Combination of thermal transfer sheet and intermediate transfer medium

Abstract

To provide a combination of a thermal transfer sheet and an intermediate transfer medium in which when a thermal transfer image is formed on an intermediate transfer medium using a thermal transfer sheet, when peeling the thermal transfer sheet and the intermediate transfer medium after adhesion, peeling force between each layer constituting the intermediate transfer medium is appropriate.SOLUTION: A combination of the thermal transfer sheet and the intermediate transfer medium disclosed herein includes a thermal transfer sheet comprising a substrate and a color material layer, and an intermediate transfer medium comprising a release member and a transfer sheet. The transfer sheet has, in order from the release member side, a protective substrate and a transfer layer. The release member has, in order from the transfer sheet side, a release layer, an adhesive layer, and a liner substrate. A slit extending from the surface of the transfer sheet opposite the release member side through the transfer sheet to the release member is provided. A region of the transfer sheet defined by the slit as its outer circumference can be transferred as a patch onto a target medium. When the patch is peeled from the release member at an angle of 90° at 70°C, the peeling force between the protective substrate and the release layer is 10 gf / cm or less, and when the patch is peeled from the release member at an angle of 90° at 25°C, the peeling force between the protective substrate and the release layer is greater than the peeling force between the color material layer and the transfer layer when the thermal transfer sheet is peeled from the transfer sheet during thermal transfer image formation.SELECTED DRAWING: None

Description

[Technical Field]

[0001] The present invention relates to a combination of a thermal transfer sheet and an intermediate transfer medium. [Background technology]

[0002] Various thermal transfer methods are known in which a thermal transfer sheet having a colored transfer layer formed on a substrate sheet is heated from the back surface of the sheet in an imagewise manner using a thermal head or the like, and the colored transfer layer is thermally transferred onto the surface of a thermal transfer image-receiving sheet to form an image. This thermal transfer method makes it possible to form a full-color image. For example, three or four-color thermal transfer sheets (yellow, magenta, cyan, and, if necessary, black) are prepared, and images of each color are thermally transferred onto the surface of the same thermal transfer image-receiving sheet in superimposed layers, thereby forming a full-color image. The specific uses of thermal transfer image-receiving sheets produced by this thermal transfer method are diverse.

[0003] With the diversification of the applications of the thermal transfer image receiving sheet, there is an increasing demand for forming a thermal transfer image on any object. Usually, a dedicated thermal transfer image receiving sheet having a receiving layer on a substrate is used as the object on which the thermal transfer image is to be formed. However, when there are restrictions on the substrate, a method has been proposed in which an intermediate transfer medium having a receiving layer releasably provided on the substrate, a thermal transfer sheet having a dye layer on the receiving layer, is used to transfer the dye to form an image, and then the intermediate transfer medium is heated to transfer the receiving layer onto any object to be transferred.

[0004] Patent Document 1 discloses a technology for forming a thermal transfer image on any object using an intermediate transfer medium. Specifically, the intermediate transfer medium is disclosed in which a sheet substrate provided with a resin layer and a release layer is laminated with a transparent sheet provided with an adhesive layer, and peeling occurs between the release layer and the transparent sheet, resulting in the transparent sheet with the adhesive layer being transferred to the transfer recipient. The intermediate transfer medium disclosed in Patent Document 1 uses a specific cellulose resin in the release layer, which prevents the transparent sheet from thermally fusing with the transfer recipient when it is transferred to the transfer recipient.

[0005] Furthermore, when it comes to ID cards and credit cards, which are objects on which thermal transfer images are formed, it is required to form the image over as much of the entire card surface as possible to minimize the margins around the outer edges, and to properly protect the image by forming a protective layer or the like.

[0006] Patent Document 2 discloses an intermediate transfer medium capable of forming a thermal transfer image with reduced margins on the outer edge of a transferee (sometimes referred to as "edge-to-edge printing"). The intermediate transfer medium disclosed in Patent Document 2 includes a transfer sheet that can be peeled off from a release member. The transfer sheet has, from the release member side, a protective substrate and a transfer layer, in that order. A slit is provided from the surface of the transfer sheet, penetrating the transfer sheet to the release member, and an area of ​​the transfer sheet defined by the slit as the periphery can be transferred as a patch to a transferee. Furthermore, the transfer sheet has, from the protective substrate side, a release layer, a protective layer, and a receiving layer.

[0007] When the intermediate transfer medium disclosed in Patent Document 2 is brought into close contact with a transferee and then peeled off, in the transfer area within the patch frame, peeling occurs at the interface between the release member and the transfer sheet. As a result, the transfer sheet is protected by the protective substrate within the patch frame. In contrast, in the transfer area outside the patch frame (the outer edge of the patch), peeling occurs at the interface between the protective substrate and the transfer layer of the transfer sheet (i.e., the interface between the protective substrate and the release layer). Therefore, by using this intermediate transfer medium, a printed product with little margin at the outer edge can be obtained. [Prior art documents] [Patent documents]

[0008] [Patent Document 1] Patent No. 5115224 [Patent Document 2] Japanese Patent Publication No. 2020-163781 Summary of the Invention [Problem to be solved by the invention]

[0009] According to the intermediate transfer medium disclosed in Patent Documents 1 and 2, the intermediate transfer medium and the transferee are brought into close contact with each other, and a transparent sheet or transfer sheet (patch) containing a thermally transferred image is transferred to the transferee, and then the patch can be easily peeled off between the patch and the release layer.

[0010] However, with the intermediate transfer media disclosed in Patent Documents 1 and 2, when a thermal transfer image is formed on the intermediate transfer medium using a thermal transfer sheet, there was a problem in that sufficient consideration had not been given to the peel force between the thermal transfer sheet and the receiving layer or peel layer that constitutes the intermediate transfer medium, and the peel force between the transfer sheet (patch) that constitutes the intermediate transfer medium and the peel layer when the thermal transfer sheet and the intermediate transfer medium are brought into close contact and then peeled off from each other.

[0011] The present disclosure has been made in consideration of the above circumstances, and aims to provide a combination of a thermal transfer sheet and an intermediate transfer medium in which, when a thermal transfer image is formed on an intermediate transfer medium using a thermal transfer sheet, the peel force between the thermal transfer sheet and the receiving layer or peel layer constituting the intermediate transfer medium, and the peel force between the transfer sheet (patch) constituting the intermediate transfer medium and the peel layer are appropriate when the thermal transfer sheet and the intermediate transfer medium are brought into close contact and then peeled off. [Means for solving the problem]

[0012] The combination of a thermal transfer sheet and an intermediate transfer medium of the present disclosure comprises a thermal transfer sheet having a substrate and at least one colorant layer, a release member, and an intermediate transfer medium having a transfer sheet laminated on the release member, wherein the transfer sheet has, from the release member side, a protective substrate and a transfer layer, in this order, and the release member has, from the transfer sheet side, a release layer, an adhesive layer, and a liner substrate, in this order, and a slit is provided on the surface of the transfer sheet opposite the release member side, penetrating the transfer sheet to the release member, and an area of ​​the transfer sheet defined by the slit as an outer periphery can be transferred to a transferee as a patch, and when the patch is peeled from the release member at an angle of 90° at 70°C, the peel force between the protective substrate and the release layer is 10 gf / cm or less, and when the patch is peeled from the release member at an angle of 90° at 25°C, the peel force between the protective substrate and the release layer is greater than the peel force between the colorant layer and the transfer layer when the thermal transfer sheet is peeled from the transfer sheet. [Effects of the Invention]

