JP2008200850A - Inkjet recording method for recording pattern layer and white solid coating layer - Google Patents

Abstract

An inkjet recording method capable of realizing remote proofing in package printing in a manner of printing a color image on a white background with high accuracy by an inexpensive inkjet method, and a printed matter obtained by the method.
An inkjet recording method is a method in which a non-white pattern layer P is provided on the surface of a transparent film substrate S, and then a white solid coating layer W is provided from above the non-white pattern layer P. The resolution of the non-white pattern layer P is higher than the resolution of the white solid coating layer W. The printed matter is obtained by the method described above.
[Selection] Figure 1

Description

  The present invention relates to an ink jet recording method for recording a pattern layer (in particular, a color pattern layer) and a white solid coating layer, and a printed matter obtained by the recording method. ADVANTAGE OF THE INVENTION According to this invention, the remote proofing in the package printing of the style which prints a color image on a white background can be implement | achieved with high precision by an inexpensive inkjet system.

In packaging of products such as confectionery, it is widely performed that a paper outer box for packaging is covered with a transparent film, and a part of or the whole of the transparent film is printed with a color image arranged on a white background. Alternatively, it is also widely performed to print a color image on a white background on the surface of a packaging plastic bag. For these printings, offset printing and flexographic printing are usually used.
In the printing industry, not only high quality but also cost reduction and delivery time reduction are strictly demanded, and the use of digital data is progressing from design confirmation to the start of printing on this machine. For example, the workflow for producing printed materials includes creation of input data, DDCP (Direct Digital Color
Proofing), press plate production using CTP (Computer To Plate), and printing on this machine proceed in this order, and digital data is often sent by e-mail even in DDCP proofing work to confirm the submitted data. Has been done.
In the DDCP calibration work, the proofreader who received the digital data by e-mail and the design orderer not only perform the calibration work and confirmation work on the computer screen, but also perform the calibration and confirmation by actually printing on the paper. There is. In this case, an ink jet method, a toner method, a thermal transfer method, a halftone dot method, or the like is used as the output method. However, in printing with a color image arranged on a white background, the cheapest ink jet method is not always satisfactory. There was a problem that the output quality could not be obtained.

  On the other hand, as white ink for inkjet recording, ink containing hollow polymer fine particles has been proposed (for example, Patent Document 1 or Patent Document 2). However, the use of these white inks containing hollow polymer fine particles for remote proofing by an ink jet method has never been proposed.

Japanese Patent No. 3562754 Japanese Patent No. 3639479

The inventor has intensively studied a method for obtaining a high-quality image by using an inkjet method as an output method when performing remote proofing of a printed matter (for example, offset printed matter) in which a color image is arranged on a white background. As a result, it has been found that the object can be achieved by making the resolution of the non-white pattern layer higher than that of the white solid coating layer.
The present invention is based on these findings.

  Therefore, the present invention is an ink jet recording method in which a non-white pattern layer is provided on the surface of a transparent film substrate, and then a white solid coating layer is provided on the non-white pattern layer. The present invention relates to the recording method, wherein the resolution is higher than the resolution of the white solid coating layer.

In a preferred embodiment of the method of the present invention, the non-white pattern layer is a color layer or a black to gray layer.
In another preferred embodiment of the method of the present invention, a white solid coating layer is provided so as to cover the entire non-white pattern layer provided on the surface of the transparent film substrate.
In still another preferred embodiment of the method of the present invention, the white ink composition for the white solid coating layer contains hollow polymer fine particles as a colorant.
In still another preferred embodiment of the method of the present invention, a transparent film substrate having an ink receiving layer is used.
The present invention also relates to a printed matter obtained by the recording method.

  According to the recording method of the present invention, it is possible not only to obtain a high-quality print in which a color image is reflected on a clean white background, but also to prevent a phenomenon in which the quality of the white ink overflows on the color image and the quality is deteriorated. In addition, for example, it is possible to provide a printed matter that sufficiently satisfies the print quality required for the DDCP calibration work.

  In the recording method of the present invention, for example, as shown in FIG. 1, a non-white pattern layer P and a white solid coating layer W are sequentially provided on a transparent film substrate S by an inkjet recording method to form a printed image. Then, as shown by an arrow A in FIG. 1, the printed image is observed from the non-printing surface side of the transparent film substrate S, and, for example, DDCP calibration work is performed.

