JP5703741B2 - Thermal transfer image-receiving sheet and method for producing the same - Google Patents

Description

  The present invention relates to a base material, a thermal transfer image receiving sheet comprising a heat insulating layer and a receiving layer on the base material in this order, and a method for producing the same.

  Conventionally, various printing methods are known. Among them, the thermal diffusion type transfer method (sublimation type thermal transfer method) uses a sublimation dye as a color material, so that density gradation can be freely adjusted, and intermediate colors and gradations can be adjusted. It has excellent tone reproducibility and can form high-quality images comparable to silver halide photographs.

  This thermal diffusion transfer system is a method in which a thermal transfer ink sheet containing a dye (sublimation dye) and a thermal transfer image receiving sheet are superposed, and then the ink sheet is heated by a thermal head whose heat generation is controlled by an electrical signal. The dye in the ink sheet is transferred to the image receiving sheet to record image information. As such thermal diffusion transfer systems become widespread, the printing speed has been increased, and sufficient color density can be obtained even if the conventional thermal energy is printed using the conventional thermal transfer ink sheet and thermal transfer image receiving sheet. There are problems such as inability to obtain.

  Furthermore, there are various other problems in the thermal diffusion transfer system. For example, due to insufficient releasability of the image receiving sheet, the ink sheet sticks to the receiving layer surface of the image receiving sheet at the time of printing, and when the ink sheet is peeled off from the image receiving layer after printing, generation of peeling sound, Problems such as poor running and occurrence of peeling lines on the image have occurred.

  In order to solve the various problems as described above, a method of hardening a gelatin by adding a specific hardener to the receiving layer of the thermal transfer recording sheet has also been proposed (see, for example, Patent Document 1). . In addition, a dye-receiving layer transfer sheet has been proposed in which a specific amount of all three types of modified silicones of epoxy-modified silicone, methyl-modified silicone, and polyether-modified silicone is added to the dye-receiving layer (see, for example, Patent Document 2). reference).

  However, the development of a thermal transfer image receiving sheet excellent in various properties such as adhesion of each layer of the thermal transfer image receiving sheet, releasability at the time of printing, moisture resistance and heat resistance of the printed material, and image density of the printed material is still desired. ing.

JP 2008-6781 A Japanese Patent No. 4163828

  The present invention has been made in view of the above-described background art, and its purpose is to adhere to each layer of the thermal transfer image-receiving sheet, release property at the time of printing, moisture and heat resistance of the printed material, and image density of the printed material. It is an object of the present invention to provide a thermal transfer image-receiving sheet that can improve various performances and the like, and a method for producing the same.

  In order to solve the above-mentioned problems, the present inventors have intensively studied. As a result, in a thermal transfer image-receiving sheet having at least a heat-insulating layer and a receiving layer in this order on a substrate, a specific silicone release agent for forming the receiving layer It has been found that the above-mentioned problems can be solved by using, and the present invention has been completed.

That is, according to one aspect of the present invention,
A thermal transfer image receiving sheet comprising a base material, and a heat insulating layer and a receiving layer in this order on the base material,
The heat insulating layer comprises hollow particles;
The receiving layer comprises a binder resin and a silicone release agent, and is substantially free of gelatin;
There is provided a thermal transfer image-receiving sheet, wherein the silicone release agent comprises an epoxy-modified silicone having a viscosity of 100 to 10,000 mm ² / s and an epoxy equivalent of 50 to 2000.

According to another aspect of the present invention,
A method for producing a thermal transfer image receiving sheet, comprising a base material, and a heat insulating layer and a receiving layer in this order on the base material,
Using an aqueous coating solution containing hollow particles, forming a heat insulating layer on the substrate;
Using an aqueous dispersion coating solution obtained by mixing an aqueous dispersion in which a binder resin is dispersed and an aqueous dispersion in which a silicone release agent is dispersed and substantially free of gelatin, Forming a receiving layer on the heat insulating layer,
There is provided a method for producing a thermal transfer image-receiving sheet, wherein the silicone release agent comprises an epoxy-modified silicone having a viscosity of 100 to 10000 mm ² / s and an epoxy equivalent of 50 to 2000.

  According to the thermal transfer image receiving sheet of the present invention, it is possible to improve various performances such as adhesion of each layer of the thermal transfer image receiving sheet, releasability at the time of printing, moisture resistance / heat resistance of the printed matter, and image density of the printed matter. A thermal transfer image-receiving sheet and a method for producing the same can be provided.

It is a schematic cross section which shows an example of the thermal transfer image receiving sheet by this invention.

Thermal transfer image receiving sheet The thermal transfer image receiving sheet of the present invention comprises a base material, and a heat insulating layer and a receiving layer on the base material in this order. In a preferred embodiment, the thermal transfer image receiving sheet may further have a primer layer or an intermediate layer between the heat insulating layer and the receiving layer.

  According to one aspect of the present invention, there is provided a thermal transfer image receiving sheet comprising, on a substrate, two heat insulating layers, a primer layer, an intermediate layer, and a receiving layer in this order. Specifically, FIG. 1 shows a schematic sectional view of an example of the thermal transfer image receiving sheet according to the present invention. 1 includes a base material 11, a heat insulating layer (lower layer) 12, a heat insulating layer (upper layer) 13, a primer layer 14, an intermediate layer 15, and a receiving material. The layer 16 is provided in this order.

The base material in the present invention has a role of holding the receiving layer and heat is applied at the time of thermal transfer. Therefore, the base material may be a material having a mechanical strength that does not hinder handling even in a heated state. preferable.

  Examples of such a base material include condenser paper, glassine paper, sulfuric acid paper, high-size paper, synthetic paper (polyolefin-based, polystyrene-based), high-quality paper, art paper, coated paper, and cast-coated paper. , Wallpaper, backing paper, synthetic resin or emulsion impregnated paper, synthetic rubber latex impregnated paper, synthetic resin internal paper, paperboard, cellulose fiber paper, or polyester, polyacrylate, polycarbonate, polyurethane, polyimide, polyetherimide, cellulose derivatives , Polyethylene, ethylene-vinyl acetate copolymer, polypropylene, polystyrene, acrylic, polyvinyl chloride, polyvinylidene chloride, polyvinyl alcohol, polyvinyl butyral, nylon, polyether ether ketone, polysulfone, polyether mon And films such as chlorofluorocarbon, tetrafluoroethylene, perfluoroalkyl vinyl ether, polyvinyl fluoride, tetrafluoroethylene / ethylene, tetrafluoroethylene / hexafluoropropylene, polychlorotrifluoroethylene, and polyvinylidene fluoride. A white opaque film formed by adding a white pigment or a filler to the synthetic resin can be used, and is not particularly limited. Moreover, the laminated body by the arbitrary combinations of the said base material can also be used. Examples of typical laminates include cellulose fiber paper and synthetic paper, or synthetic paper of cellulose synthetic paper and a plastic film. In the present invention, a commercially available base material can be used, and for example, RC paper (manufactured by Mitsubishi Paper Industries Co., Ltd.) is preferred. The thickness of the substrate can be appropriately changed according to the strength and heat resistance required for the thermal transfer image-receiving sheet and the material of the material employed as the substrate. Specifically, the thickness of the substrate is It is preferably in the range of 50 μm to 1000 μm, and more preferably in the range of 100 μm to 300 μm.

