JP2003341224A - Ink jet recording medium - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a swelling type ink jet recording medium which is excellent in ink fixing, ink absorption, glossiness and discoloration resistance properties. <P>SOLUTION: An ink jet recording medium having an ink accepting layer on a backing is characterized in that the ink accepting layer comprises at least a type of polyvinyl alcohol, a gelatin and a cationic polymer and that the pH at its outermost surface is 4.0 or lower. <P>COPYRIGHT: (C)2004,JPO

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 medium, and more particularly, to a swelling type ink jet recording medium excellent in ink fixing property, ink absorbing property, glossiness and discoloration resistance.

[0002]

2. Description of the Related Art Ink-jet recording has no noise, high-speed printing is possible, and it is easy to perform multicolor recording by using a plurality of ink nozzles. In recent years, it has rapidly spread as an information output device. Also, in the field of use, transparent films and glossy resin-coated paper are used as recording media, and the content of the output image is a color composition or design that requires image quality similar to photographs due to characters and figures. It is expanding to the image etc.

By the way, as the ink for ink jet recording, a water-based ink mainly containing water and a water-soluble organic solvent is used from the viewpoint of safety and recording characteristics, to prevent clogging of the ink and improve ejection characteristics. Etc. are planned. Further, as an inkjet recording medium (hereinafter, also simply referred to as a recording medium), a recording sheet in which a porous ink absorbing layer is provided on a support, which is conventionally called normal paper or inkjet recording paper, is used. Came.

However, these conventional recording media cannot meet the recent demand for high image quality because of large ink bleeding and low glossiness. Furthermore, when a conventional porous ink absorbing layer is used for a transparent film or glossy resin-coated paper, the porous ink absorbing layer has a low light transmittance, so that the transparency and glossiness are lost. . Further, when the ink absorption layer is non-porous, the light transmittance is improved, but since the water-based ink receptivity is poor, the ink remains on the surface of the recording medium for a long time after image recording and printing, and the dry fixing time There was a problem that it would be long.

In order to solve these problems, it has been proposed to use gelatin as an ink absorbing layer having a high light transmission property and an excellent receptivity for an aqueous ink. For example,
In JP-A-62-263084, a receiving layer formed from an aqueous gelatin solution having a specific pH is disclosed in JP-A-1-146784.
JP-A-6-64306 proposes the use of a mixture of gelatin and a surfactant, and JP-A-6-64306 proposes a recording sheet obtained by temporarily making gelatin into a gel state and then drying it by a cold dry method.

Certainly, the receptive layer using these gelatins has excellent ink receptivity and high light transmittance. However, it takes several minutes to tens of minutes in terms of the dry fixing time of the ink, and if it is touched with a hand or other paper immediately after the image recording and printing, these may be stained with the ink or the image itself may be soiled. There is a problem.

In general, the ink absorbing ability of a recording medium using gelatin in the ink receiving layer largely depends on the properties of the polymer used in the ink receiving layer. Polyvinyl alcohol is known as a conventionally used polymer having a high ink absorption ability, but when polyvinyl alcohol is used, there is a problem that the ink fixing property is lowered. Although this ink fixability is improved by using a cationic water-soluble polymer, it results in a new decrease in glossiness, and means for satisfying both excellent ink fixability and high glossiness at the same time. The situation is that has not appeared.

On the other hand, there is a problem that an ink jet recorded image is apt to cause discoloration due to harmful gas.
In particular, it is likely to occur with a phthalocyanine-based water-based dye used in a general color inkjet printer. Regarding the mechanism of this discoloration, all is not clear yet, but ozone, oxidant, SOx, NOx
It is speculated that a very small amount of active harmful gas in the air decomposes the dye.

[0009]

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and an object thereof is a swelling type ink jet recording excellent in ink fixability, ink absorbability, glossiness and fading resistance. To provide the medium.

[0010]

The above object of the present invention can be achieved by the following constitutions.

1. In an inkjet recording medium having an ink receiving layer on a support, the ink receiving layer contains at least one polyvinyl alcohol, gelatin and a cationic polymer, and the outermost film surface pH is 4.0 or less. An inkjet recording medium characterized by being present.

2. An ink jet recording medium having two or more ink receiving layers on a support, wherein at least one of the ink receiving layers contains at least one polyvinyl alcohol and gelatin, and the ink receiving layer farthest from the support. The polyvinyl alcohol content ratio of A is
An ink jet recording medium characterized in that the content of polyvinyl alcohol is higher than that of the ink receiving layer located on the support side of the ink receiving layer A.

3. In an inkjet recording medium having an ink receiving layer on a support, the ink receiving layer contains at least one polyvinyl alcohol and gelatin, and has a saponification degree of 92% or less and a weight average molecular weight of 2000 or more. An inkjet recording medium containing 10% by mass or more of the total polyvinyl alcohol content of the polyvinyl alcohol.

4. An inkjet recording medium having an ink receiving layer on a support, wherein at least one layer of the ink receiving layer contains at least one polyvinyl alcohol, gelatin and cellulose.

5. 5. The ink jet recording medium according to any one of items 2 to 4, which contains a cationic polymer.

6. 6. The inkjet recording medium as described in 1 or 5 above, which contains two or more kinds of cationic polymers.

7. 2. Two or more layers of the ink receiving layer contain a cationic polymer, and the ink receiving layer having the largest content of the cationic polymer contains at least one kind of polyvinyl alcohol.
The inkjet recording medium according to any one of items 5 and 6.

The details of the present invention will be described below. In the invention according to claim 1, in an ink jet recording medium having an ink receiving layer on a support, the ink receiving layer contains at least one polyvinyl alcohol, gelatin and a cationic polymer, and has an outermost surface. The film surface pH is 4.0 or less, and the film surface p
H is preferably 3.0 to 4.0, and more preferably 3.7 to 4.0.

When the film surface pH of the outermost layer exceeds 4.0, the transparency of the ink receiving layer decreases, and when it is less than 3.0, the ink absorbency decreases, which is not preferable.

In the present invention, there is no particular limitation on the method for obtaining a desired film surface pH, and when lowering the film surface pH, an acid such as citric acid, oxalic acid, hydrochloric acid, sulfuric acid, nitric acid, acetic acid or carbonic acid is used. Further, when raising the film surface pH, an alkaline agent such as sodium hydroxide, potassium hydroxide, sodium carbonate, sodium hydrogen carbonate, sodium acetate or the like can be used. Further, as another effective means, by adding a pH buffer acting as an acid, it is possible to suppress an increase in the pH of the film surface after printing even when absorbing an ink having a relatively high pH.

The pH buffer agent is preferably a weak acid, and examples thereof include boric acid, carbonic acid, and various organic acids. However, carbonic acid is inconvenient because it easily releases carbon dioxide gas in a low pH range and is likely to cause various failures during preparation of a coating solution or during coating. Preferred weak acids include boric acid and organic acids, but examples of the organic acid include non-volatile phthalic acid, terephthalic acid, salicylic acid, benzoic acid, sebacic acid, lauric acid, palmitic acid, ascorbic acid, and citric acid. Examples thereof include malic acid, lactic acid, succinic acid, oxalic acid, polyacrylic acid and benzylic acid.

The film surface pH of the surface of the ink receiving layer in the present invention is as defined by J. TAPPI Paper Pulp Test Method No
49-86 was measured by the method specified in
Approximately 5 pure water with a pH of 6.2-7.3 on the ink receiving layer surface
It is possible to measure by dropping 0 μl and pressing a flat electrode.

Next, each component of the ink receiving layer will be described. The ink jet recording medium of the present invention is characterized in that the ink receiving layer contains at least gelatin and polyvinyl alcohol as a water-soluble polymer.