[0013] According to the present disclosure, when a thermal transfer image is formed on an intermediate transfer medium using a thermal transfer sheet, when the thermal transfer sheet and the intermediate transfer medium are brought into close contact and then peeled off, it is possible to provide the peel force between the thermal transfer sheet and the receiving layer or peel layer that constitutes the intermediate transfer medium, the peel force between the transfer sheet (patch) that constitutes the intermediate transfer medium and the peel layer, and the combination of the thermal transfer sheet and the intermediate transfer medium. [Brief explanation of the drawings]

[0014] [Figure 1] FIG. 1 is a schematic cross-sectional view showing one embodiment of the intermediate transfer medium of the present disclosure. [Figure 2] FIG. 2 is a diagram showing an embodiment of a method for producing a print according to the present disclosure. [Figure 3] FIG. 3 is a diagram showing an embodiment of a method for producing a print according to the present disclosure. [Figure 4] FIG. 4 is a diagram showing an embodiment of a method for producing a print according to the present disclosure. [Figure 5]FIG. 5 is a schematic cross-sectional view showing one embodiment of the intermediate transfer medium of the present disclosure. [Figure 6] FIG. 6 is a diagram showing an embodiment of a method for producing a print according to the present disclosure. [Figure 7] FIG. 7 is a diagram showing an embodiment of a method for producing a print according to the present disclosure. [Figure 8] FIG. 8 is a diagram showing an embodiment of a method for producing a print according to the present disclosure. DETAILED DESCRIPTION OF THE INVENTION

[0015] [Combination of thermal transfer sheet and intermediate transfer medium] The thermal transfer sheet and intermediate transfer medium combination of the present disclosure comprises a thermal transfer sheet and an intermediate transfer medium. The thermal transfer sheet comprises a substrate and at least one colorant layer. The intermediate transfer medium includes a release member and a transfer sheet laminated on the release member. The transfer sheet has a protective substrate and a transfer layer in this order from the release member side. The release member has, from the transfer sheet side, a release layer, an adhesive layer, and a liner substrate in this order. The intermediate transfer medium has a slit that runs from the surface of the transfer sheet opposite the release member side through the transfer sheet to the release member, and an area of ​​the transfer sheet defined by the slit as its outer periphery can be transferred as a patch to a transfer target. Hereinafter, a more detailed description will be given of preferred embodiments of the combination of the thermal transfer sheet and intermediate transfer medium of the present disclosure.

[0016] [Intermediate transfer medium] Fig. 1 is a cross-sectional view showing one embodiment of an intermediate transfer medium according to the present disclosure. In Fig. 1, the intermediate transfer medium 100 includes a release member 10 and a transfer sheet 20 disposed on the release member 10. The transfer sheet 20 includes a protective substrate 21, a primer layer 22, an intermediate layer 23, and a receiving layer 24, in this order from the release member 10 side in the thickness direction of the intermediate transfer medium 100. The primer layer 22, the intermediate layer 23, and the receiving layer 24 form a transfer layer. The receiving layer 24 forms the surface of the transfer layer.

[0017] The release member 10 includes a liner substrate 11, an adhesive layer 12, and a release layer 13 in this order in the thickness direction of the intermediate transfer medium 1, from the side opposite to the transfer sheet 20.

[0018] The intermediate transfer medium 100 of the present disclosure has a slit S that runs from the surface of the transfer sheet 20 opposite the release member 10 through the transfer sheet 20 to the surface of the release member 10, and an area of ​​the transfer sheet 20 defined by the slit S as its outer periphery can be transferred as a patch to the transferee P (see Figure 5). Hereinafter, each layer included in the intermediate transfer medium of the present disclosure will be described.

[0019] <Release material> (liner substrate) The liner substrate can be used without any particular restrictions as long as it has heat resistance to the thermal energy applied during thermal transfer and has the mechanical strength to support a transfer sheet or the like placed on a release member including the liner substrate.

[0020] The liner substrate can be, for example, a film made of a resin material (hereinafter also referred to as a "resin film"). Examples of the resin material include polyesters such as polyethylene terephthalate, polybutylene terephthalate, polyethylene naphthalate, 1,4-polycyclohexylene dimethylene terephthalate, and terephthalic acid-cyclohexanedimethanol-ethylene glycol copolymer; polyamide; polyimide; polycarbonate; polyolefins such as polyethylene, polypropylene, and polymethylpentene; polystyrene; vinyl resins such as vinyl chloride resin, vinyl acetate resin, vinyl chloride-vinyl acetate copolymer, polyvinyl alcohol, and polyvinylpyrrolidone; vinyl acetal resins such as polyvinyl acetoacetal and polyvinyl butyral; (meth)acrylic resins such as poly(meth)acrylate; cellulose resins such as cellophane, cellulose acetate, nitrocellulose, cellulose acetate propionate, and cellulose acetate butyrate; and ionomers.

[0021] Among the above resin materials, polyester is preferred from the viewpoint of heat resistance and mechanical strength, polyethylene terephthalate (PET) and polyethylene naphthalate (PEN) are more preferred, and PET is even more preferred.

[0022] In the present disclosure, "(meth)acrylic" encompasses both "acrylic" and "methacrylic," and "(meth)acrylate" encompasses both "acrylate" and "methacrylate."

[0023] A resin film laminate may be used as the liner substrate, and the resin film laminate can be produced by, for example, dry lamination, wet lamination, or extrusion.

[0024] The resin film may be a stretched film or an unstretched film. From the viewpoint of strength, a stretched film that is uniaxially or biaxially stretched is preferred.

[0025] The liner substrate may be subjected to a surface treatment on the surface of the liner substrate facing the adhesive layer in order to enhance adhesion to the adhesive layer. Examples of surface treatment methods include corona discharge treatment, flame treatment, ozone treatment, ultraviolet treatment, radiation treatment, roughening treatment, chemical treatment, plasma treatment, low-temperature plasma treatment, primer treatment, and grafting treatment.

[0026] The thickness of the liner substrate is preferably 1 μm or more and 50 μm or less, more preferably 3 μm or more and 25 μm or less, which can improve, for example, the mechanical strength of the liner substrate and the transfer of thermal energy during thermal transfer.

[0027] (adhesive layer) In one embodiment, the intermediate transfer medium of the present disclosure includes an adhesive layer on the surface of the liner substrate facing the transfer sheet, which can improve adhesion between the liner substrate and the release layer of the release member.

[0028] The adhesive layer preferably contains a resin material. Examples of the resin material include (meth)acrylic resin, vinyl resin, polyolefin, polyester, polyurethane, epoxy resin, urea resin, melamine resin, and phenol resin. Among these, a resin material containing polyester polyol is preferred from the viewpoint of adhesion to the release layer described below. The adhesive layer can contain one or more resin materials.

[0029] The content of the resin material in the adhesive layer is preferably 70% by mass or more and 100% by mass or less, and more preferably 80% by mass or more and 100% by mass or less.

[0030] The adhesive layer may be a layer obtained by curing a resin material with a curing agent, such as an isocyanate compound, an aliphatic amine, a cyclic aliphatic amine, an aromatic amine, or an acid anhydride.

[0031] The thickness of the adhesive layer is preferably 0.1 μm or more and 10 μm or less, and more preferably 0.5 μm or more and 2 μm or less. The adhesive layer can be formed, for example, by dispersing or dissolving the above-described components in a suitable solvent to prepare a coating liquid, which is then applied to a liner substrate and dried. Examples of the application method include roll coating, reverse roll coating, gravure coating, reverse gravure coating, bar coating, and rod coating.

