JP2008030450A - Thermosensitive transfer image receiving sheet - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a thermosensitive transfer image receiving sheet, which has high productivity and excellent environmental safety, is highly sensitive, highly dense and is excellent in a long-term storage stability and can form a high image quality image. <P>SOLUTION: This thermosensitive transfer image receiving sheet includes at least one receiving layer including polymer latex, in the polymer of which ≥50 mass% of repeating unit obtained from vinyl chloride is contained, and at least one heat insulating layer including a hollow polymer latex and a water-soluble polymer between the receiving layer and the support. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a thermal transfer image receiving sheet.

  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 such a dye diffusion transfer type recording system, in order to obtain a good image, 1) the image receiving sheet has a high heat insulating property and cushioning property, and 2) a receiving layer having a high affinity for the dye is used. It has been known that it is important (see, for example, Non-Patent Documents 1 and 2).
In order to provide heat insulation and cushioning properties, a composite support in which a biaxially stretched polyolefin film containing microvoids is bonded to a core material layer such as paper may be used as a base material of an image receiving sheet (for example, Patent Documents). 1, 2). However, this method has drawbacks such as low productivity and high cost because the receiving layer is coated with a solvent after the bonding step.
On the other hand, as another method for imparting heat insulation and cushioning properties to the image receiving sheet, a porous layer containing a foamed layer (for example, Patent Document 3) made of a resin and a foaming agent or a hollow polymer between the support and the receiving layer, for example. A method of forming a layer having high cushioning properties such as a quality layer (for example, Patent Document 4) is also known. Since these methods can form a heat insulating layer on a substrate by a coating method, a laminating step is necessary for a method using a composite support using a biaxially stretched polyolefin film containing the microvoids. There is an advantage that it disappears.
However, in these techniques (Patent Documents 3 and 4), the heat-insulating layer is applied in water, but the receiving layer is formed by solvent application. Polyester resins, vinyl chloride resins, polycarbonate resins, and the like are known as polymers having a high affinity for pigments used as the receiving layer (for example, Patent Documents 5, 6, and 7). Many of the methods for producing these receiving layers are solvent coating, and no aqueous latex polymer latex has been implemented. Accordingly, the heat-sensitive transfer image-receiving sheet must be produced in water, and after application of the heat-insulating layer, it must inevitably be subjected to application of the receiving layer and sequential application of the solvent, which is not sufficient from the viewpoint of productivity.
On the other hand, in the silver salt photography industry, it is known that productivity is greatly improved by simultaneously applying a plurality of layers having different functions on a support to an aqueous multilayer (Patent Document 8, Non-Patent Document). 3). In addition, it has recently been proposed that a thermal transfer image-receiving sheet is simultaneously coated with multiple layers (Patent Document 9). Aqueous multi-layer coating is preferable to solvent coating in terms of productivity, air pollution, fire hazard, occupational hygiene, etc., but there are many points to be overcome, and it is more dyeable than before. There is a demand for a heat-sensitive transfer image-receiving sheet that is high, has sufficient sensitivity and maximum density, and has good releasability (does not adhere) between the ink sheet and the heat-sensitive transfer image-receiving sheet.

US Pat. No. 866,282 JP-A-3-268998 Japanese Patent No. 2554196 Japanese Patent Laid-Open No. 2006-82382 Japanese Patent Application Laid-Open No. 61-283595 JP-A-5-209118 JP-A-6-227160 JP-A-63-54975 JP 2006-88691 A “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 Edgar B. Gutoff et al., “Coating and Drying Defects: Troubleshooting Operating Problems”, John Wiley & Sons, 1995, pages 101-103.

  The present invention provides a thermal transfer image-receiving sheet having high productivity, excellent safety and environmental aspects, high sensitivity and high density, and good (non-adhering) releasability between the ink sheet and the thermal transfer image-receiving sheet. The purpose is to provide. Another object of the present invention is to provide a heat-sensitive transfer image-receiving sheet having excellent long-term storage stability.

As a result of intensive studies, the present inventors have achieved the above-described problem by the following means.
(1) It has at least one receiving layer containing a polymer latex containing 50% by mass or more of a repeating unit obtained from vinyl chloride on a support, and at least 1 is provided between the receiving layer and the support. A heat-sensitive transfer image-receiving sheet comprising a layer of a hollow polymer latex and a heat insulating layer containing a water-soluble polymer.
(2) The heat-sensitive transfer image-receiving sheet as described in (1), wherein the polymer latex of the receiving layer is a copolymer with acrylic acid esters.
(3) The heat-sensitive transfer image-receiving sheet as described in the item (2), wherein the polymer latex of the receiving layer is a copolymer with at least two kinds of acrylic esters.
(4) The heat-sensitive transfer image-receiving sheet as described in (2) or (3), wherein the alcohol part of the acrylic ester has 1 to 8 carbon atoms.
(5) The number of carbon atoms in the alcohol part of the acrylic ester is 1 and 10 to 45% by mass of a repeating unit obtained from the acrylic ester is contained in the copolymer (2) The thermal transfer image-receiving sheet according to any one of to (4).
(6) The number of carbon atoms in the alcohol part of the acrylate ester is 2, and the copolymer contains 5 to 45% by mass of a repeating unit obtained from the acrylate ester (2) The thermal transfer image-receiving sheet according to any one of to (4).
(7) The number of carbon atoms in the alcohol part of the acrylate ester is 3, and the copolymer contains 5 to 35% by mass of a repeating unit obtained from the acrylate ester (2) The thermal transfer image-receiving sheet according to any one of to (4).
(8) The number of carbon atoms in the alcohol part of the acrylic ester is 4 and 4 to 30% by mass of a repeating unit obtained from the acrylic ester is contained in the copolymer (2) The thermal transfer image-receiving sheet according to any one of to (4).
(9) The number of carbon atoms in the alcohol part of the acrylate ester is 6 and the copolymer contains 3 to 28% by mass of repeating units obtained from the acrylate ester (2) The thermal transfer image-receiving sheet according to any one of to (4).
(10) The number of carbon atoms in the alcohol part of the acrylate ester is 8, and the copolymer contains 2 to 25% by mass of a repeating unit obtained from the acrylate ester (2) The thermal transfer image-receiving sheet according to any one of to (4).
(11) The thermal transfer image-receiving sheet according to any one of (1) to (10), wherein the polymer latex of the receiving layer is a copolymer with vinyl acetate.
(12) The thermal transfer image-receiving sheet as described in (11), wherein the copolymer contains 3 to 30% by mass of a repeating unit obtained from vinyl acetate.
(13) The heat-sensitive transfer image-receiving sheet as described in (1), wherein the polymer latex of the receiving layer is a copolymer of vinyl chloride, at least one of acrylic esters and vinyl chloride.
(14) The heat-sensitive transfer image-receiving sheet described in any one of (1) to (13) is manufactured by simultaneously applying the receiving layer and the heat insulating layer in the manufacturing process. Thermal transfer image-receiving sheet.

  According to the present invention, it is possible to provide a thermal transfer image-receiving sheet having high productivity, excellent environment and safety, high sensitivity, high density, excellent long-term storage, and capable of forming a high-quality image.

Hereinafter, the present invention will be described in detail.
First, the thermal transfer image receiving sheet used in the present invention will be described.
The heat-sensitive transfer image-receiving sheet used in the present invention has at least a dye receiving layer (receiving layer) and a heat insulating layer formed on a support. A base layer is preferably formed between the receptor layer and the support. For example, a white background adjustment layer, a charge adjustment layer, an adhesive layer, and a primer layer are formed. Moreover, it is preferable that the heat insulation layer is formed between the base layer and the support body. Furthermore, a curl adjusting layer, a writing layer, and a charge adjusting layer are preferably formed on the back side of the support. Each layer is applied by a general method such as roll coating, bar coating, gravure coating, gravure reverse coating, die coating, slide coating, curtain coating, etc., but multiple layers such as slide coating, curtain coating, etc. are applied simultaneously in multiple layers. Preferred is a method that can

(Receptive layer)
The receiving layer serves to receive the dye transferred from the ink sheet and maintain the formed image. The image-receiving sheet used in the present invention has at least one receiving layer having a thermoplastic receiving polymer capable of receiving at least a dye.
The accepting polymer is preferably used as a polymer latex dispersed in a water-soluble dispersion medium. Furthermore, the receiving layer preferably contains a water-soluble polymer in addition to the polymer latex. By containing a polymer latex and a water-soluble polymer, a water-soluble polymer that is difficult to be dyed on the dye can be present between the polymer latexes, and the dye dyed on the polymer latex can be prevented from diffusing. Thus, it is possible to reduce a change in sharpness of the receiving layer with time and to form a recorded image with a small change in transfer image with time.
For the receiving layer, in addition to the polymer latex of the receiving polymer, for example, a polymer latex having other functions can be used in combination for the purpose of adjusting the elastic modulus of the film.

