JP2006001157A - Recording paper provided with glossy layer and coating liquid for glossy layer - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a recording medium having a surface gloss higher than the conventional surface gloss on a support made of a paper, a sheet, a film, a cloth or the like used in various printing systems performed by a method for adhering an ink composition to a recording medium and an inkjet recording medium having a surface gloss, an image quality and an ink absorbency more excellent than the conventional surface gloss, image quality and ink absorbency. <P>SOLUTION: In this recording paper, a recording layer is provided on at least one side of the support and, further on the recording layer, a glossy layer including a polymeric compound (A), which is hydrophilic in a temperature range lower than a temperature sensing point and hydrophobic in a temperature range exceeding the temperature sensing point, and fine particles (B) is provided. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention provides a high surface using a paper, sheet, film, cloth or the like used as a support for various printing methods by a method of attaching an ink composition to a recording medium or a thermal recording method in which an ink composition is colored by heating. The present invention relates to a glossy recording medium and a coating liquid for obtaining the same, and further relates to an inkjet recording medium excellent in surface gloss, image quality and ink absorbability, and a coating liquid for obtaining the same.

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 technological development of inkjet recording paper having a glossy surface for obtaining high image quality has progressed. However, for such high-surface glossy paper, a plate-like pigment is applied to the surface, and if necessary, So-called cast coating, obtained by copying the mirror surface by applying pressure to a heated drum surface that has a mirror surface and drying the coated paper with high gloss that has been subjected to calendering treatment or a wet coating layer. Paper is known. This cast coated paper has a high surface gloss and superior surface smoothness compared to ordinary coated paper with a super calender finish, and has an excellent printing effect. Although it is exclusively used, it has various difficulties when used for inkjet recording paper. For example, as disclosed in Patent Document 1, a conventional cast coated paper is obtained by copying a mirror roll surface of a cast coater with a film-forming substance such as an adhesive in a pigment composition constituting the coating layer. High gloss is obtained. On the other hand, the presence of the film-forming substance loses the porosity of the coating layer, and has problems such as extremely reducing the absorption of ink during ink jet recording. In order to improve the ink absorbability, it is important to make the cast coating layer porous so that the ink can be easily absorbed. For this purpose, it is necessary to reduce the film-forming substance. However, when the amount of the film-forming substance is reduced, the surface gloss is lowered as a result, and it is difficult to satisfy both the surface gloss of the cast coated paper and the ink jet recording suitability at the same time.
However, in recent years, with the expansion of applications such as high speed inkjet recording, high definition of recorded images, and full color, higher gloss, higher image quality, and higher recording density have been demanded. Development of ink jet recording paper having gloss and recording quality comparable to photographic paper is demanded.
Furthermore, recording media used for thermal recording methods that print by coloring the ink composition by heating, gravure printing, offset printing, and other various printing methods are also sufficient from the standpoint of surface glossiness and high image quality. Development of a recording medium that can satisfy the requirements and an efficient manufacturing method thereof is demanded.

US Pat. No. 5,275,846

  The object of the present invention is to provide a surface gloss higher than that of a conventional paper, sheet, film, cloth or the like used in various printing methods performed by a method of attaching an ink composition to a recording medium. The present invention also provides an ink jet recording medium having superior surface gloss, image quality, and ink absorptivity as compared with conventional recording media.

As a result of intensive studies to solve the above problems, the present inventors have provided a recording layer on at least one surface of the support, and on the recording layer, the recording layer has hydrophilicity in a temperature region below the temperature sensitive point. It has been found that a recording paper provided with a glossy layer containing a polymer compound (A) exhibiting hydrophobicity in a temperature range exceeding the temperature sensitive point is effective in solving the above problems, and has led to the present invention. It was. That is, the present invention is as follows.
1) A polymer having a recording layer provided on at least one surface of a support, and having a hydrophilic property in a temperature region below the temperature sensitive point and a hydrophobic property in a temperature region exceeding the temperature sensitive point on the recording layer. A recording paper provided with a glossy layer containing the compound (A) and fine particles (B).
2) It is obtained by a process including coating the gloss layer on the recording layer and pressing the gloss layer to a heated mirror roll while the coated gloss layer is in a wet state. The recording paper according to 1) of the invention.
3) The recording paper of the invention of 1) or 2), wherein the recording paper is an inkjet recording medium.
4) A coating liquid used for the glossy layer coating of the recording paper according to any one of 1) to 3), wherein the polymer compound (A) forms an emulsion in the coating liquid. The coating liquid characterized by the above.

  By using the present invention, the surface gloss is higher than the conventional one using a paper, sheet, film, cloth or the like used as a support for various printing methods performed by a method of attaching an ink composition to a recording medium. In addition, it is possible to provide an inkjet recording medium having superior surface gloss, image quality, and ink absorptivity compared to conventional recording media.

The present invention will be specifically described below.
In the present invention, as a support, for example, high-quality paper, photographic paper base paper, drawing paper, image paper, art paper, coated paper, cast paper, kraft paper, and the like, nonwoven fabric, film, synthetic paper, etc. are appropriately used. Can be used according to. In an embodiment in which the wet glossy layer is pressure-bonded and dried on a heated mirror roll, a film or synthetic paper is permeable. The support may be transparent or opaque as long as it has air permeability, but paper is preferably used from the viewpoint of air permeability, and further, the texture and gloss of photographic paper for silver salt photography. From the viewpoint of obtaining a photographic paper, a photographic paper base paper not coated with a resin such as polyethylene is preferably used.
In the present invention, a recording layer described later is provided on the support, and then a glossy layer is provided on the recording layer. Two or more recording layers can be provided. Here, the recording layer refers to a coating layer having a coating amount that substantially functions as an ink absorbing layer in the case of recording paper used for printing by an ink jet printer, and in the case of thermal recording paper, color development. Means a layer containing an agent and a developer. The glossy layer has a function of improving the surface gloss of the recording layer.
A recording sheet provided with a glossy layer containing a polymer compound (A) that exhibits a hydrophilic property in a temperature region below the temperature sensitive point and a hydrophobic property in a temperature region above the temperature sensitive point is excellent on the recording layer. The reason for this is that when the coating liquid for glossy layer coating of the present invention is applied onto the recording layer, the solid content in the coating liquid hardly penetrates into the recording layer, and the surface is smooth. It is presumed to form a highly homogeneous surface with high properties. The reason why the solid content in the coating liquid is difficult to penetrate into the recording layer is that the gloss layer coating coating liquid of the present invention has a low viscosity in the temperature range exceeding the temperature sensitive point of the polymer compound (A), It is presumed to be related to thickening in the temperature range below the temperature sensitive point of the polymer compound (A). In the present invention, the gloss layer coating coating solution is preferably used for coating in a temperature range exceeding the temperature sensitive point of the polymer compound (A).

