JP2001260523A - Ink jet recording sheet for pigment ink - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain an ink jet recording sheet having fixability of a water base pigment ink and excellent gloss. SOLUTION: The ink jet recording sheet comprises an ink acceptive layer and a gloss developing layer provided on a support. Thus, the sheet is obtained by press bonding the developing layer to a mirror surface roll and drying the layer while the developing layer remains a wetting state. A pigment and an adhesive are contained in the support. In this case, as the adhesive of the acceptive layer, an aqueous polyurethane resin having a glass transition temperature (Tg) of 20 deg.C or higher is used.

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 sheet for a pigment ink used in an ink jet recording system for recording using a pigment ink in which a colored pigment is dispersed, and more particularly, to a color printing section after printing. The present invention relates to an ink jet recording sheet having excellent pigment fixability and water resistance and excellent gloss.

[0002]

2. Description of the Related Art Ink-jet recording is a method for recording images, characters, and the like by jetting fine droplets of ink onto various recording sheets, such as paper and film, based on various operating principles. It has features such as noise, easy multi-coloring, great flexibility in recording patterns, and no need for development-fixing. It is rapidly spreading in various applications as a recording device for various figures and color images, including kanji. . Further, in order to improve water resistance and light resistance, an ink jet recording method using a pigment ink in which a colored pigment is dispersed has been newly proposed and put to practical use.

In recent years, with the expansion of applications such as high-speed ink jet recording, high definition of recorded images, and full color printing, ink jet recording sheets having high surface gloss and excellent appearance have been demanded. Generally, as a paper with a high surface gloss, a plate-like white pigment is coated on the surface,
A so-called cast coating obtained by copying the mirror surface by applying a calender-treated coated paper or a wet coating layer to a heated drum surface having a mirror surface as required, and drying it. Paper and the like are known. This cast coated paper has higher surface gloss and better surface smoothness than super-calendered normal coated paper, and provides excellent printing effect. It is exclusively used for For example, JP-A-11-180036 discloses an inkjet recording sheet containing an aqueous polyurethane resin in a cast layer. However, when the cast layer contains an aqueous polyurethane resin, there is a disadvantage that the absorbability of the pigment ink is reduced.

[0004] As an ink used in the ink jet recording system, an aqueous dye ink (hereinafter referred to as a dye ink) has been frequently used, and has been dominant. However, as outdoor uses such as posters increase, this kind of ink has a problem that the recorded image is inferior in water fastness and light fastness because the colorant is a water-soluble dye. In recent years, an ink in which a colored pigment as a coloring component is dispersed for the purpose of improving this drawback (hereinafter, referred to as a pigment ink)
Attempts have been made to apply this method to an ink jet recording system, as disclosed in JP-A-56-147868 and JP-A-56-1.
No. 47871, JP-A-2-255875, JP-A-3-76767, JP-A-3-76768, and the like have been proposed.

[0005] However, a cast coating ink jet recording sheet having a high gloss tends to leave the colored pigment in the pigment ink on the surface of the coating layer. If applied to
The solvent component etc. in the ink is absorbed in the sheet or evaporates from the sheet surface, but the colored pigment itself in the ink remains on the sheet surface forever, and so-called `` scratching '' such as touching by hand occurs on the sheet surface. When this occurs, a phenomenon occurs in which the colored pigment as a coloring component is peeled off, and in some cases, an image is lost.

[0006]

SUMMARY OF THE INVENTION An object of the present invention is to provide a glossy recording sheet which is excellent in fixability of a pigment ink such as resistance to abrasion of an ink jet recorded image using the pigment ink. It is in.

[0007]

An object of the present invention is to provide an ink-receiving layer and a gloss-generating layer which are successively laminated on a support, and while the gloss-generating layer is in a wet state, pressed against a mirror-finished roll and dried. In an ink jet recording sheet having a mirror gloss finish, the ink receiving layer has a glass transition temperature (Tg) of 20.
The problem could be solved by containing an aqueous polyurethane resin having a temperature of at least ° C.

In order to obtain better pigment ink fixability and higher surface gloss, the glass transition temperature of the aqueous polyurethane resin is preferably in the range of 30 ° C. or more and 80 ° C. or less.

It is more preferable that the 75-degree specular glossiness according to JIS P-8142 on the gloss-developing layer side be 60% or more, since glossiness comparable to that of a photograph can be obtained.

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the ink jet recording sheet of the present invention will be described in detail.