<Polymer latex>
The polymer latex used in the present invention will be described.
Common polymer latices are described in 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, “Synthetic Latex Chemistry”, published by Kobunshi Shuppankai (1970), supervised by Yoshiaki Mitsawa, “Development and Application of Water-Based Coating Materials”, CMC Publishing (2004) and JP Sho 64-538.
The polymer latex that can be used in the receiving layer in the heat-sensitive transfer image-receiving sheet of the present invention is obtained by dispersing a water-insoluble hydrophobic polymer as fine particles in a water-soluble dispersion medium. Several different types of polymer latex may be used in combination as the polymer latex, but the polymer latex used in the present invention includes at least vinyl chloride as a monomer unit, that is, includes a repeating unit obtained from vinyl chloride, The proportion of vinyl chloride units in the total polymer in the receiving layer is preferably 50% by mass or more. More preferably, it is 65 mass% or more, More preferably, it is 70-95 mass%.

  In the synthesis of latex containing vinyl chloride as a monomer unit used in the present invention, other monomers used in combination with vinyl chloride monomer are not particularly limited and can be polymerized by ordinary radical polymerization or ionic polymerization. The monomer groups (a) to (j) shown below can be preferably used. Polymer monomers can be synthesized by selecting these monomers independently and freely in combination.

-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, etc. Among these, acrylic acid esters and methacrylic acid esters are preferable.

(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-acryloyl morpholine, 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.

  As a preferred embodiment of the polymer latex containing a repeating unit obtained from vinyl chloride used in the receiving layer in the present invention, a copolymer containing vinyl chloride as a monomer unit is used. The monomer copolymerized with the vinyl chloride monomer unit is preferably the above (b), (c), (e), (g), (i) or (h), and (c) and (h) Is more preferable. Of these, acrylates and vinyl esters are preferable, acrylates having 1 to 8 carbon atoms in the alcohol portion, and vinyl acetate are preferable, and acrylate esters having 1 to 8 carbon atoms in the alcohol portion are particularly preferable. It is kind.

  As the monomer copolymerizable with the vinyl chloride monomer unit, one type may be used, or two or more types may be used in combination. Among such copolymers, vinyl chloride-vinyl acetate copolymer, vinyl chloride-acrylic acid ester copolymer, vinyl chloride-acrylic acid ester-acrylic acid ester (an ester different from the former) are preferable. A terpolymer, a vinyl chloride-vinyl acetate-acrylic acid ester ternary copolymer, and more preferably a vinyl chloride-acrylic acid ester copolymer. In this case, the ratio of the vinyl chloride monomer is preferably 50% or more and 98% or less.

Regarding the vinyl chloride-acrylic acid ester copolymer latex used in the present invention, the number of carbons of the alcohol part of the acrylic acid esters is not particularly limited, but 1, 2, 3, 4, 6, 8 are preferred, 3, 4 are more preferable, and 2, 4 are most preferable.
The vinyl chloride-acrylic acid ester copolymer latex is appropriately selected from the viewpoints of dye transferability during image formation, adhesion to an ink sheet, or ease of handling during coating. These performances are generally selected according to the glass transition temperature (Tg) of the latex. For example, a lower Tg is generally preferable for dye transferability, and a higher Tg is better for adhesion to an ink ribbon. It is difficult and preferable. Regarding the handling property at the time of coating, it is known that a higher Tg is less likely to generate a skin burr and is preferably used.
Here, it has been found that a copolymer of vinyl chloride-acrylic acid ester having 4 carbon atoms in the alcohol part is superior in transferability to other vinyl chloride-acrylic acid ester copolymers having the same Tg and can be preferably used. It came to make this invention.
When the copolymer of vinyl chloride-acrylic acid ester having 2 carbon atoms in the alcohol part is coated more than other vinyl chloride-acrylic acid ester copolymers having the same Tg to form an image receiving sheet for a sublimation printer, The present inventors have found that a preferable surface shape can be obtained, and have arrived at the present invention.

  In the vinyl chloride-acrylic acid ester copolymer latex, the preferred proportion of the acrylic acid ester repeating unit to be closed is 10% by mass or more and 50% by mass or less when the carbon number of the alcohol part is 1, and more preferably 15%. It is at least 40% by mass and most preferably at least 20% and not more than 35%.

  When the number of carbon atoms in the alcohol part is 2, the ratio of the preferred acrylic ester repeating unit closing is 5% by mass or more and 45% by mass or less, more preferably 10% by mass or more and 40% by mass or less, and most preferably. Is 20 mass% or more and 30 mass% or less.

  When the number of carbon atoms in the alcohol part is 3, the ratio of the preferred acrylic acid ester repeating unit closing is 5% by mass or more and 35% by mass or less, more preferably 10% by mass or more and 30% by mass or less, and most preferably. Is 15 mass% or more and 25 mass% or less.

  When the number of carbon atoms in the alcohol part is 4, the preferred proportion of the acrylic ester repeating unit to be closed is 4% by mass or more and 30% by mass or less, more preferably 5% by mass or more and 25% by mass or less, and most preferably. Is 8 mass% or more and 20 mass% or less.

  When the alcohol part has 6 carbon atoms, the preferred proportion of the acrylic ester repeating unit to be closed is 3% by mass or more and 28% by mass or less, more preferably 5% by mass or more and 25% by mass or less, and most preferably. Is 7 mass% or more and 20 mass% or less.

  When the alcohol part has 8 carbon atoms, the preferred proportion of the acrylic ester repeating unit to be closed is 2% by mass or more and 28% by mass or less, more preferably 4% by mass or more and 25% by mass or less, and most preferably. Is 6 mass% or more and 20 mass% or less.

  In the vinyl chloride-vinyl acetate copolymer latex, the preferred closing ratio of the vinyl acetate repeating unit is 3% by mass or more and 30% by mass or less, more preferably 5% by mass or more and 25% by mass or less, and most preferably 8%. The mass is 20% by mass or more.

  Vinyl chloride-acrylic acid ester-acrylic acid ester (an ester different from the former) is preferable in a terpolymer latex (acrylic acid ester-acrylic acid ester (an ester different from the former)) The proportion of repeating units is 2% by mass Above, it is 45 mass% or less.

  Preferred in vinyl chloride-vinyl acetate-acrylic acid ester terpolymer latex (vinyl acetate-acrylic acid ester) The proportion of repeating units is 2% by mass or more and 45% by mass or less.

These polymers may be linear polymers, branched polymers, or crosslinked polymers. 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 1,000,000, 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.
The average particle size of the dispersed particles is preferably 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. Such an average particle diameter can be measured with SUB-MICRON PARTICLE ANALYZER (trade name, MODEL N4SD, manufactured by COULTER).

  There are no particular restrictions on polymer latexes having other structures used in combination with polymer latexes containing repeating units derived from vinyl chloride, but acrylic polymers, polyesters, rubbers (eg SBR resins), polyurethanes , Hydrophobic polymers such as polyvinyl chlorides, polyvinyl acetates, polyvinylidene chlorides and polyolefins 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 1,000,000, 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.

  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 used in 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.

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. The homopolymer glass transition temperature value (Tgi) of each monomer may be the value of “Polymer Handbook (3rd Edition)” (by J. Brandrup, EH Immergut (Wiley-Interscience, 1989)).

  The polymer latex having another structure used in combination with the latex containing the monomer unit of vinyl chloride used in the present invention has a glass transition temperature (Tg) of −30 ° C. to 100 in terms of processing brittleness and image storage stability. The thing of the range of ° C is preferable, More preferably, it is the range of 0 degreeC-80 degreeC, More preferably, it is the range of 20 degreeC-70 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.

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 polymer latex. For example, Soichi Muroi, “Chemistry of Synthetic Latex”, published by Kobunshi Shuppankai (1970) )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

  Polymer latex containing a repeating unit obtained from vinyl chloride that can be used in the present invention is commercially available, and the following polymers can be used. Examples include G351 and G576 manufactured by Nippon Zeon Co., Ltd., Vinibrand 240, 270, 277, 375, 386, 609, 550, 601, 602, 630, 660, 671, 683, 680 manufactured by Nissin Chemical Industry Co., Ltd. 680S, 681N, 685R, 277, 380, 381, 410, 430, 432, 860, 863, 865, 867, 900, 900GT, 938, 950, etc. (all are trade names).