  The polymer compound (A) used in the present invention exhibits hydrophilicity in a temperature range below the temperature sensitive point and is hydrophobic in a temperature range above the temperature sensitive point. A homopolymer of a monomer (hereinafter referred to as a main monomer (M)) from which a polymer compound exhibiting a hydrophilic-hydrophobic change in accordance with the copolymer is obtained, or a copolymer of two or more types of main monomers (M). A monomer (hereinafter referred to as a sub-monomer (hereinafter referred to as a sub-monomer), which can be reacted with the main monomer (M) to form a polymer compound and which does not yield a polymer compound exhibiting the temperature responsiveness by homopolymerization). N))) and a main monomer (M). The main monomer (M) and the submonomer (N) can be used alone or in combination of two or more.

A polymer compound having high temperature responsiveness can be obtained by homopolymerization of the main monomer (M), but the main monomer (M) is homopolymerized by copolymerizing the main monomer (M) and the submonomer (N). A polymer compound (A) having a temperature sensitive point different from that of the polymer compound can be obtained, or a polymer compound (A) having a film-forming property different from the homopolymerized polymer compound of the monomer (M) can be obtained. it can.
The main monomer (M) 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) acryloylpiperidine, 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 (N) include lipophilic vinyl compounds, hydrophilic vinyl compounds, and ionic vinyl compounds. Specific examples of lipophilic vinyl compounds 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.

The copolymerization ratio of the main monomer (M) and the submonomer (N) is determined within a range in which the obtained copolymer polymer compound exhibits temperature responsiveness in which hydrophilicity and hydrophobicity change at a certain temperature as a boundary. It is done. That is, when the proportion of the submonomer (N) is too large, the copolymeric polymer compound obtained does not exhibit the temperature responsiveness.
That is, the copolymerization ratio of the main monomer (M) and the submonomer (N) depends on the combination of the monomer species used, but the ratio of the submonomer (N) in the resulting polymer compound is preferably 50% by mass or less. More preferably, it is 30 mass% or less. Moreover, 0.01 mass% or more is preferable in order that the addition effect of a submonomer (N) may be expressed better.

  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. In the present invention, 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 temperature-sensitive point of the polymer compound (A) is determined as a transition point at which the temperature-viscosity curve obtained by measuring the viscosity of the polymer compound changes rapidly.

The polymer compound (A) of the present invention may be anionic, cationic, nonionic or amphoteric, but is preferably cationic from the viewpoint of the surface gloss of the resulting recording paper.
The cationic polymer compound (A) can be obtained, for example, by including an ethylenically unsaturated monomer having a cationic group as a secondary monomer (N) used for polymerization. The ethylenically unsaturated monomers having a cationic group can be used alone or in combination of two or more.
Examples of the ethylenically unsaturated monomer having a cationic group include vinyloxyethyltrimethylammonium chloride, 2,3-dimethyl-1-vinylimidazolinium chloride, and trimethyl- (3- (meth) acrylamide-3,3-dimethyl. Propyl) ammonium chloride, trimethyl- (3-methacrylamidopropyl) ammonium chloride, trimethyl- (3-acrylamidopropyl) ammonium chloride, N- (1,1-dimethyl-3-dimethylaminopropyl) (meth) acrylamide and its 4 Quaternary ammonium salt, trimethyl- (3- (meth) acrylamide) ammonium chloride, 1-vinyl-2-methyl-imidazole, 1-vinyl-2-ethyl-imidazole, 1-vinyl-2-phenyl-imi Sol, 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-butylaminoethyl (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) methacrylamide and its quaternary ammonium salt, N- (3-diethylaminopropyl) acrylamide and its 4 Ammonium salt, o-, m-, p-aminostyrene and its quaternary ammonium salt, o-, m-, p-vinylbenzylamine and its quaternary ammonium salt, N- (vinylbenzyl) pyrrolidone, N- (vinyl Benzyl) 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 quaternary ammonium salt, 2-, or 4-vinylquinoline and its quaternary ammonium salt Etc. are exemplified. In particular, from the viewpoint of the surface gloss of the resulting recording paper, for example, N, N-dimethylaminopropyl (meth) acrylate, N, N-dimethylaminoethyl (meth) acrylate, N, N-diethylaminoethyl (meth) acrylate, t -Butylaminoethyl (meth) acrylate, N- (3-dimethylaminopropyl) methacrylamide, N- (3-dimethylaminopropyl) acrylamide, N- (3-diethylaminopropyl) methacrylamide, N- (3-diethylaminopropyl) ) Acrylamide is preferably used.

The copolymerization ratio of the main monomer (M) and the submonomer (N) containing the ethylenically unsaturated monomer having the cationic group is such that the obtained copolymer polymer compound has hydrophilicity and hydrophobicity with the temperature sensitive point as a boundary. It is determined within a range exhibiting reversible temperature response.
The preferred content of the ethylenically unsaturated monomer unit having a cationic group in the polymer compound (A) used in the present invention varies depending on the type and combination of the monomers used. From the viewpoint of the above, 0.01 mass% or more is preferable, and from the viewpoint of film formability, 50 mass% or less is preferable. More preferably, it is 0.1-30 mass%.
The anionic polymer compound (A) can be obtained, for example, by including an ethylenically unsaturated monomer having an anionic group as a secondary monomer (N) used for polymerization. The ethylenically unsaturated monomers having an anionic group can be used alone or in combination of two or more.
Examples of the ethylenically unsaturated monomer having an anionic group include acrylic acid, methacrylic acid, itaconic acid, fumaric acid, maleic acid, crotonic acid, butenetricarboxylic acid, monoethyl maleate, monomethyl maleate, monoethyl itaconate, and itaconic acid. Examples include carboxylic acid group-containing monomers such as monomethyl, and sulfonic acid group-containing monomers such as 2-acrylamido-2-methyl-propanesulfonic acid, styrenesulfonic acid, vinylsulfonic acid, and (meth) acrylsulfonic acid. It is preferable to use carboxylic acid group-containing monomers such as methacrylic acid, itaconic acid, fumaric acid and maleic acid.
The copolymerization ratio of the main monomer (M) and the submonomer (N) containing the ethylenically unsaturated monomer having an anionic group is such that the obtained copolymer polymer compound has hydrophilicity and hydrophobicity with the temperature sensitive point as a boundary. It is determined within a range exhibiting reversible temperature response.
The preferred content of the ethylenically unsaturated monomer unit having an anionic group in the polymer compound (A) used in the present invention varies depending on the type and combination of the monomers used. From the viewpoint of the above, 0.01 mass% or more is preferable, and from the viewpoint of film formability, 30 mass% or less is preferable. More preferably, it is 0.1-10 mass%.

