JP2006001231A - Coating liquid for inkjet recording medium - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a coating liquid for an inkjet recording medium for manufacturing a recorded matter having a high image quality, which has been difficult to manufacture by the conventional techniques, and simultaneously being excellent in storage stability of an image such as light resistance, water resistance and abrasion resistance at a high productivity, the manufacturing method of an inkjet recording medium, in which the coating liquid for the inkjet recording medium is employed, and the inkjet recording medium. <P>SOLUTION: This coating liquid for the inkjet recording medium is used for manufacturing the inkjet recording medium, in which at least one ink receiving layer is provided on at least one side of a support and includes a polymeric compound (A), which is hydrophilic in a temperature range, which is lower by a fixed temperature than that of a gelatin, (or a temperature sensing point) and hydrophobic in a temperature range exceeding the temperature sensing point. In addition, the manufacturing method of the inkjet recording medium, in which the coating liquid for the inkjet recording medium is employed, and the inkjet recording medium are dealt. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an ink jet recording medium using water-based ink, and more particularly to an ink jet recording medium that absorbs a solvent of an ink using a polymer compound, and in particular, image sharpness, resolution and uniformity, and printing. The present invention relates to an ink jet recording medium which is excellent in the adsorptivity and drying property of a water-based ink immediately afterwards, is excellent in pigment ink suitability, and has little quality deterioration during long-term storage.

The ink jet recording system has been used in a wide range of fields because it has low noise during recording, can be easily colored, and can perform high-speed recording.
In recent years, the development of inkjet recording media technology to obtain high image quality comparable to that of silver salt photographs has progressed, and microvoids formed by inorganic fine particles on a highly smooth support such as paper or polymer film coated with polyolefin. A recording medium provided with an ink-receiving layer having the above is commercially available as approaching photographic image quality. However, if a sufficient ink absorption capacity is to be ensured by only a minute gap in the ink receiving layer on a support having no ink absorbability, a very thick ink receiving layer of 35 μm or more must be formed. In order to obtain an ink-receiving layer having the thickness, a coating liquid several times thicker than that is coated with a uniform thickness, and the recording medium can be efficiently produced while maintaining the uniformity of the film thickness even in the drying process. Although it is required to be manufactured, at the present time it is difficult and problematic to achieve. Furthermore, in order to protect the global environment in recent years, it has been required to use water as a solvent for the coating solution, and water generally takes a long time to dry compared with organic solvents, and the problem is more A prominent and effective solution is needed.

Furthermore, when recording is performed using ink (dye ink) using a dye that is widely used at present, the image recorded by the action of the inorganic fine particles used for forming the fine voids described above is sunlight or the like. There is a problem of fading due to the light of the light and a problem that the dye is exposed to an oxidizing gas (such as ozone or nitrogen oxide) in the air due to the presence of minute voids.
In addition to the above-described type of ink jet recording medium that absorbs ink in microscopic voids (microscopic void type recording medium), the type of ink jet recording medium that absorbs ink using a water-soluble polymer compound (swelling type recording medium) There are many proposals for the latter method. For example, Patent Document 1 uses polyvinyl alcohol and a polyacrylic acid-based water-soluble polymer, Patent Document 2 uses hydroxyethyl cellulose, Patent Document 3 uses a mixture of carboxymethyl cellulose and polyethylene oxide, Patent Document 4 The use of a mixture of water-soluble cellulose and polyvinylpyrrolidone is described in Patent Document 5, a receiving layer formed from a gelatin aqueous solution having a specific pH, Patent Document 6 uses a mixture of gelatin and a surfactant, and Patent Document 7 uses gelatin. As a receiving layer containing a basic latex, Patent Document 8 proposes a receiving layer containing gelatin and an acrylic emulsion.
If the ink jet recording medium described in these patent documents is used, the above-mentioned problem of fading is solved to some extent, but the above-mentioned productivity is insufficient, and there is a problem in the adsorptivity and drying property of ink immediately after printing. In addition, there is a problem that ink absorbability and color developability deteriorate with time during storage of the recording medium. On the other hand, in recent years, pigment inks that take light resistance into consideration have appeared, but the recording medium described in the above-mentioned patent document has a problem in that the recorded image has low abrasion resistance.

JP-A-60-168651 Japanese Patent Application Laid-Open No. 60-262685 JP-A-61-1181679 JP-A 61-193879 JP-A-62-263084 Japanese Patent Laid-Open No. 1-146784 JP-A-8-244336 Japanese Patent Laid-Open No. 10-287036

  As a result of diligent studies to solve the above problems, the present inventors have found that a coating liquid used for producing an inkjet recording medium having at least one ink-receiving layer provided on at least one side of a support, which is constant with gelatin. Use of a coating liquid for an ink jet recording medium comprising a polymer compound (A) which exhibits hydrophilicity in a temperature range below the temperature (temperature sensitive point) and exhibits hydrophobicity in a temperature range above the temperature sensitive point. The present inventors have found that recording using an inkjet recording medium manufactured in this way is effective in solving the above problems, and have led to the present invention.

That is, the present invention is as follows.
1) A coating liquid used for producing an ink jet recording medium having at least one ink-receiving layer provided on at least one side of a support, which exhibits hydrophilicity in a temperature range below gelatin and a certain temperature (temperature sensitive point); A coating liquid for an inkjet recording medium, comprising a polymer compound (A) that exhibits hydrophobicity in a temperature range exceeding a temperature sensitive point.
2) The coating liquid for an ink jet recording medium of the invention of 1), wherein the polymer compound (A) forms a polymer emulsion.
3) The coating liquid for an ink jet recording medium according to any one of 1) or 2), wherein the polymer compound (A) has a carbonyl group.
4) The inkjet recording medium coating liquid according to 3), which contains at least two hydrazine derivatives having a hydrazine group and / or a semicarbazide group.
5) A method for producing an ink jet recording medium in which at least one ink receiving layer is provided on a support, wherein the method for forming at least one ink receiving layer is the method according to any one of 1) to 4). An inkjet recording medium comprising a step of coating a coating liquid for an inkjet recording medium on a support at a temperature exceeding the temperature sensitive point of the polymer compound (A) and then cooling to a temperature below the temperature sensitive point. A method for producing a medium.
6) An ink jet recording medium in which one or more ink receiving layers are provided on a support, and at least one of the coating layers uses the ink jet recording medium coating liquid according to the inventions 1) to 4). An ink jet recording medium characterized by being formed as described above.
7) An inkjet recording medium having one or more ink-receiving layers provided on a support, wherein at least one of the coating layers contains the coating liquid for an inkjet recording medium according to the inventions 1) to 4). An ink jet recording medium comprising a component.

  When the ink jet recording medium coating liquid, the ink jet recording medium manufacturing method, and the ink jet recording medium of the present invention are used, the image quality such as light resistance, water resistance, and abrasion resistance, which has been difficult with the prior art, is at the same time. It becomes possible to produce a recorded matter excellent in storage stability with high productivity.

The present invention will be specifically described below.
The polymer compound (A) of the present invention is a monomer (hereinafter referred to as a main monomer) from which a polymer compound (A) exhibiting temperature responsiveness (hydrophilic-hydrophobic change according to temperature change) can be obtained by homopolymerization. (B))), a copolymerized polymer compound of two or more main monomers (B), and further, the polymer compound (A) reacts with the main monomer (B). Copolymer polymer compound of monomer (hereinafter referred to as submonomer (C)) and main monomer (B), which can be prepared and cannot yield polymer compound (A) exhibiting temperature responsiveness by homopolymerization It is. The main monomer (B) and the submonomer (C) can be used alone or in combination of two or more.
A polymer compound (A) having high temperature responsiveness can be obtained by homopolymerization, but by performing the copolymerization, a polymer compound (A) having a temperature sensitive point different from that of the homopolymer polymer compound (A) Or a polymer compound (A) having a film-forming property different from that of the homopolymer polymer compound (A) is obtained.
By including the polymer compound (A) of the present invention in the ink receiving layer, the inkjet recording medium of the present invention has high gloss on the image surface when printing or recording is performed using the ink composition, High quality images can be obtained.