[0032] (peeling layer) In one embodiment, the intermediate transfer medium of the present disclosure includes a release layer on the surface of the release member facing the transfer sheet. The release layer is a layer that does not constitute the transfer sheet and remains on the release member when the transfer sheet is transferred onto the transfer recipient. By providing the release layer, the thermal transferability of the transfer sheet including the protective substrate and the transfer layer can be further improved.

[0033] The release layer preferably contains a resin material. Examples of resin materials include (meth)acrylic resin, melamine resin, polyol resin, cellulose resin, silicone resin, acetal resin, polyurethane, polyamide, and polyester. The release layer can contain one or more resin materials. Among these, from the viewpoint of achieving both good adhesion between the thermal transfer sheet and the release layer and good adhesion between the protective substrate and the release layer, it is preferable that the release layer contains two or more cellulose-based resin materials with different Tg and a vinyl chloride-vinyl acetate copolymer as the resin material.

[0034] The content of the resin material in the release layer is preferably 70% by mass or more and 99% by mass or less, and more preferably 80% by mass or more and 98% by mass or less.

[0035] The release layer preferably contains a release agent. Examples of the release agent include silicone oil, wax, fluorine compounds, phosphate ester compounds, higher fatty acid amide compounds, and metal soaps. The release layer can contain one or more types of release agents.

[0036] The content of the release agent in the peel layer is preferably 0.1% by mass to 10% by mass, more preferably 0.5% by mass to 5% by mass, which can further improve the thermal transferability of the transfer sheet.

[0037] The release layer may contain additives, such as fillers, plasticizers, antistatic agents, UV absorbers, and dispersants. The release layer may contain one or more additives. The thickness of the release layer is preferably 0.1 μm or more and 5 μm or less.

[0038] The release layer can be formed, for example, by applying a coating liquid obtained by dispersing or dissolving the components described above in an appropriate solvent onto an adhesive layer provided on a liner substrate using the known coating method described above, and drying the coating liquid.

[0039] (back layer) In one embodiment, the intermediate transfer medium of the present disclosure may have a backing layer on the surface of the release member opposite to the surface on which the transfer sheet is provided (i.e., on the surface of the liner substrate opposite to the surface on which the adhesive layer is provided), which can suppress sticking and wrinkles caused by heat during thermal transfer.

[0040] The back layer preferably contains a resin material. Examples of the resin material include (meth)acrylic resin, styrene resin, vinyl resin, cellulose resin, polyester, polyurethane, polyvinyl acetal, silicone-modified polyurethane, and fluorine-modified polyurethane. The back layer can contain one or more resin materials.

[0041] The back layer may contain additives such as release agents such as silicone oil, wax, fluorine compounds, phosphate ester compounds, higher fatty acid amide compounds, and metal soaps; curing agents such as isocyanate compounds; organic particles such as fluorine resins; and inorganic particles such as silica, clay, talc, and calcium carbonate. This improves the slip properties of the back layer. The back layer may contain one or more additives.

[0042] The thickness of the back layer is preferably 0.01 μm to 5 μm, more preferably 0.03 μm to 2 μm, which can further suppress sticking and wrinkles while maintaining thermal energy transferability during thermal transfer.

[0043] The back layer can be formed, for example, by dispersing or dissolving the components described above in an appropriate solvent to prepare a coating liquid, which is then applied to a liner substrate by the known coating method described above and dried.

[0044] <Transfer sheet> (protective base material) The protective substrate can be any substrate without particular limitations as long as it has heat resistance to the thermal energy applied during thermal transfer and mechanical strength sufficient to protect the surface of the transfer layer to be transferred onto the transfer-receiving material.

[0045] As the protective substrate, a resin film similar to that described above for the liner substrate can be used.

[0046] The thickness of the protective substrate is not particularly limited, but is preferably from 0.5 μm to 100 μm, more preferably from 10 μm to 40 μm, which can improve, for example, the mechanical strength of the protective substrate and the transfer of thermal energy during thermal transfer.

[0047] (Primer layer) In one embodiment, the intermediate transfer medium of the present disclosure includes a primer layer on the surface of the protective substrate opposite the release member, which can improve adhesion between the protective substrate and the transfer layer in the transfer sheet.

[0048] The primer layer preferably contains a resin material. The resin material is not particularly limited as long as it can improve the adhesive strength between the protective substrate and the transfer layer. As such a resin material, those listed above for the adhesive layer can be used.

[0049] The thickness of the primer layer is preferably 0.1 μm or more and 10 μm or less, and more preferably 0.5 μm or more and 2 μm or less. The primer layer can be formed, for example, by dispersing or dissolving the components described above in an appropriate solvent to prepare a coating liquid, which is then applied to the protective substrate by the known coating method described above, and then dried.

[0050] (middle class) In one embodiment, the intermediate transfer medium of the present disclosure includes one or more intermediate layers between the primer layer and the receptor layer of the transfer sheet, which protect the receptor layer on which the thermally transferred image is formed.

[0051] The intermediate layer contains, as a resin material, one or more acrylic resins having a glass transition temperature (Tg) of 50° C. or higher. In one embodiment, the intermediate layer contains an acrylic resin with the above properties, which provides excellent cold adhesion to the receiving layer described below, and excellent patch adhesion to the receiving material when the patch is transferred to the receiving material.

[0052] Examples of the acrylic resin include BR64, BR87, BR119, MB7930, MB7931, MB7932, and MB7948 (manufactured by Mitsubishi Chemical Corporation).

[0053] The glass transition temperature (Tg) of the acrylic resin is preferably 50° C. or higher, more preferably 80° C. or higher, and in one embodiment, even more preferably 120° C. or higher. The upper limit of Tg is preferably 180° C. or lower. In the present disclosure, the glass transition temperature (Tg) is a value obtained by DSC in accordance with JIS K7121:1987.

[0054] In one embodiment, the acid value of the acrylic resin is preferably 15 mgKOH / g or more, more preferably 20 mgKOH / g or more. In the present disclosure, the acid value (mgKOH / g) is a value obtained in accordance with JIS K0070:1992.

[0055] The lower limit of the weight-average molecular weight (Mw) of the acrylic resin is preferably 10,000 or more, more preferably 15,000 or more, and even more preferably 20,000 or more. The upper limit is preferably 300,000 or less, more preferably 100,000 or less, and even more preferably 50,000 or less. When the lower limit of the weight-average molecular weight of the acrylic resin is 10,000 or more, in one embodiment, the patch has excellent adhesion to the transfer target when transferred to the transfer target. When the upper limit is 300,000 or less, coverage of the outer edge of the patch deteriorates. In this disclosure, the weight average molecular weight (Mw) is the average molecular weight measured by gel permeation chromatography (GPC) analysis and converted to standard polystyrene.

[0056] In one embodiment, the content of the acrylic resin in the entire resin material is preferably 70% by mass to 100% by mass, more preferably 80% by mass to 100% by mass, which can further improve the patch adhesion to the transfer recipient and, in one embodiment, can further improve the cold adhesion to the receiving layer described below.

[0057] In one embodiment, the intermediate layer may contain one or more resin materials other than the acrylic resin, such as polyester, polyurethane, polystyrene, (meth)acrylic resin, and (meth)acrylic polyol resin.

[0058] In one embodiment, the content of the resin material in the intermediate layer is preferably 80% by mass or more and 99% by mass or less, more preferably 85% by mass or more and 98% by mass or less, which can further improve the patch adhesion to the transfer recipient and the cold adhesion to the receiving layer described below.

