JP4575889B2 - Thermal transfer image-receiving sheet - Google Patents

Description

  The present invention relates to a heat-sensitive transfer image-receiving sheet, and more particularly to a heat-sensitive transfer image-receiving sheet for providing a good image having a high transfer density and less image unevenness due to equipment contamination.

  Conventionally, various thermal transfer recording methods are known, and among them, the dye diffusion transfer recording method is attracting attention as a process capable of producing a color hard copy closest to the image quality of a silver salt photograph (for example, Non-Patent Document 1 and 2). In addition, it has the advantages of being dry, being able to visualize directly from digital data, and being easy to duplicate, compared to silver salt photography.

  In this dye diffusion transfer recording system, a thermal transfer sheet containing a pigment (hereinafter also referred to as an ink sheet) and a thermal transfer image receiving sheet (hereinafter also referred to as an image receiving sheet) are superposed, and then heat is generated by an electrical signal. By heating the ink sheet with a controlled thermal head, the dye in the ink sheet is transferred to the image receiving sheet to record image information. By recording three colors of cyan, magenta, and yellow in an overlapping manner, A color image having a continuous change in color shading can be transferred and recorded.

In this type of image receiving sheet, a receiving layer for transferring the transferred dye is formed on the support, and in general, in order to improve the adhesion between the image receiving sheet and the transfer sheet, A layer having high cushioning properties such as a foamed layer made of a resin and a foaming agent or a porous layer containing a hollow polymer is formed between the layers (see, for example, Patent Document 1 or 2).
In Patent Document 1, an intermediate layer mainly composed of hollow particles and an organic solvent-resistant polymer is formed on a support by coating and drying, and then the receiving layer is coated with an organic solvent-based resin coating solution. Is disclosed. However, there is a problem that the sensitivity is insufficient and the cost is high. In addition, when a large number of images are output, there is a problem that image defects occur due to contamination of the platen roller and the thermal head in the apparatus due to white powder-like contaminants that may be caused by the image receiving paper.
The thermal transfer image-receiving sheet described in Patent Document 2 is disclosed to include a layer in which hollow spherical pigments are dispersed and an image-receiving layer (receiving layer). However, there is a problem that bleeding occurs in an image after image transfer. there were.
Japanese Patent Laid-Open No. 11-321128 JP-A-2-89690 “New development of information recording (hard copy) and its materials”, published by Toray Research Center, Inc., 1993, p. 241-285 “Development of Printer Materials”, issued by CMC Co., Ltd., 1995, p. 180

  SUMMARY OF THE INVENTION An object of the present invention is to provide a thermal transfer image-receiving sheet having a high transfer density and few image defects due to contamination inside the apparatus at a low cost.

As a result of intensive studies, the inventors of the present invention have, on the support, a base layer, a heat insulating layer containing a non-foamed hollow polymer having a particle size of 0.1 to 2 μm and formed of styrene-acrylic resin, and Adhesive for providing a polyethylene resin layer on a support in a heat-sensitive transfer image-receiving sheet having at least one receptor layer comprising a polymer latex of a copolymer of vinyl chloride and alkyl acrylate and a microcrystalline wax as a release agent It has been found that the above-mentioned problems can be solved by not using.

(1) The support has at least one receiving layer containing a polymer latex of a copolymer of vinyl chloride and alkyl acrylate and a microcrystalline wax as a release agent , and the receiving layer and the support A thermal transfer image-receiving sheet having at least one heat-insulating layer containing a non-foamed hollow polymer latex having a particle size of 0.1 to 2 μm and formed of styrene-acrylic resin, Between the heat-insulating layer and the support, there is a base layer in contact with the heat-insulating layer, and all layers including the base layer and above the base layer contain latex, and the support is on both sides of the base paper. A heat-sensitive transfer image-receiving sheet, which is a support provided with a polyethylene resin layer without using an adhesive.
(2) The support has at least one receiving layer containing a polymer latex of a copolymer of vinyl chloride and alkyl acrylate and a microcrystalline wax as a release agent , and the receiving layer and the support A thermal transfer image-receiving sheet having at least one heat-insulating layer containing a non-foamed hollow polymer latex having a particle size of 0.1 to 2 μm and formed of styrene-acrylic resin, Between the heat-insulating layer and the support, there is a base layer in contact with the heat-insulating layer, and all layers including the base layer and above the base layer contain latex, and the support is on both sides of the base paper. A heat-sensitive transfer image-receiving sheet, which is a support having a polyethylene resin layer without an adhesive and having at least two polyethylene resin layers on the receiving layer side.
(3) The heat-sensitive transfer image-receiving sheet as described in (1), which has at least two polyethylene resin layers on both surfaces of the support.
(4) The sensation according to any one of (1) to (3), wherein the polyethylene resin opposite to the receiving layer on the support is a blend of high-density polyethylene and low-density polyethylene. Thermal transfer image receiving sheet.
(5) The thermal transfer image-receiving sheet according to any one of (1) to (4), wherein the polyethylene resin on the receiving layer side on the support is a blend of high-density polyethylene and low-density polyethylene. .
(6) The feeling according to any one of (1) to (5), wherein the base layer, the heat insulating layer, and the receiving layer on the polyethylene resin layer are formed by simultaneous multilayer coating. Thermal transfer image receiving sheet.
(7) The heat-sensitive transfer image-receiving sheet as described in any one of (1) to (6), wherein the heat-insulating layer contains a water-soluble polymer.
(8) The heat-sensitive transfer image-receiving sheet as described in any one of (1) to (6), wherein the heat-insulating layer contains gelatin.
(9) The feeling according to any one of (1) to (8), wherein the heat insulation layer contains the hollow polymer latex and a binder resin, and the binder resin is only a water-soluble polymer. Thermal transfer image receiving sheet.
(10) The thermal transfer image receiving image as described in any one of (1) to (8), wherein the heat insulating layer contains the hollow polymer latex and a binder resin, and the binder resin is only gelatin. Sheet.
(11) The heat-sensitive transfer image-receiving sheet as described in any one of (1) to (10), wherein the receiving layer contains gelatin.
(1 2 ) The heat-sensitive transfer image-receiving sheet according to any one of (1) to (1 1 ), wherein the receiving layer contains an image fastening agent or an ultraviolet absorber.
(1 3 ) The heat-sensitive transfer image-receiving sheet according to any one of (1) to (1 2 ), wherein the heat-insulating layer contains an image fastening agent or an ultraviolet absorber.
(1 4 ) The heat-sensitive transfer image-receiving sheet according to any one of (1) to (1 1 ), wherein the receptor layer contains an emulsion containing an image fastening agent or an ultraviolet absorber.
(1 5) The heat-sensitive transfer image-receiving sheet according to any one of the heat insulating layer, characterized in that it contains an emulsion containing an image fastness agent or UV absorber in (1) - (1 2).

  The heat-sensitive transfer image-receiving sheet of the present invention has a high transfer density, has few image defects due to contamination inside the device, and is low in cost.

Hereinafter, the present invention will be described in detail.
The thermal transfer image-receiving sheet of the present invention has at least one dye-receiving layer (receiving layer) on a support, and has at least one heat-insulating layer (porous layer) between the support and the receiving layer. And it has a base layer in contact with this heat insulation layer between a support body and a heat insulation layer . Further, between the support and the heat-insulating layer, a white background controlling layer, a charge controlling layer, an adhesive layer may be etc. primer layer formation.
The receiving layer and the heat insulating layer are preferably formed by simultaneous multilayer coating. When the underlayer is included, the receiving layer, the underlayer and the heat insulating layer can be formed by simultaneous multilayer coating.

(Receptive layer)
The receiving layer serves to receive the dye transferred from the ink sheet and maintain the formed image. In the image receiving sheet of the present invention, the receiving layer contains a polymer latex. The receiving layer may be one layer or two or more layers. Moreover, it is preferable that a receiving layer contains the water-soluble polymer mentioned later.

<Polymer latex>
The polymer latex used in the present invention will be described. In the heat-sensitive transfer image-receiving sheet of the present invention, the polymer latex that can be used in the receptor layer is a water-insoluble hydrophobic polymer dispersed as fine particles in a water-soluble dispersion medium. As the dispersion state, the polymer is emulsified in a dispersion medium, the emulsion is polymerized, the micelle is dispersed, or the polymer molecule has a partially hydrophilic structure and the molecular chain itself is molecularly dispersed. Anything may be used. For polymer latex, Tadashi Okuda, Hiroshi Inagaki, “Synthetic Resin Emulsion”, published by Kobunshi Publishing (1978), Takaaki Sugimura, Ikuo Kataoka, Junichi Suzuki, Keiji Kasahara, “Application of Synthetic Latex”, Takashi Published by Molecular Publications (1993), Soichi Muroi, “Synthetic Latex Chemistry”, published by High Polymers Publications (1970), supervised by Yoshiaki Mitsuzawa, “Development and application of water-based coating materials”, CMC Publishing ( 2004) and Japanese Patent Application Laid-Open No. 64-538. The average particle size of the dispersed particles is preferably in the range of 1 to 50000 nm, more preferably about 5 to 1000 nm.
The particle size distribution of the dispersed particles is not particularly limited, and may have a wide particle size distribution or a monodispersed particle size distribution.

  The polymer latex may be a so-called core / shell type latex in addition to a normal uniform polymer latex. In this case, it may be preferable to change the glass transition temperature between the core and the shell. The glass transition temperature of the polymer latex of the present invention is preferably -30 ° C to 100 ° C, more preferably 0 ° C to 80 ° C, further preferably 10 ° C to 70 ° C, and particularly preferably 15 ° C to 60 ° C.

Preferred embodiments of the polymer latex used in the present invention include acrylic polymers, polyesters, rubbers (for example, SBR resin), polyurethanes, polyvinyl chlorides, polyvinyl acetates, polyvinylidene chlorides, polyolefins and the like. A hydrophobic polymer can be preferably used. These polymers may be linear polymers, branched polymers, crosslinked polymers, so-called homopolymers obtained by polymerizing a single monomer, or copolymers obtained by polymerizing two or more types of monomers. In the case of a copolymer, it may be a random copolymer or a block copolymer. These polymers have a number average molecular weight of 5,000 to 100,000, preferably 10,000 to 500,000. If the molecular weight is too small, the mechanical strength of the layer containing the latex is insufficient, and if it is too large, the film formability is poor and this is not preferred. A crosslinkable polymer latex is also preferably used.
In the present invention, a polymer latex of a copolymer of vinyl chloride and alkyl acrylate is used.

The monomer used for the synthesis of the polymer latex used in the present invention is not particularly limited, and monomers that can be polymerized by a normal radical polymerization or ionic polymerization method are preferably the following monomer groups (a) to (j). Can be used. Polymer monomers can be synthesized by selecting these monomers independently and freely in combination.
However, among the following monomers, vinyl chloride and alkyl acrylate are used for the polymer latex of the copolymer of vinyl chloride and alkyl acrylate used in the present invention.

-Monomer group (a)-(j)-
(A) Conjugated dienes: 1,3-pentadiene, isoprene, 1-phenyl-1,3-butadiene, 1-α-naphthyl-1,3-butadiene, 1-β-naphthyl-1,3-butadiene, cyclo Pentadiene and the like.
(B) Olefins: ethylene, propylene, vinyl chloride, vinylidene chloride, 6-hydroxy-1-hexene, 4-pentenoic acid, methyl 8-nonenoate, vinylsulfonic acid, trimethylvinylsilane, trimethoxyvinylsilane, 1,4- Divinylcyclohexane, 1,2,5-trivinylcyclohexane, etc.

