, the print speed is slow and the printer's performance is not fully utilized.

Especially in the case of a matte recording medium, which has been developed mainly to improve its ink absorption capacity, a pigment with a much larger particle diameter than the pigment particles used in the glossy type medium is used, resulting in a low gloss degree. There is known such a recording medium with even more improved ink absorption capacity, in which the surface of the paper substrate is treated to improve the solvent permeability, thereby accelerating the flow of liquid into the boundary region between the ink-receiving layer and the paper substrate. In any case, since the matte recording medium has a large pigment particle diameter, its ink absorption rate is higher than that of the glossy type, and it is said that a high printer speed can be selected when printing on this medium. However, recently, with the spread of digital cameras, printing of full-color images began to be carried out not only on glossy, but also on matte media. Therefore, compared with printing single-color images, the amount of ink per unit area is increased, making it necessary to further improve the ink-absorbing capacity of the media. However, when trying to meet these requirements, there is a problem with the perception of color and the loss of sharpness of different color shades.

As mentioned above, in the current situation where there is not yet a print media suitable for both water-based dye ink and water-based pigment ink, which require different absorption properties, it can be effective to improve the properties of an existing print media by creating several ink-receiving layers. , for example, as described in Patent Literature 1 or 2. However, no recording medium has yet been proposed with absorbent properties satisfactory for both water-based dye ink and water-based pigment ink.

Objectives of the invention

The purpose of the present invention is to analyze conventional water-based ink media, find out the reason that prevents good quality images from being obtained, establish the relationship between the paper substrate and the ink-receiving layer, where the relationship is considered to be difficult to determine qualitatively or quantitatively, and thereby provide a printed water-based ink media that allows you to get the desired image without a lot of pre-sampling. Another object of the present invention is to provide a recording medium having optimum printability with aqueous dye ink and aqueous pigment ink, which was not achievable in the prior art, as well as a method for determining the printability with aqueous ink without pre-printing.

More specifically, the first object of the present invention is to provide a new printing medium for printing with water-based dye ink and water-based pigment ink, which print medium guarantees the color reproduction and density uniformity of the "monolithic image".

The second object of the present invention is to provide an easy-to-understand measure of the ability of a novel water-based ink carrier to absorb ink.

A third object of the present invention is to provide a print medium for water-based ink having the unique ability to absorb liquid necessary to produce a desired image.

The fourth object of the present invention is to provide a recording medium for aqueous ink capable of producing a clear image even if the weight of the paper base used therein increases.

The fifth object of the present invention is to provide a matte print medium for aqueous ink capable of obtaining an image that conveys a sense of depth, which has not yet been achieved.

The present invention achieves at least one of these objectives. However, as will become clear from the following description, the present invention also contributes to solving other problems.

The essence of the invention

In the course of the work aimed at achieving these goals, the authors of the present invention, using an optical electron microscope, studied the effect on the ink absorption parameters of a conventional paper base, an ink receptive layer, and a boundary region between the paper base and an ink receptive layer. However, until now it has been difficult to identify this relationship either qualitatively or quantitatively. In connection with the method for clearly displaying the parameters of conventional printing media, the inventors of the present invention noted that the main component of water-based ink is pure water, so the behavior of pure water during its absorption by a recording medium was investigated. Real inkjet printing uses ink droplets ranging from 2 to 8 picolitres. In view of this fact, the inventors of the present invention measured the absorption parameters of one microliter of pure water, however, it was not possible to determine the behavior of pure water due to too rapid absorption. In the course of numerous experiments carried out since then, the authors of the present invention measured the absorption parameters of four microliters of pure water, which made it possible to determine the parameters of conventional printing media.

The results of determination of the absorption parameters of the working surface of conventional water-based ink media are shown in Table 1 (J, K, L and M), and are also shown in Fig. 1 (J, K, L and M represent the absorption parameters of conventional water-based ink media , the abscissa shows the amount of absorbed liquid, the ordinate shows the time after the fall of the drop). As can be seen from Fig. 1, conventional print media, designated J and K, are characterized by having a long period of low liquid absorption, due to which, as a result, a significant excess of spilled ink distorts the image, which facts have been found to be interconnected. It is believed that the mechanism of this phenomenon is as follows. The recording medium for aqueous ink according to the present invention is a three-layer structure in which there is a high-density boundary region acting as a filter at the boundary between the base paper and the ink-receiving layer. On the other hand, conventional recording media, denoted as J and K, have a two-layer structure in which the base paper and the ink-receiving layer are directly connected to each other; it is believed that these absorption features arise from the fact that filtering through the interface between the paper substrate and the ink-receiving layer is too difficult.

The print medium, designated M, absorbs ink very quickly, a fact consistent with the observed decrease in image optical density. It is believed that the mechanism of this phenomenon can be explained as the unlikely presence of a boundary region that acts as a filter on the interface, since the amount of binder contained in the ink-receptive layer is small and, therefore, a single layer structure is predominant, although the media in question consists of two layers - a paper base and an ink-receiving layer. This is believed to be the reason for the existing absorption features.

The printing medium designated as L is intermediate between the two cases described, has better parameters than the J and K media, however, is characterized by insufficient dot gain and density, which facts have been found to be interconnected. It is believed that the mechanism of this phenomenon is as follows. The ink receptive layer with a small amount of binder is dried at a low temperature for a long time, whereby the binder penetrates the entire base paper, and the filter-function boundary region formed at the interface of the base paper and the ink receptive layer has a low density. Therefore, a single layer structure is predominant, although this print medium actually consists of two layers. This is believed to be the reason for the existing absorption features.

Thus, the parameters set in the context of the present invention are indicative, both quantitatively and qualitatively, of the properties of conventional print media. Based on the obtained data, the authors of the present invention investigated the parameters of the printing medium, which would satisfy the objectives of the present invention, resulting in the present invention.

The detection method according to the present invention is that a drop of distilled water with a volume of 4 μl is dropped onto the surface of the ink-receiving layer of a recording medium for water-based ink, which recording medium consists of a paper base and an ink-receiving layer, and the ink-receiving layer is on the surface of the paper. bases and contains amorphous silicon oxide, an adhesive and a substance that reacts with the coloring matter of the ink; the drop is absorbed in the first absorption stage with the first absorption rate V1 (µl/sec) within one second after falling, in the second absorption stage following the first absorption stage with the second absorption rate V2 (μl/sec) and in the third absorption stage, following the second uptake stage, with a third uptake rate V3 (µl/sec). Then, the absorption parameters of the printing medium are measured, provided that the inflection point between the first absorption stage V1 and the second absorption stage V2 is a, the inflection point between the second absorption stage V2 and the third absorption stage V3 is b, the end point of the third absorption stage V3 is c, the amounts of liquid absorbed at the inflection points a, b and c are qa, qb and qc, and the time to reach these points is ta, tb and tc.

The uptake rates V1, V2, and V3 discussed herein roughly correspond to straight lines in the uptake stages, derived from the measured values, connecting the inflection points to the end point.

The inflection points discussed herein correspond to the point at which the absorption rate changes from V1 to V2 and the point at which the absorption rate changes from V2 to V3. In the case where the change in speed from V1 to V2 and from V2 to V3 occurs smoothly in a certain range of change, draw, for example, a line from the point of intersection of the continuation of the straight lines corresponding to V1 and V2, vertically to the approximate curve corresponding to the change range, and the point their intersection is the inflection point.

In general, it is believed that in order to prevent warping and the like. paper substrate, which can occur during the application of the coating material, a paper substrate with a high Stöckigt sizing should be used. The inventors of the present invention, on the contrary, tried to use a paper base with a low Steckigt sizing ratio and, in addition, with regard to the pH of the paper base, they tried to use a paper with an acidic pH, although a low fading neutral paper is usually used.

In any case, believing that the ink-receiving layer or the base material itself is important in terms of the quality of the media, the inventors of the present invention investigated the properties of each of these constituents. As a result of extensive research, it was found that it is not the influence of each of the components that is dominant, but the "filtering function" of the boundary region between the ink-receiving layer and the paper base.

Figures 2 and 3 show absorption parameters of conventional water-based ink media and water-based ink media according to the present invention.

The letters A, B, C, D, E, F, G, H and I in figure 2 denote the measurement results presented in graphical form, further given in table 1, and the letters N, O, P, Q, R, S, T, U, V and W in FIG. 3 are the measurement results shown in graphical form, which are further summarized in Table 3, in both cases being the absorption parameters of the print media for the aqueous ink according to the present invention.

As can be seen from Tables 1-4 and Figures 2 and 3, the absorption parameters of the aqueous ink media of the present invention differ markedly from those of conventional aqueous ink media. In addition, by comparing the actual printed product with the printed product made on the carriers of the present invention, the inventors found that in the latter case, the print quality is higher, and also found that the absorption parameters shown in figures 1-3 are consistent with those actually obtained. images.

As a result of determining the absorption parameters using drops of distilled water with a volume of 1 to 7 μl, the inventors found that using a drop of 4 μl allows you to most clearly establish the difference in absorption parameters.

After intensively researching the properties of all constituents of the recording medium, including the ink receiving layer and the base paper, the inventors of the present invention found that the absorption rate of the recording medium for water-based ink must satisfy certain conditions, and made the present invention related to both the recording medium for water-based ink and and a method for determining absorption parameters of a recording medium for aqueous ink, as will be described later.

The present invention is as follows:

(1) A recording medium for water-based ink, comprising a paper base and an ink receiving layer formed on the surface of the paper base, where the ink receiving layer is a porous layer containing an inorganic pigment, and also containing a substance reactive with the coloring matter of the ink, where on the printed media, printing is carried out with water-containing ink, which includes the coloring matter of the ink; characterized in that a drop of distilled water with a volume of 4 μl, which has fallen on the surface of the ink-receiving layer, is absorbed in the first stage of absorption with the first absorption rate V1 (μl / sec) within one second after falling, in the second stage of absorption with the second absorption rate V2 ( µl/sec) for at least 2 seconds after the first uptake stage and in the third uptake stage following the second uptake stage with a third uptake rate V3 (µl/s), with droplet uptake at all, from first to third, the stages of absorption satisfies the following relationship:

while the second absorption rate V2 (µl/s) is greater than 0.01 (µl/s) and less than 0.32 (µl/s), provided that the inflection point between the first and second absorption stages is a, the inflection point between the second and the third absorption stage is b, the end point of the third absorption stage is c, the amounts of liquid absorbed at points a, b and c are qa, qb and qc, respectively, the time to reach these points is ta, tb and tc, respectively, the amount of liquid absorbed liquid qa at the inflection point a is not less than 1.3 µl and less than 2.0 µl, the amount of absorbed liquid qb at point b is not less than 2.0 µl and less than 2.5 µl.

(2) The recording medium for water-based ink according to claim 1, wherein the inflection point a corresponds to a time of 0.5 seconds after the drop has fallen.

(3) The recording medium for water-based ink according to claim 1, wherein the amount of liquid (qb-qa) absorbed in the second absorption step is not less than 0.3 µl and not more than 1.4 µl.

(4) The recording medium for water-based ink according to claim 1, wherein the amount of liquid (qb-qa) absorbed in the second absorption step is not less than 0.5 µl and not more than 1.0 µl.

(5) The recording medium for water-based ink according to claim 1, wherein the amount of absorbed liquid qa at the inflection point a is not less than 1.5 μl.

(6) The recording medium for water-based ink according to claim 5, wherein the weight of the recording medium is not less than 180 g/m 2 and not more than 300 g/m 2 , and the inflection point b occurs within 8 seconds after the drop.

(7) Printing medium for water-based ink according to any one of paragraphs. 1-6, in which the paper base is characterized by a Steckigt sizing degree of at least 5 seconds and at most 50 seconds.

(8) Printing medium for water-based ink according to any one of paragraphs. 1-6, in which the ink-receiving layer has a pH B that satisfies the following relationship:

5<рН В ≤7

(9) The water-based ink recording medium according to claim 8, wherein the base paper has a pH of A and the ink receiving layer has a pH of B, satisfying the following relationship:

1<(рН В -рН А)<4

(10) A print medium for aqueous ink according to any one of paragraphs. 1-6, in which the second uptake rate V2 (μl/sec) is greater than 0.05 (μl/sec) and less than 0.23 (μl/sec).

(11) Printing medium for water-based ink according to any one of paragraphs. 1-6, in which the second uptake rate V2 (μl/sec) is greater than 0.12 (μl/sec) and less than 0.23 (μl/sec).

(12) A recording medium for water-based ink, comprising a paper base, where the paper base has a Steckigt sizing degree of not less than 5 seconds and not more than 50 seconds, and an ink receiving layer formed on the surface of the paper base, where the ink receiving layer contains amorphous silicon oxide , an adhesive and a substance that reacts with the coloring matter of the ink, and is characterized in that a drop of distilled water with a volume of 4 μl, which has fallen on the surface of the ink-receiving layer, is absorbed in the first stage of absorption at the first absorption rate V1 (μl/sec) for one seconds after the fall, in the second uptake stage at a second uptake rate V2 (µl/sec) for at least 2 seconds after the first uptake stage, and in the third uptake stage following the second uptake stage at a third uptake rate V3 (µl /sec) for 8 seconds after falling, while the absorption of the drop in these, from the first to the third, stages of absorption satisfies the following relation:

0

while the second absorption rate V2 (µl/s) is greater than 0.01 (µl/s) and less than 0.32 (µl/s), provided that the inflection point between the first and second absorption stages is a, the inflection point between the second and the third absorption stage is b, the end point of the third absorption stage is c, the amounts of liquid absorbed at points a, b and c are qa, qb and qc, respectively, the time to reach points a, b and c is ta, tb and tc, respectively, the amount of absorbed liquid qa at the inflection point a is not less than 1.5 µl and not more than 2.0 µl, the amount of liquid (qb-qa) absorbed in the second stage of absorption is not less than 0.3 µl and not more than 1.0 µl.

(13) The water-based ink recording medium according to claim 12, wherein the ink-receiving layer has a pH of B that satisfies the following relationship:

5<рН В ≤7,

the paper base has a pH of A, and the ink receiving layer has a pH of B, satisfying the following relationship:

1<(рН В -рН А)<4,

(14) The recording medium for water-based ink according to claim 12 or 13, wherein the second absorption rate V2 (μl/sec) is greater than 0.12 (μl/sec) and less than 0.23 (μl/sec).

(15) A recording medium for water-based ink, which is printed with water-based ink containing an anionic colorant, on the surface of which the recording medium has an ink-receiving layer, where the ink-receiving layer is a porous layer containing an inorganic pigment and a substance , which reacts with the coloring matter of the ink; characterized in that a drop of distilled water with a volume of 4 μl, which has fallen on the surface of the ink-receiving layer, is absorbed in the first stage of absorption with the first absorption rate V1 (μl / sec) within one second after falling, in the second stage of absorption with the second absorption rate V2 ( μl/sec) for at least 2 seconds after the first absorption stage and in the third absorption stage following the second absorption stage, with a third absorption rate V3 (μl/sec), while the absorption of the drop on these, from the first to the third, absorption stages satisfies the following relation:

while the second absorption rate V2 (µl/s) is greater than 0.01 (µl/s) and less than 0.32 (µl/s), provided that the inflection point between the first and second absorption stages is a, the inflection point between the second and the third absorption stage is b, the end point of the third absorption stage is c, the amounts of liquid absorbed at points a, b and c are qa, qb and qc, respectively, the time to reach these points is ta, tb and tc, respectively, the amount of liquid absorbed liquid qa at the inflection point a is not less than 1.3 µl and not more than 2.0 µl, the amount of liquid (qb-qa) absorbed in the second stage of absorption is not less than 0.3 µl and not more than 1.0 µl.

(16) The recording medium for water-based ink according to claim 15, wherein the second absorption rate V2 (μl/sec) is greater than 0.05 (μl/sec) and less than 0.23 (μl/sec).