The support according to the present invention is LBKP, NB
Chemical pulp such as KP, GP, PGW, RMP, TM
Mechanical pulp such as P, CTMP, CMP, CGP, DI
Wood pulp such as waste paper pulp such as P, or kenaf,
Various additives such as conventionally known white pigments, binders, sizing agents, fixing agents, retention agents, cationizing agents, paper strength agents, toning dyes, etc. are mainly composed of non-wood pulp such as bagasse and cotton. A base paper manufactured by mixing one or more kinds and using various apparatuses such as a fourdrinier paper machine, a round paper machine, a twin wire paper machine, and an art paper or a coat having a coat layer provided on the base paper. Coated paper such as paper and cast-coated paper can also be used. Such a base paper and a coated paper may be provided with an ink receiving layer as it is, or a calendar device such as a machine calendar, a TG calendar, or a soft calendar may be used to control flattening.

The ink receiving layer according to the present invention contains an aqueous polyurethane resin having a glass transition temperature of 20 ° C. or higher.
The aqueous polyurethane resin is also commonly referred to as urethane emulsion, urethane latex, or polyurethane latex. A polyurethane resin is obtained from a reaction between a polyisocyanate compound and an active hydrogen-containing compound, and is defined as a polymer compound containing a relatively large number of urethane bonds and urea bonds.

The polyisocyanate compound for producing an aqueous polyurethane resin is not particularly limited. For example, aromatic polyisocyanates such as tolylene diisocyanate and 4,4'-diphenylmethane diisocyanate;
In addition, aliphatic and alicyclic polyisocyanates such as hexamethylene diisocyanate and isophorone diisocyanate are used.

As the active hydrogen-containing compound for producing an aqueous polyurethane resin, a compound having a hydroxyl group or an amino group is generally used. As the compound having a polymer, polyester diol, polyether diol, and polycarbonate diol are exemplified. As those having a molecular weight, ethylene glycol, 1,4-butanediol,
And glycols such as 1,6-hexanediol, and diamines such as isopropyldiamine and hexamethylenediamine.

The aqueous polyurethane resin is dispersed or emulsified in the form of fine particles in an aqueous medium, and the dispersed particles have a particle size of about 0.001 to 10 μm. And a milky white emulsion. In the present invention, these are collectively referred to as an aqueous polyurethane resin. Aqueous polyurethane resin is a forced emulsification type in which forced mechanical emulsification is performed with high mechanical shear force in the presence of an emulsifier, and a hydrophilic group such as an ionic group is introduced into the molecular chain to impart hydrophilicity without the aid of the emulsifier. And a self-emulsifying type which can be stably dispersed in water, and a dissolving type which is further dissolved in water. Among them, the self-emulsifying aqueous polyurethane resin is excellent in gloss, water resistance and the like, and is preferably used in the present invention. Depending on the type of hydrophilic group to be introduced, self-emulsifying aqueous polyurethane resins may be of a cationic type (introducing an amino group or the like), an anionic type (introducing a carboxyl group or a sulfone group), or a nonionic type (a polyethylene glycol group). Etc.). Among them, a cationic aqueous polyurethane resin (cationic aqueous polyurethane resin) in which a cationic group such as a tertiary amino group is introduced and neutralized or quaternized with an acid.
Is preferred. When the aqueous polyurethane resin is cationic, as described below, a cationic compound as an aqueous ink fixing agent may be blended in the ink receiving layer,
Excellent miscibility.

Among the aqueous polyurethane resins, those having a glass transition temperature of 20 ° C. or higher can be used. More preferably, the glass transition temperature is from 30 ° C to 80 ° C.
When the glass transition temperature is lower than 20 ° C., the absorbability of the ink receiving layer deteriorates. Further, when the glass transition temperature of the aqueous polyurethane resin exceeds 80 ° C., there is a tendency that the 75 ° specular gloss is reduced, and the adhesive strength of the ink receiving layer is reduced,
The adhesive strength with the glossy layer is not sufficiently exhibited. In addition, the glass transition temperature referred to in the present invention is based on a method specified in JIS K7121.

The ink receiving layer according to the present invention may contain an ink-absorbing pigment and an adhesive in addition to the above-mentioned aqueous polyurethane resin.

As the pigment, one or more known pigments can be used. For example, light calcium carbonate, heavy calcium carbonate, kaolin, talc, calcium sulfate, barium sulfate, titanium dioxide, zinc oxide, zinc sulfide, zinc carbonate, satin white, aluminum silicate, diatomaceous earth, calcium silicate, magnesium silicate, synthetic non-crystalline Inorganic pigments such as crystalline silica, colloidal silica, colloidal alumina, pseudoboehmite, aluminum hydroxide, alumina, lithopone, zeolite, hydrohaloysite, magnesium carbonate, magnesium hydroxide, styrene plastic pigment, acrylic plastic pigment, polyethylene, micro Organic pigments such as capsules, urea resins, and melamine resins can be used. Among the above-mentioned pigments, porous inorganic pigments are preferable, and examples thereof include porous amorphous synthetic silica, porous magnesium carbonate, and porous alumina. Particularly, porous synthetic amorphous silica having a large pore volume is preferable.