  (C) α, β-unsaturated carboxylic acid esters: alkyl acrylate (eg, methyl acrylate, ethyl acrylate, butyl acrylate, cyclohexyl acrylate, 2-ethylhexyl acrylate, dodecyl acrylate, etc.), substituted alkyl acrylate (eg, 2-chloro Ethyl acrylate, benzyl acrylate, 2-cyanoethyl acrylate, etc.), alkyl methacrylate (eg, methyl methacrylate, butyl methacrylate, 2-ethylhexyl methacrylate, dodecyl methacrylate, etc.), substituted alkyl methacrylate (eg, 2-hydroxyethyl methacrylate, glycidyl methacrylate) Glycerin monomethacrylate, 2-acetoxyethyl methacrylate, tetrahydrofurfurylme Chryrate, 2-methoxyethyl methacrylate, polypropylene glycol monomethacrylate (polyoxypropylene added mole number = 2 to 100), 3-N, N-dimethylaminopropyl methacrylate, chloro-3-N, N, N-trimethyl Ammoniopropyl methacrylate, 2-carboxyethyl methacrylate, 3-sulfopropyl methacrylate, 4-oxysulfobutyl methacrylate, 3-trimethoxysilylpropyl methacrylate, allyl methacrylate, 2-isocyanatoethyl methacrylate, etc.), unsaturated dicarboxylic acid derivatives (Eg, monobutyl maleate, dimethyl maleate, monomethyl itaconate, dibutyl itaconate, etc.), polyfunctional esters (eg, ethylene glycol diacrylate) Ethylene glycol dimethacrylate, 1,4-cyclohexanediacrylate, pentaerythritol tetramethacrylate, pentaerythritol triacrylate, trimethylolpropane triacrylate, trimethylolethane triacrylate, dipentaerythritol pentamethacrylate, pentaerythritol hexaacrylate, 1,2, 4-cyclohexanetetramethacrylate and the like.

(D) Amides of α, β-unsaturated carboxylic acids: for example, acrylamide, methacrylamide, N-methylacrylamide, N, N-dimethylacrylamide, N-methyl-N-hydroxyethylmethacrylamide, N-tertbutylacrylamide, N-tert octyl methacrylamide, N-cyclohexyl acrylamide, N-phenyl acrylamide, N- (2-acetoacetoxyethyl) acrylamide, N-acryloylmorpholine, diacetone acrylamide, itaconic acid diamide, N-methylmaleimide, 2-acrylamide -Methylpropanesulfonic acid, methylenebisacrylamide, dimethacryloylpiperazine and the like .
(E) Unsaturated nitriles: acrylonitrile, methacrylonitrile and the like.
(F) Styrene and its derivatives: styrene, vinyl toluene, p-tertbutyl styrene, vinyl benzoic acid, methyl vinyl benzoate, α-methyl styrene, p-chloromethyl styrene, vinyl naphthalene, p-hydroxymethyl styrene, p- Styrene sulfonic acid sodium salt, p-styrene sulfinic acid potassium salt, p-aminomethylstyrene, 1,4-divinylbenzene and the like.
(G) Vinyl ethers: methyl vinyl ether, butyl vinyl ether, methoxyethyl vinyl ether, and the like.
(H) Vinyl esters: vinyl acetate, vinyl propionate, vinyl benzoate, vinyl salicylate, vinyl chloroacetate, and the like.
(I) α, β-unsaturated carboxylic acid and salts thereof: acrylic acid, methacrylic acid, itaconic acid, maleic acid, sodium acrylate, ammonium methacrylate, potassium itaconate and the like.
(J) Other polymerizable monomers: N-vinylimidazole, 4-vinylpyridine, N-vinylpyrrolidone, 2-vinyloxazoline, 2-isopropenyloxazoline, divinylsulfone, and the like.

  The polymer latex that can be used in the present invention is commercially available, and the following polymers can be used. Examples of acrylic polymers include Sebian A-4635, 4718, 4601 manufactured by Daicel Chemical Industries, Ltd., Nipol Lx811, 814, 821, 820, 855 (P-17: Tg36 ° C.) manufactured by Zeon Corporation, 857x2. (P-18: Tg43 ° C), Dainippon Ink Chemical Co., Ltd. Voncoat R3370 (P-19: Tg25 ° C), 4280 (P-20: Tg15 ° C), Nippon Pure Chemical Co., Ltd. Jurimer ET-410 ( P-21: Tg44 ° C), JSR AE116 (P-22: Tg50 ° C), AE119 (P-23: Tg55 ° C), AE121 (P-24: Tg58 ° C), AE125 (P-25: Tg60) ° C), AE134 (P-26: Tg48 ° C), AE137 (P-27: Tg48 ° C), AE140 (P-28: Tg53 ° C), AE173 (P-29: Tg60 ° C), Aaron manufactured by Toagosei Co., Ltd. A-104 (P-30: Tg45 ° C), NS-600X, NS-620X manufactured by Takamatsu Yushi Co., Ltd., Vinibrand 2580, 2583, 2641, 2770, 2770H, 2635, 2886, 5202C manufactured by Nissin Chemical Industry Co., Ltd. , 2706, etc. (all are trade names).

Examples of polyesters include FINETEX ES650, 611, 675, 850 manufactured by Dainippon Ink and Chemicals, WD-size, WMS manufactured by Eastman Chemical, A-110, A-115GE, A- 120, A-121, A-124GP, A-124S, A-160P, A-210, A-215GE, A-510, A-513E, A-515GE, A-520, A-610, A-613, A-615GE, A-620, WAC-10, WAC-15, WAC-17XC, WAC-20, S-110, S-110EA, S-111SL, S-120, S-140, S-140A, S- 250, S-252G, S-250S, S-320, S-680, DNS-63P, NS-122L
NS-122LX, NS-244LX, NS-140L, NS-141LX, NS-282LX, Aronmelt PES-1000 series, PES-2000 series, Toyobo Co., Ltd. 1200, MD-1220, MD-1245, MD-1250, MD-1335, MD-1400, MD-1480, MD-1500, MD-1930, MD-1985, Sumitomo Seika Co., Ltd. (Both are trade names).

  Examples of polyurethanes include Dainippon Ink Chemical Co., Ltd.HYDRAN AP10, AP20, AP30, AP40, 101H, Vondic 1320NS, 1610NS, Dainichi Seika Co., Ltd.D-1000, D-2000, D-6000, D-4000, D-9000, Takamatsu Yushi Co., Ltd. NS-155X, NS-310A, NS-310X, NS-311X, Daiichi Kogyo Seiyaku Co., Ltd. Elastron etc. (all are trade names).

  Examples of rubbers include LACSTAR 7310K, 3307B, 4700H, 7132C (above, manufactured by Dainippon Ink and Chemicals), Nipol Lx416, LX410, LX430, LX435, LX110, LX415A, LX438C, 2507H, LX303A, LX407BP series, V1004, MH5055 (made by Nippon Zeon Co., Ltd.), etc. (all are trade names).

  Examples of polyvinyl chlorides include: Z351, G351, G576, Nissin Chemical Industry Co., Ltd., Vinibrand 240, 270, 277, 375, 386, 609, 550, 601, 602, 630, 660, 671, 683, 680, 680S, 681N, 685R, 277, 380, 381, 410, 430, 432, 860, 863, 865, 867, 900, 900GT, 938, 950, etc. (all are trade names). Examples of polyvinylidene chlorides include L502 and L513 manufactured by Asahi Kasei Kogyo Co., Ltd., and D-5071 manufactured by Dainippon Ink & Chemicals, Inc. (all are trade names). Examples of polyolefins include Chemipearl S120, SA100, V300 (P-40: Tg80 ° C) manufactured by Mitsui Petrochemical Co., Ltd., Voncoat 2830, 2210, 2960 manufactured by Dainippon Ink Chemical Co., Ltd., Sumitomo Seika Co., Ltd. Examples of Zyxen, Sepoljon G, and copolymerized nylons include Sepoljon PA manufactured by Sumitomo Seika Co., Ltd. (all are trade names).

  Examples of polyvinyl acetates include Nishin Chemical Industry Co., Ltd.ViniBran 1080, 1082, 1085W, 1108W, 1108S, 1563M, 1566, 1570, 1588C, A22J7-F2, 1128C, 1137, 1138, A20J2, A23J1, A23J1, A23K1, A23P2E, A68J1N, 1086A, 1086, 1086D, 1108S, 1187, 1241LT, 1580N, 1083, 1571, 1572, 1581, 4465, 4466, 4468W, 4468S, 4470, 4485LL, 4495LL, 1023, 1042, 1060, 1060S, 1080M, 1084W, 1084S, 1096, 1570K, 1050, 1050S, 3290, 1017AD, 1002, 1006, 1008, 1107L, 1225, 1245L, GV-6170, GV-6181, 4468W, 4468S, etc. Product name).

  These polymer latexes may be used alone or in combination of two or more as required.

  In the present invention, the receptor layer is preferably prepared by applying an aqueous coating solution and then drying it. However, “aqueous” as used herein means that 60% by mass or more of the solvent (dispersion medium) of the coating solution is water. Components other than water in the coating solution include methyl alcohol, ethyl alcohol, isopropyl alcohol, methyl cellosolve, ethyl cellosolve, dimethylformamide, ethyl acetate, diacetone alcohol, furfuryl alcohol, benzyl alcohol, diethylene glycol monoethyl ether, oxyethyl phenyl ether A water miscible organic solvent such as can be used.

The minimum film forming temperature (MFT) of the polymer latex is preferably −30 ° C. to 90 ° C., more preferably about 0 ° C. to 70 ° C. A film-forming auxiliary may be added to control the minimum film-forming temperature. A film-forming aid, also called a temporary plasticizer, is an organic compound (usually an organic solvent) that lowers the minimum film-forming temperature of a polymer latex. )It is described in. Preferred film-forming aids are the following compounds, but the compounds that can be used in the present invention are not limited to the following specific examples.
Z-1: benzyl alcohol Z-2: 2,2,4-trimethylpentanediol-1,3-monoisobutyrate Z-3: 2-dimethylaminoethanol Z-4: diethylene glycol

  Preferable examples of the polymer latex used in the present invention include polylactic acid esters, polyurethanes, polycarbonates, polyesters, polyacetals, SBRs, and polyvinyl chlorides. Among these, polyesters and polycarbonates Most preferably, polyvinyl chlorides are included.

  As the polymer latex used in the present invention, any polymer may be used in combination with the polymer latex. The polymer that can be used in combination is preferably transparent or translucent and colorless. Natural resins, polymers and copolymers, synthetic resins, polymers and copolymers, and other media for forming films such as gelatins and polyvinyl alcohol , Hydroxyethylcelluloses, cellulose acetates, cellulose acetate butyrate, polyvinylpyrrolidones, casein, starch, polyacrylic acids, polymethylmethacrylic acids, polyvinylchlorides, polymethacrylic acids, styrene-maleic anhydride copolymers , Styrene-acrylonitrile copolymers, styrene-butadiene copolymers, polyvinyl acetals (eg, polyvinyl formal and polyvinyl butyral), polyesters, polyurethanes, phenoxy Fat, polyvinylidene chlorides, polyepoxides, polycarbonates, polyvinyl acetates, polyolefins, and polyamides. The binder may be coated from water or an organic solvent or emulsion.

  The binder used in the present invention preferably has a glass transition temperature (Tg) in the range of −30 ° C. to 70 ° C., more preferably in the range of −10 ° C. to 50 ° C. in view of processing brittleness and image storage stability. Preferably it is the range of 0 degreeC-40 degreeC. It is also possible to use a blend of two or more polymers as the binder, and in this case, it is preferable that the weighted average Tg in consideration of the composition falls within the above range. Moreover, when phase-separating or having a core-shell structure, the weighted average Tg is preferably within the above range.