  Examples of the transparent film substrate material that can be used in the method of the present invention include polyester films, polyolefin films, resin films such as polyvinyl chloride, paper such as plain paper, coated paper, and tracing paper, and resins. Examples thereof include coated paper and synthetic paper.

  The transparent film substrate preferably has an ink receiving layer on a surface on which a printed image is formed. As the ink receiving layer, a known ink receiving layer usually provided on a recording medium for an ink jet recording method is used as long as the ink receiving layer has a transparency that does not hinder the observation from the non-printing surface side of the transparent film substrate. be able to.

  As the known ink receiving layer, for example, an ink receiving layer made of a resin is known. Examples of the resin used for the ink receiving layer include, for example, Japanese Patent Application Laid-Open Nos. 57-38185 and 62-184879. Polyvinyl pyrrolidone or vinyl pyrrolidone-vinyl acetate copolymer as disclosed in JP-A Nos. 60-168651, 60-171143, and 61-134290. Resin composition mainly, copolymer of vinyl alcohol and olefin or styrene and maleic anhydride as disclosed in JP-A-60-234879, disclosed in JP-A-61-74879 A cross-linked product of polyethylene oxide and isocyanate, as described in JP-A-61-1181679 A mixture of carboxymethyl cellulose and polyethylene oxide as shown, a polymer obtained by grafting methacrylamide to polyvinyl alcohol as disclosed in JP-A-61-2132377, JP-A-62-220383 An acrylic polymer having a carboxyl group as disclosed, a polyvinyl acetal polymer as disclosed in JP-A-4-214382, etc., and JP-A-4-282282 and 4-285650. And various ink-absorbing polymers such as crosslinkable acrylic polymers.

Known ink receiving layers include those disclosed in JP-A-4-282282 and 4-285650.
In Japanese Patent Publication No. Gazette et al., An ink receiving layer using a polymer matrix composed of a crosslinkable polymer and an absorbent polymer is disclosed. Further, an ink receiving layer using alumina hydrate (cationic alumina hydrate) is also known, for example, JP-A-60-232990, JP-A-60-245588, and JP-B-3-24906. JP-A-6-199035 and JP-A-7-82694 disclose a recording medium in which fine pseudo boehmite type alumina hydrate is coated on a substrate surface together with a water-soluble binder. For example, Japanese Patent Application Laid-Open No. 10-203006 discloses an ink receiving layer using a synthetic silica mainly having a primary particle diameter of 3 nm to 30 nm by a vapor phase method. Furthermore, Japanese Patent Application Laid-Open No. 2001-328344 discloses an ink receiving layer containing an inorganic pigment and a polymer adhesive.
In the method of the present invention, a transparent film substrate provided with each ink receiving layer can be used.

  In the method of the present invention, any white ink composition that is usually used in the ink jet recording method can be used as the white ink composition for the white solid coating layer. Examples of such white pigments include inorganic white pigments, organic white pigments, and white hollow polymer fine particles. As the white ink composition, a water-based ink composition containing hollow polymer fine particles as a colorant component. Is preferably used.

  Examples of inorganic white pigments include alkaline earth metal sulfates such as barium sulfate, alkaline earth metal carbonates such as calcium carbonate, silicas such as finely divided silicic acid and synthetic silicates, calcium silicate, alumina, alumina Hydrates, titanium oxide, zinc oxide, talc, clay and the like can be mentioned. In particular, titanium oxide is known as a white pigment having preferable hiding properties, coloring properties, and dispersed particle sizes.

  Examples of the organic white pigment include organic compound salts disclosed in JP-A No. 11-129613 and alkylene bismelamine derivatives disclosed in JP-A Nos. 11-14365 and 2001-234093. Specific examples of the white pigment include Shigenox OWP, Shigenox OWPL, Shigenox FWP, Shigenox FWG, Shigenox UL, and Shigenox U (all of these are trade names manufactured by Hackol Chemical Co., Ltd.).

  The hollow polymer fine particles contained as the colorant component can be fine particles having an outer diameter of about 0.1 to 1 μm and an inner diameter of about 0.05 to 0.8 μm, and are insoluble in the solvent of the white ink composition. Thus, it is necessary that the component does not chemically react with other components, for example, a binder resin component.