(17) The recording medium for water-based ink according to claim 16, wherein the paper base has a Steckigt sizing degree of at least 5 seconds and at most 50 seconds.

(18) A recording medium for water-based ink, comprising a paper base and an ink receiving layer formed on the surface of the paper base, where the ink receiving layer contains amorphous silicon oxide, an adhesive, and a colorant reactive agent of the ink, and characterized in that the drop 4 μl of distilled water that has fallen on the surface of the ink-receiving layer is absorbed in the first stage of absorption at the first absorption rate V1 (μL/sec) within one second after falling, in the second stage of absorption at the second absorption rate V2 (μL/sec) in for at least 2 seconds after the first uptake stage and in the third uptake stage following the second uptake stage, with a third uptake rate V3 (μl/sec), while the droplet uptake in these first through third uptake stages satisfies the following ratio:

while the second absorption rate V2 (µl/s) is greater than 0.01 (µl/s) and less than 0.32 (µl/s), provided that the inflection point between the first and second absorption stages is a, the inflection point between the second and the third absorption stage is b, the end point of the third absorption stage is c, the amounts of liquid absorbed at points a, b and c are qa, qb and qc, respectively, the time to reach these points is ta, tb and tc, respectively, the amount of liquid absorbed liquid qa at inflection point a is not less than 1.3 µl and less than 2.0 µl, the amount of absorbed liquid qb at inflection point b is greater than the amount of liquid qa absorbed in the first stage and less than 2.5 µl, the amount of liquid (qb-qa ) absorbed in the second stage of absorption, not less than 0.3 µl and not more than 1.4 µl.

(19) The water-based ink recording medium according to claim 18, wherein the amount of liquid (qb-qa) absorbed in the second absorption step is not less than 0.38 µl and not more than 1.0 µl.

(20) The recording medium for water-based ink according to claim 19, wherein the amount of absorbed liquid qa at the inflection point a is not less than 1.5 μl.

(21) The recording medium for water-based ink according to claim 18, wherein the second absorption step takes place not earlier than 2.0 sec and not later than 13.5 sec after the drop.

(22) The recording medium for water-based ink according to claim 21, wherein the time tc in the third absorption stage is up to 14.1 seconds after the drop has fallen.

(23) The recording medium for the water-based ink according to claim 20, wherein the second absorption stage takes up to 6.1 seconds after the drop, and the time tc to the end point of the third absorption stage is up to 8 seconds after the drop.

(24) The recording medium for the water-based ink according to claim 19, wherein the second absorption step takes place within or 9.5 seconds after the drop, and the time tc to the end point of the third absorption stage is up to 14.5 seconds after the drop .

(25) Printing medium for water-based ink according to any one of paragraphs. 17-24, in which the second uptake rate V2 (μl/sec) is greater than 0.05 (μl/sec) and less than 0.23 (μl/sec).

(26) The recording medium for water-based ink according to claim 23, wherein the second absorption rate V2 (μl/sec) is greater than 0.12 (μl/sec) and less than 0.23 (μl/sec).

(27) The recording medium for water-based ink according to claim 24, wherein the second absorption rate is greater than 0.05 (μl/sec) and less than 0.09 (μl/sec).

(28) A method for determining absorption parameters of a recording medium for water-based ink, wherein the recording medium includes a paper substrate and an ink sensing layer formed on the surface of the paper substrate, wherein the ink sensing layer contains amorphous silicon oxide, an adhesive, and a colorant-reactive agent of the ink , which method involves determining that:

a drop of distilled water with a volume of 4 μl falling on the surface of the ink-receiving layer of a recording medium for water-based ink is absorbed in the first stage of absorption at the first absorption rate V1 (μL/sec) within one second after falling, in the second stage of absorption at the second absorption rate V2 (μl/sec) for at least 2 seconds after the first absorption stage and in the third absorption stage following the second absorption stage, with a third absorption rate V3 (μl/sec);

that the second uptake rate V2 (μl/sec) is greater than 0.01 (μl/sec) and less than 0.32 (μl/sec); and

determination of inflection points a between the first and second absorption stages, b between the second and third absorption stages and the end point of the third absorption stage c, provided that the amounts of liquid absorbed at points a, b and c are equal to qa, qb and qc, respectively, time before reaching points a, b and c is ta, tb and tc, respectively, the amount of absorbed liquid qa at the first stage of absorption is not less than 1 μl and less than 2.0 μl, the amount of absorbed liquid qb at the second stage of absorption is greater than the amount of absorbed liquid qa in the first stage and less than 2.5 μl, and the amount of liquid (qb-qa) absorbed in the second stage of absorption is not less than 0.3 μl and not more than 1.4 μl.

(29) The method for determining ink absorption parameters of a recording medium for aqueous ink according to claim 28, wherein the second absorption rate V2 (μl/sec) is greater than 0.05 (μl/sec) and less than 0.23 (μl/sec).

(30) The method for determining ink absorption parameters of a recording medium for aqueous ink according to claim 28, wherein the weight of the base paper and the ink receiving layer is in the range of not less than 180 g/m 2 to not more than 300 g/m 2 , and the second uptake rate V2 (μl/sec) is greater than 0.12 (μl/sec) and less than 0.23 (μl/sec).

With regard to the recording medium for water-based ink according to the present invention, it is preferable that the conditions described above be fully satisfied. However, if even in one of the points there is a slight deviation from these conditions as a result of some unexpected circumstances, such as the presence of dust, such a case is included in the scope of the present invention to the extent that the effect achieved by the implementation of the present invention as a whole is significant. Furthermore, in the case of cut paper or long paper, such as mechanically glazed paper, it is preferred that such paper fall within the scope of the present invention throughout, provided that uniform paper not entirely within the scope of the present invention is considered to be included. to the present invention if the present invention applies substantially to the body of that paper.

Significance of the invention

In accordance with the present invention, the filtration properties that create suitable conditions for the penetration of liquid through the boundary region between the ink-receiving layer and the paper base, which properties have not been achievable until now, are achieved mainly due to the presence of the second stage of absorption. In particular, the most important feature of the present invention lies in the presence of a second absorption stage, in which a process such as association or aggregation of portions of the colorant is carried out, while a given amount (the dominant indicator in terms of optical density of the image; in accordance with the present invention , from 1.3 to 2 µl, preferably 1.5 µl or more, in the above description 4 µl of distilled water) of the liquid passed into the inside of the ink-receiving layer is gradually moved so that conditions (for example, in terms of V2 uptake rate per second absorption stage) defined in each of the above aspects of the present invention. The effect of having the second absorption stage is to improve the optical density of the image and to suppress the loss of sharpness in the image. It is assumed that at the inflection point at the end of this stage, a process is carried out leading to optimal fixation of the colorant within the ink-receiving layer. At this inflection point, the third stage of absorption begins, in which the ink drop is rapidly absorbed by the paper base, accompanied by the diffusion of solvent and moisture, which are no longer needed. It is believed that in this case, to a large extent, there is a separation of the solid and liquid phases. Thus, it is clear that the advantages of the present invention are related to the new filtering function of the boundary region between the ink receptive layer and the paper substrate, which is different from the properties of the conventional interface, which is simply a surface belonging to two layers - the paper substrate and the ink receptive layer.

In any case, according to the present invention, since there is a second absorption stage, due to the presence of which there is a moderate absorption of water-based ink, no matter which water-based ink is dye or pigment, when printing on a recording medium for water-based ink, the weight range of which is can be quite wide - from 130 to 300 g/m 2 , it is possible to minimize image loss of sharpness and obtain a clear image with high density and excellent uniformity. In addition, using the present invention, it is possible to obtain an image that creates a sense of depth when printing on a matte recording medium. Other consequences of the present invention will become clear from the following description.

Description of Preferred Embodiments

<Первое изобретение>

In the first invention described in (1) above, the absorption rates in the first to third absorption steps are determined as follows. A drop of distilled water (23°C) with a volume of 4 µl (microliter) is dropped from a height of about 1 cm onto the surface of the ink-receiving layer of a print carrier for water-based inks after it has been exposed to an atmosphere of 23°C for 24 hours and 50% relative humidity using a microsyringe and a dynamic absorption meter (manufactured by Fibro Co.), operating in an atmosphere of 23° C. and 50% relative humidity; after that, using a video camera, the contour of the fallen drop is photographed, the volume of the drop is determined by analyzing the resulting image, the amount of absorbed liquid and the absorption time are determined by the change in volume over time. Volume is calculated according to the following equation:

V (volume) \u003d π N (0.75 V 2 + N 2) / 6,

where H is the height and B is the diameter of the drop.

Immediately after the fall of the drop, its volume changes rapidly, therefore, it is preferable to reduce the measurement interval to, for example, 0.02 sec.

Printers manufactured by different companies, and even printers from the same manufacturer, use different inks, so distilled water (23°C) was used as a standard in the analysis in the context of the present invention. With an incident drop volume of several pl (picolitres), often used in today's printers, due to the instantaneous absorption of the ink, satisfactory measurements cannot be made. In addition, photographic or the like images are printed on matte water-based ink media with multiple ink colors (eg, six colors) and at a higher speed than glossy media, and the amount of ink used tends to increase. The present invention is based on the discovery that analysis of the absorbance at the surface of the ink-receiving layer, inside the ink-receiving layer, in the boundary region between the ink-receiving layer and the paper base, and further inside the paper base, is consistent with the change in the absorption rate of a 4 μl droplet.

As regards the uptake rates V1, V2, and V3, the amount of liquid uptake at each time point is plotted on a graph as shown in FIG. 2, for example. Then the gradient is equal to the absorption rate. The uptake rate can vary over any length, however, in the context of the present invention, significant uptake rate measurements are referred to as V1, V2, and V3, respectively. That is, at V1, V2 and V3, the absorption rate may slightly increase or decrease. In the context of the present invention, the separation function of the colorant and ink solvent during the printing process is judged by a significant change in the absorption rate.

Reference will be made to Figures 2 and 3 in the course of further explanation.

With the goal of determining the absorption parameters of media that make them suitable for printing with both pigment and dye inks, the inventors of the present invention have found that the print media designated A to I and N to W have the best absorption parameters. In particular, printing media are preferred, the ink absorption parameters of which satisfy the relations 0

In the first absorption stage, the ink droplet is absorbed at the first absorption rate (V1) within one second after falling, mainly on the surface of the ink-receiving layer, this absorption rate is the largest of all three stages. By increasing this speed, it is possible to separate the colorant and the solvent from each other on the surface of the ink receiving layer or within this layer. Particularly in the case of pigmented inks, by separating the colorant from the solvent at an early stage, the aggregation of the colorant is accelerated and high image density can be obtained. In the case of the dye ink, the solvent is quickly separated from the dye, thus it is possible to prevent the image from losing sharpness, which is preferable. If the absorption rate in this step is lower than in the other steps, ink spreads over the surface of the ink-receiving layer.

If the amount of ink absorbed in the first absorption stage is too large, the amount of ink effecting the second and third absorption stages becomes insufficient, and if the amount of ink absorbed is too small, the amount of ink effecting the second and third absorption stages becomes excessive. Therefore, it is optimal that the amount of absorbed liquid qa in the first stage of absorption is greater than 1.3 μl and less than 2.0 μl. With too little absorbed liquid qa, the monolithic homogeneity of the image decreases, while with too much absorbed liquid qa, the optical density of the image decreases.

In the second uptake stage following the first, uptake occurs at a second uptake rate (V2). The ink uptake in the second stage corresponds to the uptake that occurs until a portion of the liquid absorbed into the ink receptive layer begins to permeate through the surface of the paper base into the paper base. It is optimal if this stage takes 2 seconds or more. If this time period is less than 2 seconds, since there is no ink bleeding inside or on the surface of the ink receiving layer, a half dot with insufficient dot gain is generated, in addition, density unevenness occurs, and uniformity of a monolithic image deteriorates. In order to obtain a dot with satisfactory dot gain, it is preferable that the amount of ink absorbed (qb-qa) in the second stage is not less than 0.3 μl and not more than the amount of ink absorbed in the first stage. If the amount of ink absorbed in the second stage is less than 0.3 µl, the dot gain is not enough, while if this amount exceeds the amount absorbed in the first stage, the ink absorption by the paper base becomes large compared to the spreading of the drop, that is, the conditions for the occurrence uneven density.

In particular, a good effect is obtained if the amount of ink (qb-qa) absorbed at the second absorption rate V2 is not less than 0.5 μl. In the third stage of absorption, absorption takes place in the inner region of the paper base.

The first invention defines the absorption parameters of the print media for water-based ink and does not contain restrictions on how exactly this print media is obtained.

Print media for water-based ink, the parameters of which are reflected in figure 2, were obtained using a coating solution, with which the same ink-receiving layer was formed on different base materials; the print media obtained using a paper base with a Steckigt sizing ratio of 15 seconds is designated as A, the print media obtained using a paper substrate with a Steckigt sizing ratio of 50 seconds is designated as B. Comparison of these two samples shows that sample A (paper base with a sizing ratio of 15 seconds) has a shorter second absorption stage. When compared with sample C, in which a different coating solution is used to form an ink receptive layer on the same paper base, and in which silica contains little fine component, although the average particle diameter of amorphous silica is almost the same, it can be seen that for sample A , which uses silicon oxide containing a finely dispersed component, the second stage of absorption is shorter.

It is known that in general the absorption rate of the ink receiving layer is high and that of the paper substrate is low. It is also known that the lower the Steckigt sizing value, the higher the absorption rate. It is likely that the absorption parameters that are the subject of the first invention reflect the phenomenon resulting from the use of amorphous silicon oxide, which is recognized in the works corresponding to this field. In the context of the present invention, it is believed that since the formation of an ink-receiving layer on a paper substrate near the surface of the paper substrate, voids are formed between the elements of cellulose or cellulose and filler, into which the adhesive penetrates and entrains amorphous silicon oxide into these voids, the function of controlling absorption parameters is carried out by the boundary region between the paper base and the ink receiving layer. Due to the penetration of the adhesive, it becomes possible to increase the absorption time in the second stage, and the void-filling amorphous silica starts absorption of the ink within the paper base, which is considered to be the transition to the third stage of absorption.

It is believed that the reason why Sample C, in which silicon oxide contains little fine particle component, has a longer absorption time in the second stage than Sample A, obtained using silicon oxide containing a fine particle component, is the lack of absorption in the inner region of the paper base.

The absorption rate in the first absorption stage does not preclude the use of amorphous silicon oxide, which is in accordance with the prior art, however, can be adjusted by adjusting the content of amorphous silicon oxide.

The absorption rate in the second absorption stage can be controlled by changing the content of the binder in the boundary region between the ink receptive layer and the paper base. Namely, a relatively large content of this component (binder) in the ink-receiving layer is required, which can be achieved by increasing the proportion of the binder in the ink-receiving layer. This adjustment can also be made by changing the drying conditions.

In addition, by reducing the degree of Steckigt sizing of the paper base, it is possible to control the uptake rate in the third uptake stage.

It is preferable that the Steckigt sizing degree of the paper base is not less than 5 seconds and not more than 50 seconds.

In addition, since the color rendering mechanism on a certain print medium is different when using a dye or pigment ink as a coloring agent, it is preferable that the pH value of B, that is, the pH of the ink receiving layer, is:

5<рН В ≤7

Then, excellent color reproduction can be obtained using both dye ink and pigment ink.

In particular, there is a tendency that good color rendering is obtained when the pH A, which is the pH of the paper base, and the pH B of the ink receptive layer satisfy the following relationship:

1<(рН В -рН А)<4

This condition can be met, for example, by adjusting the conditions for obtaining a paper base or by changing the composition of the coating solution used to form the ink-receptive layer.