  Polymer latexes having other structures used in combination with polymer latexes containing repeating units obtained from vinyl chloride are also commercially available and can be used in combination. Examples of the acrylic polymer include: Sebian A-4635, 4718, 4601 manufactured by Daicel Chemical Industries, Ltd., Nipol Lx811, 814, 821, 820, 855 manufactured by Nippon Zeon Co., Ltd. (P-17: Tg 36 ° C.), 857 × 2 (P-18: Tg43 ° C), Voncoat R3370 (P-19: Tg25 ° C), 4280 (P-20: Tg15 ° C), manufactured by Dainippon Ink & Chemicals, Jurimer ET-410 (manufactured by Nippon Pure Chemical Co., Ltd.) P-21: Tg 44 ° C.), AE116 (P-22: Tg 50 ° C.) manufactured by JSR Corporation, AE119 (P-23: Tg 55 ° C.), AE121 (P-24: Tg 58 ° C.), AE125 (P-25: Tg 60) ° C), AE134 (P-26: Tg48 ° C), AE137 (P-27: Tg48 ° C), AE140 (P-28: Tg53 ° C), AE17 (P-29: Tg 60 ° C.), Aron A-104 (P-30: Tg 45 ° C.) manufactured by Toagosei Co., Ltd., NS-600X, NS-620X manufactured by Takamatsu Yushi Co., Ltd., manufactured by Nissin Chemical Industry Co., Ltd. Vinibrand 2580, 2583, 2641, 2770, 2770H, 2635, 2886, 5202C, 2706, etc. (all are trade names).

  Examples of polyesters include: Finetex EX650, 611, 675, 850 manufactured by Dainippon Ink Chemical Co., Ltd., WD-size, WMS manufactured by Eastman Chemical, A-110, A-115GE manufactured by Takamatsu Yushi Co., Ltd., 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, N -140L, NS-141LX, NS-282LX, Toagosei Co., Ltd. Aron Melt PES-1000 series, PES-2000 series, Toyobo Co., Ltd. Bironal MD-1100, MD-1200, MD-1220, MD-1245, Examples thereof include MD-1250, MD-1335, MD-1400, MD-1480, MD-1500, MD-1930, MD-1985, and Sephorjon ES manufactured by Sumitomo Seika Co., Ltd. (all are trade names).

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

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

  Examples of polyolefins include Chemipearl S120, SA100, V300 (P-40: Tg 80 ° 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 copolymer nylons include Sepoljon PA manufactured by Sumitomo Seika Co., Ltd. (all are trade names).

  Examples of polyvinyl acetates include Nibsin Chemical Industry Co., Ltd., Vinibrand 1080, 1082, 1085W, 1108W, 1108S, 1563M, 1566, 1570, 1588C, A22J7-F2, 1128C, 1137, 1138, A20J2, A23J1, A23J1, A23K1, A23P2E, A68J1N, 1086A, 1086A, 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, 1 07L, 1225,1245L, GV-6170, GV-6181,4468W, such as the 4468S, and the like (all trade names).

These polymer latexes may be used alone or in combination of two or more as required.
In the receiving layer in the present invention, the polymer latex containing vinyl chloride as a monomer unit is preferably 50% or more in terms of the total solid content in the layer.

  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.

  The polymer latex used in the present invention can be easily obtained by a solution polymerization method, a suspension polymerization method, an emulsion polymerization method, a dispersion polymerization method, an anionic polymerization method, a cationic polymerization or the like. 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 Press (1978), Takaaki Sugimura, Akio Kataoka, Junichi Suzuki, Keiji Kasahara, “Application of Synthetic Latex”, Published by Polymer Press (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. The 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. -73645, JP-A-4-127145, JP-A-4-247703, JP-A-4-305572, JP-A-6-11805, JP-A-5-1773312, JP-A-5-66527, JP-A-5-67527. 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 May JP 8-314090, JP-A-10-182571, JP-A-10-182570, can be used the compounds described in JP or the specification of JP-A-11-190892.

  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, 57-17943, 54-61125 and West German Patent No. 1045373, or the like), a polyphenol chelating agent Preferably such polyamine chelating compounds, with 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′-four Acetic 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, cyclohexane-1,3-diamine-N, N, N ′, N′-four 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′-tetraacetic 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 sodium or potassium Substituted ones such as alkali metal salts and 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.

The polymer latex used in the present invention 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.
In addition, the polymer latex in the image-receiving sheet used in the present invention includes a gel or a dried film 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.
In the present invention, a water-soluble polymer may be labeled as a binder to distinguish it from 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. Examples of plant polysaccharides include gum arabic, κ-carrageenan, ι-carrageenan, λ-carrageenan, guar gum (such as Supercol from Squalon), locust bean gum, pectin, tragacanth, and corn starch (Purity- from National Starch & Chemical Co.). 21), phosphorylated starch (National Star & Chemical Co., National 78-1898, etc.) and the like, and microbial polysaccharides such as xanthan gum (Kelco, Keltrol T), dextrin (National Star & Chemical Co., Ndex 360, etc.) ) And other animal-based natural polymers such as gelatin (Crodine B419 from Croda), casein Such as sodium chondroitin sulfate (such as Croda made Cromoist CS), and the like (all trade names). Cellulose-based materials include ethyl cellulose (ICF Cellofas WLD, etc.), carboxymethyl cellulose (Daicel CMC, etc.), hydroxyethyl cellulose (Daicel HEC, etc.), hydroxypropyl cellulose (Aqualon Klucel, etc.), and methyl cellulose (Henkel). Viscontran, etc.), nitrocellulose (Isopropyl Wet, etc. from Hercules), cationized cellulose (Crodacel QM, etc. from Croda), etc. (all are trade names). As starch systems, phosphorylated starch (such as National Star & Chemical National 78-1898), alginic acid systems such as sodium alginate (such as Kelco's Keltone), propylene glycol alginate, and other classifications include cationized guar gum (Alcolac). Hi-care 1000, etc.) and sodium hyaluronate (Hyalure, etc. from Lifecare Biomedical) (all are trade names).
In the present invention, gelatin is one of the preferred embodiments. The gelatin used in the present invention may have a molecular weight of 10,000 to 1,000,000. Gelatin used in the present invention may contain anions such as Cl ⁻ , SO ₄ ²⁻ , and cations such as Fe ²⁺ , Ca ²⁺ , Mg ²⁺ , Sn ²⁺ and Zn ^2+. It may be included. It is preferable to add gelatin dissolved in water.

  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 alcohols are preferred.
Hereinafter, 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 is 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 Publications published 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 addition amount of boric acid is preferably 0.01 to 40% by mass with respect 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.

<Hardener>
The hardening agent used in the present invention as a crosslinking agent can be added to a coating layer (for example, a receiving layer, a heat insulating layer, a subbing layer, etc.) of the image receiving sheet.
Examples of the hardening agent that can be used in the present invention include H-1,4,6,8,14 on page 17 of JP-A-1-214845, column 13 to U.S. Pat. No. 4,618,573. 23 compounds (H-1 to 54) represented by formulas (VII) to (XII), compounds (H-1 to 76) represented by formula (6) on page 8, lower right of JP-A-2-214852, In particular, H-14 and the compounds described in claim 1 of US Pat. No. 3,325,287 are preferably used. Examples of hardeners are US Pat. No. 4,678,739, column 41, US Pat. No. 4,791,042, JP-A Nos. 59-116655, 62-245261, and 61-18842. And the hardening agent described in JP-A-4-218444 or the specification thereof. More specifically, aldehyde hardeners (formaldehyde, etc.), aziridine hardeners, epoxy hardeners, vinyl sulfone hardeners (N, N′-ethylene-bis (vinylsulfonylacetamide) Ethane), N-methylol hardeners (dimethylolurea, etc.), boric acid, metaboric acid, or polymer hardeners (compounds described in JP-A-62-234157).
Preferably, a vinyl sulfone type hardener and chlorotriazines are used.
More preferable hardeners in the present invention are compounds represented by the following general formula (B) or (C).
General formula (B)
_{(CH 2 = CH-SO 2} ) n-L
General formula (C)
(X—CH ₂ —CH ₂ —SO ₂ ) nL
In general formulas (B) and (C), X represents a halogen atom, and L represents an n-valent organic linking group. When the compound represented by formula (B) or (C) is a low molecular compound, n represents an integer of 1 to 4. In the case of a polymer compound, L is an organic linking group containing a polymer chain, and n is in the range of 10 to 1000.

  In the general formulas (B) and (C), X is preferably a chlorine atom or a bromine atom, more preferably a bromine atom. n is an integer of 1 to 4, preferably an integer of 2 to 4, more preferably an integer of 2 to 3, and most preferably 2.

  L represents an n-valent organic group, preferably an aliphatic hydrocarbon group, an aromatic hydrocarbon group or a heterocyclic group, and these groups are ether bond, ester bond, amide bond, sulfonamide bond, urea bond, It may be further connected with a urethane bond or the like. These groups may have a substituent, such as a halogen atom, alkyl group, aryl group, heterocyclic group, hydroxyl group, alkoxy group, aryloxy group, alkylthio group, arylthio group, acyloxy group, alkoxycarbonyl. Groups, carbamoyloxy groups, acyl groups, acyloxy groups, acylamino groups, sulfonamido groups, carbamoyl groups, sulfamoyl groups, sulfonyl groups, phosphoryl groups, carboxyl groups, sulfo groups, etc., halogen atoms, alkyl groups, hydroxy groups, Alkoxy groups, aryloxy groups and acyloxy groups are preferred.