This glass transition temperature (Tg) can be calculated by the following formula.
1 / Tg = Σ (Xi / Tgi)
Here, it is assumed that n monomer components from i = 1 to n are copolymerized in the polymer. Xi is the mass fraction of the i-th monomer (ΣXi = 1), and Tgi is the glass transition temperature (absolute temperature) of the homopolymer of the i-th monomer. However, Σ is the sum from i = 1 to n. In addition, the value of the homopolymer glass transition temperature (Tgi) of each monomer can adopt the value of “Polymer Handbook (3rd Edition)” (J. Brandrup, EHImmergut (Wiley-Interscience, 1989)).

  The polymer used for the binder used in the present invention can be easily obtained by solution polymerization method, suspension polymerization method, emulsion polymerization method, dispersion polymerization method, anionic polymerization method, cationic polymerization, etc., but the emulsion obtained as latex A polymerization method is most preferred. Also preferred is a method of preparing a polymer in a solution and neutralizing or adding an emulsifier and then adding water and forcibly stirring to prepare an aqueous dispersion. In the emulsion polymerization method, for example, water or a mixed solvent of water and an organic solvent miscible with water (for example, methanol, ethanol, acetone, etc.) is used as a dispersion medium, and the monomer is 5 to 150% by mass with respect to the dispersion medium. Using the mixture and the total amount of monomers, an emulsifier and a polymerization initiator are used, and polymerization is carried out with stirring at about 30 to 100 ° C., preferably 60 to 90 ° C. for 3 to 24 hours. Various conditions such as the dispersion medium, the monomer concentration, the initiator amount, the emulsifier amount, the dispersant amount, the reaction temperature, and the monomer addition method are appropriately set in consideration of the type of monomer used. Moreover, it is preferable to use a dispersing agent as needed.

  The emulsion polymerization method can be generally performed according to the following literature. Tadashi Okuda, Hiroshi Inagaki, "Synthetic Resin Emulsion", published by Polymer Publishing Association (1978), Takaaki Sugimura, Akio Kataoka, Junichi Suzuki, Keiji Kasahara, "Application of Synthetic Latex", Published by Polymer Publishing Society (1993) 1), Soichi Muroi, “Chemistry of Synthetic Latex”, published by Kobunshi Shuppankai (1970). In the emulsion polymerization method for synthesizing the polymer latex used in the present invention, a batch polymerization method, a monomer (continuous / divided) addition method, an emulsion addition method, a seed polymerization method, etc. can be selected from the viewpoint of latex productivity. A batch polymerization method, a monomer (continuous / divided) addition method, and an emulsion addition method are preferred.

The polymerization initiator only needs to have radical generating ability, such as inorganic peroxides such as persulfate and hydrogen peroxide, peroxides described in Nippon Oil & Fats Co., Ltd. organic peroxide catalog, and Wako Pure Chemical Industries, Ltd. The azo compounds described in the azo polymerization initiator catalog can be used. Among these, water-soluble peroxides such as persulfate and water-soluble azo compounds described in the Wako Pure Chemical Industries, Ltd. Azo Polymerization Initiator Catalog are preferable. Ammonium persulfate, sodium persulfate, potassium persulfate, azobis ( 2-methylpropionamidine) hydrochloride, azobis (2-methyl-N- (2-hydroxyethyl) propionamide), azobiscyanovaleric acid is more preferable, and in particular, peroxidation such as ammonium persulfate, sodium persulfate, potassium persulfate and the like. The product is preferable from the viewpoint of image preservability, solubility, and cost.

  As the addition amount of the polymerization initiator, the polymerization initiator is preferably 0.3% by mass to 2.0% by mass, and 0.4% by mass to 1.75% by mass with respect to the total amount of monomers. Is more preferable, and 0.5% by mass to 1.5% by mass is particularly preferable.

  As the polymerization emulsifier, any of an anionic surfactant, a nonionic surfactant, a cationic surfactant, and an amphoteric surfactant can be used, but the anionic surfactant has dispersibility and image storability. From the viewpoint, it is preferable to use a sulfonic acid type anionic surfactant because polymerization stability can be secured in a small amount and resistance to hydrolysis, and a long chain represented by Perex SS-H (trade name, Kao Corp.). Alkyl diphenyl ether disulfonate is more preferable, and a low electrolyte type such as Pionine A-43-S (trade name, Takemoto Yushi Co., Ltd.) is particularly preferable.

  As the polymerization emulsifier, a sulfonic acid type anionic surfactant is preferably used in an amount of 0.1% by mass to 10.0% by mass with respect to the total amount of monomers, and 0.2% by mass to 7.5% by mass is used. It is more preferable that 0.3% by mass to 5.0% by mass is used.

  In the synthesis of the polymer latex used in the present invention, it is preferable to use a chelating agent. A chelating agent is a compound capable of coordinating (chelating) multivalent ions such as metal ions such as iron ions and alkaline earth metal ions such as calcium ions. Japanese Patent Publication No. 6-8956, US Pat. No. 5,053,322 JP-A-4-73645, JP-A-4-127145, JP-A-4-47073, JP-A-4-305572, JP-A-6-11805, JP-A-5-173312, JP-A-5-66527 JP-A-5-158195, JP-A-6-118580, JP-A-6-110168, JP-A-6-161054, JP-A-6-175299, JP-A-6-214352, JP-A-7-114161, JP-A-7-114154, JP-A-7-120894, JP-A-7-199433, JP-A-7-306504, JP-A-9-43792, JP-A-8-314090, JP-A-10-182571, Special The compounds described in the publications or specifications of Kaihei 10-182570 and JP-A-11-190892 can be used.

  Examples of the chelating agent include inorganic chelate compounds (sodium tripolyphosphate, sodium hexametaphosphate, sodium tetrapolyphosphate, etc.), aminopolycarboxylic acid chelate compounds (nitrilotritriacetic acid, ethylenediaminetetraacetic acid, etc.), organic phosphonic acid chelate compounds ( Research Disclosure 18170, JP-A-52-102726, 53-42730, 56-97347, 54-121127, 55-4024, 55-4025, 55-29883, 55 -126241, 55-65955, 55-65956, 57-179743, 54-61125, and West German Patent No. 1045373, or the like), a polyphenol chelating agent, Polyamine chelation Preferably such things, aminopolycarboxylic acid derivatives being particularly preferred.

Preferable examples of the aminopolycarboxylic acid derivatives include the compounds listed in the appendix of “EDTA (-Complexane Chemistry)” (Nanedo, 1977), and some of the carboxyl groups of these compounds are sodium or potassium. Alkali metal salts and ammonium salts such as may be substituted. Particularly preferred aminocarboxylic acid derivatives include iminodiacetic acid, N-methyliminodiacetic acid, N- (2-aminoethyl) iminodiacetic acid, N- (carbamoylmethyl) iminodiacetic acid, nitrilotriacetic acid, ethylenediamine-N, N '-Diacetic acid, ethylenediamine-N, N'-di-α-propionic acid, ethylenediamine-N, N'-di-β-propionic acid, N, N'-ethylene-bis (α-o-hydroxyphenyl) glycine N, N′-di (2-hydroxybenzyl)
Ethylenediamine-N, N'-diacetic acid, ethylenediamine-N, N'-diacetic acid-N, N'-diacethydroxamic acid, N-hydroxyethylethylenediamine-N, N ', N'-triacetic acid, ethylenediamine-N , N, N ′, N′-tetraacetic acid, 1,2-propylenediamine-N, N, N ′, N′-tetraacetic acid, d, l-2,3-diaminobutane-N, N, N ′, N'-tetraacetic acid, meso-2,3-diaminobutane-N, N, N ', N'-tetraacetic acid, 1-phenylethylenediamine-N, N, N', N'-tetraacetic acid, d, l- 1,2-diphenylethylenediamine-N, N, N ′, N′-tetraacetic acid, 1,4-diaminobutane-N, N, N ′, N′-tetraacetic acid, trans-cyclobutane-1,2-diamine- N, N, N ′, N′-tetraacetic acid, trans-cyclopentane-1,2-diamine-N, N, N ′, N′-tetraacetic acid, trans-cyclohexane-1,2-diamine-N, N , N ′, N′-tetraacetic acid, cis-cyclohexane-1,2-diamine-N, N, N ′, N′-tetraacetic acid, sic Hexane-1,3-diamine-N, N, N ′, N′-tetraacetic acid, cyclohexane-1,4-diamine-N, N, N ′, N′-tetraacetic acid, o-phenylenediamine-N, N , N ′, N′-tetraacetic acid, cis-1,4-diaminobutene-N, N, N ′, N′-tetraacetic acid, trans-1,4-diaminobutene-N, N, N ′, N ′ -Tetraacetic acid, α, α'-diamino-o-xylene-N, N, N ', N'-tetraacetic acid, 2-hydroxy-1,3-propanediamine-N, N, N', N'-tetra Acetic acid, 2,2′-oxy-bis (ethyliminodiacetic acid), 2,2′-ethylenedioxy-bis (ethyliminodiacetic acid), ethylenediamine-N, N′-diacetic acid-N, N′-di-α -Propionic acid, ethylenediamine-N, N'-diacetic acid-N, N'-di-β-propionic acid, ethylenediamine-N, N, N ', N'-tetrapropionic acid, diethylenetriamine-N, N, N' , N '', N ''-pentaacetic acid, triethylenetetramine-N, N, N ', N'',N''', N '''-hexaacetic acid, 1,2,3 Triaminopropane-N, N, N ', N'',N''', N '''-hexaacetic acid, and some of the carboxyl groups of these compounds are alkali metal salts such as sodium and potassium. The substituted ones such as ammonium salts can also be mentioned.

  The addition amount of the chelating agent is preferably 0.01% by mass to 0.4% by mass, more preferably 0.02% by mass to 0.3% by mass with respect to the total amount of monomers. It is especially preferable that it is 03 mass%-0.15 mass%. When the amount of the chelating agent is less than 0.01% by mass, capture of metal ions mixed in the production process of the polymer latex becomes insufficient, stability against aggregation of the latex is lowered, and applicability is deteriorated. On the other hand, if it exceeds 0.4%, the viscosity of the latex increases and the coatability is lowered.

  A chain transfer agent is preferably used for the synthesis of the polymer latex used in the present invention. As the chain transfer agent, those described in “Polymer Handbook, 3rd edition” (Wiley-Interscience, 1989) are preferable. Sulfur compounds are more preferred because they have high chain transfer ability and can be used in small amounts. Hydrophobic mercaptan-based chain transfer agents such as tert-dodecyl mercaptan and n-dodecyl mercaptan are particularly preferred.

  The amount of the chain transfer agent is preferably 0.2% by mass to 2.0% by mass, more preferably 0.3% by mass to 1.8% by mass, and 0.4% by mass to 1.6% by mass with respect to the total amount of monomers. Mass% is particularly preferred.

  In emulsion polymerization, in addition to the above compounds, electrolytes, stabilizers, thickeners, antifoaming agents, antioxidants, vulcanizing agents, antifreezing agents, gelling agents, vulcanization accelerators, etc. are described in synthetic rubber handbooks, etc. These additives may be used.

  In the polymer latex used in the present invention, an aqueous solvent can be used as a solvent in the coating solution, but a water-miscible organic solvent may be used in combination. Examples of the water-miscible organic solvent include alcohols such as methyl alcohol, ethyl alcohol and propyl alcohol, cellosolves such as methyl cellosolve, ethyl cellosolve and butyl cellosolve, ethyl acetate and dimethylformamide. The amount of these organic solvents added is preferably 50% by mass or less, more preferably 30% by mass or less of the solvent.