The thickness of the ink-receiving layer is not particularly limited, but it is particularly preferred that it be not less than 25 µm and not more than 35 µm. For example, when the thickness of the ink-receiving layer is 25 µm or more, it is possible to ensure that a proper amount of ink is absorbed when printed on a printer displaying color balance with six or more colors. However, if the thickness of the ink-receiving layer exceeds 35 μm, the printing density using the dye ink decreases and the film strength deteriorates when viewed from another point of view.

Matte print media for water-based ink is characterized by low gloss, for most media on the market this parameter does not exceed 15% (gloss at an angle of 75°). However, this value is not a limitation in the context of the present invention.

<Различные материалы>

The water-based ink carrier described above can be obtained by combining the selected paper base, the selected components of the ink-receiving layer, and the selected method of forming the ink-receiving layer.

paper base

As examples of the pulp used as the main component of the paper base, chemical pulp, such as LBK and NBKP grades, mechanical pulp, such as GP and TMP grades, and pulp recycled from waste paper, are given. Mixtures of two or more of these pulp types may be used. First of all, it is preferable to use LBKP as the main cellulose component. It is also preferred to use chlorine-free pulp, such as ECF and TCF grades. The grinding degree is not particularly limited, but it is preferable that the grinding be carried out so that the grinding degree is not less than 300 ml and not more than 500 ml (Industry standard: JIS-P-8121). As the freeness increases, the waviness of the paper when printing tends to increase, color unevenness is also easily generated, while when the freeness is low, there is a possibility that the surface will not be smooth.

The paper base may contain not only cellulose, but also a filler. The filler is used to control the air permeability of the paper substrate, thereby imparting opacity to the paper substrate, or to control the ability to absorb ink. Examples of suitable fillers include clay, kaolin, calcined kaolin, talc, calcium carbonate, magnesium carbonate, aluminum hydroxide, calcium hydroxide, silica and titanium oxide. First of all, calcium carbonate is preferred because it produces a paper base with a high degree of whiteness.

Preferably, the filler content is at least 1 wt. parts and not more than 35 wt. parts per 100 wt. parts of pure cellulose. If the filler content is low, there is a possibility that not only will the whiteness of the paper decrease, but the ink absorption capacity will also deteriorate. If the filler content is too high, the stiffness and ink capacity of the paper decreases.

The degree of Steckigt sizing of the paper base used in the print medium for the aqueous ink according to the present invention is controlled, for example, by any of the sizing agents for internal use, such as rosin, alkenyl succinic anhydride, alkyl ketene dimer, and coumarone-indene resins. as well as adhesives for surface use such as rosin glue, coumarone-indene resins, starches such as oxidized starch, acetylated starch and hydroxyethyl starch, their derivatives, polyvinyl alcohols and their derivatives, synthetic resins containing copolymers of two or more monomers from the group consisting of styrene, alkyd, polyamide, acrylic, olefin, maleic acid and vinyl acetate, emulsions and waxes based on these synthetic resins.

The Steckigt sizing degree of the paper base is determined according to JIS P 8122, and is preferably 5 to 50 seconds. If the Steckigt sizing degree is less than 5 seconds, any component of the coating material of the ink receptive layer may penetrate into the paper base, or the binder contained in the coating material penetrates into the base material, therefore, the surface strength of the film is reduced. This is probably the reason why it is not possible to improve color rendering with either dye ink or pigment ink even if the ink receptive layer according to the present invention is provided. If the Steckigt sizing rate exceeds 50 seconds, the water resistance of the printed area is reduced.

The paper manufacturing method is not particularly limited. The paper can be made on known papermaking equipment such as, for example, a Fourdrinier machine, a cylinder or a twin wire machine. Both acidic paper and neutral paper are applicable, depending on the pH of the raw material used to make the paper. It is preferred that this material has a specific pH A, and it is also preferred to use acidic paper.

When using a size press or the like, for example, starch, polyvinyl alcohol or cationic resin can be used to be absorbed by the surface of the paper, whereby it is possible to control the smoothness of the surface of the paper, improve its printability and writing. In addition, the base paper may be flattened with a calender or the like to improve its smoothness. pH A can be controlled by the use of an appropriate pH adjusting agent. Preferably, the weight of the paper base is not less than 130 g/m 2 and not more than 300 g/m 2 .

Ink receiving layer

The ink receptive layer contains at least one inorganic pigment, one adhesive, and a substance that reacts with the coloring matter of the ink, such as a cationic ink fixative.

Examples of useful inorganic pigments include clay, kaolin, calcined kaolin, talc, calcium carbonate, magnesium carbonate, aluminum hydroxide, calcium hydroxide, amorphous silica, and titanium oxide.

First of all, the preferred inorganic pigment is amorphous silica because, compared to other pigments, it provides the best color rendering and ink absorption capacity. The method for producing amorphous silicon oxide is not particularly limited. We can use amorphous silicon oxide produced by any method: electric arc, dry or wet (precipitation, gelation). However, wet silica is preferred because it is suitable for both the pigment water-based ink recording medium and the dye water-based ink recording medium.

The average diameter of the secondary particles of amorphous silica is not particularly limited as long as the ink receiving layer of the aqueous ink recording medium satisfies the absorption parameters of the present invention, but is preferably not more than 10 µm, more preferably not less than 4 µm, and no more than 8 microns. If the average secondary particle diameter of the amorphous silica is larger than 10 µm, there is a possibility of deterioration in image clarity, noticeable surface roughness, printing unevenness in both the dye water-based ink recording medium and the pigment water-based ink recording medium. If the average secondary particle diameter of the amorphous silica is less than 4 µm, and if such amorphous silica is used in the recording medium for the aqueous dye ink, the absorbency of the dye ink tends to deteriorate. If the particle size of the amorphous silica is even smaller, the ink transmittance of the ink receiving layer is increased, therefore, the light fastness of the dye ink print tends to deteriorate, or the strength of the film decreases. In addition, in the case of using such amorphous silica particles in a recording medium for water-based pigmented particles, there is a possibility that the fixing quality of the pigmented ink is degraded.

In accordance with this document, the average particle diameter of silicon oxide, determined using a particle counter according to the Coulter principle, is the volume averaged particle diameter obtained from a sample of silicon oxide subjected to dispersion in distilled water by ultrasound for 30 seconds.

It is particularly preferred that the amorphous silica having such an average secondary particle diameter has a wide (in the range of 1 to 9 µm as a guideline) particle size distribution and contains fine particles capable of penetrating between the cellulose fibers on the surface of the paper base. Generally, the binder contained in the ink receptive layer and the cationic resin component penetrate and partially coat the surface of the paper substrate in the boundary region thus formed between the ink receptive layer and the paper substrate of a water-based ink recording medium. Moreover, the rate of absorption by the actual paper base, in comparison with the rate of absorption by the ink-receiving layer, is very high. And in such a paper base, the absorption rate is greatly reduced, and the ink solvent cannot be absorbed uniformly into the paper base. That is, absorption rates according to the present invention are not observed in many cases. The silica fine particles enter the gaps formed between the cellulose fibers on the surface of the base paper in the boundary region thus formed between the ink-receiving layer and the base paper of the water-based ink carrier. This is expected to increase the absorption rate of the paper substrate and create conditions for the absorption of the ink solvent to enhance the performance of the paper substrate. This action effectively suppresses excessive spreading of the dropped ink drop. When the rate of absorption of ink by the paper base is reduced, there is a tendency for the ink drop in question to overspread, a decrease in print density and loss of sharpness in the image become likely.

The use of an adhesive in the ink-receiving layer is not particularly limited. Known, commonly used in printing media hydrophilic adhesives are applicable. Examples thereof include proteins such as casein, soy protein and artificial protein, starches such as starch and oxidized starch, polyvinyl alcohols and their derivatives, cellulose derivatives such as carboxymethylcellulose and methylcellulose, polydiene resins such as styrene-butadiene copolymer and a copolymer of methyl methacrylate and butadiene, acrylic resins such as polymers or copolymers of acrylic acid, methacrylic acid, esters of acrylic acid and methacrylic acid, vinyl resins such as a copolymer of ethylene and vinyl acetate. These adhesives may be used alone or in combination of two or more components.

First of all, polyvinyl alcohols are the best in terms of adhesion to pigments and are therefore preferred. Polyvinyl alcohol derivatives such as silanol-modified polyvinyl alcohol and cationized polyvinyl alcohol can also be used.

The ratio of the amounts of silicon oxide and adhesive is such that the adhesive is used in an amount of at least 30 wt. parts and not more than 70 wt. parts, preferably at least 40 wt. parts and not more than 60 wt. parts per 100 wt. parts of silicon oxide. If a large amount of adhesive is used, the penetration rate decreases, while if it is small, the amount of adhesive in the boundary region between the base paper and the ink-receiving layer decreases, and it becomes impossible to control absorption parameters. If the amount is extremely small, the strength of the ink receiving layer tends to decrease.

On the other hand, the use of substances reactive with the coloring matter of the ink in the composition of the ink receiving layer is not particularly limited. Particularly preferred is a cationic ink fixative. Commercial examples of cationic ink fixatives include: (1) polyalkylene polyamines such as polyethylene polyamine and polypropylene polyamine and their derivatives; (2) polyacrylates containing a secondary amino group, a tertiary amino group or a quaternary ammonium group; (3) polyvinylamine, polyvinylamidine and five-membered cyclic amidines; (4) cationic cyanogen resins typified by a copolymer of dicyanamide and formalin; (5) polyamine-based cationic resins typified by a copolymer of dicyanamide and polyethyleneamine; (6) a copolymer of dimethylamine and epichlorohydrin; (7) a copolymer of diallyldimethylammonium and SO 2 ; (8) copolymer of diallylamine salt and SO 2 ; (9) dimethyldiallylammonium polychloride; (10) polymeric salt of allylamine; (11) a vinylbenzyltriallylammonium salt homopolymer or copolymer; (12) dialkylaminoethyl(meth)acrylate quaternary salt copolymers; (13) acrylamide-diallylamine copolymer; (14) aluminum salts such as aluminum polychloride and aluminum polyacetate. These cationic ink fixatives may be used alone or in combination of two or more components.

It is preferred that acrylamide-diallylamide copolymer be used in combination with diallyldimethylammonium chloride. The reason is that this combination gives excellent color reproduction when printed with pigment ink, and excellent color reproduction and shelf life when printed with dye ink. It is believed that this improvement in color reproduction is due to the fact that in both cases the colorant is fixed in the ink-receiving layer without agglomeration.

The content of the cationic ink fixative is preferably not less than 5 wt. parts and not more than 60 wt. parts per 100 wt. parts of the pigment used. More preferably, this value lies in the range from 20 to 50 wt. parts. If the content of the fixative ink is less than 5 wt. parts, image clarity may deteriorate, and if this value is greater than 60 wt. parts, appearance may deteriorate after coating.

If necessary, various additives used in the production of conventional coated paper, such as thickener, defoamer, wetting agent, surfactant, coloring agent, antistatic agent, lightfastener, ultraviolet absorber, antioxidant and antiseptic. By porous layer is meant a layer in which there are pores on the surface of the inorganic pigment particles, or there are gaps or voids between the particles, even if this layer contains a water-soluble adhesive.

The amount of the coating material of the ink receptive layer is not particularly limited, but is preferably not less than 10 g/m 2 and not more than 20 g/m 2 . If the amount of coating material is less than the specified lower limit, image clarity is likely to deteriorate, while if the amount is greater than the specified upper limit, film strength and image clarity may decrease when viewed from a different point of view. The ink-receiving layer may be a layered structure consisting of several layers, in which case the composition of the individual layers of the ink-receiving layer may be different.

The ink receiving layer can be formed by any type of coater, such as doctor blade coater, air knife coater, roller coater, bar coater, serrated roller coater, roller scraper, apron device, curtain coater, sizing press.

The drying conditions of the ink receptive layer are controlled, for example, by changing the concentration of the coating solution of the ink receptive layer. The nature of the change in the absorption rate also depends on the drying conditions. It is preferable to use as harsh a drying condition as possible, however, excessive drying may cause color deterioration. After the coating has been applied, finishing can be carried out using a calender, such as a multi-roll calender, a super calender or a soft calender. However, since such processing leads to the destruction of the voids present on the surface of the ink-receiving layer, it is preferable to adjust this process so that the absorption rate does not go beyond the predetermined range.

Inventions 2 to 4

The absorption rate determination method according to the second invention described in (12) above is the same as that of the first invention. According to the second invention, it is preferred that V1, V2 and V3 satisfy the relation 0

The amount of liquid absorbed in the first stage of absorption qa is set to a value of not less than 1.5 µl and not more than 2.0 µl, the amount of liquid absorbed in the second stage of absorption (qb-qa) is set to a value of not less than 0.3 µl and not more than 1.0 µl. These absorbing parameters enable solid-liquid separation to be promoted and sufficient ink flow to be ensured.

In accordance with the second invention, it is important that the absorption of ink in the second stage was moderate. This means carrying out ink absorption in the part where the coloring matter of the ink is to be fixed.

The absorption rate determination method according to the third invention described in (15) above is the same as that of the first invention. According to the third invention, it is preferred that V1, V2 and V3 satisfy the relation 0

If such absorption parameters are achieved, it becomes possible to promote the separation of the solid and liquid phases and ensure sufficient spreading of the ink.

It is also important according to the third invention that the absorption of ink in the second stage be moderate. This means carrying out ink absorption in the part where the coloring matter of the ink is to be fixed. In quantitative terms, it is preferable that the amount of liquid (qb-qa) during this period is in the range of 0.3 to 1.0 µl, more preferably 0.5 to 1.4 µl. In practical implementation, the preferred range is from 0.3 (or 0.5) to 1.0 μl.

The absorption rate determination method according to the fourth invention described in (18) above is the same as that of the first invention. According to the fourth invention, the amount of liquid absorbed in the first stage of absorption qa is set to a value of not less than 1.3 μl and less than 2.0 μl, and the amount of liquid absorbed qb in the second stage of absorption is set to a value greater than the amount of liquid qa absorbed in the first stage and less than 2.5 µl. In addition, the liquid amount (qb-qa) absorbed in the second absorption step is set to not less than 0.3 µl and not more than 1.4 µl. If such absorption parameters are achieved, it becomes possible to promote the separation of the solid and liquid phases and ensure sufficient spreading of the ink.

According to the fourth invention, it is also important that the absorption of ink in the second stage is moderate. This means carrying out ink absorption in the part where the coloring matter of the ink is to be fixed. In quantitative terms, it is preferable that the amount of liquid (qb-qa) during this period is in the range of 0.3 to 1.4 µl, more preferably 0.5 to 1.4 µl. In practical implementation, the preferred range is from 0.3 (or 0.5) to 1.0 μl.

In the second to fourth inventions, attention is paid to changing the absorption parameters of the ink, and no particular limitation is set, except that the water-based ink contains an anionic colorant, and that the recording medium for water-based ink has a porous layer containing an inorganic pigment and a substance entering into reaction with the colorant of the ink. Suitable known bases, inorganic pigments, cationic compounds and binders are suitable for this. The porous layer mainly plays the role of the ink receiving layer.

It is preferable that the pH of the porous layer is greater than 5 and not greater than 7, and that the porous layer includes an underlying cellulose layer that performs the function of absorbing ink, while the pH of the cellulose layer does not exceed the pH of the porous layer. In addition, it is preferable that the Steckigt sizing degree of the paper base is not less than 5 seconds and not more than 50 seconds.

EXAMPLES

Hereinafter, the present invention will be described in more detail with reference to illustrative examples, and it goes without saying that the present invention is not limited thereto. In the following examples, fractional and percentage values ​​refer to solid materials, with the exception of water, and, unless otherwise indicated, are parts by weight and weight percent, respectively.