Examples of the adhesive include starch derivatives such as oxidized starch, etherified starch, and phosphated starch;
Cellulose derivatives such as carboxymethylcellulose and hydroxyethylcellulose; polyvinyl alcohol derivatives such as casein, gelatin, soybean protein, polyvinyl alcohol, or silyl-modified polyvinyl alcohol;
Conjugated diene-based copolymer latex such as polyvinylpyrrolidone, maleic anhydride resin, styrene-butadiene copolymer, methyl methacrylate-butadiene copolymer;
Acrylic copolymer latex such as polymer or copolymer of acrylic acid ester and methacrylic acid ester; vinyl copolymer latex such as ethylene vinyl acetate copolymer; or carboxy group of these various copolymers Functional group-modified copolymer latex with functional group-containing monomer; water-based adhesive such as thermosetting synthetic resin such as melamine resin and urea resin; polymer or copolymer of acrylic acid ester and methacrylic acid ester such as polymethyl methacrylate Coalescing resin latex; polyurethane resin,
Examples include unsaturated polyester resin, vinyl chloride-vinyl acetate copolymer, polyvinyl butyral, and alkyd resin latex. Among these aqueous polymer binders, polyvinyl alcohol or polyvinyl alcohol derivatives such as silyl-modified polyvinyl alcohol are preferred from the viewpoint of adhesive strength.

Further, when applied to an ink jet recording system using a dye ink in combination, it is preferable to contain a cationic compound in addition to the above. The cationic compound is a secondary amine, a tertiary amine or a quaternary amine which forms an insoluble salt with a sulfonic acid group, a carboxyl group, an amine group or the like in a water-soluble direct dye or a water-soluble acid dye contained in an aqueous dye ink. It is a compound containing a quaternary ammonium salt. The cationic compounds may be used alone or in combination of two or more.

In addition, additives such as a dye fixing agent, a pigment dispersant, a thickener, a flow improver, a surfactant,
Antifoaming agent, foam inhibitor, release agent, foaming agent, penetrant, coloring dye,
A coloring pigment, a fluorescent whitening agent, an ultraviolet absorber, an antioxidant, an antiseptic, an antibacterial agent, a waterproofing agent, a wet paper strength enhancer, a dry paper strength enhancer, and the like can also be appropriately compounded.

In the present invention, apparatuses for coating or impregnating a coating composition for forming an ink receiving layer include various blade coaters, roll coaters, air knife coaters, bar coaters, rod blade coaters, curtain coaters, short dwell coaters, and the like. Various devices such as a size press and a spray can be used on-machine or off-machine.

In the present invention, the total number and structure of the ink receiving layers provided on the support are not particularly limited. That is, two or more ink receiving layers can be provided on one side of the support, or one or more ink receiving layers can be provided on both sides. In the present invention, it is also possible to provide a coating layer on the surface opposite to the surface on the support on which the ink receiving layer is provided, for the purpose of curl correction or improvement in transport suitability.

In the present invention, the gloss receiving layer is provided on the ink receiving layer. As for the glossy layer, those containing a pigment and a binder as main components are preferably used. In addition, various additives can be appropriately compounded. As the pigment, one or more known pigments can be used. For example, light calcium carbonate, heavy calcium carbonate, magnesium carbonate, kaolin, talc, calcium sulfate, barium sulfate, titanium dioxide, zinc oxide, zinc sulfide, zinc carbonate, satin white, aluminum silicate, diatomaceous earth, calcium silicate, magnesium silicate , Synthetic amorphous silica, colloidal silica, alumina, colloidal alumina, pseudoboehmite, aluminum hydroxide, lithopone, zeolite, hydrohaloisite, inorganic pigments such as magnesium hydroxide, styrene-based plastic pigments,
Organic pigments such as acrylic plastic pigments, polyethylene, microcapsules, urea resins, melamine resins, and the like. Among these, good gloss can be obtained by using colloidal particles having a dispersed particle diameter of 500 nm or less, such as colloidal silica, colloidal alumina, and pseudoboehmite.