  Specific examples of the vinyl sulfone hardener include the following (VS-1) to (VS-27), but are not limited to these in the present invention.

These hardeners can be obtained by referring to the method described in US Pat. No. 4,173,481.
As the chlorotriazine hardener, a 1,3,5-triazine compound in which at least one chloro atom is substituted at the 2-position, 4-position or 6-position is preferable.
More preferred are those in which 2 or 3 chlorine atoms are substituted at the 2nd, 4th or 6th position. At least one chlorine atom may be substituted at the 2-position, 4-position or 6-position, and a group other than a chlorine atom may be substituted at the remaining positions. Examples of these groups include a hydrogen atom, a bromine atom, Fluorine atom, iodine atom, alkyl group, alkenyl group, alkynyl group, cycloalkyl group, cycloalkenyl group, aryl group, heterocyclic group, hydroxy group, nitro group, cyano group, amino group, hydroxylamino group, alkylamino group, Arylamino group, heterocyclic amino group, acylamino group, sulfonamido group, carbamoyl group, sulfamoyl group, sulfo group, carboxyl group, alkoxy group, alkenoxy group, aryloxy group, heterocyclic oxy group, acyl group, acyloxy group, alkyl Or arylsulfonyl group, alkyl or arylsulfinyl group, alkyl Ku is arylsulfonyloxy group, a mercapto group, an alkylthio group, an alkenylthio group, an arylthio group, a heterocyclic thio group, such as alkyloxy or aryloxy carbonyl group.
Specific examples of chlorotriazine hardeners include 4,6-dichloro-2-hydroxy-1,3,5-triazine or its Na salt, 2-chloro-4,6-diphenoxytriazine, 2-chloro. -4,6-bis [2,4,6-trimethylphenoxy] triazine, 2-chloro-4,6-diglycidoxy-1,3,5-triazine, 2-chloro-4- (n-butoxy) -6 Glycidoxy-1,3,5-triazine, 2-chloro-4- (2,4,6-trimethylphenoxy) -6-glycidoxy-1,3,5-triazine, 2-chloro-4- (2-chloroethoxy ) -6- (2,4,6-trimethylphenoxy) 1,3,5-triazine, 2-chloro-4- (2-bromoethoxy) -6- (2,4,6-trimethylphenoxy) -1, 3,5-tri 2-chloro-4- (2-di-n-butylphosphatoethoxy) -6- (2,4,6-trimethylphenoxy) -1,3,5-triazine, 2-chloro-4- (2 -Di-n-butylphosphatoethoxy) -6- (2,6-xylenoxy) -1,3,5-triazine and the like, but not limited thereto.
Such a compound can be easily produced by reacting cyanuric chloride (that is, 2,4,6-trichlorotriazine) with a hydroxy compound, a thio compound or an amino compound corresponding to a substituent on the heterocyclic ring.

  These hardeners are used in an amount of 0.001 to 1 g, preferably 0.005 to 0.5 g, per 1 g of water-soluble polymer.

<Emulsions>
The receiving layer of the heat-sensitive transfer image-receiving sheet used in the present invention preferably contains an emulsion. The emulsion preferably used in the present invention will be described below.
Hydrophobic additives such as lubricants and antioxidants can be obtained by a known method such as the method described in US Pat. No. 2,322,027, such as a layer of an image receiving sheet (for example, a receiving layer, a heat insulating layer, an undercoat layer, etc.). ) Can be introduced in. In this case, U.S. Pat. Nos. 4,555,470, 4,536,466, 4,536,467, 4,587,206, 4,555,476 No. 4,599,296, JP-B-3-62256, or a high boiling point organic solvent described in the specification or the like, if necessary, in combination with a low boiling point organic solvent having a boiling point of 50 ° C. to 160 ° C. Can be used. These lubricants, antioxidants, high-boiling organic solvents and the like can be used in combination of two or more.

  As the antioxidant (hereinafter also referred to as a radical scavenger), a compound represented by any one of the following general formulas (E-1) to (E-3) is preferably used.

R ₄₁ is an aliphatic group, aryl group, heterocyclic group, acyl group, aliphatic oxycarbonyl group, aryloxycarbonyl group, aliphatic sulfonyl group, arylsulfonyl group, phosphoryl group, or —Si (R ₄₇ ) (R ₄₈ ). (R ₄₉ ) is represented. Here, R ₄₇ , R ₄₈ and R ₄₉ each independently represents an aliphatic group, an aryl group, an aliphatic oxy group or an aryloxy group. R ₄₂ , R ₄₃ , R ₄₅ and R ₄₆ represent a hydrogen atom or a substituent. Examples of the substituent include halogen atoms, aliphatic groups (including alkyl groups, alkenyl groups, alkynyl groups, cycloalkyl groups, and cycloalkenyl groups), aryl groups, heterocyclic groups, hydroxy groups, mercapto groups, aliphatic oxy groups. Group, aryloxy group, heterocyclic oxy group, aliphatic thio group, arylthio group, heterocyclic thio group, amino group, aliphatic amino group, arylamino group, heterocyclic amino group, acylamino group, sulfonamide group, cyano group Nitro group, carbamoyl group, sulfamoyl group, acyl group, aliphatic oxycarbonyl group, aryloxycarbonyl group and the like. R _{a1 to} R _a4 each independently represents a hydrogen atom or an aliphatic group (for example, methyl, ethyl).
With respect to the compound represented by any one of the general formulas (E-1) to (E-3), preferred substituents in terms of the effects of the present invention will be described.
In the general formulas (E-1) to (E-3), R ₄₁ is an aliphatic group, an acyl group, an aliphatic oxycarbonyl group, an aryloxycarbonyl group, or a phosphoryl group, and R ₄₂ , R ₄₃ , R ₄₅ And R ₄₆ are each independently preferably a hydrogen atom, an aliphatic group, an aliphatic oxy group or an acylamino group, R ₄₁ is an aliphatic group, and R ₄₂ , R ₄₃ , R ₄₅ and R ₄₆ are It is more preferable that each independently represents a hydrogen atom or an aliphatic group.
Although the preferable specific example represented by either of general formula (E-1)-(E-3) below is shown below, this invention is not limited to these.

  The content of the antioxidant is preferably 1.0 to 7.0% by mass, more preferably 2.5 to 5.0% by mass, based on the solid content in the polymer latex.

  Examples of the lubricant include solid waxes such as polyethylene wax, amide wax, and Teflon (registered trademark) powder; silicone oil, phosphate ester compounds, fluorine surfactants, silicone surfactants, and other in the technical field. A known release agent can be used, and a fluorine-based compound represented by a fluorine-based surfactant, a silicone-based surfactant, a silicone oil such as a silicone oil and / or a cured product thereof is preferably used. The content of the lubricant is preferably 1.0 to 10.0% by mass, more preferably 1.5 to 2.5% by mass, based on the solid content in the polymer latex.

  As the silicone oil as the lubricant, straight silicone oil, modified silicone oil and its cured product can be used. Straight silicone oils include dimethyl silicone oil, methylphenyl silicone oil, and methyl hydrogen silicone oil. Examples of dimethyl silicone oil include KF96-10, KF96-100, KF96-1000, KF96H-10000, KF96H-12500, and KF96H. -100,000 (all are trade names, manufactured by Shin-Etsu Chemical Co., Ltd.) and the like, and as dimethyl silicone oil, KF50-100, KF54, KF56 (all are trade names, manufactured by Shin-Etsu Chemical Co., Ltd.), etc. Can be mentioned.

  The modified silicone oil can be classified into a reactive silicone oil and a non-reactive silicone oil. The reactive silicone oil includes amino modification, epoxy modification, carboxyl modification, hydroxy modification, methacryl modification, mercapto modification, phenol modification, one-terminal reactivity and heterofunctional modification. As amino-modified silicone oil, KF-393, KF-857, KF-858, X-22-3680, X-22-3801C, KF-8010, X-22-161A, KF-8012 (all trade names, Shin-Etsu Chemical Co., Ltd.), etc., and epoxy-modified silicone oils include KF-100T, KF-101, KF-60-164, KF-103, X-22-343, X-22-3000T ( All of them are trade names, manufactured by Shin-Etsu Chemical Co., Ltd.). Examples of the carboxyl-modified silicone oil include X-22-162C (trade name, manufactured by Shin-Etsu Chemical Co., Ltd.). Examples of the hydroxy-modified silicone oil include X-22-160AS, KF-6001, KF-6002, KF-6003, X-22-170DX, X-22-176DX, X-22-176D, X-22-176DF (all trade names, manufactured by Shin-Etsu Chemical Co., Ltd.) X-22-164A, X-22-164C, X-24-8201, X-22-174D, X-22-2426 (all are trade names, manufactured by Shin-Etsu Chemical Co., Ltd.) and the like. .

