JPH09175004A - Ink-jet recording material - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain an image that has a very little feathering even in the case of full-color or high-speed printing outputs, by providing a half-tone dot layer having no ink-absorptive property on an ink-receptive layer. SOLUTION: A carrier 1 can be a flexible material such as paper, plastic film, etc., and a plate material such as a glass or metal plate can be also used if it can be set on an ink-jet plotter. A half-tone dot layer 3 to be provided on an ink-receptive layer 2 has no ink-absorptive property but it merely means that the half-tone dot layer 3 is generally inferior to the ink-receptive layer 2 in inkabsorptive property. A resin to be used for the half-tone dot layer 3 can be styrene-maleic acid copolymer, vinyl chloride-vinyl acetate copolymer, acrylic resin, polyvinyl acetal, polyviunyl alcohol, etc. Thereby, ink is prevented from feathering on the half-tone dot layer 3 and the image resolving power can be improved.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ink jet recording material which eliminates "bleeding" of ink.

[0002]

2. Description of the Related Art Conventionally, an ink jet recording material has been used in which an ink receiving layer made of a water-soluble polymer or a water-absorbing polymer is provided on a support made of paper or a plastic film.

Various techniques have been applied to such an ink receiving layer so that the ink can be quickly absorbed and dried even if a large amount of ink is printed. Many of these technologies are related to improvement of resin formulation for forming the ink receiving layer, and such improvement of resin formulation is not applicable to full-color printing which requires absorption of a large amount of ink. .

However, even by improving the resin formulation as described above, full-color ink jet plotters have been developed in recent years.
It is difficult to cope with the increase in speed, and the problem of "bleeding" of ink is becoming very large. The ink jet recording method is a method of generating and flying a small droplet of ink and causing the small droplet of ink to be absorbed by the ink receiving layer. Therefore, when the small droplet of ink spreads in the surface direction of the ink receiving layer, the amount of spread Only that will reduce the resolution of the image. The spread of the ink in the surface direction becomes larger due to the second and subsequent inks adhering to the vicinity of the once absorbed ink. Therefore, in order to improve the resolution of the ink jet recorded image, it is necessary to eliminate such spreading of the ink in the surface direction, that is, "bleeding".

[0005]

SUMMARY OF THE INVENTION An object of the present invention is to provide an ink jet recording material capable of obtaining an image in which "bleeding" of ink is significantly reduced even when full color output and high speed output are performed. To do.

[0006]

The ink jet recording material of the present invention capable of achieving the above object has a structure in which a dot layer having no ink absorbability is provided on the ink receiving layer.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail.

As the ink receiving layer of the present invention, a conventionally known ink receiving layer can be used. Such an ink receiving layer is mainly composed of a hydrophilic polymer or a water-soluble polymer. Also, if necessary, mix water-resistant polymer such as water-resistant polymer and water-insoluble polymer, and extender pigments, ultraviolet absorbers, antioxidants, leveling agents and other additives to the extent that performance is not impaired. You can also use it.

Examples of the hydrophilic polymer or water-soluble polymer include polyvinyl alcohol, polyvinylpyrrolidone, water-soluble cellulose resin, water-soluble polyester resin, polyvinyl acetal, acrylic acid, acrylamide copolymer, melamine resin, polyether polyol and the like. Synthetic resins such as cross-linked products, gelatin, casein, starch,
Examples include natural resins such as chitin and chitosan.

Examples of the water-resistant polymer which has been made water resistant include those which are insolubilized by reacting with the water-soluble polymer through an ionic bond, a coordinate bond, a covalent bond, a hydrogen bond or the like.

As the water-insoluble polymer, styrene-maleic acid copolymer, vinyl chloride-vinyl acetate copolymer, acrylic resin, cellulose resin, polyester resin, (meth)
Examples thereof include acrylic acid ester and polyvinyl butyral.

Such an ink receiving layer can be constructed so that the layer itself functions as a support, and ink absorbing paper or cloth can be used as the construction, as shown in FIG. It may be laminated on the support 1.

