JP5108620B2 - Composition for dye-receiving layer - Google Patents

Description

  The present invention relates to a dye receiving layer composition and a dye thermal transfer image receiving sheet using the same.

There has been proposed a method of forming a color image on a thermal transfer image-receiving sheet that can be dyed with a sublimation dye, using a sublimation dye as a recording agent and a thermal transfer sheet carried on a substrate. In this method, a thermal head of a printer is used as a heating means, and a dye is transferred to an image receiving sheet by heating to obtain a color image. The image formed in this way is very clear because it uses a dye, and is excellent in transparency. Therefore, it is excellent in reproducibility of intermediate colors and gradation, and a high-quality image can be expected.
In the production of the thermal transfer image-receiving sheet, a film-forming aid is usually used to enhance the film-forming property when a dye-receiving layer that receives a sublimable dye is applied to a substrate.
As a thermal transfer image-receiving sheet using a film-forming aid, for example, on a support, it has a receiving layer containing a polymer latex formed by aqueous coating and a heat insulating layer containing a hollow polymer, and a constituent layer on the receiving layer side Has disclosed a heat-sensitive transfer image-receiving sheet obtained by applying a coating liquid having a boiling point of 140 ° C. or higher and 220 ° C. or lower and containing 3% or less of an organic solvent with respect to the total solid content (Patent Documents). 1).

JP 2007-190910 A

However, when a thermal transfer image-receiving sheet is produced using a film-forming aid having a high film-forming property, drying at a low temperature requires a long time, which is not sufficient in terms of productivity. Further, the obtained image-receiving sheet may be difficult to peel off due to thermal fusion with a thermal transfer sheet carrying a sublimable dye during image formation (thermal fusion property). It was not enough.
The present invention provides a thermal transfer image-receiving sheet that can be dried at a low temperature and in a short time and has excellent heat-fusibility, and a composition for a dye-receiving layer used therefor, and has excellent print sensitivity and high density. It is an object of the present invention to provide a thermal transfer image-receiving sheet having excellent image performance and a composition for a dye-receiving layer used therefor.

The present invention
(1) (a) Resin dispersion of resin containing polyester, (b) Glycol ethers having a boiling point of 160 to 280 ° C. and a vapor pressure at 20 ° C. of 20 Pa or more, and (c) oxazoline group A composition for a dye-receiving layer for a thermal transfer image-receiving sheet, comprising a compound having
(2) (I) a step of obtaining a resin dispersion of a resin containing polyester in an aqueous medium, and (II) (a) the resin dispersion obtained in step (I), (b) at 160 to 280 ° C. A step of mixing a glycol ether having a boiling point and a vapor pressure at 20 ° C. of 20 Pa or more, and (c) a compound having an oxazoline group,
A method for producing a dye-receiving layer composition for a thermal transfer image-receiving sheet,

(3) A thermal transfer image-receiving sheet having a dye-receiving layer containing the dye-receiving layer composition described in (1) above on a substrate, and (4) (I) a resin resin containing polyester in an aqueous medium Obtaining a dispersion;
(II) (a) the resin dispersion obtained in step (I), (b) glycol ethers having a boiling point of 160 to 280 ° C. and a vapor pressure at 20 ° C. of 20 Pa or more, and (c) ) A step of mixing a compound having an oxazoline group to obtain a composition for a dye receiving layer; and
(III) a step of providing a dye-receiving layer containing the dye-receiving layer composition obtained in step (II) on the substrate;
A method for producing a thermal transfer image-receiving sheet,
About.

  According to the present invention, it is possible to provide a thermal transfer image-receiving sheet that can be dried at a low temperature and in a short time, and excellent in heat-fusibility, and a composition for a dye-receiving layer used therefor, and excellent in print sensitivity, It is possible to provide a thermal transfer image-receiving sheet having excellent image performance, such as being able to obtain a high-density image, and a dye-receiving layer composition used therefor.

[Composition for dye receiving layer]
The composition for a dye-receiving layer for a thermal transfer image-receiving sheet of the present invention comprises (a) a resin dispersion of a resin containing polyester, (b) a boiling point of 160 to 280 ° C., and a vapor pressure at 20 ° C. of 20 Pa. The glycol ethers as described above and (c) a compound having an oxazoline group are contained. The dye-receiving layer can be formed by applying the composition for dye-receiving layer to a coating liquid and drying the composition on a substrate.

((A) Resin dispersion of resin containing polyester)
In the present invention, the resin dispersion is obtained by a method of emulsifying a resin containing polyester, or obtained by a method of emulsifying and dispersing a polycondensable monomer in an aqueous medium by, for example, mechanical shearing or ultrasonic waves. Among them, from the viewpoint of obtaining resin particles having a small particle diameter, those obtained by emulsifying a resin containing polyester are preferable.
There is no restriction | limiting in particular as resin polyester containing polyester, It obtains by polycondensing a well-known alcohol component and a well-known carboxylic acid component as a raw material component.
Examples of the alcohol component that is a raw material monomer for forming the polyester include ethylene glycol, propylene glycol, alkylene oxide adduct of 2,2-bis (4-hydroxyphenyl) propane, glycerin, pentaerythritol, trimethylolpropane, hydrogen Addition bisphenol A, sorbitol, those alkylene (2-4 carbon atoms) oxide (average addition mole number 1-16) adduct, etc. are mentioned. This alcohol component may be used individually by 1 type, and may be used in combination of 2 or more type.

In the present invention, as an alcohol component which is a raw material component of the polyester, from the viewpoint of heat-fusibility (also referred to as releasability) of the thermal transfer image-receiving sheet and dyeing property, the formula (1)

(In the formula, RO is an oxyalkylene group, R is an ethylene group and / or propylene group, x and y represent the number of added moles of alkylene oxide, each is a positive number, and the sum of x and y) Is an average value of 2 to 7.)
It is preferable to use an alkylene oxide adduct of 2,2-bis (4-hydroxyphenyl) propane represented by: From the above viewpoint, the alkylene oxide adduct of 2,2-bis (4-hydroxyphenyl) propane represented by the above formula (1) is preferably contained in the raw alcohol component in an amount of 50 mol% or more, more preferably. Is contained in an amount of 70 mol% or more, more preferably 80 mol% or more, and still more preferably 100 mol%.