The reactive silicone oil can be used after being cured, and can be classified into a reaction curable type, a photo curable type, a catalyst curable type, and the like. Of these, reaction-curable silicone oils are particularly preferable. As the reaction-curable silicone oils, those obtained by reaction-curing amino-modified silicone oil and epoxy-modified silicone oil are preferable. Further, as the catalyst curable type or photo curable type silicone oil, KS-705F-PS, KS-705F-PS-1, KS-770-PL-3 [catalyst curable type silicone oil: all trade names, Shin-Etsu Chemical Co., Ltd. (
Co., Ltd.], KS-720, KS-774-PL-3 [photocured silicone oil: trade names, manufactured by Shin-Etsu Chemical Co., Ltd.], and the like. The addition amount of these curable silicone oils is preferably 0.5 to 30% by mass of the resin constituting the receiving layer. The release agent is used in an amount of 2 to 4% by mass, preferably about 2 to 3% by mass, based on 100 parts by mass of the polyester resin. If the amount is too small, the releasability cannot be ensured, and if the amount is too large, the protective layer will not be transferred to the image receiving sheet.

  Non-reactive silicone oils include polyether modification, methylstyryl modification, alkyl modification, higher fatty acid ester modification, hydrophilic special modification, higher alkoxy modification, fluorine modification and the like. Examples include polyether-modified silicone (KF-6012, trade name, manufactured by Shin-Etsu Chemical Co., Ltd.), and methylstil-modified silicone silicone oils (24-510, KF41-410, both trade names, Shin-Etsu Chemical ( Etc.). Moreover, the modified silicone represented by either of the following general formulas 1-3 can also be used.

  In General Formula 1, R represents a hydrogen atom, an aryl group, or a linear or branched alkyl group that may be substituted with a cycloalkyl group. m and n represent an integer of 2000 or less, and a and b represent an integer of 30 or less.

  In General Formula 2, R represents a hydrogen atom, an aryl group, or a linear or branched alkyl group which may be substituted with a cycloalkyl group. m represents an integer of 2000 or less, and a and b represent an integer of 30 or less.

In General Formula 3, R represents a hydrogen atom, an aryl group, or a linear or branched alkyl group which may be substituted with a cycloalkyl group. m and n represent an integer of 2000 or less, and a and b represent an integer of 30 or less. R ¹ represents a single bond or a divalent linking group, E represents an ethylene group which may have a substituent, and P represents a propylene group which may have a substituent.

  Silicone oils such as those described above are described in “Silicone Handbook” (published by Nikkan Kogyo Shimbun Co., Ltd.), and are described in JP-A-8-108636 and JP-A-2002-264543 as curing technologies for curable silicone oils. The technique can be preferably used.

High boiling point organic 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 塁 (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, etc.), chlorinated paraffins, hydrocarbons (dode) Rubenzen, diisopropyl naphthalene), carboxylic acids (2- (2,4-di -tert- amylphenoxy) butyric acid, and the like.
The following compounds are preferably used.

  Further, an organic solvent (such as ethyl acetate, butyl acetate, methyl ethyl ketone, cyclohexanone, or methyl cellosolve acetate) having a boiling point of 30 ° C. or higher and 160 ° C. or lower may be used in combination as an auxiliary solvent. The amount of the high-boiling organic solvent is 10 g or less, preferably 5 g or less, more preferably 1 g to 0.1 g based on 1 g of the hydrophobic additive used. In addition, 1 milliliter or less, further 0.5 milliliter or less, particularly 0.3 milliliter or less is appropriate for 1 g of binder.

A dispersion method using a polymer described in JP-B-51-39853 and JP-A-51-59943, or a fine particle dispersion described in JP-A-62-22422, etc. Can also be used. In the case of a compound that is substantially insoluble in water, it can be dispersed and contained as fine particles in a binder other than the above method.
In dispersing the hydrophobic compound in the hydrophilic colloid, various surfactants can be used. For example, the surfactants described in JP-A No. 59-157636, pages 37 to 38 can be used. Further, phosphate ester type surfactants described in JP-A-7-56267, JP-A-7-228589 and West German Patent No. 1,932,299A or the specification can also be used.

<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, preferably a weight average molecular weight of 10,000 or more, and more preferably a weight 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.

Moreover, it is more preferable that the polymer grafted with the ultraviolet absorber is made into a latex. The receptor layer can be formed by forming an aqueous dispersion type coating solution into a latex to form a latex, and the manufacturing cost can be reduced. For example, the method described in Japanese Patent No. 3450339 can be used as a method for forming a latex. Examples of the latex-made ultraviolet absorber include ULS-700, ULS-1700, ULS-1383MA, ULS-1635MH, XL-7016, ULS-933LP, ULS-935LH, Shin-Nakamura Chemical Co., Ltd. Commercially available ultraviolet absorbers such as New Coat UVA-1025W, New Coat UVA-204W, and New Coat UVA-4512M (both are trade names) can also be used.
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.

<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 mold release agent, silicone oil, phosphate ester plasticizer fluorine compound, and various wax dispersions can be used. In particular, silicone oil and wax dispersion are 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. A reaction product of vinyl-modified silicone oil and hydrogen-modified silicone oil is preferable. The addition amount of the release agent is preferably 0.2 to 30 parts by mass with respect to the receiving polymer.

A known dispersion can be used as the wax dispersion. In the present invention, “wax is treated as an organic substance having a solid or semi-solid alkyl chain at normal temperature” (according to the definition of “Revised properties and application of wax” (Shoshobo, 1989)). Examples of preferred compounds include candelilla wax, carnauba wax, rice wax, wood wax, montan wax, ozokerite, paraffin wax, microcrystalline wax, petrolactam, Fischer-Tropsch wax, polyethylene wax, montan wax derivatives, paraffin wax. Derivatives, microcrystalline wax derivatives, hardened castor oil, hardened castor oil derivatives, 12-hydroxystearic acid, stearamide, phthalic anhydride, chlorinated hydrocarbons, and other blended waxes. Of these, carnauba wax, montan wax and derivatives thereof, paraffin wax and derivatives thereof, microcrystalline wax and derivatives thereof, polyethylene wax and stearamide are preferred, kaunauba wax, mondan wax and derivatives thereof, and microcrystalline wax. Stearamide is more preferable, and montan wax and derivatives thereof, and microcrystalline wax are more preferable.
This wax is selected from those having a melting point of 25 ° C to 120 ° C, preferably 40 ° C to 100 ° C, more preferably 60 ° C to 90 ° C.
The wax is preferably an aqueous dispersion, and more preferably finely divided. The water dispersion method and the micronization method can be achieved by the methods described in “Revised Wax Properties and Applications” (Sachibo, 1989).
The addition amount of the wax is preferably 0.5% by mass to 30% by mass, more preferably 1% by mass to 20% by mass, and still more preferably 1.5% by mass to 15% by mass of the total solid content of the receiving layer. .

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), and more preferably 1 to 1. 8 g / m ^2, more preferably the coating weight of 2~7g / m ² is preferred. 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 or the like. 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 used in 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] a dispersion medium such as water enters a partition formed by polystyrene, acrylic resin, styrene-acrylic resin or the like. After coating and drying, non-foamed hollow particles in which the dispersion medium in 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 Foam that is covered with a resin made of polyacrylic acid, polyacrylic acid ester, or a mixture or polymer thereof, and the inside of which is hollowed by the expansion of the low-boiling liquid inside the particles by heating after coating. Type microballoons, and [3] microballoons obtained by heating and foaming the above [2] in advance to form a hollow polymer.

The particle size of these hollow polymers is preferably 0.1 to 20 μm, more preferably 0.1 to 2 μm, still more preferably 0.1 to 1 μm, and particularly preferably 0.2 to 0.8 μm. If the size is too small, the hollowness tends to decrease and the desired heat insulating property cannot be obtained.If the size is too large, the particle diameter of the hollow polymer is too large for the film thickness of the heat insulating layer to obtain a smooth surface. This is because it becomes difficult to cause coating failure due to coarse particles.
The hollow ratio of the hollow polymer is preferably about 20 to 70%, more preferably 20 to 50%. This is because when the hollow ratio is less than 20%, sufficient heat insulation cannot be obtained, and when the hollow ratio is excessively high, the ratio of incomplete hollow particles increases within a preferable particle size range, and sufficient film strength is obtained. This is because it cannot be obtained.
The hollow ratio of the hollow polymer in the present invention is a value P calculated by the following formula (a) in a transmission image taken from a transmission micrograph of the hollow particles.

  In the above formula (a), Rai represents the equivalent circle diameter of the inner contour (indicating the hollow portion contour) of the two contours constituting the image of the specific particle i, and Rbi represents the image of the specific particle i. Of the two contours to be constructed, the equivalent circular diameter of the outer contour (indicating the particle outer shape) is represented, n represents the number of measured particles, and n ≧ 300.

  The glass transition temperature (Tg) of the hollow polymer is preferably 70 ° C. or higher, and more preferably 100 ° C. or higher. Two or more types of hollow polymers can be mixed and used as necessary.