The glass transition point of the polymer compound (A) used in the present invention is preferably −50 to 150 ° C. from the viewpoints of film formability and the flexibility of the recording medium to be obtained. From the viewpoint of imparting flexibility, −50 to 30 ° C. is preferable. However, when the polymer emulsion of the present invention is used for the production of an inkjet recording medium, it is preferably 30 to 130 ° C. when the ink absorbability of the obtained inkjet recording medium is important. When importance is attached to flexibility and transparency of the ink absorbing layer, -50 to 30 ° C is preferable.
In the present invention, from the viewpoint of surface glossiness of the resulting inkjet recording paper, the polymer compound (A) preferably forms a polymer emulsion in the coating solution before coating. Therefore, when producing the polymer compound (A), it is preferable to carry out the polymerization reaction in an aqueous solvent 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, a widely known polymer emulsion production technique can be used in the temperature region. Specifically, a surfactant is dissolved in water, and the copolymerization monomer component such as the main monomer (M) and the submonomer (N) is added and emulsified, and a 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 the polymer compound (A) emulsion used in the present invention, it is preferable to use a surfactant.
The polymer compound (A) emulsion used in the present invention may be any of anionic, cationic, nonionic and amphoteric, but is preferably cationic from the viewpoint of the surface gloss of the resulting recording paper.
When the polymer compound (A) emulsion 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, higher fatty acid and amino acid condensate, dialkylsulfosuccinate ester salt, naphthenate salt, alkyl ether carboxylate, acylated peptide, α-olefin sulfonate, N-acylmethyl taurine, 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, and polyglycerin fatty acid ester.

When the polymer compound (A) emulsion 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 thereof 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 compound (A) emulsion 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, and polyglycerin fatty acid ester.
In the case where the polymer compound (A) emulsion is amphoteric, it is preferable to use an amphoteric surfactant from the viewpoint of stability against changes in pH of the polymer compound (A) emulsion. In the case where the polymer compound (A) emulsion is cationic, a cationic surfactant can be used, and the polymer compound (A) emulsion exhibits anionic property in the coating liquid of the present invention. In some cases, an anionic surfactant 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 50 parts by mass, more preferably 1 to 30 parts by mass with respect to 100 parts by mass of the resin solid content of the polymer compound (A) emulsion. is there.
In this invention, the said surfactant can also be used individually by 1 type, and can also use 2 or more types together.

The average particle diameter of the polymer compound (A) emulsion particles used in the present invention is preferably from 10 to 600 nm from the viewpoint of the film-forming property of the coating layer and the production efficiency of the polymer compound (A) emulsion. Preferably it is 10-300 nm, Most preferably, it is 20-100 nm. The average particle size referred to here is the number average particle size of the polymer compound (A) emulsion measured by a dynamic light scattering method in a temperature range where the polymer compound (A) exhibits hydrophobicity.
In the present invention, it is preferable that the glossy layer contains a hydrophilic organic polymer compound from the viewpoint of adhesion of the fine particles (B) described later. Examples of the hydrophilic organic polymer compound include gelatin or gelatin derivatives, polyvinyl pyrrolidone, pullulan, polyvinyl alcohol or derivatives thereof, polyethylene glycol, carboxymethyl cellulose, hydroxyethyl cellulose, dextran, dextrin, polyacrylic acid and salts thereof, agar, κ Carrageenan, λ-carrageenan, ι-carrageenan, xanthene gum, locust bean gum, alginic acid, gum arabic, pullulan, for example, polyalkylene oxide copolymerizables described in JP-A-7-195826 and 7-9757 A polymer, water-soluble polyvinyl butyral, or a vinyl monomer having a carboxyl group or a sulfonic acid group described in, for example, JP-A-62-245260, or these Mention may be made of the polymers of the copolymers having repeat vinyl monomers. These hydrophilic organic polymer compounds may be used alone or in combination of two or more. A preferred hydrophilic organic polymer compound is polyvinyl alcohol or a derivative thereof, gelatin or a gelatin derivative, particularly preferably polyvinyl alcohol.

The polyvinyl alcohol preferably used in the present invention has an average degree of polymerization of 300 to 4000, and particularly those having an average degree of polymerization of 1000 or more have good viscosity increase at the time of coating, It is more preferable because the film strength is good. The saponification degree of polyvinyl alcohol is preferably 70 to 100%, particularly preferably 80 to 100%.
When the hydrophilic organic polymer compound is used, the ratio of the hydrophilic organic polymer compound to the fine particles (B) is dried from the viewpoint of the effect of adding the hydrophilic organic polymer compound and the surface gloss of the resulting recording medium. It is 1: 100-30: 100 by mass ratio, Preferably it is the range of 3: 100-15: 100.

In the glossy layer of the present invention, the hydrophilic organic polymer compound is preferably hardened with a hardener from the viewpoint of improving the scratch resistance of the recording paper surface.
The hardener is generally a compound having a functional group capable of reacting with the hydrophilic organic polymer compound or a compound that promotes the reaction between the functional groups of the hydrophilic organic polymer compound. It is appropriately selected according to the type of organic polymer compound.
Specific examples of hardeners include, for example, epoxy hardeners (diglycidyl ethyl ether, ethylene glycol diglycidyl ether, 1,4-butanediol diglycidyl ether, 1,6-diglycidyl cyclohexane, N, N— Diglycidyl 4-glycidyloxyaniline, sorbitol polyglycidyl ether, glycerol polyglycidyl ether, etc.), aldehyde hardeners (formaldehyde, glioxal, etc.), active halogen hardeners (2,4-dichloro-4-hydroxy-1, 3,5-s-triazine, etc.), active vinyl compounds (1,3,5-trisacryloyl-hexahydro-s-triazine, bisvinylsulfonylmethyl ether, etc.), boric acid and its salts, borax, aluminum alum, etc. Is mentioned.
When polyvinyl alcohol is used as a particularly preferred hydrophilic organic polymer compound, from the viewpoint of the coating strength of the coating layer, at least one hard material selected from boric acid and its salts and / or epoxy hardeners is used. A film agent is preferably used, and boric acid and / or borax are most preferable from the viewpoint of coating liquid thickening (gelation) immediately after coating.