[0059] In one embodiment, the intermediate layer preferably contains a release agent, which can improve the thermal transferability (releaseability) to the receiving layer described later in one embodiment.

[0060] Examples of the release agent include fluorine compounds, phosphate ester compounds, higher fatty acid amide compounds, metal soaps, silicone oils, and waxes such as polyethylene wax and paraffin wax.

[0061] Examples of silicone oils include straight silicone oils such as dimethyl silicone oil and methylphenyl silicone oil, as well as modified silicone oils such as amino-modified silicone oil, epoxy-modified silicone oil, carboxy-modified silicone oil, (meth)acrylic-modified silicone oil, mercapto-modified silicone oil, carbinol-modified silicone oil, fluorine-modified silicone oil, methylstyryl-modified silicone oil, and polyether-modified silicone oil. Modified silicone oils include single-end type, double-end type, and side-chain single-end type. The intermediate layer may contain one or more types of release agents.

[0062] The content of the release agent in the intermediate layer is preferably 0.5% by mass to 20% by mass, more preferably 0.5% by mass to 10% by mass, which can improve, for example, the thermal transferability.

[0063] The intermediate layer may contain one or more of the above additives. The content of the additive per 100 parts by mass of the resin material contained in the intermediate layer is preferably 0.1 parts by mass or more and 20 parts by mass or less, more preferably 0.5 parts by mass or more and 10 parts by mass or less.

[0064] The thickness of the intermediate layer is preferably 0.5 μm or more and 20 μm or less, more preferably 1 μm or more and 10 μm or less, which can further improve the cold adhesion to the receiving layer described below. The intermediate layer may have a single layer structure or a multi-layer structure of two or more layers.

[0065] The intermediate layer can be formed, for example, by dispersing or dissolving the components described above in a suitable solvent to prepare a coating liquid, which is then applied onto the primer layer by the known coating method described above, and then dried.

[0066] (receptor layer) In one embodiment, the intermediate transfer medium of the present disclosure includes a receptor layer on the surface of the intermediate layer of the transfer sheet. The receptor layer constitutes a surface layer on one side of the intermediate transfer medium.

[0067] The receiving layer contains one or more vinyl chloride-vinyl acetate copolymers as a resin material. By containing the vinyl chloride-vinyl acetate copolymer, the receiving layer has excellent cold adhesion with the intermediate layer, and when the patch is transferred to the transferee, the patch has excellent adhesion to the transferee. In other words, the receiving layer has excellent cold adhesion to the transferee.

[0068] Specific examples of vinyl chloride-vinyl acetate copolymers include Solbin C, Solbin CL, Solbin CLL3, Solbin CN, Solbin CNL, Solbin C5R, and Solbin TA5R (manufactured by Nissin Chemical Industry Co., Ltd.).

[0069] In one embodiment, the content of vinyl chloride-vinyl acetate copolymer in the entire resin material is preferably 70% by mass or more and 100% by mass or less, more preferably 80% by mass or more and 100% by mass or less, which can further improve the cold adhesion between the intermediate layer and the transfer target.

[0070] In one embodiment, the receiving layer may contain one or more resin materials other than vinyl chloride-vinyl acetate copolymers, such as polyolefins (e.g., polyethylene and polypropylene), vinyl resins other than vinyl chloride-vinyl acetate copolymers (e.g., polyvinyl chloride and polyvinyl acetate), polyesters (e.g., polyethylene terephthalate and polyethylene naphthalate), polystyrene, (meth)acrylic resins, polyamides, polyimides, polycarbonates, polyurethanes, cellulose resins, and ionomer resins. The receiving layer can contain one or more of the above resin materials.

[0071] The content of the resin material in the receiving layer is preferably 80% by mass to 99% by mass, more preferably 85% by mass to 98% by mass, which can further improve the receptivity of, for example, sublimation dyes.

[0072] In one embodiment, the receiving layer preferably contains a release agent. This improves the thermal transferability (releaseability) from the intermediate layer. Furthermore, when a thermal transfer image is formed on the receiving layer, the releaseability from the thermal transfer sheet having a sublimation transfer colorant layer can be improved. The receiving layer may contain one or more of the release agents exemplified for the intermediate layer.

[0073] The content of the release agent in the receiving layer is preferably 0.5% by mass to 20% by mass, more preferably 0.5% by mass to 10% by mass, which can improve, for example, the thermal transferability and releasability.

[0074] The receiving layer may contain one or more of the additives described above. The content of the additive per 100 parts by mass of the resin material contained in the receiving layer is preferably 0.1 parts by mass to 20 parts by mass, more preferably 0.5 parts by mass to 10 parts by mass.

[0075] The thickness of the receiving layer is preferably 0.5 μm to 20 μm, more preferably 1 μm to 10 μm, which can improve the density of the image formed on the receiving layer and the transferability of the transfer sheet.

[0076] The receiving layer can be formed, for example, by dispersing or dissolving the components described above in a suitable solvent to prepare a coating liquid, which is then applied onto the intermediate layer by the known coating method described above, and then dried.

[0077] (patch) In one embodiment, the patch is a region of the transfer sheet defined by a slit that penetrates the transfer sheet and reaches the release member. When the intermediate transfer medium of the present disclosure is viewed in a plan view in the thickness direction, the shape of the patch is not particularly limited, but may be, for example, similar to the shape of the transfer area of ​​the transfer object (see FIG. 5). The area of ​​the patch is also not particularly limited, but is preferably smaller than the entire transfer area of ​​the transfer object, for example, so as to cover a portion slightly inside the transfer area of ​​the transfer object.

[0078] In one embodiment, the intermediate transfer medium of the present disclosure can form a patch on the transfer sheet of the intermediate transfer medium by a conventionally known method, for example, as described in the above-mentioned Patent Document 1.

[0079] [Thermal transfer sheet] 2 is a cross-sectional view showing one embodiment of a thermal transfer sheet according to the present disclosure. In FIG. 2, a thermal transfer sheet 200 according to the present disclosure includes a substrate 31 and at least one color material layer 32 (32Y, 32M, 32C, 32B). In one embodiment, the thermal transfer sheet has one or more colorant layers formed in face-sequential order on one surface of a substrate. By using the thermal transfer sheet of this embodiment, a thermal transfer image can be formed on the receptor layer of an intermediate transfer medium. Hereinafter, each layer included in the intermediate transfer medium of the present disclosure will be described.

[0080] <Base material> As the substrate, the same resin films as those explained above for the liner substrate and protective substrate can be used.

[0081] <Color layer> For example, when a thermal transfer image is formed by a sublimation thermal transfer method, the colorant layer is a sublimation transfer type colorant layer containing a sublimation dye and a binder resin.

[0082] The sublimation dye preferably has sufficient color density and does not discolor or fade due to light, heat, etc. Examples of such sublimation dyes include red dyes, yellow dyes, and blue dyes. The sublimation transfer colorant layer can contain one or more sublimation dyes. The content of the sublimation dye in the sublimation transfer colorant layer is preferably 5% by mass or more and 80% by mass or less, more preferably 10% by mass or more and 70% by mass or less.

[0083] Examples of binder resins in the sublimation transfer colorant layer include cellulose resins, vinyl resins, vinyl acetal resins, (meth)acrylic resins, polyurethanes, polyamides, polyimides, and polyesters. The sublimation transfer colorant layer can contain one or more binder resins. The content of the binder resin in the sublimation transfer colorant layer is preferably 20% by mass or more and 75% by mass or less, more preferably 30% by mass or more and 60% by mass or less.