The Steckigt sizing ratio of the base paper and the print density and water resistance of the print medium for water-based ink obtained in the following Examples and Comparative Examples were found as follows.

To quantify these parameters, the recording medium for aqueous ink was printed with a commercially available inkjet printer (trade name: Image PROGRAF W6200, manufactured by Canon Inc., print mode: thick coated paper/high quality) with pigment ink and a commercially available inkjet printer. printer (brand name: PIXUS ip8600, manufactured by Canon Inc., print mode: matte photo paper/high quality).

The degree of sizing according to Steckigt

The Steckigt sizing degree of each base paper sample was determined in accordance with JIS P 8122.

Print Density

An image ("XYZ/JIS-SCID high-definition color digital standard image", identification symbol: S6, image name: gamut scale) published by the Japan Standards Association was applied to the media using two types of printers - Image PROGRAF W6200 (with ink pigment) and PIXUS ip8600 (dye ink); the print density was determined by the parts with the most intense color tone of black and magenta using RD-914 (manufactured by Guretag Macbeth Co.).

Loss of sharpness

For images obtained with the Image PROGRAF W6200 and PIXUS ip8600 types, the loss of sharpness at the border of the black and red parts was determined visually.

Criteria:

No loss of sharpness, excellent quality

◯: slight loss of sharpness, but without problems in practical use

∆ : slight loss of sharpness causing some problems in practical use

× : noticeable loss of sharpness causing serious problems in practical use

Image Uniformity

The black portions of the image produced by the spirit-type printers - Image PROGRAF W6200 and PIXUS ip8600 - were evaluated visually according to the following criteria:

Excellent monolithic uniformity, the image creates a sense of depth, high quality

◯: good monolithic uniformity, good quality

∆ : slightly lacking uniformity

× : bad

EXAMPLE 1

Paper base I

10 parts of calcined kaolin was added to 100 parts of bleached hardwood kraft paper (grinding ratio 400 ml, industry standard: JIS-P-8121), then 1.0 parts of cationic starch, 0.7 parts of rosin glue, and 2. 0 parts of crude aluminum sulphate, everything was thoroughly mixed, obtaining the starting material for making paper. Then, paper was made on a Fourdrinier multi-cylinder paper machine and dried to a moisture content of 10%. Thereafter, 4 g/m 2 of a 7% aqueous solution of oxidized starch was applied to both surfaces of the paper using a size press, dried to a moisture content of 5.0%, and as a result, base paper I having a weight of 190 g/m was obtained. 2 and Steckigt gluing degree 15 sec.

Preparation of the Coating Solution for the Ink Receptive Layer

100 parts of silicon oxide obtained by wet processing of silicon oxide (trade name: NIPGEL AY603, manufactured by TOSOH SILICA Co.) with a weight average secondary particle diameter of 6.6 μm, in which 47% of the total amount of silica by the number of particles has a weight average diameter secondary particles no more than 2 microns, which is achieved using a sand mill, as a pigment; 35 parts of silyl-modified polyvinyl alcohol (trade name: R-1130, manufactured by KURARAY Co.) as an adhesive; 5 parts polyvinyl alcohol (trade name: PVA 135, manufactured by KURARAY Co.); 10 parts styrene-acrylic copolymer; 20 parts of acrylamide-diallylamine copolymer (trade name: SR1001, manufactured by Sumitomo Chemical Co.) as an ink fixative; 10 parts of diallyldimethylammonium chloride (trade name: CP101, manufactured by SENKA Co.) and water were mixed and dispersed to obtain a coating solution.

The coating solution of the ink receptive layer was applied to one of the surfaces of the base paper I so that the coating amount was 12 g/m 2 , then dried with the time to start drying set to 5 seconds, and a recording medium for water-based ink was obtained. The weight of this print medium was 202 g/m 2 .

The recording medium for water-based ink thus obtained was subjected to the above-described measurement and evaluation procedures, the results of which are shown in Table 2. The ratio of absorption rate, absorption time, and amount of absorbed liquid at each stage for this recording medium is as shown in Table 1 and in FIG. Option 2 marked A.

EXAMPLE 2

A recording medium for water-based ink was made in the same manner as in Example 1, except for changing the sizing composition of the base paper I obtained in Example 1 to the following: oxidized starch: PVA: styrene-acrylic copolymer = 4:0.5:0.5 (5% solution) and changes in the degree of sizing according to Steckigt equal to 50 sec.

The recording medium for water-based ink thus obtained was subjected to the above-described measurement and evaluation procedures, the results of which are shown in Table 2. The ratio of absorption rate, absorption time, and amount of absorbed liquid at each stage for this recording medium is as shown in Table 1 and in FIG. Option 2 marked B.

EXAMPLE 3

A recording medium for water-based ink was made in the same manner as in Example 1, except that the pigment contained in the coating solution of the ink-receiving layer was changed to silicon oxide obtained by processing silicon oxide by a wet fine grinding method with a weight average secondary particle diameter of 7 .0 μm, in which 20% of the total amount of silicon oxide by the number of particles have a weighted average diameter of secondary particles of not more than 2 μm, which is achieved using a sand mill and subsequent sorting.

The recording medium for water-based ink thus obtained was subjected to the above-described measurement and evaluation procedures, the results of which are shown in Table 2. The ratio of absorption rate, absorption time, and amount of absorbed liquid at each stage for this recording medium is as shown in Table 1 and in FIG. Option 2 marked C.

EXAMPLE 4

A recording medium for aqueous ink was made in the same manner as in Example 1, except that the weight of the base paper I was changed to 220 g/m 2 . The print media weight was 232 g/m 2 . The results obtained are presented in table 1.

The recording medium for water-based ink thus obtained was subjected to the above-described measurement and evaluation procedures, the results of which are shown in Table 2. The ratio of absorption rate, absorption time, and amount of absorbed liquid at each stage for this recording medium is as shown in Table 1 and in FIG. Option 2 marked with the letter D.

EXAMPLE 5

A recording medium for water-based ink was made in the same manner as in Example 1, except that the time to start drying in the manufacture of a recording medium for water-based ink was changed to 10 seconds.

The recording medium for water-based ink thus obtained was subjected to the above-described measurement and evaluation procedures, the results of which are shown in Table 2. The ratio of absorption rate, absorption time, and amount of absorbed liquid at each stage for this recording medium is as shown in Table 1 and in FIG. Option 2 labeled E.

EXAMPLE 6

A recording medium for water-based ink was made in the same manner as in Example 1, except that the time to start of drying in the manufacture of a recording medium for water-based ink was changed to 15 seconds.

The recording medium for water-based ink thus obtained was subjected to the above-described measurement and evaluation procedures, the results of which are shown in Table 2. The ratio of absorption rate, absorption time, and amount of absorbed liquid at each stage for this recording medium is as shown in Table 1 and in FIG. 2 option, marked with the letter F.

EXAMPLE 7

The recording medium for water-based ink was made in the same manner as in Example 1, except that the time to start drying in the manufacture of the recording medium for water-based ink was changed to 20 seconds.

The recording medium for water-based ink thus obtained was subjected to the above-described measurement and evaluation procedures, the results of which are shown in Table 2. The ratio of absorption rate, absorption time, and amount of absorbed liquid at each stage for this recording medium is as shown in Table 1 and in FIG. 2 option, marked with the letter G.

EXAMPLE 8

A recording medium for water-based ink was made in the same manner as in Example 1, except that the time to start drying in the manufacture of a recording medium for water-based ink was changed to 25 seconds.

The recording medium for water-based ink thus obtained was subjected to the above-described measurement and evaluation procedures, the results of which are shown in Table 2. The ratio of absorption rate, absorption time, and amount of absorbed liquid at each stage for this recording medium is as shown in Table 1 and in FIG. Option 2, marked with the letter N.

EXAMPLE 9

A recording medium for water-based ink was made in the same manner as in Example 1, except that the time to start drying in the manufacture of a recording medium for water-based ink was changed to 30 seconds.

The recording medium for water-based ink thus obtained was subjected to the above-described measurement and evaluation procedures, the results of which are shown in Table 2. The ratio of absorption rate, absorption time, and amount of absorbed liquid at each stage for this recording medium is as shown in Table 1 and in FIG. Option 2, marked with the letter I.

Comparative Example 1

Paper base II

A mixture of 75:25 of light calcium carbonate and kaolin was added to 100 parts of bleached hardwood kraft paper (fineness 400 ml, industry standard: JIS-P-8121), then added 1.0 part of cationic starch, 0. 04 of a neutral alkenyl succinic anhydride size and 2.0 parts of crude aluminum sulphate were all thoroughly mixed to form the starting material for making paper. Then, paper was made on a Fourdrinier multi-cylinder paper machine and dried to a moisture content of 10%. After that, using a size press, 4 g/m 2 of a 7% aqueous solution of a 5.2:1.3:0.6 mixture of oxidized starch, PVA and styrene-acrylic copolymer was applied to both surfaces of the paper, dried to moisture content of 5.0% and, as a result, received a paper base II, having a weight of 190 g/m 2 and the degree of sizing according to Steckigt 300 sec.

Making Printing Media for Water-Based Ink

A recording medium for water-based ink was made in the same manner as in Example 1, except that the base paper I used in Example 1 was changed to base paper II.

The recording medium for water-based ink thus obtained was subjected to the above-described measurement and evaluation procedures, the results of which are shown in Table 2. The ratio of absorption rate, absorption time, and amount of absorbed liquid at each stage for this recording medium is as shown in Table 1 and in FIG. 2 option, marked with the letter J.

Comparative Example 2

The above-described measurement and evaluation procedures were carried out on a commercially available matte printing medium for water-based ink (trade name: Thick Coater Paper, manufactured by Canon Inc.), the results are shown in Table 2. media correspond in table 1 and in figure 2 to the variant indicated by the letter K.

Comparative Example 3

The above-described measurement and evaluation procedures were carried out on a commercially available matte printing medium for water-based ink (trade name: Photo Mat Paper/Pigment type, manufactured by EPSON Co.), the results are shown in Table 2. Relationship between absorption rate, absorption time, and liquid absorption amount at each stage of absorption for a given printing medium correspond in table 1 and in figure 2 to the variant indicated by the letter L.

Comparative Example 4

The measurement and evaluation procedures described above were carried out on a commercially available matte printing medium for water-based ink (trade name: PM Mat Paper, manufactured by EPSON Co.), the results are shown in Table 2. Relationship between absorption rate, absorption time, and liquid absorption amount in each stage absorbances for this printing medium correspond in table 1 and in figure 2 to the variant marked with the letter M.

For the prints obtained in the Examples and Comparative Examples, the continuous print areas were examined and found that in Examples 1 to 9, the images had a uniform gloss, were clear in both the pigment ink and the dye ink, but in the Comparative Examples with 1 to 4 images have uneven gloss and are fuzzy. The ink-receiving layer of the recording media in Examples 1 to 9 and Comparative Examples 1 to 4 was removed with a razor, and in each case, the boundary region between the base paper and the ink-receiving layer was examined for the presence of silicon oxide with a scanning electron microscope, whereby that, in Examples 1 to 9, silica particles were present on both the paper base side and the ink receptive layer side with respect to the boundary region between the ink receptive layer and the paper base.

From the results obtained in Examples and Comparative Examples, it can be seen that the absorption rate in the second stage in each of Examples 1 to 9 is not less than 0.12 µl/s and not more than 0.23 µl/s, exceeds the value of the absorption rate, equal to 0.01 μl/sec in the examples indicated by J and K, and does not exceed the value of the absorption rate equal to 0.32 μl/sec in the example indicated by L. It is also seen that when the amount of absorbed liquid qa in the first stage is not less than 1.6 μl, the absorption time (tb-ta) in the second stage of absorption is not less than 2 seconds, since this amount is relatively large, however, it is absorbed in a relatively short time. In addition, the amount of absorbed liquid (qb-qa) in the second stage of absorption in each of these examples is not less than 0.39 μl and not more than 0.80 μl, which is half or less of the amount of absorbed liquid qa in the first stage of absorption. Let's explain this in terms of ink absorption. A relatively large amount of ink is absorbed in a short time in the first stage of absorption, however, it is believed that the absorbed ink has adequate holding capacity and moves without causing loss of image sharpness, therefore, a balance is achieved, resulting in increased print density and image clarity. This becomes apparent when looking at the resulting images. In particular, the time value tb in the second stage of absorption from the moment the drop falls is in the range from 2.5 to 6.1 s, and the value of time (tb-ta) in the second stage of absorption is not less than 2.3 s and not more than 5 .8 sec.

In the above examples, the total weight of the base paper and the ink receiving layer is not less than 180 g/m 2 and not more than 300 g/m 2 , that is, these illustrative examples are suitable as so-called thick paper. On the other hand, the following additional examples show that the present invention is also effective for conventional thickness print media. Although the following examples use a thin paper base, the technical idea of ​​the present invention does not depend on the thickness or weight; it has been shown that each of the described aspects of the present invention can be effective if the structural conditions specified herein are met. In this regard, the following examples are typical.

Paper Base III

As in the preparation of paper base I, 10 parts of calcined kaolin was added to 100 parts of bleached hardwood kraft paper (fineness 400 ml, industry standard: JIS-P-8121), then 1.0 parts of cationic starch, 0.7 parts of rosin glue and 2.0 parts of crude aluminum sulphate, all thoroughly mixed, getting the starting material for making paper. Then, paper was made on a Fourdrinier multi-cylinder paper machine and dried to a moisture content of 10%. Thereafter, 4 g/m 2 of a 7% aqueous solution of oxidized starch was applied to both surfaces of the paper using a size press, dried to a moisture content of 5.0%, and as a result, a base paper III having a weight of 150 g/m was obtained. 2 and Steckigt gluing degree 10 sec.

EXAMPLE 10

A recording medium for water-based ink was made in the same manner as in Example 1, except that the base paper I used in Example 1 was changed to base paper III. The weight of the recording medium for water-based ink thus obtained was 162 g/m 2 .

For this print medium for aqueous ink, the evaluation procedures described above were carried out, the results of which are presented in Table 4. The absorption rate, absorption time and the amount of liquid absorbed at each stage for this print medium are indicated in Table 3 and in Fig. 3 by the letter N.

EXAMPLE 11

A recording medium for water-based ink was made in the same manner as in Example 1, except that the base paper I used in Example 1 was changed to paper base III, and the time to start drying was changed to 10 seconds.

The recording medium for water-based ink thus obtained was subjected to the above-described evaluation procedures, the results of which are shown in Table 4. The absorption rate, absorption time, and amount of liquid absorbed in each stage for this recording medium are indicated in Table 3 and in FIG. 3 letter O.

EXAMPLE 12

A recording medium for water-based ink was made in the same manner as in Example 1, except that the base paper I used in Example 1 was changed to paper base III, and the time to start drying was changed to 3 seconds.

For the thus obtained recording medium for water-based ink, the evaluation procedures described above were carried out, the results of which are presented in Table 4. The absorption rate, absorption time and the amount of liquid absorbed at each stage for this recording medium are indicated in Table 3 and in Fig. 3 by the letter P .

EXAMPLE 13

A recording medium for water-based ink was made in the same manner as in Example 1, except that the paper base I used in Example 1 was changed to paper base III, the time before drying was changed to 3 seconds, and the drying temperature was changed to 160° WITH.

For the thus obtained recording medium for water-based ink, the evaluation procedures described above were carried out, the results of which are presented in Table 4. The absorption rate, absorption time and the amount of liquid absorbed at each stage for this recording medium are indicated in Table 3 and in Fig. 3 by the letter Q .

EXAMPLE 14

A recording medium for aqueous ink was made in the same manner as in Example 1, except that the base paper I used in Example 1 was changed to paper base III, and the drying temperature was changed to 160°C.