Receiving layer The receiving layer in the present invention receives the sublimation dye transferred from the thermal transfer ink sheet during image formation by thermal transfer, and holds the received sublimation dye in the receiving layer, whereby an image is formed on the surface of the receiving layer. Can be formed and maintained. In the present invention, the receiving layer contains a binder resin and a silicone release agent, and is substantially free of gelatin. The receiving layer may further contain a crosslinking agent and other additives. By adding a binder resin and a polyether-modified silicone in combination to the receiving layer, it is possible to simultaneously improve the releasability and the image density performance of the printed matter. Moreover, when forming a receiving layer using a water-system coating liquid, the image density of a printed matter can be improved by adding polyether modified silicone.

  In the present invention, the amount of gelatin contained in the receiving layer is preferably as small as possible and is preferably substantially free of gelatin. “Substantially free” means that no gelatin is intentionally added to modify the properties of the receiving layer. For example, the gelatin content is 1% by mass or less, preferably 0.1% by mass or less, more preferably 0.05% by mass or less, and still more preferably with respect to the solid content mass of the binder resin. Is 0.01 mass% or less. By reducing the amount of gelatin contained in the receiving layer to the above level, the image density and releasability of the printed matter can be improved. Moreover, it is preferable that the film thickness at the time of drying of a receiving layer is 0.5-5.0 micrometers. If the film thickness at the time of drying is in this range, the coating suitability can be further improved.

The binder resin used to form the binder resin receiving layer includes acrylic resins, vinyl chloride resins, polyvinyl chloride resins, polyolefin resins such as polyethylene and polypropylene, polyvinyl chloride, vinyl chloride / vinyl acetate copolymer resins ( Vinyl chloride resin), halogenated polymers such as polyvinylidene chloride, vinyl polymers such as polyvinyl acetate and polyacrylate, polyester resins such as polyethylene terephthalate and polybutylene terephthalate, polystyrene resins, polyamide resins, ethylene And copolymer resins of olefins such as propylene and other vinyl monomers, cellulose resins such as ionomers and cellulose diacetates, polycarbonates and the like, preferably vinyl chloride resins, such as vinyl chloride resins It is at least one selected from the group consisting of salt Biakuriru resins, and vinyl chloride acetate-based resin, particularly preferably a vinyl chloride acetate-based resin. In the present invention, commercially available binder resins can also be used. For example, VB603 (vinyl acetate resin), VB985 (vinyl chloride resin), VB900 (vinyl chloride resin, above, manufactured by Nissin Chemical Industry Co., Ltd.) ) And other solvent-based resins such as sorbine C (vinyl chloride-based resin) and sorbine CN (vinyl chloride-based resin, Nissin Chemical Industry Co., Ltd.) are dispersed in a known manner. And the like. In particular, it is preferable to use a vinyl chloride-based resin from the viewpoints of image preservability (moisture and heat resistance) and releasability, and further, combinations with the following silicone release agents are preferred.

Silicone release agent contained in the receiving layer of silicone release agent present invention has a viscosity 100~10000mm ² / s, preferably 300~9000mm ² / s, more preferably 500~6000mm ² / s, more preferably, It contains an epoxy-modified silicone having a viscosity of 1000 to 3000 mm ² / s and an epoxy equivalent of 50 to 2000, preferably 80 to 1800, more preferably 100 to 1000. The viscosity can be measured by various methods of JIS Z 8803: Viscosity of liquid-Measurement method. The epoxy equivalent (g / eq) is the molecular weight value of the epoxy crosslinking agent per functional group. By using an epoxy-modified silicone having a viscosity of 100 to 10,000 mm ² / s and an epoxy equivalent of 50 to 2000, it is possible to improve the releasability during printing and the heat resistance and moisture resistance of the printed matter. In the present invention, commercially available epoxy-modified silicone can be used, and examples thereof include X22-3000T and KF101 (manufactured by Shin-Etsu Chemical Co., Ltd.). Use of such an epoxy-modified silicone is preferable from the viewpoint of combination with the binder resin.

  In the present invention, the above epoxy-modified silicone may be used alone or in combination of two or more. When mixing 2 or more types, the average value should just be in the said range about each property, such as a viscosity and an epoxy equivalent.

  According to another preferred embodiment, the silicone release agent may further contain a silicone oil other than the above epoxy-modified silicone. Examples of the silicone oil include amino-modified silicone, alcohol-modified silicone, vinyl-modified silicone, urethane-modified silicone, polyester-modified silicone, polyether-modified silicone, polyester-modified silicone, acrylic-modified silicone, aralkyl-modified silicone, and amide-modified silicone. Can be mentioned. In the present invention, an epoxy-modified silicone and one or more other silicone oils may be mixed and used. The mixing ratio of the epoxy-modified silicone and the other silicone oil is preferably 100: 0 to 40:60, more preferably 90:10 to 50:50, and still more preferably 85:15 to 60:40. Good. By using such a mixed silicone release agent, it is possible to improve the releasability at the time of printing in various environments and the heat resistance and moisture resistance of the printed matter.

Crosslinking agent According to a preferred embodiment of the present invention, the crosslinking agent is an epoxy crosslinking agent having an epoxy equivalent of 300 or less, preferably 200 or less and 100 or more, and a functional group number of 2 or more, preferably 4 or more and 10 or less. The inclusion is preferably used. In addition, an epoxy equivalent (g / eq) is a value of the molecular weight of the epoxy crosslinking agent per functional group. Moreover, the functional group number is the number of epoxy groups in one molecule of the epoxy crosslinking agent. That is, it can be said that the smaller the epoxy equivalent and the greater the number of functional groups, the higher the crosslinking effect as a crosslinking agent. Various performances such as image density can be improved by using a cross-linking agent including an epoxy cross-linking agent having a small epoxy equivalent and the number of functional groups within the above range. In the present invention, the epoxy group of the crosslinking agent reacts with the carboxyl group of the component in the coating layer to crosslink part or all of the resin, whereby various performances such as image density can be improved.

  According to a preferred embodiment of the present invention, the content of the cross-linking agent is preferably 1 to 30% by mass, based on the total solid content mass of the resin (total of binder resin, hydrophilic binder, hollow particles and the like). Preferably it is 1-15 mass%, More preferably, it is 1-10 mass%. When the content of the crosslinking agent is in the above range, various performances such as image density can be further improved. In the present invention, a commercially available epoxy crosslinking agent can also be used, and examples thereof include EX512, EX521, EX851, EX832 (above, Nagase ChemteX Corporation), CR5L (DIC Corporation), and the like. In addition, you may add the crosslinking agent containing said epoxy crosslinking agent to any one layer or more or all the layers (for example, a receiving layer, a heat insulation layer, and an intermediate | middle layer) in the receiving layer surface side of a base material.