The amount of the hardener used varies depending on the type of hydrophilic organic polymer compound, the type of hardener, the type of fine particles (B), the ratio to the hydrophilic organic polymer compound, and the like. The amount is 1 to 200 mg, preferably 5 to 100 mg, per 1 g of the compound.
When gelatin is used as the hydrophilic organic polymer compound, the following compounds known as gelatin hardeners can be used. For example, aldehyde compounds such as formaldehyde, glyoxal, glutaraldehyde, ketone compounds such as diacetyl and cyclopentanedione, bis (2-chloroethylurea) -2-hydroxy-4,6-dichloro-1,3,5- Active halogen compounds such as triazine, 2,4-dichloro-6-S-triazine sodium salt, divinylsulfonic acid, 1,3-vinylsulfonyl-2-propanol, N, N′-ethylenebis (vinylsulfonylacetamide) ), Active vinyl compounds such as 1,3,5-triacryloyl-hexahydro-S-triazine, N-methylol compounds such as dimethylolurea and methyloldimethylhydantoin, isocyanate compounds such as 1,6-hexamethylene diisocyanate, For example, U.S. Pat. Aziridine compounds described in U.S. Pat. No. 983611, such as carboximide compounds described in U.S. Pat. No. 3,100,704, epoxy compounds such as glycerol triglycidyl ether, 1,6-hexamethylene-N, N ′ -Ethyleneimino compounds such as bisethyleneurea, halogenated carboxaldehyde compounds such as mucochloric acid and mucophenoxycyclolic acid, dioxane compounds such as 2,3-dihydroxydioxane, chromium alum, potash alum, zirconium sulfate, Such as chromium acetate. In addition, the said hardening agent may be single 1 type, or may combine 2 or more types.

  The above hardener is preferably used by dissolving the hardener in water and / or an organic solvent from the viewpoint of ease of adjustment of the coating liquid, stability, and the like. The concentration of the hardener in the hardener solution is preferably 0.05 to 20 mass%, particularly preferably 1 to 10 mass%, based on the total mass of the hardener solution. As a solvent constituting the hardener solution, water is generally used, and an aqueous mixed solvent containing an organic solvent miscible with water may be used. The organic solvent can be arbitrarily used as long as it can dissolve the hardener, and examples thereof include alcohols such as methanol, ethanol, isopropyl alcohol and glycerin; ketones such as acetone and methyl ethyl ketone; methyl acetate and ethyl acetate. An ester such as toluene; an aromatic solvent such as toluene; an ether such as tetrahydrofuran; and a halogenated carbon-based solvent such as dichloromethane.

It is preferable to add a crosslinking agent capable of crosslinking the polymer compound (A) to the glossy layer coating liquid from the viewpoint of the strength and water resistance of the recording paper.
In particular, it is industrially desirable that the crosslinking reaction does not proceed in the coating solution before coating, but the crosslinking reaction proceeds after coating. The reaction is preferably a reaction of a carbonyl group with a hydrazine group or a semicarbazide group. That is, it is preferable to polymerize the polymer compound (A) having a carbonyl group and use a hydrazine derivative having a hydrazine group and / or a semicarbazide group as a crosslinking agent.
The polymer compound (A) containing a carbonyl group is obtained, for example, by copolymerizing a main monomer (M) and a submonomer (N) containing a monomer containing a carbonyl group. The main monomer (M) and the submonomer (N) containing a monomer containing a carbonyl group can be used alone or in combination of two or more. As for the copolymerization ratio of the main monomer (M) and the submonomer (N) containing the carbonyl group-containing monomer, the hydrophilicity and hydrophobicity of the obtained copolymeric polymer compound change reversibly at the temperature sensitive point. It is determined within a range exhibiting temperature responsiveness.

The content of the carbonyl group-containing monomer unit in the polymer compound (A) is preferably from 0.01 to 50 mass%, more preferably from 0.1 to 20 mass%, from the viewpoint of film formability.
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. .

  When the polymer compound (A) contains a carbonyl group, it is possible to use a hydrazine derivative having at least two hydrazine groups and / or semicarbazide groups as a crosslinking agent in the coating liquid used for the glossy layer. This is preferable from the viewpoint of water resistance and strength of the paper. A coating layer containing a compound having a molecular structure in which a carbonyl group site is cross-linked by a hydrazine derivative by adding, mixing, coating and drying the hydrazine derivative to a coating solution containing the polymer compound (A). Can be obtained. As the hydrazine derivative, a compound having at least two hydrazine groups and / or a semicarbazide group is used. Among these, examples of the compound having a hydrazine group include carbohydrazide, isophthalic acid dihydrazide, 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-dihydrazine, butylene-1 1,4-dihydrazine, hydrazine hydrate and the like are exemplified, and examples of the compound having a semicarbazide group include a product obtained by reaction of a polyisocyanate compound and the hydrazine compound. It is. As the hydrazine derivative, a compound having a semicarbazide group is preferable because the resulting recording paper has high water resistance. The content of the hydrazine derivative is preferably 0.01 to 10 times the molar amount of the carbonyl group-containing monomer unit in the obtained polymer compound (A).

Various means such as various blade coaters, roll coaters, air knife coaters, bar coaters, rod blade coaters, curtain flow coaters, gate roll coaters, short dwell coaters, extrusion die coaters, size presses, sprays, etc. The device can be used on-machine or off-machine.
As a material of the mirror surface roll in the means for press-bonding the gloss layer to a heated mirror surface roll in a wet state (cast method), for example, a metal such as stainless steel, glass, polyacryl, polyethylene terephthalate, silicone resin, Fluorine resin and the like can be mentioned, but metals such as stainless steel are currently most preferred from the viewpoint of surface smoothness and are preferably used. Preferred shapes are cylindrical, flat and the like, but cylindrical is preferably used.