In the general formula (1), RO represents an oxyalkylene group, and R represents an ethylene group and / or a propylene group. x and y represent the number of moles of alkylene oxide added and each is a positive number. Each R may be the same or different, but from the viewpoint of reactivity with the carboxylic acid component, the average value of the sum of x and y is 2 to 7, preferably 2 to 5.
As the alkylene oxide adduct of 2,2-bis (4-hydroxyphenyl) propane represented by the above formula (1), specifically, polyoxypropylene-2,2-bis ( 4-hydroxyphenyl) propane, polyoxyethylene-2,2-bis (4-hydroxyphenyl) propane and the like.
In the present invention, from the viewpoint of releasability of the thermal transfer image-receiving sheet, it is preferable to use a trivalent or higher alcohol as the alcohol component, and specifically, it is more preferable to use glycerin or pentaerythritol.

Specific examples of the carboxylic acid component as a raw material component include dicarboxylic acids such as phthalic acid, isophthalic acid, terephthalic acid, fumaric acid, maleic acid, adipic acid, and succinic acid, and carbons such as dodecenyl succinic acid and octenyl succinic acid. Succinic acid substituted with an alkyl group having 1 to 20 carbon atoms or an alkenyl group having 2 to 20 carbon atoms; a trivalent or higher polyvalent carboxylic acid such as trimellitic acid and pyromellitic acid, anhydrides of those acids, and their Alkyl (C1-C3) ester etc. are mentioned. The carboxylic acid component preferably contains an aromatic dicarboxylic acid from the viewpoint of releasability of the thermal transfer image-receiving sheet and dyeability, and specifically, phthalic acid, isophthalic acid, terephthalic acid and the like are preferable. . The aromatic dicarboxylic acid is preferably contained in an amount of 50 mol% or more, more preferably 60 mol% or more in the total carboxylic acid. The said carboxylic acid component may be used individually by 1 type, and may be used in combination of 2 or more type.
In the present invention, from the viewpoint of releasability of the thermal transfer image-receiving sheet, it is preferable to use a trivalent or higher carboxylic acid as the carboxylic acid component. Specifically, trimellitic acid or pyromellitic acid is used. More preferred is trimellitic acid.

In the present invention, succinic acid having an alkyl group and / or alkenyl group is preferably used from the viewpoint of dyeing property of the dye onto the thermal transfer image-receiving sheet, and alkyl having 1 to 22 carbon atoms such as dodecenyl succinic acid and octenyl succinic acid. It is more preferable to use a succinic acid substituted with a group or an alkenyl group having 2 to 22 carbon atoms, and a linear, branched or cyclic group having 8 to 22 carbon atoms, more preferably 10 to 20 carbon atoms. Or a linear, branched or cyclic alkenyl group having 8 to 22 carbon atoms, more preferably 10 to 20 carbon atoms, is more preferable.
Specifically, in the succinic acid having an alkyl group and / or an alkenyl group, examples of the alkyl group include various octyl groups, various decyl groups, various dodecyl groups, various tetradecyl groups, various hexadecyl groups, various octadecyl groups, various icosyl groups. Examples include groups.

Examples of the alkenyl group include various octenyl groups, various decenyl groups, various dodecenyl groups, various tetradecenyl groups, various hexadecenyl groups, various octadecenyl groups, and various icocenyl groups.
The succinic acid having an alkyl group and / or an alkenyl group is preferably contained in the carboxylic acid component in an amount of 5 to 50 mol%, thereby improving the dyeing property of the dye on the thermal transfer image-receiving sheet. This is presumably because the interaction between the polyesters is weakened due to the presence of the alkyl group and / or alkenyl group in the side chain of the succinic acid, and the dye penetrates into the inside of the polyester. From the viewpoint of dyeability of the dye on the image receiving sheet, the succinic acid is more preferably contained in the carboxylic acid component in an amount of 10 to 40 mol%, and further preferably 20 to 40 mol%.

  The polyester can be produced, for example, by subjecting the alcohol component and the carboxylic acid component to condensation polymerization at a temperature of 180 to 250 ° C. in an inert gas atmosphere, using an esterification catalyst as necessary. From the viewpoint of releasability and dyeability of the thermal transfer image-receiving sheet of the present invention, the raw material polyester preferably has a broad molecular weight distribution, and may be subjected to condensation polymerization using an esterification catalyst. preferable. Examples of the esterification catalyst include metal compounds such as tin catalyst, titanium catalyst, antimony trioxide, zinc acetate, and germanium oxide.

From the viewpoint of releasability of the thermal transfer image-receiving sheet and dyeing property, the softening point of the polyester is preferably 80 to 250 ° C, more preferably 120 to 250 ° C. The glass transition point is preferably 50 to 85 ° C. The acid value is preferably from 1 to 35 mgKOH / g, more preferably from 5 to 35 mgKOH / g, from the viewpoint of dispersibility of the resin containing polyester in an aqueous medium, that is, emulsifying properties. The glass transition point, softening point, and acid value can all be obtained by appropriately adjusting the type of monomer used, the blending ratio, the temperature of condensation polymerization, and the reaction time.
In addition, from the viewpoint of film forming properties when obtaining a thermal transfer image-receiving sheet, the number average molecular weight of the polyester is preferably 1,000 to 10,000, and more preferably 2,000 to 8,000.

  In the present invention, the polyester includes a polyester modified within such a range that does not substantially impair the characteristics. Examples of the modified polyester include grafting and blocking with phenol, urethane, epoxy and the like by the methods described in JP-A-11-133668, JP-A-10-239903, JP-A-8-20636, and the like. And a composite resin having two or more kinds of resin units including a polyester unit.

  In the present invention, the resin that can be used together with the polyester in the resin containing polyester includes known resins used as the receiving layer of the thermal transfer image-receiving sheet, for example, polyolefin resins such as polypropylene, polyvinyl chloride, and polyvinylidene chloride. Vinyl polymers such as halogenated polymers, polyvinyl acetate, polyacrylic esters, polyvinyl acetals, polystyrene resins, polyamide resins, copolymers of olefins such as ethylene and propylene with other vinyl monomers, ionomers, cellulose diacetate And the like, and from the viewpoints of releasability of the thermal transfer image-receiving sheet and dyeability, polyvinyl chloride and polycarbonate are preferred.

  In the present invention, the resin containing polyester is preferably contained in the resin dispersion together with the release agent as the resin particles in the resin dispersion dispersed in the aqueous medium from the viewpoint of environmental properties. . The content of the polyester in the resin containing polyester is preferably 70% by weight or more, more preferably 80% by weight or more, and still more preferably 100% by weight from the viewpoint of dyeing properties of the dye on the thermal transfer image-receiving sheet. .