Next, when a support is used, a flexible support such as paper or a plastic film is preferably used as the support 1. However, if it can be set in an ink jet plotter, a glass plate or metal. It may be a plate-shaped body such as a plate. Generally, the support is required to be transparent when it is used for the purpose of viewing the recorded image of the ink receiving layer through the support, which is generally called "back print". As the transparent support, polyester, polycarbonate, cellulose acetate, polyethylene,
A plastic film made of polystyrene or polypropylene, a glass plate or the like can be used.

On such a support 1, an ink receiving layer 2 is provided.
It is also possible to provide an anchor coat layer between the ink receiving layer and the ink receiving layer in order to control the adhesion with the ink receiving layer. Further, a back coat layer may be provided on the back surface of the support in order to prevent curling. Further, when a support is used, it is possible to provide an ink receiving layer on both sides of the support.

Next, a halftone dot layer 3 provided on the ink receiving layer 2
However, this halftone dot layer 3 does not have ink absorbability. Here, although it does not have ink absorbability, it does not mean that it cannot absorb ink at all, and it is generally inferior in ink absorbability as compared with the ink receiving layer 2. It is meant.

The halftone dot layer 3 is generally composed of a hydrophobic resin, but a water-soluble polymer or a water-absorbent polymer is used as long as it is inferior to the ink receiving layer 2 in water absorption. It is also possible.

Even if the halftone dot layer 3 has the same ink absorbency as the ink receiving layer 2 at the time of formation, only the halftone dot layer 3 has the ink absorbability due to light, heat, pressure, etc. during recording. It may be lowered. Examples of the resin used for the halftone dot layer 3 include thermoplastic, thermosetting, and photocurable resins such as styrene-maleic acid copolymer, vinyl chloride-vinyl acetate copolymer, acrylic resin, cellulose resin, and polyvinyl acetal. Compounds obtained by curing water-soluble resins such as polyvinyl alcohol and polyvinylpyrrolidone by known methods, water-soluble resins having cinnamoyl group, stilbazolium group, stilquinolium group, diazo group, etc., 1
Species or two or more can be used.

The halftone dot layer 3 can be formed as a halftone dot pattern of a photosensitive resin by printing a halftone dot pattern or a photographic method. The shape of the halftone dot is not particularly limited, and it may be a lattice shape as shown in FIG. 2A, a dot (circle) shape as shown in FIG. 2B, a dot (square) shape as shown in FIG.
Various shapes such as a stripe shape as shown in (d) can be adopted. The area ratio of halftone dots is not particularly limited, but the halftone dot area ratio [halftone dot forming portion / (halftone dot forming portion + halftone dot non-forming portion) × 100] is preferably in the range of 5% to 95%.
More preferably, 10% to 50% is adopted. The fineness of the halftone dots cannot be generally stated depending on the resolution of the image to be obtained, but finer ones are preferable from the viewpoint of image resolution, and actually 65 to 250 lines per inch are good. is there. The thickness of the halftone dot layer is preferably 0.5 μm or more in order to suppress “bleeding” of the image, and is preferably 100 μm or less in order to reduce the manufacturing cost.

Further, by forming a halftone dot with a highly transparent resin, it can be used as an OHP (overhead projector) application, and as described above by forming a halftone dot colored with an extender pigment or the like. It can also be used as a back print. Further, it is possible to easily manufacture a recording material having a metallic luster on the background such as a metal powder or a recording material whose background is colored by adding a colored dye or pigment without changing the ink receiving layer itself. You can

Since the ink jet recording material of the present invention does not absorb the ink in the dot forming portion by providing the above dot layer, the ink is absorbed only in the dot not forming portion, and the dot is not formed. Since "bleeding" of the ink to the formed portion can be prevented, the resolution of the image is improved.

[0021]

EXAMPLES The present invention will be described below based on examples.
In the present invention, unless otherwise indicated, “%”, “part”
Are all by weight.

[Example 1] The following coating liquid for the ink receiving layer was applied to one surface of a polyester film having a thickness of 75 µm by a bar coater method so that the film thickness after drying was 8 µm, and the coating was performed at 110 ° C for 2 minutes. It was dried under the conditions of No. 1 to provide an ink receiving layer.