For the thus obtained recording medium for water-based ink, the above evaluation procedures were carried out, the results of which are presented in Table 4. The absorption rate, absorption time and the amount of absorbed liquid at each stage for this recording medium are indicated in Table 3 and in Fig. 3 by the letter R .

EXAMPLE 15

As in the preparation of paper base I, 10 parts of calcined kaolin was added to 100 parts of bleached hardwood kraft paper (fineness 400 ml, industry standard: JIS-P-8121), then 1.0 parts of cationic starch, 0.7 parts of rosin glue and 2.0 parts of crude aluminum sulphate, all thoroughly mixed, getting the starting material for making paper. Then, paper was made on a Fourdrinier multi-cylinder paper machine and dried to a moisture content of 10%. Thereafter, 4 g/m 2 of a 7% oxidized starch aqueous solution was applied to both surfaces of the paper using a size press, dried to a moisture content of 5.0%, and as a result, a base paper IV having a weight of 127 g/m was obtained. 2 and Steckigt gluing degree 9 sec.

A recording medium for aqueous ink was made in the same manner as in Example 1, except that the base paper I used in Example 1 was changed to base paper IV. The weight of this print medium for water-based ink was 139 g/m 2 .

For the thus obtained recording medium for water-based ink, the evaluation procedures described above were carried out, the results of which are presented in Table 4. The absorption rate, absorption time and the amount of absorbed liquid in each stage for this recording medium are indicated in Table 3 and in Fig. 3 by the letter S .

EXAMPLE 16

A recording medium for aqueous ink was made in the same manner as in Example 1, except that the base paper I used in Example 1 was changed to base paper IV, and the time to start drying was changed to 10 seconds.

For the thus obtained recording medium for water-based ink, the evaluation procedures described above were carried out, the results of which are presented in Table 4. The absorption rate, absorption time and the amount of liquid absorbed at each stage for this recording medium are indicated in Table 3 and in Fig. 3 by the letter T .

EXAMPLE 17

A recording medium for aqueous ink was made in the same manner as in Example 1, except that the base paper I used in Example 1 was changed to base paper IV, and the time to start drying was changed to 3 seconds.

For the thus obtained recording medium for water-based ink, the above evaluation procedures were carried out, the results of which are presented in Table 4. The absorption rate, absorption time and the amount of absorbed liquid in each stage for this recording medium are indicated in Table 3 and in Fig. 3 by the letter U .

EXAMPLE 18

A recording medium for water-based ink was made in the same manner as in Example 1, except that the paper base I used in Example 1 was changed to paper base IV, the time to start drying was changed to 3 seconds, and the drying temperature was changed to 160° WITH.

The recording medium for water-based ink thus obtained was subjected to the above-described evaluation procedures, the results of which are shown in Table 4. The absorption rate, absorption time, and amount of liquid absorbed in each stage for this recording medium are indicated in Table 3 and in FIG. 3 letter V.

EXAMPLE 19

A recording medium for water-based ink was made in the same manner as in Example 1, except that the base paper I used in Example 1 was changed to base paper IV, and the drying temperature was changed to 160°C.

For the thus obtained recording medium for water-based ink, the evaluation procedures described above were carried out, the results of which are presented in Table 4. The absorption rate, absorption time and the amount of absorbed liquid in each stage for this recording medium are indicated in Table 3 and in Fig. 3 by the letter W .

From the above examples, it can be seen that in the case where qa (not less than 1.3 μl) in the first stage of absorption, in accordance with the present invention, is less than 1.60 μl, the amount of liquid absorbed in the first stage is relatively small, therefore, the colorant fixation corresponding to a certain image density can be affected by adjusting the liquid absorption amount (qb-qa) in the second absorption stage so that the absorption is relatively long and smooth. In particular, it is preferable that the time tb, which is the beginning of the third absorption stage, be at least 9.5 sec, and that the absorption rate V2 in the second absorption stage be at least 0.01 μl/sec and less than 0.12 μl/sec . In print media N, O, P, Q, R, S, T, U, V and W, the time tb in the second stage of absorption is not less than 9.6 s and not more than 13.5 s, and the absorption rate V2 is not less than 0.05 µl/s and not more than 0.09 µl/s. For the present invention, this condition is more efficient. In particular, this range indicates that the present invention is suitable in the case of a recording medium weighing at least 130 g/m 2 and less than 180 g/m 2 , that is, having a normal thickness.

It can be seen from Tables 1-4 above that in the examples illustrating the present invention, the uptake rate V2 in the second uptake stage is higher than the uptake rate of 0.01 μl/sec for samples J and K, and lower than the uptake rate 0.32 µl/sec for sample L. In particular, the uptake rates for A, B, C, D, E, F, G, H, and I are 12 to 17 times faster than the uptake rates for J and K, and are about half the absorption rate for L. For samples N, O, P, Q, R, S, T, U, V, and W, the absorption rates in the second stage of absorption are 5 to 8 times higher than the uptake rate for J and K, and are about one-sixth to one-fourth the uptake rate for L. That is, the "moderate" rate described herein is not less than 0.05 µl/s and not more than 0 .23 µl/sec. For the present invention, this condition is more efficient.

As described above, the present invention is effective regardless of the thickness and weight of the recording medium, if a drop of distilled water with a volume of 4 μl falling on the surface of the ink-receiving layer is absorbed in the first stage of absorption at the first absorption rate V1 (μl/sec) for one second after the fall, in the second uptake stage at a second uptake rate V2 (µl/sec) for at least 2 seconds after the first uptake stage, and in the third uptake stage following the second uptake stage at a third uptake rate V3 (µl/sec) sec), while the absorption of a drop at all, from the first to the third, stages of absorption satisfies the following relation:

provided that the inflection point between the first and second absorption stages is a, the inflection point between the second and third absorption stages is b, the end point of the third absorption stage is c, the amounts of liquid absorbed at points a, b and c are qa, qb and qc , respectively, the time to reach points a, b and c is ta, tb and tc, respectively, the amount of absorbed liquid qa at the inflection point a is not less than 1.3 μl and less than 2.0 μl, the amount of absorbed liquid qb at point b is greater the amount of qa absorbed in the first stage and less than 2.5 μl, the amount (qb-qa) absorbed in the second stage of absorption is not less than 0.3 μl and not more than 1.4 μl.

In addition, it has been found that if the second absorption stage takes place 9.5 seconds after the fall of the drop, and the time tc to the end point of the third stage of absorption is up to 14.5 seconds after the fall of the drop, the present invention is satisfactorily effective, even in the case of media with a thin paper base.

Brief description of the drawings

1 is an explanatory graph showing the parameters of conventional print media determined by the method of the present invention;

Fig. 2 is an explanatory graph showing absorption parameters of print media according to one embodiment of the present invention;

Fig. 3 is an explanatory graph showing absorption parameters of print media according to another embodiment of the present invention.

In these drawings, A denotes the absorption rate for the aqueous ink recording medium made in Example 1, B denotes the absorption rate for the aqueous ink recording medium made in Example 2, C denotes the absorption rate for the aqueous ink recording medium made in Example 3, the letter D is the absorption rate for the aqueous ink recording medium made in Example 4, the letter E is the absorption rate for the aqueous ink recording medium made in Example 5, the letter F is the absorption rate for the aqueous ink recording medium, made in example 6, letter G is the absorption rate for the recording medium for water-based ink made in example 7, letter H is the absorption rate for the recording medium for water-based ink made in example 8, letter I is the absorption rate for the recording medium for water-based ink , manufactured in approx. 9, J is the absorption rate of the aqueous ink recording medium made in Comparative Example 1, K is the absorption rate of the aqueous ink recording medium manufactured in Comparative Example 2, L is the absorption rate of the aqueous ink recording medium , made in Comparative Example 3, M is the absorption rate of the water-based ink recording medium made in Comparative Example 4, N is the absorption rate of the water-based ink recording medium made in Example 10, O is the absorption rate of the recording medium for water-based ink made in example 11, the letter P is the absorption rate for the printing medium for water-based ink made in example 12, the letter Q is the absorption rate for the printing medium for water-based ink made in example 13, the letter R is the absorption rate for the printing medium water carrier water-based ink made in Example 14, S is the absorption rate for the water-based ink media made in Example 15, T is the absorption rate for the water-based ink media made in Example 16, U is the absorption rate for the media for the water-based ink made in Example 17, V is the absorption rate for the water-based ink media made in Example 18, and W is the absorption rate for the water-based ink media made in Example 19.

1. A recording medium for water-based ink, comprising a paper base and an ink receiving layer formed on the surface of the paper base, where the ink receiving layer contains a porous layer including an inorganic pigment, and also a substance reactive with the coloring matter of the ink, and where on the printed the media, printing is carried out with water-containing ink, which includes the coloring matter of the ink, characterized in that a drop of distilled water with a volume of 4 μl that has fallen on the surface of the ink-receiving layer is absorbed in the first stage of absorption at the first absorption rate V1 (μl / s) for one seconds after the fall, in the second uptake stage with a second uptake rate V2 (µl/s) for at least 2 s after the first uptake stage and in the third uptake stage following the second uptake stage with a third uptake rate V3 (µl /s), while the absorption of the drop at all, from the first to the third, stages of absorption satisfies the following relation:
00while the second absorption rate V2 (µl/s) is greater than 0.01 (µl/s) and less than 0.32 (µl/s), provided that the inflection point between the first and second absorption stages is a, the inflection point between the second and the third absorption stage is b, the end point of the third absorption stage is c, the amounts of liquid absorbed at points a, b and c are qa, qb and qc respectively, the time to reach points a, b and c is ta, tb and tc respectively, the amount of absorbed liquid qa at the inflection point a is not less than 1.3 µl and less than 2.0 µl, the amount of absorbed liquid qb at point b is not less than 2.0 µl and less than 2.5 µl.

2. The recording medium for water-based ink according to claim 1, wherein the inflection point a corresponds to a time of 0.5 seconds after the drop has fallen.

3. The recording medium for water-based ink according to claim 1, wherein the amount of liquid (qb-qa) absorbed in the second absorption step is not less than 0.3 µl and not more than 1.4 µl.

4. The recording medium for water-based ink according to claim 1, wherein the amount of liquid (qb-qa) absorbed in the second absorption step is not less than 0.5 µl and not more than 1.0 µl.

5. The recording medium for water-based ink according to claim 1, wherein the amount of absorbed liquid qa at the inflection point a is not less than 1.5 µl.

6. The recording medium for water-based ink according to claim 5, wherein the weight of the recording medium is not less than 180 g/m 2 and not more than 300 g/m 2 , and the inflection point b occurs within 8 seconds after the fall of the drop.

7. A print medium for water-based ink according to any one of claims 1 to 6, wherein the paper substrate has a Steckigt sizing degree of at least 5 seconds and at most 50 seconds.

8. The aqueous ink recording medium according to any one of claims 1 to 6, wherein the ink receiving layer has a pH B that satisfies the following relationship:
5<рН B ≤7.

9. The aqueous ink media according to claim 8, wherein the paper substrate has pH A and the ink receiving layer has pH B, satisfying the following relationship:
1<(рН B -рН A)<4.

10. A recording medium for water-based ink according to any one of claims 1 to 6, wherein the second absorption rate V2 (μl/s) is greater than 0.05 (μl/s) and less than 0.23 (μl/s).

11. A recording medium for water-based ink according to any one of claims 1 to 6, wherein the second absorption rate V2 (μl/s) is greater than 0.12 (μl/s) and less than 0.23 (μl/s).

12. A print medium for water-based ink, comprising a paper base, where the paper base is characterized by a Steckigt sizing degree of not less than 5 s and not more than 50 s, and an ink-receiving layer formed on the surface of the paper base, where the ink-receiving layer contains amorphous silicon oxide, an adhesive and a substance that reacts with the coloring matter of the ink, and characterized in that a drop of distilled water with a volume of 4 µl falling on the surface of the ink-receiving layer is absorbed in the first stage of absorption at the first absorption rate V1 (µl/s) for one second after the fall, in the second uptake stage with a second uptake rate V2 (µl/s) for at least 2 s after the first uptake stage and in the third uptake stage following the second uptake stage with a third uptake rate V3 (µl/s) c) within 8 s after the fall, while the absorption of the drop in these, from the first to the third, stages of absorption satisfies the following ratio:
0while the second absorption rate V2 (µl/s) is greater than 0.01 (µl/s) and less than 0.32 (µl/s), provided that the inflection point between the first and second absorption stages is a, the inflection point between the second and the third absorption stage is b, the end point of the third absorption stage is c, the amounts of liquid absorbed at points a, b and c are qa, qb and qc respectively, the time to reach points a, b and c is ta, tb and tc respectively, the amount of absorbed liquid qa at the inflection point a is not less than 1.5 µl and not more than 2.0 µl, the amount of liquid (qb-qa) absorbed in the second stage of absorption is not less than 0.3 µl and not more than 1.0 µl.

13. The aqueous ink recording medium according to claim 12, wherein the ink receiving layer has a pH B that satisfies the following relationship:
5<рН B ≤7,
the paper base has a pH A and the ink receiving layer has a pH B that satisfies the following relationship:
1<(рН B -рН A)<4,
the thickness of the ink receiving layer is not less than 25 µm and not more than 35 µm, the weight of the paper base and the ink receiving layer is in the range of not less than 180 g/m 2 to not more than 300 g/m 2 .

14. A recording medium for water-based ink according to claim 12 or 13, wherein the second absorption rate V2 (μl/s) is greater than 0.12 (μl/s) and less than 0.23 (μl/s).

15. A print medium for water-based ink printed with water-based ink containing an anionic colorant, wherein the surface of the print medium includes an ink-receiving layer that contains a porous layer containing an inorganic pigment and a dye-reactive substance. ink substance, characterized in that a drop of distilled water with a volume of 4 μl, which has fallen on the surface of the ink-receiving layer, is absorbed in the first stage of absorption with the first absorption rate V1 (μl/s) within one second after falling, in the second stage of absorption with the second rate absorption V2 (µl/s) for at least 2 s after the first absorption stage and in the third absorption stage following the second absorption stage, with a third absorption rate V3 (µl/s), while the droplet absorption on these, with the first according to the third, stages of absorption satisfies the following relation:
00while the second absorption rate V2 (µl/s) is greater than 0.01 (µl/s) and less than 0.32 (µl/s), provided that the inflection point between the first and second absorption stages is a, the inflection point between the second and the third absorption stage is b, the end point of the third absorption stage is c, the amounts of liquid absorbed at points a, b and c are qa, qb and qc respectively, the time to reach points a, b and c is ta, tb and tc respectively, the amount of absorbed liquid qa at the inflection point a is not less than 1.3 µl and not more than 2.0 µl, the amount of liquid (qb-qa) absorbed in the second stage of absorption is not less than 0.3 µl and not more than 1.0 µl.

16. The recording medium for water-based ink according to claim 15, wherein the second absorption rate V2 (μl/s) is greater than 0.05 (μl/s) and less than 0.23 (μl/s).

17. A recording medium for water-based ink according to claim 16, wherein the paper substrate has a Steckigt sizing degree of at least 5 seconds and at most 50 seconds.

18. Printing medium for water-based ink, comprising a paper base and an ink-receiving layer formed on the surface of the paper base, where the ink-receiving layer contains amorphous silicon oxide, an adhesive and a substance that reacts with the coloring matter of the ink, characterized in that a drop of distilled water 4 μl falling on the surface of the ink-receiving layer is absorbed in the first stage of absorption with the first absorption rate VI (μl/s) within one second after the fall, in the second stage of absorption with the second absorption rate V2 (μl/s) for, at least 2 s after the first absorption stage and in the third absorption stage following the second absorption stage, with a third absorption rate V3 (μl/s), while the absorption of the drop in these first to third absorption stages satisfies the following relationship :
00while the second absorption rate V2 (µl/s) is greater than 0.01 (µl/s) and less than 0.32 (µl/s), provided that the inflection point between the first and second absorption stages is a, the inflection point between the second and the third absorption stage is b, the end point of the third absorption stage is c, the amounts of liquid absorbed at points a, b and c are qa, qb and qc respectively, the time to reach points a, b and c is ta, tb and tc respectively, the amount of liquid absorbed qa at the inflection point a is not less than 1.3 µl and less than 2.0 µl, the amount of liquid absorbed qb at the inflection point b is greater than the amount of liquid absorbed at the first stage qa and less than 2.5 µl, the amount of liquid (qb -qa) absorbed in the second stage of absorption, not less than 0.3 µl and not more than 1.4 µl.