Resin dispersion The aqueous medium in which the resin containing the polyester is dispersed is mainly composed of water, that is, water is 50% by weight or more. From the environmental viewpoint, the content of water in the aqueous medium is preferably 80% by weight or more, more preferably 90% by weight or more, and further preferably 100% by weight. Examples of components other than water include organic solvents that dissolve in water, such as methanol, ethanol, isopropanol, butanol, acetone, methyl ethyl ketone, and tetrahydrofuran.

The resin particles in the resin dispersion in which a resin containing polyester is dispersed preferably have a volume median particle size (D50) of 1 μm or less from the viewpoint of film forming properties when obtaining a thermal transfer image-receiving sheet. It is more preferable that it is 1 micrometer, More preferably, it is 50-800 nm. Here, “volume median particle size (D50)” means a particle size at which the cumulative volume frequency calculated by the volume fraction is 50% when calculated from the smaller particle size. The measuring method is as described later.
The resin containing polyester is preferably contained in the solid content of the resin dispersion from 80 to 100% by weight, more preferably from 85 to 100% by weight, from the viewpoint of dyeability of the dye on the thermal transfer image-receiving sheet. Contained, more preferably 90 to 100% by weight.

The resin dispersion is obtained by dissolving a resin containing the polyester in a ketone solvent, adding a neutralizing agent to ionize the carboxyl group of the resin containing the polyester, then adding water, and then distilling off the ketone solvent. And can be obtained by a method of phase inversion to an aqueous system. Specifically, for example, a reactor equipped with a stirrer, a reflux condenser, a thermometer, a dropping funnel, and a nitrogen gas introduction pipe is prepared, and a neutralizer is added to a resin containing polyester dissolved in a ketone solvent. Then, the carboxyl group is ionized (unnecessary if already ionized), and then water is added, and then the ketone solvent is distilled off and the phase is changed to an aqueous system. The dissolution in the ketone solvent and the addition of the neutralizing agent are usually carried out at a temperature not higher than the boiling point of the ketone solvent, and examples of the water used here include deionized water.
Examples of the ketone solvent used here include acetone, methyl ethyl ketone, diethyl ketone, dipropyl ketone, methyl isobutyl ketone, and methyl isopropyl ketone. From the viewpoint of the solubility of the resin and the ease of evaporation of the solvent. Preferably, methyl ethyl ketone is used.

  Examples of the neutralizing agent include aqueous alkaline solutions such as aqueous ammonia and sodium hydroxide, allylamine, isopropylamine, diisopropylamine, ethylamine, diethylamine, triethylamine, 2-ethylhexylamine, 3-ethoxypropylamine, diisobutylamine, and 3-diethylamino. Propylamine, tri-n-octylamine, t-butylamine, sec-butylamine, propylamine, methylaminopropylamine, dimethylaminopropylamine, n-propanolamine, butanolamine, 2-amino-4-pentanol, 2- Amino-3-hexanol, 5-amino-4-octanol, 3-amino-3-methyl-2-butanol, monoethanolamine, N, N-dimethylethanolamine, isopropanol Amine, neopentanolamine, diglycolamine, ethylenediamine, 1,3-diaminopropane, 1,2-diaminopropane, 1,6-diaminohexane, 1,9-diaminononane, 1,12-diaminododecane, dimer Fatty acid diamine, 2,2,4, -trimethylhexamethylenediamine, 2,4,4, -trimethylhexamethylenediamine, hexamethylenediamine, N-aminoethylpiperazine, N-aminopropylpiperazine, N-aminopropyldipiperidi Examples thereof include amines such as propane and piperazine, and ammonia is preferred from the viewpoint of emulsifiability and volatility of the resin. These neutralizing agents may be used in an amount that can neutralize at least the acid value of the resin containing polyester.

From the viewpoint of storage stability, storage stability of the thermal transfer image-receiving sheet obtained using the resin dispersion, and releasability, the resin dispersion has a glass transition point of 40 to 80 ° C. It is preferable that there is, more preferably 50 to 75 ° C. Moreover, it is preferable that a softening point is 80-250 degreeC, More preferably, it is 100-220 degreeC. The number average molecular weight is the same as the molecular weight of the polyester.
From the viewpoint of productivity, the solid content concentration in the resin dispersion is preferably 20 to 45% by weight, more preferably 25 to 40% by weight, and further preferably 30 to 40% by weight. Further, the pH of the resin dispersion at 25 ° C. is preferably 5 to 10, more preferably 6 to 9, and further preferably 7 to 9 from the viewpoint of the storage stability of the resin dispersion.

((B) Glycol ethers)
The dye-receiving layer composition of the present invention contains glycol ethers having a boiling point of 160 to 280 ° C. and a vapor pressure at 20 ° C. of 20 Pa or more. In the present invention, by using a film-forming aid having a boiling point and a vapor pressure within an appropriate range, it is possible to obtain a composition for a receiving layer that has excellent film-forming properties and can be dried at a low temperature in a short time. As a result, it is possible to obtain a thermal transfer image-receiving sheet that is excellent in heat-fusibility, excellent in printing sensitivity, and capable of obtaining a high-density image. This is because the glycol ethers of the present invention have a high boiling point and excellent film-forming properties of the thermal transfer image-receiving sheet, and are highly volatile and volatilize during the drying process, so that the resulting thermal transfer image-receiving sheet has almost no glycol ethers. For this reason, it is considered that the bond between the polyesters becomes stronger and the film-forming property of the thermal transfer image-receiving sheet is further improved.
From the viewpoint of film forming properties of the thermal transfer image-receiving sheet, the boiling point of the glycol ethers is preferably 170 to 270 ° C, more preferably 170 to 260 ° C, and further preferably 170 to 210 ° C. From the viewpoint of volatility, the glycol ethers preferably have a vapor pressure at 20 ° C. of 30 Pa or more, more preferably 40 Pa or more, and even more preferably 50 Pa or more.

As the glycol ethers, from the viewpoint of volatility and film-forming properties of the thermal transfer image-receiving sheet, it is preferable that the terminal hydroxyl group is substituted with a substituent, and examples of the substituent include an alkyl group, an alkenyl group, and an acetyl group. Preferably used. Specifically, from the viewpoint of film forming property and volatility, ethylene glycol monobutyl ether acetate (boiling point: 192 ° C., vapor pressure: 31 Pa), diethylene glycol diethyl ether (boiling point: 188 ° C., vapor pressure: 79 Pa) and the like are preferable. It is done.
From the viewpoint of volatility and film-forming properties of the thermal transfer image-receiving sheet, the glycol ethers are preferably contained in an amount of 0.1 to 30% by weight based on the solid content of the total resin in the receiving layer composition. Preferably it is 1-30 weight%, More preferably, it is 1-20 weight%.