Thermal insulation layer The thermal insulation layer in the present invention has thermal insulation and cushioning properties that can prevent heat applied during image formation by thermal transfer from being lost due to heat transfer to a substrate or the like. The heat insulation layer in the present invention contains hollow particles, and may further contain the above-mentioned crosslinking agent, the above-mentioned hydrophilic binder, and other additives. A heat insulation layer can be provided with cushioning properties by including hollow particles. Moreover, according to a preferable aspect, a heat insulation layer may consist of two or more layers. By providing two or more heat insulating layers in this way, the heat insulating properties and cushioning properties that affect the print quality and the adhesion to the substrate can be improved. Here, the degree of cushioning property of the heat insulating layer can be appropriately adjusted according to the application of the thermal transfer image receiving sheet. In addition, the degree of cushioning property of the heat insulating layer can be adjusted to an arbitrary range by changing the thickness of the heat insulating layer, for example. The thickness of the heat insulating layer is not particularly limited as long as the heat insulating property, cushioning property and the like can be adjusted to a desired level, but preferably within a range of 10 μm to 100 μm, and within a range of 10 μm to 50 μm. More preferably, it is within. The density of the thermal insulating layer, for example in the range of ^{0.1g / cm 3 ~0.8g / cm 3} , preferably in the range of inter alia ^{0.2g / cm 3 ~0.7g / cm 3} .

Hollow particles The volume average particle size of the hollow particles used in the present invention is preferably 0.1 to 10 µm, more preferably 0.3 to 5 µm. If the volume average particle diameter of the hollow particles is in the above range, heat insulating properties and cushioning properties can be imparted to the heat insulating layer. The average hollowness of the hollow particles is preferably 20% or more, more preferably 30 to 80%. If the average hollowness of the hollow particles is in the above range, heat insulating properties and cushioning properties can be imparted to the heat insulating layer. Furthermore, the organic hollow particle comprised from resin etc. may be sufficient, and the inorganic hollow particle comprised from glass etc. may be sufficient. The hollow particles may be cross-linked hollow particles. In the present invention, commercially available hollow particles can also be used. For example, HP-1055, HP-91, Ropeke SE (manufactured by Rohm and Haas Co., Ltd.), MH-5055 (Nippon Zeon) and the like are preferable.

Hydrophilic binder According to a preferred embodiment of the present invention, the hydrophilic binder contained in the heat-insulating layer and the primer layer and intermediate layer described below includes gelatin and derivatives thereof, polyvinyl alcohol, polyethylene oxide, polyvinyl pyrrolidone, pullulan, Mention may be made of carboxymethylcellulose, hydroxyethylcellulose, dextran, dextrin, polyacrylic acid and its salts, agar, κ-carrageenan, λ-carrageenan, ι-carrageenan, casein, xanthene gum, locust bean gum, alginic acid, and gum arabic. Particularly preferred is gelatin. By using such a hydrophilic binder, interlayer adhesion of each layer such as a heat insulating layer and an intermediate layer can be improved. In particular, when each layer is formed by an aqueous coating method and a simultaneous multilayer coating method, the suitability of coating can be improved by using gelatin. Moreover, the viscosity of each coating liquid can be adjusted to a desired range, and a desired film thickness can be obtained. In the present invention, commercially available gelatin can also be used, and for example, RR, R, CLV (manufactured by Nitta Gelatin Co., Ltd.) and the like are preferable.

Primer layer The primer layer in the present invention is provided between the heat insulating layer and the receiving layer, and has a role of satisfactorily bonding the heat insulating layer and the receiving layer, and heat insulation of the dye in a high temperature and high humidity environment. It has a function of improving the image storage stability by preventing migration to the layer side. In a preferred embodiment, the primer layer contains the hollow particles, the hydrophilic binder, and the binder resin, and the binder resin preferably contains an acrylic resin. Although it does not specifically limit as thickness of a primer layer, For example, it is preferable that they are 1 micrometer-40 micrometers, 1 micrometer-20 micrometers are more preferable, and 1 micrometer-10 micrometers are more preferable.

  In the present invention, the acrylic resin refers to a polymer of acrylic acid or methacrylic acid monomer or derivative thereof, a polymer of acrylic acid ester or methacrylic acid ester monomer or derivative thereof, acrylic acid or methacrylic acid monomer and other derivatives. It includes a copolymer with a monomer or a derivative thereof, and a copolymer of a monomer of an acrylate ester or a methacrylate ester with another monomer or a derivative thereof.

  According to a preferred embodiment of the present invention, the acrylic resin is preferably a copolymer of an acrylic ester or methacrylic ester monomer and another monomer or a derivative thereof. Examples of the acrylic acid ester or methacrylic acid ester monomer include alkyl acrylate and alkyl methacrylate, preferably methyl acrylate, methyl methacrylate, ethyl acrylate, ethyl methacrylate, butyl acrylate, butyl methacrylate, lauryl acrylate, and lauryl methacrylate. Can be mentioned. Examples of other monomers include aromatic hydrocarbons, aryl group-containing compounds, amide group-containing compounds, and vinyl chloride, preferably styrene, benzylstyrene, phenoxyethyl methacrylate, acrylamide, and methacrylamide. it can. In the present invention, a copolymer of an alkyl acrylate or an alkyl methacrylate and at least one other monomer selected from the group consisting of an aromatic hydrocarbon, an aryl group-containing compound, and an amide group-containing compound, or a derivative thereof. It is particularly preferable to use it. By copolymerizing the monomers as described above, the concentration and releasability can be improved. Two or more acrylic resins may be mixed and used.

Intermediate layer The intermediate layer in the present invention is provided between the primer layer and the receiving layer, and has a role of satisfactorily bonding the primer layer and the receiving layer, and is a lower layer of the dye in a high temperature and high humidity environment. It has a function of preventing image transfer to the side (heat insulating layer side) and improving image storage stability. The intermediate layer can be formed using the same binder resin as that for the receiving layer in order to improve the adhesion with the receiving layer. The intermediate layer may contain a hydrophilic binder.

Other Layers In the present invention, other layers may be provided in addition to the above heat insulating layer, primer layer, intermediate layer, and receptor layer. By providing other layers, functions such as solvent resistance, dye diffusion barrier during image storage under high temperature / high humidity, interlayer adhesion, whitening, glare / unevenness of the substrate, and antistatic functions Can be added. Known means can be used as the means for forming the other layers. For example, fluorescent brighteners, inorganic fine particles, hollow fine particles, and organic conductive materials such as conductive fillers and polyaniline sulfonic acid, etc. The method of adding is mentioned.

Method for Producing Thermal Transfer Image-Receiving Sheet The method for producing a thermal transfer image-receiving sheet of the present invention is a method for producing a thermal transfer image-receiving sheet comprising a substrate, a heat insulating layer, and a receptor layer in this order on the substrate. And
A step of forming a heat insulating layer on the substrate using an aqueous coating solution containing hollow particles;
Using an aqueous dispersion coating solution obtained by mixing an aqueous dispersion in which a binder resin is dispersed and an aqueous dispersion in which a silicone release agent is dispersed and substantially free of gelatin, Forming a receiving layer on the heat insulating layer. Further, the silicone release agent comprises an epoxy-modified silicone having a viscosity of 100 to 10,000 mm ² / s and an epoxy equivalent of 50 to 2000. The epoxy-modified silicone is as described above. In the present invention, by using the above specific epoxy-modified silicone, it can be sufficiently dispersed in an aqueous solution without using gelatin. As described above, by using an aqueous dispersion coating solution obtained by mixing an aqueous solution in which a binder resin and a silicone release agent are dispersed separately, a receiving layer is formed on the heat insulating layer, thereby forming silicone. The release agent can phase separate during drying and bleed out to the outermost surface, thereby increasing the silicone density on the surface. Moreover, when a receiving layer is formed by simultaneous multilayer coating, the migration of the silicone release agent to the lower layer can be suppressed, and the surface silicone density can be increased. Furthermore, in the present invention, since the receiving layer can be formed using an aqueous dispersion coating solution in which epoxy-modified silicone is sufficiently dispersed without using gelatin, the image density of the printed matter can be improved.