Examples of the binder include starch derivatives such as oxidized starch, etherified starch and phosphated starch, cellulose derivatives such as carboxymethylcellulose and hydroxyethylcellulose, casein, gelatin, soy protein,
Polyvinyl alcohol or a derivative thereof, polyvinylpyrrolidone, maleic anhydride resin, styrene-butadiene copolymer, conjugated diene-based copolymer latex such as methyl methacrylate-butadiene copolymer, or a polymer or copolymer of acrylate and methacrylate. Acrylic polymer latex such as acrylic polymer such as polymer, vinyl polymer latex such as ethylene-vinyl acetate copolymer, or functional group based on functional group-containing monomer such as carboxy group of these various polymers Aqueous adhesives such as modified polymer latex, thermosetting synthetic resin such as melamine resin, urea resin, etc., acrylate or methacrylate polymer or copolymer resin such as polymethyl methacrylate, polyurethane resin, unsaturated polyester resin , Vinyl chloride-vinyl acetate cupo Mer, polyvinyl butyral, may be mentioned synthetic resin adhesive such as alkyd resins. The amount of the binder is 100
3 to 70 parts by weight, preferably 5 to 5 parts by weight,
When the amount is less than 3 parts by weight, the coating strength of the gloss-developing layer is insufficient, and when it exceeds 70 parts by weight, the ink absorbency decreases.

Further, as additives, dye fixing agents, pigment dispersants, thickeners, flow improvers, defoamers, foam inhibitors, release agents, foaming agents, penetrants, coloring dyes, coloring pigments, A fluorescent whitening agent, an ultraviolet absorber, an antioxidant, an antiseptic, an antibacterial agent, a waterproofing agent, a wet paper strength enhancer, a dry paper strength enhancer, and the like can also be appropriately compounded.

As a method for coating the glossy layer, various apparatuses such as a blade coater, a roll coater, an air knife coater, a bar coater, a rod blade coater, a curtain coater, a short dwell coater, and a size press can be used. The amount of the glossy layer to be applied varies depending on the treatment method, the smoothness and size of the ink receiving layer, and the required gloss, but may be ² g / m ² or more.

In the present invention, as a method for imparting gloss, a cast coating method is used. The cast coating method according to the present invention is generally the same as the production method for cast coated paper for printing, and includes a direct method, a coagulation method, a rewet method (rewet method), and a precast method. In particular, the cast coating method for the ink jet recording sheet according to the present invention, the coating composition constituting the glossy layer is coated on a support, and the coated surface is heated while the coated surface is in a wet state. This is a method of contacting, pressing, drying and peeling off a mirror roll to form a replica of the mirror roll surface on a coated surface, and refers to a direct method or a rewet method. The direct method is a method in which the layer is coated and then pressed against a heated mirror roll in an undried state (wet state) and dried. The rewet method is a method in which the layer is coated and dried, and then water is applied. In this method, the layer is re-wetted with a liquid as a main component, pressed against a heated mirror surface, and dried. The surface roughness, the diameter, the pressure (linear pressure) at the time of pressing, and the coating speed of the mirror roll according to the method can be appropriately selected in the same manner as the production conditions of the commercially available cast coated paper.

Although it is not clear why the ink jet recording sheet of the present invention having the gloss receiving layer provided on the ink receiving layer improves the fixability of the pigment ink, the colored pigment in the pigment ink is coated on the surface of the gloss developing layer. It is considered that the colored pigment can be retained inside the coating layer by increasing the ink absorption of the ink receiving layer and increasing the ink permeability of the gloss expressing layer so that the colored pigment does not remain in the coating layer. More specifically, by including a water-soluble polyurethane resin in the lower ink-receiving layer, the binder in the gloss-developing layer can be reduced without lowering the gloss. It is considered that the colored pigment in the pigment ink can be retained inside the coating layer.

The pigment ink referred to in the present invention is a colored pigment,
It is a recording liquid composed of an aqueous medium and other additives. The additives can be appropriately selected within a range that does not adversely affect the recording properties, which is the purpose of the ink. Among the colored pigments, pigments used as black inks include CI Pigment Black 7 (Carbon Black), and pigments used as cyan inks include CI Pigment Blue 1 and C.I.
I.PigmentBlue2, CIigmentBlue15: 3, CIigmentBlue
As pigments used as magenta ink, such as 16, etc.,
CIPigmentRed5, CIPigmentRed48: 2, CIPigmentRed5
7: 1, CI Pigment Red 112, CI Pigment Red 122, etc., as a pigment used as a yellow ink, CI Pigment Y
ellow1, CIigmentYellow3, CIigmentYellow13, CI
Pigment Yellow 83 is a typical example, but is not particularly limited as long as it is a colored pigment capable of forming an aqueous ink.

As the aqueous medium, a mixture of water, a water-soluble organic solvent, a dispersant, and other additives as necessary is used. In this case, the water contains various ions. It is preferable to use deionized water instead of tap water or the like.