  In the present invention, glycol ethers are preferably used by mixing with the resin dispersion and / or a compound having an oxazoline group, and when added to the resin dispersion, during the step of producing the resin dispersion, Although it may be added at any stage after the production of the resin dispersion, it is preferably added after the production of the resin dispersion from the viewpoint of productivity. In the present invention, from the viewpoint of crosslinking reactivity between a compound having an oxazoline group and a resin containing polyester, a dispersion obtained by mixing a resin dispersion and a compound having an oxazoline group is mixed with glycol ethers. It is more preferable.

  From the viewpoint of the stability of the resin dispersion during mixing, the glycol ethers are preferably diluted with water. The dilution is performed, for example, by mixing glycol ethers and water. That is, by improving the stability of the resin dispersion at the time of mixing, the generation of aggregates is suppressed, and there is no unevenness on the printing surface of the thermal transfer image-receiving sheet obtained by the dye-receiving layer composition, A high quality image can be obtained. From the viewpoint of productivity, stability of the resin dispersion, and image quality of the thermal transfer image-receiving sheet, the mixing ratio (weight ratio) of glycol ethers and water is preferably 20/80 to 80/20 with glycol ethers / water. Preferably it is used as a mixed solution of 25/75 to 75/25, more preferably 30/70 to 70/30, and even more preferably 40/60 to 60/40.

  In-system mixing of glycol ethers with a resin dispersion and / or a compound having an oxazoline group (in the case of “resin dispersion and a compound having an oxazoline group”, these mixed dispersions are the same hereinafter) The temperature is preferably 5 to 50 ° C., more preferably 5 to 40 ° C., and still more preferably 5 to 35 ° C., from the viewpoints of miscibility between the glycol ether and the resin dispersion and the dispersibility of the resin dispersion. Specifically, the glycol ethers and the dispersions may be added and mixed at the above temperature. The rate of addition when the film-forming aid is added to the resin dispersion and / or the compound having an oxazoline group is arbitrary, but from the viewpoint of uniform mixing, the resin dispersion and / or the compound having an oxazoline group is stirred. It is preferable to add it.

((C) Compound having oxazoline group)
In the present invention, the composition for a dye-receiving layer has an oxazoline group from the viewpoint of improving releasability and heat-fusibility between a thermal transfer image-receiving sheet and a transfer sheet having a sublimable dye, and improving image density and image quality. Containing a compound having
As the compound having an oxazoline group (hereinafter sometimes referred to as “oxazoline compound”), a compound containing a plurality of oxazoline groups in the molecule can be used. As a compound containing a plurality of oxazoline groups in the molecule, bifunctional such as 2,2- (1,3-phenylene) -bis-2-oxazoline, 2,2- (1,4-phenylene) -bis-2-oxazoline, etc. Type: a polyfunctional type obtained by polymerizing a polymerizable monomer containing an oxazoline group (hereinafter sometimes referred to as an “oxazoline polymer”). From the viewpoint of cross-linking reactivity with a resin containing polyester, oxazoline Polymers are preferred.

  By using an oxazoline compound, a cross-linking effect due to a reaction with a polyester-containing resin is effectively expressed, and the cross-linking reaction is promoted, so that the molecular weight of the resin constituting the resin dispersion increases, and thermal transfer image receiving It is considered that the releasability and heat-fusibility between the sheet and the transfer sheet having a sublimable dye are improved. The oxazoline polymer can be obtained, for example, by polymerizing a polymerizable monomer containing an oxazoline group. If necessary, it can be obtained by copolymerization with a polymerizable monomer having no oxazoline group and copolymerizable with a polymerizable monomer having an oxazoline group.

  Examples of the polymerizable monomer having an oxazoline group include 2-vinyl-2-oxazoline, 2-vinyl-4-methyl-2-oxazoline, 2-vinyl-5-methyl-2-oxazoline, and 2-isopropenyl. -2-oxazoline, 2-isopropenyl-4-methyl-2-oxazoline, 2-isopropenyl-5-methyl-2-oxazoline, 2-isopropenyl-5-ethyl-2-oxazoline and the like. These may use only 1 type or may use 2 or more types together. Among these, 2-isopropenyl-2-oxazoline is preferable because it is easily available industrially.

  Examples of polymerizable monomers having no oxazoline group include methyl (meth) acrylate, ethyl (meth) acrylate, n-butyl (meth) acrylate, isobutyl (meth) acrylate, and (meth) acrylic acid. t-butyl, cyclohexyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, methoxypolyethylene glycol (meth) acrylate, lauryl (meth) acrylate, stearyl (meth) acrylate, (meth) acrylic acid- 2-hydroxyethyl, (meth) acrylic acid-2-hydroxypropyl, monoesterified product of (meth) acrylic acid and polyethylene glycol, (meth) acrylic acid-2-aminoethyl and its salt, (meth) acrylic acid Modified caprolactone, (meth) acrylic acid-2,2,6,6-tetramethyl (Meth) acrylic acid esters such as piperidine, (meth) acrylic acid-1,2,2,6,6-pentamethylpiperidine; sodium (meth) acrylate, potassium (meth) acrylate, ammonium (meth) acrylate (Meth) acrylates such as; unsaturated nitriles such as acrylonitrile and methacrylonitrile; unsaturated amides such as (meth) acrylamide, N-methylol (meth) acrylamide, and N- (2-hydroxyethyl) (meth) acrylamide Vinyl esters such as vinyl acetate and vinyl propionate; vinyl ethers such as methyl vinyl ether and ethyl vinyl ether; α-olefins such as ethylene and propylene; and halogen-containing α, β-unsaturated fats such as vinyl chloride, vinylidene chloride and vinyl fluoride Group hydrocarbons; styrene, divinylben Emissions, alpha-methyl styrene, alpha such as sodium styrene sulfonate, beta-unsaturated aromatic hydrocarbons; and the like can be given. These may be used alone or in combination of two or more.

  The weight average molecular weight of the oxazoline polymer is preferably 500 to 2,000,000, more preferably 1,000 to 1,000,000, from the viewpoints of cross-linking reactivity with the resin particles and productivity. preferable.