  The main monomer (B) is an N-alkyl or N-alkylene-substituted (meth) acrylamide derivative (where (meth) acryl is a simple notation of methacryl (or methacryl) or acryl), vinylmethyl Specific examples include N-ethyl (meth) acrylamide, N-isopropyl (meth) acrylamide, N-cyclopropyl (meth) acrylamide, N-ethyl (meth) acrylamide, N, N-diethyl. Acrylamide, N, N-dimethyl (meth) acrylamide, Nn-propyl (meth) acrylamide, N-methyl-Nn-propylacrylamide, N-methyl-N-isopropylacrylamide, N- (meth) acryloylpyrrolidine, N- (meth) acryloylpiperidi N-tetrahydrofurfuryl (meth) acrylamide, N-methoxypropyl (meth) acrylamide, N-ethoxypropyl (meth) acrylamide, N-isopropoxypropyl (meth) acrylamide, N-ethoxyethyl (meth) acrylamide, N- (2,2-dimethoxyethyl) -N-methylacrylamide, N-methoxyethyl (meth) acrylamide, N- (meth) acryloylmorpholine and the like. From the viewpoint of film formability, N-isopropylacrylamide, Nn-propylacrylamide, N, N-diethylacrylamide, and N-acryloylmorpholine are preferable.

Examples of the auxiliary monomer (C) include a lipophilic vinyl compound, a hydrophilic vinyl compound, and an ionic vinyl compound. Specific examples of the lipophilic vinyl compound include methyl (meth) acrylate and ethyl (meth) acrylate. , N-butyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, glycidyl methacrylate, styrene, α-methylstyrene, ethylene, isoprene, butadiene, vinyl acetate, vinyl chloride, and the like. As the hydrophilic vinyl compound, For example, 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, (meth) acrylamide, N-methyl (meth) acrylamide, N-methylol acrylamide, diacetone acrylamide, methylene bisacrylamide, -Methyl-5-vinylpyridine, N-vinyl-2-pyrrolidone, N-acryloylpyrrolidine, acrylonitrile and the like. Examples of ionic vinyl compounds include acrylic acid, methacrylic acid, itaconic acid, fumaric acid, maleic acid. , Crotonic acid, Butenetricarboxylic acid, Monoethyl maleate, Monomethyl maleate, Monoethyl itaconate, Monomethyl itaconate, Monocarboxylic acid group-containing monomer, 2-acrylamido-2-methyl-propanesulfonic acid, styrenesulfonic acid, vinylsulfonic acid And sulfonic acid group-containing monomers such as (meth) acrylsulfonic acid, and amino group-containing monomers such as N, N-dimethylaminoethyl (meth) acrylate and N, N-diethylaminoethyl (meth) acrylate. In particular, methyl (meth) acrylate, n-butyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, styrene, 2-hydroxypropyl (meth) acrylate, acrylamide, methacrylamide, diacetone acrylamide, and methylene bisacrylamide are preferably used. It is done. In addition, from the viewpoint of the film formability of the coating layer obtained using the coating liquid for an inkjet recording medium of the present invention, acrylic acid, methacrylic acid, itaconic acid, fumaric acid, maleic acid, crotonic acid, butenetricarboxylic acid, Carboxylic acid group-containing monomers such as monoethyl maleate, monomethyl maleate, monoethyl itaconate, monomethyl itaconate, 2-acrylamido-2-methyl-propane sulfonic acid, styrene sulfonic acid, vinyl sulfonic acid, (meth) acryl sulfonic acid, etc. It is preferable to use an anion group-containing monomer such as a sulfonic acid group-containing monomer, and it is particularly preferable to use a carboxylic acid group-containing monomer such as acrylic acid, methacrylic acid, itaconic acid, fumaric acid, and maleic acid.

  In ink jet recording using a dye ink, it is preferable for the dye in the ink component to have an anionic group in many cases because the light durability is higher than that of a dye ink having a cationic group. Therefore, it is preferable to add a cationic compound such as a cationic polymer or a cationic particle to the recording medium for the purpose of fixing the dye having an anionic group to the recording medium, and the preparation of the coating liquid is easy. From this viewpoint, it is more preferable that the polymer compound (A) is cationic or nonionic. The cationic polymer compound (A) can be obtained, for example, by including an ethylenically unsaturated monomer having a cationic group as a submonomer (C) used in the polymerization. It is preferable to use an ethylenically unsaturated monomer having a cationic group as the secondary monomer (C). The ethylenically unsaturated monomers having a cationic group can be used alone or in combination of two or more. In particular, the colloidal stability of the resulting polymer emulsion and the viewpoint of the degree of fading that occurs when a printed material printed with an inkjet printer is exposed to sunlight or fluorescent light. From the viewpoint, it is more preferable that the ethylenically unsaturated monomer having a cationic group contains a tertiary amino group and / or a quaternary ammonium base.

The polymer compound (A) containing a tertiary amino group and / or a quaternary ammonium base contains, for example, a main monomer (B) and a tertiary amino group and / or a quaternary ammonium base as a submonomer (C). It is obtained by copolymerizing with a monomer. The main monomer (B) and the submonomer (C) (including monomers containing a tertiary amino group and / or a quaternary ammonium base) can be used alone or in combination of two or more.
The tertiary amino group or quaternary ammonium base-containing monomer is not particularly limited as long as it has a structure containing a tertiary amino group or quaternary ammonium base in the monomer. For example, vinyloxyethyltrimethylammonium chloride, 2 , 3-Dimethyl-1-vinylimidazolinium chloride, trimethyl- (3- (meth) acrylamide-3,3-dimethylpropyl) ammonium chloride, trimethyl- (3-methacrylamidopropyl) ammonium chloride, trimethyl- (3- Acrylamidopropyl) ammonium chloride, N- (1,1-dimethyl-3-dimethylaminopropyl) (meth) acrylamide and its quaternary ammonium salt, trimethyl- (3- (meth) acrylamide) ammonium chloride, -Vinyl-2-methyl-imidazole, 1-vinyl-2-ethyl-imidazole, 1-vinyl-2-phenyl-imidazole, 1-vinyl-2,4,5-trimethyl-imidazole, N, N-dimethylaminopropyl (Meth) acrylate and its quaternary ammonium salt, N, N-dimethylaminoethyl (meth) acrylate and its quaternary ammonium salt, N, N-diethylaminoethyl (meth) acrylate and its quaternary ammonium salt, t-butylamino Ethyl (meth) acrylate and its quaternary ammonium salt, N- (3-dimethylaminopropyl) methacrylamide and its quaternary ammonium salt, N- (3-dimethylaminopropyl) acrylamide and its quaternary ammonium salt, N- ( 3-diethylaminopropyl) methacryla And quaternary ammonium salts thereof, N- (3-diethylaminopropyl) acrylamide and quaternary ammonium salts thereof, o-, m-, p-aminostyrene and quaternary ammonium salts thereof, o-, or m-, or p -Vinylbenzylamine and its quaternary ammonium salt, N- (vinylbenzyl) pyrrolidone, N- (vinylbenzyl) piperidine, N-vinylimidazole and its quaternary ammonium salt, 2-methyl-1-vinylimidazole and its quaternary Ammonium salt, N-
Vinylpyrrolidone and its quaternary ammonium salt, N, N′-divinylethyleneurea and its quaternary ammonium salt, α-, or β-vinylpyridine and its quaternary ammonium salt, α-, or β-vinylpiperidine and its 4 Examples include quaternary ammonium salts, 2-, or 4-vinylquinoline and quaternary ammonium salts thereof. In particular, a methyl chloride quaternary compound of N, N-dimethylaminopropyl methacrylate, N, N-dimethylaminoethyl methacrylate, N, N-dimethylaminopropyl (meth) acrylamide is preferably used. Furthermore, it is more preferable to use a quaternary ammonium group-containing monomer rather than a tertiary amino group-containing monomer from the viewpoint of the degree of fading that occurs when the printed material is exposed to sunlight or fluorescent light. Further, when both the tertiary amino group and / or quaternary ammonium base-containing monomer and the anion group-containing monomer are contained, the preparation of the coating liquid described above and the coating for the ink jet recording medium of the present invention are carried out. It is preferable from the viewpoints of both film formability of the coating layer obtained using the liquid.