As the water-soluble organic solvent, methyl alcohol, ethyl alcohol, n-propyl alcohol,
Isopropyl alcohol, n-butyl alcohol, se
C 1-4 alkyl alcohols such as c-butyl alcohol and tert-butyl alcohol; ethylene glycol, propylene glycol, butylene glycol,
Diethylene glycol, triethylene glycol, etc., 2
Examples include alkylene glycols having an alkylene group containing from 6 to 6 carbon atoms, polyhydric alcohols such as glycerin, polyalkylene glycols, amides, ethers, and the like.

The dispersing agent is not particularly limited as long as it is a water-soluble resin.
(Meth) acrylic acid copolymer, alkylstyrene- (meth) acrylic acid copolymer, styrene- (meth) acrylic acid-alkyl (meth) acrylate copolymer,
Acrylic resins such as (meth) acrylic acid-alkyl (meth) acrylate copolymers, and alkali-neutralized water-soluble synthetic resins such as salts thereof, and water-soluble resins such as polyvinyl alcohol, polyvinylpyrrolidone, and carboxymethylcellulose , Rosin, shellac, casein and the like, water-soluble alkali-neutralized natural resins, various surfactants, and the like, and these can be used alone or in combination of two or more.

[0034] Further, as an additive, if necessary,
H adjusters, defoamers, preservatives, and the like can be used.

The ink jet recording sheet of the present invention can be used irrespective of the recording method, provided that the ink jet recording sheet is used in a method using pigment ink at the time of recording. For example, a heat-fusible substance, a heat-fusible ink containing a colored pigment as a main component, a resin film or high-density paper, an ink sheet coated on a thin support such as synthetic paper is heated from the back side,
An image receiving sheet for thermal transfer recording that transfers by melting ink;
Ink-jet recording sheet for heat-melting hot-melt ink for micro-liquid optimization and flight recording, image-receiving sheet corresponding to photosensitive pressure-sensitive donor sheet using microcapsules containing photopolymerizable monomer and colorless or colored pigment, etc. Can be used for

[0036]

EXAMPLES The present invention will be described below with reference to examples of the present invention, but the present invention is not limited to these examples. Further, “parts” and “%” shown in the examples are parts by weight and% by weight unless otherwise specified.

<Preparation of Support> Freeness 450 ml CSF
70 parts of LBKP, 450 ml of freeness NBKP of CSF
In 100 parts of 30 parts of wood pulp, the ratio of light calcium carbonate / heavy calcium carbonate / talc is 30/35.
/ 35 pigment, 1.0 part of commercially available cationic starch, 0.1 part of commercially available alkyl ketene dimer, 0.03 part of commercially available cationic acrylamide, and 0.5 part of sulfuric acid band, to adjust the pH of the pulp slurry to 8 .2. After the preparation, papermaking was performed using a Fourdrinier paper machine at a basis weight of 90 g / m ² to obtain a support. The thus obtained support was used in Examples and Comparative Examples described below.

Example 1 <Preparation of Ink Receiving Layer> 100 parts of synthetic amorphous silica (Mizukasil P-78D: manufactured by Mizusawa Chemical Industries, average particle size 8.0 μm), cationic aqueous polyurethane Using 25 parts of resin (F-8564D; manufactured by Daiichi Kogyo Seiyaku Co., Ltd., glass transition temperature (Tg) = 70 ° C.) and 25 parts of polyvinyl alcohol (Kuraray Povar 117: manufactured by Kuraray Co., Ltd.)
It was obtained by adjusting the solid content to 15%. Then, the coating composition was applied to the support using an air knife coater so as to have a dry coating amount of 10 g / m ² , thereby producing an ink receiving layer. <Preparation of Gloss-Producing Layer> The coating composition comprises colloid particles (S
T-40: Nissan Chemical Co., 100 parts, polyvinyl alcohol (Kuraray Povar 117: Kuraray Co., Ltd.) 20 parts, cation-modified polyvinyl alcohol (CM318: Kuraray Co., Ltd.) 3 parts, nonionic oleic acid emulsion as a release agent ( DEF7100: manufactured by Nissin Chemical Co., Ltd.) and adjusted to a solid concentration of 12%. The coating composition was applied on the ink receiving layer by a die coater so as to have an absolutely dry coating amount of 20 g / m ^2, and was applied to a mirror roll having a surface temperature of 50 ° C. at an application speed of 5 m / min. After pressing for 2 seconds and drying, a gloss-developing layer was prepared to obtain an ink jet recording sheet for a pigment ink of Example 1.

Example 2 100 parts of synthetic amorphous silica (Mizukasil P-78D: manufactured by Mizusawa Chemical Industries, average particle size 8.0 μm), anionic aqueous polyurethane resin (Superflex 150D;
25 parts of polyvinyl alcohol (Kuraray Povar 117: manufactured by Kuraray Co., Ltd.) 25
An ink jet recording sheet of Example 2 was obtained in the same manner as in Example 1, except that the coating composition containing the parts was used for the ink receiving layer.