As the gelatin, any gelatin derived from animal collagen can be used, but gelatin obtained from collagen derived from pig skin, cowhide or cow bone is preferable. The type of gelatin is not particularly limited, but lime-processed gelatin, acid-processed gelatin, derivative gelatin (for example, Japanese Patent Publication No. 38-4854, 39-55).
No. 14, No. 40-12237, No. 42-26345.
No. 2,525,753, 2,594,2
No. 93, No. 2,614,928, No. 2,763,63
No. 9, No. 3,118,766, No. 3,132,945
Issue 3, Issue 3,186,846, Issue 3,312,553
Derivative gelatins described in U.S. Pat. No. 6,861,414 and U.S. Pat. No. 103,189, etc., or can be used in combination.

The term "derivative gelatin" as used in the present invention means gelatin having an amino group, an imino group or a carboxyl group which gelatin has, and in the present invention, a gelatin having an amino group or an imino group substituted is particularly preferable. More preferably, amino group-substituted gelatin is used, and examples thereof include phenylcarbamoyl gelatin and phthalated gelatin.

In the present invention, the derivative gelatin obtained by substituting the amino group is, for example, US Pat.
No. 91,582, No. 2,614,928, No. 2,52
5,753 and the like.

In the present invention, useful substituents for obtaining a derivative gelatin by substituting an amino group are as follows: a: acyl group such as alkylacyl, arylacyl, acetyl and substituted or unsubstituted benzoyl, b: alkyl Sulfonyl groups such as sulfonyl and arylsulfonyl, c: carbamoyl groups such as alkylcarbamoyl and arylcarbamoyl, d: thiocarbamoyl groups such as alkylthiocarbamoyl and arylthiocarbamoyl, e: straight chain or branched alkyl having 1 to 18 carbon atoms Group, f: substituted or unsubstituted phenyl, naphthyl and pyridyl,
An aryl group such as aromatic heterocyclic such as furyl can be mentioned.

Of these, the derivative gelatin in the present invention is preferably one in which the amino group is substituted with an acyl group (-COR ¹ ) or a carbamoyl group (-CONR ¹ R ² ).

R ¹ of the acyl group or carbamoyl group is a substituted or unsubstituted aliphatic group (eg, an alkyl group having 1 to 18 carbon atoms, an allyl group, etc.), an aryl group or an aralkyl group (eg, a phenethyl group, etc.). And R ² is a hydrogen atom, an aliphatic group, an aryl group or an aralkyl group.

Particularly preferred in the present invention is R ¹
Is an aryl group and R ² is a hydrogen atom. Hereinafter, examples of the substituent of the amino group of the derivative gelatin used in the present invention will be shown, but the present invention is not limited thereto.

An example of the amino group substituent of the derivative gelatin is shown below.

[0032]

[Chemical 1]

In the derivative gelatin of the present invention, in order to quickly absorb the ink into the receiving layer, 60% or more of the total amount of at least one selected from the amino group and the imino group is a substituent capable of reacting with the amino group or the imino group. It is preferable to use those which have been previously substituted with groups, and it is particularly preferable to use a derivative gelatin in which 80% or more of the total amount of amino groups is substituted.

The jelly strength of the gelatin according to the present invention is 15 (by PAGI method, Bloom type jelly strength meter).
It is 0 g or more, preferably 200 to 300 g.

Next, polyvinyl alcohol will be described. The polyvinyl alcohol preferably used in the present invention includes, in addition to ordinary polyvinyl alcohol obtained by hydrolyzing polyvinyl acetate, modified polyvinyl alcohol such as cation-modified polyvinyl alcohol having terminals and anion-modified polyvinyl alcohol having an anionic group. Alcohol is also included.

The polyvinyl alcohol obtained by hydrolyzing vinyl acetate preferably has an average degree of polymerization of 1,000 or more, and particularly, the average degree of polymerization is 1500 to 50.
No. 00 is preferably used, and the saponification degree is 70 to 1
It is preferably 00%, particularly preferably 80 to 99.5%, but in the invention according to claim 3, polyvinyl alcohol having a saponification degree of 92% or less and a weight average molecular weight of 2000 or more is The content of polyvinyl alcohol is preferably 10% by mass or more, the saponification degree is 80 to 92%, and the weight average molecular weight is 2000 to 5000.
It is particularly preferable to contain 10 to 50% by mass of the total polyvinyl alcohol content.

By using the polyvinyl alcohol having the above characteristics, it is possible to realize high ink absorbency and prevent the ink transfer to the back surface even if the recording media are laminated after printing on the recording media. .

As the cation-modified polyvinyl alcohol, for example, as described in JP-A No. 61-10483, primary to tertiary amino groups and quaternary ammonium groups are added to the main chain or side chain of polyvinyl alcohol. Examples thereof include polyvinyl alcohol, which can be obtained by saponifying a copolymer of an ethylenically unsaturated monomer having a cationic group and vinyl acetate.

Examples of the ethylenically unsaturated monomer having a cationic group include trimethyl- (2-acrylamido-2,2-dimethylethyl) ammonium chloride and trimethyl- (3-acrylamido-3,3-dimethylpropyl). ) Ammonium chloride, N-vinylimidazole, N-vinyl-2-methylimidazole, N
-(3-dimethylaminopropyl) methacrylamide,
Hydroxylethyltrimethylammonium chloride, N, N, N-trimethyl- (3-methacrylamidopropyl) ammonium chloride, N- (1,1-dimethyl-3-dimethylaminopropyl) acrylamide and the like can be mentioned.

The ratio of the cation-modified group-containing monomer in the cation-modified polyvinyl alcohol is 0.1 to 10 mol%, preferably 0.2 to 5 mol% based on vinyl acetate.
Is.

As the anion-modified polyvinyl alcohol, for example, polyvinyl alcohol having an anionic group as described in JP-A No. 1-206088, JP-A Nos. 61-237681 and 63-3.
A copolymer of a vinyl alcohol and a vinyl compound having a water-soluble group as described in JP-A-07979 and a modified polyvinyl alcohol having a water-soluble group as described in JP-A-7-285265. To be

As the nonion-modified polyvinyl alcohol, for example, a polyvinyl alcohol derivative obtained by adding a polyalkylene oxide group to a part of vinyl alcohol as described in JP-A-7-9758, JP-A-8-25795. Examples thereof include block copolymers of a vinyl compound having a hydrophobic group and vinyl alcohol, which are described in Japanese Patent Laid-Open Publication No. 2003-242242.

As the polyvinyl alcohol, two or more kinds having different degrees of polymerization, weight average molecular weight, degree of saponification and kinds of modification can be used in combination.

According to the second aspect of the present invention, in an ink jet recording medium having two or more ink receiving layers on a support, at least one of the ink receiving layers contains at least one polyvinyl alcohol and gelatin. It is characterized in that the content ratio of polyvinyl alcohols in the ink receiving layer A which is the farthest from the support is higher than the content ratio of polyvinyl alcohols in the ink receiving layer located on the support side of the ink receiving layer A.

By adding a large amount of polyvinyl alcohol having a high absorption capacity for the organic solvent contained in the ink to the surface side, even when printing is performed using an ink having a large amount of organic solvent, High ink absorbency can be realized.

In the present invention, the content ratio of polyvinyl alcohols in the ink receiving layer A farthest from the support is higher than the content ratio of polyvinyl alcohols in the ink receiving layer located on the support side of the ink receiving layer A. However, more preferable embodiments are shown below, but the present invention is not limited thereto.

1. 1. A structure having a plurality of ink receiving layers, wherein the polyvinyl alcohol content of the outermost ink receiving layer is the highest, and the polyvinyl alcohol content of the ink receiving layers in the lower layers is sequentially lower. 2. A structure having a plurality of ink receiving layers, one layer containing polyvinyl alcohol, and the ink receiving layer below the layer does not contain polyvinyl alcohol at all. A structure having a plurality of ink receiving layers, only the outermost layer containing polyvinyl alcohol, and the other ink receiving layers containing no polyvinyl alcohol at all.