The polymer latex used in the present invention preferably has a polymer concentration of 10 to 70% by mass, more preferably 20 to 60% by mass, and particularly preferably 30 to 55% by mass with respect to the latex liquid.
In addition, the polymer latex in the image receiving sheet of the present invention includes a gel or a dried film state formed by drying a part of the solvent after coating.

<Water-soluble polymer>
The receiving layer preferably contains a water-soluble polymer. Water-soluble polymers that can be used in the present invention include natural polymers (polysaccharides, microorganisms, animals), semi-synthetic polymers (cellulose, starch, alginic acid), and synthetic polymers (vinyl, Others), synthetic polymers such as polyvinyl alcohol described below, and natural or semi-synthetic polymers made from plant-derived cellulose or the like correspond to water-soluble polymers that can be used in the present invention. The water-soluble polymer in the present invention does not include the polymer latex.

Of the water-soluble polymers that can be used in the present invention, natural polymers and semi-synthetic polymers will be described in detail. Plant polysaccharides include gum arabic, κ-carrageenan, ι-carrageenan, λ-carrageenan, guar gum (such as Supercol from Squall), locust bean gum, pectin, tragacanth, corn starch (Purity- from National Starch & Chemical Co.) 21), phosphorylated starch (National Starch & Chemical Co. National 78-1898, etc.) and other microbial polysaccharides such as xanthan gum (Kelco Keltrol T), dextrin (National Starch & Chemical Co. Nadex360, etc.) Examples of animal natural polymers include gelatin (such as Crodyne B419 from Croda), casein, sodium chondroitin sulfate (such as Cromoist CS from Croda), and the like (all are trade names). Cellulose systems include ethyl cellulose (ICI Cellofas WLD, etc.), carboxymethyl cellulose (Daicel CMC, etc.), hydroxyethyl cellulose (Daicel HEC, etc.), hydroxypropyl cellulose (Aqualon Klucel, etc.), methyl cellulose (Henkel Viscontran, etc.), Examples include nitrocellulose (such as Isopropyl Wet from Hercules) and cationized cellulose (such as Crodacel QM from Croda). Other starches such as phosphorylated starch (National Starch &Chemical's National 78-1898) and alginic acid are sodium alginate (such as Kelco's Keltone) and propylene glycol alginate. Hi-care1000, etc.) and sodium hyaluronate (Hyalure, etc. from Lifecare Biomedial) are included (all are trade names).

  Of the water-soluble polymers that can be used in the present invention, synthetic polymers will be described in detail. Examples of the acrylic system include sodium polyacrylate, polyacrylic acid copolymer, polyacrylamide, polyacrylamide copolymer, polydiethylaminoethyl (meth) acrylate quaternary salt or a copolymer thereof, and the vinyl system includes polyvinylpyrrolidone, Polyvinyl pyrrolidone copolymer, polyvinyl alcohol, etc. include polyethylene glycol, polypropylene glycol, polyisopropyl acrylamide, polymethyl vinyl ether, polyethylene imine, polystyrene sulfonic acid or copolymer thereof, naphthalene sulfonic acid condensate salt, polyvinyl sulfonic acid Or a copolymer thereof, polyacrylic acid or a copolymer thereof, acrylic acid or a copolymer thereof, a maleic acid copolymer, a maleic acid monoester copolymer, an acryloylme Propane sulfonic acid or its copolymer, etc.), polydimethyldiallylammonium chloride or its copolymer, polyamidine or its copolymer, polyimidazoline, dicyanciamide condensate, epichlorohydrin-dimethylamine condensate, polyacrylamide Hoffman Decomposed product, water-soluble polyester (Plus coat Z-221, Z-446, Z-561, Z-450, Z-565, Z-850, Z-3308, RZ-105, RZ-570, manufactured by Kyodo Chemical Co., Ltd.) , Z-730, RZ-142 (both are trade names)).

Further, it has a superabsorbent polymer described in US Pat. No. 4,960,681, JP-A-62-245260, etc., that is, —COOM or —SO ₃ M (M is a hydrogen atom or an alkali metal). A homopolymer of vinyl monomers or a copolymer of these vinyl monomers or other vinyl monomers (for example, sodium methacrylate, ammonium methacrylate, Sumikagel L-5H (trade name) manufactured by Sumitomo Chemical Co., Ltd.) should also be used. Can do.

  Of the water-soluble synthetic polymers that can be used in the present invention, polyvinyl alcohol will be described in more detail. As a complete saponified product, PVA-105 [polyvinyl alcohol (PVA) content 94.0% by mass or more, saponification degree 98.5 ± 0.5 mol%, sodium acetate content 1.5% by mass or less, volatile content 5 0.0 mass% or less, viscosity (4 mass%, 20 ° C.) 5.6 ± 0.4 CPS], PVA-110 [PVA content 94.0 mass%, saponification degree 98.5 ± 0.5 mol%, acetic acid Sodium content 1.5% by mass, volatile matter 5.0% by mass, viscosity (4% by mass, 20 ° C.) 11.0 ± 0.8 CPS], PVA-117 [PVA content 94.0% by mass, saponification degree 98.5 ± 0.5 mol%, sodium acetate content 1.0 mass%, volatile content 5.0 mass%, viscosity (4 mass%, 20 ° C.) 28.0 ± 3.0 CPS],

PVA-117H [PVA content 93.5% by mass, saponification degree 99.6 ± 0.3 mol%, sodium acetate content 1.85% by mass, volatile matter 5.0% by mass, viscosity (4% by mass, 20% ° C) 29.0 ± 3.0 CPS], PVA-120 [PVA content 94.0 mass%, saponification degree 98.5 ± 0.5 mol%, sodium acetate content 1.0 mass%, volatile content 5. 0% by mass, viscosity (4% by mass, 20 ° C.) 39.5 ± 4.5 CPS], PVA-124 [PVA content 94.0% by mass, saponification degree 98.5 ± 0.5 mol%, sodium acetate contained 1.0 mass%, volatile matter 5.0 mass%, viscosity (4 mass%, 20 ° C.) 60.0 ± 6.0 CPS],

PVA-124H [PVA content 93.5% by mass, saponification degree 99.6 ± 0.3 mol%, sodium acetate content 1.85% by mass, volatile matter 5.0% by mass, viscosity (4% by mass, 20% ° C) 61.0 ± 6.0 CPS], PVA-CS [PVA content 94.0 mass%, saponification degree 97.5 ± 0.5 mol%, sodium acetate content 1.0 mass%, volatile content 5. 0 mass%, viscosity (4 mass%, 20 ° C.) 27.5 ± 3.0 CPS], PVA-CST [PVA content 94.0 mass%, saponification degree 96.0 ± 0.5 mol%, sodium acetate contained 1.0 mass%, volatile matter 5.0 mass%, viscosity (4 mass%, 20 ° C.) 27.0 ± 3.0 CPS], PVA-HC [PVA content 90.0 mass%, saponification degree 99. 85 mol% or more, sodium acetate content 2.5 mass%, volatile content 8.5 mass%, viscosity (4 mass%, 20 ℃) 25.0 ± 3.5CPS] (trade names, available from Kuraray Co.), etc.,

As a partially saponified product, PVA-203 [PVA content 94.0% by mass, saponification degree 88.0 ± 1.5 mol%, sodium acetate content 1.0% by mass, volatile matter 5.0% by mass, viscosity (4 mass%, 20 ° C.) 3.4 ± 0.2 CPS], PVA-204 [PVA content 94.0 mass%, saponification degree 88.0 ± 1.5 mol%, sodium acetate content 1.0 mass %, Volatile matter 5.0 mass%, viscosity (4 mass%, 20 ° C.) 3.9 ± 0.3 CPS], PVA-205 [PVA content 94.0 mass%, saponification degree 88.0 ± 1.5 Mol%, sodium acetate content 1.0% by mass, volatile matter 5.0% by mass, viscosity (4% by mass, 20 ° C.) 5.0 ± 0.4 CPS],

PVA-210 [PVA content 94.0% by mass, saponification degree 88.0 ± 1.0 mol%, sodium acetate content 1.0% by mass, volatile matter 5.0% by mass, viscosity (4% by mass, 20% ° C) 9.0 ± 1.0 CPS], PVA-217 [PVA content 94.0% by mass, saponification degree 88.0 ± 1.0 mol%, sodium acetate content 1.0% by mass, volatile content 5. 0% by mass, viscosity (4% by mass, 20 ° C.) 22.5 ± 2.0 CPS], PVA-220 [PVA content 94.0% by mass, saponification degree 88.0 ± 1.0 mol%, sodium acetate contained 1.0 mass%, volatile matter 5.0 mass%, viscosity (4 mass%, 20 ° C.) 30.0 ± 3.0 CPS],

PVA-224 [PVA content 94.0% by mass, saponification degree 88.0 ± 1.5 mol%, sodium acetate content 1.0% by mass, volatile matter 5.0% by mass, viscosity (4% by mass, 20% ° C) 44.0 ± 4.0 CPS], PVA-228 [PVA content 94.0% by mass, saponification degree 88.0 ± 1.5 mol%, sodium acetate content 1.0% by mass, volatile content 5. 0 mass%, viscosity (4 mass%, 20 ° C.) 65.0 ± 5.0 CPS], PVA-235 [PVA content 94.0 mass%, saponification degree 88.0 ± 1.5 mol%, sodium acetate contained 1.0 mass%, volatile matter 5.0 mass%, viscosity (4 mass%, 20 ° C.) 95.0 ± 15.0 CPS],

PVA-217EE [PVA content 94.0% by mass, saponification degree 88.0 ± 1.0 mol%, sodium acetate content 1.0% by mass, volatile matter 5.0% by mass, viscosity (4% by mass, 20% ° C) 23.0 ± 3.0 CPS], PVA-217E [PVA content 94.0 mass%, saponification degree 88.0 ± 1.0 mol%, sodium acetate content 1.0 mass%, volatile content 5. 0 mass%, viscosity (4 mass%, 20 ° C.) 23.0 ± 3.0 CPS], PVA-220E [PVA content 94.0 mass%, saponification degree 88.0 ± 1.0 mol%, sodium acetate contained 1.0 mass%, volatile matter 5.0 mass%, viscosity (4 mass%, 20 ° C.) 31.0 ± 4.0 CPS],

PVA-224E [PVA content 94.0% by mass, saponification degree 88.0 ± 1.0 mol%, sodium acetate content 1.0% by mass, volatile matter 5.0% by mass, viscosity (4% by mass, 20% ° C) 45.0 ± 5.0 CPS], PVA-403 [PVA content 94.0 mass%, saponification degree 80.0 ± 1.5 mol%, sodium acetate content 1.0 mass%, volatile content 5. 0 mass%, viscosity (4 mass%, 20 ° C.) 3.1 ± 0.3 CPS], PVA-405 [PVA content 94.0 mass%, saponification degree 81.5 ± 1.5 mol%, sodium acetate contained 1.0 mass%, volatile matter 5.0 mass%, viscosity (4 mass%, 20 ° C.) 4.8 ± 0.4 CPS],

PVA-420 [PVA content 94.0% by mass, saponification degree 79.5 ± 1.5 mol%, sodium acetate content 1.0% by mass, volatile matter 5.0% by mass], PVA-613 [PVA-containing Rate 94.0% by mass, degree of saponification 93.5 ± 1.0 mol%, sodium acetate content 1.0% by mass, volatile matter 5.0% by mass, viscosity (4% by mass, 20 ° C.) 16.5 ± 2.0 CPS], L-8 [PVA content 96.0 mass%, saponification degree 71.0 ± 1.5 mol%, sodium acetate content 1.0 mass% (ash content), volatile content 3.0 mass% Viscosity (4% by mass, 20 ° C.) 5.4 ± 0.4 CPS] (all are trade names manufactured by Kuraray Co., Ltd.).