[0084] The sublimation transfer colorant layer may be cured with a curing agent. Examples of the curing agent include epoxy resin, isocyanate, and carbodiimide. One or more types of curing agents may be used.

[0085] The sublimation transfer colorant layer may contain one or more types of inorganic particles and organic particles. Examples of inorganic particles include carbon black, silica, alumina, titanium dioxide, and molybdenum disulfide. Examples of organic particles include polyethylene particles.

[0086] The sublimation transfer colorant layer may contain one or more release agents. Examples of release agents include fluorine compounds, phosphate ester compounds, higher fatty acid amide compounds, metal soaps, silicone oils, and waxes such as polyethylene wax and paraffin wax. The content of the release agent in the sublimation transfer colorant layer is preferably 0.01% by mass or more and 3% by mass or less, more preferably 0.01% by mass or more and 1% by mass or less.

[0087] For example, when a thermal transfer image is formed by a melting type thermal transfer method, the color material layer is a melting type color material layer containing a colorant and a binder resin.

[0088] The colorant preferably has sufficient color density and does not discolor or fade due to light, heat, or the like. Examples include organic pigments, inorganic pigments, and dyes. The colorant color is not limited to cyan, magenta, yellow, or black, but may be any of a variety of colors. The melt-transfer colorant layer may contain one or more colorants. The content of the colorant in the melt-transfer colorant layer is preferably 10% by mass or more and 60% by mass or less, more preferably 20% by mass or more and 50% by mass or less.

[0089] Examples of binder resins in the melt-transfer colorant layer include polyolefins, vinyl resins, vinyl acetal resins, (meth)acrylic resins, polystyrene, polycarbonate, cellulose resins, and petroleum resins. The melt-transfer colorant layer can contain one or more binder resins. The content of the binder resin in the melt-transfer colorant layer is preferably 20% by mass or more and 75% by mass or less, more preferably 30% by mass or more and 60% by mass or less.

[0090] The melt transfer colorant layer may further contain a conventionally known wax. The colorant layer may contain one or more of the above additives.

[0091] The thermal transfer sheet of the present disclosure may have one colorant layer on one side of the substrate, or may have multiple colorant layers of different hues, such as a yellow colorant layer (32Y), a magenta colorant layer (32M), a cyan colorant layer (32C), and a black colorant layer (32B), arranged in face sequence. The thickness of the colorant layer is preferably 0.1 μm or more and 5 μm or less.

[0092] The thermal transfer sheet of the present disclosure may be provided with a glittering material layer having an interference color and an adhesive layer after the coloring material layer. The adhesive layer is a layer for adhering the image pattern to the transfer surface of the information recording medium when the image pattern, which is composed of the coloring material image pattern and the glittering material image pattern transferred to the intermediate transfer medium in the primary transfer step, is retransferred to the information recording medium in the secondary transfer step.

[0093] [Manufacturing method for prints] The method for producing a print product of the present disclosure uses a combination of the thermal transfer sheet of the present disclosure and an intermediate transfer medium. Specifically, the thermal transfer sheet of the present disclosure is used to form a thermal transfer image on the receptor layer of the intermediate transfer medium of the present disclosure, and the patch is then transferred from the intermediate transfer medium to the transfer area of ​​a transfer recipient.

[0094] <Preparation process> The method for producing a print of the present disclosure may include a preparation step of preparing the thermal transfer sheet and intermediate transfer medium of the present disclosure, and a transfer-receiving body. The details of the thermal transfer sheet and intermediate transfer medium of the present disclosure are as described above.

[0095] (Transferred object) In the present disclosure, examples of the transfer object include metal plates such as aluminum plates, ceramic plates such as pottery, wood, glass substrates, paper substrates such as plain paper, fine paper, and tracing paper, and resin plates or resin films made of resin materials such as polycarbonate, polyester, (meth)acrylic resin, acrylonitrile-butadiene-styrene (ABS) copolymer resin, and polyvinyl chloride. Among these, resin cards such as polycarbonate and polyvinyl chloride are preferred.

[0096] In a preparation step, a thermal transfer image is formed on the receptor layer of the intermediate transfer medium of the present disclosure (hereinafter also referred to as an "image forming step").

[0097] Specifically, in the image formation process, an intermediate transfer medium having a receiving layer and a thermal transfer sheet having a colorant layer are superimposed so that the receiving layer and the colorant layer face each other, and the thermal transfer sheet is heated from the back side using a heating means such as a thermal head to transfer the sublimation dye contained in the sublimation transfer colorant layer to the receiving layer, or by transferring the melt transfer colorant layer onto the receiving layer (primary transfer), thereby forming a thermal transfer image.

[0098] In the image forming process, as described above, a thermal transfer image may be formed on the receiving layer of the intermediate transfer medium using the thermal transfer sheet of the present disclosure, in which one or more colorant layers are arranged in face-sequential order on one side of the substrate layer.

[0099] <Integration process (transfer process)> The integrating step is a step of integrating the intermediate transfer medium and the transferee so that the receptor layer on which the thermally transferred image is formed contacts the transfer area of ​​the transferee. This step produces a laminate having the transferee, the transfer layer, the protective substrate, and the release member in this order in the thickness direction.

[0100] The transfer step is a step in which the laminate obtained in the integration step is heated from the back side of the intermediate transfer medium using a heat roller or the like, and the transfer layer including the receptor layer on which the thermal transfer image is formed is transferred (secondary transfer) together with the protective substrate to the transfer area of ​​the transferee. Here, by using the intermediate transfer medium of the present disclosure, during transfer, peeling occurs at the interface between the transfer sheet and the release layer in the patch area, and peeling occurs at the interface between the protective substrate and the primer layer in the transfer area outside the patch. Therefore, in this step, the patch is transferred to the transfer area of ​​the transferee, and a printed product is obtained in which a laminate consisting of the receptor layer, intermediate layer, and primer layer is transferred to the transfer area outside the patch.

[0101] 3 to 6 show an outline of a method for producing a print according to one embodiment. First, as shown in Figure 3, in the image forming process, the thermal transfer sheet 200 and the intermediate transfer medium 100 are superimposed so that the receiving layer 24 and the color material layer 32 (magenta color material layer 32M) face each other, and a thermal head TH is used to heat the thermal transfer sheet from the back side, thereby transferring the sublimation dye contained in the sublimation transfer type color material layer to the receiving layer, or by transferring the melt transfer type color material layer onto the receiving layer, thereby forming a thermal transfer image.

[0102] Next, as shown in Fig. 4, the intermediate transfer medium 100 and the transferee P are bonded together so that the receptor layer 24 of the intermediate transfer medium 100 is in contact with one surface of the transferee P that will be the transfer area, and the intermediate transfer medium is heated from the back side with a heat roller or the like. At this time, as shown in Fig. 5, when viewed in plan from the stacking direction of the intermediate transfer medium 100 and the transferee P, it is preferable to align the intermediate transfer medium 100 so that the patch made of the transfer sheet defined by the slit S provided in the intermediate transfer medium 100 fits inside one surface (transfer area) of the transferee P. Note that alignment can be performed by a conventionally known method.

[0103] 6, the intermediate transfer medium 100 is peeled off from the transferee P, and a patch made of the transfer sheet 20 is transferred to one surface (transfer area) of the transferee P, and a laminate made of the receiving layer 24, intermediate layer 23, and primer layer 22 is transferred to the transfer area outside the patch. In this way, a printed object 300 is obtained.