In the present invention, it is preferable that the ink receiving layer having two or more ink receiving layers and having the largest amount of ink dye adsorbed contains polyvinyl alcohol. As a method for improving the discoloration property of an inkjet image, it is necessary to protect the coloring material from an oxidizing gas such as oxygen, but in a swelling type recording medium, the coloring material is contained in the ink receiving layer as far away from the outside air as possible. Dyeing was an important requirement, but by this means alone, it is difficult to realize discoloration resistance comparable to silver salt photographic materials, and as a result of the inventors' intensive studies, The presence of polyvinyl alcohol, particularly a polyvinyl alcohol having a saponification degree of 92% or less and a weight average molecular weight of 2000 or more, in the vicinity of the dyed coloring material causes fading of oxygen and the like in these polyvinyl alcohols. Due to the promoting harmful gas blocking effect, good discoloration resistance is realized.

In the constitution according to the present invention, a particularly preferable constitution is that the cationic polymer-containing layer used as needed is a layer other than the outermost layer, and polyvinyl alcohol is used for the layer, and the above-mentioned effect is obtained by this constitution. It can be used most efficiently.

In the present invention, as the water-soluble polymer,
In addition to the above-mentioned gelatin and polyvinyl alcohol and the below-mentioned celluloses, known water-soluble polymers can be used in combination, for example, polyvinylpyrrolidones, polyacrylamide, polydimethylacrylamide, polydimethylaminoacrylate, vinyl alcohol acrylate. Acrylic group-containing polymers such as copolymer salts (see JP-A-60-168651 and JP-A-62-1988), starch, oxidized starch, carboxyl starch, dialdehyde starch,
Cationic starch, dextrin, gum arabic, casein, pullulan, dextran, polyethylene glycol, polyalkylene glycol such as polypropylene glycol, polyvinyl ether, polyglycerin, maleic acid alkyl vinyl ether copolymer, maleic acid N
-Synthetic polymers such as vinylpyrrole copolymer, styrene-maleic anhydride copolymer and polyethyleneimine (JP-A-61-32787, 61-237680 and 61-61)
No. 277483)) and the like.

In the ink jet recording medium of the present invention, the proportion of these water-soluble polymers in the ink receiving layer is preferably 1 to 30% by mass, more preferably 2%.
Is about 15% by mass.

Next, the cationic polymer will be described. The term "cationic polymer" as used in the present invention means a polymer whose main constituent is cationic in an aqueous solution, and typical examples thereof include JP-A-61-161887 and JP-A-61-161887.
63477, JP-A-5-104848, 5-12
Examples thereof include polymers containing primary, secondary, tertiary amino groups and quaternary ammonium salts described in Japanese Patent No. 4329. Any such water-soluble cationic polymer can be used, and the type thereof is not particularly limited, but the cationic polymers preferably used in the present invention include the following.

A) polyallylamine b) dicyandiamide condensate c) polyethyleneimine d) cation-modified PVA e) cation-modified PVP f) epichlorohydrin derivative g) amino group-substituted nylon h) represented by the following general formula [1] Polymer containing a constitutional unit derived from a monomer unit i) Polymer containing a constitutional unit derived from a monomer unit represented by the following general formula [2] j) Monomer represented by the following general formula [3] Polymer containing constitutional units derived from units

[0054]

[Chemical 2]

In the formula, R ¹ represents a hydrogen atom or a substituted or unsubstituted lower alkyl group, and Q represents an oxygen atom or —NH—. R ² , R ³ and R ⁴ each represent a substituted or unsubstituted lower alkyl group, and may be the same or different.
X ⁻ represents a halogen ion, a sulfonate anion, an alkylsulfonate anion, an acetate anion or an alkylcarboxylic acid anion. n represents 2 or 3.

R ⁵ , R ⁶ and R ⁷ each represent a substituted or unsubstituted lower alkyl group and may be the same or different. X ⁻ represents a halogen ion, a sulfonate anion, an alkylsulfonate anion, an acetate anion or an alkylcarboxylic acid anion. n represents 2 or 3.

R ⁸ , R ⁹ and R ¹⁰ each represent a substituted or unsubstituted lower alkyl group and may be the same or different. X ⁻ represents a halogen ion, a sulfonate anion, an alkylsulfonate anion, an acetate anion or an alkylcarboxylic acid anion. n represents 2 or 3.

The lower alkyl group represented by R ^{1 to} R ¹⁰ is preferably a methyl group or an ethyl group.

The polyallylamines referred to in the present invention are polyallylamine represented by the following general formula [4], polydiallylamine represented by the following general formula [5-1] or [5-2], and the following general formula [6] -1] or a polydiallylamine derivative represented by [6-2], or a polymer thereof.

[0060]

[Chemical 3]

In the general formula [4], n is 5 to 1000.
An integer of 0, X ₁ ⁻ represents a residue of an inorganic acid or an organic acid.

[0062]

[Chemical 4]

General formulas [5-1], [5-2], [6-
1] and [6-2], R ₁ and R ₂ each represent a hydrogen atom, a methyl group, an ethyl group or a hydroxyethyl group, X ₂ ⁻ represents an inorganic acid residue or an organic acid residue, and Y Represents a divalent linking group. Also, n / m = 9/1 to 2/8, l =
It is 5 to 10000.

Specific examples of the polydiallylamine derivative represented by the general formula [6-1] or [6-2] include SO represented by the general formula described in JP-A-60-83882.
Those containing _two groups as repeating units, copolymers with acrylamide described on page 2 of JP-A No. 1-9776, and represented by the general formula [6-1] or [6-2] of the present invention. Examples thereof include copolymers with polydiallylamine.

Specific examples of the dicyandiamide type condensate used in the present invention include a dicyandiamide formalin condensate and a polyalkylene polyamine dicyandiamide ammonium salt condensate, which are Sunfix 70 manufactured by Sanyo Kasei Co. and Nikafloc manufactured by Nippon Carbide Co. D
-1000, Nichia Kagaku Co., Ltd. Neofix F, Neofix RP-70Y and the like are commercially available.

The polyethyleneimines referred to in the present invention are:
It is a polymer obtained by polymerizing ethyleneimine or a derivative thereof, and a polyethyleneimine quaternary ammonium compound is particularly preferable. Specifically, JP-A-60-727
85 and 60-76386 are mentioned.

The cation-modified polyvinylpyrrolidone referred to in the present invention is a copolymer of vinylpyrrolidone and a monomer unit having a cationic group. Specific examples of the monomer unit having a cationic group include quaternized vinylimidazole, quaternized dialkylaminoethyl methacrylate, and methacrylamidopropyltrialkylammonium salt.

Specific examples of the epichlorohydrin derivative used in the present invention include polyamide epichlorohydrin resins, reaction products of epichlorohydrin and tertiary amines described on page 2 of JP-A-61-252189, and JP-A- Examples thereof include compounds of the general formula (II) described on page 4 of JP-A No. 62-259882.

These can be synthesized by a known method. Further, as commercially available products, there are Nalpoli-607 (manufactured by Nalco Chemical Co., Ltd.) and Polyfix 601 (manufactured by Showa High Polymer Co., Ltd.).

Specific examples of the amino group-substituted nylon used in the present invention are described on page 2 of JP-A-59-33179, and commercially available products include AQ nylon (trade name:
Made by Toray).

As the cationic polyaluminum hydroxide used in the present invention, those described in item 2 of JP-A-60-257286 can be used.