19. The recording medium for water-based ink according to claim 18, wherein the amount of liquid (qb-qa) absorbed in the second absorption step is not less than 0.38 µl and not more than 1.0 µl.

20. The recording medium for water-based ink according to claim 19, wherein the amount of absorbed liquid qa at the inflection point a is not less than 1.5 µl.

21. A recording medium for water-based ink according to claim 18, wherein the second absorption step takes place not earlier than 2.0 s and not later than 13.5 s after the fall of the drop.

22. The recording medium for water-based ink according to claim 21, wherein the time tc in the third absorption stage is up to 14.1 seconds after the drop has fallen.

23. A recording medium for water-based ink as claimed in claim 20, wherein the second absorption stage occurs up to 6.1 seconds after droplet fall, and the time tc to the end point of the third absorption stage is up to 8 seconds after droplet fall.

24. The recording medium for water-based ink according to claim 19, wherein the second absorption step occurs within or 9.5 seconds after the drop, and the time tc to the end point of the third absorption stage is up to 14.5 seconds after the drop.

25. A recording medium for water-based ink according to any one of claims 17 to 24, wherein the second absorption rate V2 (μl/s) is greater than 0.05 (μl/s) and less than 0.23 (μl/s).

26. The recording medium for water-based ink according to claim 23, wherein the second absorption rate V2 (μl/s) is greater than 0.12 (μl/s) and less than 0.23 (μl/s).

27. The recording medium for water-based ink according to claim 24, wherein the second absorption rate is greater than 0.05 (μl/s) and less than 0.09 (μl/s).

28. A method for determining absorption parameters of a print medium for water-based ink, where the print medium includes a paper base and an ink-receiving layer formed on the surface of the paper base, where the ink-receiving layer contains amorphous silicon oxide, an adhesive, and a substance that reacts with the coloring matter of the ink, where the method includes determining that:
a drop of distilled water with a volume of 4 µl falling on the surface of the ink-receiving layer of a recording medium for water-based ink is absorbed in the first stage of absorption at the first absorption rate VI (µL/s) within one second after falling, in the second stage of absorption at the second absorption rate V2 (μl/s) for at least 2 s after the first absorption stage and in the third absorption stage following the second absorption stage, with a third absorption rate V3 (μl/s);
that the second uptake rate V2 (μl/s) is greater than 0.01 (μl/s) and less than 0.32 (μl/s); and
determination of the inflection points a between the first and second absorption stages, b between the second and third absorption stages and the end point of the third absorption stage c, provided that the amounts of liquid absorbed at points a, b and c are equal to qa, qb and qc respectively, the time to reaching points a, b and c is ta, tb and tc, respectively, the amount of absorbed liquid qa at the first stage of absorption is not less than 1 μl and less than 2.0 μl, the amount of absorbed liquid qb at the second stage of absorption is greater than the amount of absorbed liquid qa by the first stage, and less than 2.5 μl, and the amount of liquid (qb-qa) absorbed in the second stage of absorption is not less than 0.3 μl and not more than 1.4 μl.

29. The method for determining ink absorption parameters of a recording medium for water-based ink according to claim 28, wherein the second absorption rate V2 (μl/s) is greater than 0.05 (μl/s) and less than 0.23 (μl/s).

30. The method for determining ink absorption parameters of a recording medium for water-based ink according to claim 28, wherein the weight of the paper base and the ink-receiving layer is in the range of not less than 180 g/m 2 to not more than 300 g/m 2 , and the second the uptake rate V2 (µl/s) is greater than 0.12 (µl/s) and less than 0.23 (µl/s).

The invention relates to the field of protection of banknotes, securities and documents and can be used in the manufacture of labels containing nitrogen-vacancy active centers in diamond nanocrystals, for applying them in the form of a substance to these objects as authentication of the latter

Printing Medium for Water-Containing Ink and Method for Determining Ink Absorption Parameters

Before purchasing large quantities of paper or specialty letterhead, make sure your supplier meets the media requirements outlined in the Printer Media Guide.

Some types of paper may meet all the requirements outlined in this chapter or the Printer Media Guide, but the print quality will still be unsatisfactory. This may be caused by inappropriate printing conditions or other external circumstances beyond HP's control (such as temperature and humidity that are not acceptable).

Problems may occur if you use paper that does not meet the specifications listed here or in the media specifications guide.

Unwanted paper types

The machine can print on various types of paper. Using paper that does not meet specifications may result in poor print quality and may cause paper jams.

Don't use too rough paper. Use paper with Sheffield smoothness between 100 and 250.

Do not use paper with cutouts or perforations, or paper other than standard 3-hole perforated paper.

Do not use non-uniform forms.

Do not use paper that has already been printed on or that has passed through a photocopier.

Do not use paper with a background image when printing a flood.

Do not use embossed paper or letterhead that has been screen printed.

Do not use paper that has a highly textured surface.

Do not use special powders or other materials designed to prevent printed forms from sticking together.

Do not use paper with a color coating applied after the paper is made.

Paper that can damage the device

In rare cases, paper can cause the device to fail. The following types of paper should be avoided as they may damage the machine:

Do not use paper with staples attached.

Do not use transparencies, labels, photo paper, or glossy paper designed for inkjet printers or other low temperature printers. Use only those media and or intended for the printer (where to order or order, how to make a request).

Do not use embossed or coated paper, or any other media that cannot withstand the fusing temperature of this machine. Do not use letterhead or paper printed with inks or inks that cannot withstand the temperature of the fuser.

Do not use media that releases hazardous contaminants, melts, bends, or discolours when exposed to the temperature of the fuser.

General media specifications

Envelopes

The design of the envelopes is essential. The fold lines on envelopes can be different not only within batches coming from different manufacturers, but even within a box from the same manufacturer. The quality of printing on envelopes depends to a large extent on the quality of the material from which the envelopes are made. When choosing envelopes, the following requirements must be taken into account.

Density. Envelope paper must not be heavier than 105 g/m2 (28 lb) or the paper may jam.

The form. Envelopes must be neatly folded before printing, allowing for curl up to 5 mm (0.2 in.). In addition, there must be no air in the envelopes.

Manufacturing quality. Envelopes should not have wrinkles, slits or other damage.

Temperature. You must use envelopes that can withstand the temperature and pressure of the machine.

Format. Only the following sizes of envelopes can be used.

Minimum: 76 by 127 mm (3 by 5 in.)

Maximum: 216 x 356 mm (8.5 x 14 in.)

Use only envelopes recommended for laser printers. Using other envelopes may damage the device. To prevent serious media jams when printing on envelopes, always use Tray 1 and the rear output bin. You can use the envelope for printing only once.

Envelopes with seams at both ends

Envelopes with seams at both ends have vertical seams instead of diagonal seams. It is very likely that these envelopes will wrinkle. Make sure the seam line reaches the corner of the envelope as shown below.

Acceptable Envelope Design

Invalid Envelope Design

Envelopes with adhesive strips or flaps

Envelopes with an adhesive strip covered with a protective film or with multiple fold-over seal flaps must use an adhesive that meets the temperature and pressure requirements of the device. Additional flaps and bands can cause kinks, wrinkles, and even fuser failure.

Margins on envelopes

The table below shows the typical address fields for #10 or DL ​​size envelopes.

Envelope storage

Proper storage of envelopes contributes to high-quality printing. Envelopes should be stored horizontally. Air remaining in envelopes causes air bubbles to form, which can cause envelopes to jam during printing.

Use only labels recommended for laser printers. Use of other labels may damage the device. To prevent serious media jams when printing on labels, always use Tray 1 and the rear output bin. A label page can only be printed once. Reprinting on part of the page is also not allowed.

Label shape

When choosing a label, consider the workmanship of each of its components.

Adhesive backing: The adhesive backing must be resistant to temperatures up to 200° C (392° F) during printing.

Location. Use only labels that do not have exposed adhesive backing between labels. Labels may peel off the liner if there are exposed areas on the liner. This results in hard-to-remove media jams.

Curl: Sheets of labels to be printed should not be more than 5 mm (0.2 in.) off-flat.

Manufacturing quality. Do not use labels with folds, bubbles, or other signs of peeling.

Select envelopes in the printer driver.

Transparencies

The transparencies used in the device must be able to withstand temperatures of 200° C (392° F), the maximum temperature that the printer will experience during printing.

Use only transparencies recommended for laser printers. Using other transparencies may damage the device. To prevent serious media jams when printing on transparencies, always use Tray 1 and the rear output bin. You can only use transparencies for printing once. Reprinting on the transparencies section is also not allowed.

Select transparencies in the printer driver.

Card stock and heavy media

The device allows you to print various types of cards from the input tray, including index cards and postcards. Some types of cards feed into the machine better than others. This is because their structure is more suitable for the material feed mechanism of a laser printer.

For optimal performance, do not use paper heavier than 199 g/m2. Paper that is too thick can cause problems with the feed mechanism, uneven stacking in the tray, paper jams in the machine, poor toner fusing, poor print quality, or excessive mechanical wear.

Printing on thicker paper is possible. To do this, the tray must not be loaded to the maximum mark, and the paper must be Sheffield-type smoothness from 100 to 180 units.

In the software application or printer driver, select Heavyweight (106g/m2 to 163g/m2; 28lb to 43lb bond) or Card Stock (135g/m2 to 216g/m2; 50 to 80 lb. bond paper) or print from a tray that is set to use thick paper. Because this setting affects all jobs, you should reset the machine to its original settings after printing is complete.

Card design

Smoothness: 135 to 157 gsm cards should have a Sheffield smoothness of 100 to 180 gsm. 60 to 135 gsm cards must have Sheffield smoothness of 100 to 250 gsm.

The form. The stack of cards should lie horizontally. The bulge must not exceed 5 mm.

State. Do not print cards with wrinkles, tears, or other defects.

Card printing

Set the margins: at least 2 mm from the edges.

For card stock, use Tray 1 (135 g/m2 to 216 g/m2; 50 to 80 lb cover).

Use only cards recommended for laser printers. Using other cards may damage the device. To prevent serious media jams when printing on card stock, always use Tray 1 and the rear output bin.

Letterheads and preprinted forms

Letterhead is a high quality paper that is mostly watermarked, sometimes with cotton fiber, comes in a variety of colors and matches the paper used to make envelopes. Letterheads are printed on various types of paper, both high-quality and recycled.

Most manufacturers supply a wide range of laser-optimized papers. They make sure their paper is great for laser printing. Some types of paper with a rough surface, such as drawing paper, laid paper, or canvas, may require a special fuser mode that is available on some printer models to achieve acceptable toner fixation.

When printing on laser printers, slight variations in quality may occur. These deviations are invisible when printed on plain paper. However, they can be seen when printing on preprinted paper because the lines and margins are already placed on the page.

To avoid problems when using preprinted paper, embossed designs, and letterhead, follow these guidelines:

Avoid using forms printed with low temperature inks (used in some types of thermography).

Use preprinted and letterhead that has been printed using lithography and engraving.

Use letterhead printed with heat-resistant inks that will not melt, vaporize, or bleed when heated to 200°C for 0.1 second. Usually oxidized and oil-based paints meet these requirements.

When preprinting letterhead, make sure that the moisture content of the paper has not changed and that no materials are used that change the electrical and physical properties of the paper. Forms should be stored in a moisture-proof environment to prevent dampening.

Avoid processing preprinted paper that has already been used or has been coated in any way.

Do not use embossed paper or embossed letterhead.

Do not use paper that has a textured surface.

Do not use paper that has spray on the surface or other materials that prevent letterhead from sticking together.

To print a one-sided cover letter on letterhead and then a multipage document, load letterhead face up in Tray 1 and plain paper in Tray 2. The machine will automatically start printing on paper from Tray 1.

Select the correct fuser mode

The device automatically adjusts the fuser mode according to the media type set for the tray. Thick paper (such as card stock) requires a high fuser setting to better bond the toner to the paper, while transparencies require a lower fuser setting to prevent damage to the machine. Generally, the default setting provides the best performance for most types of print media.

The fuser mode can only be changed if the media type is set for the tray being used. Once a media type has been set for a tray, the fuser mode for that type can be changed from the Administration menu under the Print Quality submenu on the product control panel.

Using the High 1 or High 2 fuser setting improves the adhesion of the toner to the paper, but may cause other problems such as excessive paper curl. If the fuser is set to High 1 or High 2, the machine may print at a slower speed. The following table lists the fuser mode settings that are most appropriate for each type of supported print media.

To reset the fuser modes to their default modes, open the Administration menu on the device control panel. Click Print Quality, then Fuser Options, and then Restore Options.

Selecting print media

This machine supports a variety of media such as cut-sheet paper with up to 100% recycled fiber content; envelopes; labels; transparencies and custom size paper. Weight, composition, grain, and moisture content are critical factors that determine device performance and print quality. Paper that does not meet the guidelines specified in this guide may cause the following problems:

Decreased print quality

To frequent paper jams

Premature wear of the device and the need for repair

Using media that does not meet HP specifications may damage the device and require repair. HP warranties and service agreements do not cover such repairs.

Supported Media Sizes

Supported media types

Loading media

Envelopes, labels, transparencies, and other special media can only be loaded in Tray 1. Tray 2 and optional Tray 3 can only be loaded with paper.

Placing a Document on the Scanner Glass

Use the scanner glass to copy, scan, or fax small, light (less than 60 g/m2 or 16 lb.) custom items such as receipts, newspaper clippings, photographs, and old or worn documents.

Place your document face down on the scanner glass with the top left corner of the document aligned with the top left corner of the scanner glass.

Use the ADF to copy, scan, or fax a document up to 50 pages (depending on page thickness).

1. Load the document into the ADF face up so that the document is fed from the beginning.

2. Push the stack into the automatic document feeder until it stops.

3. Adjust the media guides against the edges of the media.

Loading Tray 1 (MP Tray)

Tray 1 holds up to 100 sheets of paper, 75 transparencies, 50 sheets of labels, or 10 envelopes.

1. Open Tray 1 by lowering the front cover.

2. Pull out the plastic tray extension. If the media you are loading is longer than 229 mm (9 inches), you must also open the optional tray extension.

3. Slide the media width guides slightly wider than the media width.

4. Place the media in the tray (short edge first, face up). The media should be centered in the tray using the media guides. The height of the media stack must not exceed the height limiters located on the media guides.

5. Slide the guide tabs inward on both sides until they touch the media stack, but without the clip. Make sure the media is loaded under the tabs on the width guides.

Adding media to Tray 1 during printing is not allowed. This may cause a media jam. Do not close the front door while printing is in progress.

Tray 1 operation setting

The MFP can be set to print from Tray 1 if that tray is loaded, or to print from Tray 1 only if you want to print on a special type of media.

Parameter

Description

The Tray 1 Size setting for Tray 1 is set to Any Size.

Tray 1 Type, which specifies the type of Tray 1, is set to Any Type

Typically, the MFP draws media from Tray 1 first if that tray is open or loaded. If Tray 1 does not always have media, or if Tray 1 is used for manual media feed only, the Tray 1 Size and Type settings should be set to the default values. The default setting for these Tray 1 options is Any. To change the type and size of Tray 1, touch the Trays tab in Status, and then touch Change.

