JP2008246918A - Method for producing thermal transfer image-receiving sheet - Google Patents

Abstract

The present invention provides a method for producing a thermal transfer image receiving sheet capable of producing a thermal transfer image receiving sheet capable of obtaining a high transfer density and suppressing occurrence of cracks after coating.
A method for producing a thermal transfer image-receiving sheet having a heat insulating layer containing a hollow polymer, a polymer latex, and a receiving layer containing a water-soluble polymer on a support, wherein the coating solution for forming the receiving layer is a polymer. A receiving layer coating solution having a glass transition temperature of latex of 70 ° C. or lower and a solid content of the water-soluble polymer of 0.01% by mass to 3% by mass, including the receiving layer coating solution 2 A coating layer was formed by coating a plurality of coating liquids on the support with simultaneous multilayer coating, a drying process for drying the coating layer, a transporting process for transporting the coating layer at a film surface temperature of 35 ° C. or less. And a winding process for winding the support, and a method for producing a thermal transfer image-receiving sheet in which the time from the end of the drying process to the start of the winding process is within 10 minutes.
[Selection figure] None

Description

  The present invention relates to a method for producing a thermal transfer image receiving sheet. More specifically, the present invention relates to a method for producing an image-receiving sheet for thermal transfer, in which cracking after coating is suppressed and white spots after printing are small.

  Conventionally, various thermal transfer recording methods are known. 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. In addition, it has advantages such as being dry, being able to be visualized directly from digital data, and being easy to produce duplicates compared to silver salt photography.

  In this dye diffusion transfer recording system, a heat-sensitive transfer sheet containing a pigment (hereinafter also referred to as an ink sheet) and a heat-sensitive 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. Because of such a recording method, the image-receiving sheet needs not only to have a high density after transfer, but also to have a good surface condition after coating, and white spots after printing due to surface defects are caused. Not required.

  The image-receiving sheet has been conventionally produced by applying a receiving layer, an intermediate layer, a heat insulating layer and the like by applying a solvent and then bonding them. However, in recent years, due to environmental considerations, it has been carried out by applying a coating solution such as a receiving layer, an intermediate layer, a heat insulating layer, and an undercoat layer on a support by aqueous coating. Further, in recent years, the image-receiving sheet is produced by using a water-soluble polymer in the aqueous coating.

In the image receiving sheet prepared by this aqueous coating, the lower the glass transition temperature (Tg) of the polymer latex contained in the receiving layer is effective for increasing the transfer density. However, the receiving layer containing the low Tg polymer latex has a tendency to crack when dried after coating (see, for example, Patent Document 1 or Patent Document 2).
JP 2006-88691 A JP 2006-68918 A

  When producing an image receiving sheet by aqueous coating as described above, it has been difficult to achieve both high transfer density and suppression of cracks.

  It is an object of the present invention to provide a method for producing a thermal transfer image receiving sheet capable of obtaining a high transfer density and capable of producing a thermal transfer image receiving sheet in which cracking after coating is suppressed. .

As a result of intensive investigations, the present inventors have conducted film surface temperature management suitable for the physical properties of the thermal image-receiving sheet coating liquid, thereby suppressing the occurrence of cracks, reducing white spots after printing, and impairing the transfer density. It has been found that a thermal transfer image-receiving sheet can be obtained.
That is, the said subject was achieved by the following means.
<1> On a support, at least one heat insulating layer containing at least one hollow polymer, and at least one receiving layer containing at least one polymer latex and at least one water-soluble polymer. A method for producing a thermal transfer image-receiving sheet having at least a coating liquid for forming the receiving layer, wherein the polymer latex has at least one glass transition temperature of 70 ° C. or less, and the water-soluble polymer with respect to the total solid content. Is a coating solution for forming a receiving layer having a content of 0.01% by mass or more and 3% by mass or less, and two or more types of coating solutions containing the coating solution for forming a receiving layer are applied simultaneously on the support. A step of drying, a drying step of drying the coating layer coated with the simultaneous multilayer coating, a transporting step of transporting the film surface temperature of the coating layer to 35 ° C. or less after the drying step, and the transporting step And a winding step for winding the support on which the coating layer formed is conveyed, and the time from the end of the drying step to the start of the winding step is within 10 minutes.
<2> The feeling according to <1>, wherein the content of the water-soluble polymer with respect to the total solid content of the coating liquid for forming a receiving layer is 0.01% by mass or more and 1% by mass or less. A method for producing a thermal transfer image-receiving sheet.

  According to the present invention, it is possible to provide a method for producing a thermal transfer image receiving sheet capable of obtaining a high transfer density and capable of producing a thermal transfer image receiving sheet in which cracking after coating is suppressed. .

Hereinafter, the present invention will be described in detail.
The heat-sensitive transfer image-receiving sheet of the present invention has at least one heat insulating layer containing at least one hollow polymer on a support, at least one receiving layer containing at least one polymer latex and at least one water-soluble polymer. A heat-sensitive transfer image-receiving sheet having one layer. Each of the heat insulating layer and the receiving layer may be formed of a plurality of layers. An intermediate layer such as a white background adjustment layer, a charge control layer, an adhesive layer, a primer layer, or an undercoat layer is formed between the support and the heat insulation layer and / or between the heat insulation layer and the receiving layer. Also good. In addition, a release layer may be formed on the outermost layer on the surface overlapped with the transfer material.
Further, it is preferable that a curl adjusting layer, a writing layer, and a charge adjusting layer are formed on the back side of the support (at least the side opposite to the side on which the heat insulating layer and the receiving layer are provided).

These heat-sensitive transfer image-receiving sheets are prepared by preparing a coating solution, applying the coating solution on a support, and drying. In the present invention, the receptor layer and the heat insulating layer are each preferably two layers or more, or one of the layers is preferably two or more layers. However, at least two kinds of coating liquids containing at least a receptor layer forming coating liquid are simultaneously formed on the support. At least a receiving layer is formed by applying multiple layers. The layer formed together with the receiving layer may be a heat insulating layer or an intermediate layer having other functions. When the intermediate layer is included, the receiving layer, the heat insulating layer and the intermediate layer can be formed by simultaneous multilayer coating.
In the present invention, when the receiving layer is formed without simultaneous multilayer coating, the coated surface of the receiving layer is deteriorated.
Hereinafter, this process will be described in detail.

(Preparation of coating solution)
The coating liquid preparation step includes a step of preparing and weighing various emulsions and additives used in the coating solution, and a step of adding and mixing these to prepare a coating solution.
There are methods such as weight measurement and volume measurement for measuring the emulsion and additives, and any of these methods can be used.
As a method for preparing the coating solution, for example, it is roughly classified into two types, a continuous preparation method and a batch preparation method. Any method can be used for producing the thermal transfer image-receiving sheet.

  The continuous liquid preparation method is a method for preparing a coating liquid characterized in that necessary additives are sequentially or simultaneously added at a constant ratio to a reference liquid when a reference liquid is flowing at a constant flow rate. The merit of the continuous liquid preparation method is that the elapsed time of the coating liquid is uniform and the product performance is stabilized. On the other hand, the disadvantage is that there is a large loss until a steady state is reached. Moreover, it is unsuitable for the prescription which requires reaction waiting time, such as reaction and adsorption | suction at the time of preparation.

  The batch preparation method is a more general method, and is a batch method in which a dispersion and an additive are mixed in a container such as a kettle using a stirring / mixing device. This method has advantages that it is easy to set time corresponding to reaction, adsorption, and the like, and it is easy to take countermeasures such as strengthening stirring and shortening the preparation cycle. On the contrary, as a demerit, it is mentioned that the elapsed time of the coating liquid is not constant.

In the batch preparation method, in addition to a preparation tank for preparing a coating liquid, a stock tank, a unit for measuring liquid properties, a transfer pump and a filtration device, a liquid level measuring unit, and the like may be provided. As the liquid level meter, various methods such as a differential piezoelectric transmitter, an ultrasonic level meter, a follow-up level meter, and a load cell are known, but any method can be adopted as long as the liquid amount can be measured. A unit for measuring liquid properties is often provided in a stock tank. Furthermore, a buffer tank for sending the coating liquid to the coating process may be provided. After confirming that there is no abnormality in the physical properties of the liquid preparation in the stock tank, the liquid is transferred. A filtration device may be provided between the preparation liquid stock tank and the buffer tank. These tanks may be scaleable.
In the preparation tank, the necessary coating liquid (emulsion, various chemicals, etc.) is sequentially added according to the coating liquid formulation.

The preparation tank often has a temperature-adjustable jacket, and the added chemicals are mixed uniformly by a stirrer. As the stirring blade, various commercially available stirring blades such as a propeller, a paddle, a jet type, and an anchor type can be used. The stirring flow can be either a down flow type or an up flow type.
A device that controls the rotation speed of the stirrer in the coating liquid preparation tank so that the same stirring and mixing efficiency can be obtained in each scale of the prepared liquid, and a vortex generated when the liquid volume is low reaches the stirring blade and is generated In order to prevent foaming, baffles may be provided on the inner surface of the tank and / or around the stirring blades. These widen the practical stirring area.