  In the present invention, the oxazoline compound can also be used as powder particles, but is preferably contained as dispersed or dissolved in an aqueous medium from the viewpoint of crosslinking reactivity with a resin containing polyester and productivity. . When the oxazoline compound is dispersed in an aqueous medium, the dispersed particles of the oxazoline compound have a volume median particle size (D50) of 0.02 to 1 μm from the viewpoint of crosslinking reactivity with a resin containing polyester. And more preferably 0.05 to 0.8 μm. Moreover, the above-mentioned thing is used similarly as an aqueous medium in which an oxazoline compound is disperse | distributed or melt | dissolved.

In addition, as a general commercial item of an oxazoline compound, Nippon Shokubai Co., Ltd. Epocross WS series (water-soluble type), K series (emulsion type), etc. can be used.
The content or addition amount of the oxazoline compound in the dye-receiving layer composition is from the viewpoint of cross-linking reactivity with a resin containing polyester and productivity to a solid content of 100 parts by weight with respect to 100 parts by weight of the resin containing polyester. It is preferable that it is 1-30 weight part, More preferably, it is 1-20 weight part.

  The oxazoline compound may be applied to a substrate as a coating liquid together with the resin dispersion and glycol ethers, etc., or mixed in advance with the resin dispersion and glycol ethers as a coating liquid. You may apply | coat to a base material. When mixing in advance, it is preferable to add the glycol ether or the like after mixing the resin dispersion and the oxazoline compound. The mixing of the resin dispersion and the oxazoline compound is performed in the aqueous medium with the resin dispersion. The oxazoline compound is preferably mixed at a temperature in the system at 20 to 100 ° C, more preferably at 70 to 98 ° C. Specifically, the resin dispersion is heated to the above temperature, and the oxazoline compound is added at 20 to 100 ° C., more preferably 70 to 98 ° C.

  By heating to the above temperature and mixing, at least a part of the polyester is appropriately crosslinked with the oxazoline compound. That is, in the present invention, an appropriate amount of an oxazoline compound is added to the resin dispersion and mixed at a predetermined temperature, whereby a part of the resin particles containing the polyester dispersed in the resin dispersion is crosslinked. In general, since the molecular weight of polyester increases due to crosslinking, the releasability is improved, but the film forming property tends to be inferior. However, in the present invention, it is considered that the vicinity of the surface of the resin particles containing polyester is mainly crosslinked, and the thermal transfer image-receiving sheet is separated by the interaction between the presence of polyester not crosslinked inside the particles and the film forming agent. It is thought that both moldability and film-forming property can be achieved.

Therefore, the composition for a material-receiving layer of the present invention preferably contains a crosslinked polyester in which at least a part of the compound having an oxazoline group is crosslinked at least a part of the polyester.
The presence of crosslinking of the resin containing the polyester with the oxazoline compound can be identified by analysis of the amide group generated by the crosslinking. In addition, in order to improve detection sensitivity, the insoluble matter at the time of Soxhlet extraction with tetrahydrofuran (THF) can be analyzed by FT-IR ATR (attenuated total reflection) after drying.

(Other ingredients)
The composition for a dye-receiving layer of the present invention preferably contains a release agent together with the resin dispersion, glycol ethers and oxazoline compound. As the release agent, for example, a water-dispersible or water-soluble modified silicone oil and / or a colloidal solution of silica fine particles (for example, colloidal silica) is preferably used. From the viewpoint of dispersibility in the thermal transfer image-receiving sheet, the weight average particle diameter of the above-mentioned silicic acid fine particles in the colloidal solution is preferably 100 nm or less, and more preferably 20 nm or less colloidal silica. Moreover, release agents, such as polyethylene and a polypropylene, can be contained besides the said release agent. These releasing agents are contained in the dye-receiving layer composition in an amount of 0.1 to 20 parts by weight with respect to 100 parts by weight of the resin containing the polyester, from the viewpoint of releasability and dyeing property of the thermal transfer image-receiving sheet. It is preferable that 0.5 to 10 parts by weight can be contained.

Further, the composition for a dye-receiving layer of the present invention includes titanium oxide, zinc oxide, kaolin clay, calcium carbonate, fine powder silica, etc. from the viewpoint of improving the whiteness of the dye-receiving layer and increasing the sharpness of the transferred image. Pigments and fillers. From the viewpoint of the whiteness of the thermal transfer image-receiving sheet, these pigments and fillers are used in an amount of 0.1 to 20 parts by weight, preferably 0.1 to 100 parts by weight of the resin containing polyester in the dye-receiving layer composition. -10 parts by weight.
If necessary, the composition for a dye-receiving layer may further contain additives such as a film-forming aid other than the glycol ethers, a crosslinking agent other than the oxazoline compound, a curing agent, and a catalyst.
In addition, it is preferable that the said composition for dye receiving layers does not contain surfactant from a viewpoint that resin containing polyester obtained has self-dispersibility and improves the hydrophobicity of a thermal transfer image receiving sheet.

[Thermal transfer image-receiving sheet]
The thermal transfer image receiving sheet of the present invention has a dye receiving layer containing the above dye receiving layer composition on a substrate.
(Base material)
Examples of the base material include synthetic paper (polyolefin, polystyrene, etc.), fine paper, art paper, coated paper, cast coated paper, wallpaper, backing paper, synthetic resin or emulsion-impregnated paper, synthetic rubber latex-impregnated paper, synthetic resin Various resin films or sheets such as internal paper, paperboard, cellulose fiber paper, polyolefin, polyvinyl chloride, polyethylene terephthalate, polystyrene, polymethacrylate, polycarbonate, etc. can be used. A white opaque film formed by adding an agent or a foamed foam sheet can also be used. Moreover, the laminated body which combined the said base material can also be used.
As for the thickness of these base materials, about 10-300 micrometers is common, for example. From the viewpoint of improving the adhesion to the dye-receiving layer, it is preferable to subject the surface of the substrate to primer treatment or corona discharge treatment.

(Dye-receiving layer)
As described above, the dye-receiving layer is coated on the substrate by using the dye-receiving layer composition as a coating liquid, for example, by a gravure printing method, a screen printing method, a reverse roll coating method using a gravure plate, or the like. And formed by drying. The thickness of the dye-receiving layer formed as described above is generally 1 to 50 μm, and preferably 3 to 15 μm from the viewpoint of image quality and productivity. Further, the solid content after drying is preferably 3 to 15 g per 1 m ² of the receiving layer.