As the casting method, there are a wet casting method (direct method), a gelled casting method (solidification method), and a rewet casting method (rewetting method). The direct method is a method in which a recording layer is coated and then dried by pressing it onto a heated mirror roll in an undried state (wet state). It is a method of coagulating by contacting with an alkali solution or the like, and then crimping to a heated mirror roll. The solidification method also includes a thermal solidification method in which the surface of the recording layer is irradiated with infrared rays to solidify the surface. The rewet method is a method in which a recording layer is coated and dried, then the recording layer is rewetted with a liquid mainly composed of water, and is pressed onto a heated mirror roll and dried. In the present invention, any casting method may be used as necessary, but the direct method is most preferable from the viewpoint of productivity.
When high gloss is applied to the surface of the coating layer by the casting method, an ink jet recording paper that can give a high resolution image with no microcracks or very few microcracks can be produced.
The coating liquid for glossy layer coating of the present invention is adjusted to a solid content concentration of about 5 to 65% by mass, and is 0.2 to 10 g / m ² in dry weight on the recording layer described later, preferably 1 to 5 g. The coating is performed by the above-described coating method so as to be / m ² .

The inclusion of fine particles (B) in the glossy layer is preferable from the viewpoint of the abrasion resistance of the surface of the obtained recording medium and the ink absorbency when printing on the obtained recording medium using an ink jet printer.
The ratio of the fine particles (B): (the polymer compound (A) and the hydrophilic organic polymer compound) is determined by printing the surface of the obtained recording medium using an ink jet printer from the viewpoint of abrasion resistance. From the viewpoint of ink absorbency at the time of carrying out, the dry mass ratio is preferably 100: 5 to 100: 60, more preferably 100: 10 to 100: 40. However, the hydrophilic organic polymer compound is not an essential component in the present invention.
In the present invention, the fine particles (B) may be organic compounds or inorganic compounds. When the fine particle (B) is an organic compound, for example, a conventionally known poly (meth) acrylate type, polyvinyl acetate type, vinyl acetate-acrylic type obtained by radical polymerization, anionic polymerization, cationic polymerization, etc. in an aqueous medium, Ethylene vinyl acetate, silicone, polybutadiene, styrene butadiene, NBR, polyvinyl chloride, chlorinated polypropylene, polyethylene, polystyrene, vinylidene chloride, polystyrene- (meth) acrylate, styrene-anhydrous malee Examples include acid-based copolymers, three-dimensional crosslinked resins, and silicone-modified acrylic, fluorine-acrylic, acrylic silicone, and epoxy-acrylic modified copolymers. The above can be contained. In particular, an ink in which an organic polymer compound classified into a poly (meth) acrylate (acrylic polymer compound) and / or polystyrene- (meth) acrylate (styrene-acrylic polymer compound) is finally obtained. It is preferably used from the viewpoints of transparency of the absorbing layer, light yellowing resistance, and storage stability of the resulting recording paper.

  The fine particles (B) in the case of an organic polymer compound are preferably obtained as a polymer emulsion, and can be obtained by using a widely known polymer emulsion production technique. In addition to the method of emulsifying by adding a monomer component to be described later, emulsifying, adding a radical polymerization initiator and carrying out emulsion polymerization by a batch charging reaction, the reaction system can be added to the reaction system by methods such as continuous dripping and divided addition. The method of supplying the said copolymerization component and a radical polymerization initiator to a reaction system is mentioned.

  As the monomer for obtaining the fine particles (B) in the case of an organic polymer compound, one or a combination of two or more ethylenically unsaturated monomers can be used. Specifically, for example, (meth) Acrylic acid esters, (meth) acrylamide monomers, vinyl cyanides and the like. Examples of (meth) acrylic acid esters include (meth) acrylic acid alkyl esters having 1 to 18 carbon atoms in the alkyl portion, for example, (Meth) acrylic acid hydroxyalkyl ester having 1 to 18 carbon atoms in the alkyl part, (poly) oxyethylene (meth) acrylate having 1 to 100 ethylene oxide groups, and 1 to 100 propylene oxide groups (Poly) oxypropylene (meth) acrylate of 1 to 100 ethylene oxide groups (poly Oxyethylene di (meth) acrylate. Specific examples of (meth) acrylic acid alkyl ester having 1 to 18 carbon atoms in the alkyl part include, for example, methyl (meth) acrylate, ethyl (meth) acrylate, n-butyl (meth) acrylate, (meth). Examples include 2-ethylhexyl acrylate, cyclohexyl (meth) acrylate, methyl cyclohexyl (meth) acrylate, dodecyl (meth) acrylate, and the like. Specific examples of the (meth) acrylic acid hydroxyalkyl ester having 1 to 18 carbon atoms in the alkyl moiety include, for example, 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, and (meth) acrylic acid. Examples include 2-hydroxycyclohexyl and dodecyl (meth) acrylate. Specific examples of the (poly) oxyethylene (meth) acrylate having 1 to 100 ethylene oxide groups include, for example, ethylene glycol (meth) acrylate, ethylene glycol methoxy (meth) acrylate, and diethylene glycol (meth) acrylate. , Methoxy (meth) acrylic acid diethylene glycol, (meth) acrylic acid tetraethylene glycol, methoxy (meth) acrylic acid tetraethylene glycol, and the like. Specific examples of the (poly) oxypropylene (meth) acrylate having 1 to 100 propylene oxide groups include, for example, propylene glycol (meth) acrylate, propylene glycol methoxy (meth) acrylate, and dimethacrylate (meth) acrylate. Examples include propylene glycol, dipropylene glycol methoxy (meth) acrylate, tetrapropylene glycol (meth) acrylate, and tetrapropylene glycol methoxy (meth) acrylate. Specific examples of the (poly) oxyethylene di (meth) acrylate having 1 to 100 ethylene oxide groups include, for example, ethylene glycol di (meth) acrylate, diethylene glycol di (meth) acrylate, and methoxy (meth) acryl. Examples include acid diethylene glycol, di (meth) acrylic acid tetraethylene glycol, and the like. Examples of (meth) acrylamide monomers include (meth) acrylamide, N-methylol (meth) acrylamide, N-butoxymethyl (meth) acrylamide, and diacetone acrylamide. Examples of vinyl cyanides include (meta) ) Acrylonitrile and the like. Specific examples other than the above include, for example, olefins such as ethylene, propylene and isobutylene, dienes such as butadiene, haloolefins such as vinyl chloride and vinylidene chloride, vinyl acetate, vinyl propionate, vinyl n-butyrate, and benzoate. Carboxylic acid vinyl esters such as vinyl acid, vinyl tert-butylbenzoate, vinyl pivalate, vinyl 2-ethylhexanoate, vinyl versatic acid, vinyl laurate, carboxylic acids such as isopropenyl acetate and isopropenyl propionate Isopropenyl esters, ethyl vinyl ether, isobutyl vinyl ether, vinyl ethers such as cyclohexyl vinyl ether, styrene derivatives such as styrene and methylstyrene, aromatic vinyl compounds such as vinyl toluene, allyl acetate, allyl benzoate, etc. Allyl esters such as allyl esters, allyl ethyl ether, allyl glycidyl ether, allyl phenyl ether, γ- (meth) acryloxypropyltrimethoxysilane, vinylmethyldiethoxysilane, vinylmethyldimethoxysilane, vinyldimethylethoxysilane, Vinyldimethylmethoxysilane, vinyltrimethoxysilane, vinyltriethoxysilane, 4- (meth) acryloyloxy-2,2,6,6-tetramethylpiperidine, 4- (meth) acryloyloxy-1,2,2,6 , 6-pentamethylpiperidine, perfluoromethyl (meth) acrylate, perfluoropropyl (meth) acrylate, perfluoropropylmethyl (meth) acrylate, vinyl pyrrolidone, trimethylolpropane tri (meth) ) Acrylate, glycidyl (meth) acrylate, 2,3-cyclohexene oxide (meth) acrylate, allyl (meth) acrylate, acid phosphooxyethyl methacrylate, 3-chloro-2-acid phosphooxypropyl methacrylate, methyl Examples thereof include propanesulfonic acid acrylamide, divinylbenzene and the like. Here, (meth) acryl is a simple description of methacryl (or methacryl) or acryl.