(Gelatin dissolution)
When gelatin is added to the coating solution, it is preferable to dissolve gelatin in advance. The gelatin dissolution method is as follows: 1) A swelling and dissolution method in which the whole powder is swollen by dispersing and immersing in water at room temperature, and then the temperature is dissolved by heating. 2) Gelatin is charged into warm water and immediately heated. There are high-temperature dissolution methods in which high-speed stirring is used for dissolution, and 3) other methods, but any method can be used without any particular limitation.

(Measurement of liquid properties)
Various viscometers, surface tension measuring devices, specific gravity meters, pH meters and the like can be used for measuring the liquid physical properties of the coating liquid. For pH measurement, a pH meter using a glass electrode calibrated with a standard buffer for pH can be used.

(Application)
The application of each layer can be appropriately selected from known methods such as roll coating, bar coating, gravure coating, gravure reverse coating, die coating, slide coating, curtain coating and the like that allow simultaneous multilayer coating. Among these, curtain coating and slide coating are methods in which the coating film thickness is determined by the flow rate of liquid delivered by a pump or the like, and simultaneous multilayer coating is possible.

  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-B-49-7050, each specification or Edgar B. Gutoff et al., “Coating and Drying Defects: Troubleshooting Operating Problems”, John Wiley & Sons, In 1995, the so-called slide coating (slide coating method) and curtain coating (curtain coating method) described in pages 101 to 103 are known. In these coating methods, a plurality of coating liquids are simultaneously supplied to a coating apparatus to form a plurality of different layers. These methods can obtain a uniform coating film thickness and can simultaneously apply multiple layers, and can be preferably used in the present invention.

As an apparatus for the slide coating method, there is a multilayer slide bead apparatus proposed in US Pat. No. 2,761,791 by Russell et al. Examples of coater shapes are described, for example, in “LIQUID FILM COATING” (CHAPMAN & HALL, 1997) by Stephen F. Kistler and Petert M. Schweizer.
The slide bead coating apparatus mainly includes a coating head and a backup roller that wraps and supports a continuously running support. Inside the block that forms the coating head, there is formed a liquid pool that spreads the coating liquid fed from the liquid feeding line in the width direction of the support, and a narrow slit communicates with this liquid pool up to the slide surface. An opening is formed. This slide surface is formed on the upper surface of the coating head and is inclined downward toward the backup roller side.

  The coating liquid supplied to each liquid reservoir is pushed out from each slit to the slide surface, and sequentially overlaps while flowing down the slide surface to form a multi-layer coating film. Reach the tip of the lower end. The coating liquid that has reached the tip forms a coating liquid bead in the gap between the tip and the support surface that is wound around the backup roller and travels, and is applied to the support surface via the coating liquid bead. The lower part is depressurized to stabilize the bead. Therefore, a decompression chamber is formed below the backup roller. The decompression chamber serves to stabilize the bead by setting the lower side of the bead to a negative pressure and to make it easier for excess coating liquid not applied to the web to flow down into the decompression chamber. In this process, as described above, it is necessary to prevent one coating solution of adjacent layers from adversely affecting the coating solution of the other layer or between the coating solutions.

  Curtain coating is a method of coating a free-falling liquid film on a support that is continuously running at a constant speed. There are several methods such as an extrusion type and a slide type. In the slide type coater, the multilayer liquid film created on the slide surface falls freely from the slide end. Therefore, the shape of the slide surface is devised so that a falling liquid film is smoothly formed.

  In simultaneous multi-layer coating, it is necessary to adjust the viscosity and surface tension of the coating solution constituting each layer from the viewpoints of forming a uniform coating film and good coating properties. The viscosity of the coating solution can be easily adjusted by using a known thickener or thickener within a range that does not affect other performances. Further, the surface tension of the coating solution can be adjusted by various surfactants.

In order to feed a coating solution prepared so that the physical properties such as liquid concentration, viscosity, surface tension, pH, etc. are appropriate values, it is necessary to continuously carry out while removing bubbles and foreign substances. is there.
Various methods are possible for continuously supplying the coating liquid at a constant flow rate, but it is preferable to use a metering pump from the viewpoint of accuracy and reliability. Examples include a plunger pump and a diaphragm pump. In the diaphragm type, the plunger and the liquid to be sent are separated by the two diaphragms, and the operation of the plunger is transmitted to the liquid to be sent via the drive oil and the pure water between the two diaphragms. It is done. Variations in the flow rate of the liquid feed pump lead to variations in the coating film thickness, and sufficient accuracy is required.
When it is necessary to reduce the influence of the pump pulsation, an auxiliary device for absorbing the pulsation is used. Some methods are publicly known, but a pipeline type pulsation absorbing device can be cited as an example (for example, see Japanese Patent Laid-Open No. 1-255793).

  In order to remove foreign matter, it is preferable to filter the coating solution. Various kinds of filter media can be used, and a cartridge filter medium can be given as an example. In use, it is preferable to treat in advance in order to prevent air retained in the pores of the filter medium from being mixed into the coating liquid in the form of bubbles. Although several methods are known, as an example, treatment with a liquid containing a surfactant or the like (see, for example, US Pat. No. 5,096,602) can be mentioned.

  Along with foreign matter, bubbles also cause coating surface failure. For this reason, it is preferable to defoam and defoam bubbles that are mixed in the coating liquid and foams that are floating on the liquid surface. As a technique for this purpose, there is separation of bubbles from liquid or dissolution of bubbles in liquid. As separation methods, vacuum defoaming, ultrasonic defoaming, centrifugal defoaming and the like are known. Examples of the method for dissolving in a liquid include ultrasonic pipeline defoaming.

  When using an additive that deteriorates the aging stability of the coating solution by adding it to the coating solution, in order to shorten the aging time from adding to coating, A method of adding just before is known. Such a method can also be used in the present invention. As a mixer for this purpose, there are a static mixer and a dynamic mixer.

(Dry)
After coating, the coated product having a coating film formed on the support is dried in a drying zone and wound up through a humidity control zone. In the present invention, it is preferable to solidify immediately after forming a coating film having a multilayer structure comprising a plurality of layers on a support.
In the present invention, the time when the drying is completed is defined as a drying point. In the present invention, after the drying point, the film surface temperature until the film is wound up by a roll after the conveyance process is required to be 35 ° C. or less. . Thereby, generation | occurrence | production of a crack can be suppressed more effectively.
The film surface temperature in the transfer process can be set to 35 ° C. or less, for example, by setting the drying temperature to 35 ° C. or less and appropriately controlling the environmental temperature in the transfer process.
Further, it is better from the viewpoint of productivity and efficiency that the time from the drying point to the start of winding is small, and it is necessary that the winding is started within 10 minutes.

In addition, when a strong dry air is applied at a stage where the coating film is not sufficiently solidified, fluidity is generated, resulting in unevenness. Further, when the uppermost layer of the coating film contains an organic solvent, nonuniform solvent evaporation occurs on the slide surface or immediately after coating due to the wind, resulting in unevenness. From this point of view, aqueous coating is advantageous.
In addition, when a binder that gels at a low temperature such as gelatin is formed, the temperature is quickly lowered after forming a plurality of layers on the support, the coating is cooled and solidified (setting process), and then the temperature is raised and dried. Is preferred. Thereby, a further uniform and homogeneous coating film is formed. Here, the setting step is, for example, a gelation accelerating step for increasing the viscosity of the coating composition by means of lowering the temperature by applying cold air or the like to the coating and slowing the material fluidity in each layer and each layer. Means that. In the present invention, this method can be preferably used.

  In the present invention, since the main component of the coating solution is composed of polymer latex, if it is dried quickly, the film shrinks due to drying, and the coating film after drying tends to crack. Is preferred. In order to satisfy such requirements, the drying process needs to be dried while adjusting the drying speed, adjusting the drying temperature, the amount of drying air, and the dew point of the drying air.

As a typical drying apparatus, there are an air loop method, a hanger method, and the like.
The air loop method is a method in which a dry air jet is blown onto a coated product supported by a roller, and there are a method in which a duct is arranged vertically and a method in which a duct is arranged horizontally. The drying function and the transport function are basically separated, and the degree of freedom such as the air volume is large. However, since many rollers are used, poor conveyance of the base (support) such as shift, wrinkle, and slip tends to occur.
The spiral winding method is a method in which a coated product is wound around a cylindrical duct in a spiral shape and floated with dry air (air floating) and transported and dried. Basically, no support is required for the roller (for example, And Japanese Patent Publication No. 43-20438).
In the present invention, these drying apparatuses can be preferably used.

