JPH08258409A - Ink-jet recording material - Google Patents

Abstract

PURPOSE: To provide an ink-jet recording material which has enough ink absorption to cope with full color recording and is free from curling, sticking, and blocking on the surface. CONSTITUTION: In an ink-jet recording material, a porous layer of a non- hydrophilic resin is formed as an ink receiving layer at least on one paper surface of a support in which paper is laminated at least on one side of a plastic film.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to an ink jet recording material.

[0002]

2. Description of the Related Art Generally, an ink used for ink jet recording is an aqueous ink containing water as a main component and a small amount of alcohol or the like added thereto from the viewpoint of safety and recording characteristics. Under these circumstances, recording materials conventionally used for ink jet recording have a paper or plastic film surface provided with an ink receiving layer made of a porous or hydrophilic resin such as polyvinylpyrrolidone, polyvinyl alcohol or gelatin. Has been used.

However, in the state of the coating liquid, these do not contain an organic solvent and therefore have little effect on the human body, which is preferable for safety and hygiene, but bubbles are generated in the coating liquid as compared with the case where an organic solvent is used. The workability during manufacturing was extremely poor, such as easy handling, poor leveling, and time required for drying. Further, since the hydrophilic resin is inferior in water resistance due to its property, there is a drawback that stickiness or blocking occurs on the surface of the ink receiving layer with time after forming the coating film.

On the other hand, in recent years, due to remarkable progress in ink jet recording apparatuses, full-color images can be obtained relatively easily. Generally, in full-color printing, the amount of ink absorbed per unit area is larger than that in monochrome printing. Therefore, problems such as a longer ink drying and fixing time and the inability to absorb the ink may occur. Therefore, it is conceivable to increase the thickness of the ink receiving layer in order to improve the ink absorbability.

However, in general, when ink adheres to the surface of the ink receiving layer, or when the recording material is placed in a place with high humidity or in a dry place, the receiving portion is likely to expand or contract to cause curling. The thicker the ink receiving layer, the worse the situation tends to be. For this reason,
Even when the ink receiving layer is formed thin, there is a demand for an ink receiving layer which has good ink absorbency and can obtain a high-definition recorded image, and which is not easily affected by humidity and curling.

As an ink jet recording material satisfying such performances, one using a porous or brushing layer in the ink receiving layer (Japanese Patent Laid-Open No. 58-136478).
JP-A-60-122188) has been proposed, but satisfactory printing performance has not been obtained.

[0007]

SUMMARY OF THE INVENTION It is an object of the present invention to provide an ink jet recording material which has ink absorbability sufficient for full color recording, does not cause curling, and does not cause surface stickiness or blocking. And

[0008]

The ink jet recording material of the present invention which achieves the above-mentioned object is composed of a non-hydrophilic resin on at least one paper surface of a support in which paper is bonded to at least one surface of a plastic film. A porous ink receiving layer is provided.

The present invention will be described in detail below.

As the support of the present invention, a support obtained by laminating paper on one side or both sides of a plastic film is used.

Examples of the plastic film include films made of polyester, polycarbonate, cellulose acetate, polyimide, polyethylene, polystyrene, polypropylene, polyvinyl chloride, polyvinyl alcohol and the like.

As the paper to be attached to one side or both sides of the plastic film, either Japanese paper or Western paper can be used. The raw materials for Japanese paper are swordfish, hemp, Japanese camellia, and geese.
Moreover, wood pulp, synthetic pulp, etc. can be used as a raw material of the foreign paper, and the thickness is 6 to 29 g / m ² , preferably 9 to 15
Those of g / m ² are suitable for the present invention.

When Japanese paper or foreign paper is attached to a plastic film, an adhesive is usually used. Examples of the adhesive used include urea-based, phenol-based, resorcinol-based, epoxy-based, urethane-based, polyester-based,
Examples of the adhesive include isocyanate-based, vinyl acetate-based, acrylic-based, cyanoacrylate-based, copolymer nylon-based, and modified rubber-based adhesives.

By using such a support, it is possible to suppress the bulging and curling of the image area due to printing, and to provide the surface with blocking resistance and sufficient ink absorption while maintaining the strength of the coating film. .

The ink receiving layer is porous and made of a non-hydrophilic resin.

The non-hydrophilic resin is not particularly limited as long as it forms a porosity, but is not limited to acrylic type, vinyl chloride type, vinyl acetate type, cellulose type, phenol type, polyester type, urethane type, phenol type, Nylon,
It is preferable to use a modified rubber resin or the like, or a copolymer or modified product thereof alone or in combination.