  Such hollow polymers are commercially available, and specific examples of the above [1] include Law and Haas Ropaque 1055, Dainippon Ink Boncoat PP-1000, JSR SX866 (B), Nippon Zeon Nippon MH5055 (both are trade names). 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., EXPANSELL 461DE, 551DE, and 551DE20 (all trade names) manufactured by Nippon Ferrite Co., Ltd. Among these, the hollow polymer of the series [1] can be used more preferably.

  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, and preferably between 5 and 1000 parts by mass when the solid content of the binder resin is 100 parts by mass. More preferably, it is more preferably between 5 and 400 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 is lowered, sufficient film strength cannot be obtained, and scratch resistance is obtained. Getting worse.

The image-receiving sheet used in the present invention does not contain a resin having no resistance to organic solvents in addition to the hollow polymer in the heat insulating layer. 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 (methyl ethyl ketone, ethyl acetate, benzene, toluene, xylene, etc.) is 1% by mass or less, preferably 0.5% by mass or less. Say. 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.

The porosity of the heat insulating layer calculated from the thickness of the heat insulating layer containing the hollow polymer and the solid coating amount of the heat insulating layer containing the hollow polymer is preferably 10 to 70%, and more preferably 15 to 60%. When the porosity of the heat insulating layer is less than 10%, sufficient heat insulating properties cannot be obtained, and when it is 70% or more, the binding force between the hollow polymers is lowered, and sufficient film strength cannot be obtained, and the scratch resistance is deteriorated.
In the present invention, the porosity of the heat insulating layer is a value V calculated by the following equation (b).

  In the above formula (b), L represents the film thickness of the heat insulating layer, gi represents the solid coating amount of the specific material i constituting the heat insulating layer, and di represents the specific gravity of the specific material i. Here, when di represents the specific gravity of the hollow polymer, di represents the specific gravity of the wall material of the hollow polymer.

(Underlayer)
An undercoat layer may be formed between the receiving layer and the heat insulating layer. For example, a white background adjusting layer, a charge adjusting layer, an adhesive layer, and a primer layer are formed. About these layers, it can be set as the structure similar to what was described, for example in patent 3585599, patent 2925244, etc.

(Support)
In the present invention, a water-resistant support is used as the support. By using a water-resistant support, it is possible to prevent moisture from being absorbed into the support, and to prevent a change in performance of the receiving layer over time. As the water-resistant support, for example, coated paper or 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 polyacrylate resin or polymethacrylate resin, polycarbonate resin, polyvinyl acetate resin, styrene acrylate resin, 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 resin, ethyl cellulose resin, cellulose acetate resin, etc., 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.

  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 extrudability. preferable.
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.

(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 formed by simultaneously applying at least one receiving layer, intermediate layer and 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, JP-A Nos. 2,761,791, 2,681,234, 3,508,947, 4,457,256, 3,993,019, Kaisho 63-54975, JP-A-61-278848, 55-86557, 52-31727, 55-142565, 50-43140, 63-80872, 54-54020 JP-A-5-104061, JP-A-5-127305, JP-B49-7050, or the specification of Edgar B. et al. The so-called slide coating method (slide coating method) and curtain coating method (curtain coating method) described in Guoff et al., “Coating and Drying Defects: Troubleshooting Operating Problems”, John Wiley & Sons, 1995, pages 101 to 103, etc. 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 weight 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 quickly solidify. 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 sheet (ink sheet) used in combination with the above-described thermal transfer image-receiving sheet of the present invention at the time of thermal transfer image formation is provided with a dye layer containing a diffusion transfer dye on a support. Ink sheets 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.

  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.

(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)

(Preparation of image-receiving sheet support)
50 parts by mass of LBKP (hardwood bleached kraft pulp) 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.
Subsequently, to the pulp slurry obtained above, cation-modified starch (manufactured by NSC Japan, trade name, CAT0304L) 1.3%, anionic polyacrylamide (manufactured by Seiko PMC Co., trade name) per pulp. DA4104) 0.15%, alkyl ketene dimer (Arakawa Chemical Co., Ltd., trade name, size pine K) 29%, epoxidized behenamide 0.29%, polyamide polyamine epichlorohydrin (Arakawa Chemical Co., Ltd., trade name, Arafix 100) 0.32% was added, followed by 0.12% defoamer .

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 for drying, the tensile force of the dryer canvas is 1.6 kg / After setting to cm and drying, a size press applies 1 g / m ² of polyvinyl alcohol (trade name, KL-118, manufactured by Kuraray Co., Ltd.) on both sides of the base paper and performs calendar treatment. It was. 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.

After performing corona discharge treatment on the wire surface (back surface) side of the obtained base paper, MFR (melt flow rate; hereinafter the same) 16.0 g / 10 min, density 0.96 g / cm using a melt extruder. ³ high density polyethylene (hydrotalcite (trade name: DHT-4A, manufactured by Kyowa Chemical Industry Co., Ltd.) 250 ppm, secondary antioxidant (tris (2,4-di-t-butylphenyl) phosphite, Trade name: Irgafos 168, manufactured by Ciba Specialty Chemicals Co., Ltd., containing 200 ppm), MFR 4.0 g / 10 min, low density polyethylene having a density of 0.93 g / cm ³ , 75/25 (mass ratio) ) Was coated so that the thickness was 21 g / m @ 2 to form a thermoplastic resin layer comprising a mat surface (hereinafter, this thermoplastic resin layer surface was referred to as "back surface"). This thermoplastic resin layer on the back side is further subjected to corona discharge treatment, and then, as an antistatic agent, aluminum oxide (trade name, alumina sol 100, manufactured by Nissan Chemical Industries, Ltd.) and silicon dioxide ( A dispersion obtained by dispersing Nissan Chemical Industries, Ltd. (trade name, Snowtex O) in water at a mass ratio of 1: 2 was applied so that the dry mass was 0.2 g / m ² . corona treated MFR 4.0 g / 10 min with 10 wt% of titanium oxide, by using a melt extruder so that the low-density polyethylene having a density of 0.93 g / m ² to 27 g / m ² was applied to the surface, A thermoplastic resin layer comprising a mirror surface was formed.

(Preparation of emulsified dispersion A)
Emulsified dispersion A was prepared by the following procedure. Antioxidant (EB-9) was dissolved in 42 g of a high boiling point solvent (Solv-5) and 20 ml of ethyl acetate, and this liquid was stirred and emulsified in 250 g of a 20% by weight gelatin aqueous solution containing 1 g of sodium dodecylbenzenesulfonate. (Dissolver) was emulsified and dispersed, and water was added to prepare 380 g of emulsified dispersion A.
The addition amount of the antioxidant (EB-9) was adjusted to 30 mmol in the emulsified dispersion A.

Example 1
(Preparation of polymer latex 1)
After sufficiently replacing the inside of the polymerization vessel equipped with a stirrer, a condenser, a thermometer and a nitrogen gas inlet with nitrogen, 1150 g of deionized water, 100 g of methyl acrylate, and 30 g of dodebesive benzene sulfonic acid soda were added, and the inside of the polymerization vessel was further charged. The pressure was reduced and 900 parts of vinyl chloride was charged. After raising the temperature in the polymerization vessel to 60 ° C., 50 parts of a 1% aqueous solution of ammonium persulfate was injected to start the reaction, and the reaction was continued for 16 hours while maintaining the internal temperature at 60 ° C. to complete the polymerization. Thereafter, the mixture was cooled to 30 ° C. and the pH was adjusted to 7-8 using 25% aqueous ammonia. After the preparation of polymer latex 1, the emulsion (polymer latex) was applied to a glass dry plate, and only the polymer component was extracted with chloroform. This extract was analyzed by H-NMR measurement, and the composition of the prepared emulsion-1 was determined to be vinyl chloride: methyl acrylate = 90: 10.

(Preparation of polymer latex 2-9)
Other than changing the amount of vinyl chloride used and the carbon number of the alcohol part of the acrylate ester (hereinafter, the alkyl part of the alcohol part is referred to as “alkyl group” and this carbon number is referred to as “alkyl carbon number”), In the same manner as the polymer latex 1, polymer latexes 2 to 9 shown in Table 1 below were prepared.

(Preparation of thermal transfer image receiving sheet 101 (present invention))
On the support prepared as described above, a multilayer composition coating composition comprising an undercoat layer, a heat-insulating layer, and a receiving layer was applied simultaneously from the lower layer. The composition and coating amount of the coating solution are shown below.