A release layer containing a release agent can be formed on the dye-receiving layer from the viewpoint of further improving the release property of the thermal transfer image-receiving sheet during transfer. As a preferable release layer, it is preferable to use each modified silicone such as polyether-modified, hydroxy-modified, amino-modified, carboxy-modified, mercapto-modified, etc., and this modified silicone can be crosslinked using a crosslinking agent as necessary. Also good.
The thermal transfer image-receiving sheet of the present invention is obtained by forming the dye-receiving layer on at least one surface of the substrate.

[Method for producing dye-receiving layer composition and method for producing thermal transfer image-receiving sheet]
The method for producing a dye-receiving layer composition of the present invention comprises (I) a step of obtaining a resin dispersion of a resin containing polyester in an aqueous medium, and (II) (a) the resin obtained in step (I). A step of mixing a dispersion, (b) a glycol ether having a boiling point of 160 to 280 ° C. and a vapor pressure at 20 ° C. of 20 Pa or more, and (c) a compound having an oxazoline group. is there. The method for producing a thermal transfer image-receiving sheet of the present invention includes (I) a step of obtaining a resin dispersion of a resin containing polyester in an aqueous medium, and (II) (a) a resin dispersion obtained in step (I). (B) A glycol ether having a boiling point of 160 to 280 ° C. and a vapor pressure at 20 ° C. of 20 Pa or more, and (c) a compound having an oxazoline group are mixed to prepare a composition for a dye receiving layer. And (III) providing a dye-receiving layer containing the dye-receiving layer composition obtained in step (II) on the substrate.

  Method of obtaining resin dispersion by emulsifying resin containing polyester in resin containing polyester, resin dispersion and aqueous medium in step (I), and glycol ethers and compound having oxazoline group in step (II) Furthermore, the substrate, the dye-receiving layer and the like in the step (III) are as described above. The method for mixing the resin dispersion, the glycol ethers and the compound having an oxazoline group, and the method for providing the dye-receiving layer on the substrate are also as described above. In the present invention, in the above step (II), the glycol ether of (b) is preferably diluted with water. The dilution is performed, for example, by mixing glycol ethers and water. From the viewpoints of productivity, stability of the resin dispersion, and image quality of the thermal transfer image-receiving sheet, the glycol ethers are 20/80 to 80/20, more preferably 25/75 to water, preferably glycol ethers / water. It is preferably used as a mixed solution obtained by mixing at a ratio (weight ratio) of 75/25, more preferably 30/70 to 70/30, and even more preferably 40/60 to 60/40.

[Thermal transfer method]
In the present invention, a transfer sheet having a sublimation dye is pressure-bonded under heating to the receiving layer surface of the thermal transfer image-receiving sheet provided with the above-mentioned receiving layer on the above-mentioned substrate, and the transferred image is obtained by transferring the dye. .
The transfer sheet used when performing thermal transfer using the thermal transfer image-receiving sheet using the dye-receiving layer composition of the present invention is usually a paper or polyester film provided with a dye layer containing a sublimation dye. Yes, any conventionally known transfer sheet can be used.

Examples of sublimable dyes that can be suitably used for the thermal transfer image-receiving sheet of the present invention include pyridoneazo series, dicyanostyryl series, quinophthalone series, merocyanine series for yellow dyes; benzeneazo series, pyrazolone azomethine series, isothiazole series for magenta dyes, Pyrazolotriazole series: As cyan dyes, anthraquinone series, cyanomethylene series, indophenol series, and indonaphthol series are listed.
As the means for applying thermal energy at the time of thermal transfer, any conventionally known means for applying can be used. For example, by controlling the recording time with a recording device such as a thermal printer, it is about 5 to 100 mJ / mm ² . This can be done by applying thermal energy.

Hereinafter, the present invention will be described more specifically with reference to examples and the like. In the following examples and the like, each property value was measured and evaluated by the following method.
[Acid value of resin]
Measured according to JIS K0070. However, as a measurement solvent, a mixed solvent of ethanol and ether was a mixed solvent of acetone and toluene (acetone: toluene = 1: 1 (volume ratio)).

[Softening point and glass transition point of polyester]
(1) Using a flow tester (manufactured by Shimadzu Corporation, “CFT-500D”), a 1 g sample was heated at a rate of temperature increase of 6 ° C./min, a load of 1.96 MPa was applied by a plunger, a diameter of 1 mm, a length Extrude from a 1 mm nozzle. Plot the flow tester drop by the flow tester against the temperature, and let the softening point be the temperature at which half the sample flowed out.
(2) Glass transition point Using a differential scanning calorimeter (Perkin Elmer, Pyris6DSC), the temperature was raised to 200 ° C., and the sample cooled to 0 ° C. at a temperature lowering rate of 10 ° C./min from that temperature was heated to 10 ° C. The temperature is increased at a rate of 1 min / min, and the temperature is defined as the intersection of a base line extension below the maximum peak temperature of endotherm and a tangent line indicating the maximum slope from the peak rising portion to the peak apex.

[Number average molecular weight of resin]
The molecular weight distribution is measured by gel permeation chromatography and the number average molecular weight is calculated by the following method.
(1) Preparation of sample solution The resin is dissolved in tetrahydrofuran (THF) so that the concentration is 0.5 g / 100 ml. Subsequently, this solution is filtered using a fluororesin filter having a pore size of 2 μm [manufactured by Sumitomo Electric Industries, Ltd., “FP-200”] to remove insoluble components to obtain a sample solution.
(2) Molecular weight distribution measurement Using the following apparatus, THF is flowed at a flow rate of 1 ml per minute, and the column is stabilized in a constant temperature bath at 40 ° C. 100 μl of the sample solution is injected therein and measurement is performed. The molecular weight of the sample is calculated based on a calibration curve prepared in advance. The calibration curve at this time includes several types of monodisperse polystyrene (2.63 × 10 ³ , 2.06 × 10 ⁴ , 1.02 × 10 ⁵ manufactured by Tosoh Corporation, and 2.10 × 10 ³ manufactured by GL Sciences, Inc. , 7.00 × 10 ³ , 5.04 × 10 ⁴ ) are used as standard samples.
Measuring device: CO-8010 (manufactured by Tosoh Corporation)
Analysis column: GMHLX + G3000HXL (manufactured by Tosoh Corporation)

[Particle Size of Resin Particles Containing Polyester in Resin Dispersion]
Using a laser diffraction particle size analyzer (HORIBA, "LA-920"), add distilled water to the measurement cell and measure the volume-median particle size (D50) at a concentration where the absorbance is in the proper range. To do.