Preferred compounds among the monomers represented by the general formula [1] include, for example, N, N-dimethylaminoethyl (meth) acrylate, N, N-diethylaminoethyl (meth) acrylate and N, N-dimethylamino. Propyl (meth) acrylate, N, N-dimethylaminopropyl (meth) acrylate, N, N-dimethylaminoethyl (meth) acrylamide, N, N-diethylaminoethyl (meth) acrylamide, N, N-dimethylaminopropyl (meth ) Acrylamide and N, N
-Diethylaminopropyl (meth) acrylamide methyl chloride, ethyl chloride, methyl bromide, ethyl bromide, quaternary compounds of methyl iodide or ethyl iodide, or sulfonates, alkyl sulfonates, and acetates substituted with their anions. Alternatively, an alkylcarboxylic acid salt may be mentioned.
Of these, particularly preferable compounds include, for example, trimethyl-2- (methacryloyloxy) ethylammonium chloride, triethyl-2- (methacryloyloxy) ethylammonium chloride, trimethyl-2-
(Acryloyloxy) ethylammonium chloride, triethyl-2- (acryloyloxy) ethylammonium chloride, trimethyl-3- (methacryloyloxy) propylammonium chloride, triethyl-3- (methacryloyloxy) propylammonium chloride, trimethyl-2- (methacryloyl) Amino) ethylammonium chloride, triethyl-2
-(Methacryloylamino) ethylammonium chloride, trimethyl-2- (acryloylamino) ethylammonium chloride, triethyl-2- (acryloylamino) ethylammonium chloride, trimethyl-3- (methacryloylamino) propylammonium chloride, triethyl-3- ( Methacryloylamino) propyl ammonium chloride, trimethyl-3
-(Acryloylamino) propylammonium chloride, triethyl-3- (acryloylamino) propylammonium chloride, N, N-dimethyl-N-ethyl-2- (methacryloyloxy) ethylammonium chloride, N, N-diethyl-N-methyl -2-
(Methacryloyloxy) ethylammonium chloride, N, N-dimethyl-N-ethyl-3- (acryloylamino) propylammonium chloride, trimethyl-2- (methacryloyloxy) ethylammonium bromide, trimethyl-3- (acryloylamino)
Propyl ammonium bromide, trimethyl-2-
Examples thereof include (methacryloyloxy) ethylammonium sulfonate and trimethyl-3- (acryloylamino) propylammonium acetate.

Preferred examples of the monomer represented by the general formula [2] include trimethyl-p-vinylbenzylammonium chloride, trimethyl-m-vinylbenzylammonium chloride, triethyl-p-vinylbenzylammonium chloride and triethyl-m-vinyl. Benzyl ammonium chloride, N, N-dimethyl-N
-Ethyl-p-vinylbenzylammonium chloride, N, N-diethyl-N-methyl-p-vinylbenzylammonium chloride, trimethyl-p-vinylbenzylammonium bromide, trimethyl-m-vinylbenzylammonium bromide, trimethyl-p-
Vinylbenzyl ammonium sulfonate, trimethyl-m-vinyl benzyl ammonium sulfonate, trimethyl-p-vinyl benzyl ammonium acetate,
Examples thereof include trimethyl-m-vinylbenzylammonium acetate.

Preferred examples of the monomer represented by the general formula [3] include diallyldimethylammonium chloride, diallyldiethylammonium chloride, diallyldimethylammonium bromide, diallyldimethylammonium sulphate and diallyldimethylammonium acetate.

In addition to these monomer units, acrylamide, methacrylamide, N, N-dimethylacrylamide, N-isopropylacrylamide, diacetone acrylamide, N-methylol acrylamide, 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth). By copolymerizing a monomer selected from acrylate and N-vinylpyrrolidone in the range of 20 to 80 parts by mass, the ink absorption capacity and the ink absorption rate of the polymer having the quaternary ammonium salt group are increased, and the ink dot diameter is further increased. It is possible to impart extremely preferable properties such as adjusting to an appropriate size and eliminating uneven printing on the solid portion.

In the invention according to claim 6, it is preferable to use two or more kinds of the above-mentioned cationic polymers, and in the invention according to claim 7, 2 of the ink receiving layer is used.
The ink receiving layer containing at least one layer contains at least one cationic polymer, and the ink receiving layer having the most cationic polymer content is at least 1.
It is preferred to include a species of the above mentioned polyvinyl alcohols. The inkjet recording medium of the present invention having the above-mentioned constitution is preferable because the effect of the present invention can be further exhibited.

In the invention according to claim 4, in the ink jet recording medium having the ink receiving layer on the support, at least one layer of the ink receiving layer may contain cellulose in addition to the above-mentioned polyvinyl alcohol and gelatin. It is a feature. Usually, the solvent composition of an inkjet ink is mainly composed of water and a water-soluble organic solvent. When printing is performed on the recording medium having the above-mentioned configuration using the inks having these compositions, polyvinyl alcohol exhibits a high absorption ability with respect to an organic solvent, and celluloses have a high absorption ability with respect to water. By exerting the effect, it is possible to realize extremely good ink absorption as a total effect. In addition, as an environment for printing, stable ink absorbency can be obtained under a wide range of environmental conditions from low temperature and low humidity to normal temperature and normal humidity.

The cellulose that can be used in the present invention is preferably a water-soluble cellulose derivative, and examples thereof include water-soluble cellulose such as carboxymethyl cellulose (cellulose carboxymethyl ether), methyl cellulose, hydroxymethyl cellulose, hydroxyethyl cellulose and hydroxypropyl cellulose. Examples of the derivative include cellulose derivatives such as nitrocellulose, cellulose acetate propionate, cellulose acetate, and cellulose sulfate.

Next, other components of the recording medium other than the above-mentioned factors will be described. In the present invention, an appropriate cross-linking agent can act on the ink receiving layer for the purpose of improving water resistance. Specific examples of the cross-linking agent include aldehyde compounds such as formaldehyde and glutaraldehyde, ketone compounds such as diacetyl and chloropentanedione, bis (2-chloroethylurea), 2
-Hydroxy-4,6-dichloro-1,3,5-triazine, a compound having a reactive halogen as described in U.S. Pat. No. 3,288,775, divinyl sulfone, as described in U.S. Pat. No. 3,635,718. Compounds having a reactive olefin, N described in US Pat. No. 2,732,316
-Methylol compounds, isocyanates such as those described in U.S. Pat. No. 3,103,437, U.S. Pat. No. 3,017,28
No. 0, 2,983,611, aziridine compounds, US Pat. No. 3,100,704, carbodiimide compounds, US Pat. No. 3,091,537, epoxy compounds, mucochloric acid. Such as halogen carboxaldehydes and dioxane derivatives such as dihydroxydioxane.
A combination of two or more species can be used. The addition amount of the cross-linking agent is preferably 0.01 g to 10 g, and more preferably 0.1% to 100 g of the modified polyvinyl alcohol constituting the composition.
It is 1 to 5 g.

As the method for forming the ink receiving layer according to the present invention, a size press method, a roll coater method, a blade coater method, an air knife coater method, a gate roll coater method, a rod bar coater method, a curtain method, a slide hopper method, A commonly used coating method such as an extrusion method is used.

In the present invention, the ink receiving layer further includes a surfactant, a binder and a hardener, as well as an inorganic pigment, a coloring dye, a coloring pigment, an ink dye fixing agent, an ultraviolet absorber, an antioxidant and a pigment. Various known additives such as a dispersant, a defoaming agent, a leveling agent, a preservative, a fluorescent whitening agent, a viscosity stabilizer, and a pH adjusting agent can also be added.

In the present invention, for the purpose of improving the image quality, it is preferable to add a surfactant to the ink receiving layer within a range that does not impair the ink absorbability. The surfactant used may be any of anionic, cationic, nonionic, and betaine types, and may be a low molecular weight compound or a high molecular weight compound, or different types may be used in combination. More preferably, it is a fluorine-based surfactant.

As a conventional method of using a surfactant, it has been considered unfavorable that a combination of an anionic surfactant and a cationic surfactant causes aggregation in a solution state before coating, but it is not preferable. In the case of surfactants, there is no aggregation in a solution state, and when used in an inkjet recording sheet, it exhibits excellent ink receptivity, ink droplets do not diffuse over time, and larger droplets are used. It was found that an image having higher density and less unevenness can be obtained.

In the present invention, the anionic fluorochemical surfactant or the cationic fluorochemical surfactant is, for example, US Pat. Nos. 2,559,751 and 2,567,011.
Issue 2, Issue 2,732,398, Issue 2,764,602
Issue 2, Issue 2,806,866, Issue 2,809,998
Nos. 2,915,376, 2,915,528
No. 2, ibid. 2,918,501, ibid. 2,934,450
Issue 2, Issue 2,937,098, Issue 2,957,031
Issue 3, Issue 3,472,894, Issue 3,555,089
No., British Patent Nos. 1,143,927 and 1,130,8
No. 22, JP-B-45-37304, JP-A-47-96.
No. 13, No. 49-134614, No. 50-11770.
No. 5, No. 50-117727, No. 50-112243
No. 52-41182, No. 51-12392, British Chemical Society Journal (J. Chem. Soc.) 1950 27.
89, 1957, pages 2574 and 2640, American Chemical Society Journal (J. Amer. Chem. Soc.) 79: 2549 (1957), Oil Chemistry (J. Japan).
Oil Chemists Soc. ) Volume 12 653
Page, Journal of Organic Chemistry (J. Org. Chem.), Vol. 30, 3
It can be synthesized by the method described on page 524 (1965) or the like.