[0104] [Prints] The printed matter of the present disclosure includes a transferee and a patch laminated on a transfer area of ​​the transferee. The patch has, from the transferee side, a transfer layer and a protective substrate, in this order. The transfer layer has, from the transferee side, at least a receiving layer on which a thermal transfer image is formed and an intermediate layer in contact with the receiving layer. A laminate consisting of the receiving layer, the intermediate layer, and a primer layer is laminated on the transfer area outside the patch.

[0105] FIG. 6 shows an example of the configuration of a print according to an embodiment. 6, in the printed matter 300 of the present disclosure, a patch made of a transfer sheet is laminated on one surface (transfer area) of a recipient P, and a laminate made of a receiving layer 24, an intermediate layer 23, and a primer layer 22 is laminated in the transfer area outside the patch. The printed matter 100 of the present disclosure has excellent adhesion between the recipient P and the patch, and the transfer area of ​​the recipient P is appropriately covered by the patch and the laminate made of the receiving layer 24, the intermediate layer 23, and the primer layer 22 transferred to the outer edge of the patch.

[0106] (Combination of thermal transfer sheet and intermediate transfer medium) In the combination of the thermal transfer sheet and intermediate transfer medium of the present disclosure, the peel force f1 between the protective substrate (reference numeral 21 in FIG. 6) and the release layer (reference numeral 13 in FIG. 6) when the patch is peeled from the release member at an angle of 90° at 70°C (i.e., in a state where the patch has been sufficiently heated by a heat roller or the like during secondary transfer) is 10 gf / cm or less. This allows smooth peeling between the protective substrate and the release layer when the transfer layer, which includes a receptor layer on which a thermal transfer image has been formed, is transferred together with the protective substrate to the transfer area of ​​the transfer recipient. The peel force f1 is preferably 6 gf / cm or less, and more preferably 4 gf / cm or less.

[0107] Furthermore, in the combination of the thermal transfer sheet and intermediate transfer medium of the present disclosure, the peel force f2 between the protective substrate (reference numeral 21 in FIG. 3) and the release layer (reference numeral 13 in FIG. 3) when the patch is peeled from the release member at an angle of 90° at 25°C (i.e., after being heated for a short time by a thermal head or the like during primary transfer) is greater than the peel force f3 between the colorant layer and the transfer layer (reference numeral 20 in FIG. 3) when the thermal transfer sheet is peeled from the transfer sheet during thermal transfer image formation (i.e., during primary transfer). This prevents peeling between the protective substrate and the release layer in the patch area of ​​the intermediate transfer medium when the thermal transfer sheet and the intermediate transfer medium are peeled off after a thermal transfer image is formed by overlapping the thermal transfer sheet and the intermediate transfer medium and using a heating means such as a thermal head to transfer the sublimation dye contained in the sublimation transfer colorant layer to the receptor layer or by transferring the melt transfer colorant layer onto the receptor layer.

[0108] The peel force f2 is preferably 3 gf / cm or more, and more preferably 5 gf / cm or more.

[0109] Moreover, in one embodiment, the above-mentioned peel force f3 is the peel force between the magenta colorant layer (reference numeral 32M in FIG. 3) and the receiving layer (reference numeral 24 in FIG. 3). The peel force f3 is preferably 1.0 gf / cm or less, and more preferably 0.4 gf / cm or less.

[0110] [Other embodiments] In one embodiment of the combination of the thermal transfer sheet and intermediate transfer medium of the present disclosure, the intermediate transfer medium is removed from the transfer sheet outside the patch to expose the release member.

[0111] Figure 7 is a cross-sectional view showing one embodiment of the intermediate transfer medium of the present disclosure. In Figure 7, the intermediate transfer medium 110 includes a release member 10 and a transfer sheet 20 provided on the release member 10. The transfer sheet 20 includes a protective substrate 21, a primer layer 22, an intermediate layer 23, and a receiving layer 24, in this order from the release member 10 side in the thickness direction of the intermediate transfer medium 100. The primer layer 22, the intermediate layer 23, and the receiving layer 24 constitute the transfer sheet 20. The receiving layer 24 also constitutes the surface of the transfer sheet.

[0112] 7, the intermediate transfer medium 110 of the present disclosure has a slit S formed on the surface of the transfer sheet 20 opposite the release member 10, penetrating the transfer sheet 20 to the surface of the release member 10. Here, an area of ​​the transfer sheet 20 defined by the slit S as its outer periphery is transferable to a transferee P as a patch, and the remaining area is removed from the surface of the release member 10. As a result, when the intermediate transfer medium 110 of the present disclosure is viewed in a plane in the thickness direction, the surface of the release member 10 (i.e., the surface of the peel layer 13) is exposed outside the transfer sheet 20 remaining as a patch.

[0113] (Combination of thermal transfer sheet and intermediate transfer medium) In the combination of the thermal transfer sheet and intermediate transfer medium of the present disclosure, when the intermediate transfer medium 110 shown in FIG. 7 is used as the intermediate transfer medium, the peel force f1 is 10 gf / cm or less, and the peel force f2 is greater than the peel force f3.

[0114] When an intermediate transfer medium 110 is used, a thermal transfer sheet and the intermediate transfer medium are superimposed, and a heating device such as a thermal head is used to transfer the sublimation dye contained in the sublimation transfer colorant layer to the receptor layer, or to transfer the melt-transfer colorant layer onto the receptor layer, thereby forming a thermal transfer image. As shown in FIG. 8, the thermal transfer sheet 200 adheres to the area of ​​the intermediate transfer medium 110 where the transfer sheet 20 has been removed (i.e., the area where the release member 10 is exposed). Therefore, in one embodiment, the combination of the thermal transfer sheet and intermediate transfer medium of the present disclosure has a peel force f4 between the colorant layer and the release layer when the thermal transfer sheet is peeled from the release member of 55 gf / cm or less. This allows smooth peeling between the thermal transfer sheet and the intermediate transfer medium, even when the thermal transfer sheet adheres to the area of ​​the intermediate transfer medium where the transfer sheet has been removed (i.e., the exposed release member).

[0115] In one embodiment, the above-mentioned peel force f4 is the peel force between the magenta colorant layer (reference numeral 32M in FIG. 8) and the release layer (reference numeral 13 in FIG. 8). The above-mentioned peel force f4 is preferably 40 gf / cm or less, and more preferably 35 gf / cm or less.

[0116] The peel forces f1, f2, and f3 between the transfer sheet and the release layer in the intermediate transfer medium can be measured by a flat plate cross-stage method using a peel test device having the structure described in Japanese Patent No. 4717156.

[0117] The method for measuring the peel force f4 will be described later.