  The hollow polymer fine particles are made of a synthetic polymer whose walls are permeable to liquid, and the space at the center of the hollow polymer fine particles can pass through the walls and allow liquid to enter and exit. Therefore, the space in the center of the hollow polymer fine particles is filled with the solvent in the state of the ink composition, and the specific gravity of the hollow polymer fine particles and the specific gravity of the ink composition are substantially the same. It is stably dispersed inside. On the other hand, when the ink composition is printed on the printing surface and dried, the space at the center of the hollow polymer fine particles is replaced with air, so that incident light is diffusely reflected between the resin and the space, and substantially white.

  Further, as described above, the hollow polymer fine particle contains a liquid in the fine particle before printing, but the liquid that has entered the fine particle passes through the fine particle wall after printing and diffuses. It can be of a type in which fine pores are filled with air or a completely sealed type in which air is initially contained inside.

Since it is desired that the hollow polymer fine particles used in the white ink composition do not precipitate in the ink composition, those having a specific gravity approximately equal to the specific gravity of the ink composition solution are preferable. For this reason, it is preferable to adjust the specific gravity of the ink composition solution using a specific gravity adjusting agent such as glycerol as necessary.

  Examples of commercially available hollow polymer fine particles satisfying the above properties include Ropaque OP-62 commercially available from Rohm and Haas. This is an aqueous dispersion containing 38% by weight of hollow polymer fine particles made of an acrylic / styrene copolymer. The inner diameter of the fine particles is about 0.3 μm, the outer diameter is about 0.5 μm, and the inside is filled with water.

  The hollow polymer fine particles can also be obtained by a known production method, for example, the method disclosed in US Pat. No. 4,089,800. The hollow polymer fine particles are substantially made of an organic polymer and exhibit mature plasticity. The thermoplastic resin used for the production of the hollow polymer fine particles is preferably a cellulose derivative, acrylic resin, polyolefin, polyamide, polycarbonate, polystyrene, styrene or other vinyl monomer copolymer, vinyl acetate, vinyl alcohol. And vinyl polymers such as vinyl chloride or vinyl butyral homopolymers or copolymers, diene homopolymers and copolymers, and the like. Particularly preferred thermoplastic polymers include copolymers of 2-hexyl acrylate, copolymers of methyl methacrylate, and copolymers of styrene and other vinyl monomers such as acrylonitrile. be able to.

  The content of the hollow polymer fine particles in the white ink composition used in the method of the present invention can be, for example, 0.1 to 20% by weight. When the content of the hollow polymer fine particles is 0.1% by weight or more, sufficient whiteness can be obtained. On the other hand, if it is 20% by weight or less, a sufficient amount of the ink binder resin component necessary for ensuring the viscosity required for the ink composition for ink jet printing can be contained, and as a result, sufficient printing adhesion can be achieved. Sex can be secured.

  In the present invention, the white pigment may be used alone or in combination. For the dispersion of the pigment, a ball mill, a sand mill, an attritor, a roll mill, an agitator, a Henschel mixer, a colloid mill, an ultrasonic homogenizer, a pearl mill, a wet jet mill, a paint shaker, or the like can be used. It is also possible to add a dispersant when dispersing the pigment.

  In addition to the white colorant component, the white ink composition used in the method of the present invention includes various components usually contained in an ink composition for inkjet printing, such as a resin component, a dispersant component, a solvent component (especially water), and the like. Can be contained. Moreover, as a white ink composition containing hollow polymer fine particles as a white colorant, for example, the composition described in Japanese Patent No. 3562754 (Patent Document 1) or Japanese Patent No. 3639479 (Patent Document 2) is used. You can also.

  The non-white ink composition for the non-white pattern layer used in the method of the present invention is, for example, a color ink composition, a black ink composition, or a gray ink composition. Examples of the color ink composition include a cyan ink composition, a magenta ink composition, a yellow ink composition, a light cyan ink composition, a light magenta ink composition, and a red ink composition and a green ink composition. Or a blue ink composition. As the non-white ink composition, the various ink compositions described above can be used alone or in combination of two or more.

  As the non-white ink composition, any non-white ink composition usually used in the ink jet recording method can be used, and a water-based ink composition containing a dye or a pigment as a colorant component is preferably used. In particular, it is preferable to use an ink composition that exhibits good characteristics (for example, color developability and fixability) with respect to the transparent film substrate or the ink receiving layer.

  In the method of the present invention, first, a non-white pattern layer is printed on one surface of a transparent film substrate, and then a white solid coating layer is provided on the non-white pattern layer. Here, the non-white pattern layer forms a pattern portion of the obtained printed image, and the white solid coating layer forms a white background (ground color portion), so as shown by an arrow A in FIG. When the printed image is observed from the non-printing surface side, an image having a non-white (color or black or gray) pattern can be observed on a white background (ground color portion).