By using these non-hydrophilic resins, it is possible to obtain an ink jet recording material having high water resistance, which is less susceptible to humidity, less likely to curl due to the characteristics of the support, and less sticky or blocking on the surface. .

The porous layer has open pores on the surface of the membrane, and continuous cells or partial continuous cells are formed in the thickness direction of the membrane. Fine pores having a diameter of about 5 μm or less, so-called fine pores. Is a layer having. The microporous layer can be formed by dissolving in a solvent in which a solvent (good solvent) that dissolves the above-mentioned resin well and a solvent (poor solvent) that hardly dissolves the resin are mixed, and applied and dried on a support. The diameter of the pores can be adjusted by changing the mixing ratio of the good solvent and the poor solvent.

Further, the porous layer may be a layer having coarse open pores having a diameter of 5 μm or more, that is, a so-called brushing layer. The brushing layer can be formed by applying the resin solution and then drying it in a humidity atmosphere of about 60 to 80%, and usually, the bubbles are about 5 continuous cells from the surface layer.

The thickness of the porous layer is not particularly limited,
1 to 20 from the viewpoint of ink absorbency and coating suitability for coating
The range of μm is preferred. When the thickness is 1 μm or more, the ink absorptivity can be improved, and when the thickness is 20 μm or less, the absorption of the ink by the fibrous material of the support is not obstructed and the image can be fixed quickly.

By forming these fine pores in the above-mentioned support, the performance of the ink receiving layer is maintained while maintaining the characteristic of the support itself that is excellent in dimensional stability and is durable.
Further, since the fibrous material of the paper of the support assists the ink absorption which cannot be covered by the fine pores, the ink absorption is remarkably improved as compared with the case where the plastic film is used as the support.

In addition to the above-mentioned substances, the ink receiving layer may be added with an antioxidant, an ultraviolet absorber, a surfactant, a pH adjusting agent or the like to the extent that the above-mentioned performance of the ink receiving layer is not impaired. good.

Further, in order to enhance the ink absorption performance, a hydrophilic resin such as gelatin, starch, protein, casein, chitin, chitosan, or another natural polymer resin, polyvinyl alcohol, is provided between the support and the ink receiving layer. By providing a hydrophilic resin layer consisting of a copolymer or a modified product of a synthetic polymer resin such as polyvinylpyrrolidone, water-soluble cellulose, urethane, polyester, acrylic acid, etc., alone or in combination, The absorption performance can be improved. However, in this case, it is necessary not to dissolve the lower layer when forming the upper layer. Therefore, it is necessary that the resin forming the porous layer and the resin forming the lower layer are incompatible with each other, or that the solvent of the porous layer does not dissolve the resin of the lower layer.

For example, when a water-soluble and non-oil-soluble resin such as polyvinyl alcohol, gelatin or hydroxycellulose is used for the lower layer, all the resins mentioned above can be used as the resin constituting the porous layer.

Further, when the paper is attached to only one surface of the plastic film, or when the ink receiving layer is provided on only one surface of the support, the ink of the support is formed on the surface opposite to the paper of the plastic film. It is effective to provide a back coat layer on the side opposite to the receiving layer for reducing the degree of curling, improving the slipperiness and the transportability.

[0026]

In the ink jet recording material of the present invention, a paper having a plastic film laminated on at least one side is used as a support, and a non-hydrophilic resin is used on the paper layer to provide an ink receiving layer having a porous structure. Curling does not occur, the influence of humidity and water content of ink does not occur, and stickiness and blocking of the surface do not occur, and the ink absorbability can be greatly enhanced.

[0027]

【Example】

(Example 1) An acrylic resin emulsion type adhesive was applied to both sides of a transparent polyester film having a thickness of 25 μm by a roll coater so as to be 3 g / m ^2, and after drying, 13 g / m ² of Japanese paper was applied to both sides. A substrate was prepared by laminating the substrates. A coating liquid prepared by dissolving 10 parts by weight of a vinyl chloride / vinyl acetate resin (400 × 150S: manufactured by Nippon Zeon Co., Ltd.) as a coating liquid for the ink receiving layer in 65 parts by weight of methyl ethyl ketone and 35 parts by weight of n-butanol on one surface of this support. Was coated with a bar coater to a thickness of 5 μm and dried at 80 ° C. for 5 minutes with a drier to obtain an ink jet recording material having an average of 0.8 μm open pores.