[0118] The present disclosure relates to, for example, the following [1] to [4]. [1] A thermal transfer sheet having a substrate and at least one colorant layer; an intermediate transfer medium including a release member and a transfer sheet laminated on the release member; the transfer sheet has a protective substrate and a transfer layer in this order from the release member side, the release member has, from the transfer sheet side, a release layer, an adhesive layer, and a liner substrate in this order; a slit is provided from the surface of the transfer sheet opposite to the release member side through the transfer sheet to the release member, A combination of a thermal transfer sheet and an intermediate transfer medium, in which an area of ​​the transfer sheet defined by the slit as an outer periphery can be transferred as a patch to a transfer-receiving body, the peel force between the protective substrate and the release layer when the patch is peeled from the release member at an angle of 90° at 70°C is 10 gf / cm or less; A combination of a thermal transfer sheet and an intermediate transfer medium, wherein at 25°C, when the patch is peeled from the release member at an angle of 90°, the peel force between the protective substrate and the release layer is greater than the peel force between the colorant layer and the transfer layer when the thermal transfer sheet is peeled from the transfer sheet. [2] The intermediate transfer medium has a region of the transfer sheet outside the patch removed to expose the release member, A combination of the thermal transfer sheet and intermediate transfer medium described in [1] above, wherein the hot peel force between the colorant layer and the peel layer when the thermal transfer sheet is peeled from the release member is 55 gf / cm or less. [3] A combination of the thermal transfer sheet described in [1] or [2] above and an intermediate transfer medium, wherein the transfer layer has at least a receiving layer located on the surface opposite the protective substrate and an intermediate layer in contact with the receiving layer. [4] A combination of the thermal transfer sheet according to any one of [1] to [3] above and an intermediate transfer medium, wherein the thermal transfer sheet has, as the colorant layers, at least a yellow colorant layer and a magenta colorant layer in face sequence. [Example]

[0119] Next, the combination of the thermal transfer sheet and intermediate transfer medium of the present disclosure will be described in more detail using examples, but the combination of the thermal transfer sheet and intermediate transfer medium of the present disclosure is not limited to these examples. In the following description, "parts" means "parts by mass." The blending amounts shown in the following description and Table 1 are values ​​converted to solids, excluding water and organic solvents.

[0120] [Preparation example] <Thermal transfer sheet> A 5 μm-thick polyethylene terephthalate film was used as the substrate. A dye primer layer coating liquid having the following composition was applied to a portion of one surface of the substrate to a dry thickness of 0.15 μm and dried to form a dye primer layer. Yellow, magenta, and cyan colorant layer coating liquids having the following compositions were applied to this dye primer layer in face-sequential order to a dry thickness of 0.7 μm and dried to form a yellow colorant layer, a magenta colorant layer, and a cyan colorant layer. Furthermore, a melt-ink layer having the following composition was applied to an area of ​​one surface of the substrate where the dye primer layer was not formed to a dry thickness of 0.7 μm and dried to form a melt-ink layer. A back layer coating liquid having the following composition was applied to the other surface of the substrate to a dry thickness of 1 μm and dried to form a back layer, thereby obtaining a thermal transfer sheet.

[0121] <Coating liquid for back layer> Polyvinyl butyral 1.8 parts (S-LEC (registered trademark) BX-1 Sekisui Chemical Co., Ltd.) Polyisocyanate 5.5 parts (Burnoc (registered trademark) D750 DIC Corporation) Phosphate ester surfactant 1.6 parts (Plysurf (registered trademark) A208N Daiichi Kogyo Seiyaku Co., Ltd.) Talc 0.35 parts (Micro Ace (registered trademark) P-3, Nippon Talc Industrial Co., Ltd.) Toluene 18.5 parts Methyl ethyl ketone 18.5 parts

[0122] <Coating liquid for dye primer layer> Colloidal alumina (solid content 10.5%) 3.5 parts (Alumina Sol 200, Nissan Chemical Industries, Ltd.) Vinyl acetate-vinylpyrrolidone copolymer 1.5 parts (PVP / VA E-335 ISP Japan Co., Ltd.) ·Wednesday 47.5 parts 47.5 parts isopropyl alcohol

[0123] <Coating liquid for yellow colorant layer> Solvent Yellow 93 2.5 parts Disperse Yellow 201 2.5 parts Polyvinyl acetal 4 parts (S-LEC (registered trademark) KS-5 Sekisui Chemical Co., Ltd.) Organically modified silicone oil 0.04 parts 50 parts toluene 50 parts methyl ethyl ketone

[0124] <Coating liquid for magenta colorant layer> 3 parts Disperse Red 60 3 parts Disperse Violet 26 Polyvinyl acetal 5 parts (S-LEC (registered trademark) KS-5 Sekisui Chemical Co., Ltd.) Organically modified silicone oil 0.05 parts 50 parts toluene 50 parts methyl ethyl ketone

[0125] <Coating liquid for cyan colorant layer> 3 parts Solvent Blue 63 Disperse Blue 354 4 parts Polyvinyl acetal 5 parts (S-LEC (registered trademark) KS-5 Sekisui Chemical Co., Ltd.) Organically modified silicone oil 0.05 parts 50 parts toluene 50 parts methyl ethyl ketone

[0126] <Coating liquid for melt ink layer> Carbon black 4 parts Vinyl chloride-vinyl acetate copolymer 6 parts (Solvine (registered trademark) CNL, Nissin Chemical Industry Co., Ltd.) 50 parts toluene 50 parts methyl ethyl ketone

[0127] <Intermediate transfer medium> Example 1 A 25 μm thick polyethylene terephthalate film (PET E-5100 Toyobo Co., Ltd.) was used as the liner substrate of the release member, and adhesive layer coating liquid 1 having the following composition was applied to the liner substrate so that the thickness when dried was 3 μm, and then dried to obtain a release member having an adhesive layer formed on the liner substrate.

[0128] <Coating liquid 1 for adhesive layer> Polyester polyol solution (50% solids) 54 parts (Seikabond E-295NTL-D50 Dainichiseika Color & Chemicals Mfg. Co., Ltd.) Polyisocyanate (100% solids) 6 parts (Seikabond C-55 Dainichi Seika Color & Chemicals Mfg. Co., Ltd.) 30 parts ethyl acetate

[0129] Furthermore, a 16 μm thick polyethylene terephthalate film (transparent PET E-5102, Toyobo Co., Ltd.) was used as the protective substrate, and primer layer coating liquid 1 having the following composition was applied to one side of the protective substrate so that the thickness when dried was 0.7 μm, and then dried to form a primer layer on the protective substrate.

[0130] Vinyl chloride-vinyl acetate copolymer 42 parts (Solvine (registered trademark) A, Nissin Chemical Industry Co., Ltd.) Polyester (Vylon (registered trademark) 200 Toyobo Co., Ltd.) 42 parts Isocyanate compound 16 parts (Mitsui Chemicals, Inc., Takenate (registered trademark) D110N, solid content 75%) 200 parts toluene 200 parts methyl ethyl ketone

[0131] Next, intermediate layer coating solution 1 having the following composition was applied onto the primer layer so as to have a dry thickness of 6.0 μm, and then dried to provide intermediate layer 1.

[0132] <Coating liquid 1 for forming intermediate layer> Acrylic resin (Dianal (registered trademark) BR-87 Mitsubishi Chemical Corporation) 100 parts 300 parts methyl ethyl ketone

[0133] Furthermore, a receiving layer was formed on the intermediate layer 1 by applying a coating liquid for the receiving layer having the following composition to a dry thickness of 3.0 μm and drying it. The primer layer, intermediate layer 1, and receiving layer constitute a transfer layer.

[0134] <Receptor layer coating solution 1> Vinyl chloride-vinyl acetate copolymer 100 parts (Solvine (registered trademark) CNL, Tg: 74°C, Mn: 16000) Epoxy-modified silicone oil 5 parts (Shin-Etsu Chemical Co., Ltd., product name: KP-1800U) 315 parts methyl ethyl ketone

[0135] Next, on the other surface of the protective substrate, Coating Solution 1 for release layer having the following composition was applied to a dry thickness of 2.0 μm and dried to form a release layer, thereby obtaining a laminated sheet in which the release layer, protective substrate, and transfer layer (primer layer, intermediate layer, and receiving layer) were laminated in this order.