When the organic polymer compound is used, the glass transition point of the fine particles (B) is preferably 30 to 130 ° C. when the ink absorbability of the obtained recording paper is important, and the flexibility of the resulting recording paper is important. Is preferably -50 to 30 ° C.
When the fine particles (B) are inorganic compounds, for example, light calcium carbonate, heavy calcium carbonate, magnesium carbonate, kaolin, clay, talc, calcium sulfate, barium sulfate, titanium dioxide, zinc oxide, zinc hydroxide, zinc sulfide, carbonate Zinc, hydrotalcite, aluminum silicate, diatomaceous earth, calcium silicate, magnesium silicate, synthetic amorphous silica, colloidal silica, dry silica, alumina, colloidal alumina, pseudoboehmite alumina, aluminum hydroxide, zeolite, magnesium hydroxide, etc. Examples include metal oxides such as zirconium, titanium, tantalum, niobium, tin, and tungsten, and metal phosphates such as aluminum, vanadium, zirconium, and tungsten, in which a part of the inorganic compound is substituted with another element. And organic matter Those that modify the surface by modifying can also be used. Among these inorganic fine particles, one type may be used alone, or two or more types may be used.

In particular, it is preferable to use colloidal silica, dry silica, alumina sol, or pseudo boehmite alumina fine particles as the fine particles (B).
By using colloidal silica or dry silica, a recording paper with high surface gloss can be obtained. Examples of the colloidal silica include anionic colloidal silica and cationic colloidal silica obtained by a method of reacting a polyvalent metal compound such as an aluminum ion. As the dry silica, for example, vapor phase silica synthesized by burning silicon tetrachloride with hydrogen and oxygen is preferably used. The dry method silica may be used as it is, or a surface modified with a silane coupling agent or the like. Further, it is preferable to use alumina sol or pseudo boehmite-based alumina fine particles because the image quality when printed on the obtained ink jet recording paper is improved.
The fine particles (B) used in the present invention may be used as primary particles or in a state in which secondary particles are formed. Further, the particle diameter of the fine particles (B) is preferably fine particles (B) having a number average particle diameter of 500 nm or less, more preferably 100 nm or less in order to obtain a recording paper having a high gloss surface. More preferably, those having a thickness of 50 nm or less are used. The lower limit of the particle diameter of the fine particles (B) is desirably a number average particle diameter of about 3 nm or more from the viewpoint of production efficiency of the fine particles (B). The number average particle size referred to here is a number average particle size measured by a dynamic light scattering method.

When the recording paper of the present invention is used for printing using an ink jet printer, it is preferable that the gloss layer contains the cationic polymer (C) to improve the water resistance of the printing portion. As the cationic polymer (C), for example, those containing at least one of primary amine, secondary amine, tertiary amine substituents and salts thereof, and quaternary ammonium salt substituents are preferably used. Examples thereof include dimethyldiallylammonium chloride polymer, dimethyldiallylammonium chloride-acrylamide copolymer, alkylamine polymer, polyamine dicyan polymer, and polyallylamine hydrochloride. The cationic polymer (C) preferably has a weight average molecular weight of 1,000 to 200,000. The amount of the cationic polymer (C) used is preferably 0.1 to 100 parts by mass, more preferably 10 to 30 parts by mass from the viewpoint of the water resistance of the coating film with respect to 100 parts by mass of the fine particles (B) in dry mass. Preferably used.
As the solvent used in the gloss layer coating liquid used in the present invention, a water-soluble solvent such as alcohol, ketone, 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 recording layer contains the fine particles (B) and the adhesive for adhering the fine particles (B). As the adhesive, the above-mentioned hydrophilic organic polymer compound and / or polymer compound (A) can be used alone or in combination of two or more. The ratio of fine particles (B): adhesive at that time is preferably 100: 5 to 100: 100, more preferably 100: 10 to 100: 40, in terms of dry mass ratio.
In the case where the recording paper of the present invention is used for printing using an ink jet printer, the recording layer preferably contains the above-mentioned cationic polymer (C) from the viewpoint of ink fixability. The content of the cationic polymer (C) is preferably 100: 0.5 to 100: 30, more preferably 100: 2 to 100: 15, in terms of the dry mass ratio of fine particles (B): cationic polymer (C). .
The recording layer composition, and the solid concentration was adjusted to about 5 to 65 wt%, 1 to 50 g / m ² dry weight on the support of the above, as preferably a 2 to 20 g / m ² It is coated and dried by various publicly known coating apparatuses such as a blade coater, an air knife coater, a roll coater, a brush coater, a chamber coater, a bar coater and a gravure coater. Furthermore, if necessary, after the recording layer is dried, a smoothing process such as super calendering or brushing can be performed.
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.