  In addition, said measured value was calculated | required according to JISK-6726-1977.

  As for the modified polyvinyl alcohol, those described in Koichi Nagano et al., “Poval” (published by Kobunshi Shuppankai) are used. There is modification by cation, anion, -SH compound, alkylthio compound, silanol.

  As such modified polyvinyl alcohol (modified PVA), C-118, C-318, C-318-2A, C-506 (all are trade names manufactured by Kuraray Co., Ltd.), HL polymer as C polymer. HL-12E, HL-1203 (all are trade names manufactured by Kuraray Co., Ltd.), HM polymer is HM-03, HM-N-03 (all are trade names manufactured by Kuraray Co., Ltd.), KL-118, KL-318, KL-506, KM-118T, KM-618 (all are trade names manufactured by Kuraray Co., Ltd.) as the K polymer, and M-115 (manufactured by Kuraray Co., Ltd.) as the M polymer. (Trade name), MP-102, MP-202, MP-203 (all are trade names manufactured by Kuraray Co., Ltd.) as MP polymers, MPK-1, MPK-2, MPK-3, PK-4, MPK-5, MPK-6 (all are trade names manufactured by Kuraray Co., Ltd.), R polymer as R-1130, R-2105, R-2130 (all are manufactured by Kuraray Co., Ltd.) And V-2250 (trade name, manufactured by Kuraray Co., Ltd.).

  Polyvinyl alcohol can be adjusted in viscosity or stabilized by a small amount of solvent or inorganic salt added to the aqueous solution. For details, refer to the above document, Koichi Nagano et al., “Poval”, Polymer Issued by the publisher, pages 144 to 154 can be used. As a typical example, it is possible to improve the coating surface quality by containing boric acid, which is preferable. The amount of boric acid added is preferably 0.01 to 40% by mass relative to polyvinyl alcohol.

  Suitable binders are transparent or translucent, generally colorless, and are natural resins, polymers and copolymers, synthetic resins, polymers and copolymers, and other film-forming media such as rubbers, polyvinyl alcohols, hydroxyethyl celluloses, cellulose Acetates, cellulose acetate butyrate, polyvinylpyrrolidone, starch, polyacrylic acid, polymethylmethacrylic acid, polyvinyl chloride, polymethacrylic acid, styrene-maleic anhydride copolymers, styrene-acrylonitrile copolymers , Styrene-butadiene copolymers, polyvinyl acetals (eg, polyvinyl formal and polyvinyl butyral), polyesters, polyurethanes, phenoxy resins, polyvinylidene chlorides, polyepoxides , Polycarbonates, polyvinyl acetates, polyolefins, cellulose esters, and polyamides such water-soluble.

In the present invention, the water-soluble polymer is preferably polyvinyl alcohol or gelatin, and most preferably gelatin.
The addition amount of the water-soluble polymer in the receiving layer is preferably 1 to 25% by mass, and more preferably 1 to 10% by mass with respect to the entire receiving layer.

<Crosslinking agent>
It is preferable that part or all of the water-soluble polymer contained in the receiving layer is crosslinked with a crosslinking agent.
As the crosslinking agent, a plurality of groups capable of reacting with an amino group, a carboxyl group, a hydroxyl group, or the like may be contained in the molecule. The crosslinking agent is appropriately selected according to the type of the water-soluble polymer. It is not limited. Each method described in THJames, “THE THEORY OF THE PHOTOGRAPHIC PROCESS FOURTH EDITION” (Macmillan Publishing Co., Inc., published in 1977), pages 77-87, and US Pat. No. 4,678,739 The crosslinking agents described in column 41, JP-A-59-116655, JP-A-62-245261, JP-A-61-18942 and the like are suitable for use. Both an inorganic compound crosslinking agent (for example, chromium alum, boric acid and salts thereof) and an organic compound crosslinking agent are preferred. Moreover, you may use the crosslinking agent which consists of mixed aqueous solution containing the chelating agent and zirconium compound which are 1-7 of pH of Unexamined-Japanese-Patent No. 2003-231775.

  Specific examples of the crosslinking agent include epoxy compounds (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, compounds described in JP-A-6-329877 and JP-A-7-309954, or Dick Fine EM-60 (trade name, Dainippon Ink & Chemicals, Inc.) Aldehyde compounds (formaldehyde, glyoxal, glutaraldehyde, etc.); active halogen compounds (2,4-dichloro-4-hydroxy-1,3,5-s-triazine, US Pat. No. 3, 325,287 A compound according to Saisho etc.);

Active vinyl compounds (1,3,5-trisacryloyl-hexahydro-s-triazine, bisvinylsulfonylmethyl ether, N, N′-ethylene-bis (vinylsulfonylacetamide) ethane, Japanese Patent Publication No. 53-41220, Compounds described in JP-A-53-57257, JP-A-59-162546, JP-A-60-80846, etc.); mucohalic acid compounds (such as mucochloric acid); N-carbamoylpyridinium salt compounds ((1-morpholinocarbonyl-3) -Pyridinio) methanesulfonate, etc.); haloamidinium salt compounds (1- (1-chloro-1-pyridinomethylene) pyrrolidinium, 2-naphthalenesulfonate, etc.); N-methylol compounds (dimethylolurea, methyloldimethylhydantoin, etc.) );

Carbodiimide compounds (polycarbodiimides derived from isophorone diisocyanate described in JP-A-59-187029 and JP-B-5-27450, carbodiimide compounds derived from tetramethylxylylene diisocyanate described in JP-A-7-330849, Other branched carbodiimide compounds described in JP-A-10-30024, and carbodiimide compounds derived from dicyclohexylmethane diisocyanate described in JP-A-2000-7642, or carbodilite V-02, V-02-L2, V-04, V-06 , E-01, E-02 (both trade names, Nisshinbo Co., Ltd.), etc .; Oxazoline compounds (oxazoline compounds described in JP-A No. 2001-215653, or Epocros K-1010E, K-1020E, K- 030E, K-2010E, K-2020E, K-2030E, WS-500, WS-700 (trade names, manufactured by Nippon Shokubai Co., Ltd.), and the like);

Isocyanate compounds (JP-A-7-304841, JP-A-8-277315, JP-A-10-45866, JP-A-9-71720, JP-A-9-328654, JP-A-9-104814 , JP-A-2000-194045, JP-A-2000-194237, and JP-A-2003-64149, dispersible isocyanate compounds, or Duranate WB40-100, WB40-80D, WT20-100, WT30-100 ( All are trade names, Asahi Kasei Co., Ltd.), CR-60N (trade name, Dainippon Ink and Chemicals), etc.); polymer hardeners (compounds described in JP-A-62-2234157, etc.); boric acid And salts thereof; borax; aluminum alum and the like.

  The cross-linking agent used in the present invention may be added in a state of being premixed in a water-soluble polymer solution, may be added at the end of the preparation process of the coating solution, or may be added immediately before coating. .

Although the water-soluble polymer in the receiving layer varies depending on the type of the crosslinking agent, it is preferably 0.1 to 20% by mass crosslinked with respect to the water-soluble polymer, and 1 to 10% by mass crosslinked. Is more preferable.
The amount of the crosslinking agent used in the present invention varies depending on the type of the water-soluble binder and the crosslinking agent, but is generally 0.1 to 50 parts by mass with respect to 100 parts by mass of the water-soluble polymer in the constituent layer. It is preferably 0.5 to 20 parts by mass, and more preferably 1 to 10 parts by mass.

<Ultraviolet absorber>
In the present invention, an ultraviolet absorber may be added to the receiving layer in order to improve light resistance. At this time, the UV absorber can be fixed to the receiving layer by increasing the molecular weight, and can be prevented from being diffused into the ink sheet or sublimation / transpiration due to heating.
As the ultraviolet absorber, compounds having various ultraviolet absorber skeletons widely known in the field of information recording can be used. Specific examples include 2-hydroxybenzotriazole type ultraviolet absorbers, 2-hydroxybenzotriazine type ultraviolet absorbers, and compounds having a 2-hydroxybenzophenone type ultraviolet absorber skeleton. A compound having a benzotriazole type or triazine skeleton is preferable from the viewpoint of ultraviolet absorption ability (absorption coefficient) / stability, and a compound having a benzotriazole type or benzophenone type skeleton is preferable from the viewpoint of increasing the molecular weight or forming a latex. Specifically, an ultraviolet absorber described in JP 2004-361936 A can be used.

  The ultraviolet absorber preferably has absorption in the ultraviolet region and does not have an absorption edge in the visible region. Specifically, when added to the receiving layer to form a thermal transfer image-receiving sheet, the reflection density at 370 nm is preferably Abs 0.5 or more, and the reflection density at 380 nm is more preferably Abs 0.5 or more. . The reflection density at 400 nm is preferably Abs 0.1 or less. A high reflection density in the range exceeding 400 nm is not preferable because the image is yellowed.

  In the present invention, the ultraviolet absorber has a high molecular weight and preferably has a mass average molecular weight of 10,000 or more, more preferably a mass average molecular weight of 100,000 or more. As a means for increasing the molecular weight, it is preferable to graft an ultraviolet absorber onto the polymer. The polymer that becomes the main chain preferably has a polymer skeleton that is inferior in dyeability to the dye used in combination. Moreover, it is preferable to have sufficient film strength when the film is formed. The graft ratio of the ultraviolet absorber to the polymer main chain is preferably 5 to 20% by mass, and more preferably 8 to 15% by mass.

  When the polymer to which the ultraviolet absorber is grafted is made into a latex, it is possible to form a receiving layer in which the ultraviolet absorber is uniformly dispersed by mixing with the latex of the above-mentioned dyeable receiving polymer and applying it.

  The added amount of the polymer grafted with the ultraviolet absorber or the latex thereof is preferably 5 to 50 parts by mass, more preferably 10 to 30 parts by mass with respect to the dyeable accepting polymer latex forming the receptor layer.

<Emulsified dispersion>
In the present invention, it is preferable to contain an emulsified dispersion (emulsion) in the receiving layer. Here, “emulsification” is in accordance with a commonly used definition. For example, according to the Dictionary of Chemistry (Kyoritsu Shuppan Co., Ltd.), “emulsification” is defined as “a phenomenon in which another liquid that does not dissolve in one liquid is dispersed as fine particles to produce an emulsion”. The “emulsified dispersion” means “liquid droplets dispersed in another liquid that does not dissolve them”. In the present invention, a preferable “emulsified dispersion” is an “oil droplet dispersion dispersed in water”. The content of an emulsified dispersion in the image receiving sheet of the present invention is preferably contained 0.03g ^{/ m 2} ~25.0g ^/ m 2 during the image-receiving ^{sheet, 1.0g / m 2 ~20.0g / m} 2 It is preferably included.