The copolymerization ratio of the main monomer (B) and the submonomer (C) is within a range in which the obtained copolymer polymer compound exhibits temperature responsiveness in which hydrophilicity and hydrophobicity reversibly change at a certain temperature as a boundary. It is decided in. That is, when the proportion of the submonomer (C) is too large, the copolymer polymer compound obtained does not exhibit the temperature responsiveness.
That is, the copolymerization ratio of the main monomer (B) and the submonomer (C) depends on the combination of the monomer types used, but the ratio of the submonomer (C) in the polymer compound (A) to be generated is 50% by mass or less. Is preferred. More preferably, it is 30 mass% or less. Moreover, 0.01 mass% or more is preferable in order for the addition effect of a submonomer (C) to be expressed better.
The use of a polymer compound containing a carbonyl group as the polymer compound (A) used in the present invention makes it possible to impart water resistance and abrasion resistance to the ink receiving layer by crosslinking with a hydrazine derivative described later. Furthermore, it is particularly preferable since the water resistance and abrasion resistance of the recorded matter (image) to be obtained are greatly improved.
The polymer compound (A) containing a carbonyl group is obtained, for example, by using a monomer containing a carbonyl group as a submonomer (C) and copolymerizing it with the main monomer (B) and another submonomer (C). The high molecular compound which can be mentioned is mentioned.
The carbonyl group-containing monomer is not particularly limited as long as the monomer has a structure containing a keto group or an aldo group. For example, acrolein, diacetone acrylamide, diacetone methacrylamide, formyl styrene, vinyl methyl ketone, vinyl Examples include ethyl ketone, vinyl isobutyl ketone, acryloxyalkyl propanals, methacryloxyalkyl propanals, diacetone acrylate, diacetone methacrylate, acetonitrile acrylate, 2-hydroxypropyl acrylate acetyl acetate, butanediol acrylate acetyl acetate, etc. .

The content of the carbonyl group-containing monomer unit in all monomer units of the polymer compound (A) is not particularly limited, but is preferably 0.01 to 30% by mass, more preferably from the viewpoint of imparting water resistance and abrasion resistance. It is 0.1-20 mass%.
When the polymer compound (A) of the present invention contains a carbonyl group, the use of a hydrazine derivative having at least two hydrazine groups and / or semicarbazide groups as a crosslinking agent in the ink receiving layer It is preferable from the viewpoint of water resistance and abrasion resistance.
The hydrazine derivative does not proceed with the carbonyl group in the presence of water, but is known to cause a dehydration reaction upon drying and to form a bond. After coating the ink receiving layer, the ink receiving layer is dried. As a result, a molecular structure in which the carbonyl group portion is cross-linked by the hydrazine derivative is formed, and the swelling of the ink receiving layer can be suppressed and water resistance can be exhibited. The hydrazine derivative is not particularly limited as long as it is a compound having at least two hydrazine groups and / or semicarbazide groups. Among them, examples of the compound having a hydrazine group include carbohydrazide, isophthalic acid dihydrazide, and malonic acid. Dihydrazide, succinic acid dihydrazide, glutaric acid dihydrazide, adipic acid dihydrazide, sebacic acid dihydrazide, maleic acid dihydrazide, fumaric acid dihydrazide, itaconic acid dihydrazide, polyacrylic acid hydrazide, ethylene-1,2-dihydrazine, propylene-1,3-propylene Examples of the compound having a semicarbazide group include dihydrazine, butylene-1,4-dihydrazine, and hydrated hydrazine. For example, the compound having a semicarbazide group is obtained by reacting a polyisocyanate compound with the hydrazine compound. Product that is exemplified. When a compound having a semicarbazide group is used as the hydrazine derivative, the water resistance of the ink receiving layer is higher because the crosslinked structure of the carbonyl group and the semicarbazide group formed after application of the ink receiving layer is not easily hydrolyzed by water. preferable.
Specific examples of the compound having a semicarbazide group include, for example, a semicarbazide derivative represented by the following formula (1), a bissemicarbazide represented by the following formula (2), and the like.

（式中、Ｒ¹ は、直鎖状または分岐状の炭素数２〜２０のアルキレンジイソシアネート、置換基を有しても有さなくても良い炭素数５〜２５のシクロアルキレンジイソシアネート、置換基を有しても有さなくても良い炭素数６〜２０のアリーレンジイソシアネート、及び置換基を有しても有さなくても良い炭素数８〜２０のアラルキレンジイソシアネートからなる群から選ばれる少なくとも１種のジイソシアネートの３量体〜２０量体オリゴマーに由来する、末端イソシアネート基を有さないポリイソシアネート残基、もしくはＲ¹ は炭素数１〜８のイソシアナトアルキル基で置換されている炭素数２〜２０のアルキレンジイソシアネートに由来する、末端イソシアネート基を有さないトリイソシアネート残基を表す。Ｒ² は、水素原子または炭素数１〜２０のアルキル基を表す。Ｒ³ は、直鎖状または分岐状の炭素数１〜２０のアルキレン基、炭素数５〜２０のシクロアルキレン基、もしくは置換基を有しても有さなくても良い炭素数６〜１０のアリーレン基を表す。ｎは、０または１を表す。ｌ及びｍは、各々０または正の整数を表す。ただし、２０≧（ｌ＋ｍ）≧３である。）

(In the formula, R ¹ represents a linear or branched alkylene diisocyanate having 2 to 20 carbon atoms, a cycloalkylene diisocyanate having 5 to 25 carbon atoms which may or may not have a substituent, and a substituent. At least 1 selected from the group consisting of arylene diisocyanates having 6 to 20 carbon atoms that may or may not have and those having 8 to 20 carbon atoms that may or may not have a substituent. A polyisocyanate residue having no terminal isocyanate group, derived from a trimer to a 20-mer oligomer of a kind of diisocyanate, or R ¹ is substituted with an isocyanatoalkyl group having 1 to 8 carbon atoms. from 20 alkylene diisocyanate, .R ² representing the triisocyanate residue without the terminal isocyanate groups is a hydrogen atom or Represents an alkyl group of prime 1-20 .R ³ is no have a linear or branched alkylene group having 1 to 20 carbon atoms, cycloalkylene group having 5 to 20 carbon atoms or a substituent, It may be an arylene group having 6 to 10 carbon atoms, n represents 0 or 1. l and m each represents 0 or a positive integer, provided that 20 ≧ (l + m) ≧ 3. )

（式中、Ｒ⁵ は、直鎖状または分岐状の炭素数２〜２０の２価の脂肪族残基、炭素数６〜２５の２価の脂環族残基、置換基を有しても有さなくても良い炭素数６〜２５の２価の芳香族残基、及び置換基を有しても有さなくても良い炭素数６〜２５の２価の芳香脂環族残基を表す。Ｒ⁴ は、水素原子または炭素数１〜２０のアルキル基を表す。）
上記ポリセミカルバジド化合物の中で、前記式（１）で表されるセミカルバジド誘導体は、多官能であり、架橋能力が高いことから非常に好ましい。

(In the formula, R ⁵ has a linear or branched divalent aliphatic residue having 2 to 20 carbon atoms, a divalent alicyclic residue having 6 to 25 carbon atoms, and a substituent. And a divalent aromatic residue having 6 to 25 carbon atoms that may or may not have, and a divalent aromatic alicyclic residue having 6 to 25 carbon atoms that may or may not have a substituent. R ⁴ represents a hydrogen atom or an alkyl group having 1 to 20 carbon atoms.)
Among the polysemicarbazide compounds, the semicarbazide derivative represented by the formula (1) is very preferable because it is polyfunctional and has high crosslinking ability.