Some of these fluorine-based surfactants are trade names of Megafac F from Dainippon Ink and Chemicals, Inc., and Fluorad from Minnesota Mining and Manufacturing Company. Fluorad) FC, Imperial Chemical Industry Co., Monflor, Ei DuPont Nemeras & Co., Zonyls, and Falbeberke. Hoechst to Licovet V
It is marketed under the trade name PF.

The total amount of these cationic fluorochemical surfactants and anionic fluorochemical surfactants used is preferably 0.1 to 1000 mg per 1 m ² , and preferably 0.5 to 3 mg.
The amount is preferably 00 mg, more preferably 1.0 to 150 mg.
When used in combination, two or more of each may be used in combination. In addition, a nonionic fluorine-based surfactant, a betaine-type fluorine-based surfactant, and a hydrocarbon-based surfactant may be used in combination.

In the present invention, the addition ratio of the anionic fluorochemical surfactant and the cationic fluorochemical surfactant is
The molar ratio is preferably 1:10 to 10: 1, more preferably 3: 7.
~ 7: 3 is preferred.

The coating amount of the ink receiving layer according to the present invention is 3 to 100 g / m ² , more preferably 5 to 50 g / m ^2.
Is.

Although the ink receiving layer is provided on at least one side of the support, it may be provided on both sides of the support for the purpose of preventing curling.

In the present invention, a matting agent can be used in the ink receiving layer to prevent sticking.

Matting agents are well known in the photographic art and can be defined as discrete solid particles of an inorganic or organic material dispersible in a hydrophilic organic colloid binder. Examples of inorganic matting agents include oxides (eg, silicon dioxide, titanium oxide, magnesium oxide, aluminum oxide, etc.), alkaline earth metal salts (eg, sulfates and carbonates, such as barium sulfate and carbonate). Examples thereof include calcium, magnesium sulfate, calcium carbonate, etc., silver halide grains that do not form an image (such as silver chloride and silver bromide, and a small amount of iodine atoms may be added as a halogen component) and glass.

Examples of organic matting agents include starch, cellulose ester (eg, cellulose acetate propionate, etc.), cellulose ether (eg, ethyl cellulose, etc.), synthetic resin and the like. Examples of synthetic resins are water-insoluble or sparingly soluble synthetic polymers, such as alkyl (meth) acrylate, alkoxyalkyl (meth) acrylate, glycidyl (meth) acrylate,
(Meth) acrylamide, vinyl ester (eg vinyl acetate), acrylonitrile, olefin (eg ethylene), styrene, benzoguanamine / formaldehyde condensate, etc., alone or in combination, or with these, acrylic acid, methacrylic acid, α, β-unsaturated A polymer having a monomer component of a combination of dicarboxylic acid, hydroxyalkyl (meth) acrylate, sulfoalkyl (meth) acrylate, styrenesulfonic acid and the like can be used.

Other epoxy resin, nylon, polycarbonate, phenol resin, polyvinylcarbazole,
Polyvinylidene chloride or the like can also be used.

From the viewpoint of transportability, it is preferable that the weight average particle diameter is 3 to 20 μm, and the total mass (also referred to as coating amount) in the ink receiving layer is 10 to 100 mg / m ² . From the viewpoint of coating liquid stability, it is preferable to remove particles having a particle size of 3 μm or less and particles having a particle size of 20 μm or more in advance by classification.

As the support used in the present invention, either a transparent support or an opaque support can be used depending on the purpose of use.

As the transparent support, any of the conventionally known supports can be used, and examples thereof include films of polyester resin, cellulose acetate resin, acrylic resin, polycarbonate resin, polyvinyl chloride resin, polyimide resin, cellophane, celluloid and the like. is there. Among these, a polyester resin, particularly a polyethylene terephthalate film, is preferable from the viewpoint of rigidity and transparency of the support.

As the opaque support, high-quality paper, medium-quality paper,
Non-coated paper such as super calendered paper, glossy base paper, tracing paper, art paper, coated paper, coated paper such as lightweight coated paper, lightly coated paper, cast coated paper, plastic film, pigmented opaque Films, films such as foamed films, resin-coated papers, resin-impregnated papers, non-woven fabrics, cloths, and composites thereof can be used. Of these, resin-coated papers and various films are preferable from the viewpoint of glossiness and smoothness, and resin-coated papers, polyolefin resin-coated papers, and polyester films are more preferable from the viewpoint of touch and high-grade feeling.

The base paper constituting the resin-coated paper which is preferably used is not particularly limited, and commonly used paper can be used, but more preferably, for example, a smooth base paper used for a photographic support is used. preferable. As the pulp constituting the raw paper, one kind or a mixture of two or more kinds of natural pulp, recycled pulp, synthetic pulp and the like is used. Additives such as a sizing agent, a paper strength enhancer, a filler, an antistatic agent, an optical brightening agent and a dye, which are generally used in papermaking, are added to the base paper.

Furthermore, a surface sizing agent, a surface paper strength agent, a fluorescent whitening agent, an antistatic agent, a dye, an anchoring agent and the like may be applied to the surface.

The thickness of the base paper is not particularly limited,
It is preferable that the paper has good surface smoothness, such as being compressed by applying pressure with a calender or the like during or after paper making.

As the resin for the resin-coated paper, a polyolefin resin or a resin curable with an electron beam can be used.
The polyolefin resin is a homopolymer of olefin such as low density polyethylene, high density polyethylene, polypropylene, polybutene, polypentene or a copolymer of two or more olefins such as ethylene-propylene copolymer and a mixture thereof. Various densities and melt viscosity indexes (melt indexes) can be used alone or in combination.

In the resin of the resin-coated paper, white pigments such as titanium oxide, zinc oxide, talc and calcium carbonate, fatty acid amides such as stearic acid amide and arachidic acid amide, zinc stearate, calcium stearate, stearic acid. Aluminum, fatty acid metal salts such as magnesium stearate, antioxidants such as Irganox 1010 and Irganox 1076, blue pigments and dyes such as cobalt blue, ultramarine blue, cesianian blue and phthalocyanine blue, cobalt violet, fast violet, manganese purple It is preferable to add various additives such as magenta pigments and dyes, fluorescent whitening agents, and ultraviolet absorbers in an appropriate combination.

In the present invention, an aqueous ink is preferably used, and a recording liquid containing a colorant, a liquid medium and other additives is used. As the colorant, direct dye, acid dye,
Examples thereof include basic dyes, reactive dyes, and water-soluble dyes such as food dyes.

As the solvent of the aqueous ink, water and various water-soluble organic solvents such as methyl alcohol, ethyl alcohol, propyl alcohol, isopropyl alcohol, butyl alcohol, sec-butyl alcohol, t
ert-butyl alcohol, isobutyl alcohol, and other alkyl alcohols having 1 to 4 carbon atoms; amides such as dimethylformamide and dimethylacetamide; ketones and ketone alcohols such as acetone and diacetone alcohol; ethers such as tetrahydrofuran and dioxane; Polyalkylene glycols such as polyethylene glycol and polypropylene glycol; alkylene groups such as ethylene glycol, propylene glycol, butylene glycol, triethylene glycol, 1,2,6-hexanetriol, thiodiglycol, hexylene glycol and diethylene glycol having 2 to 2 alkylene groups. 6 alkylene glycols; glycerin, ethylene glycol methyl ether, diethylene glycol methyl (or ethyl) ether, triethyl Glycol, lower alkyl ethers of polyhydric alcohols such as mono-methyl ether,
Pyrrolidinones such as 2H-pyrrolidinone, 1-methyl-
Examples thereof include pyrrolidones such as 2-pyrrolidone and 2-pyrrolidone. Among these many water-soluble organic solvents,
Preferred are polyhydric alcohols such as diethylene glycol, lower alkyl ethers of polyhydric alcohols such as triethylene glycol monomethyl ether and triethylene glycol monoethyl ether, and pyrrolidones.