  In the present invention, an aqueous dispersion in which the above silicone release agent is dispersed and substantially free of gelatin can be prepared by the following method. First, an aqueous solution and a solvent solution were prepared separately. The aqueous solution is obtained by mixing a known dispersant and water. On the other hand, the solvent-based solution is obtained by mixing the above silicone release agent and a known organic solvent (solvent). The aqueous solution and the solvent solution are mixed and stirred, and then dispersed using a homogenizer to prepare a dispersion. Thereafter, the solvent is removed under reduced pressure while heating the dispersion to 30 to 60 ° C., the volume change of the solvent is corrected by adding pure water, and the solid content is prepared to obtain an aqueous dispersion. It is done.

  According to another preferred embodiment, the binder resin contained in the aqueous dispersion coating liquid for forming the receiving layer is preferably a vinyl acetate resin. Moreover, it is preferable that the water-system coating liquid which forms a heat insulation layer, and / or the water-system dispersion coating liquid which forms a receiving layer further contain an epoxy crosslinking agent. In addition, about binder resin and an epoxy crosslinking agent, it is as having demonstrated above.

  According to another aspect, it is preferable that the method further includes a step of forming a primer layer between the step of forming the heat insulating layer and the step of forming the receiving layer. The primer layer can be formed using an aqueous coating solution comprising the hollow particles, the hydrophilic binder, and a binder resin, preferably the acrylic resin.

  According to a preferred embodiment, the step of forming the heat insulating layer and the step of forming the receiving layer may be performed simultaneously. Furthermore, it is particularly preferable that all layers constituting the receiving layer from the heat insulating layer are formed by an aqueous coating method and a simultaneous multilayer coating method. By such a manufacturing method, effects such as improvement in interlayer adhesion of each layer of the thermal transfer image-receiving sheet and cost improvement can be obtained. When simultaneous multi-layer coating is performed in this way, a surface tension can be adjusted by adding a surfactant to the coating solution for forming each layer. Examples of the surfactant include Surfynol 440 (manufactured by Nissin Chemical Industry Co., Ltd.).

  For the application of each layer of the thermal transfer image-receiving sheet, a known method such as roll coating, bar coating, gravure coating, gravure reverse coating, die coating, slide coating, curtain coating, etc. can be used. A method in which these layers can be applied simultaneously is preferred.

  According to a preferred aspect of the present invention, the method for producing a thermal transfer image-receiving sheet of the present invention may further include a setting step and a drying step after forming a receiving layer and other layers on a substrate by coating. Good. The setting step referred to in the present invention means, for example, increasing the viscosity of the coating composition by means of, for example, blowing cold air or the like onto the coating surface on the support to lower the temperature, and the material fluidity between each layer and each layer. It is a process of promoting gelation that slows down. The temperature condition when using cold air is preferably 25 ° C. or less, and more preferably 10 ° C. or less. Further, the time for which the coating film is exposed to cold air is preferably 10 seconds or more and 120 seconds or less, although it depends on the coating conveyance speed.

Thermal transfer ink sheet The thermal transfer ink sheet used together with the thermal transfer image-receiving sheet of the present invention is provided with a heat transferable color material layer on one side of the base sheet and a heat resistant slipping layer on the other side of the base sheet. It is preferable to have a layer structure. Hereinafter, each layer constituting the thermal transfer ink sheet will be described.

As the material of the base sheet constituting the thermal transfer ink sheet used in the present invention, a conventionally known material can be used, and even if it is other than that, it has a certain degree of heat resistance and strength. Can be used. For example, polyethylene terephthalate, polyester, polypropylene, polycarbonate, polyethylene, polystyrene, polyvinyl alcohol, polyvinyl chloride, polyvinylidene chloride, polyimide, nylon, cellulose acetate, ionomer and other resin films, condenser paper, paraffin paper, and other non-woven fabrics Etc. These may be used alone, or a laminate in which these are arbitrarily combined may be used. Among these, polyethylene terephthalate which is a versatile plastic that can be thinned and is inexpensive is preferable.

  The thickness of the base sheet can be appropriately selected according to the material so that the strength, heat resistance and the like are appropriate, but is usually preferably about 0.5 to 50 μm, more preferably 1 to 20 μm, and further Preferably it is 1-10 micrometers.

  The base sheet may be subjected to a surface treatment in order to improve adhesion with an adjacent layer. As the surface treatment, known resin surface modification techniques such as corona discharge treatment, flame treatment, ozone treatment, ultraviolet treatment, radiation treatment, surface roughening treatment, chemical treatment, plasma treatment, and grafting treatment are applied. can do. Only one type of the surface treatment may be applied, or two or more types may be applied.

  Furthermore, it is also possible to apply and form an adhesive layer on the base sheet as an adhesive treatment of the base sheet. An adhesion layer can be formed from the following organic materials and inorganic materials, for example. Examples of the organic material include polyester resins, polyacrylate resins, polyvinyl acetate resins, polyurethane resins, styrene acrylate resins, polyacrylamide resins, polyamide resins, polyether resins, polystyrene resins, Examples thereof include polyethylene resins, polypropylene resins, polyvinyl chloride resins, polyvinyl alcohol resins, polyvinyl pyrrolidone and vinyl resins such as modified products thereof, and polyvinyl acetal resins such as polyvinyl acetoacetal and polyvinyl butyral. Examples of the inorganic material include silica (colloidal silica), alumina or alumina hydrate (alumina sol, colloidal alumina, cationic aluminum oxide or hydrate, suspicion bakumaite, etc.), aluminum silicate, magnesium silicate, magnesium carbonate, oxidation Examples thereof include ultrafine particles of colloidal inorganic pigments such as magnesium and titanium oxide.

  Moreover, when manufacturing a plastic film by extending | stretching as said surface treatment, a primer liquid can be apply | coated to an unstretched film and it can also carry out by extending | stretching after that (primer process).

Thermal transferable color material layer The thermal transfer ink sheet used in the present invention is provided with a thermal transferable color material layer on one surface of a substrate sheet. When the thermal transfer ink sheet is a sublimation type thermal transfer ink sheet, a layer containing a sublimation dye is formed as the thermal transferable color material layer, and when the thermal transfer type thermal transfer ink sheet is a hot melt composition containing a colorant A layer containing a heat-meltable ink is formed. A layer region containing a sublimable dye and a layer region containing a heat-meltable ink composed of a heat-melting composition containing a colorant are provided in a surface sequence on a continuous base sheet. Also good.