In the present invention, it is preferable that a high boiling point solvent is contained in the oil-soluble component of the emulsified dispersion. Preferred high boiling point solvents include phthalates (dibutyl phthalate, dioctyl phthalate, di-2-ethylhexyl phthalate, etc.), phosphoric acid or phosphonic esters (triphenyl phosphate, tricresyl phosphate, triphosphate phosphate). 2-ethylhexyl, etc.), fatty acid esters (di-2-ethylhexyl succinate, tributyl citrate, etc.), benzoates (2-ethylhexyl benzoate, dodecyl benzoate, etc.), amides (N, N-diethyl, etc.) Dodecanamide, N, N-dimethyloleamide, etc.), alcohol or phenols (isostearyl alcohol, 2,4-di-tert-amylphenol, etc.), anilines (N, N-dibutyl-2-butoxy-5-) tert-octylaniline), chlorinated paraffins, hydrocarbons ( Decylbenzene, diisopropylnaphthalene, etc.), carboxylic acids (2- (2,4-di-tert-amylphenoxy) butyric acid, etc. More preferably, the high-boiling solvent is phosphoric acid or phosphonic acid esters (triphosphate phosphate). Phenyl, tricresyl phosphate, tri-2-ethylhexyl phosphate, etc. In addition, as an auxiliary solvent, an organic solvent having a boiling point of 30 ° C. or higher and 160 ° C. or lower (ethyl acetate, butyl acetate, methyl ethyl ketone, cyclohexanone, methyl cellosolve acetate, dimethyl) The high boiling point solvent is preferably contained in the emulsion dispersion in an amount of 3.0 to 25% by mass, more preferably 5.0 to 20% by mass.
Further, the emulsified dispersion preferably contains an image fastening agent and an ultraviolet absorber. These compounds are represented by the general formulas (B), (Ph), (E-1) to (E-3), (TS-I) to (TS-VII), ( A compound represented by any of (TS-VIIIA) and (UA) to (UE) is preferable. Further, it may contain a water-insoluble and organic solvent-soluble homopolymer or copolymer (preferably the compounds described in paragraph Nos. 0208 to 0234 of JP-A No. 2004-361936).

<Release agent>
In addition, a release agent may be added to the receiving layer in order to prevent thermal fusion with the thermal transfer sheet during image formation. As the release agent, silicone oil and phosphoric ester plasticizer fluorine compound can be used, and silicone oil is particularly preferably used. As the silicone oil, modified silicone oils such as epoxy modification, alkyl modification, amino modification, carboxyl modification, alcohol modification, fluorine modification, alkylaralkyl polyether modification, epoxy / polyether modification, and polyether modification are preferably used. The reaction product of vinyl modified silicone oil and hydrogen modified silicone oil is good. In the present invention, microcrystalline wax is used as a release agent in the receiving layer. The addition amount of the release agent is preferably 0.2 to 30 parts by mass with respect to the receiving polymer.

The coating amount of the receiving layer is preferably 0.5 to 10 g / m ² (in terms of solid content, hereinafter the coating amount in the present invention is a numerical value in terms of solid content unless otherwise specified). The thickness of the receiving layer is preferably 1 to 20 μm.

(Insulation layer)
The heat insulating layer serves to protect the support from heat during heat transfer using a thermal head. Moreover, since it has high cushioning properties, a thermal transfer image-receiving sheet with high printing sensitivity can be obtained even when paper is used as the substrate. The heat insulating layer may be one layer or two or more layers. The heat insulating layer is provided on the support side from the receptor layer.

In the image receiving sheet of the present invention, the heat insulating layer contains a hollow polymer.
The hollow polymer in the present invention is a polymer particle having independent pores inside the particle. For example, 1) Water is contained inside a partition formed by polystyrene, acrylic resin, styrene-acrylic resin, etc., and after coating and drying Non-foamed hollow particles in which the water inside the particles evaporates outside the particles and the inside of the particles becomes hollow. 2) Low boiling point liquids such as butane and pentane, polyvinylidene chloride, polyacrylonitrile, polyacrylic acid, polyacrylic A foamed microballoon covered with a resin comprising any of acid esters, a mixture or a polymer thereof, and after coating, the low-boiling liquid inside the particles expands by heating, and the inside becomes hollow 3) above (2) can be heated and foamed in advance to form a hollow polymer.
Among these, in the present invention, a non-foamed hollow polymer latex formed of styrene-acrylic resin or the like is used.

These hollow polymers preferably have a hollow ratio of about 20 to 70%, and can be used by mixing two or more kinds as necessary. Specific examples of 1) include Low and Haas Ropaque 1055, Dainippon Ink Boncoat PP-1000, JSR SX866 (B), Nippon Zeon Nipol MH5055 (all trade names), and the like. . Specific examples of 2) include F-30 and F-50 (both trade names) manufactured by Matsumoto Yushi Seiyaku Co., Ltd. Specific examples of 3) include F-30E manufactured by Matsumoto Yushi Seiyaku Co., Ltd., EXPANSEL 461DE, 551DE, and 551DE20 (all trade names) manufactured by Nippon Ferrite Co., Ltd. Hollow polymer of the invention used in the heat insulation layer is a latex.

  The heat insulating layer containing the hollow polymer preferably contains a water-dispersed resin or a water-soluble resin as a binder resin as a binder resin. Examples of the binder resin used in the present invention include acrylic resins, styrene-acrylic copolymers, polystyrene resins, polyvinyl alcohol resins, vinyl acetate resins, ethylene-vinyl acetate copolymers, vinyl chloride vinyl acetate copolymers, and styrene. Known resins such as butadiene copolymers, polyvinylidene chloride resins, cellulose derivatives, casein, starch, and gelatin can be used. These resins can be used alone or in combination.

The solid content of the hollow polymer in the heat insulating layer is preferably between 5 and 2000 parts by mass when the solids content of the binder resin is 100 parts by mass. Moreover, 1-70 mass% is preferable, and, as for the mass ratio which occupies with respect to the coating liquid of the solid content of a hollow polymer, 10-40 mass% is more preferable. If the ratio of the hollow polymer is too small, sufficient heat insulation cannot be obtained, and if the ratio of the hollow polymer is too large, the binding force between the hollow polymers decreases, causing problems such as powder falling off during processing or film peeling. Arise.
The particle size of the hollow polymer is preferably from 0.1 to 20 μm, more preferably from 0.1 to 2 μm, particularly preferably from 0.1 to 1 μm. In the present invention, the particle size of the hollow polymer is 0.1 to 2 μm. Further, the glass transition temperature (Tg) of the hollow polymer is preferably 70 ° C. or higher, and more preferably 100 ° C. or higher.

In the heat-receiving layer, the image-receiving sheet of the present invention does not contain an aqueous dispersion of a resin that is not resistant to organic solvents, in addition to the hollow polymer. It is not preferable to include a resin (dye dyeing resin) that is not resistant to an organic solvent in the heat insulating layer because blurring of an image after image transfer increases. This is because the dye-stainable resin and the hollow polymer exist in the heat insulating layer, so that the dye dyed on the receiving layer after the transfer moves over time through the adjacent heat-insulating layer. it is conceivable that.
Here, “not resistant to organic solvent” means that the solubility in an organic solvent is 1% by mass or less, preferably 0.5% by mass or less. For example, the polymer latex is included in “resin not resistant to organic solvent”.

Moreover, it is preferable that a heat insulation layer contains the said water-soluble polymer. The compounds that can be preferably used are the same as described above.
The amount of the water-soluble polymer added to the heat insulating layer is preferably 1 to 75% by mass and more preferably 1 to 50% by mass with respect to the entire heat insulating layer.

The heat insulating layer preferably contains gelatin. The amount of the heat insulating layer in the gelatin coating solution is preferably 0.5 to 14% by mass, particularly preferably 1 to 6% by mass. The coating amount of the hollow polymer in the heat insulation layer is preferably ^{1~100g / m 2, 5~20g / m} 2 is more preferable.

Moreover, it is preferable that the water-soluble polymer contained in the heat insulation layer is crosslinked by a crosslinking agent. The preferred range of the crosslinking agent that can be preferably used and the amount of use thereof is the same as described above.
Although the water-soluble polymer in the heat insulating layer varies depending on the type of the crosslinking agent, it is preferably 0.1 to 20% by mass crosslinked with respect to the water-soluble polymer, and 1 to 10% by mass crosslinked. Is more preferable.

  The thickness of the heat insulating layer containing the hollow polymer is preferably 5 to 50 μm, and more preferably 5 to 40 μm.

(Underlayer)
In the present invention, an underlayer is formed between the support and the heat insulating layer in contact with the heat insulating layer.
Further, between the support and the heat insulation layer, a white background controlling layer In example embodiment, a charge controlling layer, an adhesive layer may be a primer layer is formed, for these layers, for example, Patent No. 3585599, JP It can be set as the structure similar to what was described in 2925244 specification.

(Support)
In the present invention, used as supporting lifting bodies of both surfaces or at least receiving layer is provided a resin layer on the surface on the side provided structure of the base paper. As the resin used for the resin layer, commonly known resins such as polyethylene and polypropylene are used. The present invention is characterized in that no adhesive is used when a resin layer is provided on a base paper. Melt extrusion is preferred for providing the resin layer on the paper support.
However, in the present invention, it is essential that the support is provided with polyethylene resin on both sides of the base paper.

The raw material of the base paper is not particularly limited, and examples thereof include natural pulp selected from coniferous and hardwood, synthetic pulp made of plastic materials such as polyethylene and polypropylene, or a mixture of synthetic pulp and natural pulp.
The pulp that can be used as the raw material of the base paper is hardwood bleached kraft pulp (LBKP) from the viewpoint of improving the surface smoothness, rigidity and dimensional stability (curlability) of the base paper to a sufficient balance at the same time. It is preferable to use softwood bleached kraft pulp (NBKP) or the like. Hardwood sulfite pulp (LBSP) or the like can also be used. It is appropriate to use mainly hardwood pulp having a short fiber length as the main pulp fiber. Beaters and refiners can be used to beat the pulp. Various additives such as a filler, a dry paper strength enhancer, a sizing agent, a wet paper strength enhancer, a fixing agent, a pH adjuster, and other chemicals can be added to the pulp slurry obtained after beating the pulp as necessary. Examples of these are described in paragraph numbers 0021 to 0025 of JP-A-2004-271790.
The density of the base paper is preferably 0.9 g / m ² or more, more preferably 0.95 g / m ² or more and 1.2 g / m ² or less. The thickness of the base paper can be appropriately selected according to the purpose, but is usually preferably 50 to 300 μm, more preferably 100 to 250 μm.
Tsuboryo of the base paper is not particularly limited and may be selected according to the purpose, for example, preferably ^{50~250g / m 2, 100~200g / m} 2 is particularly preferred.

Po Riechire down resins on base paper as far as possible the extrusion coating can be selected depending on the intended purpose without any restriction on its molecular weight. In particular, a polyolefin having a molecular weight in the range of 20,000 to 200,000 is preferred. In the present invention, the resins and additives described in paragraph Nos. 0031 to 0048 of JP-A No. 2004-271790 can be used depending on the purpose.
It is preferable that a curl adjusting layer, a writing layer, and a charge adjusting layer are formed on the back side of the support. Each layer on the back side of the support can be applied by a general method such as roll coating, bar coating, gravure coating, or gravure reverse coating.
As the paper support, in addition to the base paper, coated paper and laminated paper can be used.
-Coated paper-
The coated paper is a paper obtained by coating various sheets of resin, rubber latex, or polymer material on one side or both sides of a sheet such as a base paper, and the coating amount varies depending on the application. Examples of such coated paper include art paper, cast coated paper, Yankee paper, and the like.

  As the resin applied to the surface of the base paper or the like, it is appropriate to use a thermoplastic resin. Examples of such a thermoplastic resin include the following thermoplastic resins (a) to (h).