In the present invention, the content of the hydrazine derivative is not particularly limited, but the ratio of the carbonyl group to the hydrazine group in the hydrazine derivative in the ink receiving layer is 0.001 to 10 in terms of (carbonyl group) / (hydrazine group) molar ratio. It is preferable that it is the range of these.
In the present invention, the “temperature sensitive point” of the polymer compound (A) is a temperature at which the hydrophilicity-hydrophobicity changes according to a temperature change, and the “temperature responsiveness” refers to a temperature change. This means a property showing a change in hydrophilicity-hydrophobicity. In the present invention, the term “hydrophilic” means that the polymer compound (A) in a system in which the polymer compound (A) and water coexist is more stable in a state compatible with water than in a phase separated state. In the system where the polymer compound (A) and water coexist, the polymer compound (A) is in a state in which the polymer compound (A) is phase-separated from water than in a state in which the polymer compound (A) is in solution. Means stable. The change in hydrophilicity-hydrophobicity is, for example, an abrupt viscosity change accompanying a temperature change in a system in which the polymer compound (A) and water coexist, or transparency in a system in which the polymer compound (A) and water coexist. It appears as a sudden change in the solubility of the polymer compound (A) in water. That is, the viscosity when the temperature of the system in which the polymer compound (A) and water coexist is gradually lowered from the temperature range where the polymer compound (A) exhibits hydrophobicity (temperature exceeding the temperature sensitive point). The polymer compound (A) obtained as a transition point where the temperature-viscosity curve obtained by measurement changes rapidly or in a temperature range where the polymer compound (A) exhibits hydrophobicity (temperature exceeding the temperature sensitive point) The temperature sensitive point of the polymer compound (A) can be determined as the temperature at which the dispersion begins to become transparent or gel when the aqueous dispersion is gradually cooled.

Although the temperature sensitive point of the polymer compound (A) used in the present invention is not particularly limited, it is preferably 5 to 90 ° C. from the viewpoint of coating workability and film forming property, and the temperature at which the viscosity of the gelatin aqueous solution increases is also considered. If it is, 15-50 degreeC is still more preferable, and 20-40 degreeC is the most preferable.
The glass transition point of the polymer compound (A) used in the present invention is not particularly limited, but is preferably −50 to 150 ° C. from the viewpoints of film formability and flexibility of the obtained recording medium, and the obtained inkjet recording medium When emphasizing ink absorptivity, 30 to 130 ° C. is preferable, and when emphasizing flexibility of the obtained ink jet recording medium, −50 to 30 ° C. is preferable.
In producing the polymer compound (A) of the present invention, it is preferable to carry out the polymerization reaction in a temperature range exceeding the temperature sensitive point of the polymer compound (A). Since the polymer compound (A) exhibits hydrophobicity and forms an emulsion in the temperature region, the polymer compound (A) of the present invention can be obtained by using a widely known polymer emulsion production technique in the temperature region. ) Is obtained. Specifically, the surfactant is dissolved in water, the copolymerization monomer component such as the main monomer (B) and the submonomer (C) is added and emulsified, and the radical polymerization initiator is added and emulsified by a reaction by batch charging. In addition to the method of performing polymerization, there may be mentioned a method of supplying the above-mentioned copolymerization component or radical polymerization initiator to the reaction system by a method such as continuous dropping or divided addition.
In producing a polymer emulsion containing the polymer compound (A) used in the present invention, it is preferable to use a surfactant.
The polymer emulsion containing the polymer compound (A) of the present invention may be any of anionic, cationic, nonionic and amphoteric.

  When the polymer emulsion containing the polymer compound (A) is anionic, an anionic surfactant and / or a nonionic surfactant is used. For example, fatty acid soap, alkyl sulfonate, alkyl sulfosuccinate, polyoxyethylene alkyl sulfate, polyoxyethylene alkyl aryl sulfate, p-styrene sulfonate, alkyl naphthalene sulfonate, naphthalene sulfonate, formalin heavy Condensate, condensate of higher fatty acid and amino acid, dialkylsulfosuccinate ester salt, naphthenate, etc., alkyl ether carboxylate, acylated peptide, α-olefin sulfonate, N-acylmethyl taurate, alkyl ether sulfate, Anionic surfactants such as secondary higher alcohol ethoxy sulfates, polyoxyethylene alkylphenyl ether sulfates, monoglyculates, alkyl ether phosphate salts, alkyl phosphate salts and the like can be mentioned. Examples of the nonionic surfactant include polyoxyethylene alkyl aryl ether, polyoxyethylene alkyl phenyl ether, polyoxyethylene sorbitan fatty acid ester, oxyethylene oxypropylene block copolymer, polyglycerin fatty acid ester, and the like.

When the polymer emulsion containing the polymer compound (A) is cationic, a cationic surfactant and / or a nonionic surfactant is used. For example, examples of the cationic surfactant include laurylamine hydrochloride, alkylbenzyldimethylammonium chloride, lauryltrimethylammonium chloride, alkylammonium hydroxide, and polyoxyethylene alkylamine. Nonionic surfactants include Examples include polyoxyethylene alkyl aryl ether, polyoxyethylene alkyl phenyl ether, polyoxyethylene sorbitan fatty acid ester, oxyethylene oxypropylene block copolymer, polyglycerin fatty acid ester and the like.
When the polymer emulsion containing the polymer compound (A) is nonionic, a nonionic surfactant is used. Examples of the nonionic surfactant include polyoxyethylene alkyl aryl ether, polyoxyethylene alkyl phenyl ether, polyoxyethylene sorbitan fatty acid ester, oxyethylene oxypropylene block copolymer, polyglycerin fatty acid ester, and the like.
When the polymer emulsion containing the polymer compound (A) is amphoteric, it is preferable to use an amphoteric surfactant from the viewpoint of stability against changes in pH of the polymer emulsion. When the polymer emulsion is cationic, a cationic surfactant can be used. When the polymer emulsion is anionic in the coating liquid of the present invention, an anionic surfactant can be used. Can be used. Examples of the amphoteric surfactant include carboxybetaine type, aminocarboxylate, lecithin and the like.
The amount of these surfactants to be used is preferably 0.05 to 30 parts by mass, more preferably 0. 0 to 30 parts by mass with respect to 100 parts by mass of the resin solid content of the polymer emulsion containing the polymer compound (A). 5 to 10 parts by mass.

In this invention, the said surfactant can also be used individually by 1 type, and the 2 or more types can also be used together.
The average particle diameter when the polymer compound (A) forms a polymer emulsion is not particularly limited, but is preferably 200 nm or less from the viewpoint of adhesive strength, and preferably 10 nm or more from the viewpoint of productivity of the polymer emulsion. .
In the present invention, the content of the polymer compound (A) in the ink receiving layer is not particularly limited, but it is preferably 5 to 400 parts by mass, and preferably 5 to 100 parts by mass with respect to 100 parts by mass of gelatin. More preferably. That is, 5 parts by mass or more is preferable from the viewpoint of productivity of the ink jet recording medium described below and the viewpoint of storage stability of the ink jet recording medium, and 400 parts by weight or less is preferable from the viewpoint of ink absorbability.

  As the gelatin used in the present invention, any gelatin can be used as long as it is made from animal collagen. For example, gelatin made from collagen made from pig skin, cow skin, or cow bone is preferred. Further, the type of gelatin is not particularly limited. For example, lime-processed gelatin, acid-processed gelatin, and gelatin derivatives (for example, gelatin derivatives described in JP-B Nos. 38-4854 and 39-5514) can be used alone or They can be used in combination.