In the present invention, the solvent of the ink is preferably a mixed solvent of water and an organic solvent from the viewpoint of preventing clogging of the ink head nozzle. At this time, the mixing ratio of water and the organic solvent is 1 by mass. / 9 to 9/1 is preferable, and more preferably 4/6 to 9/1.

Other additives to the ink include, for example, pH adjusting agents, sequestering agents, fungicides, viscosity adjusting agents,
Surface tension adjusting agents, wetting agents, surfactants, rust preventives and the like can be mentioned.

[0107]

The present invention will be specifically described below with reference to examples, but the present invention is not limited thereto.

Example 1 << Preparation of recording medium >> Recording media 1 to 13 were prepared according to the following procedure.

[Preparation of Recording Medium 1] (Preparation of Support 1) Moisture content 6%, basis weight 200 g / m
Low density polyethylene having a density of 0.92 was applied to the back side of the photographic base paper of No. ² by an extrusion coating method in a thickness of 35 μm. Then, a low-density polyethylene containing 5.5% of anatase type titanium oxide and having a density of 0.92 was applied to the surface side by an extrusion coating method at a thickness of 40 μm to prepare a support 1 having both surfaces coated with polyethylene. . Corona discharge was applied to the front side to form an undercoat layer of polyvinyl alcohol at 0.03 g / m ² , and back side was also applied to form a latex layer at a rate of 0.12 g / m ² .

(Preparation of Ink Receptive Layer Coating Liquid 1) Lime-treated gelatin (KV-3000 manufactured by Konica Gelatin Co., Ltd.) 50 parts by mass Polyvinyl alcohol (Kuraray Industry Co., Ltd .: PVA235) 50 parts by mass Organic fine particle matting agent (Soken Chemical Co., Ltd.) Manufactured: MR-13G) 0.5 parts by mass Surfactant (Megafax F-120) 0.3 parts by mass The above additives were sequentially mixed to give a coating solution having a solid content of 8 parts.
An ink receiving layer coating liquid 1 was prepared by diluting with pure water so as to have a mass%.

(Coating) The above-prepared support 1 was coated with the above ink receiving layer coating solution 1 in a film weight of 8 g / dry.
A recording medium 1 was prepared by applying the coating solution by a bar coating method so that the recording medium 1 had a thickness of m ² , cooling it once to about 7 ° C., and then blowing it with air at 20 to 65 ° C. to dry it.

The film surface pH of the above-prepared recording medium 1 is
J. According to the method specified in TAPPI Paper Pulp Test Method No. 49-86, about 50 μl of pure water was dropped on the surface of the recording medium, and a flat electrode was pressed against the result to measure 4.5.
Met.

[Preparation of Recording Medium 2] A recording medium 2 was prepared in the same manner as in the preparation of the recording medium 1 except that the following ink receiving layer coating liquid 2 was used in place of the ink receiving layer coating liquid 1. .

(Preparation of Ink Receptive Layer Coating Liquid 2) Lime-treated gelatin (KV-3000 manufactured by Konica Gelatin Co., Ltd.) 50 parts by mass Polyvinyl alcohol (Kuraray Industries Co., Ltd .: PVA235) 45 parts by mass Cationic polymer PAA-HCl (poly Acrylic amine hydrochloride Nittobo) 5 parts by weight Organic fine particle matting agent (Soken Chemical Co., Ltd .: MR-13G) 0.5 parts by weight Surfactant (Megafax F-120) 0.3 parts by weight Sequentially mix until the solid concentration of the coating liquid is 8
An ink receiving layer coating liquid 2 was prepared by diluting with pure water so as to be a mass%.

The film surface pH of the recording medium 2 was 4.5. [Production of Recording Mediums 3 to 5] In the production of the above recording medium 2, the following cationic polymers were used in place of the cationic polymer PAA-HCl used in the ink receiving layer coating liquid 2 in the same manner as described above. Recording media 3 to 5 were produced.

Recording Medium 3: PAS-H (Polydimethyldiallylammonium Chloride Nitto Boseki) Recording Medium 4: Gohsenol CM-318 (Cation Modified Polyvinyl Alcohol Nippon Synthetic Chemical Industry) Recording Medium 5: CP-1 Recording Medium Prepared Above The film surface pHs of 3 to 5 were all 4.5.

[0117]

[Chemical 5]

[Production of Recording Mediums 6-9] Recording Medium 2
In the preparation of ~ 5, so that the film surface pH is 3.9,
Recording media 6 to 9 were prepared in the same manner except that an appropriate amount of citric acid in each ink receiving layer coating liquid was added.

[Production of Recording Mediums 10 to 13] In the production of the above recording media 2 to 5, except that an appropriate amount of citric acid in each ink receiving layer coating solution was added so that the film surface pH was 3.4. Recording media 10 to 13 were manufactured in the same manner.

PVA in Table 1 is an abbreviation for polyvinyl alcohol. << Evaluation of Recording Medium >> For each recording medium prepared above,
Using an inkjet printer (MJ-5000C; manufactured by Seiko Epson Corporation), yellow (Y), magenta (M), cyan (C), blue (B), green (G), red (R), black (K). Each of the dedicated inks was used to print at the maximum density for each color, and the following items were evaluated.

<Evaluation of Fixability> A uniform image having the highest density of blue (B), green (G), red (R) and black (K) is printed, and printed for 1 minute, 3 minutes, 5 minutes,
After 10 minutes, commercially available high-quality paper was overlaid, and the degree of transfer of the ink to the high-quality paper was visually observed, and the fixing property was judged according to the following criteria. ◎: A slight transfer of K was recognized after 1 minute. However, after 3 minutes and 5 minutes, there is no transfer and no problem in practical use. ○: B, G, R, and K are slightly transferred after 3 minutes, but after 5 minutes and 10 minutes, there is no problem. No transfer and no problem in practical use Δ: Transfer of any of B, G, R, and K is observed after 5 minutes, but no transfer occurs after 10 minutes, and practically acceptable limit level x: Even after 10 minutes , B, G, R, and K are not recognized for practical use.

<Evaluation of Glossiness> The glossiness of the surface of the unprinted portion and the image portion of the black ink printed image was visually observed, and the glossiness was evaluated according to the following criteria.

⊚: Good glossiness before and after printing and no problem at all ○: Glossiness before and after printing, no problem level Δ: Before and after printing The glossiness is slightly different, but there is no problem in practical use. X: Each of the evaluation results obtained by the above, which is inferior in glossiness before and after printing and is not in the practically acceptable level, is shown in Table 1.

[0124]

[Table 1]

As is clear from Table 1, a recording medium containing polyvinyl alcohol, gelatin and a cationic polymer as the ink receiving layer having the constitution according to the present invention, and having the outermost film surface pH of 4.0 or less. It can be seen that is superior in fixing property and gloss to the comparative example.

Example 2 << Preparation of Recording Media >> Recording media 21 to 26 were prepared according to the following procedure.

[Preparation of Recording Medium 21] The recording medium 21 was prepared by performing simultaneous multilayer coating on the support 1 prepared in Example 1 with a curtain coater.