Hereinafter, the present invention will be described based on examples.
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) emulsion used in the present invention is the temperature of the polymer emulsion in which the concentration of the polymer compound (A) is adjusted to 5% by mass with an aqueous solvent while maintaining a temperature equal to or higher than the polymerization temperature. The viscosity of the emulsion was measured after gradually decreasing, and the transition point at which the temperature-viscosity curve changed rapidly was determined as the temperature sensitive point of the polymer compound (A) emulsion.
Evaluation of the following items (uniformity of the solid printing part, bleeding of the solid printing part, white paper gloss, comprehensive judgment of the printing quality) was performed using a commercially available inkjet printer (PM-900C manufactured by Seiko Epson). It was. White paper gloss means the surface gloss of an unprinted portion of a recording sheet.
(Uniformity of solid printing part)
The printing unevenness of the solid printing portion of the two-color mixture of cyan ink and magenta ink was visually evaluated.
○: Printing unevenness is not seen and is a good level.
(Triangle | delta): There is almost no printing nonuniformity and the level which does not become a problem practically.
X: Level at which printing unevenness is remarkable and becomes a serious problem in practical use.
(Bleeding of solid printing part)
The blur of the two-color mixed solid printing portion was visually and sensuously evaluated.
○: Bleeding is not seen and is a good level.
Δ: Slight bleeding is observed.
X: A level that causes significant bleeding and is a serious problem in practical use.
(White paper gloss)
The glossiness of the blank paper portion and the black solid print portion was evaluated sensuously by looking at the reflection of the fluorescent lamp. The evaluation result was evaluated by a 10-level evaluation. The extremely good result was 10, the good result was 8, the slightly good result was 6, the slightly inferior result was 2, the inferior result was 2, and the extremely inferior result was 1.
(Comprehensive evaluation)
Full-color photographic images were printed and evaluated comprehensively for print quality such as gloss, image quality, optical density of printed parts, and clarity. The evaluation result was evaluated by a 10-level evaluation. The extremely good result was 10, the good result was 8, the slightly good result was 6, the slightly inferior result was 2, the inferior result was 2, and the extremely inferior result was 1.

(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 No.) 70% aqueous solution and N, N-dimethylaminopropylacrylamide methyl chloride quaternary salt 70% aqueous solution 4 parts were added into 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 mixture of 9 parts of styrene, 2 parts of diacetone acrylamide and 2 parts of 2-hydroxyethyl methacrylate was continuously added to 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, 290 parts of N-isopropylacrylamide, 10 parts of diacetone acrylamide, 0.5 part of methylenebisacrylamide, 5 parts of 70% aqueous solution of quaternary salt of N, N-dimethylaminopropylacrylamide methyl chloride, 10 parts of a 25% aqueous solution, 15 parts of a 25% aqueous solution of “Blemmer QA” (manufactured by NOF Corporation, cationic reactive surfactant: trade name) and 2,2′-azobis (2-methylpropionamidine) ) A solution in which 11 parts of a 5% dibasic acid solution was dissolved was added to the reaction vessel, and the addition was completed over 5 hours. The liquid temperature in the reaction vessel was kept at 80 ° C. during the addition and 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 into the reaction vessel. After completion of the addition of the ethanol aqueous solution, the polymer compound 1 having an emulsion having a resin solid content of 11% and a number average particle size of 100 nm was obtained by cooling to room temperature. The temperature point was measured and found to be 30 ° C.

(Preparation Example 2)
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, 21 parts of a 38% aqueous solution of “Eleminol JS-2” and 12 parts of “ADEKA rear soap SE-1025N” (25% aqueous solution) were added to the reactor. Further, 8 parts of a 2% aqueous solution of ammonium persulfate was put into the reactor, and after 5 minutes, 9 parts of methyl methacrylate, 9 parts of butyl acrylate, 9 parts of styrene, 2 parts of diacetone acrylamide and 2 parts of acrylic acid were added. The mixed liquid 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, 290 parts of N-isopropylacrylamide, 10 parts of diacetone acrylamide, 0.5 parts of methylenebisacrylamide, 0.5 parts of acrylic acid, 3 parts of 38% aqueous solution of “Eleminol JS-2”, “Adekalia” Addition of 11 parts of "SOPE SE-1025N" (25% aqueous solution) and 46 parts of 2% aqueous solution of ammonium persulfate into the reaction vessel was started, and the addition was completed over 5 hours. The liquid temperature in the reaction vessel was kept at 80 ° C. during the addition and 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 into the reaction vessel. It cooled to room temperature after completion | finish of addition of ethanol aqueous solution. Thereafter, the pH of the emulsion was adjusted to 9 with 5% aqueous ammonia to obtain a polymer compound 2 in which an emulsion having a resin solid content of 11% and a number average particle size of 100 nm was formed. The temperature point was measured and found to be 30 ° 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. Polymer compound 3 having an emulsion with 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.