Example 3 100 parts of synthetic amorphous silica (Mizukasil P-78D: manufactured by Mizusawa Chemical Industries, average particle size 8.0 μm), anionic aqueous polyurethane resin (Superflex 150HS;
Daiichi Kogyo Seiyaku, Tg = 32 ° C.) 25 parts, polyvinyl alcohol (Kuraray Povar 117: Kuraray) 25
The ink jet recording sheet of Example 3 was obtained in the same manner as in Example 1, except that the coating composition containing the parts was used for the ink receiving layer.

Example 4 100 parts of synthetic amorphous silica (Mizukasil P-78D: manufactured by Mizusawa Chemical Industries, average particle size 8.0 μm), anionic aqueous polyurethane resin (Hydran AP-40F; manufactured by Dainippon Ink Industries, Ltd.) (Tg = 49 ° C.) 25 parts, polyvinyl alcohol (Kuraray Povar 117: manufactured by Kuraray) 25
The ink jet recording sheet of Example 4 was obtained in the same manner as in Example 1 except that the coating composition containing the components was used for the ink receiving layer.

Example 5 100 parts of synthetic amorphous silica (Mizukasil P-78D: manufactured by Mizusawa Chemical Industries, average particle size 8.0 μm), anionic aqueous polyurethane resin (Superflex 126; manufactured by Daiichi Kogyo Seiyaku, Tg = 72 ° C), except that a coating composition containing 25 parts of polyvinyl alcohol (Kuraray Povar 117: manufactured by Kuraray Co., Ltd.) was used for the ink receiving layer.
In the same manner as in Example 1, an ink jet recording sheet of Example 5 was obtained.

Example 6 100 parts of synthetic amorphous silica (Mizukasil P-78D: manufactured by Mizusawa Chemical Industries, average particle size 8.0 μm), anionic aqueous polyurethane resin (Superflex 130; manufactured by Daiichi Kogyo Seiyaku, Tg = 96 ° C) An ink jet recording sheet of Example 6 was obtained in the same manner as in Example 1 except that 25 parts of polyvinyl alcohol (Kuraray Poval 117: manufactured by Kuraray Co., Ltd.) was used for the ink receiving layer.

Comparative Example 1 100 parts of synthetic amorphous silica (Mizukasil P-78D: manufactured by Mizusawa Chemical Industry Co., Ltd., average particle size 8.0 μm), anionic aqueous acrylic resin (Boncoat AN-011; Dainippon Ink Industries, Tg) = 25 ° C) Ink jet of Comparative Example 1 in the same manner as in Example 1 except that a coating composition containing 25 parts of polyvinyl alcohol (Kuraray Poval 117: manufactured by Kuraray Co., Ltd.) was used for the ink receiving layer. A recording sheet was obtained.

Comparative Example 2 100 parts of synthetic amorphous silica (Mizukasil P-78D: manufactured by Mizusawa Chemical Industry Co., Ltd., average particle size 8.0 μm), anionic aqueous acrylic resin (Boncoat AN-198; Dainippon Ink Industries, Tg = 35 ° C.) Ink jet of Comparative Example 2 in the same manner as in Example 1 except that a coating composition containing 25 parts of polyvinyl alcohol (Kuraray Povar 117: manufactured by Kuraray Co., Ltd.) was used for the ink receiving layer. A recording sheet was obtained.

Comparative Example 3 100 parts of synthetic amorphous silica (Mizukasil P-78D: manufactured by Mizusawa Chemical Industries, average particle size: 8.0 μm), anionic aqueous polyester resin (Vylonal MD1250; manufactured by Toyobo, Tg = 62 ° C.) An ink jet recording sheet of Comparative Example 3 was obtained in the same manner as in Example 1, except that a coating composition containing 25 parts of 25 parts of polyvinyl alcohol (Kuraray Povar 117: manufactured by Kuraray Co., Ltd.) was used for the ink receiving layer. Was.

Comparative Example 4 100 parts of synthetic amorphous silica (Mizukasil P-78D: manufactured by Mizusawa Chemical Industry Co., Ltd., average particle size 8.0 μm), anionic aqueous acrylic resin (Boncoat SK-105; Dainippon Ink Industries, Tg) = 100 ° C.) 25 parts of a coating composition containing 25 parts of polyvinyl alcohol (Kuraray Povar 117: manufactured by Kuraray Co., Ltd.) was used in the same manner as in Example 1 except that the ink-receiving layer was used. A recording sheet was obtained.