  As the material of the heat transferable color material layer, conventionally known dyes can be used, but those having good characteristics as a printing material, for example, having a sufficient coloring density and changing color due to light, heat, temperature, etc. Those that do not are preferred. For example, as a red dye, MS Red G (manufactured by Mitsui Toatsu Chemical Co., Ltd.), Macrolex Red Violet R (manufactured by Bayer), CeresRed 7B (manufactured by Bayer), Samalon Red F3BS (manufactured by Mitsubishi Chemical), etc. are yellow. Examples of the dye include Holon Brilliant Yellow 6GL (manufactured by Clariant), PTY-52 (manufactured by Mitsubishi Kasei Co., Ltd.), Macrolex Yellow 6G (manufactured by Bayer), etc., and examples of the blue dye include Kayaset Blue 714 (Nippon Kayaku Co., Ltd.). Manufactured), Waxoline Blue AP-FW (manufactured by ICI), Holon Brilliant Blue SR (manufactured by Sand), MS Blue 100 (manufactured by Mitsui Toatsu Chemicals) and the like.

  Examples of the binder resin for supporting the dye include cellulose resins such as ethyl cellulose resin, hydroxyethyl cellulose resin, ethyl hydroxy cellulose resin, methyl cellulose resin, and cellulose acetate resin, polyvinyl alcohol resin, polyvinyl acetate resin, and polyvinyl butyral resin. And vinyl resins such as polyvinyl acetal resin and polyvinyl pyrrolidone, acrylic resins such as poly (meth) acrylate and poly (meth) acrylamide, polyurethane resins, polyamide resins, and polyester resins. Among these, cellulose-based, vinyl-based, acrylic-based, polyurethane-based, and polyester-based resins are preferable from the viewpoints of heat resistance, dye transferability, and the like.

  Examples of the method for forming the heat transferable color material layer include the following methods. For the heat-transferable colorant layer obtained by adding additives such as a release agent to the above dyes and binder resin, if necessary, dissolved in an appropriate organic solvent such as toluene or methyl ethyl ketone, or dispersed in water. A coating solution (solution or dispersion) is applied to one surface of a base sheet by, for example, a gravure printing method, a reverse roll coating method using a gravure plate, a roll coater, a bar coater, etc. It can be formed by drying. The heat transferable color material layer has a thickness of about 0.2 to 5.0 μm, and the content of the sublimable dye in the heat transferable color material layer is 5 to 90% by weight, preferably 5 to 70% by weight. It is preferable that

Protective layer The thermal transfer ink sheet used in the present invention may be provided with a protective layer in the surface order on the same side as the thermal transferable color material layer. After the color material is transferred to the thermal transfer image-receiving sheet, the protective layer is transferred to cover the image, whereby the image can be protected from light, gas, liquid, abrasion and the like. Other layers such as an adhesive layer, a release layer, a release layer, or an undercoat layer may be provided as a protective layer.

Heat-resistant slip layer The heat-resistant slip layer is mainly composed of a heat-resistant resin. The heat resistant resin is not particularly limited. For example, polyvinyl butyral resin, polyvinyl acetoacetal resin, polyester resin, vinyl chloride-vinyl acetate copolymer resin, polyether resin, polybutadiene resin, styrene-butadiene copolymer resin, Acrylic polyol, polyurethane acrylate, polyester acrylate, polyether acrylate, epoxy acrylate, urethane or epoxy prepolymer, nitrocellulose resin, cellulose nitrate resin, cellulose acetate propionate resin, cellulose acetate butyrate resin, cellulose acetate-hydrodiene Phthalate resin, cellulose acetate resin, aromatic polyamide resin, polyimide resin, polyamideimide resin, polycarbonate resin, Fine chlorinated polyolefin resins.

  The heat resistant slipping layer may be formed by blending additives such as a slipperiness imparting agent, a crosslinking agent, a release agent, an organic powder, and an inorganic powder in addition to the above heat resistant resin.

In general, the heat-resistant slipping layer is formed by adding the above-mentioned heat-resistant resin, and the above-described slipperiness-imparting agent and additives that are optionally added to the solvent, and dissolving or dispersing each component to thereby apply the heat-resistant slipping layer coating solution. Then, the heat resistant slipping layer coating solution can be coated on a substrate and dried.
As the solvent in the heat resistant slipping layer coating solution, the same solvent as that in the dye ink can be used.

Examples of the coating method of the heat resistant slipping layer coating liquid include wire bar coating, gravure printing, screen printing, reverse roll coating using a gravure plate, and gravure coating is particularly preferable. Heat-resistant slip layer coating solution, dry coating amount is preferably 0.1 to 3 g / ^{m 2,} more preferably may be applied so as to be 1.5 g / ^{m 2} or less.

Image Forming Method In the image forming method using the thermal transfer image receiving sheet of the present invention, the thermal transfer image receiving sheet and the thermal transfer ink sheet containing a heat diffusible dye are overlaid and heated in accordance with a recording signal, thereby transferring the thermal transfer image. An image can be formed by transferring the thermal diffusible dye contained in the ink sheet to the thermal transfer image-receiving sheet.

  As a thermal transfer recording apparatus that can be used in such an image forming method, a known apparatus can be used and is not particularly limited. In the present invention, a commercially available thermal transfer recording apparatus can be used, and examples include a sublimation thermal transfer printer (manufactured by ALTECH ADS, model: MEGAPIXEL III).

  EXAMPLES Hereinafter, the present invention will be described in more detail with reference to examples and comparative examples, but the present invention is not construed as being limited to the contents of the following examples. In addition, the weight part of description was described by solid content, it diluted using the pure water, and it adjusted so that the total solid content of each coating liquid might be 15-30%.

Example 1
Preparation of thermal transfer image-receiving sheet 1 RC paper (manufactured by Mitsubishi Paper Industries Co., Ltd.) was used as a base sheet, and coating solution 1-2 for heat insulation layer (for lower layer) and coating solution 1-1 for heat insulation layer (upper layer) having the following composition: ), Primer layer coating solution 1, intermediate layer coating solution 1 and receptor layer coating solution 1 (aqueous dispersion coating solution) are heated to 40 ° C., respectively, and slide coating is used to determine the thickness when dried. The coating was applied to 2 μm, 12 μm, 3.5 μm, 1.5 μm, and 3 μm, cooled at 5 ° C. for 30 seconds, and then dried at 50 ° C. for 2 minutes to obtain a thermal transfer image-receiving sheet 1 (layer structure: substrate / A heat insulating layer (lower layer) / heat insulating layer (upper layer) / primer layer / intermediate layer / receiving layer) was obtained. This thermal transfer image-receiving sheet had a layer structure as shown in FIG.
Composition of coating solution 1-2 for heat insulation layer (for lower layer) MH5055 (hollow particles, Nippon Zeon Co., Ltd., volume average particle size 0.5 μm) 60 parts by weight RR (gelatin, Nitta Gelatin Co., Ltd.) ) 20 parts by weight DM820 (MBR, manufactured by DIC Corporation) 20 parts by weight
Composition of coating solution 1-1 for heat insulating layer (for upper layer) MH5055 (hollow particles, Nippon Zeon Co., Ltd., volume average particle size 0.5 μm) 70 parts by weight RR (gelatin, Nitta Gelatin Co., Ltd.) ) 25 parts by weight / AP40 (aqueous polyurethane resin, manufactured by DIC Corporation) 5 parts by weight
Composition of primer layer coating solution 1 SX866 (crosslinked hollow particles, JSR Corporation, volume average particle size 0.1 μm, porosity 30%)
70 parts by weight RR (gelatin, manufactured by Nitta Gelatin Co., Ltd.) 15 parts by weight NKJ300 (methacrylic acid ester / acrylic copolymer, Shin Nakamura Chemical Co., Ltd.)
15 parts by weight
Composition of intermediate layer coating solution 1 VB603 (vinyl chloride resin, Nissin Chemical Industry Co., Ltd.) 100 parts by weight RR (gelatin, Nitta Gelatin Co., Ltd.) 10 parts by weight
Composition of coating solution 1 for receiving layer VB603 (vinyl acetate resin, manufactured by Nissin Chemical Industry Co., Ltd., already in an aqueous dispersion at the time of commercialization)
100 parts by weight. X22-3000T (epoxy-modified silicone, manufactured by Shin-Etsu Chemical Co., Ltd.) aqueous dispersion
14 parts by weight · EX512 (epoxy crosslinking agent, manufactured by Nagase ChemteX Corporation, epoxy equivalent: 168, functional group number: 4) 5 parts by weight