[Example 1]
Water is added to dry silica (manufactured by Nippon Aerosil Co., Ltd., A300: trade name, hereinafter referred to as A300) to a solid content of 18% by mass and dispersed using an ultrasonic disperser. A polymer (Asahi Denka Kogyo Co., Ltd., Adeka thioace DM-20A: trade name) 20% by mass aqueous solution was added so that the dry silica / cationic polymer = 100/5 (dry mass ratio), and then again super Dispersion liquid 1 was obtained by dispersing using a sonic disperser.
Boric acid and borax were added to and mixed with dispersion 1 at a ratio of A300 / boric acid / borax = 100/3 / 0.5 (dry mass ratio), and then heated to 50 ° C. to obtain PVA203 (( Kuraray Polyvinyl Alcohol, Kuraray Poval PVA203: trade name) 10% aqueous solution and PVA235 (Kuraray Co., Ltd., Kuraray Povar PVA235: trade name) 5% aqueous solution, A300 / PVA203 / PVA235 = 100/1 / It added and mixed in the ratio used as 18 (dry mass ratio), and the coating liquid 1 was created.
On the other hand, the polymer compound 1 obtained in Preparation Example 1 on colloidal silica (number average particle size 10 nm, manufactured by Nissan Kogyo Co., Ltd., Snowtex AK: trade name, hereinafter referred to as AK) is expressed as AK / polymer. A coating liquid 2 was prepared by adding and mixing at 50 ° C. in a ratio of Compound 1 = 100/30 (dry mass ratio).
Using a base paper of 100 g / m ² as the support, the coating liquid 1 and the coating liquid 2 are combined with a die coater so that the coating liquid 1 is on the support and the coating liquid 2 is on the coating liquid 1. After simultaneously using the film, the film was pressure-bonded to a mirror surface roll having a surface temperature of 85 ° C., dried, and peeled to obtain a recording paper. The coating liquid 1 was applied so that the dry weight was 18 g / m ² , and the coating liquid 2 was applied so that the dry weight was 2 g / m ² . However, immediately before pressure bonding to the mirror surface roll, a 0.5% solution of the release agent (Knop Coat SYC) was placed on the coating layer, and the release agent other than being caught at the interface between the mirror surface roll and the coating layer was recovered. The evaluation results of this recording paper are shown in Table 1.

[Example 2]
The polymer compound 1 obtained in Preparation Example 1 was added to the dispersion liquid 1 at a rate of A300 / polymer compound 1 = 100/25 (dry mass ratio) at 50 ° C. and mixed to obtain a coating liquid 3. Created.
Using a base paper of 100 g / m ² as a support, the coating liquid 3 and the coating liquid 2 are formed into a die coater so that the coating liquid 3 is formed on the support and the coating liquid 2 is formed on the coating liquid 3. The film was simultaneously coated using a film, pressed onto a mirror roll having a surface temperature of 85 ° C., dried, and peeled to obtain a recording paper. The coating liquid 3 was applied so that the dry weight was 18 g / m ² , and the coating liquid 2 was applied so that the dry weight was 2 g / m ² . However, immediately before pressure bonding to the mirror surface roll, a 0.5% solution of the release agent (Knop Coat SYC) was placed on the coating layer, and the release agent other than being caught at the interface between the mirror surface roll and the coating layer was recovered. The evaluation results of this recording paper are shown in Table 1.
[Example 3]
The polymer compound 2 obtained in Preparation Example 2 on colloidal silica (number average particle size 10 nm, manufactured by Nissan Kogyo Co., Ltd., Snowtex C: trade name, hereinafter referred to as STC) is referred to as STC / polymer compound 2 = A coating liquid 4 was prepared by adding and mixing at 50 ° C. at a ratio of 100/30 (dry mass ratio). Using a base paper of 100 g / m ² as a support, the coating liquid 3 and the coating liquid 4 are formed into a die coater so that the coating liquid 3 is formed on the support and the coating liquid 4 is formed on the coating liquid 3. The film was simultaneously coated using a film, pressed onto a mirror roll having a surface temperature of 85 ° C., dried, and peeled to obtain a recording paper. The coating liquid 3 was applied so that the dry weight was 18 g / m ² , and the coating liquid 4 was applied so that the dry weight was 2 g / m ² . However, immediately before pressure bonding to the mirror surface roll, a 0.5% solution of the release agent (Knop Coat SYC) was placed on the coating layer, and the release agent other than being caught at the interface between the mirror surface roll and the coating layer was recovered. The evaluation results of this recording paper are shown in Table 1.

[Comparative Example 1]
Using a base paper of 100 g / m ² as a support, after coating the coating liquid 1 on the support using a die coater, it is pressure-bonded to a mirror roll having a surface temperature of 85 ° C., dried, and peeled off. A record sheet was obtained. The coating liquid 1 was applied so that the dry weight was 18 g / m ² . However, immediately before pressure bonding to the mirror surface roll, a 0.5% solution of the release agent (Knop Coat SYC) was placed on the coating layer, and the release agent other than being caught at the interface between the mirror surface roll and the coating layer was recovered. The evaluation results of this recording paper are shown in Table 1.
[Comparative Example 2]
Polymer compound 3 obtained in Preparation Example 3 on colloidal silica (number average particle size 10 nm, manufactured by Nissan Kogyo Co., Ltd., Snowtex AK: trade name, hereinafter referred to as AK) is expressed as AK / polymer compound 3 = A coating liquid 5 was prepared by adding and mixing at 50 ° C. at a ratio of 100/30 (dry mass ratio).
A base paper of 100 g / m ² is used as a support, and the coating liquid 1 and the coating liquid 5 are die coater so that the coating liquid 1 is formed on the support and the coating liquid 5 is formed on the coating liquid 1. The film was simultaneously coated using a film, pressed onto a mirror roll having a surface temperature of 85 ° C., dried, and peeled to obtain a recording paper. The coating liquid 1 was applied so that the dry weight was 18 g / m ² , and the coating liquid 5 was applied so that the dry weight was 2 g / m ² . However, immediately before pressure bonding to the mirror surface roll, a 0.5% solution of the release agent (Knop Coat SYC) was placed on the coating layer, and the release agent other than being caught at the interface between the mirror surface roll and the coating layer was recovered. The evaluation results of this recording paper are shown in Table 1.

  By using the present invention, the surface gloss is higher than the conventional one using a paper, sheet, film, cloth or the like used as a support for various printing methods performed by a method of attaching an ink composition to a recording medium. In addition, it is possible to provide an inkjet recording medium having superior surface gloss, image quality, and ink absorptivity compared to conventional recording media.

Claims (4)

  A recording layer is provided on at least one surface of the support, and on the recording layer, a polymer compound which exhibits hydrophilicity in a temperature region below the temperature sensitive point and exhibits hydrophobicity in a temperature region exceeding the temperature sensitive point ( A recording paper provided with a gloss layer containing A) and fine particles (B).   It is obtained by a process comprising applying the gloss layer on the recording layer and pressing the gloss layer to a heated mirror roll while the coated gloss layer is in a wet state. The recording paper according to claim 1.   The recording paper according to claim 1, wherein the recording paper is an inkjet recording medium.   It is a coating liquid used for glossy layer coating of the recording paper as described in any one of Claims 1-3, Comprising: The said high molecular compound (A) forms the emulsion in this coating liquid. The said coating liquid characterized.