(1) Thermal Transfer Image Receiving Sheet Hereinafter, the configuration of the thermal transfer image receiving sheet in the present invention will be described in detail.
(Receptive layer)
In the present invention, the receiving layer contains at least one polymer latex and at least one water-soluble polymer. At least one of the polymer latexes needs to have a glass transition temperature of 70 ° C. or lower. The receiving layer-forming coating solution for forming the receiving layer contains a water-soluble polymer of 0.01% or more and 3% or less in terms of the total solid content, and the content is 0.01% or more and 1%. The following is more preferable.

The receiving layer serves to receive the dye transferred from the ink sheet and maintain the formed image. In the heat-sensitive transfer image-receiving sheet of the present invention, the receiving layer contains at least one polymer latex.
The receiving layer can contain an ultraviolet absorber, a release agent, a lubricant, an antioxidant, a preservative, a surfactant, and other additives.

<Polymer latex>
The polymer latex used in the present invention will be described. In the heat-sensitive transfer image-receiving sheet of the present invention, the polymer latex that can be used in the receiving layer is a dispersion of a hydrophobic polymer insoluble in water as fine particles in a water-soluble dispersion medium. As the dispersion state, the polymer is emulsified in a dispersion medium, the emulsion is polymerized, the micelle is dispersed, or the polymer molecule has a partially hydrophilic structure and the molecular chain itself is molecularly dispersed. And may be in any dispersed state. Regarding polymer latex, for example, Tadashi Okuda, Hiroshi Inagaki, “Synthetic Resin Emulsion”, published by Kobunshi Publishing (1978); Takaaki Sugimura, Ikuo Kataoka, Junichi Suzuki, Keiji Kasahara, “Application of Synthetic Latex” Published by Polymer Publishing Co. (1993); Soichi Muroi, “Chemistry of Synthetic Latex”, published by Polymer Publishing Co. (1970); supervised by Yoshiaki Mitsuzawa, “Development and Application of Aqueous Coating Materials”, See It is described in MC Publishing (2004) and JP-A-64-538. The average particle size of the dispersed particles in the polymer latex is preferably in the range of 1 to 50000 nm, more preferably about 5 to 1000 nm.
The particle size distribution of the dispersed particles is not particularly limited, and may have a wide particle size distribution or a monodispersed particle size distribution.

  The polymer latex may be a normal polymer latex having a uniform structure or a so-called core / shell type latex. In this case, it may be more preferable that the glass transition temperatures of the core and the shell are different.

  At least one of the polymer latexes in the present invention has a glass transition temperature (Tg) of 70 ° C. or lower. In the present invention, the glass transition temperature of all polymer latexes contained in the receiving layer is preferably 70 ° C. or lower.

  The glass transition temperature is preferably −30 ° C. to 70 ° C., and more preferably 0 ° C. to 70 ° C. Especially, it is preferable that a glass transition temperature is 40 degreeC or more (preferably 40-70 degreeC). When the glass transition temperature is within the above range, the occurrence of cracks can be more effectively suppressed.

  In the present invention, a polymer latex having a glass transition temperature exceeding 70 ° C. can be contained in the receiving layer within a range not impairing the effects of the present invention. The glass transition temperature is preferably −30 ° C. to 130 ° C., more preferably 0 ° C. to 120 ° C. Especially, it is preferable that glass transition temperature is 40 degreeC or more (preferably 40-120 degreeC), and 70 degreeC or more (70-100 degreeC) is more preferable.

Preferred embodiments of the polymer latex in the present invention include acrylic polymers, polyesters, rubbers (for example, SBR resin), polyurethanes, polyvinyl chlorides, polyvinyl acetates, polyvinylidene chlorides, polyolefins, and the like. Any polymer latex can be preferably used.
A crosslinkable polymer latex is also preferably used.

  The polymer latex may be a linear polymer, a branched polymer, a crosslinked polymer, a so-called homopolymer obtained by polymerizing a single monomer, or a copolymer 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.

  The molecular weight of these polymers in the present invention is 5,000 to 1,000,000, preferably 10,000 to 500,000 in terms of number average molecular weight. By being 5000 or more, the mechanical strength of the receiving layer containing the polymer latex can be improved. Moreover, favorable film formability can be obtained by setting it as 1000000 or less.

  There is no restriction | limiting in particular as a monomer used for the synthesis | combination of the polymer latex which can be used for this invention. For example, the following monomer groups (a) to (j) can be suitably exemplified as those that can be polymerized by ordinary radical polymerization or ionic polymerization. These monomers can be selected independently and freely combined to synthesize a polymer latex having the desired performance.

-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) Olefin: 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 acrylates (eg, methyl acrylate, ethyl acrylate, butyl acrylate, cyclohexyl acrylate, 2-ethylhexyl acrylate, dodecyl acrylate, etc.), substituted alkyl acrylates (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, tetrahydrofurfuryl methacrylate Relate, 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, Lenglycol dimethacrylate, 1,4-cyclohexanediacrylate, pentaerythritol tetramethacrylate, pentaerythritol triacrylate, trimethylolpropane triacrylate, trimethylolethane triacrylate, dipentaerythritol pentamethacrylate, pentaerythritol hexaacrylate, 1,2, 4-cyclohexanetetramethacrylate and the like.

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

The polymer latex that can be used in the present invention may be a commercially available one. For example, the following polymer latex can be used.
Examples of acrylic polymers include: Sebian A-4635, 4718, 4601 manufactured by Daicel Chemical Industries, Ltd .; Nipol Lx811, 814, 821, 820, 855 (P-17: Tg 36 ° C.) manufactured by Nippon Zeon Co., Ltd., 857 × 2 (P-18: Tg 43 ° C.); Voncoat R3370 (P-19: Tg 25 ° C.), 4280 (P-20: Tg 15 ° C.) manufactured by Dainippon Ink &Chemicals; Jurimer ET-410 (manufactured by Nippon Pure Chemicals Co., Ltd.) P-21: Tg 44 ° C.); AE116 (P-22: Tg 50 ° C.), AE119 (P-23: Tg 55 ° C.), AE121 (P-24: Tg 58 ° C.), AE125 (P-25: Tg 60) manufactured by JSR Corporation ° C), AE134 (P-26: Tg48 ° C), AE137 (P-27: Tg48 ° C), AE140 (P-28: Tg53 ° C), AE173 (P-29: Tg60 ° C); Aron A-104 (P-30: Tg 45 ° C.); NS-600X, NS-620X manufactured by Takamatsu Yushi Co., Ltd .; Vinibrand 2580, 2583, 2641, 2770, 2770H, 2635, manufactured by Nissin Chemical Industry Co., Ltd. 2886, 5202C, 2706, etc. (all are trade names).

  Examples of polyesters include: FINETEX ES650, 611, 675, 850 manufactured by Dainippon Ink Chemical Co., Ltd .; WD-size, WMS manufactured by Eastman Chemical; A-110, A-115GE, A-manufactured by Takamatsu Yushi Co., Ltd. 120, A-21, A-124GP, A-124S, A-160P, A-210, A-215GE, A-510, A-513E, A-515GE, A-520, A-610, A-613, A-615GE, A-620, WAC-10, WAC-15, WAC-17XC, WAC-20, S-110, S-110EA, S-111SL, S-120, S-140, S-140A, S- 250, S-252G, S-250S, S-320, S-680, DNS-63P, NS-122L, NS-122LX, NS-244LX, NS 140L, NS-141LX, NS-282LX; manufactured by Toagosei Co., Ltd. Aronmelt PES-1000 series, PES-2000 series; manufactured by Toyobo Co., Ltd., MD-1100, MD-1200, MD-1220, MD-1245, MD -1250, MD-1335, MD-1400, MD-1480, MD-1500, MD-1930, MD-1985; Sumitomo Seika Co., Ltd. Sepurgeon ES (all are trade names).

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

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

Examples of polyvinyl chlorides include G351 and G576 manufactured by Nippon Zeon Co., Ltd .; Vinibrand 240, 270, 277, 375, 386 manufactured by Nissin Chemical Industry Co., Ltd., 609, 550, 601, 602, 630, 660, 671, 683, 680, 680S, 681N, 685R, 277, 380, 381, 410, 430, 432, 860, 863, 865, 867, 900, 900GT, 938, 950, etc. (all are trade names).
Examples of polyvinylidene chlorides include L502 and L513 manufactured by Asahi Kasei Kogyo Co., Ltd., D-5071 manufactured by Dainippon Ink and Chemicals, Inc. (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 include Seixsen and Sepouljon G (all are trade names).
Examples of copolymerized nylons include Sephojon 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.
Further, 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.

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

  In the present invention, polyvinyl chlorides are preferable among the above polymer latexes. Among the polyvinyl chlorides, that is, polymer latexes containing at least repeating units obtained from vinyl chloride, polymer latexes containing 50 mol% or more of repeating units obtained from the vinyl chloride are preferable. More preferred is a copolymer latex. As such a copolymer latex, it is preferable that the monomer copolymerized with vinyl chloride is acrylic or methacrylic acid or an ester thereof, vinyl acetate or ethylene. Also preferred are vinyl chlorides and copolymers of acrylic and vinyl acetate. The alcohol portion of the ester portion of the acrylate ester preferably has 1 to 10 carbon atoms, and more preferably has 1 to 8 carbon atoms.