In the present invention, the solvent used in the coating liquid for producing an inkjet recording medium is not particularly limited, but a water-soluble solvent such as alcohol, ketone and ester, and / or water is preferably used. Furthermore, a pigment dispersant, a thickener, a flow regulator, a defoaming agent, a defoaming agent, a release agent, a foaming agent, a colorant, and the like can be blended in the coating liquid as necessary.
In the present invention, the coating liquid for producing an inkjet recording medium preferably contains a water-soluble polymer from the viewpoint of ink absorbability of the ink receiving layer. Examples of the water-soluble polymer include polyvinyl formal such as polyvinyl alcohol, polyvinyl pyrrolidone, polyvinyl pyridinium halide, various modified polyvinyl alcohols and derivatives thereof (for example, JP-A-60-145879, JP-A-60-220750, JP-A-61-2). 143177, 61-235182, 61-235183, 61-237681, 61-26189), polyacrylamide, polydimethylacrylamide, polydimethylaminoacrylate, sodium polyacrylate Polymers containing acrylic groups such as acrylic acid / methacrylic acid copolymer salt, poly (sodium methacrylate), vinyl acrylate / vinyl alcohol copolymer salt (for example, JP-A-60-168651, 62-9988, etc.) ), Natural polymers such as starch, oxidized starch, carboxyl starch, dialdehyde starch, cationized starch, dextrin, sodium alginate, gum arabic, casein, pullulan, dextran, methylcellulose, ethylcellulose, carboxymethylcellulose, hydroxypropylcellulose, and their derivatives (For example, as described in JP-A Nos. 59-174382, 60-262585, 61-143177, 61-181679, 61-193879, 61-287882, etc.) Polyethylene glycol, polypropylene glycol, polyvinyl ether, polyglycerin, maleic acid alkyl vinyl ether copolymer, maleic acid-N-vinyl pyrrole copolymer, styrene-maleic anhydride copolymer, Mention may be made of synthetic polymers such as triethylene imine (for example, JP-61- 32787, JP same 61- 237680, JP-the 61- 277483 Patent described in Japanese or the like) and the like. Among these water-soluble polymers, from the viewpoint of ink acceptability and dot reproducibility, for example, at least selected from polyvinyl pyrrolidone, polyvinyl pyrrolidone derivatives, polyvinyl alcohol, polyvinyl alcohol derivatives, polyacrylamide, polyacrylamide derivatives, and polyacrylic acid. One synthetic polymer is preferably used in combination, more preferably polyacrylamide, polyvinyl pyrrolidone, and polyvinyl alcohol, and still more preferably polyvinyl pyrrolidone and polyvinyl alcohol. These polymers preferably have an average molecular weight of 10,000 or more, more preferably 100,000 or more from the viewpoint of surface stickiness.

  In the present invention, the above-mentioned natural polymers such as carboxymethyl cellulose and hydroxypropyl cellulose or derivatives thereof, or water-soluble cellulose derivatives are also preferably used in combination for the purpose of improving ink receptivity, dot reproducibility, and prevention of stickiness of the printed portion. . Examples of the water-soluble cellulose derivative used in combination include water-soluble cellulose derivatives such as methyl cellulose, carboxymethyl cellulose, hydroxymethyl cellulose, hydroxyethyl cellulose, and hydroxypropyl cellulose. Among these water-soluble cellulose derivatives, at least one water-soluble cellulose derivative selected from carboxymethyl cellulose, hydroxyethyl cellulose, and methyl cellulose may be used in combination from the viewpoint of ink acceptability, dot reproducibility, and prevention of stickiness in the printed portion. preferable.

The ink jet recording medium of the present invention is excellent in the sharpness, resolution and uniformity of an image recorded using a dye ink, the ink adsorbing property and the drying property immediately after printing, and when the pigment ink is used. It was found that printability (image sharpness, image abrasion resistance, etc.) is high. The reason for this is not clear, but is presumed to be due to the influence of hydrogen bonding groups contained in the polymer compound (A).
Furthermore, it has also been found that there is little quality degradation when the inkjet recording medium of the present invention is stored for a long period of time. The reason for this is not clear, but it is presumed that the presence of the polymer compound (A) inhibits the phenomenon in which the ink absorbability decreases due to the crystallization of gelatin molecules over time.
In the present invention, a surfactant can be added to the ink receiving layer from the viewpoint of improving dot reproducibility. The surfactant used may be any of anionic, cationic, nonionic, and betaine types, and may be a low-molecular or high-molecular one. One or more surfactants can be used, and the addition amount of the surfactant is preferably 0.001 to 5 parts by mass, more preferably 0.01 to 3 parts by mass with respect to 100 parts by mass of the polymer compound (A). Part by mass.

In the present invention, the ink receiving layer can be hardened with a suitable hardener for the purpose of improving water resistance and dot reproducibility. Specific examples of the hardener 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, for example, a compound having a reactive halogen as described in US Pat. No. 3,288,775, a divinyl sulfone, for example, a compound having a reactive olefin as described in US Pat. No. 3,635,718, For example, N-methylol compounds as described in US Pat. No. 2,732,316, for example, isocyanates as described in US Pat. No. 3,103,437, such as those described in US Pat. Nos. 3,017,280 and 2983611 Aziridine compounds such as US Patent No. Carbodiimide compounds as described in US Pat. No. 100704, for example, epoxy compounds as described in US Pat. No. 3,091,537, halogen carboxaldehydes such as mucochloric acid, dioxane derivatives such as dihydroxydioxane, chromium alum, potassium alum Examples include inorganic hardeners such as zirconium and zirconium sulfate, and these can be used alone or in combination of two or more. The addition amount of the hardener varies depending on the type of the polymer compound constituting the ink receiving layer, but is 0.01 to 10 parts by mass with respect to 100 parts by mass of the water-soluble polymer and the polymer compound (A). Preferably, it is 0.1-5 mass parts.

In the present invention, in addition to the above-mentioned surfactants and hardeners, the ink receiving layer contains inorganic pigments, colored dyes, colored pigments, ink dye fixing agents, ultraviolet absorbers, antioxidants, pigment dispersants. Various known additives such as an antifoaming agent, a leveling agent, an antiseptic, a fluorescent brightening agent, a viscosity stabilizer, and a pH adjusting agent can also be added. When an inkjet recording medium is produced using the coating liquid for inkjet recording medium of the present invention, the coating liquid is heated or maintained at a temperature exceeding the temperature sensitive point of the polymer compound (A) on the support. It is preferable to include a step of cooling the coated layer to a temperature not higher than the temperature sensitive point after coating. The coating liquid for an ink jet recording medium of the present invention has a relatively low viscosity at a temperature exceeding the temperature sensitive point of the polymer compound (A) and is high at a temperature below the temperature sensitive point of the polymer compound (A). A uniform and smooth coating film obtained by applying a relatively low-viscosity coating liquid that has a viscosity-increasing property is maintained in a homogeneous and smooth state by thickening (gelling) by cooling. It is possible to obtain a good quality ink receiving layer.
When the coating liquid for inkjet recording medium of the present invention is used, the viscosity is significantly increased by cooling (good setting property), and the viscosity is less likely to be lowered (difficult to return to setting) even in the subsequent drying process by hot air. Thus, an ink jet recording medium can be manufactured with extremely high production efficiency.