Undercoat layer coating liquid (composition)
93 parts by mass of styrene-butadiene latex (manufactured by Nippon A & L Co., Ltd., trade name, SR103)
Polyvinyl alcohol (PVA) 8.7% aqueous solution 57 parts by mass Adjust pH to 8 with NaOH (application amount) 21 ml / m ²

Heat insulation layer coating liquid (composition)
Hollow polymer latex 38 parts by mass (manufactured by Nippon Zeon Co., Ltd., trade name, MH5055)
16% aqueous gelatin solution 26 parts by weight Water 4 parts by weight Adjust pH to 8 with NaOH (coating amount) 45 ml / m ²

Receiving layer coating liquid (composition)
Prepared polymer latex 1 (solid content 40%) 50 parts by weight 10% gelatin aqueous solution 10 parts by weight Emulsified dispersion A prepared previously 13 parts by weight Microcrystalline wax 7 parts by weight (manufactured by Nippon Wax Co., Ltd., trade name, EMUSTAR-42X)
Water 35 parts by weight Adjust pH to 8 with NaOH (application amount) 18 ml / m ²

  The following compound X (crosslinking agent) was added to the receiving layer coating solution immediately before coating. The amount of compound X added was 3% by mass with respect to the total mass of gelatin in the heat insulating layer and the receiving layer.

(Preparation of thermal transfer image receiving sheets 102-109)
Thermal transfer image receiving sheets 102 to 109 were prepared in the same manner except that the prepared polymer latexes 2 to 9 were used in place of the polymer latex 1 used for the image receiving layer in the thermal transfer image receiving sheet 101. The amount of polymer latex was added so that the solid content was equal.

(Preparation of thermal transfer image-receiving sheet 110 (comparative example))
In the heat-sensitive transfer image-receiving sheet 101, the same procedure except that a commercially available latex polymer (water-dispersible polyester; MD-1200, trade name, manufactured by Toyobo Co., Ltd.) was used instead of the polymer latex 1 used for the image-receiving layer. Thus, a thermal transfer image receiving sheet 110 was produced.

(Image formation)
The ink sheet and the thermal transfer image-receiving sheets 101 to 110 were processed so as to be loaded, and output in a high-speed print mode using a sublimation thermal transfer printer ASK2000 (trade name, manufactured by Fuji Photo Film Co., Ltd.). As an output image, a full-scale black image (black solid image) with the highest density was used, and 20 sheets were continuously output. At this time, the time from the discharge of the first sheet to the discharge of the second sheet was 8 seconds.

(Image evaluation)
(1) Dmax evaluation The visual density of a black image obtained under the above conditions was measured with a Photographic Densitometer (trade name, manufactured by X-Rite Incorporated).
(2) Evaluation of releasability (adhesiveness) The releasability between the ink sheet and the image receiving sheet is as follows. The full density black image (black solid image) is output, the surface is observed, and streaky unevenness (sticking) ) Was evaluated. In addition, we listened to the processing sound generated during this process and evaluated its magnitude. These results are shown in Table 2 below in the following evaluation rank.

Evaluation rank A: Better results were obtained than the level B.
A: Good results were obtained without any problem.
(Triangle | delta): Although it is a tendency to deteriorate, it is an acceptable level.
X: A problem and an unacceptable level.

From sample 101 to sample 110 (sample 101 to sample 107 vs sample 108 to 110), the vinyl chloride / acrylic acid ester containing 50% by mass or more of vinyl chloride according to the present invention has performance (transfer density, sticking, ink sheet). It was found that the peeling sound of
Moreover, from the samples 101 to 107, when the vinyl chloride / acrylate ratio is 9/1, the performance (transfer density, sticking, peeling sound of the ink sheet) varies depending on the number of carbon atoms of the alkyl group of the acrylate, and the alkyl group of the acrylate It has been found that particularly excellent performance is exhibited when the number of carbon atoms is 1 or more and 8 or less. When the vinyl chloride / acrylate ratio is 9/1, the preferred alkyl group component of the acrylate is methyl, propyl, 2-ethylhexyl, hexyl, more preferably methyl, propyl, 2-ethylhexyl, most preferably ethyl, butyl. Met.

Example 2
(Preparation of polymer latex 11-16)
Polymer latexes 11 to 16 shown in Table 3 below were prepared in the same manner as in polymer latex 1 except that the amount of vinyl chloride used and the number of alkyl carbon atoms in the acrylate ester and the amount thereof were changed.

(Preparation of thermal transfer image receiving sheets 111-116)
Thermal transfer image receiving sheets 111 to 116 were prepared in the same manner except that the synthesized polymer latexes 11 to 16 were used instead of the polymer latex 1 used for the image receiving layer in the thermal transfer image receiving sheet 101. The amount of polymer latex was added so that the solid content was equal.

  The obtained heat-sensitive transfer image-receiving sheets 111 to 116 were tested in the same manner as in Example 1. The results are shown in Table 4 below.

  From Samples 111 to 116, when the carbon number of the alkyl group of the acrylate ester is 1, Samples 112 to 114 in which the ratio of vinyl chloride / acrylate ester is in the range of 10/90 to 45/55 are even better. It turned out to be performance. Among them, in the case of methyl acrylate, vinyl chloride / methyl acrylate ratio = 75/25 vicinity was the most excellent performance.

Example 3
(Preparation of polymer latex 21-26)
Polymer latexes 21 to 26 shown in Table 5 were prepared in the same manner as in polymer latex 1 except that the amount of vinyl chloride used and the number of alkyl carbon atoms and the amount of acrylic ester used were changed.

(Preparation of thermal transfer image receiving sheets 121-126)
Thermal transfer image receiving sheets 101 to 126 were prepared in the same manner as in the thermal transfer image receiving sheet 101 except that the synthesized polymer latexes 21 to 26 were used instead of the polymer latex 1 used for the image receiving layer. The amount of polymer latex was added so that the solid content was equal.

  The obtained heat-sensitive transfer image-receiving sheets 121 to 126 were tested in the same manner as in Example 1. The results are shown in Table 6 below.

  From Samples 121 to 126, when the carbon number of the alkyl group of the acrylate ester is 2, Samples 121 to 124 in which the ratio of vinyl chloride / acrylate ester is in the range of 5/95 to 40/60 are even better. It turned out to be performance. In particular, in the case of ethyl acrylate, vinyl chloride / methyl acrylate ratio = 80/20 was the most excellent performance.

Example 4
(Preparation of polymer latex 31-36)
Polymer latexes 31 to 36 shown in Table 7 were prepared in the same manner as polymer latex 1 except that the amount of vinyl chloride used and the number of alkyl carbon atoms and the amount of acrylic ester used were changed.

(Preparation of thermal transfer image receiving sheets 131-136)
In the heat-sensitive transfer image-receiving sheet 101, heat-sensitive transfer image-receiving sheets 131 to 136 were produced in the same manner except that the synthesized polymer latexes 31 to 36 were used instead of the polymer latex 1 used for the image-receiving layer. The amount of polymer latex was added so that the solid content was equal.

  The obtained heat-sensitive transfer image-receiving sheets 131 to 136 were tested in the same manner as in Example 1. The results are shown in Table 8 below.

  From Samples 131 to 136, when the carbon number of the alkyl group of the acrylate ester is 4, Samples 131 to 134 in which the ratio of vinyl chloride / acrylate ester is in the range of 5/95 to 30/70 are even better. It turned out to be performance. In particular, in the case of butyl acrylate, the vinyl chloride / methyl acrylate ratio = near 90/10 was the most excellent performance.

Example 5
(Preparation of polymer latex 41-45)
Polymer latexes 41 to 45 shown in Table 9 were prepared in the same manner as in polymer latex 1 except that the amount of vinyl chloride used and the number of alkyl carbons in the acrylate ester and the amount used were changed.

(Preparation of thermal transfer image-receiving sheets 141-145)
Thermal transfer image receiving sheets 141 to 145 were prepared in the same manner as in the thermal transfer image receiving sheet 101 except that the synthesized polymer latexes 41 to 45 were used instead of the polymer latex 1 used for the image receiving layer. The amount of polymer latex was added so that the solid content was equal.

  The obtained heat-sensitive transfer image-receiving sheets 141 to 145 were tested in the same manner as in Example 1. The results are shown in Table 10 below.

  From Samples 141 to 145, when the alkyl group of the acrylate ester has 8 carbon atoms, Samples 141 to 144 having a vinyl chloride / acrylate ratio in the range of 2/98 to 25/75 are even better. It turned out to be performance. Among them, in the case of 2-ethylhexyl acrylate, the vinyl chloride / methyl acrylate ratio = near 90/10 was the most excellent performance.

Example 6
(Preparation of polymer latex 51-58)
Polymer latexes 51 to 58 shown in Table 11 were prepared in the same manner as in polymer latex 1 except that the amount of vinyl chloride used and the number of alkyl carbons in the acrylate ester and the amount used were changed.

(Preparation of thermal transfer image receiving sheets 151 to 158)
Thermal transfer image receiving sheets 151 to 158 were prepared in the same manner except that the synthesized polymer latexes 51 to 58 were used instead of the polymer latex 1 used for the image receiving layer in the thermal transfer image receiving sheet 101. The amount of polymer latex was added so that the solid content was equal.

  The obtained heat-sensitive transfer image-receiving sheets 151 to 158 were tested in the same manner as in Example 1. The results are shown in Table 12 below.