The above X22-3000T (silicone) aqueous dispersion was dispersed as follows to prepare an aqueous dispersion. First, an aqueous solution 1 and a solvent-based solution 1 were prepared so as to have the following composition. The aqueous solution 1 and the solvent solution 1 were mixed and stirred, and then dispersed using a homogenizer to prepare a dispersion. Then, the dispersion was desolvated under reduced pressure while warming to 30 to 60 ° C., the volume change of the desolvent was corrected by adding pure water, and the solid content was adjusted to 18%. An aqueous dispersion was obtained.
Composition of aqueous solution 1-10 parts by weight of triisopropyl naphthalene sulfonic acid Na salt (dispersant, solid content 10%)-56 parts by weight of pure water
Composition of solvent-based solution 1 X-22-3000T (solvent-based silicone mold release agent (epoxy-modified silicone), Shin-Etsu Chemical Co., Ltd., solid content 100%) 17 parts by weight ethyl acetate (silicone mold release agent dissolved) Solvent) 17 parts by weight

Example 2
Preparation of thermal transfer image-receiving sheet 2 A thermal transfer image-receiving sheet 3 was prepared in the same manner as in Example 1 except that the composition of the coating solution for the heat insulating layer (for the upper layer) and the coating solution for the receiving layer were as follows.
Composition of coating solution 2-1 for heat insulation layer (for upper layer) MH5055 (hollow particles, manufactured by Nippon Zeon Co., Ltd., volume average particle size 0.5 μm) 70 parts by weight RR (gelatin, manufactured by Nitta Gelatin Co., Ltd.) ) 25 parts by weight · AP40 (aqueous polyurethane resin, manufactured by DIC Corporation) 5 parts by weight · EX512 (epoxy crosslinking agent, manufactured by Nagase ChemteX Corporation) 5 parts by weight
Composition of coating solution 2 for receiving layer: VB603 (vinyl acetate resin, manufactured by Nissin Chemical Industry Co., Ltd.) 100 parts by weight. X22-3000T (epoxy-modified silicone, manufactured by Shin-Etsu Chemical Co., Ltd.) aqueous dispersion
14 parts by weight

Example 3
Preparation of thermal transfer image receiving sheet 3 A thermal transfer image receiving sheet 3 was prepared in the same manner as in Example 1 except that no intermediate layer was provided.

Example 4
Preparation of thermal transfer image-receiving sheet 4 A thermal transfer image-receiving sheet 4 was prepared in the same manner as in Example 3 except that the composition of the coating solution for the receiving layer was as follows.
Composition of coating liquid 4 for receiving layer: VB603 (vinyl chloride-based resin, manufactured by Nissin Chemical Industry Co., Ltd.) 100 parts by weight KF101 (epoxy-modified silicone, manufactured by Shin-Etsu Chemical Co., Ltd.) Aqueous dispersion 14 parts by weight -EX512 (epoxy crosslinking agent, manufactured by Nagase ChemteX Corporation) 5 parts by weight The method for preparing the KF101 aqueous dispersion is the same as the method for preparing the X22-3000T aqueous dispersion in Example 1.

Example 5
Preparation of thermal transfer image-receiving sheet 5 A thermal transfer image-receiving sheet 5 was prepared in the same manner as in Example 3 except that the composition of the coating solution for the receiving layer was as follows.
Composition of coating solution 5 for receiving layer: VB603 (vinyl acetate resin, manufactured by Nissin Chemical Industry Co., Ltd.) 100 parts by weight X22-3000T (epoxy-modified silicone, manufactured by Shin-Etsu Chemical Co., Ltd.) and KF410 (aralkyl) 14 parts by weight of an aqueous dispersion of a mixture of modified silicone (manufactured by Shin-Etsu Chemical Co., Ltd.) (mixing ratio 65:35), EX512 (epoxy crosslinking agent, manufactured by Nagase ChemteX Corporation) 5 parts by weight X22-3000T The method for preparing the aqueous dispersion of the mixture of KF410 and KF410 is the same as the method for preparing the X22-3000T aqueous dispersion of Example 1.

Example 6
Preparation of thermal transfer image receiving sheet 6 A thermal transfer image receiving sheet 6 was prepared in the same manner as in Example 3 except that the composition of the coating solution for the receiving layer was as follows.
Composition of coating solution 6 for receiving layer: VB603 (vinyl acetate resin, manufactured by Nissin Chemical Industry Co., Ltd.) 100 parts by weight X22-3000T (epoxy-modified silicone, manufactured by Shin-Etsu Chemical Co., Ltd.) and KF410 (aralkyl) 14 parts by weight of an aqueous dispersion of a mixture of modified silicone (manufactured by Shin-Etsu Chemical Co., Ltd.) (mixing ratio 75:25) and EX512 (epoxy crosslinking agent, manufactured by Nagase ChemteX Corporation) 5 parts by weight X22-3000T The method for preparing an aqueous dispersion of a mixture of KF410 and KF410 is the same as in Example 5.

Example 7
Preparation of thermal transfer image-receiving sheet 7 A thermal transfer image-receiving sheet 7 was prepared in the same manner as in Example 3 except that the composition of the coating solution for the receiving layer was as follows.
Composition of coating solution 7 for receiving layer: VB603 (vinyl chloride resin, manufactured by Nissin Chemical Industry Co., Ltd.) 100 parts by weight. X22-3000T (epoxy-modified silicone, manufactured by Shin-Etsu Chemical Co., Ltd.) and KF410 (aralkyl) 14 parts by weight of an aqueous dispersion of a mixture of modified silicone (manufactured by Shin-Etsu Chemical Co., Ltd.) (mixing ratio 85:15) and EX512 (epoxy crosslinking agent, manufactured by Nagase ChemteX Corporation) 5 parts by weight X22-3000T The method for preparing an aqueous dispersion of a mixture of KF410 and KF410 is the same as in Example 5.