(First Layer: Bottom Layer) Lime-treated gelatin (KV-3000 manufactured by Konica Gelatin) 1.2 g / m ² Polyvinylpyrrolidone K-90 (manufactured by BASF) 0.8 g / m ² (second layer) Lime-treated gelatin (KV-3000 manufactured by Konica Gelatin Co., Ltd.) 5.0 g / m ² Polyvinylpyrrolidone K-90 (manufactured by BASF) 3.0 g / m ² Polyurethane F-8438D (manufactured by Daiichi Kogyo Kagaku Co., Ltd.) 2.0 g / m ² (third layer: outermost layer) lime-treated gelatin (KV-3000 manufactured by Konica Gelatin Co., Ltd.) 0.5 g / m ² polyvinylpyrrolidone K-90 (manufactured by BASF) 0.4 g / m ² polyurethane F-8438D (No. 0.4 g / m ² organic fine particle matting agent (Soken Chemical Co., Ltd .: MR-13G) 60 mg / m ² Surfactant (Megafax F-120) 26 mg / m ² [Production of Recording Medium 22] Recording medium 22 was produced by performing simultaneous multilayer coating of the following layers on the support 1 produced in Example 1 using a curtain coater.

(First Layer: Bottom Layer) Lime-treated gelatin (KV-3000 manufactured by Konica Gelatin) 1.2 g / m ² Polyvinylpyrrolidone K-90 (manufactured by BASF) 0.8 g / m ² (second layer) Lime-treated gelatin (KV-3000 manufactured by Konica Gelatin) 5.0 g / m ² Polyvinylpyrrolidone K-90 (manufactured by BASF) 2.0 g / m ² Polyvinyl alcohol (manufactured by Kuraray Industries Co., Ltd .: PVA235) 1.0 g / m ² Polyurethane F-8438D (manufactured by Daiichi Kogyo Kabushiki Kaisha) 2.0 g / m ² (third layer: outermost layer) Lime-treated gelatin (KV-3000 manufactured by Konica Gelatin Co., Ltd.) 0.5 g / m ² Polyvinylpyrrolidone K-90 (manufactured by BASF) 0.4g / m ² polyurethane F-8438D (first industrial chemicals Co., Ltd.) 0.4g / m ² organic fine particle matting agent (Soken chemical Co., Ltd.: MR- 3G) 60mg / m ² surfactant (on Megafax F-120) 26mg / m ² support 1 prepared in Example 1 [Preparation of recording medium 23], a simultaneous multilayer coating layers below in a curtain coater Then, the recording medium 23 was manufactured.

(First Layer: Bottom Layer) Lime-treated gelatin (KV-3000 manufactured by Konica Gelatin) 1.2 g / m ² Polyvinylpyrrolidone K-90 (manufactured by BASF) 0.8 g / m ² (second layer) Lime-treated gelatin (KV-3000 manufactured by Konica Gelatin) 5.0 g / m ² Polyvinylpyrrolidone K-90 (manufactured by BASF) 2.75 g / m ² Polyvinyl alcohol (Kuraray Industries Co., Ltd .: PVA235) 2.00 g / m ² Polyurethane F-8438D (manufactured by Dai-ichi Kogyo Kabushiki Kaisha) 2.0 g / m ² (third layer: outermost layer) Lime-treated gelatin (KV-3000 manufactured by Konica Gelatin) 0.5 g / m ² Polyvinyl alcohol (Kuraray Industry) Co., Ltd.: PVA235) 0.4g / m ² polyurethane F-8438D (first industrial chemicals Co., Ltd.) 0.4g / m ² organic fine particle matting agent (total Chemical Co.: MR-13G) 60mg / m 2 surfactant (on Megafax F-120) 26mg / m ² support 1 prepared in Example 1 [Preparation of recording medium 24], curtain layers below The recording medium 24 was manufactured by performing simultaneous multilayer coating with a coater.

(First Layer: Bottom Layer) Lime-treated gelatin (KV-3000 manufactured by Konica Gelatin) 1.2 g / m ² Polyvinylpyrrolidone K-90 (manufactured by BASF) 0.8 g / m ² (second layer) Lime-treated gelatin (KV-3000 manufactured by Konica Gelatin Co., Ltd.) 5.0 g / m ² Polyvinylpyrrolidone K-90 (manufactured by BASF) 3.0 g / m ² Polyurethane F-8438D (manufactured by Daiichi Kogyo Kagaku Co., Ltd.) 2.0 g / m ² polyethylene glycol 20000 (manufactured by Merck) 1.0 g / m ² (third layer: outermost layer) lime-treated gelatin (KV-3000 manufactured by Konica Gelatin) 0.5 g / m ² polyvinyl alcohol (manufactured by Kuraray Industries Co., Ltd.) : PVA235) 1.2g / m ² organic particulate matting agent (Soken chemical Co., Ltd.: MR-13G) 60mg / m 2 surfactant (Megafax F-120 In the preparation of the recording medium 24 Preparation of recording medium 25] 26 mg / m ^2, as the cationic polymer in the third layer, in the same manner except that the CP-1 was added 0.4 g / m ^2, the recording medium 2
5 was produced.

[Preparation of Recording Medium 26] Recording Medium 23
In the preparation of, as a cationic polymer in the third layer,
In the same manner except that CP-1 was added at 0.4 g / m ² ,
The recording medium 26 was produced.

<< Evaluation of Recording Medium >> An inkjet printer (MJ-500) was used for each recording medium prepared above.
0C; manufactured by Seiko Epson Co., Ltd.) was loaded with the following two types of cyan ink having different solvent concentrations, a solid image with a cyan concentration was printed by changing the ink ejection amount, and the ink absorbency ( Ink overflow was evaluated.

[Preparation of Cyan Ink] (Cyan Ink 1) 6 parts by mass of Light Green SF yellowish diethylene glycol 47 parts by mass of water 47 parts by mass of cyanide (Cyan Ink 2) 6 parts by mass of light green SF yellowish 23.5 parts by mass of diethylene glycol 23.5 parts by mass [Evaluation of ink absorbency] ⊚: No uneven density unevenness is observed in the entire ink discharge amount range ○: Small uneven density unevenness is observed in the region where the ink discharge amount is large However, there is no problem. Δ: Coddle-like density unevenness is observed in the area with a large amount of ink ejection, but it is in a practically acceptable range. ×: Coddy-like density unevenness is observed in the entire ink ejection amount area. Table 2 shows the results obtained by the above because the quality is a problem in practical use.

[0135]

[Table 2]

As is clear from Table 2, the recording medium in which the content ratio of polyvinyl alcohols in the ink receiving layer of the third layer (outermost layer) of the present invention is higher than the content ratio of polyvinyl alcohols in the second layer. In comparison with the comparative example, it can be seen that the ink absorbability is good even when an ink having a high solvent ratio is used, and the occurrence of uneven density unevenness is small.

Example 3 << Preparation of Recording Media 31 to 38 >> In the recording media 24 and 25 prepared in Example 2, the saponification degree shown in Table 3 was used in place of the polyvinyl alcohol (PVA235) used in the third layer. And recording mediums 31 to 31 in the same manner except that polyvinyl alcohols having different weight average molecular weights are combined.
38 was produced.

<< Evaluation of Recording Medium >> An inkjet printer (MJ-500) was used for each recording medium prepared above.
0C; manufactured by Seiko Epson Co., Ltd.) was charged with two kinds of cyan ink having different solvent concentrations described in Example 2, and
The ink absorbency was evaluated in the same manner as described in 1 above, and the transferability was evaluated according to the following method, and the obtained results are shown in Table 3.

(Evaluation of Ink Transfer Resistance) Cyan ink 1 was used in the above ink jet printer to perform printing under the highest ejection conditions, and after storing at 23 ° C. and 65% relative humidity for 30 minutes, 80 g / m ² of high quality paper was printed. 200 sheets were stacked and stored for one day and night, and the ink transfer resistance was evaluated according to the following criteria.

⊚: No transfer at all ∘: Slightly traces of dye transfer remain, but the image itself hardly changes Δ: Transfer traces are large, and the surface of the image becomes devitrified ×: Paper and ink receiving layer Table 3 shows the respective evaluation results obtained by the above because the adhesiveness with and the paper cannot be peeled off neatly.

[0141]

[Table 3]

As is clear from Table 3, as the polyvinyl alcohol used in the third layer, polyvinyl alcohol having a saponification degree of 92% or less and a weight average molecular weight of 2,000 or more was used as 10% of the total polyvinyl alcohol content. It can be seen that the recording medium containing at least mass% is excellent in ink absorption and ink transfer properties.