From Sample 151 to Sample 158, when the number of carbon atoms of the alkyl group of the acrylate ester is 6 or 8, the samples 151, 152, 155, and 156 satisfying the vinyl chloride / acrylate ratio of the present invention are transferred density and sticking. It was found that all the performance of the ink sheet peeling sound was achieved.
From Sample 151 to Sample 154, when the carbon number of the alkyl group of the acrylate ester is 3, Samples 151 and 152 in which the ratio of vinyl chloride / acrylate ester is in the range of 5/95 to 35/65 are even better performance I found out.
From Samples 155 to 158, when the number of carbon atoms of the alkyl group of the acrylate ester is 6, Samples 155 and 156 in which the ratio of vinyl chloride / acrylate ester is in the range of 3/97 to 28/72 have better performance. I found out.

Example 7
(Preparation of polymer latex 61-66)
Polymer latexes 61 to 66 shown in Table 13 were prepared in the same manner as polymer latex 1 except that the amount of vinyl chloride used and the amount of vinyl acetate used instead of the acrylic ester were changed.

(Preparation of thermal transfer image-receiving sheets 161-168)
Thermal transfer image receiving sheets 161 to 168 were prepared in the same manner except that the synthesized polymer latexes 61 to 68 were used instead of the polymer latex 1 used for the image receiving layer in the thermal transfer image receiving sheet 101. The amount of polymer latex was added so that the solid content was equal.

  The obtained heat-sensitive transfer image-receiving sheets 161 to 168 were tested in the same manner as in Example 1. The results are shown in Table 14 below.

  From Sample 161 to Sample 168, Samples 161 to 163 in which the latex has a vinyl chloride / vinyl acetate ratio of the present invention, Samples 164 and 165 made of a ternary polymer of vinyl chloride / acrylate / acrylate, and vinyl chloride / acrylate / acetic acid Samples 166 and 167 made of vinyl ternary polymer were found to have excellent performance.

  Images similar to those in Examples 1 to 7 except that the thermal transfer image-receiving sheet prepared in Examples 1 to 7 was changed to a sublimation type thermal transfer printer CW01 (trade name, manufactured by Citizen Co., Ltd.). As a result of the formation, the heat-sensitive transfer image-receiving sheet of the present invention obtained good results in the same manner.

Example 8
In the production of the polymer latex 1 of Example 1, polymer latexes A to D were produced in the same manner except that the acrylic acid ester copolymerized with the vinyl chloride monomer was changed to the composition shown in Table 15 below. Polymer latexes A to D are samples in which different acrylic esters are copolymerized with vinyl chloride and the glass transition temperature of the constituent polymer is adjusted to around 65 ° C. by changing the copolymerization ratio.
Next, samples 801 to 805 were prepared in the same manner except that the polymer latex 1 was changed to the polymer latexes A to E in the preparation of the sample 101.
In addition, Sample 806 was prepared in the same manner as Sample 802 except that the receiving layer gelatin was not added.
Further, a sample 807 was prepared in the same manner except that the heat insulating layer was not applied from the sample 802. In the application of the sample 802, the undercoat layer and the heat insulating layer were applied in layers and dried, and then the receiving layer was applied sequentially. Sample 808 was prepared in the same manner as described above.
Sample 809 was prepared in the same manner except that no gelatin was added to the heat insulating layer of sample 802.

(Image formation)
The ink sheet and the thermal transfer image-receiving sheet samples 801 to 809 were processed so that they could be loaded and output in a high-speed print mode using a sublimation thermal transfer printer ASK2000 (trade name, manufactured by Fuji Photo Film Co., Ltd.). . As the output image, five gray solid images of each sample were continuously output by a signal in which neutral gray was adjusted so that the visual density of the sample 801 was 1.0. The time from the discharge of the first sheet to the discharge of the second sheet was 8 seconds.
The evaluation of transferability near the maximum density has a relatively large contribution to the saturation adsorption amount of the dye and the thermal stability of the receiving polymer, and corresponds to the evaluation of the overall transfer performance of the receiving polymer. At 1.0, the influence of the transfer effect of the receiving polymer tends to be relatively large.

(Image evaluation)
(1) Evaluation of color density The visual density of a black image obtained under the above conditions was measured with a Photographic Densitometer (trade name, manufactured by X-Rite Incorporated). Furthermore, the surface quality of the gray solid image was observed, and the uniformity of the solid image and the occurrence state of the image failure were evaluated.
(2) Evaluation of releasability (adhesiveness) In an environment of 35 ° C and 80%, the releasability of the ink sheet and the image receiving sheet is the continuous output of 50 full-color black images (solid black images) at the highest density. The surface was observed, stripe-like unevenness (sticking) was evaluated, and the level at which transfer deviation occurred was regarded as a problem level, and the number of occurrences of this was taken as the occurrence frequency of sticking. In addition, we listened to the processing sound generated during this process and evaluated its magnitude. These results are shown in the following Table 15 with the following evaluation ranks (note that this evaluation environment is an environment in which sticking easily occurs).

Evaluation rank (processed sound)
A: Better results were obtained than the level B.
A: Good results were obtained without any problem.
(Triangle | delta): Although it is a tendency to deteriorate, it is an acceptable level.
X: A problem and an unacceptable level.

  Using these samples 801 to 809, images were output in the same manner as in Example 1, and the same evaluation was performed. Furthermore, a gray solid image having a gray density of 0.6 was output, and images of samples 801 to 809 were observed. The results are shown in Table 16 below.

From the results shown in Table 16, compared to the samples 807 to 809 of the comparative example, the samples 801 to 806 that satisfy the requirements of the present invention have high image quality in which transferability and peelability (sticking) from the ink ribbon are compatible. I found out that Further, among samples satisfying the requirements of the present invention, sample 802 using a polymer latex obtained by copolymerizing ethyl acrylate and vinyl chloride has a similar glass transition temperature (Tg) to other acrylic esters. It was found that a good image quality in which both transferability and adhesion to the ink ribbon were compatible with each other as compared with the copolymer was obtained. Furthermore, the sample 804 using a polymer latex obtained by copolymerizing butyl acrylate and vinyl chloride is superior in transferability specifically compared to a copolymer with other acrylic ester having the same Tg. all right.

Claims (14)

  The support has at least one receiving layer containing a polymer latex containing a repeating unit obtained from vinyl chloride in an amount of 50% by mass or more, and at least one hollow layer is provided between the receiving layer and the support. A heat-sensitive transfer image-receiving sheet comprising: a polymer latex; and a heat insulating layer containing a water-soluble polymer.   The thermal transfer image-receiving sheet according to claim 1, wherein the polymer latex of the receiving layer is a copolymer with acrylates.   The heat-sensitive transfer image-receiving sheet according to claim 2, wherein the polymer latex of the receiving layer is a copolymer with at least two kinds of acrylic acid esters.   The heat-sensitive transfer image-receiving sheet according to claim 2 or 3, wherein the alcohol portion of the acrylate ester has 1 to 8 carbon atoms.   The number of carbon atoms in the alcohol part of the acrylic ester is 1 and 10 to 45% by mass of a repeating unit obtained from the acrylic ester is contained in the copolymer. The heat-sensitive transfer image-receiving sheet according to any one of the above.   The number of carbon atoms in the alcohol part of the acrylate ester is 2, and the copolymer contains 5 to 45% by mass of a repeating unit obtained from the acrylate ester. The heat-sensitive transfer image-receiving sheet according to any one of the above.   The number of carbon atoms in the alcohol part of the acrylate ester is 3, and the copolymer contains 5 to 35% by mass of a repeating unit obtained from the acrylate ester. The heat-sensitive transfer image-receiving sheet according to any one of the above.   The number of carbon atoms in the alcohol part of the acrylate ester is 4, and 4 to 30% by mass of a repeating unit obtained from the acrylate ester is contained in the copolymer. The heat-sensitive transfer image-receiving sheet according to any one of the above.   The number of carbon atoms in the alcohol part of the acrylate ester is 6, and the copolymer contains 3 to 28% by mass of a repeating unit obtained from the acrylate ester. The heat-sensitive transfer image-receiving sheet according to any one of the above.   The number of carbon atoms in the alcohol part of the acrylate ester is 8, and 2 to 25% by mass of a repeating unit obtained from the acrylate ester is contained in the copolymer. The heat-sensitive transfer image-receiving sheet according to any one of the above.   The thermal transfer image-receiving sheet according to any one of claims 1 to 10, wherein the polymer latex of the receptor layer is a copolymer with vinyl acetate.   The thermal transfer image-receiving sheet according to claim 11, wherein the copolymer contains 3 to 30% by mass of a repeating unit obtained from vinyl acetate.   2. The thermal transfer image-receiving sheet according to claim 1, wherein the polymer latex of the receiving layer is a copolymer of vinyl chloride, at least one of acrylates and vinyl chloride.   The heat-sensitive transfer image-receiving sheet according to claim 1, wherein the heat-sensitive transfer image-receiving sheet is produced by simultaneously applying the receptor layer and the heat-insulating layer in the production process.