  In the method of the present invention, both layers are printed so that the resolution of the non-white pattern layer is higher than the resolution of the white solid coating layer. In the printing (or printer) by the inkjet recording method, “resolution” means the number of dots per unit area (the number of ink droplets). In the case of color printing, it is necessary to represent intermediate colors with ink droplets (dots) of multiple types of colors, so the amount of ink per unit area (ink discharge amount) is lower for low resolution than for high resolution. ) Must be reduced. This is because it is necessary to consider the effect of bleeding. That is, in the case of low resolution, the size of one ink drop (dot) is larger than that in the case of high resolution, so that bleeding between adjacent ink drops (dots) is prevented. In addition, it is necessary to reduce the discharge amount. On the other hand, in the case of high resolution, the size of one ink drop (dot) is smaller than that in the case of low resolution, and the risk of bleeding between adjacent ink drops (dots) is reduced. Ink liquid can be ejected in a relatively large amount. Therefore, in the method of the present invention, when the resolution of the non-white pattern layer is set to be higher than the resolution of the white solid layer, the ink per unit area of the white solid layer printed after the non-white pattern layer is printed. Since the discharge amount is relatively small, even if there is a high density area in the non-white pattern layer, the total ink discharge amount per unit area does not overflow beyond the allowable amount of the transparent film substrate, and it is appropriate A level of printed matter can be obtained.

  The resolution of the white solid coating layer is preferably 180 to 1440 dpi, more preferably 360 to 720 dpi, and the resolution of the non-white pattern layer is preferably 600 to 9600 dpi.

  The method of the present invention can be suitably used when a printed material (for example, an offset printed material) in which a color image is arranged on a white background is remotely proofed and actually printed on a sheet for calibration and confirmation. In general, a printed matter in which a color image is arranged on a white background is provided on the surface of a transparent film substrate, and can be widely used in a printing method in which observation is performed from a non-printing surface.

  EXAMPLES Hereinafter, the present invention will be specifically described by way of examples, but these do not limit the scope of the present invention.

<Example 1>
Two inkjet printers [PX-A650; manufactured by Seiko Epson Corporation] were prepared. One of the printers used as a color output printer was loaded with a genuine ink cartridge. The other was a white output printer. That is, the black ink cartridge is filled with white ink, and the white ink cartridge is usually used in a portion where the black ink cartridge is installed. As the white ink, Japanese Patent No. 363947 is used.
The white ink described in Example 8 of No. 9 publication was used.
As the recording medium, a transparent film for inkjet [dedicated OHP sheet; manufactured by Seiko Epson Corporation] was used.

First, using a color output printer, a color image was output on the surface of the ink-jet transparent film on the ink receiving layer side and allowed to stand for several minutes to dry. The recording resolution at this time was 1440 × 720 dpi. Subsequently, a white solid coating layer having a size covering the color image portion was provided using a white output printer. The recording resolution of the white solid coating layer was 720 × 720 dpi.
When the obtained printed image was observed from the non-printed surface of the inkjet transparent film, the recorded image was obtained as a smooth recorded product without being affected by the printed surface. Further, there was no overflow or bleeding on the color image of white ink, and the printed matter was good.

  According to the method of the present invention, for example, remote proofing in package printing in which a color image is printed on a white background can be realized with high accuracy by an inexpensive inkjet method.

It is sectional drawing which shows typically the layered structure of the printed image formed on a transparent film base material by this invention method.

Explanation of symbols

S: Transparent film substrate; P: Non-white pattern layer; W: White solid coating layer.

Claims (6)

  An inkjet recording method in which a non-white pattern layer is provided on the surface of a transparent film substrate, and then a white solid coating layer is provided on the non-white pattern layer. The recording method, wherein the resolution is higher than the resolution of the coating layer.   The method according to claim 1, wherein the non-white pattern layer is a color layer or a black to gray layer.   The method of Claim 1 or 2 which provides a white solid coating layer so that the whole non-white pattern layer provided on the surface of the transparent film base material may be covered.   The method according to claim 1, wherein the white ink composition for the white solid coating layer contains hollow polymer fine particles as a colorant.   The method as described in any one of Claims 1-4 using the transparent film base material which has an ink receiving layer.   Printed matter obtained by the method according to claim 1.

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