Example 4 << Preparation of Recording Media >> Recording media 41 to 45 were prepared according to the following procedure.

[Preparation of Recording Medium 41] The recording medium 41 was prepared by performing simultaneous multilayer coating on the support 1 prepared in Example 1 with a curtain coater.

(First Layer: Bottom Layer) Lime-treated gelatin (KV-3000 manufactured by Konica Gelatin Co., Ltd.) 1.2 g / m ² Polyvinylpyrrolidone K-90 (manufactured by BASF) 0.8 g / m ² (second layer) Lime-treated gelatin (KV-3000 manufactured by Konica Gelatin Co., Ltd.) 5.0 g / m ² Polyvinylpyrrolidone K-90 (manufactured by BASF) 3.0 g / m ² Polyurethane F-8438D (manufactured by Daiichi Kogyo Kagaku Co., Ltd.) 2.0 g / m ² polyethylene glycol 20000 (manufactured by Merck) 1.0 g / m ² (third layer: outermost layer) lime-treated gelatin (KV-3000 manufactured by Konica Gelatin) 1.7 g / m ² organic fine particle matting agent (Soken Chemical Co., Ltd.) Manufacturing: MR-13G) 60 mg / m ² surfactant (Megafax F-120) 26 mg / m ² [Preparation of recording medium 42] A recording medium 42 was manufactured in the same manner except that the structure of the three layers was changed as follows.

(Third Layer: Outermost Layer) Lime-treated gelatin (KV-3000 manufactured by Konica Gelatin Co., Ltd.) 1.0 g / m ² carboxymethyl cellulose 0.7 g / m ² Organic fine particle matting agent (manufactured by Soken Chemical Co., Ltd .: MR-13G) ) 60 mg / m ² surfactant (Megafax F-120) 26 mg / m ² [Preparation of recording medium 43] In the preparation of the recording medium 41, the same procedure was performed except that the configuration of the third layer was changed as follows. Thus, the recording medium 43 was produced.

(Third Layer: Outermost Layer) Lime-treated gelatin (KV-3000 manufactured by Konica Gelatin Co., Ltd.) 1.0 g / m ² Polyvinyl alcohol (Kuraray Industries Co., Ltd .: PVA235) 0.7 g / m ² Organic fine particle matting agent (Soken Chemical Co., Ltd .: MR-13G) 60 mg / m ² Surfactant (Megafax F-120) 26 mg / m ² [Preparation of Recording Medium 44] In the preparation of the recording medium 41, the constitution of the third layer is as follows. A recording medium 44 was prepared in the same manner except that the above was changed.

(Third Layer: Outermost Layer) Lime-treated gelatin (KV-3000 manufactured by Konica Gelatin Co., Ltd.) 0.5 g / m ² Polyvinyl alcohol (Kuraray Industries Co., Ltd .: PVA235) 0.7 g / m ² Carboxymethyl cellulose 0. 5 g / m ² Organic fine particle matting agent (Soken Chemical Co., Ltd .: MR-13G) 60 mg / m ² Surfactant (Megafax F-120) 26 mg / m ² [Preparation of recording medium 45] In preparation of the recording medium 41 A recording medium 45 was manufactured in the same manner except that the configuration of the third layer was changed as follows.

(Third Layer: Outermost Layer) Lime-treated gelatin (KV-3000 manufactured by Konica Gelatin Co., Ltd.) 0.5 g / m ² polyvinyl alcohol (Kuraray Industries Co., Ltd .: PVA235) 0.7 g / m ² carboxymethyl cellulose 5 g / m ² CP-1 0.1 g / m ² Organic fine particle matting agent (Soken Chemical Co., Ltd .: MR-13G) 60 mg / m ² Surfactant (Megafax F-120) 26 mg / m ² << Evaluation of recording medium >> For each recording medium prepared above,
Cyan ink 1 described in Example 2 in an inkjet printer (MJ-5000C; manufactured by Seiko Epson Corporation).
, 16 ° C, 30% RH and 30 ° C, 70% RH
In the environment described above, a solid image of cyan density was printed by changing the ink discharge amount, the ink absorbency (ink overflow) was evaluated according to the method described in Example 2, and the obtained results are shown in Table 4. Shown in.

[0150]

[Table 4]

As is clear from Table 4, the recording medium containing gelatin, polyvinyl alcohols and celluloses in the same layer always has stable ink absorbability even when the environment for printing is different. I was able to confirm that

Example 5 << Preparation of Recording Medium >> In the preparation of the recording medium 21 described in Example 2, the amount of lime-processed gelatin in the third layer was 3.0 g /
In Table 5, polyvinyl alcohol (Kuraray Industries Co., Ltd .: PVA235), cationic polymer (PAS-H), and cationic polymer (CP-1) were used for the second layer and the third layer in place of m ^2. Recording media 51 to 59 were produced in the same manner except that the combinations described above were added. In the layer to which polyvinyl alcohol was added, the amount of polyvinyl pyrrolidone added was reduced according to the amount added.

<< Evaluation of Recording Medium >> An inkjet printer (MJ-500) was used for each recording medium prepared above.
0C; manufactured by Seiko Epson Co., Ltd.) was charged with the cyan ink 1 described in Example 2, and a solid image was printed at a density of about 1.0 as the cyan density, and the color fading resistance according to the following method was applied. The evaluation was performed and the obtained results are shown in Table 5.

(Evaluation of Fading Resistance to Discoloration) Each solid print image area printed by the above method was attached to a window in an office room and left for 6 months in an environment exposed to the external air flow but not exposed to direct sunlight. The reflection density of the printed part before and after standing was measured with red monochromatic light, the residual density ratio was calculated according to the following formula, and the fading resistance was evaluated according to the following criteria.

Concentration residual ratio = (concentration after standing for 6 months / concentration before standing) × 100 (%) ⊚: The residual concentration is 95% or more. ○: The residual concentration is 85% or more, 95%. Less than: Δ: residual density is 75% or more and less than 85% ×: residual density is less than 75%

[0156]

[Table 5]

As is clear from Table 5, two layers of the ink receiving layer contain a cationic polymer, and the ink receiving layer having the highest content of the cationic polymer contains polyvinyl alcohols. Is excellent in resistance to discoloration against oxidizing gas.

[0158]

According to the present invention, it is possible to provide a swelling type ink jet recording medium which is excellent in ink fixing property, ink absorbing property, glossiness and discoloration resistance.

Claims (7)

[Claims] 1. An ink jet recording medium having an ink receiving layer on a support, wherein the ink receiving layer contains at least one polyvinyl alcohol, gelatin and a cationic polymer, and has a pH of the outermost film surface. 4.
An inkjet recording medium, which is 0 or less. 2. An inkjet recording medium having two or more ink receiving layers on a support, wherein at least one of the ink receiving layers contains at least one polyvinyl alcohol and gelatin, and An ink jet recording medium, wherein the content ratio of polyvinyl alcohols in the furthest ink receiving layer A is higher than the content ratio of polyvinyl alcohols in the ink receiving layer located on the support side of the ink receiving layer A. 3. An inkjet recording medium having an ink receiving layer on a support, wherein the ink receiving layer contains at least one polyvinyl alcohol and gelatin and has a saponification degree of 92% or less and a weight. Average molecular weight is 2
An inkjet recording medium comprising polyvinyl alcohols of 000 or more in an amount of 10 mass% or more of the total polyvinyl alcohol content. 4. An ink jet recording medium having an ink receiving layer on a support, wherein at least one layer of the ink receiving layer is at least one polyvinyl alcohol,
An ink jet recording medium containing gelatin and celluloses. 5. The ink jet recording medium according to claim 2, further comprising a cationic polymer. 6. The ink jet recording medium according to claim 1, which contains two or more kinds of cationic polymers. 7. The ink receiving layer comprises two or more layers containing a cationic polymer, and the ink receiving layer having the largest content of the cationic polymer contains at least one kind of polyvinyl alcohol. Claim 1,
7. The inkjet recording medium according to any one of 5 and 6.