Example 8
Preparation of thermal transfer image receiving sheet 8 A thermal transfer image receiving sheet 8 was prepared in the same manner as in Example 3 except that the composition of the coating solution for the receiving layer was as follows.
Composition of coating solution 8 for receiving layer VB985 (vinyl chloride resin, manufactured by Nissin Chemical Industry Co., Ltd., already in the state of an aqueous dispersion when commercially available)
100 parts by weight. X22-3000T (epoxy-modified silicone, manufactured by Shin-Etsu Chemical Co., Ltd.) aqueous dispersion
14 parts by weight / EX512 (epoxy crosslinking agent, manufactured by Nagase ChemteX Corporation) 5 parts by weight

Example 9
Preparation of thermal transfer image-receiving sheet 9 A thermal transfer image-receiving sheet 9 was prepared in the same manner as in Example 3 except that the composition of the coating solution for the receiving layer was as follows.
Composition of coating solution 9 for receiving layer: VB900 (vinyl chloride resin, manufactured by Nissin Chemical Industry Co., Ltd., already in an aqueous dispersion at the time of commercialization) 100 parts by weight. X22-3000T (epoxy-modified silicone, Shin-Etsu Chemical ( Aqueous dispersion
14 parts by weight / EX512 (epoxy crosslinking agent, manufactured by Nagase ChemteX Corporation) 5 parts by weight

Example 10
Preparation of thermal transfer image-receiving sheet 10 A thermal transfer image-receiving sheet 10 was prepared in the same manner as in Example 3 except that the composition of the coating solution for the receiving layer was as follows.
Composition of coating solution 10 for receiving layer: 100 parts by weight of an aqueous dispersion of sorbine C (a vinyl chloride-based resin, manufactured by Nissin Chemical Industry Co., Ltd.) X22-3000T (epoxy-modified silicone, manufactured by Shin-Etsu Chemical Co., Ltd.) ) Aqueous dispersion
14 parts by weight / EX512 (epoxy crosslinking agent, manufactured by Nagase ChemteX Corporation) 5 parts by weight The aqueous dispersion of sorbine C was dispersed in water by a known method and used in the state of dispersion.

Example 11
Preparation of thermal transfer image receiving sheet 11 A thermal transfer image receiving sheet 11 was prepared in the same manner as in Example 3 except that the composition of the coating solution for the receiving layer was as follows.
Composition of coating solution 11 for receiving layer: 100 parts by weight of aqueous dispersion of sorbine CN (vinyl chloride-based resin, manufactured by Nissin Chemical Industry Co., Ltd.) X22-3000T (epoxy-modified silicone, manufactured by Shin-Etsu Chemical Co., Ltd.) ) Aqueous dispersion
14 parts by weight / EX512 (epoxy crosslinking agent, manufactured by Nagase ChemteX Corp.) 5 parts by weight The aqueous dispersion of sorbine CN was dispersed in water by a known method and used in the state of dispersion.

Comparative Example 1
Preparation of thermal transfer image receiving sheet 12 A thermal transfer image receiving sheet 12 was prepared in the same manner as in Example 3 except that the composition of the coating solution for the receiving layer was as follows.
Composition of coating solution 12 for receiving layer: VB603 (vinyl acetate resin, manufactured by Nissin Chemical Industry Co., Ltd.) 100 parts by weight KF615A (polyether-modified silicone, manufactured by Shin-Etsu Chemical Co., Ltd.) 14 parts by weight: EX512 (Epoxy crosslinking agent, manufactured by Nagase ChemteX Corporation) 5 parts by weight

Comparative Example 2
Preparation of thermal transfer image receiving sheet 13 A thermal transfer image receiving sheet 13 was prepared in the same manner as in Example 3 except that the composition of the coating solution for the receiving layer was as follows.
Composition of coating solution 13 for receiving layer: VB603 (vinyl acetate resin, manufactured by Nissin Chemical Industry Co., Ltd.) 100 parts by weight X22-173DX (epoxy-modified silicone, manufactured by Shin-Etsu Chemical Co., Ltd.) aqueous dispersion
14 parts by weight · EX512 (epoxy crosslinking agent, manufactured by Nagase ChemteX Corporation) 5 parts by weight The method for preparing the X22-173DX aqueous dispersion is the same as the method for preparing the X22-3000T aqueous dispersion in Example 1. is there.

Comparative Example 3
Preparation of thermal transfer image-receiving sheet 14 A thermal transfer image-receiving sheet 14 was prepared in the same manner as in Example 3 except that the composition of the coating solution for the receiving layer was as follows.
Composition of coating solution 14 for receiving layer: VB603 (vinyl acetate resin, manufactured by Nissin Chemical Industry Co., Ltd.) 100 parts by weight TSF4730 * (epoxy-modified silicone, manufactured by Momentive Performance Materials Japan GK) 14 parts by weight of dispersion / EX512 (epoxy crosslinking agent, manufactured by Nagase ChemteX Corp.) 5 parts by weight The method for preparing the X22-173DX aqueous dispersion is the same as the method for preparing the X22-3000T aqueous dispersion of Example 1. It is the same.

Comparative Example 4
Preparation of thermal transfer image-receiving sheet 15 A thermal transfer image-receiving sheet 15 was prepared in the same manner as in Example 3 except that the composition of the coating solution for the receiving layer was as follows. However, since the coating solution was repelled when applied to the substrate, a thermal transfer image receiving sheet could not be produced.
Composition of coating liquid 15 for receiving layer: VB603 (vinyl acetate resin, Nissin Chemical Industry Co., Ltd.) 100 parts by weight KF100T (= KF1001, epoxy-modified silicone, Shin-Etsu Chemical Co., Ltd.) aqueous dispersion 14 parts by weight · EX512 (epoxy crosslinking agent, manufactured by Nagase ChemteX Corporation) 5 parts by weight The method for preparing the KF100T aqueous dispersion is the same as the method for preparing the X22-3000T aqueous dispersion in Example 1.

Comparative Example 5
Preparation of thermal transfer image receiving sheet 16 A thermal transfer image receiving sheet 16 was prepared in the same manner as in Example 3 except that the composition of the coating solution for the receiving layer was as follows.
Composition of coating solution 16 for receiving layer: VB603 (vinyl acetate resin, manufactured by Nissin Chemical Industry Co., Ltd.) 100 parts by weight. FZ4602 (epoxy-modified silicone, manufactured by Toray Dow Corning Co., Ltd.). 14 parts by weight / EX512 (epoxy crosslinking agent, manufactured by Nagase ChemteX Corporation) 5 parts by weight

Comparative Example 6
Preparation of thermal transfer image-receiving sheet 17 A thermal transfer image-receiving sheet 17 was prepared in the same manner as in Example 3 except that the composition of the coating solution for the receiving layer was as follows.
Composition of coating solution 17 for receiving layer VB603 (vinyl chloride resin, manufactured by Nissin Chemical Industry Co., Ltd.) 100 parts by weight RR (gelatin, manufactured by Nitta Gelatin Co., Ltd.) 10 parts by weight X22-3000T ( Epoxy-modified silicone, manufactured by Shin-Etsu Chemical Co., Ltd.) aqueous dispersion
14 parts by weight / EX512 (epoxy crosslinking agent, manufactured by Nagase ChemteX Corporation) 5 parts by weight

Table 1 shows the viscosity and epoxy equivalent of the silicone release agents used in Examples 1 to 11 and Comparative Examples 1 to 6.