  Examples of such polyvinyl chlorides include those mentioned above, among others, ViniBran 240, ViniBran 270, ViniBran 276, ViniBran 277, ViniBran 375, ViniBran 380, ViniBran 386, ViniBran 410, ViniBran 430, ViniBran 432, VINYBRAN 550, VINYBRAN 601, VINYBRAN 602, VINYBRAN 609, VINYBRAN 619, VINYBRAN 680, VINYBRAN 680S, VINYBRAN 681N, VINYBRAN 683, VINYBRAN 685R, VINYBRAN 690, VINYBRAN 860, VINYBRAN 863, VINYBRAN 685, VINYBRAN 867, VINYBRAN 900, , ViniBran 950 (all are manufactured by Nissin Chemical Industry Co., Ltd.), SE1320, S-830 (all are Sumitomo Chemte Co., Ltd.) is preferable.

The polymer latex used in the present invention is used for receiving a dye migrated from an ink sheet, but any polymer may be used in combination with the polymer latex.
Polymers that can be used in combination may be used to receive the dye, but can also be used as a binder to hold the polymer latex.
Such polymers are preferably transparent or translucent and colorless, and are natural resins, polymers and copolymers, synthetic resins, polymers and copolymers, and other media forming films such as gelatins, polyvinyl alcohols, hydroxys. Ethyl cellulose, cellulose acetate, cellulose acetate butyrate, polyvinyl pyrrolidone, casein, starch, polyacrylic acid, polymethyl methacrylic 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, poly salts Vinylidene, polyepoxides, polycarbonates, polyvinyl acetates, polyolefins, and polyamides and the like. The binder may be coated from water or an organic solvent or emulsion.

  In addition to the polymer latex used for the purpose of receiving the dye migrating from the ink sheet, when used mainly as the binder, the polymer latex has a glass transition temperature (from the viewpoint of processing brittleness and image storage stability). Tg) is preferably in the range of -30 ° C to 70 ° C, more preferably in the range of -10 ° C to 50 ° C, still more preferably in the range of 0 ° C to 40 ° C. It is also possible to use a blend of two or more polymers as the binder, and in this case, it is preferable that the weighted average Tg in consideration of the composition falls within the above range. Moreover, when phase-separating or having a core-shell structure, the weighted average Tg is preferably within the above range.

This glass transition temperature (Tg) can be calculated by the following formula.
1 / Tg = Σ (X _i / Tg _i )
Here, it is assumed that n monomer components from i = 1 to n are copolymerized in the polymer. X _i is the weight fraction of the i-th monomer (ΣX _i = 1), and Tg _i 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 (Tg _i ) of each monomer may be, for example, the value of “Polymer Handbook (3rd Edition)” by Wiley-Interscience, 1989 by J. Brandrup, EHImmergut.

<Water-soluble polymer>
In the present invention, the receptor layer contains at least one water-soluble polymer, and its content (solid content ratio) with respect to the total solid content is 0.01% or more and 3% or less. In the present invention, it is preferably 0.01% or more and 1% or less. When the content of the water-soluble polymer is less than 0.01%, the strength of the receiving layer is insufficient. If it exceeds 3%, the transfer density during printing tends to decrease.

  Here, the water-soluble polymer means a polymer that dissolves 0.05 g or more with respect to 100 g of water at 20 ° C. The solubility of the water-soluble polymer is more preferably 0.1 g or more, further preferably 0.5 g or more, and particularly preferably 1 g or more with respect to 100 g of water at 20 ° C. The polymer latex is one in which polymer fine particles are dispersed in a dispersion medium, and is different from the water-soluble polymer in the present invention.

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). For example, 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.
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.
Plant polysaccharides include gum arabic, κ-carrageenan, ι-carrageenan, λ-carrageenan, guar gum (Squalon Supercol, etc.), locust bean gum, pectin, tragacanth, corn starch (National Starch & Chemical Co. Purity) -21), phosphorylated starch (such as National Starch & Chemical Co. made by National 78-1898), and other microbial polysaccharides such as xanthan gum (such as Kelco Keltrol T) and dextrin (made by National Starch & Chemical Co.) Nadex360, etc.) (all are trade names).

  Examples of animal natural polymers include gelatin (such as Crodyne B419 manufactured by Croda), casein, and sodium chondroitin sulfate (such as Cromoist CS manufactured by Croda) (all are trade names). Cellulose systems include ethyl cellulose (such as Cellofas WLD manufactured by ICI), carboxymethyl cellulose (such as CMC manufactured by Daicel Chemical Industries), hydroxyethyl cellulose (such as HEC manufactured by Daicel Chemical Industries), hydroxypropyl cellulose (such as Klucel manufactured by Aqualon), Examples include methylcellulose (such as Viscontran from Henkel), nitrocellulose (such as Isopropyl Wet from Hercules), and cationized cellulose (such as Crodacel QM from Croda) (all are trade names).

  As starch, phosphorylated starch (National 78-1898 from National Starch & Chemical Co., Ltd.), as alginic acid, sodium alginate (Keltone from Kelco, etc.), propylene glycol alginate, and other categories, cationized guar gum (Such as Hi-care 1000 manufactured by Alcolac) and sodium hyaluronate (such as Hyalure manufactured by Lifecare Biomedial).

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.

  Next, among 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.

Among the water-soluble synthetic polymers that can be used in the present invention, polyvinyl alcohols are particularly preferable.
Hereinafter, polyvinyl alcohol will be described in more detail.
As a completely 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 mass%, viscosity (4 mass%, 20 ° C.) 39.5 ± 4.5 CPS], PVA-124 [PVA content 94.0 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% by mass, saponification degree 97.5 ± 0.5 mol%, sodium acetate content 1.0% by 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 quality %, 20 ℃) 25.0 ± 3.5CPS] (above all are manufactured by Kuraray Co., trade name of), and the like.

  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 mass%, saponification degree 88.0 ± 1.0 mol%, sodium acetate content 1.0 mass%, volatile content 5. 0 mass%, viscosity (4 mass%, 20 ° C.) 22.5 ± 2.0 CPS], PVA-220 [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.) 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 mass%, saponification degree 88.0 ± 1.5 mol%, sodium acetate content 1.0 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% by mass, saponification degree 88.0 ± 1.0 mol%, sodium acetate content 1.0% by 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, saponification degree 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 of which are trade names of Kuraray Co., Ltd.).

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

  Examples of the modified polyvinyl alcohol include those described in Koichi Nagano et al., “Poval” (published by Kobunshi Shuppankai). Examples of the modification method of polyvinyl alcohol include modification with a cation, an anion, an —SH compound, an alkylthio compound, and 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 with a trace amount of solvent or inorganic salt added to the aqueous solution. Specifically, the additives described in the above-mentioned document, Koichi Nagano et al., “Poval”, published by Kobunshi Shuppankai, pages 144 to 154 can be used. A typical example is boric acid. By containing boric acid, the coating surface quality can be improved, which is preferable. The addition amount of boric acid is preferably 0.01 to 40% by mass with respect to polyvinyl alcohol.

  In the present invention, the water-soluble polymer is preferably polyvinyl alcohols and / or gelatin, and gelatin is particularly preferable.

  Polymers other than the water-soluble polymer used as a binder in the present invention can be easily obtained by solution polymerization, suspension polymerization, emulsion polymerization, dispersion polymerization, anionic polymerization, cationic polymerization, etc. Most preferred are latexes obtained by law. An aqueous dispersion obtained by a method of preparing a polymer in a solution and neutralizing or adding an emulsifier followed by water and forcibly stirring is also preferred.

  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. For example, edited by Taira Okuda, Hiroshi Inagaki, “Synthetic Resin Emulsion”, published by Kobunshi Publishing (1978); Takaaki Sugimura, Masao Kataoka, Junichi Suzuki, Keiji Kasahara, “Application of Synthetic Latex”, published by Kobunshi Publishing (1993); 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 a radical generating ability, such as inorganic peroxides such as persulfate and hydrogen peroxide, and peroxides described in Nippon Oil & Fats Co., Ltd. “Organic Peroxide Catalog”, etc. The azo compounds described in Yaku Kogyo Co., Ltd. “Azo Polymerization Initiator Catalog” can be used. Among them, water-soluble peroxides such as persulfate and water-soluble azo compounds described in Wako Pure Chemical Industries, Ltd., `` Azo polymerization initiator catalog '' and the like 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, ammonium persulfate, sodium persulfate, potassium persulfate, etc. Peroxides are preferred from the viewpoints of image storage stability, 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 ensured in a small amount and resistance to hydrolysis, and a length represented by Perex SS-H (trade name, manufactured by Kao Corporation). A chain alkyl diphenyl ether disulfonate is more preferable, and a low electrolyte type such as Pionine A-43-S (trade name, manufactured by 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.