Comparative Example 5 100 parts of synthetic amorphous silica (Mizukasil P-78D: manufactured by Mizusawa Chemical Industries, average particle size 8.0 μm), anionic aqueous polyurethane resin (Superflex 300;
25 parts, polyvinyl alcohol (Kuraray Povar 117: manufactured by Kuraray Co., Ltd.) 2
An ink jet recording sheet of Comparative Example 5 was obtained in the same manner as in Example 1, except that the coating composition containing 5 parts was used for the ink receiving layer.

Comparative Example 6 A coating prepared by mixing 100 parts of synthetic amorphous silica (Mizukasil P-78D: manufactured by Mizusawa Chemical Industries, average particle size: 8.0 μm) and 50 parts of polyvinyl alcohol (Kuraray Poval 117: manufactured by Kuraray Co., Ltd.) Other than using the composition for the ink receiving layer,
In the same manner as in Example 1, an inkjet recording sheet of Comparative Example 6 was obtained.

Comparative Example 7 A coating prepared by mixing 100 parts of synthetic amorphous silica (Mizukasil P-78D: manufactured by Mizusawa Chemical Industries, average particle size: 8.0 μm) and 50 parts of polyvinyl alcohol (Kuraray Poval 117: manufactured by Kuraray). Using the composition, an ink receiving layer was provided in the same manner as in Example 1. The coating composition was applied on the obtained coated paper by a cast coating method. Colloidal particles (ST-40: Nissan Chemical) 100 were added to the coating composition.
Part, cationic aqueous polyurethane resin (F-8564)
D: manufactured by Daiichi Kogyo Seiyaku Co., Ltd., Tg = 70 ° C.) 23 parts, nonionic oleic acid emulsion (DEF7100:
A gloss developing layer was provided in the same manner as in Example 1 except that 1 part of Nisshin Chemical Co., Ltd. was used, and an ink jet recording sheet of Comparative Example 7 was obtained.

Comparative Example 8 A synthetic amorphous silica (Mizukasil P-78) was added to the coating composition.
D: Mizusawa Chemical Industries, average particle size 8.0 μm) 100
And 50 parts of polyvinyl alcohol (Kuraray Poval 117: manufactured by Kuraray Co., Ltd.). The coating composition was applied on the obtained coated paper by a cast coating method. 100 parts of colloid particles (ST-40: Nissan Chemical) were added to the coating composition,
Cationic waterborne polyurethane resin (Paterracol SH3
202: 23 parts manufactured by Dainippon Ink and Chemicals, Tg = 0 ° C), nonionic oleic acid emulsion (DEF710) as a release agent
0: manufactured by Nissin Chemical Co., Ltd.) except that one part was used, and a glossy layer was provided in the same manner as in Example 1 to obtain an ink jet recording sheet of Comparative Example 8.

Comparative Example 9 An ink jet recording sheet of Comparative Example 9 was obtained by forming only a cast coating layer on a support without providing an ink receiving layer in Example 1.

The ink jet recording sheet produced as described above was evaluated according to the following evaluation method.

<Preparation of Ink> The inks of the respective colors were mixed and ground with glass beads having a particle diameter of 1 mm using a horizontal bead mill by mixing the following components in respective proportions.
Coarse components were removed by a centrifugal separator, and the mixture was filtered through a membrane filter (pore size: 1 μm, manufactured by Toyo Filter Paper).

1. Black ink C.I.PigmentBlack7 (Carbon black) 6 parts Styrene- (meth) acrylic acid copolymer 6 parts Ethylene glycol 18 parts Ion exchange water 69.8 parts pH adjuster 0.2 parts 2. Pigment Blue 15: 3 (phthalocyanine blue G) 6 parts Styrene- (meth) acrylic acid copolymer 6 parts Ethylene glycol 18 parts Ion-exchanged water 69.8 parts pH adjuster 0.2 parts 3. Magenta Ink C.I. Pigment Red 112 (Naphthollet @FGR) 6 parts Styrene- (meth) acrylic acid copolymer 6 parts Ethylene glycol 18 parts Ion-exchanged water 69.8 parts pH adjuster 0.2 parts Yellow Ink C.I.Pigment Yellow 1 (Fast Yellow G) 6 parts Styrene- (meth) acrylic acid copolymer 6 parts Ethylene glycol 18 parts Ion-exchanged water 69.8 parts pH adjuster 0.2 parts

<Printing> The inks of the respective colors adjusted as described above were filled in an ink jet printer (DeskJet880C) manufactured by Hewlett-Packard Company, and the ink jet recording sheet was printed in black, cyan, magenta, yellow, and the other three colors except for the black ink. Solid printing is performed by printing a total of seven solid patterns of a total of two colors (red, green, blue) in color ink in a horizontal line of 2 cm x 2 cm square, and the solid pattern is fixed and water-resistant. Was used for evaluation.