[Solid concentration of resin dispersion]
Using an infrared moisture meter (Ketto Science Laboratory Co., Ltd .: FD-230), 5 g of the dispersion was wet at a drying temperature of 150 ° C. and a measurement mode 96 (monitoring time 2.5 minutes / variation width 0.05%). Measure the moisture content of the base. The solid content concentration was calculated according to the following formula.
Solid content concentration (%) = 100-M
M: wet base moisture (%) = [(W−W ₀ ) / W] × 100
W: Sample weight before measurement (initial sample weight)
W ₀ : Sample weight after measurement (absolute dry weight)

Production Example 1 (Production of polyester a)
Polyoxypropylene (2.2) -2,2-bis (4-hydroxyphenyl) propane 17,500 g, polyoxyethylene (2.0) -2,2-bis (4-hydroxyphenyl) propane 16,250 g, 11,454 g of terephthalic acid, 1,608 g of dodecenyl succinic anhydride, 4,800 g of trimellitic anhydride and 15 g of dibutyltin oxide were placed in a four-necked flask equipped with a nitrogen inlet tube, a dehydrating tube, a stirrer and a thermocouple, The mixture was stirred at 220 ° C. in a nitrogen atmosphere and reacted until the softening point measured according to ASTM D36-86 reached 120 ° C. to obtain polyester a. The obtained polyester a had a softening point of 125 ° C., a glass transition point of 65 ° C., an acid value of 19 mgKOH / g, and a number average molecular weight of 3580.

Production Example 2 (Production of polyester b)
525 g of polyoxypropylene (2.2) -2,2-bis (4-hydroxyphenyl) propane, 1,950 g of polyoxyethylene (2.0) -2,2-bis (4-hydroxyphenyl) propane, terephthalic acid 1,552 g, glycerin 138 g and tin octylate 21 g were put into a four-necked flask equipped with a nitrogen introduction tube, a dehydration tube, a stirrer and a thermocouple, stirred at 220 ° C. in a nitrogen atmosphere, and measured according to ASTM D36-86. Reaction was performed until the softening point reached 120 ° C. to obtain polyester b. The obtained polyester b had a softening point of 121 ° C., a glass transition point of 73 ° C., an acid value of 21 mgKOH / g, and a number average molecular weight of 3870.

Production Example 3 (Production of polyester c)
3920 g of polyoxypropylene (2.2) -2,2-bis (4-hydroxyphenyl) propane, 1560 g of polyoxyethylene (2.0) -2,2-bis (4-hydroxyphenyl) propane, dodecenyl succinic anhydride 1672 g, 1354 g of terephthalic acid, and 25 g of tin octylate are placed in a four-necked flask equipped with a nitrogen introduction tube, a dehydration tube, a stirrer, and a thermocouple, and are reacted at 230 ° C. under normal pressure for 5 hours under a nitrogen atmosphere. It reacted with. Trimellitic anhydride 307 g was added and reacted until the softening point measured according to ASTM D36-86 reached 120 ° C. to obtain polyester c. The obtained polyester c had a softening point of 115 ° C., a glass transition point of 57 ° C., an acid value of 15 mgKOH / g, and a number average molecular weight of 4200.

Production Example 4 (Production of polyester-containing resin dispersion a)
300 g of polyester a was placed in a four-necked flask equipped with a nitrogen inlet tube, a reflux condenser, a stirrer, and a thermocouple, and dissolved in 540 g of methyl ethyl ketone at 25 ° C. Next, 6.95 g of 25% aqueous ammonia was added, 716 g of deionized water was added with stirring, and then methyl ethyl ketone was distilled off at 50 ° C. under reduced pressure to obtain a polyester dispersion a. The volume median particle size of the resin particles in the obtained dispersion a was 120 nm, the solid content was 29.7%, the pH was 7.4, the softening point was 118 ° C., and the glass transition point was 61 ° C. .

Production Example 5 (Production of resin dispersion b containing polyester)
300 g of polyester resin A was placed in a four-necked flask equipped with a nitrogen inlet tube, a reflux condenser, a stirrer, and a thermocouple, and dissolved in 540 g of methyl ethyl ketone at 40 ° C. Next, 7.64 g of 25% aqueous ammonia was added, 720 g of deionized water was added with stirring, and then methyl ethyl ketone was distilled off at 50 ° C. under reduced pressure to obtain a resin dispersion b. The resin particles in the obtained resin dispersion b had a volume median particle size of 610 nm, a solid content of 30% by weight, a pH of 7.6, a softening point of 120 ° C., and a glass transition point of 70 ° C. .

Production Example 6 (Production of resin dispersion c containing polyester)
In a four-necked flask equipped with a nitrogen introduction tube, a reflux condenser, a stirrer, and a thermocouple, 2000 g of polyester resin c was dissolved in 3600 g of methyl ethyl ketone at 25 ° C. Next, 32.5 g of 25% aqueous ammonia was added, 4667 g of deionized water was added with stirring, and then methyl ethyl ketone was distilled off at 50 ° C. under reduced pressure to obtain a resin dispersion c. The resin particles in the obtained resin dispersion c had a volume median particle size of 125 nm, a solid content of 36% by weight, and a pH of 7.7.

Production Example 7 (Production of mixed dispersion A of resin dispersion a containing polyester and oxazoline polymer)
700 g of resin dispersion a containing polyester, oxazoline polymer (Epocross WS-700 manufactured by Nippon Shokubai Co., Ltd., oxazoline group content in the oxazoline polymer: 4.55 mmol / g, number average molecular weight: 20,000, weight average molecular weight: 40,000, 25% aqueous solution) 62.29 g was put into a four-necked flask equipped with a nitrogen inlet tube, a reflux condenser, a stirrer, and a thermocouple, and reacted at 95 ° C. for 4 hours with stirring. Obtained. The volume median particle size of the resin particles in the obtained mixed dispersion A was 120 nm, the solid content was 31.2%, the pH was 8.8, the softening point was 225 ° C., and the glass transition point was 58 ° C. It was.