Tray 1 Size and Tray 1 Type are not Custom. forms. and any type

The MFP does not distinguish Tray 1 from other trays, so it does not look for media in Tray 1, but instead looks directly at the tray that contains the media that matches the software settings.

Using the printer driver, you can select media from any tray (including Tray 1) by type, size, or source.

Loading Tray 2 and Optional Tray 3

Trays 2 and 3 can only be loaded with paper.

1. Remove the tray from the machine and remove all paper.

2. Press the bar on the rear paper length guide and adjust it so that the arrow matches the size of the paper you are loading. The guide should click into place.

3. Adjust the media side guides so that the arrow matches the paper size you are loading.

4. Place the paper in the tray and make sure it lies flat and snug against all four corners of the tray. Do not load paper above the height tabs on the paper length guide at the back of the tray.

5. Push down on the paper to lock the metal paper pressure plate into place.

6. Slide the tray into the machine.

Loading special media

To get the best print quality, you need to set the correct media type in the printer driver settings. When using some types of media, the print speed of the machine slows down.

Note In the Windows printer driver, set the media type on the Paper tab by selecting it from the Type drop-down list.

In the Macintosh printer driver, set the media type in the Printer Features pop-up menu by selecting it from the Media Type drop-down list.

Maximum amount of media that can be loaded in Tray 2 or optional Tray 3

Print job management

When a job is sent to the printer, the printer driver controls the selection of the tray from which media is fed into the printer. By default, the printer automatically selects a tray, but you can also select a specific tray based on three user-specified options: Source, Type, and Size. These options are available in the Application Setup, Printing, or printer driver dialog boxes.

Instructs the printer to take paper from a user-defined tray. The printer will attempt to print from this tray, no matter what type or size of media is loaded in it. To start printing, load media of the correct type and size for the print job in the selected tray. After loading media in the tray, the printer will start printing. If the printer does not start printing:

Make sure the tray configuration matches the size and type of print job.

Press OK to have the printer start printing from another tray.

Type or Size

Instructs the printer to use paper or print media from the first tray loaded with media of the selected type or size. Always specify the Type setting for special print media such as labels or transparencies.

Selecting output bins

The multifunction printer has two output bins where finished print jobs are received.

Top bin (feed face down). This bin, located on the top of the MFP, is the default. Finished jobs enter this bin face down.

Rear output bin (face-up feed). This bin, located on the back of the MFP, receives finished jobs face up.

When outputting to the rear bin, duplex printing is not possible.

Printing with the document output to the top output bin

1. Make sure the rear output bin is closed. If the rear output bin is open, the printer outputs documents to this bin.

2. When printing on long media, open the top output bin support.

Printing with the document output to the rear output bin

When Tray 1 and the rear output bin are used at the same time, the paper will pass straight through the print job. The straight paper path avoids folds.

1. Open the rear output bin.

2. Pull out the bin extender when printing on long media.

3. Send a print job from the computer to the machine.

What did the first man know? How to kill a mammoth, bison or catch a wild boar. In the Paleolithic era, there were enough walls in the cave to record everything studied. The entire cave database would fit on a modest megabyte flash drive. In the 200,000 years of our existence, we have learned about the African frog genome, neural networks, and we no longer draw on rocks. Now we have disks, cloud storage. As well as other types of storage media capable of storing the entire library of Moscow State University on one chipset.

What is a storage medium

A storage medium is a physical object whose properties and characteristics are used to record and store data. Examples of storage media are films, compact optical discs, cards, magnetic disks, paper, and DNA. Storage media differ according to the principle of recording:

• printed or chemical with paint applied: books, magazines, newspapers;
• magnetic: HDD, floppy disks;
• optical: CD, Blu-ray;
• electronic: flash drives, solid state drives.

Data storages are classified according to the waveform:

• analog, using a continuous signal for recording: audio compact cassettes and reels for tape recorders;
• digital - with a discrete signal in the form of a sequence of numbers: floppy disks, flash drives.

The first media

The history of recording and storing data began 40 thousand years ago, when Homo sapiens got the idea to make sketches on the walls of their dwellings. The first rock art is located in the Chauvet cave in the south of modern France. The gallery contains 435 drawings depicting lions, rhinos and other representatives of the Late Paleolithic fauna.

To replace the Aurignacian culture in the Bronze Age, a fundamentally new type of information carrier arose - tuppum. The device was a clay plate and resembled a modern tablet. Recordings were made on the surface using a reed stick - a stylus. To prevent labor from being washed away by rain, tuppums were burned. All tablets with ancient documentation were carefully sorted and stored in special wooden boxes.

The British Museum has a tuppum containing information about a financial transaction that took place in Mesopotamia during the reign of King Assurbanipal. An officer from the prince's retinue confirmed the sale of the slave Arbela. The tablet contains his personal seal and records of the progress of the operation.

Kipu and papyrus

From the III millennium BC, papyrus began to be used in Egypt. Data is recorded on sheets made from the stems of the papyrus plant. The portable and lightweight form of storage media quickly supplanted its clay predecessor. Not only the Egyptians write on papyrus, but also the Greeks, Romans, and Byzantines. In Europe, the material was used until the 12th century. The last document written on papyrus is a papal decree of 1057.

Simultaneously with the ancient Egyptians, at the opposite end of the planet, the Incas invented the kippah, or "talking knots." Information was recorded by tying knots on spinning threads. Kipu kept data on tax collections, population. Presumably, non-numeric information was used, but scientists have yet to unravel it.

Paper and punch cards

From the 12th century to the middle of the 20th century, paper was the main data storage. It was used to create printed and handwritten publications, books, and mass media. In 1808, punched cards began to be made from cardboard - the first digital storage media. They were sheets of cardboard with holes made in a certain sequence. Unlike books and newspapers, punched cards were read by machines, not by people.

The invention belongs to an American engineer with German roots Herman Hollerith. For the first time, the author applied his offspring to compile mortality and birth statistics at the New York Board of Health. After trials, punched cards were used for the 1890 US Census.

But the idea of ​​punching holes in paper to record information was far from new. Back in 1800, Frenchman Joseph-Marie Jacquard introduced punched cards to control a loom. Therefore, the technological breakthrough was the creation by Hollerith not of punched cards, but of a tabulation machine. This was the first step towards automatic reading and calculation of information. Herman Hollerith's TMC tabulating machine company was renamed IBM in 1924.

OMR cards

They are sheets of thick paper with information recorded by a person in the form of optical marks. The scanner recognizes marks and processes the data. OMR cards are used to compile questionnaires, tests with optional choice, bulletins and forms that must be completed manually.

The technology is based on the principle of compiling punched cards. But the machine does not read through holes, but bulges, or optical marks. The calculation error is less than 1%, so government agencies, examining bodies, lotteries and bookmakers continue to use OMR technology.

Perforated tape

A digital storage medium in the form of a long paper strip with holes. Perforated ribbons were first used by Basile Bouchon in 1725 to control a loom and mechanize the selection of threads. But the tapes were very fragile, easily torn and at the same time expensive. Therefore, they were replaced by punched cards.

Since the end of the 19th century, punched tape has been widely used in telegraphy, for entering data into computers of the 1950s-1960s, and as carriers for minicomputers and CNC machines. Now bobbins with wound punched tape have become an anachronism and have sunk into oblivion. Paper media have been replaced by more powerful and voluminous data storages.

Magnetic tape

The debut of magnetic tape as a computer storage medium took place in 1952 for the UNIVAC I machine. But the technology itself appeared much earlier. In 1894, Danish engineer Voldemar Poulsen discovered the principle of magnetic recording while working as a mechanic for the Copenhagen Telegraph Company. In 1898, the scientist embodied the idea in an apparatus called the "telegraph".

A steel wire passed between the two poles of an electromagnet. Recording of information on the carrier was carried out by means of non-uniform magnetization of electric signal oscillations. Voldemar Poulsen patented his invention. At the 1900 World Exhibition in Paris, he had the honor of recording the voice of Emperor Franz Joseph on his device. The exhibit with the first magnetic sound recording is still kept in the Danish Museum of Science and Technology.

When Poulsen's patent expired, Germany began to improve magnetic recording. In 1930 steel wire was replaced by flexible band. The decision to use magnetic stripes belongs to the Austrian-German developer Fritz Pfleimer. The engineer came up with the idea of ​​coating thin paper with iron oxide powder and recording through magnetization. Using magnetic film, compact cassettes, video cassettes and modern storage media for personal computers were created.

HDDs

Winchester, HDD or hard drive is a hardware device with non-volatile memory, which means that information is completely saved, even when the power is turned off. It is a secondary storage device consisting of one or more plates on which data is recorded using a magnetic head. HDDs are located inside the system unit in the drive bay. They are connected to the motherboard using an ATA, SCSI or SATA cable and to the power supply.

The first hard drive was developed by the American company IBM in 1956. The technology was used as a new type of storage media for the IBM 350 RAMAC commercial computer. The abbreviation stands for "method of random access to accounting and control."

To accommodate the device at home, it would take an entire room. Inside the disc were 50 aluminum plates, 61 cm in diameter and 2.5 cm wide. The size of the storage system was equal to two refrigerators. Its weight was 900 kg. RAMAC capacity was only 5MB. Ridiculous number today. But 60 years ago it was regarded as the technology of tomorrow. After the announcement of the development, the daily newspaper of the city of San Jose released a report titled "Machine with Super Memory!".

Dimensions and capabilities of modern HDDs

A hard drive is a computer storage medium. Used to store data, including images, music, videos, text documents, and any content created or downloaded. In addition, contain files for the operating system and software.

The first hard drives contained up to several tens of MB. Constantly evolving technology allows modern HDDs to store terabytes of information. That's about 400 medium-length films, 80,000 songs in mp3 format, or 70 Skyrim-like computer role-playing games on one device.

Diskette

The floppy, or floppy disk, is a storage medium created by IBM in 1967 as an alternative to the HDD. Floppy disks were cheaper than hard drives and were intended for storing electronic data. Early computers did not have a CD-ROM or USB. Floppy disks were the only way to install a new program or backup.

The capacity of each 3.5-inch floppy was up to 1.44 MB, when one program "weighed" at least one and a half megabytes. Therefore, the version of Windows 95 appeared immediately on 13 DMF diskettes. The 2.88 MB floppy disk appeared only in 1987. This electronic storage medium existed until 2011. Modern computers do not have floppy drives.

Optical media

With the advent of the quantum generator, the popularization of optical storage devices began. Recording is carried out by a laser, and data is read out due to optical radiation. Examples of storage media:

• Blu-ray discs;
• CD-ROM discs;
• DVD-R, DVD+R, DVD-RW and DVD+RW.

The device is a disk covered with a layer of polycarbonate. There are micro-pits on the surface, which are read by the laser during scanning. The first commercial laser disc appeared on the market in 1978, and in 1982 the Japanese company SONY and Philips launched CDs. Their diameter was 12 cm, and the resolution was increased to 16 bits.

Electronic media in the CD format was used exclusively for the reproduction of sound recordings. But at the time, it was cutting-edge technology, for which Royal Philips Electronics received an IEEE award in 2009. And in January 2015, the CD was awarded as the most valuable innovation.

In 1995, digital versatile discs or DVDs appeared, becoming the next generation of optical media. To create them, a different type of technology was used. Instead of red, the DVD laser uses shorter infrared light, which increases the storage capacity. Dual layer DVDs can store up to 8.5 GB of data.

Flash memory

Flash memory is an integrated circuit that does not require constant power to store data. In other words, it is a non-volatile semiconductor computer memory. Memory devices with flash memory are gradually conquering the market, displacing magnetic media.

Advantages of Flash technology:

• compactness and mobility;
• large volume;
• high speed of work;
• low power consumption.

Flash storage devices include:

• USB flash drives. This is the simplest and cheapest storage medium. Used for multiple recording, storage and transmission of data. Sizes range from 2 GB to 1 TB. Contains a memory chip in a plastic or aluminum case with a USB connector.
• Memory cards. Designed to store data on phones, tablets, digital cameras and other electronic devices. They differ in size, compatibility and volume.
• SSD. Solid state drive with non-volatile memory. This is an alternative to a standard hard drive. But unlike hard drives, SSDs do not have a moving magnetic head. Due to this, they provide quick access to data, do not emit squeaks, like HDDs. Of the shortcomings - the high price.

Cloud storage

Online cloud storages are modern information carriers, which are a network of powerful servers. All information is stored remotely. Each user can access data at any time and from anywhere in the world. The disadvantage is complete dependence on the Internet. If you don't have a network or Wi-Fi connection, you won't be able to access your data.

Cloud storage is much cheaper than its physical counterparts and has a large volume. The technology is actively used in the corporate and educational environment, development and design of computer software web applications. On the cloud, you can store any files, programs, backups, use them as a development environment.

Of all the listed types of storage media, cloud storage is the most promising. Also, more and more PC users are moving from magnetic hard drives to solid state drives and flash media. The development of holographic technologies and artificial intelligence promises the emergence of fundamentally new devices that will leave flash drives, SDDs and disks far behind.

The invention relates to a printing medium and a method for its manufacture. The print medium contains a partial area with a transparent anisotropic layer, which is applied by printing and/or embossing tools to the layer-oriented structure. The carrier also contains a partial area with colorless embossing and/or unembossed, and/or embossed with a standard optical isotropic transparent varnish, while all partial areas, when viewed with the naked eye, regardless of the viewing angle, exhibit an optical image indivisible over partial areas. The proposed invention increases the degree of protection of the relevant documents against forgery. 2 n. and 8 z.p. f-ly, 2 ill.

Drawings to the RF patent 2345899

The invention relates to a printed medium, in particular labels, tax stamps, information or data carriers, entrance tickets, electronic payment cards, etc., and to a method for manufacturing such a printed medium.

It is known from the prior art to use a print medium, for example, to protect and authenticate any products, such as software products, payment cards, etc. Here, it is known, among other things, to use embossed images, also in the form of colorless embossing or in combination with embossed holograms, which, with difficult to falsify.

In the description of the application before examination DE 198 45552 A1 describes a print medium, such as, for example, securities, bank notes, identity cards, etc., provided with embossing in a predetermined area. At least part of the embossing is in the form of an inclined plane. Additionally, the region of the printed medium on which the embossing is performed is provided with at least one layer of ink or a multi-layer ink coating, the optical perception of which varies due to the inclined plane depending on the viewing angle, so as to make the embossing more distinguishable to the observer depending on the viewing angle. from the viewing angle.

All prior art print media have the disadvantage that the protection of the product is immediately visible to the naked eye, since the print media is sharply different from the background, respectively, the embossing on the print media is sharply different from the rest of the surface of the print media. The counterfeiter immediately understands that in order to counterfeit a product, it is necessary to counterfeit only a certain print medium. Counterfeiting of such printed media can be done so professionally that it is somewhat difficult for both the uninformed person and the skilled person to distinguish the counterfeit product from the genuine product.

The objective of the invention is to create such a printing medium and a method for its manufacture, which, when viewed with the naked eye, does not reveal the difference in individual areas, respectively, during a simple inspection, a protective embossed image (overprint) cannot be detected, so that the protection of the product, for example, cannot be recognized on the printing medium .

Due to the implicit recognition of the security of the product on such a print medium, counterfeiting is much more difficult for a counterfeiter, but at the same time, it is possible to immediately and simply detect a counterfeit without a sign according to the invention.

This problem is solved according to the invention in that the print medium is at least partially provided with a transparent anisotropic layer, in particular an optically colorless birefringent layer, in particular deposited on a layer-oriented structure.

Such a print medium can be made in such a way that at least one partial area of ​​the print medium having at least one layer-oriented structure is printed by printing an anisotropic layer, in particular a birefringent layer, for example, from nematogenous liquid crystals. Smectic and chirally nematic liquid crystals can also be used.