<Fixing Property> 2 cm × 2 c of black ink
For the m square solid printing section, 24 hours after printing,
On the surface of the printing portion, lay silk paper (cleaning wiper "Dasper", manufactured by OZU), and place 1
6 cm square, 1.5mm thick plastic plate
Put a weight of 00g weight. Next, hold the edge of the silbon paper with your hand and gently pull it toward the non-printing area in the horizontal direction, and evaluate the ink tailing in the non-printing area of the printing area in contact with the plastic plate according to the following criteria. did. Pass is A,
B. A: No ink tailing is observed. B: Ink tailing is slightly observed, but peeling of the printing portion ink is not visible. C: Both ink tailing and peeling of the printing portion ink are visible. D: Ink tailing and peeling of the ink in the printing portion were severe, and the surface of the ink jet recording sheet in the printing portion was exposed.

<Ink Absorption> A4 size natural image was output, and the degree of ink absorption immediately after printing was visually evaluated.

◎: Completely absorbed. ：: Some ink remains, but there is no practical problem. Δ: The ink overflows in the solid printing portion. X: The ink overflows as a whole.

<Surface Gloss> The 75-degree specular gloss according to JIS P-8142 is "GM-26D" manufactured by Murakami Color Research Laboratory Co., Ltd.
It measured using.

The results are shown in Table 1.

[0062]

[Table 1] Sheet name Fixing property Specular gloss (%) Ink absorption example 1 A 65% ◎ Example 2 A 77% ○ Example 3 A 75% ◎ Example 4 A 68% ◎ Example 5 A 62 % ◎ Example 6 A 55% ◎ Comparative Example 1 D 43% △ Comparative Example 2 D 39% △ Comparative Example 3 C 22% ○ Comparative Example 4 C 15% ○ Comparative Example 5 D 82% × Comparative Example 6 D 70% × Comparative Example 7 D 55% × Comparative Example 8 D 57% × Comparative Example 9 D 12% ×

In Examples 1 to 7 in which an aqueous polyurethane resin having a glass transition temperature (Tg) of 20 ° C. or higher was used as the adhesive for the ink receiving layer provided on the support, the pigment was excellent in gloss and printed. An ink jet recording sheet having excellent ink fixability and ink absorbability was obtained.

Further, in Examples 1 to 5, the 75-degree specular glossiness according to JIS P-8142 on the gloss-developing layer side could be obtained at 60% or more, which was more excellent.

In Comparative Examples 1 to 4 in which an aqueous acrylic resin or an aqueous polyester resin was used as the adhesive for the ink-receiving layer provided on the support, the 75 ° mirror gloss was low, and the fixability and ink absorption of the pigment ink were low. Sex has also worsened.

In Comparative Example 5 in which an aqueous polyurethane having a glass transition temperature of 20 ° C. or less was used as the adhesive for the ink receiving layer provided on the support, 75 ° mirror gloss was excellent.
The fixability and ink absorbency of the pigment ink deteriorated.

In Comparative Example 6, in which the aqueous polyurethane was not used as the adhesive for the ink receiving layer provided on the support, the fixability and the ink absorbency of the pigment ink were deteriorated.

Comparative Example 7 in which an aqueous polyurethane having a glass transition temperature of 70 ° C. was used as an adhesive for a gloss-developing layer without using an aqueous polyurethane as an adhesive for an ink receiving layer provided on a support, and a glass transition temperature of 0 ° C. In Comparative Example 8 using the aqueous polyurethane, the fixability and the ink absorbency of the pigment ink were deteriorated.

In Comparative Example 8 in which only the gloss-developing layer was provided on the support, the 75-degree specular gloss was low, and the fixability and the ink absorption of the pigment ink were also deteriorated.

[0070]

According to the present invention, an ink jet recording sheet having excellent fixability and water resistance and high glossiness can be obtained in a printing portion ink after printing using an aqueous pigment ink.

Claims (3)

[Claims] 1. An ink jet recording method comprising: laminating an ink receiving layer and a gloss developing layer in this order on a support; pressing and drying the gloss developing layer to a mirror roll while the gloss developing layer is wet; A recording sheet for a pigment ink, wherein the ink receiving layer contains an aqueous polyurethane resin having a glass transition temperature (Tg) of 20 ° C. or higher. 2. The ink jet recording sheet for a pigment ink according to claim 1, wherein the aqueous polyurethane resin has a glass transition temperature in a range of 30 ° C. or more and 80 ° C. or less. 3. The JIS P-8142 on the glossy layer side
3. The ink jet recording sheet for a pigment ink according to claim 1, wherein the 75 ° specular glossiness is 60% or more.