(Example 2) On one side of the support of Example 1, 10 parts by weight of polyvinyl alcohol resin (Gohsenol KH-17: manufactured by Nippon Synthetic Chemical Industry Co., Ltd.) as a lower layer coating solution was dissolved in 90 parts by weight of pure water. The working solution was applied by a bar coater to a thickness of 5 μm and dried at 100 ° C. for 5 minutes by a dryer, and then the ink receiving layer coating solution of Example 1 was further applied by a bar coater. By drying at 5 ° C. for 5 minutes, an inkjet recording material having a film thickness of 3 μm and having open pores of 0.8 μm on average was obtained.

Comparative Example 1 On one side of the support of Example 1, 10 parts by weight of vinyl chloride / vinyl acetate resin (400 × 150S: manufactured by Zeon Corporation) was dissolved in 100 parts by weight of methyl ethyl ketone as a coating liquid for the ink receiving layer. The coating liquid was applied with a bar coater to a thickness of 5 μm and dried at 80 ° C. for 5 minutes with a drier to obtain an inkjet recording material having no open pores.

Comparative Example 2 Instead of the ink receiving layer of Example 1, polyvinyl alcohol (Gosenol KH-1) was used.
7: manufactured by Nippon Synthetic Chemical Industry Co., Ltd.) was dissolved in water to prepare a 10% solution, which was applied to a thickness of 5 μm with a bar coater and dried to obtain an inkjet recording material.

(Comparative Example 3) A support having a thickness of 25 μm
Using the transparent polyester film of No. 3, an ink receiving layer having the same composition as in Example 1 was formed.

An ink jet printer (BJC600J: manufactured by Canon Inc.) is attached to the obtained ink jet recording material.
Table 1 shows the results of evaluation of ink drying property, bleeding property, water resistance and blocking by printing with.

[0033]

[Table 1]

(Drying property) Solid printing was performed on the entire surface, and after a lapse of a certain time after printing, the printed portion was rubbed with a finger, "No" was found when the ink was not rubbed, and a small amount was generated but no problem in use. "△". Those that occurred considerably and had problems in use were marked with "x".

(Bleed) Fine lines were printed, and the thin lines were visually evaluated, and those with no bleed were marked with "O" and those with bleed were marked with "X".

(Water resistance) Solid printing was performed on the entire surface, and after drying, it was soaked in water and rubbed with a nylon scrubbing to visually evaluate the strength of the coating film. When peeling did not occur, "○" was given, and when peeling occurred. Was designated as "x".

(Blocking) Recording material at 40 ° C./90
After leaving it in the atmosphere of% Rh for 24 hours,
The sheets were overlapped with each other and subjected to a constant load, and after a lapse of a predetermined time, they were peeled off, and the presence or absence of blocking was visually evaluated. Those in which blocking did not occur were marked with "O", and those with severe blocking were marked with "X".

The recording materials of Examples 1 and 2 were excellent in all evaluations of dryness, bleeding, water resistance and blocking. Particularly in Example 2, the ink absorption performance was very excellent.

The recording material of Comparative Example 1 did not have open pores, and therefore was extremely inferior in drying property and bleeding property as compared with Examples.

Since the recording material of Comparative Example 2 used a hydrophilic resin, it was inferior in drying property, water resistance and blocking property as compared with Example.

The recording material of Comparative Example 3 was inferior in ink absorbability as compared with Examples, since the support was only a plastic film.

[0042]

INDUSTRIAL APPLICABILITY The ink jet recording material of the present invention has ink absorbability sufficient for full color recording,
It does not cause curling, does not cause surface stickiness or blocking, and has excellent coating workability.

Further, by using a plastic film on which paper is laminated on at least one side as the support and providing the ink receiving layer on the paper, it is possible to enhance the ink absorbability at the same time, and also toughness and dimensional stability. I was able to improve.

 ─────────────────────────────────────────────────── ─── Continuation of front page (72) Inventor Koji Matsuyama 4-63 Suzuya, Yono-shi, Saitama Inside Kimoto Central Research Institute (72) Inventor Toshio Yamagata 4-63 Suzuya, Yono-shi, Saitama Stock company Kimoto Central Research Institute

Claims (2)

[Claims] 1. A support having at least one surface of a plastic film laminated with paper, on at least one paper surface of the support,
An ink jet recording material, wherein a porous layer made of a non-hydrophilic resin is formed as an ink receiving layer. 2. The ink jet recording material according to claim 1, wherein a hydrophilic resin layer is provided between the support and the ink receiving layer.