As a coating method for the inkjet recording medium coating liquid in the present invention, a commonly used coating method (for example, slide lip method, curtain method, extrusion method, air knife method, roll coating method, rod bar coating method, etc.) However, the slide lip method and the curtain method are preferable in that a multilayer ink receiving layer can be provided at a time. The ink receiving layer is provided on at least one side of the support, but may be provided on both sides of the support for the purpose of preventing curling. As means for cooling the coating layer, known means such as a cold air blower, a blower, and a refrigerator can be used. A cold air machine is preferably used, and the temperature of the cold air varies depending on the temperature sensitive point of the polymer emulsion containing the polymer compound (A) of the present invention, and is preferably a temperature below the temperature sensitive point, more than the temperature sensitive point. A temperature lower by 5 ° C. or more is more preferable, and a temperature lower by 10 ° C. or more than the temperature sensitive point is more preferable.
As means for drying the coating layer, known drying means such as a hot air dryer, a steam heating dryer, a far-infrared dryer and the like can be used. A hot air dryer is preferably used, and examples thereof include a drum dryer, an air cap dryer, an air foil dryer, an air conditioner dryer, and combinations thereof. The drying temperature varies depending on the type of dryer, but the temperature inside the dryer is 50 to 200 ° C, preferably 70 to 150 ° C.
Recording medium of the invention thus produced is coated amount of the ink receiving layer, it is preferably 5 to 50 g / m ² in terms of solid content, a 10 to 40 g / m ² Further preferred. When the coating amount is less than 5 g / m ² , the effect is small in terms of the coloring property of the dye as compared with the case where the ink receiving layer is not provided, and when it exceeds 50 g / m ² , the ink receiving layer is powdered off. There is a fear. In addition, as thickness of the whole coating layer, 5-50 micrometers is preferable and 10-40 micrometers is still more preferable.

As the support used in the present invention, a transparent support or an opaque support can be used. As the transparent support, any conventionally known one can be used, for example, a polyester resin, diacetate resin, triacetate resin, acrylic resin, polycarbonate resin, polyvinyl chloride, polyimide resin, cellophane, celluloid film or plate, and A glass plate etc. are mentioned. Such a transparent support preferably has a thickness of about 10 to 200 μm.
As the opaque support, any conventionally known materials such as paper, coated paper, synthetic paper, resin-coated paper, pigmented opaque film, foamed film and the like can be used. Synthetic paper, resin-coated paper, and various films are more preferable in terms of gloss and smoothness, but resin-coated paper similar to a photographic support is more preferable in terms of touch and luxury.

The base paper constituting the resin-coated paper preferably used in the present invention is not particularly limited, and generally used paper can be used. More preferably, however, a smooth base paper used for a photographic support, for example. Is preferred. As the pulp constituting the base paper, natural pulp, recycled pulp, synthetic pulp or the like is used alone or in combination of two or more. This base paper is blended with additives such as sizing agent, paper strength enhancer, filler, antistatic agent, fluorescent whitening agent, and dye generally used in papermaking. Further, a surface sizing agent, surface paper strengthening agent, fluorescent brightening agent, antistatic agent, dye, anchor agent and the like may be applied on the surface.
In addition, the thickness of the base paper is not particularly limited, but preferably has a good surface smoothness such as a paper that is compressed by applying a pressure during or after paper making using a calendar or the like, and has a basis weight of 30 to 250 g / m 2 is preferred.
As the resin of the resin-coated paper, a thermoplastic resin such as a polyolefin resin, or a resin that is cured by heat, ultraviolet rays, an electron beam, or the like can be used. Examples of polyolefin resins include homopolymers of olefins such as low density polyethylene, high density polyethylene, polypropylene, polybutene, and polypentene, or copolymers composed of two or more olefins such as ethylene-propylene copolymer, and mixtures thereof. Those having various densities and melt viscosity indices (melt index) can be used alone or as a mixture thereof.
In addition, 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, aluminum stearate, stearin Fatty acid metal salts such as magnesium acid, antioxidants such as Irganox 1010 and Irganox 1076, blue pigments and dyes such as cobalt blue, ultramarine blue, cecilian blue and phthalocyanine blue, magenta such as cobalt violet, fast violet and manganese purple It is preferable to add various additives such as pigments and dyes, fluorescent brighteners and ultraviolet absorbers in appropriate combinations.

The resin-coated paper which is a support preferably used in the present invention is produced by a so-called extrusion coating method in which, in the case of a thermoplastic resin such as a polyolefin resin on a traveling base paper, a heat-melted resin is cast, and both sides thereof are produced. Is covered with resin. In addition, in the case of a resin that is cured by heat, ultraviolet light, electron beam, etc., after applying the resin with a commonly used coater such as a gravure coater, blade coater, etc., the resin is cured by hot air drying, ultraviolet light or electron beam irradiation, etc. Cover. Moreover, it is preferable to subject the base paper to an activation treatment such as corona discharge treatment or flame treatment before coating the resin on the base paper. The surface (surface) on which the ink receiving layer of the support is applied has a glossy surface, a matte surface, etc., depending on the application, and the glossy surface is particularly preferentially used. It is not necessary to coat the back surface with a resin, but it is preferable to coat the resin from the viewpoint of curling prevention. The back surface is usually a matte surface, and an activation treatment such as corona discharge treatment or flame treatment can be applied to the front surface or both the front and back surfaces as necessary. Moreover, there is no restriction | limiting in particular as thickness of a coating resin layer, Generally, it coats on the surface or both surfaces by the thickness of 5-50 micrometers.
Various back coat layers can be coated on the support in the present invention for antistatic properties, transport properties, anticurling properties, and the like. The backcoat layer can contain an appropriate combination of inorganic antistatic agent, organic antistatic agent, latex, curing agent, pigment, surfactant and the like.

EXAMPLES Hereinafter, although this invention is demonstrated based on an Example, this invention is not restrict | limited by these. In the following examples and comparative examples, “parts” and “%” represent “parts by mass” and “mass%”.
The number average particle size by the dynamic light scattering method was measured using ELS-800 manufactured by Otsuka Electronics Co., Ltd.
The temperature sensitive point of the polymer compound (A) that formed the polymer emulsion of the present invention is the solid content concentration of the polymer compound (A) that formed the polymer emulsion in an aqueous solvent while maintaining the temperature above the polymerization temperature. Was prepared to 5 mass%, the viscosity of the polymer compound (A) forming the polymer emulsion was measured using a B-type viscometer while gradually decreasing, and a temperature-viscosity curve was drawn. It was determined by measuring the transition point at which the viscosity of the polymer compound (A) forming the polymer emulsion changes rapidly. In the examples and comparative examples, each of the dye ink color developability, recording medium storage stability, pigment ink color developability, pigment ink fixability, and recording medium water resistance was evaluated according to the following criteria. In addition, in each evaluation of dye ink color developability and recording medium storage stability, each evaluation of pigment ink color developability and pigment ink fixability is performed using an ink jet printer (PM900C, manufactured by Seiko Epson Corporation) using a commercially available dye ink. Was performed using an inkjet printer (PX900G, manufactured by Seiko Epson Corporation) using a commercially available pigment ink.

(Evaluation of dye ink color development)
The color development of the image portion of the recorded matter 30 minutes after printing was sensoryly evaluated by visual observation, and the following determinations were made.
○: Clear color development and high color density.
Δ: The color density is high although there is a feeling of slight wrinkles.
X: Feels like wrinkles and color density is low.
(Evaluation of recording medium storage stability)
After the preparation, an ink jet recording medium which is placed in a thermo-hygrostat and alternately repeats an environment of 25 ° C. and 80% RH and an environment of 25 ° C. and 45% every 24 hours, and this is performed continuously for 4 weeks. The color development of the image portion of the recorded matter 30 minutes after printing in the same manner on both of the inkjet recording media produced in the same manner and kept in a constant temperature and humidity chamber for 24 hours in an environment of 25 ° C. and 45% The image quality was sensuously evaluated visually and the following determinations were made.
○: No change is observed at all.
Δ: A slight change is observed.
X: A clear change is recognized.
(Evaluation of pigment ink color development)
The color development of the image portion of the recorded matter 30 minutes after printing was sensoryly evaluated by visual observation, and the following determinations were made.
○: Clear color development and high color density.
Δ: The color density is high although there is a feeling of slight wrinkles.
X: Feels like wrinkles and color density is low.
(Evaluation of fixability of pigment ink)
The image portion of the recorded matter 30 minutes after printing was rubbed strongly with a finger and evaluated according to the following criteria.
○: No stain is generated Δ: Slightly dirty ×: Dirty (evaluation of recording medium water resistance)
The prepared inkjet recording medium was immersed in water at 20 ° C. for 10 minutes, and then the surface of the recording medium was rubbed with a finger, the water resistance was evaluated functionally, and the following determinations were made.
○: The change is not small and the strength is sufficiently strong.
Δ: Slight swelling occurs, but peeling of the ink receiving layer does not occur.
X: The ink receiving layer peels off when rubbed with a finger.