Production Example 8 (Production of mixed dispersion C of polyester-containing resin dispersion c and oxazoline polymer)
700 g of a resin dispersion c containing polyester and 59.3 g of an oxazoline-containing polymer (Epocross WS-700 manufactured by Nippon Shokubai Co., Ltd.) are placed in a four-necked flask equipped with a nitrogen inlet tube, a reflux condenser, a stirrer, and a thermocouple. The mixture was reacted at 95 ° C. for 4 hours with stirring to obtain a mixed dispersion C. The volume median particle size of the resin particles in the obtained mixed dispersion C was 107 nm, the solid content was 36.0%, the pH was 8.7, the softening point was 219 ° C., and the glass transition point was 54 ° C. It was.

Examples 1 to 6 and Comparative Examples 1 to 6 (Production of Receptive Layer Compositions A to L)
The resin dispersion, the glycol ethers shown in Table 1, and the release agent were mixed at 25 ° C. as shown in Table 2 to obtain dye receiving layer compositions A to L, respectively. In addition, the number in Table 2 is the addition amount of each component, and represents the number of grams.

Each of the dye receiving layer compositions A to L was applied to a synthetic paper (YGS Corporation FGS250) at 25 ° C. using a wire bar so that the coating amount after drying was 5.0 g / m ^2. It was dried at 2 ° C. for 2 minutes to obtain a thermal transfer image receiving sheet. A solid black image was printed on this thermal transfer image-receiving sheet using a sublimation printer (SELPHY, manufactured by Canon Inc.). For each of these photographic papers, the image density, heat-fusibility (releasability from paper) and image quality (smoothness of the photographic paper surface) were measured and evaluated as follows. The results are shown in Table 2.

Evaluation method [Image density]
The image density of the black solid part was measured with a Gretag densitometer (manufactured by GRETAG-MACBETH).
[Heat fusion (Evaluation of releasability from transfer sheet)]
From the peeling sound of the ink ribbon and the dye image-receiving sheet at the time of gradation pattern printing, the thermal fusing property was judged according to the following criteria.
1: There is no abnormal noise at the time of peeling, and there is no problem due to thermal fusion between the thermal transfer image receiving sheet and the ink ribbon. 2: Although some abnormal noise is heard at the time of peeling, there is no problem due to thermal fusion. 3: Heat Fusing and difficult to peel

[Image quality (smoothness of photographic paper surface)]
The state of occurrence of aggregates due to the addition of the film-forming aid was judged from the unevenness of the photographic paper surface in the image evaluation.
1: The surface state is very smooth visually.
2: Although slight unevenness is confirmed by visual observation, it is a level that does not cause any problem in actual use as a photograph.
3: A considerable agglomerate can be confirmed by visual observation, and there is a problem in use as a photograph.

  The thermal transfer image-receiving sheet using the composition for the receiving layer of the present invention can be dried at a low temperature and in a short time, has excellent heat-fusibility, has excellent printing sensitivity, and can obtain a high-density image. It can be suitably used as a thermal transfer image receiving sheet having excellent image performance.

Claims (8)

(A) a resin dispersion of a resin containing polyester, (b) a glycol ether having a boiling point of 160 to 280 ° C. and a vapor pressure at 20 ° C. of 20 Pa or more, and (c) a compound having an oxazoline group A dye-receiving layer composition for a thermal transfer image-receiving sheet , comprising:
Polyester is of formula (1)

(In the formula, RO is an oxyalkylene group, R is an ethylene group and / or propylene group, x and y represent the number of added moles of alkylene oxide, each is a positive number, and the sum of x and y) Is an average value of 2 to 7.)
A dye comprising a polyester obtained by condensation polymerization of an alcohol component containing 50 mol% or more of an alkylene oxide adduct of 2,2-bis (4-hydroxyphenyl) propane represented by the formula: Composition for receiving layer.   The dye receiving layer composition according to claim 1, wherein at least a part of the compound having an oxazoline group contains a crosslinked polyester obtained by crosslinking at least a part of the polyester.   The composition for a dye-receiving layer according to claim 1 or 2, wherein the polyester is obtained by condensation polymerization of an alcohol component and a carboxylic acid component containing 50 mol% or more of an aromatic dicarboxylic acid.   The polyester is obtained by condensation polymerization of an alcohol component and a carboxylic acid component containing 5 to 50 mol% of succinic acid having an alkyl group and / or an alkenyl group. A composition for a dye-receiving layer as described in 1. (I) a step of obtaining a resin dispersion of a resin containing polyester in an aqueous medium, and (II) (a) the resin dispersion obtained in step (I), (b) having a boiling point of 160 to 280 ° C. And a step of mixing a glycol ether having a vapor pressure at 20 ° C. of 20 Pa or more and (c) a compound having an oxazoline group,
A method for producing a dye-receiving layer composition for a thermal transfer image-receiving sheet , comprising:
Polyester is of formula (1)

(In the formula, RO is an oxyalkylene group, R is an ethylene group and / or propylene group, x and y represent the number of added moles of alkylene oxide, each is a positive number, and the sum of x and y) Is an average value of 2 to 7.)
A dye comprising a polyester obtained by condensation polymerization of an alcohol component containing 50 mol% or more of an alkylene oxide adduct of 2,2-bis (4-hydroxyphenyl) propane represented by the formula: A method for producing a composition for a receiving layer. In step (II), (b) a glycol ether having a boiling point of 160 to 280 ° C. and a vapor pressure at 20 ° C. of 20 Pa or more is treated with water and 20/80 to 80/20 (the glycol ether). The production method according to claim 5 , wherein the mixture is a mixture obtained by mixing at a weight ratio. The thermal transfer image receiving sheet which has a dye receiving layer containing the composition for dye receiving layers in any one of Claims 1-4 on a base material. (I) a step of obtaining a resin dispersion of a resin containing polyester in an aqueous medium;
(II) (a) the resin dispersion obtained in step (I), (b) glycol ethers having a boiling point of 160 to 280 ° C. and a vapor pressure at 20 ° C. of 20 Pa or more, and (c) ) A step of mixing a compound having an oxazoline group to obtain a composition for a dye receiving layer; and
(III) a step of providing a dye-receiving layer containing the dye-receiving layer composition obtained in step (II) on the substrate;
A method for producing a thermal transfer image-receiving sheet comprising :
Polyester is of formula (1)

(In the formula, RO is an oxyalkylene group, R is an ethylene group and / or propylene group, x and y represent the number of added moles of alkylene oxide, each is a positive number, and the sum of x and y) Is an average value of 2 to 7.)
Thermal transfer, comprising a polyester obtained by condensation polymerization of an alcohol component containing 50 mol% or more of an alkylene oxide adduct of 2,2-bis (4-hydroxyphenyl) propane represented by A method for producing an image receiving sheet.