  It is preferable to use a chelating agent for the synthesis of the polymer latex used in the present invention. 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 each publication 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), polyphenol-based chelating agents, polyamine-based compounds Chelate compounds Properly, 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′-bis (2-hydroxybenzyl) ethylenediamine-N, N′-diacetic acid, ethylenediamine-N, N′-diacetic acid-N, N′-diacethydroxamic acid, N-hydroxyethylethylenediamine-N , N ′, N′-triacetic acid, ethylenediamine-N, N, N ′, N′-tetraacetic acid, 1,2-propylenediamine-N, N, N ′ , N′-tetraacetic acid, d, l-2,3-diaminobutane-N, N, N ′, N′-tetraacetic acid, meso-2,3-diaminobutane-N, N, N ′, N′- Tetraacetic acid, 1-phenylethylenediamine-N, N, N ′, N′-tetraacetic acid, d, l-1,2-diphenylethylenediamine-N, N, N ′, N′-tetraacetic acid, 1,4-diamino Butane-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'-tetraacetic acid, cyclohexane-1,4-diamine-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, trie Lentetamine-N, N, N ′, N ″, N ′ ″, N ′ ″-hexaacetic acid, 1,2,3-triaminopropane-N, N, N ′, N ″, N ′ Examples include '', N '' '-hexaacetic acid, and those in which some of the carboxyl groups of these compounds are substituted with alkali metal salts such as sodium and potassium, and ammonium salts.

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

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

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

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

  In the polymer latex used in the present invention, an aqueous solvent can be used as a solvent in the coating solution, but a water-miscible organic solvent may be used in combination. Examples of the water-miscible organic solvent include alcohols such as methyl alcohol, ethyl alcohol and propyl alcohol, cellosolves such as methyl cellosolve, ethyl cellosolve and butyl cellosolve, ethyl acetate and dimethylformamide. The amount of these organic solvents added is preferably 40% or less, more preferably 30% or less of the solvent.

The polymer latex used in the present invention preferably has a polymer concentration of 10 to 70% by mass, more preferably 20 to 60% by mass, and particularly preferably 30 to 55% by mass with respect to the latex liquid.
The addition amount of the polymer latex is preferably 50 to 95% by mass, more preferably 70 to 90% by mass, based on the total polymer content in the receptor layer.
In addition, the polymer latex in the heat-sensitive transfer image-receiving sheet in the present invention includes a gel or dry film state formed by drying a part of the solvent after coating.

  The binder for the receiving layer in the present invention is preferably at least one selected from polyurethanes, styrene-butadiene copolymers, polyvinyl alcohol and gelatin, more preferably polyvinyl alcohol and / or gelatin, most preferably gelatin. .

<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 is preferably a polymer having a high molecular weight. The weight average molecular weight of the high molecular weight ultraviolet absorber is preferably 10,000 or more, and more preferably 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 applying a coating film of an aqueous dispersion system by forming a latex, thereby reducing the manufacturing cost. 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 addition amount of the polymer grafted with the ultraviolet absorber or the latex thereof is preferably 5 to 50 parts by weight, and 10 to 30 parts by weight with respect to the dyeable receiving polymer latex used for receiving the dye forming the receiving layer. Is more preferable.

<Release agent>
In addition, a release agent may be added to the receiving layer in order to prevent thermal fusion with the thermal transfer sheet during image formation. As the release agent, silicone oil and phosphoric ester plasticizer fluorine compound can be used, and silicone oil is particularly preferably used. As the silicone oil, modified silicone oils such as epoxy modification, alkyl modification, amino modification, carboxyl modification, alcohol modification, fluorine modification, alkylaralkyl polyether modification, epoxy / polyether modification, polyether modification, etc. are preferably used. The reaction product of vinyl modified silicone oil and hydrogen modified silicone oil is good. The addition amount of the release agent is preferably 0.2 to 30 parts by mass with respect to the receiving polymer.
The lubricant described in the emulsion section below is almost synonymous with the same effect as the release agent described here. In this invention, what was used as a dispersion for convenience was made into the mold release agent demonstrated here as a lubricant emulsion and the other thing.

<Emulsions>
Hydrophobic additives such as lubricants and antioxidants can be obtained by a known method such as the method described in U.S. Pat. No. 2,322,027 (for example, receiving layer, heat insulating layer, subbing 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, and 4,555,476 No. 4,599,296, JP-B-3-62256, etc., or a high boiling point organic solvent described in the specification, etc., if necessary, a low boiling point organic solvent having a boiling point of 50 ° C. to 160 ° C. It can be used in combination. These lubricants, antioxidants, high-boiling organic solvents and the like can be used in combination of two or more.

  Examples of the lubricant include solid waxes such as polyethylene wax, amide wax, 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. Silicone compounds such as various waxes, fluorine compounds represented by fluorine surfactants, silicone surfactants, silicone oils and / or cured products thereof are preferably used.

<Matting agent>
In the present invention, it is preferable to add a matting agent for imparting releasability. The matting agent is preferably contained in the outermost surface layer, the layer functioning as the outermost surface layer of the heat-sensitive transfer image-receiving sheet, or a layer close to the outer surface. The outermost surface layer can be made into two layers as required. Most preferably, it is added to the outermost receiving layer. The matting agent can be added to both the outermost layer on the image forming layer surface and the outermost layer on the back surface, and can also be added to both layers. In particular, it is preferable to include a matting agent on the side of the support containing the slip agent.

  The matting agent is preferably dispersed in advance with a binder or the like and used as a matting agent particle dispersion.

  Examples of the matting agent generally include fine particles of an organic compound insoluble in water and fine particles of an inorganic compound. In the present invention, fine particles containing an organic compound are preferable from the viewpoint of dispersibility. As long as it contains an organic compound, it may be an organic compound fine particle composed of an organic compound alone, or an organic / inorganic composite fine particle containing not only an organic compound but also an inorganic compound. Examples of the matting agent include, for example, U.S. Pat. Nos. 1,939,213, 2,701,245, 2,322,037, 3,262,782, 3,539,344, Those known in the silver salt sensitive material industry such as the organic matting agent described in each specification such as 3,767,448 can be used.

Since the temperature of the receiving layer surface becomes high during image printing, the matting agent preferably has heat resistance.
In particular, a polymer having a thermal decomposition temperature of 200 ° C. or higher is preferable. More preferably, it is a polymer having a thermal decomposition temperature of 240 ° C. or higher. In addition, when the image is printed, not only heat but also pressure is applied to the surface of the receiving layer.

  The matting agent contained in the outermost layer on the image forming layer side and the outermost layer adjacent layer is dispersed in advance with a binder and used as a matting agent particle dispersion. The dispersion method is (a) a matting agent. The dispersion of the matting agent by removing the low boiling point organic solvent from the emulsion by emulsifying and dispersing the polymer to be dissolved in an aqueous medium as a solution (for example, dissolved in a low boiling point organic solvent) to obtain polymer droplets There are two methods: (b) a method in which fine particles such as a polymer to be a matting agent are prepared in advance, and a dispersion is prepared so as not to cause lumps in an aqueous medium. In the present invention, in consideration of the environment, the method (b) in which a low-boiling organic solvent is not discharged to the environment is preferable.

  Since the dispersion state of the mat particle dispersion in the present invention is stabilized when it contains a surfactant, it is preferable to add a surfactant.

<Surfactant>
In the heat-sensitive transfer image-receiving sheet of the present invention, a surfactant can be contained in the above arbitrary layer. Among these, it is preferable to make it contain in a receiving layer and an intermediate | middle layer.
The addition amount of the surfactant is preferably 0.01 to 5% by mass, more preferably 0.01 to 1% by mass, and 0.02 to 0.2% by mass with respect to the total solid content. It is particularly preferred that

Various surfactants such as anionic, nonionic, and cationic surfactants are known. As the surfactant that can be used in the present invention, known ones can be used. For example, those introduced in “Supervision of Functional Surfactant / Mitsuo Tsunoda, Issued / August 2000, Chapter 6” Among them, an anionic fluorine-containing surfactant is preferable.
Application is possible even when no surfactant is contained, but since the surface tension of the application liquid is high, the application surface may be uneven and uneven. By containing a surfactant in the coating solution, the surface tension can be lowered, unevenness during coating can be eliminated, the coated surface can be made uniform, and coating can be performed stably.

  Although the specific example of a fluorine compound is illustrated below, the fluorine compound which can be used by this invention is not restrict | limited at all by the following specific examples. Unless otherwise specified, the alkyl group and perfluoroalkyl group in the structure notation of the following exemplified compounds means a group having a linear structure.

  These fluorine compounds are used as a surfactant in a coating composition for forming a layer constituting a heat-sensitive transfer image-receiving sheet (in particular, a receiving layer, a heat insulating layer, a protective layer, an undercoat layer, a back layer, etc.). However, in the present invention, it can be preferably contained in the receiving layer and the intermediate layer.