In contrast to the prior art, for example, according to the description of the application before the examination DE 198 45552 A1, the overprint or embossing made by the method in accordance with the invention is not immediately conspicuous and cannot be detected or, accordingly, cannot be easily detected by the naked eye, since the anisotropic layer is transparent, preferably colorless, and therefore the optical perception is created essentially by the print medium that is viewed through the layer, i.e. by its color and structural representation.

In this case, there is no viewing angle-dependent color effect, and difficult-to-make inclined planes that provide a color effect depending on the viewing angle may, but need not be present. Moreover, according to the invention, it is an overprint, which also means an embossing, which, without auxiliary means, in particular optical, is in no way visually or tactilely distinguishable from colorless embossing or embossing based on commercially available optically isotropic transparent varnishes. In this way, latent information can be integrated or presented in the overprint, which is revealed through differences between the anisotropic layer and other areas that become optically apparent, respectively also through differences within the anisotropic layer.

The invention can be used, for example, when printing documents that require security, such as, for example, bank notes, securities, credit cards and identity cards. Here, the print medium itself can already be a protected product, as is the case, for example, with banknotes or credit cards, or the print medium is applied as an additional security feature or the print medium in the form of a so-called security stamp ( tag) can be hung on or attached to any product.

The transparent anisotropic layer has, for example, optical polarizing effects which cannot be perceived, for example, by the naked eye, but which can be detected by using auxiliary means, for example, when it comes to the birefringence property, by means of a polarizing filter of a linear or circular type, in particular, when such an aid is used, they may become visible to the naked eye.

Particularly preferred can be the use of liquid crystals, such as nematic liquid crystals, respectively including varnishes, which contain such liquid crystals and, when overprinted or embossed, provide such a liquid crystal coating on a print medium as an anisotropic birefringent layer. Such radiation-curable liquid crystal mixtures are available, for example, from Merck KGaA. These mixtures are practically invisible when applied to a printing medium, but on a suitable background, such as a reflective printing medium, and with the use of auxiliary means in the form of linear or circular polarizers, they provide pronounced visual optical effects.

Such a liquid crystal layer can be applied, for example, by embossing, preferably on a metallic print carrier with a specular gloss, whereby the resulting coatings, for example with a nematic, can be permanently fixed by a suitable method, for example by irradiation with UV light.

When viewed with the naked eye, these embossed overprints do not differ in any way from the corresponding colorless embossings or those embossed overprints made with commercially available clear lacquers. Consequently, they have the usual three-dimensional images caused by the play of chiaroscuro, but even by creating an additional contrast or a color effect dependent on the viewing angle, they do not in any way make the embossing more optically clear. The difference cannot be detected even by touch.

And only when viewed with a linear or circular polarizer, embossed overprints obtained using nematic mixtures become more or less optically distinguishable, for example, due to the brilliance of paints. In this case, color images can additionally depend to a large extent on the (angle) position of the polarizer.

Differences present can be detected not only by the eye of the observer, but also by machine, for example by means of detectors for different directions of polarization of the reflected light, so that automatic control of the printing medium according to the invention is also possible.

The reason for this behavior of liquid crystal components is their spatial orientation, which in turn is largely due to the forces acting during the embossing process, in particular shear forces, as well as the corresponding microstructures of the printing media or embossing tools.

Therefore, when dividing an embossed image into various spatially delimited (partial) areas and when participating in the creation of an embossed image, forces orienting in separate areas that differ in their direction from each other, or in the case of structuring certain specific areas of a print medium or embossing tools, respectively, in different directions, an embossed image is created, the areas of which, when viewed with a polarizer, are distinguished by various optical effects.

The embossed overprints according to the invention are particularly characterized in that, in the presence of colorless embossings or embossings based on commercially available clear lacquers, they are not visible to the naked eye. But in reality, they offer optical information that becomes visible or can be detected, for example, using a polarizer. Therefore, the invention can be used in overprints to protect, for example, securities, bank notes and credit cards, respectively, to increase the security against forgery of the respective documents.

Thus, the print medium preferably comprises, in addition to at least one partial region with an anisotropic layer, at least one partial region with inkless embossing and/or one uncoated relief region and/or at least one partial region with a commercially available optically isotropic clearcoat.

The printed or embossed structures according to the invention can be produced particularly easily, for example by modified flexographic printing. In this case, the rolling of a rigid plate, for example, with a hardness D of about 60-70 Shore, is carried out on a preferably reflective wear-resistant deformable print medium, respectively, the printing material, while the pressing cylinder is equipped with an elastic rubber panel, for example, with a hardness A of about 50-60 Shore Shore.

The depth of embossing is controlled by increasing the pressing pressure. Additionally, for example, printed or embossed structures can be obtained by varying the thickness of the plate in the same print area with different embossing depths. Depending on whether printing is carried out with a printing medium using a plate, and if so, either colorless embossings are obtained, or embossings are obtained, which are covered, for example, with isotropic varnishes or especially important in this regard, for example, nematic liquid crystal films with optical birefringence.

The latter are based, for example, on nematogenic liquid crystal mixtures, which are manufactured, for example, by Merck KGaA and can be used, for example, in the form of their melts at a temperature of about 60-70° C. or in the form of their solutions in organic solvents.

Further, the manufacture of the embossing according to the invention can be carried out, respectively, with any embossing tool. It can be carried out in relief, for example by intaglio printing, in which case the embossed structures are engraved in a known manner on a metal plate. Patent publication WO 97/48555, for example, describes an electronic method for manufacturing this kind of intaglio plates. During the printing process, the print material is pressed into the recesses of the engraved metal plate and thus stably formed. In order to obtain a colorless embossing during the printing process, these printing plates are not filled with a printing medium, but are only used to form, that is, emboss on the printing material.

Regardless of whether a deep embossing or a raised embossing is produced in this way, it is not possible for an observer to distinguish, for example, a colorless embossing from an embossing using commercially available (optically isotropic) clearcoats or from an embossing using non-matogenic liquid crystal mixtures. The observer sees rather a single embossed structure, which, as a result of the play of chiaroscuro, transmits ordinary three-dimensional optical images.

However, as a result of, for example, the miniaturization and intersection of the individual sealed areas by multiple sealing, a significant microstructure is obtained, which is difficult to fake and which is revealed in the form of various viewing angle-dependent optical effects only when viewed with a linear or circular polarizer.

In typical practice, when a silvery, unstretched specular gloss polyethylene film is embossed, for example, as a print medium using a nematogenic liquid crystal melt at 60°C, an observer using a linear polarizer at the 0° position only sees embossed areas in blue, covered with nematic liquid crystal film. All other regions do not differ from how they would be considered without a polarizer. When the polarizer is rotated 45°, the blue color of the image changes to yellow-red.

Similar color images are seen when the embossed print is analyzed with a circular polarizer. Here the color images change depending on the position of the polarizer, for example between brilliant gold and brilliant silvery blue. At the same time, there are also cases when, depending on the position of the polarizer, the colors do not undergo significant changes, or there are cases when, not every 45°, but, in particular, every 90°, the color changes only slightly between, for example, close to dark brown and close to light brown.

In general, this (dynamic) color behavior depends on a variety of factors, which include, for example, the properties of the print media, the printing method used, the transition and wetting property (Verlaufs- und Benetzungseigenschaft) of the liquid crystal ink, as well as the thickness, uniformity and microstructure of the resulting liquid crystal films.

In general, nematic films, for example, appear much more reflective when viewed with a circular polarizer than when using a linear polarizer. Changing the viewing angle does not in any way affect the resulting color image.

A particular embodiment of the method occurs when, for example, the aforementioned modified flexographic printing method or similar methods are used, which require the application of force during the embossing process, such as shearing force, on (nematogenous) liquid crystal films and embossing tools of which are structured in such a way that the microscopic orientation components of the obtained liquid crystal film is supported in the preferred direction.

If, for example, when using a non-matogenic liquid crystal mixture, the first embossing pass is followed by rotation of the image by an angle of preferably 45°, and then another pass follows, a two-color embossed image is presented to the observer when analyzed with a linear or circular polarizer. Multicolor embossing becomes possible when the full range between possible color images is used.

The pressing pressure and therefore the depth of the embossing can also be reduced at will so that the embossed structures are no longer visible to the naked eye, but the orientation of the liquid crystals is nevertheless retained, resulting in at least the corresponding color images when using a polarizer. .

For all embodiments according to the invention, it is essential that an anisotropic layer, in particular a layer with birefringence, for example, from nematogenous liquid crystals, in any printing method, is applied to at least one partial area of ​​the print medium having at least one structure with layer orientation.

Through the structure, the liquid crystals of the anisotropic liquid crystal layer can be acted upon in at least one direction by a force which leads to the alignment of the liquid crystals, in particular along the respective acting force.

Before or during printing of the anisotropic layer, one or more of these structures may be applied to the area to be printed on the print medium. Therefore, the print media used here can be supplied with such a structure already prepared or provided with such a structure only in the printing press, for example, during the application of the printing medium.

The origin and type of structure is essentially irrelevant, since they have the property of promoting the layered orientation of the anisotropic layer, that is, for example, the crystalline orientation of liquid crystals. Therefore, the print medium can be provided with a mechanical structure and/or an electrostatic structure or a potential pattern, i. e. distribution of charges in accordance with the transmitted optical picture. Separate orientation layers can also be applied in front of the liquid crystal layer. Changes or targeted alignments of the crystal orientation can also be effected by local heating of the deposited liquid crystal layer or by applying electric and/or magnetic fields.

Other forms of implementation of the method, for example, the production of a printing medium according to the invention, concern, for example:

Making positive and negative embossing on the same image (print),

Improvements in optically anisotropic or multicolored print media by the method according to the invention,

The use of pre-embossed printing media with predetermined and locally defined orientation directions of various kinds for mesogenic systems,

Overprinting or applying on pre-embossed printing media also holographic structures etc., for example, produced by injection molding or other methods of forming relief structures, for example, using nematic liquid crystal mixtures, in this case, in particular, the structuring of embossed areas or reliefs can contribute orientation of textures of optically anisotropic liquid crystal films,

Production of different, thick, optically anisotropic liquid crystal films on the same embossed image, resulting in different color effects,

Applying an additional transparent, optically isotropic or anisotropic top coat, film, etc., for example, to protect against scratches or increase the security of the embossing against counterfeiting,

Post-embossing of partially or fully cured, optically anisotropic, e.g. nematic liquid crystal films,

Embossing overprints on transparent print media and overprinting of the reverse side of these print media treated in this way, e.g. with reflective inks,

Overprints or coatings in the first step of the film substrate, preferably with a fully cured nematic liquid crystal film, the manufacturing process parameters being controlled such that only one certain small but sufficient cohesion is created between the film substrate and the liquid crystal film.

The transfer of certain sections of the liquid crystal film in a second step onto a print medium by treating the reverse side of a suitably printed or coated film substrate with appropriate embossing tools, this process being possible at room temperature, as well as at lower or higher temperatures, and also under the influence of only very little embossing effort. According to the method of manufacture, a printing medium is preferred that is deformable, has increased adhesion relative to the film substrate, and is capable of reflecting light in such a way that the optical effects according to the invention become visible with the help of a polarizer.

Examples of implementation and advantages of the invention are explained on the basis of figures 1a, 1b, 1c and 2a, 2b, 2c. They are not drawn to scale, but only represent color diagrams and serve only to illustrate the invention.

In FIG. 1a shows schematically an embossing according to the invention on a silver printing medium with a specular sheen and a simplified color image that can be seen without an optical aid. Essentially only the embossed structure is visible, but no color differences are seen between the inkless embossing areas BP without any lacquer layer, the embossing P+LC with a liquid crystal layer, the P+KL embossing with an isotropic clear lacquer, and the non-embossing LC area including only a liquid crystal layer.

In FIG. 1b shows the same embossing according to the invention as in FIG. 1, on a silver print medium with a specular sheen and simplified as an example, a color image distinguishable with a linear polarizer in the 0° position. Here, color differences are observed based on the orientation of the crystals between the embossed P+LC region and the non-embossed LC region. This area is marked with a bold line.

In FIG. 1c shows the same embossing according to the invention as in FIG. 1a, on a silver print medium with a specular sheen and a simplified representation of a color image distinguishable with a linear polarizer in this case at the 45° position. Here, the P+LC regions and the LC region have a different color image than in FIG. 1b due to the changed position of the polarizer. This other color image is represented by thick dotted lines.

In FIG. 2a shows an embossing according to the invention on a specular silver print medium and a simplified representation of a color image that can be seen without the use of an aid. Here again it can be seen that without polarizing aid the color image for the area KL (isotropic clearcoat without embossing), P1/P2+LC (1/2 embossing with liquid crystal), P+KL (embossing with isotropic clearcoat) BP (liquid crystal without embossing) is identical everywhere.

In FIG. 2b shows an embossing 2a according to the invention on a silver print carrier with a specular sheen and a simplified example of a color image that can be seen with a linear polarizer in the 0° position. The KL and P+KL regions show no change in the color image, since only isotropic clearcoat was used here. On the contrary, the areas P1+LC and P2+LC now have two different color images, since the embossings in these areas differ in that they have a different orientation of the liquid crystals. The color image of the LC region may correspond to the image of the P1+LC region.

In FIG. 2c shows an embossing 2a according to the invention on a silver printing medium with a specular sheen and a simplified exemplification of a color image distinguishable by a linear polarizer in this case at the 45° position. Again different color images are observed in the liquid crystal coated areas P1+LC, P2+LC and LC. Here, due to the change in the position of the polarizer, the color image is inverted with respect to Fig. 2b.

CLAIM

1. Printing media containing at least one partial area with a transparent anisotropic layer, characterized in that the specified layer is applied by printing on the structure with layer orientation before and/or during the imprinting process of the specified layer, formed by tools for printing and/ or for embossing, said carrier contains at least one partial area with a colorless embossing and/or unembossed and/or embossed with a standard optical isotropic clear varnish, while all partial areas when viewed with the naked eye, regardless of the viewing angle, exhibit an optical image indivisible over partial regions.

2. Printing medium according to claim 1, characterized in that the anisotropic layer includes colorless birefringent nematic liquid crystals.

3. Printing medium according to claim 1, characterized in that it includes a partial area with a standard optical isotropic clear varnish.

4. Printing medium according to claim 1, characterized in that the partial area provided with an optical anisotropic varnish is made recognizable by an auxiliary optical means.

5. Printing medium according to claim 1, characterized in that at least one partial area with an optically anisotropic layer has predetermined areas delimited from each other with different layer orientation, as a result of which, in particular, when using an optical auxiliary means, certain separated areas with different color images.

6. A method of manufacturing a printing medium with an optically anisotropic layer applied to it at least on partial areas, characterized in that the anisotropic layer is applied by printing on at least one partial area of ​​the printing medium, which has at least one a layer-oriented structure formed by the printing and/or embossing tools before and/or during the imprinting process of said anisotropic layer, wherein at least one additional partial area is created in close proximity to this at least one partial area. an area with colorless embossing and/or embossing with an optical isotropic transparent varnish, while all partial areas when viewed with the naked eye, regardless of the viewing angle, exhibit an optical image indivisible over partial areas.

7. Method according to claim 6, characterized in that a force acts on the liquid crystals of the anisotropic liquid crystal layer in at least one direction through said structure, which leads, in particular before the anisotropic layer is cured, to align the liquid crystals, in particular along the correspondingly acting strength.

8. Method according to claim 6 or 7, characterized in that the area to be imprinted is provided with a mechanical structure and/or an electrostatic structure or potential relief, such structure providing one or more different orientations of the anisotropic layer.

9. Method according to claim 6, characterized in that the layer-oriented structure is created by a printing roller.

10. Method according to claim 6, characterized in that, after the imprinting process, the printing medium is rotated through an angle, followed by at least one more imprinting process.