(Preparation Example 1)
In a reaction vessel equipped with a stirrer, a reflux condenser, a dropping tank, and a thermometer, 360 parts of water was added to bring the inside of the reaction vessel to 80 ° C. Next, 25 parts of 25% aqueous solution of “Coatamine 86W” (manufactured by Kao Corporation, cationic surfactant: trade name), “Emulgen 1135S-70” (manufactured by Kao Corporation, nonionic surfactant: commodity In addition, 7.5 parts of a 70% aqueous solution of No. 1) and 4 parts of a 70% aqueous solution of N, N-dimethylaminopropylacrylamide methyl chloride quaternary salt were added to the reactor. Further, 8 parts of a 5% aqueous solution of 2,2′-azobis (2-methylpropionamidine) dibasic acid salt was charged into the reactor, and after 5 minutes, 9 parts of methyl methacrylate, 9 parts of butyl acrylate, A solution obtained by mixing 9 parts of styrene, 2 parts of diacetone acrylamide and 2 parts of 2-hydroxyethyl methacrylate was continuously added into the reactor over 30 minutes. The addition was performed while keeping the inside of the reaction vessel at 80 ° C. The number average particle size of the emulsion at this stage was 11 nm. Subsequently, 220 parts of N-isopropylacrylamide, 10 parts of diacetone acrylamide, 0.5 parts of methylenebisacrylamide, 5 parts of 70% aqueous solution of methyl quaternary salt of N, N-dimethylaminopropylacrylamide methyl chloride, “Cotamine 86W 14 parts of a 25% aqueous solution and 11 parts of a 5% aqueous solution of 2,2′-azobis (2-methylpropionamidine) dibasic acid and 70 parts of methyl methacrylate were added to the reaction vessel. Start and finish addition over 4 hours. The liquid temperature in the reaction vessel was kept at 80 ° C. during the addition and for 1 hour after the addition was completed, and then cooled to 50 ° C., and 1000 parts of a 60% aqueous solution of ethanol was gradually added to the reaction vessel. After completion of the addition of the ethanol aqueous solution, the polymer compound 1 having a resin solid content of 11% and a polymer emulsion having a number average particle size of 80 nm was obtained by cooling to room temperature. The temperature point was measured and found to be 19 ° C.

(Preparation Example 2)
In a reaction vessel equipped with a stirrer, a reflux condenser, a dropping tank, and a thermometer, 200 parts of water was added to bring the inside of the reaction vessel to 80 ° C. Next, 20 parts of a 25% aqueous solution of “Coatamine 86W” (manufactured by Kao Corporation, cationic surfactant: trade name), “Emulgen 1135S-70” (manufactured by Kao Corporation, nonionic surfactant: commodity Name) 10% 70% aqueous solution, "Blemmer QA" (Nippon Yushi Co., Ltd., cationic reactive surfactant: product name) 15% 25% aqueous solution and N, N-dimethylaminopropylacrylamide methyl chloride 4 Two parts of a 70% aqueous salt solution were added into the reactor. Further, 15 parts of a 5% aqueous solution of 2,2′-azobis (2-methylpropionamidine) dibasic acid salt was charged into the reactor, and after 5 minutes, 15 parts of methyl methacrylate, 20 parts of butyl acrylate, A liquid obtained by mixing 10 parts of styrene and 2 parts of diacetone acrylamide was continuously added to the reactor over 1 hour. The addition was performed while keeping the inside of the reaction vessel at 80 ° C. The number average particle size of the emulsion at this stage was 40 nm. Subsequently, 380 parts of water, 60 parts of N-isopropylacrylamide, 4 parts of diacetone acrylamide, 5 parts of 2-hydroxyethyl methacrylate, “Blenmer QA” (manufactured by NOF Corporation, cationic reactive surfactant: trade name) ) And a solution of 11 parts of a 5% aqueous solution of 2,2′-azobis (2-methylpropionamidine) dibasic acid and 30 parts of methyl methacrylate were added to the reaction vessel. Start and finish addition over 4 hours. The liquid temperature in the reaction vessel was kept at 80 ° C. during the addition and after completion of the addition for 1 hour, and then cooled to 50 ° C., and 500 parts of a 60% aqueous solution of ethanol was gradually added into the reaction vessel. After completion of the addition of the aqueous ethanol solution, the polymer compound 2 having a polymer emulsion having a resin solid content of 11% and a number average particle size of 80 nm was obtained by cooling to room temperature. The temperature point was measured and found to be 14 ° C.

(Preparation Example 3)
In a reaction vessel equipped with a stirrer, reflux condenser, dropping tank and thermometer, 600 parts of water and 40 parts of 28% aqueous solution of “Cotamine 86W”, 70% aqueous solution of N, N-dimethylaminopropylacrylamide methyl chloride quaternary salt 6 parts were charged and the inside of the reaction vessel was brought to 80 ° C. Next, 4 parts of diacetone acrylamide, 128 parts of styrene, 80 parts of methyl methacrylate, 66 parts of butyl methacrylate, and 100 parts of water, 9 parts of a 28% aqueous solution of “Cotamine 86W”, “ 1 part of 70% aqueous solution of "Emulgen 1135S-70", 45 parts of 5% aqueous solution of 2,2'-azobis (2-methylpropionamidine) dibasic acid, 6 parts of 70% aqueous solution of aminoethyl methacrylate methyl chloride quaternary salt The additive solution (2) in which was dissolved was added to the reaction vessel from the dropping tank over 4 hours. The temperature in the reaction vessel was kept at 80 ° C. during the addition and for another hour after the addition was completed, and then cooled to room temperature. A polymer compound 3 having a polymer emulsion having a resin solid content of 30% and a number average particle size of 40 nm was obtained. Attempts were made to measure the temperature sensitive point, but no change that was judged to be a temperature sensitive point occurred.
(Preparation Example 4)
168 parts of hexamethylene diisocyanate and 1.5 parts of water as a burette agent are dissolved in 130 parts of a 1: 1 (mass ratio) mixed solvent of ethylene glycol methyl ether acetate and trimethyl phosphate, and the reaction temperature is 160 ° C. The reaction was carried out for 1 hour. Using the thin film distillation can, the obtained reaction liquid was subjected to a second process under the condition of 133 Pa / 160 ° C. for the first time and 13.3 Pa / 200 ° C. for the second time, and excess hexamethylene diisocyanate. The solvent was removed by distillation to obtain a residue. The resulting residue contained 99.9% by weight of polyisocyanate (a hexamethylene diisocyanate burette type polyisocyanate) and 0.1% by weight of residual hexamethylene diisocyanate. The viscosity of the obtained residue was 1900 (± 200) mPa.s. The number average molecular weight was s / 25 ° C., the number average molecular weight was about 600 (± 100), the average number of —NCO functional groups was about 3.3, and the —NCO group content was 23.3 mass%.
To a reactor having a reflux condenser, a thermometer and a stirrer, 80 parts of hydrazine monohydrate was added to 1000 parts of isopropyl alcohol with stirring at room temperature over about 30 minutes, and then the polyisocyanate (NCO group content 23. (3% by mass) A solution of 144 parts dissolved in 576 parts of tetrahydrofuran was added at 10 ° C. over about 1 hour, and further stirred at 40 ° C. for 3 hours, and 1000 parts of water was added. Subsequently, isopropyl alcohol, hydrazine, tetrahydrofuran, water and the like in the obtained reaction solution were distilled off under heating and reduced pressure to obtain 168 parts of a polysemicarbazide compound (PSC) having a biuret structure. When the average number of semicarbazide residues was measured, it was 4.6 meq / g.