Evaluation of Thermal Transfer Image Receiving Sheet For the thermal transfer image receiving sheets 1 to 14, 16, and 17 produced above, (1) release property evaluation, (2) moisture and heat resistance evaluation, (3) adhesion evaluation, and (4) Image density evaluation was performed.

(1) Evaluation of releasability The sublimation type thermal transfer printer (manufactured by ALTECH ADS, model: MEGAIXELIII) and the genuine ink ribbon of the printer were placed in a high temperature and high humidity environment (35 degrees) on the thermal transfer image receiving sheet prepared above. 80% RH) was allowed to stand for 3 hours without condensation, and a solid black image was printed under the environment, and the peeling sound generated at that time was subjected to sensory evaluation.
Evaluation criteria 5: No peeling sound was heard.
4: A slight peeling sound was heard at the time of printing the third color, but there was no practical problem.
3: A large peeling sound was heard at the time of printing the third color, and there was a problem in practical use.
2: A peeling sound was heard at the time of printing the 2nd color.
1: Could not print.

(2) Evaluation of moisture resistance and heat resistance Using the sublimation thermal transfer printer (manufactured by ALTECH ADS, model: MEGAPICEL III), a 0.5 mm wide linear image (black) is printed on the thermal transfer image-receiving sheet produced above. Although the product was stored in an environment of 60 ° C. Free and 40 ° C. and 90% for one week, the image blur was visually evaluated.
-Evaluation criteria 5: It was not blurred.
4: When I looked closely, the line was slightly blurred.
3: The line was clearly blurred.
2: The line was blurred due to blurring.
1: The line was completely blurred and could not be confirmed as the original line.

(3) Adhesion Evaluation A 12-mm width industrial mending tape (manufactured by Nichiban Co., Ltd.) was attached to the thermal transfer image-receiving sheet prepared above, and a 90-degree peel test was performed. The evaluation criteria of the tape adhesion test are as follows.
Evaluation criteria 5: No destruction was observed on the thermal transfer image-receiving sheet, and no adhesion was observed on the mending tape.
4: Although no breakage was observed in the thermal transfer image-receiving sheet, a very small amount of coloring matter was adhered in the microscopic observation of the mending tape.
3: The thermal transfer image-receiving sheet was broken, and a layer having an area of less than 20% of the entire sticking area was adhered to the mending tape.
2: The thermal transfer image-receiving sheet was broken, and a layer having an area of 20% or more and less than 50% of the entire pasting area was adhered to the mending tape.
1: The thermal transfer image-receiving sheet was destroyed, and a layer having an area of 50% or more of the entire sticking region was adhered to the mending tape.

(4) Image density evaluation A sublimation type thermal transfer printer (manufactured by ALTECH ADS, model: MEGAPIXEL III) and an ink ribbon (for Megapixel III, Altech AD Co., Ltd. genuine product) are applied to the thermal transfer image receiving sheet prepared above. Using this, an 18 gradation gradation image having an RGB value of 15 × n (n = 0 to 17) is printed, and the optical reflection density by an optical densitometer (spectrolino manufactured by Gretag Macbeth) (Ansi-A, D65)) The maximum value was measured, and the OD value (optical density) of black was evaluated according to the following criteria.
Evaluation criteria ○: 2.0 or more Δ: 1.95 or more and less than 2.0 ×: less than 1.95

Table 2 shows the results of the above evaluations. The thermal transfer image-receiving sheets of Examples 1 to 11 satisfying the composition of the present invention were compared with the thermal transfer image-receiving sheets of Comparative Examples 1 to 3 and 5 to 6, and the releasability, moisture resistance / heat resistance and adhesion of the printed matter. It can be seen that each performance of image density and image density was improved.

10 Thermal transfer image receiving sheet 11 Base material 12 Heat insulation layer (lower layer)
13 Heat insulation layer (upper layer)
14 Primer layer 15 Intermediate layer 16 Receiving layer

Claims (12)

A thermal transfer image-receiving sheet comprising a base material, a heat insulating layer, an intermediate layer, and a receiving layer in this order on the base material,
The heat insulating layer comprises hollow particles;
The intermediate layer comprises a vinyl chloride resin and gelatin.
The receptor layer comprises a binder resin and a silicone release agent, and the gelatin content in the receptor layer is 1% by mass or less based on the solid content mass of the binder resin ;
A thermal transfer image-receiving sheet, wherein the silicone release agent comprises an epoxy-modified silicone having a viscosity of 100 to 10000 mm ² / s and an epoxy equivalent of 50 to 2000.   The thermal transfer image receiving sheet according to claim 1, wherein the binder resin contained in the receiving layer is a vinyl chloride resin.   The thermal transfer image-receiving sheet according to claim 1 or 2, wherein the binder resin contained in the receiving layer is a vinyl acetate resin.   The thermal transfer image-receiving sheet according to any one of claims 1 to 3, wherein the heat insulating layer and / or the receiving layer comprises an epoxy crosslinking agent.   The thermal transfer image receiving sheet according to any one of claims 1 to 4, further comprising a primer layer between the heat insulating layer and the receiving layer.   The thermal transfer image receiving sheet according to any one of claims 1 to 5, wherein all layers constituting the receiving layer from the heat insulating layer are formed by an aqueous coating method and a simultaneous multilayer coating method. A method for producing a thermal transfer image receiving sheet, comprising a base material, and a heat insulating layer, an intermediate layer, and a receiving layer in this order on the base material,
Using an aqueous coating solution containing hollow particles, forming a heat insulating layer on the substrate;
A step of forming an intermediate layer on the heat insulating layer using a coating solution containing a vinyl chloride-based resin and gelatin;
An aqueous dispersion in which a binder resin is dispersed and an aqueous dispersion in which a silicone release agent is dispersed and the gelatin content is 1% by mass or less based on the solid content mass of the binder resin are mixed. Forming a receptor layer on the intermediate layer using the aqueous dispersion coating solution obtained as described above,
A method for producing a thermal transfer image-receiving sheet, wherein the silicone release agent comprises an epoxy-modified silicone having a viscosity of 100 to 10,000 mm ² / s and an epoxy equivalent of 50 to 2000.   The manufacturing method of the thermal transfer image receiving sheet of Claim 7 whose binder resin contained in the aqueous dispersion coating liquid which forms the said receiving layer is a vinyl chloride resin.   The manufacturing method of the thermal transfer image receiving sheet of Claim 7 or 8 whose binder resin contained in the aqueous dispersion coating liquid which forms the said receiving layer is a vinyl acetate resin.   The thermal transfer image-receiving sheet according to any one of claims 7 to 9, wherein the aqueous coating solution forming the heat insulating layer and / or the aqueous dispersion coating solution forming the receiving layer further comprises an epoxy crosslinking agent. Production method. The thermal transfer image receiving sheet according to any one of claims 7 to 10, further comprising a step of forming a primer layer between the step of forming the heat insulating layer and the step of forming the receiving layer. Production method.   The manufacturing method of the thermal transfer image receiving sheet as described in any one of Claims 7-11 which forms all the layers which comprise the said receiving layer from the said heat insulation layer with a water-system application | coating and a simultaneous multilayer coating system.

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