(Coating liquid for ink receiving layer) -Polyvinyl alcohol (saponification degree 71-75%) 6 parts (Gothenol KP-06: Nippon Synthetic Chemical Industry Co., Ltd.)-Polyvinyl alcohol (saponification degree 98-99%) 4 parts (Gothenol NH-18: Nippon Synthetic Chemical Industry Co., Ltd.) ・ Water 90 parts ・ Silica 10 parts (Sylysia 435: Fuji Silysia Chemical Co., Ltd.)

Next, a hydrophobic ink (offset ink F gloss medium: Dainippon Ink and Chemicals, Inc.) was applied on the ink receiving layer using an offset printing machine in the form of halftone dots (area ratio: 50%, number of lines: 175 lines). , Shape: dots (circles) were printed and dried to have a thickness of about 1 μm, and an inkjet recording material having a halftone dot layer formed was produced.

This ink jet recording material was used as MJ800.
When fine lines were printed with C (Seiko Epson Corporation) and the presence or absence of "bleeding" was confirmed by visual evaluation, the fine lines were reproduced very cleanly, and "bleeding" was almost absent.

[Example 2] The following coating liquid for ink receiving layer was applied to one surface of a polyester film having a thickness of 75 µm by a bar coater method so that the film thickness after drying was 5 µm, and the coating was performed at 80 ° C for 5 minutes. It was dried under the conditions of No. 1 to provide an ink receiving layer.

(Coating liquid for ink receiving layer) -Polyvinyl acetal (solid content 8%) 95 parts (ESREC KX-1: Sekisui Chemical Co., Ltd.)-Silica 5 parts (Sylysia 435: Fuji Silysia Chemical Co., Ltd.)

Next, a photosensitive resin (SP
P-LS400: Toyo Gosei Co., Ltd.) has a film thickness of 1 after drying.
Coating by the bar coater method so as to be 0 μm, 110
It was dried under the condition of 2 ° C. for 2 minutes. After that, the halftone dot original (area ratio: 50%, number of lines: 175 lines, shape: dot (circle)) is sufficiently exposed to the halftone dot forming photosensitive layer by an ultraviolet irradiation device, and the non-exposed area of the halftone dot layer is developed It was washed off with a liquid to prepare an ink jet recording material with halftone dots formed.

This ink jet recording material was used as MJ800.
When fine lines were printed with C (Seiko Epson Corporation) and the presence or absence of "bleeding" was confirmed by visual evaluation, the fine lines were reproduced very cleanly, and "bleeding" was almost absent.

Comparative Example 1 An ink jet recording material was prepared by providing the ink receiving layer used in Example 1 on one surface of a polyester film having a thickness of 75 μm in the same manner as in Example 1.

When this ink jet recording material was evaluated for "bleeding" in the same manner as in Example 1, the thin line was thicker due to "bleeding" as a whole.

[Comparative Example 2] An ink jet recording material was prepared by forming the ink receiving layer used in Example 2 on one side of a 75 μm thick polyester film in the same manner as in Example 2.

When this ink jet recording material was evaluated for "bleeding" in the same manner as in Example 2, the thin line was thicker due to "bleeding" as a whole.

Comparative Example 3 The hydrophobic ink used in Example 1 was uniformly applied on one side of a 75 μm thick polyester film on the ink receiving layer used in Example 1 to a thickness of about 1 μm. The ink-jet recording material was provided as above.

When this ink jet recording material was evaluated for "bleeding" in the same manner as in Example 1, the ink jet ink was not absorbed at all and did not dry.

[0036]

According to the ink jet recording material of the present invention, it is possible to obtain an image in which "bleeding" of ink is extremely reduced even when full color output and high speed output are performed.

[Brief description of the drawings]

FIG. 1 is a sectional view showing an embodiment of an inkjet recording material of the present invention.

FIG. 2 is a schematic diagram showing a shape of a halftone dot of the present invention.

[Explanation of symbols]

 1 ... Support 2 ... Ink receiving layer 3 ... Halftone dot layer

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Junichi Noda 4-63 Suzuya, Yono City, Saitama Prefecture Kimoto R & D Laboratories

Claims (1)

[Claims] 1. An ink jet recording material comprising a halftone dot layer having no ink absorbability provided on an ink receiving layer.