[Example 1]
Each component was mixed at 40 ° C. so as to have the following composition to prepare a coating solution. After applying the coating liquid at 40 ° C. with a bar coater heated to 40 ° C. on a sheet made of polyethylene terephthalate (thickness 100 μm) subjected to hydrophilic treatment on the surface, the coating film is immediately applied with cold air at 10 ° C. Blowing started on the surface. At this time, the coating film gelled rapidly after the start of blowing air and was able to maintain a uniform film thickness and a smooth surface. After blowing cold air for 30 seconds, 60 ° C. hot air was blown to the surface of the coating film and dried to obtain a recording medium provided with an ink receiving layer having a thickness of about 25 μm. The evaluation results of this recording medium are shown in Table 1.
Coating liquid composition (dry mass ratio)
Polymer part 1 35 parts lime-processed gelatin obtained in Preparation Example 1 (cow bone raw material, strength 250 bloom, manufactured by Nitta Gelatin Co., Ltd.)
65 parts [Example 2]
Except that the respective components were mixed at 40 ° C. so as to have the following composition to prepare a coating liquid, the same procedure was carried out as in Example 1 to obtain a recording medium provided with an ink receiving layer having a thickness of about 25 μm. The evaluation results of this recording medium are shown in Table 1.
Coating liquid composition (dry mass ratio)
Polymer part 1 35 parts lime-processed gelatin obtained in Preparation Example 1 (cow bone raw material, strength 250 bloom, manufactured by Nitta Gelatin Co., Ltd.)
65 parts polysemicarbazide compound obtained in Preparation Example 4 1 part

[Example 3]
Except that the respective components were mixed at 40 ° C. so as to have the following composition to prepare a coating liquid, the same procedure was carried out as in Example 1 to obtain a recording medium provided with an ink receiving layer having a thickness of about 25 μm. The evaluation results of this recording medium are shown in Table 1.
Coating liquid composition (dry mass ratio)
Polymer part 1 35 parts lime-processed gelatin obtained in Preparation Example 1 (cow bone raw material, strength 250 bloom, manufactured by Nitta Gelatin Co., Ltd.)
65 parts polyvinyl alcohol (GL-500, manufactured by Kuraray Co., Ltd.) 5 parts Polysemicarbazide compound obtained in Preparation Example 4 1 part [Example 4]
Except that the respective components were mixed at 40 ° C. so as to have the following composition to prepare a coating liquid, the same procedure was carried out as in Example 1 to obtain a recording medium provided with an ink receiving layer having a thickness of about 25 μm. The evaluation results of this recording medium are shown in Table 1.
Coating liquid composition (dry mass ratio)
Polymer part 1 35 parts lime-processed gelatin obtained in Preparation Example 1 (cow bone raw material, strength 250 bloom, manufactured by Nitta Gelatin Co., Ltd.)
65 parts polyvinyl alcohol (GL-500, manufactured by Kuraray Co., Ltd.) 5 parts hydroxyethyl cellulose (manufactured by Wako Pure Chemical Industries) 5 parts polysemicarbazide compound obtained in Preparation Example 1 1 part

[Example 5]
Except that the respective components were mixed at 40 ° C. so as to have the following composition to prepare a coating liquid, the same procedure was carried out as in Example 1 to obtain a recording medium provided with an ink receiving layer having a thickness of about 25 μm. The evaluation results of this recording medium are shown in Table 1.
Coating liquid composition (dry mass ratio)
35 parts of polymer compound 1 obtained in Preparation Example 1 Acid-treated gelatin (pig skin raw material, strength 250 bloom, manufactured by Nitta Gelatin Co., Ltd.)
65 parts [Example 6]
Except that the respective components were mixed at 40 ° C. so as to have the following composition to prepare a coating liquid, the same procedure was carried out as in Example 1 to obtain a recording medium provided with an ink receiving layer having a thickness of about 25 μm. The evaluation results of this recording medium are shown in Table 1.
Coating liquid composition (dry mass ratio)
Polymer Compound 2 35 parts lime-processed gelatin obtained in Preparation Example 2 (cow bone raw material, strength 250 bloom, manufactured by Nitta Gelatin Co., Ltd.)
65 parts Cationic polymer (Adeka thioace DM-20A, manufactured by Asahi Denka Kogyo) 5 parts

[Comparative Example 1]
Except that the respective components were mixed at 40 ° C. so as to have the following composition to prepare a coating liquid, the same procedure was carried out as in Example 1 to obtain a recording medium provided with an ink receiving layer having a thickness of about 25 μm. The evaluation results of this recording medium are shown in Table 1.
Coating liquid composition (dry mass ratio)
Lime-processed gelatin (cow bone raw material, strength 250 bloom, Nitta Gelatin Co., Ltd.)
100 parts [Comparative Example 2]
Except that the respective components were mixed at 40 ° C. so as to have the following composition to prepare a coating liquid, the same procedure was carried out as in Example 1 to obtain a recording medium provided with an ink receiving layer having a thickness of about 25 μm. The evaluation results of this recording medium are shown in Table 1.
Coating liquid composition (dry mass ratio)
35 parts of the polymer compound 1 obtained in Preparation Example 1 1 part of the polysemicarbazide compound obtained in Preparation Example 4 [Comparative Example 3]
A recording medium provided with an ink receiving layer having a thickness of about 25 μm was obtained in the same manner as in Comparative Example 2 except that each component was mixed at 40 ° C. so as to have the following composition to prepare a coating liquid. The evaluation results of this recording medium are shown in Table 1.
Coating liquid composition (dry mass ratio)
Polymer Compound 3 35 parts lime-processed gelatin obtained in Preparation Example 3 (cow bone raw material, strength 250 bloom, manufactured by Nitta Gelatin Co., Ltd.)
65 parts polysemicarbazide compound obtained in Preparation Example 4 1 part

When the ink jet recording medium coating liquid, the ink jet recording medium manufacturing method, and the ink jet recording medium of the present invention are used, the image quality such as light resistance, water resistance, and abrasion resistance, which has been difficult with the prior art, is at the same time. This makes it possible to produce recorded products with excellent storage stability with high productivity, and the industrial utility value is extremely large.

Claims (7)

  A coating liquid used in the production of an ink jet recording medium having at least one ink receiving layer provided on at least one side of a support, which is hydrophilic in a temperature range below gelatin and the temperature sensitive point, and in a temperature range exceeding the temperature sensitive point. Then, the coating liquid for inkjet recording media characterized by including the high molecular compound (A) which shows hydrophobicity.   The coating liquid for an ink jet recording medium according to claim 1, wherein the polymer compound (A) forms a polymer emulsion.   The coating liquid for an ink jet recording medium according to claim 1 or 2, wherein the polymer compound (A) has a carbonyl group.   4. The ink jet recording medium coating liquid according to claim 3, comprising at least two hydrazine derivatives having a hydrazine group and / or a semicarbazide group.   The method for producing an ink jet recording medium in which one or more ink-receiving layers are provided on a support, wherein the method for forming at least one layer of the ink-receiving layer is according to any one of claims 1 to 4. An inkjet recording medium comprising a step of coating a coating liquid for an inkjet recording medium on a support at a temperature exceeding the temperature sensitive point of the polymer compound (A) and then cooling to a temperature below the temperature sensitive point. A method for manufacturing a medium.   An inkjet recording medium comprising one or more ink-receiving layers on a support, wherein at least one of the coating layers is a coating for an inkjet recording medium according to any one of claims 1 to 4. An ink-jet recording medium formed using a liquid.   An inkjet recording medium comprising one or more ink-receiving layers on a support, wherein at least one of the coating layers is a coating for an inkjet recording medium according to any one of claims 1 to 4. An ink jet recording medium comprising a liquid-containing component.