<Preservative>
When a coating solution, a thermal transfer image-receiving sheet, a print image, and the like are stored, microorganisms (particularly bacteria, mold, yeast, etc.) adhere to these materials during storage, and their performance is often lowered. In order to prevent this, a preservative can be contained in a range that does not affect other performances.
The preservative referred to in the present invention is a compound used to suppress the compound used in the thermal transfer image-receiving sheet from undergoing a decomposition reaction due to the growth of the microorganism, and the definition and specific compound by the general formula are: Antiseptic and antibacterial handbook, published by Gihodo Publishing (1986), Hiroshi Horiguchi, antibacterial and antifungal chemistry, Sankyo Publishing (1986), antibacterial and antifungal encyclopedia, published by the Japanese Society for Antibacterial and Antifungal (1986) Yes.

  The preservative contained in the heat-sensitive transfer image-receiving sheet in the present invention is not particularly limited, but phenol or derivatives thereof, formalin, imidazole derivatives, sodium dehydroacetate, 4-isothiazolin-3-one derivatives, benzoisothiazoline-3-one , Benzotriazole derivatives, amiding anidine derivatives, quaternary ammonium salts, derivatives of pyrozine, quinoline, guanidine, diazine, triazole derivatives, oxazole, oxazine derivatives, 2-mercaptopyridine-N-oxide or salts thereof, formaldehyde donor antibacterial agents Etc. Among these, phenol or a derivative thereof, 4-isothiazolin-3-one derivative, benzisothiazolin-3-one, and the like are preferable.

  Besides these, compounds represented by any one of the following general formulas (I) to (IV) can be used as preservatives.

In general formula (I), R ¹ and R ² may be the same or different and each represents a hydrogen atom, a hydroxy group, or a lower alkyl group. X ¹ is a hydrogen atom, a halogen atom, a nitro group, a cyano group, an aryl group, a lower alkyl group, a lower alkenyl group, an aralkyl group, an alkoxy group, —COR ³ , —SO ₂ R ⁴ , or —N (R ⁵ ) R. ⁶ , R ³ and R ^{4 each} represent a hydrogen atom, —OM, a lower alkyl group, a lower alkoxy group, or —N (R ⁷ ) R ⁸ .
R ⁵ and R ⁶ may be the same or different and each represents a hydrogen atom, a lower alkyl group, —COR ⁹ , or —SO ₂ R ¹⁰ . R ⁹ and R ¹⁰ represent a lower alkyl group or —N (R ¹¹ ) R ¹² , and R ⁷ , R ⁸ , R ¹¹ , and R ¹² may be the same or different, and may be a hydrogen atom or a lower alkyl group. Represents.
M represents a hydrogen atom, an alkali metal atom, or an atomic group necessary to form a monovalent cation, l represents an integer of 2 to 6, m represents an integer of 1 to 4, and n represents 6- represents an integer of m. However, when there are a plurality of R ¹ , R ² and X ^1, each may be different from each other.

In the general formula ^{(II), R 13} is a hydrogen atom, an alkyl group, an alkenyl group, an aralkyl group, an aryl group, a heterocyclic group, a group represented by the following general formula (II-1) or Formula (II-2) R ¹⁴ and R ¹⁵ each represent a hydrogen atom, an alkyl group, an aryl group, a cyano group, a heterocyclic group, an alkylthio group, an alkylsulfoxy group, or an alkylsulfonyl group, and R ¹⁴ and R ¹⁵ are bonded to each other. An aromatic ring may be formed.

R ¹⁶ and R ¹⁷ each represent a hydrogen atom, an alkyl group, an aryl group, or an aralkyl group.

Among these, those in which R ¹⁴ and R ¹⁵ are hydrogen atoms and R ¹³ is a methyl group (hereinafter may be referred to as compound II-a) are preferable. Further, R ¹⁴ and R ¹⁵ are bonded to each other to form an aromatic ring, and a combination of the compound II-a with R ¹³ being a hydrogen atom, R ¹⁴ is a chlorine atom, R ¹⁵ is a hydrogen atom, R ¹³ The combination of a compound in which is a methyl group and compound II-a is more preferred.

In the general formula (III), R ¹⁸ represents a hydrogen atom, an alkyl group or a hydroxymethyl group, and R ¹⁹ represents a hydrogen atom or an alkyl group.

In general formula (IV), R ²⁰ represents a lower alkylene group, X ² represents a hydrogen atom, a halogen atom, a nitro group, a hydroxy group, a cyano group, a lower alkyl group, a lower alkoxy group, —COR ²¹ , —N (R ²² ) represents R ²³ , —SO ₃ M, R ²¹ represents a hydrogen atom, —OM, lower alkyl group, aryl group, aralkyl group, lower alkoxy group, aryloxy group, aralkyloxy group, —N (R ²⁴ ) R ²⁵ .
R ²² and R ²³ each represent a hydrogen atom, a lower alkyl group, an aryl group, an aralkyl group, —COR ²⁶ , or —SO ₂ R ^{26, and} may be the same or different from each other, and R ²⁴ , R ²⁵ Each represents a hydrogen atom, a lower alkyl group, an aryl group or an aralkyl group, and may be the same or different from each other, R ²⁶ represents a lower alkyl group, an aryl group or an aralkyl group, M represents a hydrogen atom, An atomic group necessary for forming an alkali metal atom and a monovalent cation is represented, p represents 0 or 1, and q represents 0 or an integer from 1 to 5.

  One preservative may be used alone, or two or more arbitrary compounds may be selected and used in combination. The preservative may be added as it is, but it may be dissolved in water or an organic solvent such as methanol, ethanol, isopropyl alcohol, acetone, ethylene, or ethylene glycol, and added as a solution to the image-receiving sheet coating solution. Or you may add in latex. Alternatively, it may be dissolved in a high boiling point solvent, a low boiling point solvent, or a mixed solvent of both, and then emulsified and dispersed in the presence of a surfactant and added to the latex.

  In the present invention, at least one receiving layer is applied with an aqueous coating solution. When a plurality of receiving layers are provided, all of these receiving layers should be prepared by applying an aqueous coating solution and then drying. Is preferred. However, “aqueous” as used herein means that 60% by mass or more of the solvent (dispersion medium) of the coating solution is water. Components other than water in the coating solution include methyl alcohol, ethyl alcohol, isopropyl alcohol, methyl cellosolve, ethyl cellosolve, dimethylformamide, ethyl acetate, diacetone alcohol, furfuryl alcohol, benzyl alcohol, diethylene glycol monoethyl ether, oxyethyl phenyl ether A water miscible organic solvent such as can be used.

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

(Insulation layer)
The heat-sensitive transfer image-receiving sheet in the present invention has at least one heat insulating layer. The heat insulating layer (porous layer) serves to protect the support from heat during heat transfer using a thermal head. Moreover, since it has high cushioning properties, a thermal transfer image-receiving sheet with high printing sensitivity can be obtained even when paper is used as the support.

In the heat-sensitive transfer image-receiving sheet of the present invention, the heat insulating layer contains at least one hollow polymer. Thereby, the heat insulation of a heat insulation layer becomes more favorable.
The hollow polymer in the present invention is a polymer particle having independent pores inside the particle, preferably a polymer latex. For example, 1) Non-foaming in which water is contained in the partition formed by polystyrene, acrylic resin, styrene-acrylic resin, etc., and after coating and drying, the water in the particles evaporates out of the particles and the inside of the particles becomes hollow Hollow polymer particles of type 2) Low-boiling liquids such as butane and pentane are covered with a resin made of polyvinylidene chloride, polyacrylonitrile, polyacrylic acid, polyacrylic acid ester, or a mixture or polymer thereof. Examples include foamed microballoons in which the interior of the particles becomes hollow when the low-boiling liquid inside the particles expands by heating after coating, and 3) microballoons obtained by heating and foaming the above 2) in advance to form a hollow polymer. .

The average particle diameter of these hollow polymers is preferably 0.1 to 20 μm, more preferably 0.1 to 5.0 μm, further preferably 0.2 to 3.0 μm, and It is especially preferable that it is 3-1.0 micrometer.
When the average particle size is 0.1 μm or more, a decrease in the hollow ratio can be suppressed and desired heat insulation can be obtained. Moreover, it can suppress that planar failure other than the coarse particle of a heat insulation layer generate | occur | produces that it is 5.0 micrometers or less.

The hollow polymer preferably has a hollow ratio of about 20 to 70%, particularly preferably 20 to 50%. Desired heat insulation is obtained by setting the hollow ratio to 20% or more. Further, when the ratio is 70% or less, an increase in the ratio of easily broken hollow polymer particles and incomplete hollow polymer particles can be suppressed, and generation of printing defects can be suppressed and film strength can be improved.
In the present invention, two or more kinds of hollow polymers can be mixed and used as necessary.