(A) Polyolefin resins such as polyethylene resins and polypropylene resins, copolymer resins of olefins such as ethylene and propylene and other vinyl monomers, acrylic resins, and the like.
(B) A thermoplastic resin having an ester bond. For example, a dicarboxylic acid component (these dicarboxylic acid components may be substituted with a sulfonic acid group, a carboxyl group, etc.) and an alcohol component (these alcohol components may be substituted with a hydroxyl group, etc.) Polyester resin, polymethyl methacrylate, polybutyl methacrylate, polymethyl acrylate, polybutyl acrylate and other polyacrylic acid ester resins or polymethacrylic acid ester resins, polycarbonate resins, polyvinyl acetate resins, styrene acrylate resins, styrene -Methacrylic acid ester copolymer resin, vinyl toluene acrylate resin, etc. are mentioned.
Specific examples include those described in JP-A Nos. 59-101395, 63-7971, 63-7972, 63-7773, and 60-294862. it can.
Commercially available products include Byron 290, Byron 200, Byron 280, Byron 300, Byron 103, Byron GK-140, Byron GK-130 manufactured by Toyobo Co., Ltd., Tufton NE-382, Tufton manufactured by Kao Corporation U-5, ATR-2009, ATR-2010; Elitel UE3500, UE3210, XA-8153, KZA-7049, KZA-1449 manufactured by Unitika Ltd. Polyester TP-220, R manufactured by Nippon Synthetic Chemical Co., Ltd. -188; various types of thermoplastic resins of the Hiros series manufactured by Seiko Chemical Industry Co., Ltd. (all trade names).

(C) Polyurethane resin etc. are mentioned.
(D) Polyamide resin, urea resin, etc. are mentioned.
(E) Polysulfone resin and the like.
(F) Polyvinyl chloride resin, polyvinylidene chloride resin, vinyl chloride-vinyl acetate copolymer resin, vinyl chloride-vinyl propionate copolymer resin, and the like.
(G) Cellulose resins such as polyol resins, ethyl cellulose resins, and cellulose acetate resins, such as polyvinyl butyral.
(H) Polycaprolactone resin, styrene-maleic anhydride resin, polyacrylonitrile resin, polyether resin, epoxy resin, phenol resin and the like.
In addition, the said thermoplastic resin may be used individually by 1 type, and may use 2 or more types together.

  Further, the thermoplastic resin may contain pigments or dyes such as brighteners, conductive agents, fillers, titanium oxide, ultramarine blue, and carbon black as required.

-Laminated paper-
The laminated paper is a paper obtained by laminating various resins, rubber or polymer sheets or films on a sheet such as a base paper. Examples of the laminate material include polyolefin, polyvinyl chloride, polyethylene terephthalate, polystyrene, polymethacrylate, polycarbonate, polyimide, triacetyl cellulose, and the like. These resins may be used alone or in combination of two or more. However, a polyethylene resin is used in the present invention.

  In general, the polyolefin is often formed using low density polyethylene, but in order to improve the heat resistance of the support, polypropylene, a blend of polypropylene and polyethylene, high density polyethylene, high density polyethylene and low density polyethylene, It is preferable to use a blend of In particular, it is most preferable to use a blend of high-density polyethylene and low-density polyethylene from the viewpoint of cost, suitability for lamination, and the like.

The blend of the high density polyethylene and the low density polyethylene is used, for example, in a blend ratio (mass ratio) of 1/9 to 9/1. The blend ratio is preferably 2/8 to 8/2, and more preferably 3/7 to 7/3. When forming a thermoplastic resin layer on both surfaces of the support, the back surface of the support is preferably formed using, for example, high-density polyethylene or a blend of high-density polyethylene and low-density polyethylene. The molecular weight of polyethylene is not particularly limited, but the melt index is 1.0 to 40 g / 10 min for both high-density polyethylene and low-density polyethylene, and has an extrudability. Particularly preferred are polyolefins having a molecular weight in the range of 20,000 to 200,000. In the present invention, the resins and additives described in paragraph Nos. 0031 to 0048 of JP-A No. 2004-271790 can be used depending on the purpose.
In addition, you may perform the process which gives white reflectivity to these sheets or films. Examples of such a treatment method include a method of blending a pigment such as titanium oxide in these sheets or films.

  The thickness of the support is preferably 25 μm to 300 μm, more preferably 50 μm to 260 μm, and still more preferably 75 μm to 220 μm. Various stiffnesses can be used according to the purpose, and the support for a photographic image receiving sheet for electrophotography is close to a support for color silver halide photography. Those are preferred.

It is preferable that the Beck smoothness on the surface of the support on the side of the support used in the present invention is 10,000 seconds or more and the center line average roughness (Ra) is 0.5 μm or less. More preferably, the Beck smoothness of the surface of the support on the side of the support used in the present invention is 15000 seconds or more and the center line average roughness (Ra) is 0.4 μm or less. The Beck smoothness on the side of the support on which the back layer is provided (that is, the side opposite to the side having the receiving layer) is preferably 1300 seconds or less, and the center line average roughness (Ra) is 0.75 μm or more. 10 μm or less and the local peak sum average distance (S) are preferably 30 μm or more and 75 μm or less.
Here, the Beck smoothness can be measured using a Beck smoothness tester based on JIS P8119. The centerline average roughness (Ra) and the local peak average interval (S) are JIS
This is based on the definition of surface roughness in B0601, and can be measured using, for example, a surface shape measuring machine.

(Curl adjustment layer)
If the support is exposed as it is, the heat-sensitive transfer image-receiving sheet may be curled due to the humidity and temperature in the environment. Therefore, it is preferable to form a curl adjusting layer on the back side of the support. The curl adjusting layer not only prevents the image receiving sheet from curling but also serves as a waterproof. For the curl adjusting layer, polyethylene laminate, polypropylene laminate, or the like is used. Specifically, it can be formed in the same manner as described in, for example, JP-A-61-110135 and JP-A-6-202295.

(Writing layer / Charge adjustment layer)
An inorganic oxide colloid, an ionic polymer, or the like can be used for the writing layer and the charge adjusting layer. As the antistatic agent, for example, a cationic antistatic agent such as a quaternary ammonium salt or a polyamine derivative, an anionic antistatic agent such as an alkyl phosphate, or a nonionic antistatic agent such as a fatty acid ester can be used. . Specifically, it can be formed in the same manner as that described in, for example, Japanese Patent No. 3585585.

The method for producing the thermal transfer image receiving sheet of the present invention will be described below.
The heat-sensitive transfer image-receiving sheet of the present invention can be produced by applying each layer by a general method such as roll coating, bar coating, gravure coating, and gravure reverse coating, and drying them.
The heat-sensitive transfer image-receiving sheet of the present invention can also be formed by simultaneously applying a receiving layer and a heat insulating layer on a support.
When producing a multi-layer image receiving sheet comprising a plurality of layers having different functions (such as a bubble layer, a heat insulating layer, an intermediate layer, and a receiving layer) on a support, JP-A Nos. 2004-106283 and 2004-181888 are disclosed. In addition, it is known that each layer is sequentially coated as disclosed in each publication such as JP-A 2004-345267, or the layers are previously applied on a support and bonded together. On the other hand, it is known in the photographic industry that productivity is greatly improved, for example, by applying a plurality of layers simultaneously. For example, U.S. Pat. Nos. 2,761,791, 2,681,234, 3,508,947, 4,457,256, 3,993,019, JP 63-54975, JP-A-61-278848, 55-86557, 52-31727, 55-142565, 50-43140, 63-80872, 54-54020, Special Publications and specifications of Kaihei 5-104061, 5-127305, JP-B 49-7050, and Edgar B. Gutoff et al., "Coating and Drying Defects: Troubleshooting Operating Problems", John Wiley & Sons, 1995, 101. Methods known as slide coating (slide coating method) and curtain coating (curtain coating method) described in pp. 103 and the like are known.
In the present invention, the simultaneous multi-layer coating is used for manufacturing a multi-layer image-receiving sheet, whereby productivity can be greatly improved and image defects can be greatly reduced.

In the present invention, the plurality of layers are composed mainly of a resin. The coating solution for forming each layer is preferably water-dispersed latex. The solid content mass of the latex resin in the coating solution of each layer is preferably in the range of 5 to 80%, particularly preferably in the range of 20 to 60%. The average particle size of the resin contained in the water-dispersed latex is 5 μm or less and particularly preferably 1 μm or less. The water-dispersed latex may contain a known additive such as a surfactant, a dispersant, and a binder resin as necessary.
In the present invention, it is preferable to form a laminate of a plurality of layers on a support by the method described in US Pat. No. 2,761,791 and then solidify immediately. As an example, in the case of a multilayer structure solidified by a resin, it is preferable to quickly raise the temperature after forming a plurality of layers on the support. When a binder that gels at a low temperature such as gelatin is included, it may be preferable to quickly lower the temperature after forming a plurality of layers on the support.
The coating amount of a coating solution per one layer constituting the multilayer in the present invention in the range of 1g / m ² ~500g / m ² is preferred. The number of layers in the multilayer configuration can be arbitrarily selected as 2 or more. The receiving layer is preferably provided as the layer furthest away from the support.

  The thermal transfer image-receiving sheet of the present invention preferably has an appropriate elastic modulus. For example, the elastic modulus measured by the method described in JP-A No. 2002-200851 is preferably 10% or more and 30% or less.

The thermal transfer image receiving sheet of the present invention is preferably smooth. The Beck smoothness is preferably 700 seconds or more, particularly preferably 2000 seconds or more.
The thermal transfer image-receiving sheet of the present invention preferably has an appropriate rigidity. For example, the rigidity specified in TAPPI T54384 is preferably 500 to 1500 standard Gurley units.
Further, the thermal transfer receiving sheet of the present invention needs to have an appropriate papermaking friction coefficient with the rubber roller for conveyance, and it is preferable that the static friction coefficient with at least one side of the rubber roller is 0.5 or more.

In the image forming method using the heat-sensitive transfer image-receiving sheet of the present invention, the heat-sensitive transfer sheet (ink sheet) used in combination with the heat-sensitive transfer image-receiving sheet of the present invention described above is diffused on the support when the heat-transfer image is formed. A pigment layer containing a transfer dye is provided, and any ink sheet can be used. As the means for applying thermal energy at the time of thermal transfer, any conventionally known means for applying can be used. For example, recording is performed by a recording device such as a thermal printer (for example, product name, video printer VY-100, manufactured by Hitachi, Ltd.). By controlling the time, the intended purpose can be sufficiently achieved by applying thermal energy of about 5 to 100 mJ / mm ² .
The heat-sensitive transfer image-receiving sheet of the present invention can be applied to various uses such as a sheet- or roll-shaped heat-sensitive transfer image-receiving sheet, cards, and transmission-type manuscript preparation sheets capable of thermal transfer recording by appropriately selecting a support. You can also

The present invention can be used in printers, copiers and the like using a thermal transfer recording system.
The heat-sensitive transfer image-receiving sheet of the present invention can be supplied in a roll form using a paper core or a plastic core, or can be supplied in a roll form without a core. It can also be supplied in sheet form.