  Examples of the hollow polymer that can be used in the present invention include, as specific examples of the above 1), Ropaque 1055 manufactured by Law and Haas, Boncoat PP-1000 manufactured by Dainippon Ink, SX866 (B) manufactured by JSR, and ZEON NIPPOL MH5055 (all are trade names) etc. are mentioned. Specific examples of 2) include F-30 and F-50 (both trade names) manufactured by Matsumoto Yushi Seiyaku Co., Ltd. Specific examples of the above 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. The hollow polymer used for the heat insulating layer may be made into a latex.

  The glass transition temperature of the hollow polymer in the present invention is preferably 10 ° C. or higher than the glass transition temperature of the polymer latex. Since the glass transition temperature is high, hollow polymer particles having a sufficient porosity after the coating / drying step can be obtained. More specifically, a hollow polymer having a glass transition temperature of 90 ° C. or higher is preferable, and a glass polymer having a glass transition temperature of 110 ° C. or higher (preferably 200 ° C. or lower) is particularly preferable.

  The hollow polymer used in the present invention is particularly preferably non-foamed hollow polymer particles having a glass transition temperature of 110 ° C. or higher (preferably 200 ° C. or lower).

Here, the relationship between the glass transition temperature (Tg ₂ ) of at least one hollow polymer and the glass transition temperature (Tg ₁ ) of the polymer latex for receiving at least one dye in the receiving layer is expressed as Tg ₁ +10 The case of ≦ Tg ₂ is preferable from the viewpoint of the effect of the present invention.

  The heat insulating layer containing the hollow polymer preferably contains a water-dispersed resin or a water-soluble resin as a binder resin in addition to the hollow polymer. 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 a butadiene copolymer, a urethane resin, a polyvinylidene chloride resin, a cellulose derivative, casein, starch, and gelatin can be used. These are preferably water-soluble polymers described in the receiving layer. Among these binder resins, at least one selected from gelatin, polyvinyl alcohol, styrene-butadiene copolymer and urethane resin is preferable, and gelatin and polyvinyl alcohol are more preferable. These resins can be used alone or in admixture of two or more.

  The solid content of the hollow polymer in the heat insulating layer is preferably between 5 and 2000 parts by mass when the solids content of the binder resin is 100 parts by mass. Moreover, 1-70 mass% is preferable with respect to the total solid, and, as for content of the hollow polymer in a heat insulation layer, 10-40 mass% is more preferable. Sufficient heat insulation can be obtained by containing 1 mass% or more. Moreover, by setting it as 70 mass% or less, the fall of the binding force of hollow polymers can be suppressed, and it can suppress that problems, such as powder fall or film peeling, generate | occur | produce during a process.

As content with respect to the total solid of the said binder resin in a heat insulation layer, 0.5-14 mass% is preferable, and 1-6 mass% is especially preferable. 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 thickness of the heat insulation layer containing a hollow polymer is 5-50 micrometers, and it is more preferable that it is 5-40 micrometers.

(Middle layer)
At least one intermediate layer may be formed between the support and the heat insulating layer. Specific examples of the intermediate layer include a white background adjustment layer, a charge adjustment layer, an adhesive layer, a primer layer, and an undercoat layer. About these layers, it can be set as the structure similar to what was described, for example in patent 3585599 specification, patent 2925244 specification. It is also possible to form a desired function by forming at least one intermediate layer between the heat insulating layer and the receiving layer.

(Support)
In the present invention, it is preferable to use a water-resistant support 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. Examples of the water resistant support include coated paper and laminated paper. Of these, laminated paper is preferable in terms of surface smoothness. Similar to polyethylene laminated paper (sometimes abbreviated as WP paper) used for photographic paper in the field of silver salt photography, that is, a support mainly composed of cellulose and coated with at least a receiving layer A support having a surface to be coated with a polyolefin resin can be suitably used.

-Coated paper-
The coated paper is paper in which various resins, rubber latex, or polymer materials are coated on one side or both sides of a base paper or the like. The coated amount of the coated paper can be changed 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 one side or both sides 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, polyacrylic acid ester resin or polymethacrylic acid ester resin (for example, polymethyl methacrylate, polybutyl methacrylate, polymethyl acrylate, polybutyl acrylate, etc.) obtained by condensation of polycarbonate, polycarbonate resin, polyvinyl acetate resin, styrene acrylate Examples thereof include resins, styrene-methacrylic acid ester copolymer resins, and vinyl toluene acrylate resins.
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, polymer sheets or films on one side or both sides of 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 viewpoints of cost, suitability for lamination, and the like.

  The blend of the said high density polyethylene and the said low density polyethylene is used by the blend ratio (mass ratio) 1/9-9/1, for example. 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. Among them, those having extrudability are 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. This is generally used as a support for photographic paper in the field of silver salt photography.

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 of the support. As a support for a thermal transfer image-receiving sheet of photographic quality, a support for color silver salt photographic paper is used. Close ones 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.

  In the present invention, the plurality of layers are composed mainly of a resin. The main component of the resin for forming each layer is preferably a polymer 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 polymer latex is 5 μm or less, and particularly preferably 1 μm or less. The polymer latex may contain a known additive such as a surfactant, a dispersant, and a binder resin as necessary.

  EXAMPLES The present invention will be specifically described below with reference to examples, but the present invention is not limited to these examples. Unless otherwise specified, “part” and “%” are based on mass.

<Example 1>
[Create 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 Polyvinyl butyral resin 4.5 parts (Esrec BX-1, trade name, manufactured by Sekisui Chemical Co., Ltd.)
90 parts of methyl ethyl ketone / toluene (mass ratio 1/1)

-Magenta composition-
Magenta dye (Disperse Red 60) 5.5 parts Polyvinyl butyral resin 4.5 parts (ESREC BX-1, trade name, manufactured by Sekisui Chemical Co., Ltd.)
90 parts of methyl ethyl ketone / toluene (mass ratio 1/1)

-Cyan composition-
Cyan dye (Solvent Blue 63) 5.5 parts Polyvinyl butyral resin 4.5 parts (S-REC BX-1, trade name, manufactured by Sekisui Chemical Co., Ltd.)
90 parts of methyl ethyl ketone / toluene (mass ratio 1/1)

[Preparation of thermal transfer image-receiving sheet]
(Support)
A corona discharge treatment was applied to the paper support surface laminated on both sides with polyethylene to prepare a support.

(Thermal transfer image-receiving sheet)
On the support prepared as described above, an image receiving sheet having the constitution of the undercoat layer 1, the undercoat layer 2, the heat insulating layer, and the receiving layer was prepared in order from the lower layer. The composition of the coating solution and the coating amount are shown below.
The coating is performed by slide coating, after passing through a set zone of 6 ° C. for 30 seconds to eliminate the fluidity of the liquid, it is dried by spraying a drying air of 22 ° C. and 45% RH on the coating surface for 2 minutes. went.

-Coating liquid for forming undercoat layer 1-
(composition)
An aqueous solution obtained by adding 1% sodium dodecylbenzenesulfonate to a 3% gelatin aqueous solution.
The pH was adjusted to 8 with NaOH.
(Application amount) 11 ml / m ²

-Coating liquid for forming undercoat layer 2-
(composition)
60 parts of styrene butadiene latex (SR103 manufactured by Nippon A & L Co., Ltd.)
Polyvinyl alcohol (PVA) 6% aqueous solution 40 parts Surfactant 1% aqueous solution (BFS-1 below) 2 parts The pH was adjusted to 8 with NaOH.
(Application amount) 11 ml / m ²

-Coating solution for heat insulation layer formation-
(Preparation of Emulsion A)
Emulsion A was prepared by the following procedure. The following compound EB-9 was dissolved in 42 g of a high boiling point solvent (Solv-5 below) and 20 ml of ethyl acetate. This solution was emulsified and dispersed in 250 g of a 20% by weight gelatin aqueous solution containing 1 g of sodium dodecylbenzenesulfonate by a high-speed stirring emulsifier (dissolver), and water was added to prepare 380 g of Emulsion A.
Here, the amount of Compound EB-9 added was 30 mmol in Emulsion A.
However, in the actual experiment, the production scale was changed according to the required amount. At this time, the ratio of each additive and each solvent was set to be the same as described above.

(Coating solution composition for heat insulation layer formation)
Emulsion A prepared earlier 21 parts Hollow polymer 48 parts (manufactured by Nippon Zeon Co., Ltd. MH5055)
10% aqueous gelatin solution 28 parts Water 3 parts Preservative (compound represented by the following formula PR-1) 0.2 parts The pH was adjusted to 8 with NaOH.
(Application amount) 50 ml / m ²

-Coating liquid for receiving layer formation-
(Preparation of emulsion B)
High-boiling solvent (Solv-5) 11.0 g, KF-96 (dimethyl silicone manufactured by Shin-Etsu Chemical Co., Ltd.) 9 g, the above compound EB-9 15.5 g, KAYARAD DPCA-30 (manufactured by Nippon Kayaku Co., Ltd.) 7 0.5 g and 20 ml of ethyl acetate were mixed and dissolved. This solution was emulsified and dispersed in 250 g of a 20% by weight gelatin aqueous solution containing 1 g of sodium dodecylbenzenesulfonate with a high-speed stirring emulsifier (dissolver), and water was added to prepare 380 g of Emulsion B.
However, in the actual experiment, the production scale was changed according to the required amount. At this time, the ratio of each additive and each solvent was set to be the same as described above.

(Receiving layer forming coating solution X)
Emulsion B prepared previously 4 parts by mass Vinyl chloride polymer latex 53 parts by mass (Nishin Chemical Co., Ltd., Vinibrand 901 Tg60 ° C)
10 parts by weight of vinyl chloride polymer latex (Nishin Chemical Co., Ltd. BiniBran 276 Tg33 ° C)
6 parts by weight of microcrystalline wax (EMUSTAR-42X manufactured by Nippon Wax Co., Ltd.)
Water 22 parts by weight Surfactant 1% aqueous solution (BFS-1 above) 4 parts by weight Matting agent 1 part by weight (Melamine-silica resin specific gravity 1.65 (Optobeads 3500M manufactured by Nissan Chemical Industries, Ltd.))
Preservative (compound represented by PR-1 above) 0.1 part by mass

  The above composition was mixed to prepare a receiving layer forming coating solution X.

(Receiving layer forming coating solution 1)
An emulsion B1 was prepared by replacing the 20% by weight gelatin aqueous solution in the preparation of the emulsion dispersion B with water, and the emulsion B1 was used in place of the emulsion B. A coating solution 1 for forming a receiving layer was prepared.

(Receiving layer forming coating solution 2)
An emulsion B2 was prepared by replacing the 20 mass% gelatin aqueous solution in the preparation of the emulsion dispersion B with a 4 mass% gelatin aqueous solution, and the emulsion B2 was used in place of the emulsion B. In the same manner as described above, a coating solution 2 for forming a receiving layer was prepared.

(Receiving layer forming coating solution 3)
The receiving layer forming coating solution X was designated as receiving layer forming coating solution 3.

(Receiving layer forming coating solution 4)
Further, 2.0 parts by mass of a 20% by weight gelatin aqueous solution was added to the receiving layer coating solution X to prepare a coating solution 4 for forming an image receiving layer.

(Receptive layer forming coating solution 5)
6.7 parts by mass of a 20% by weight aqueous gelatin solution was further added to the receiving layer forming coating solution X to prepare an image receiving layer forming coating solution 5.

(Receptive layer forming coating solution 6)
An image receiving layer forming coating solution 6 was prepared by further adding 11.3 parts by weight of a 20% by weight aqueous gelatin solution to the receiving layer forming coating solution X.

(Receiving layer forming coating solution 7)
An image receiving layer forming coating solution 7 was prepared by further adding 15.0 parts by weight of a 20% by weight gelatin aqueous solution to the receiving layer forming coating solution X.

(Receiving layer forming coating solution 8)
In the preparation of the coating solution 1 for forming the receiving layer, instead of vinyl chloride polymer latex (Vinibran 901 Tg 60 ° C. manufactured by Nissin Chemical Co., Ltd.), vinyl chloride polymer latex (Vinibran 900 Tg 73 manufactured by Nissin Chemical Co., Ltd.) was used. The receiving layer forming coating solution 8 was prepared in the same manner as in the receiving layer forming coating solution 1 except that [° C.] was used.

(Receiving layer forming coating solution 9)
In preparation of the coating solution 2 for forming the receiving layer, instead of vinyl chloride polymer latex (Vinibran 901 Tg 60 ° C. manufactured by Nissin Chemical Co., Ltd.), vinyl chloride polymer latex (Vinibran 900 Tg 73 manufactured by Nissin Chemical Co., Ltd.) was used. The receiving layer-forming coating solution 9 was prepared in the same manner as the receiving layer-forming coating solution 2 except that (° C.) was used.

(Receiving layer forming coating solution 10)
In the preparation of the coating solution 3 for forming the receiving layer, a vinyl chloride polymer latex (Vinibran 900 Tg73, manufactured by Nissin Chemical Co., Ltd.) was used instead of the vinyl chloride polymer latex (Vinibran 901 Tg, 60 ° C. manufactured by Nissin Chemical Co., Ltd.). The receiving layer-forming coating solution 10 was prepared in the same manner as the receiving layer-forming coating solution 3 except that (° C.) was used.

(Receiving layer forming coating solution 11)
In the preparation of the coating solution 4 for forming the receiving layer, instead of vinyl chloride polymer latex (Vinibran 901 Tg 60 ° C. manufactured by Nissin Chemical Co., Ltd.), vinyl chloride polymer latex (Vinibran 900 Tg 73 manufactured by Nissin Chemical Co., Ltd.) was used. The receiving layer-forming coating solution 11 was prepared in the same manner as the receiving layer-forming coating solution 4 except that (° C.) was used.

(Receiving layer forming coating solution 12)
In the preparation of the coating solution 5 for forming the receiving layer, instead of vinyl chloride polymer latex (Vinibran 901 Tg 60 ° C. manufactured by Nissin Chemical Co., Ltd.), vinyl chloride polymer latex (Vinibran 900 Tg 73 manufactured by Nissin Chemical Co., Ltd.) was used. The receiving layer forming coating solution 12 was prepared in the same manner as in the receiving layer forming coating solution 5 except that (° C.) was used.

(Receiving layer forming coating solution 13)
In the preparation of the coating solution 6 for forming the receiving layer, instead of vinyl chloride polymer latex (Vinibran 901 Tg 60 ° C., manufactured by Nissin Chemical Co., Ltd.), vinyl chloride polymer latex (Vinibran 900 Tg73, manufactured by Nissin Chemical Co., Ltd.) was used. The receiving layer-forming coating solution 13 was prepared in the same manner as the receiving layer-forming coating solution 6 except that (° C.) was used.

(Receiving layer forming coating solution 14)
In the preparation of the coating solution 7 for forming the receiving layer, instead of vinyl chloride polymer latex (Vinibran 901 Tg 60 ° C. manufactured by Nissin Chemical Co., Ltd.), vinyl chloride polymer latex (Vinibran 900 Tg 73 manufactured by Nisshin Chemical Co., Ltd.) was used. The receiving layer forming coating solution 14 was prepared in the same manner as the receiving layer forming coating solution 7 except that the temperature was 0 ° C.).

  Using the receiving layer forming coating solutions 1 to 14 prepared as described above, the undercoat layer 1 forming coating solution, the undercoat layer 2 forming coating solution, and the heat insulating layer forming coating solution are formed on the support. And a coating solution for forming a receiving layer are applied simultaneously, and the coated sample is subjected to a drying process, and then the film surface temperature in the transport process is changed to the transport temperature shown in Tables 1 and 2, A thermal transfer image receiving sheet sample was prepared. The time from the end of the drying process to the start of winding was 7 minutes.

  These image-receiving sheet samples are processed so that they can be loaded into Nidec Copal's sublimation printer DPB2000 (trade name), combined with the above ink sheet, and solid in black (size 4 x 6 inches) in high-speed print mode. 10 sheets were output. The Visual density was measured with a Photographic Densitometer (trade name, manufactured by X-Rite Incorporated), and the average was taken as the print density.

Moreover, the presence or absence of cracks was confirmed for these image receiving sheet samples.
Table 1 shows the presence or absence of cracks in the image-receiving sheet, which is a combination of the solid content ratio of the water-soluble polymer in the receiving layer and the film surface temperature (conveying temperature) in the conveying step. Table 2 shows the print density (transfer density) of the black solid sample.

  From Table 1, it can be seen that the thermal transfer image-receiving sheet produced by the production method of the present invention is free from cracks. Table 2 also shows that a high transfer density is obtained in the heat-sensitive transfer image-receiving sheet produced by the production method of the present invention.

Claims (2)

Sensation having at least one heat insulating layer containing at least one hollow polymer and at least one receiving layer containing at least one polymer latex and at least one water-soluble polymer on the support. A method for producing a thermal transfer image-receiving sheet, comprising:
The coating liquid for forming the receiving layer has a glass transition temperature of 70 ° C. or less of the polymer latex, and the content of the water-soluble polymer with respect to the total solid content is 0.01% by mass or more and 3% by mass. % Is a coating solution for forming a receptor layer,
Applying two or more kinds of coating liquids containing the receiving layer forming coating liquid simultaneously on the support;
A drying step of drying the coating layer applied with the simultaneous multilayer coating;
After the drying step, a conveying step of conveying the coating layer at a film surface temperature of 35 ° C. or less
A winding step of winding up the support on which the coating layer transported in the transporting step is wound, and the time from the end of the drying step to the start of the winding step is within 10 minutes. Production method.   2. The thermal transfer image-receiving sheet according to claim 1, wherein the content of the water-soluble polymer with respect to the total solid content of the receiving layer forming coating solution is 0.01% by mass or more and 1% by mass or less. Production method.