EXAMPLES Hereinafter, although this invention is demonstrated in detail based on an Example, this invention is not limited to these. In Examples, “part” or “%” is based on mass unless otherwise specified.
Reference example (preparation of ink sheet)
A polyester film having a thickness of 6.0 μm (Lumirror, trade name, manufactured by Toray Industries, Inc.) was used as a base film. A heat-resistant slip layer (thickness 1 μm) was formed on the back side of the film, and yellow, magenta and cyan compositions having the following compositions were applied to the surface side in a single color (coating amount 1 g / m ² during dry film formation).
Yellow composition Dye (Macrolex Yellow 6G, trade name, manufactured by Bayer) 5.5 parts by weight Polyvinyl butyral resin 4.5 parts by weight (ESREC BX-1, trade name, manufactured by Sekisui Chemical Co., Ltd.)
Methyl ethyl ketone / toluene (mass ratio 1/1) 90 parts by mass Magenta composition Magenta dye (Disperse Red 60) 5.5 parts by mass Polyvinyl butyral resin 4.5 parts by mass (ESREC BX-1, trade name, Sekisui Chemical Co., Ltd.) Made by Co., Ltd.)
Methyl ethyl ketone / toluene (mass ratio 1/1) 90 parts by mass Cyan composition Cyan dye (Solvent Blue 63) 5.5 parts by mass Polyvinyl butyral resin 4.5 parts by mass (ESREC BX-1, trade name, Sekisui Chemical Co., Ltd.) ) Made)
90 parts by mass of methyl ethyl ketone / toluene (mass ratio 1/1)

Example 1
<Production of image receiving sheet>
(Production of support)
Preparation of Support 1 50 parts by mass of LBKP made of acacia and 50 parts by mass of LBKP made of aspen were each beaten to 300 ml of Canadian freeness by a disc refiner to prepare a pulp slurry.
Next, to the pulp slurry obtained above, cation modified starch (CAT0304L manufactured by NSC Japan) 1.3%, anionic polyacrylamide (DA4104 manufactured by Seiko PMC) 0.15%, alkyl ketene dimer (Arakawa Chemical) per pulp. Size pine K) 29%, 0.29% epoxidized behenamide, 0.32% polyamide polyamine epichlorohydrin (Arakawa Chemical Co., Ltd .: Arafix 100) were added, and then 0.12% of an antifoaming agent was added.

In the process of making the pulp slurry prepared as described above with a long paper machine and pressing the felt surface of the web against the drum dryer cylinder through the dryer canvas, the tensile force of the dryer canvas is 1.6 kg / After drying by setting to cm, 1 g / m ² of polyvinyl alcohol (manufactured by Kuraray Co., Ltd .: KL-118) was applied to both sides of the base paper with a size press and dried to perform calendar treatment. The base paper was made with a basis weight of 157 g / m ² to obtain a base paper (base paper) having a thickness of 160 μm.

This base paper was run at a speed of 150 m / min, and after corona discharge treatment on the back side, 10 parts of low density polyethylene (density 0.924 g / m ³ MI = 3 g / 10 min), high density polyethylene (density 0.966 g / m ³ MI = 11 g / 10 min) 90 μm layer, low density polyethylene (density 0.922 g / m ³ MI = 5 g / 10 min) 50 parts, high density polyethylene (density 0.970 g / m ³ MI = 20 g / 10 min) 50 parts The outermost layer of 15 μm is melt-extruded using a coat hanger type two-layer co-extrusion die, and immediately after that, using a chill roll having a mat surface whose centerline average roughness (Ra) and cooling temperature are appropriately adjusted. Molded to provide a matte resin layer.
Furthermore, after corona discharge treatment was applied to the surface of the base paper, a 15 μm layer made of low-density polyethylene (density 0.920 g / m ³ MI = 5 g / 10 min) was used using a two-layer coat hanger type two-layer co-extrusion die. Then, it was melt-extruded, and immediately after that, a glossy resin layer was provided by molding using a cooling roll having a fine mat surface whose average roughness and cooling temperature were appropriately adjusted.

Production of Support 2 Instead of providing a polyethylene layer on the base paper surface of the support, a polyethylene film having a thickness of 30 μm was uniformly attached by the following steps. That is, after corona discharge treatment on the surface of the base paper, a polyfunctional polyol (Takelac A-969V, Takeda Pharmaceutical Co., Ltd.), isocyanate (Takenate A-5, Takeda Pharmaceutical Co., Ltd.), and ethyl acetate are in a ratio of 3 to 1: 6. After applying the adhesive mixed in (mass ratio) at 3 g / m ² , a commercially available polyester film having a thickness of 30 μm was pasted.

Production of Support 3 As an adhesive used in the step of providing a polyethylene layer on the base paper surface of the support, a mixture of an acrylic copolymer (SK Dyne 1310, manufactured by Soken Chemical Co., Ltd.), an epoxy resin, and ethyl acetate is 3 g / m ^2. After application, a commercially available polyester film having a thickness of 30 μm was attached.
As described above, Supports 1 to 3 were obtained.

(Emulsion creation)
Emulsified dispersion A was prepared by the following procedure. The compound A-6 described later was dissolved in 42 g of a high boiling point solvent (Solv-1) and 20 ml of ethyl acetate, and this solution was added to 250 g of a 20% by weight gelatin aqueous solution containing 1 g of sodium dodecylbenzenesulfonate with a high-speed stirring emulsifier ( Emulsified and dispersed with a dissolver, and water was added to prepare 380 g of Emulsion A.
The amount of compound A-6 added was 30 mmol in the emulsion A.

(Creation of image receiving sheet)
On the support prepared as described above, a multi-layer coating composition having a constitution of an undercoat layer 1, an undercoat layer ( undercoat layer 2 ) , a heat insulating layer and an image receiving layer was prepared in order from the lower layer . The composition and coating amount of the coating solution are shown below.

Undercoat layer 1 coating liquid (composition)
-Gelatin 3% aqueous solution with 1% sodium dodecylbenzenesulfonate added.
-Adjust pH to 8 with NaOH (application amount) 11 ml / m ²

Underlayer ( undercoat layer 2 ) coating solution (composition)
・ Styrene butadiene latex 60 parts by mass
(SR103 made by Nippon A & L)
-PVA 6% aqueous solution 40 parts by mass-Adjust pH to 8 with NaOH (application amount) 11 ml / m ²

Heat insulation layer coating liquid (composition)
・ Hollow polymer latex 60 mass parts (MH5055, manufactured by Nippon Zeon)
20% by weight of 10% gelatin aqueous solution 20 parts by weight of the previously prepared emulsion A The pH is adjusted to 8 with NaOH (coating amount) 59 ml / m ²

Receiving layer coating liquid (composition)
-70 parts by mass of vinyl chloride acrylic copolymer latex (Brand name Vinibrand 900, manufactured by Nissin Chemical Industry Co., Ltd.)
10% gelatin aqueous solution 10 parts by weight Emulsified A 10 parts previously prepared Microcrystalline wax 5 parts by weight
(Nippon Wax Co., Ltd. EMUSTAR-42X)
-5 parts by weight of water-Adjust pH to 8 with NaOH (application amount) 18 ml / m ²

Preparation Samples 101 to 103 Samples 101 to 106, the lower coating layer 1, the base layer from the bottom on a support in this order (lower coating layer 2), a three-layer structure of the receptor layer, subbing layer 1 and the base layer (under the coating amount of the coating layer 2) is 11 ml / ^{m 2,} the coating amount of the receiving layer was prepared by performing an adjustment to multilayer coating so that 18 ml / ^{m 2.} Samples 104 to 106 were constructed in which a heat insulating layer between the base layer (lower coating layer 2) receiving layer, prepared by performing a multilayer coating by adjusting the coating amount of the heat insulating layer so that 45 ml / m ² did.
(Image formation)
An ink sheet and receiving image sheet of the sample 101 to 106 of the reference example, processed so as to be loaded into Nidec Copal Co., Ltd. sublimation printer DPB1500 (trade name), from the lowest concentration at a high speed print mode The image was output at a setting that could obtain gray gradation in the entire area up to the maximum density. In this case, it took 13 seconds to output one L-size print.

(Dmax evaluation)
The Visual density of the black image obtained under the above conditions was measured with a Photographic Densitometer (manufactured by X-Rite Incorporated). The maximum concentration Dmax was evaluated.

(Equipment contamination)
After the process of outputting gray gradation with the DPB 1500 machine was repeated 10,000 times, black solid output was performed and the number of image defects was counted. By processing a large number of sheets, the pinch roller and platen roller inside the machine were dirty, and image defects increased. The number of image defects per L size was counted.
The obtained results are shown in Table 2 below.

As is clear from the results shown in Table 2, the sample No. It was found that No. 104 had a high Dmax concentration and low equipment contamination.

Claims (15)

On the support, there is at least one receiving layer containing a polymer latex of a copolymer of vinyl chloride and alkyl acrylate, and microcrystalline wax as a release agent , and between the receiving layer and the support A heat-sensitive transfer image-receiving sheet having at least one heat-insulating layer containing a non-foamed hollow polymer latex having a particle size of 0.1 to 2 μm and formed of styrene-acrylic resin, Between the supports, there is a base layer in contact with the heat-insulating layer, and all layers including the base layer and above the base layer contain latex, and the support has an adhesive on both sides of the base paper. A heat-sensitive transfer image-receiving sheet, which is a support provided with a polyethylene resin layer without intervention. On the support, there is at least one receiving layer containing a polymer latex of a copolymer of vinyl chloride and alkyl acrylate, and microcrystalline wax as a release agent , and between the receiving layer and the support A heat-sensitive transfer image-receiving sheet having at least one heat-insulating layer containing a non-foamed hollow polymer latex having a particle size of 0.1 to 2 μm and formed of styrene-acrylic resin, Between the supports, there is a base layer in contact with the heat-insulating layer, and all layers including the base layer and above the base layer contain latex, and the support has an adhesive on both sides of the base paper. A heat-sensitive transfer image-receiving sheet, which is a support having a polyethylene resin layer provided without intervening and having at least two polyethylene resin layers on the receiving layer side.   The heat-sensitive transfer image-receiving sheet according to claim 1, further comprising at least two polyethylene resin layers on both surfaces of the support.   The heat-sensitive transfer image-receiving sheet according to any one of claims 1 to 3, wherein the polyethylene resin opposite to the receiving layer on the support is a blend of high-density polyethylene and low-density polyethylene.   The heat-sensitive transfer image-receiving sheet according to any one of claims 1 to 4, wherein the polyethylene resin on the receiving layer side on the support is a blend of high-density polyethylene and low-density polyethylene.   The thermal transfer image-receiving sheet according to any one of claims 1 to 5, wherein the base layer, the heat insulating layer, and the receiving layer on the polyethylene resin layer are formed by simultaneous multilayer coating.   The heat-sensitive transfer image-receiving sheet according to any one of claims 1 to 6, wherein the heat-insulating layer contains a water-soluble polymer.   The thermal transfer image-receiving sheet according to any one of claims 1 to 6, wherein the heat-insulating layer contains gelatin.   The thermal transfer image-receiving sheet according to any one of claims 1 to 8, wherein the heat insulating layer contains the hollow polymer latex and a binder resin, and the binder resin is only a water-soluble polymer.   The thermal transfer image-receiving sheet according to any one of claims 1 to 8, wherein the heat insulating layer contains the hollow polymer latex and a binder resin, and the binder resin is only gelatin.   The heat-sensitive transfer image-receiving sheet according to claim 1, wherein the receiving layer contains gelatin. The heat-sensitive transfer image-receiving sheet according to any one of claims 1 to 1 1, characterized in that it contains an image hardening agent or an ultraviolet absorber into the receiving layer. The heat-sensitive transfer image-receiving sheet according to any one of claims 1 to 12 , wherein the heat-insulating layer contains an image fastening agent or an ultraviolet absorber. The thermal transfer image-receiving sheet according to any one of claims 1 to 11, wherein the receptor layer contains an emulsion containing an image fastening agent or an ultraviolet absorber. The heat-sensitive transfer image-receiving sheet according to any one of claims 1 to 12 , wherein the heat-insulating layer contains an emulsion containing an image fastening agent or an ultraviolet absorber.