[0136] <Release layer coating liquid 1> Cellulose resin 50 parts (CAP-482-20 manufactured by Eastman Chemical Co., Tg: 147°C, Mn: 75,000) Cellulose resin 40 parts (CAB-551-0.01 manufactured by Eastman Chemical Co., Tg: 85°C, Mn: 16,000) Vinyl chloride-vinyl acetate copolymer 10 parts (Solvine (registered trademark) CNL, Tg: 69°C, Mn: 16,000) 340 parts methyl ethyl ketone 340 parts toluene

[0137] Subsequently, the release member and the laminate sheet were bonded together so that the adhesive layer and the peeling layer faced each other, thereby obtaining an intermediate transfer medium in which the release member and the laminate sheet were integrated.

[0138] Next, continuous half-cut slits, slightly smaller in size than the card (specifications will be described later) that was the transfer target, were formed on the surface of the transfer sheet opposite the release member, extending to the surface on the release member side, and the transfer sheet outside the slits was removed to obtain the intermediate transfer medium of Example 1.

[0139] (Example 2, Comparative Examples 1 to 7) The coating liquid for forming each layer and the thickness of each layer were changed as shown in Table 1 below to obtain intermediate transfer media of Example 2 and Comparative Examples 1 to 7.

[0140] Example 3 The coating liquid for forming each layer and the thickness of each layer were changed as shown in Table 1 below, intermediate layer 2 was provided between intermediate layer 1 and the receiving layer, and continuous half-cut notches were formed from the surface of the transfer sheet opposite the release member to the surface on the release member side, thereby obtaining the intermediate transfer medium of Example 3.

[0141] [Table 1]

[0142] <Coating liquid 2 for adhesive layer> Polyurethane 63 parts (Takelac® A-969V(60S) (Mitsui Chemicals, Inc.)) Urethane, methylenebis(4,1-phenylene) diisocyanate 18 parts (Takenate (registered trademark) A-5 (Mitsui Chemicals, Inc.)) 30 parts ethyl acetate

[0143] <Release layer coating liquid 2> Cellulose resin 40 parts (CAP-482-20, Tg: 147℃, Mn: 75,000) Cellulose resin 40 parts (CAB-551-0.01, Tg:85℃, Mn:16,000) Vinyl chloride-vinyl acetate copolymer 20 parts (Solvine (registered trademark) CNL, Nissin Chemical Industry Co., Ltd., Tg: 69°C, Mn: 16,000) 340 parts methyl ethyl ketone 340 parts toluene

[0144] <Release layer coating solution 3> Cellulose resin 40 parts (CAP-482-20 manufactured by Eastman Chemical Co., Tg: 147°C, Mn: 75,000) Cellulose resin 40 parts (CAB-551-0.01 manufactured by Eastman Chemical Co., Tg: 85°C, Mn: 16,000) Vinyl chloride-vinyl acetate copolymer 20 parts (Solvine (registered trademark) CNL, Nissin Chemical Industry Co., Ltd., Tg: 69°C, Mn: 16,000) Polyester urethane 3 parts (UE4800 (Toyobo Co., Ltd.), Tg: 106°C, Mn: 25,000) 340 parts methyl ethyl ketone 340 parts toluene

[0145] <Release layer coating solution 4> Cellulose resin 100 parts (CAP B-20 Showa Ink Industrial Co., Ltd.) 340 parts methyl ethyl ketone 340 parts toluene

[0146] <Release layer coating liquid 5> CAP varnish 50 parts (CAP B-20 Showa Ink Industrial Co., Ltd.) Vinyl chloride-vinyl acetate copolymer 50 parts (Solvine (registered trademark) CNL, Nissin Chemical Industry Co., Ltd., Tg: 69°C, Mn: 16,000) 340 parts methyl ethyl ketone 340 parts toluene

[0147] <Release layer coating liquid 6> CAP varnish 60 parts (CAP B-20 Showa Ink Industrial Co., Ltd.) Vinyl chloride-vinyl acetate copolymer 30 parts (Solvine (registered trademark) CNL, Nissin Chemical Industry Co., Ltd., Tg: 69°C, Mn: 16,000) 10 parts polyethylene wax (Slip Agent B, Showa Ink Industries Co., Ltd.) 340 parts methyl ethyl ketone 340 parts toluene

[0148] <Release layer coating solution 7> CAP varnish 60 parts (CAP B-20 Showa Ink Industrial Co., Ltd.) Vinyl chloride-vinyl acetate copolymer 30 parts (Solvine (registered trademark) CNL, Tg: 69°C, Mn: 16,000) 10 parts polyethylene wax (Slip Agent B, Showa Ink Industries Co., Ltd.) 3 parts silicone (X-22-1660B-3 Dainichiseika Chemical Co., Ltd.) Filler (melamine formaldehyde condensate) 4 parts (Eposter S12, Nippon Shokubai Co., Ltd.) 340 parts methyl ethyl ketone 340 parts toluene

[0149] <Coating liquid 2 for forming intermediate layer> Vinyl chloride-vinyl acetate copolymer 100 parts (Solvine (registered trademark) CNL, Nissin Chemical Industry Co., Ltd., Tg: 69°C, Mn: 16,000)

[0150] <Coating liquid 1 for forming intermediate layer 2> 100 parts acrylic resin (Dianal (registered trademark) MB7948 Mitsubishi Chemical Corporation, Mw 25,000, Tg: 126°, acid value: 21 mg KOH / g)

[0151] [Evaluation method] <Peeling force between thermal transfer sheet and intermediate transfer medium under heat> The hot peeling force between the colorant layer of the thermal transfer sheet and the image receiving layer or peeling layer of the intermediate transfer medium was measured under the following conditions, and the results are shown in Table 2 below.

[0152] (Test equipment) Device name: Ultra-high speed SIP manufactured by Systems Intelligence Products (SIP) Thermal head voltage setting: 25V Printing speed: 2mm / sec Image: 16-level grayscale image from 0 to 255 (size: width 46mm x length 64mm)

[0153] (Sample for measuring hot peel strength) For the intermediate transfer media of Examples 1 to 3 and Comparative Examples 1 to 7, the following sheets were prepared as samples for measuring the peel strength under heat. - Sheet with exposed patch surface (receptor layer surface) - Sheets with the transfer sheet removed and the release layer exposed

[0154] (Measurement of hot peel strength) The thermal transfer sheet of the present invention was placed on a sample for measuring the peel strength under heat, and a printer equipped with a thermal transfer sheet supply means, a heating means, a thermal transfer sheet take-up means, a measuring means positioned between the heating means and the thermal transfer sheet take-up means to measure the tensile strength of the thermal transfer sheet transported along the transport path, and a peeling means positioned between the heating means and the measuring means was used to transfer the transfer layer onto a transfer recipient while peeling the transfer layer transferred onto the transfer recipient from the substrate under conditions of a printing power of 0.15 W / dot, a thermal transfer sheet transport speed of 84.6 mm / sec, and a peeling angle of 50°. The tensile strength measured by the measuring means was then measured. The measurement results are shown in Table 2.

[0155] <Peeling force between transfer sheet and release member in intermediate transfer medium> The peel force between the transfer sheet (protective substrate) and the release member (peeling layer) in the intermediate transfer medium of Examples 1 to 3 and Comparative Examples 1 to 7 was measured under the following conditions. The results are shown in Table 2 below.

[0156] (Test equipment) Measuring instrument: Peel analysis device VPA-3 (manufactured by Kyowa Interface Science Co., Ltd.) Measurement unit: 5N load cell Stage temperature: room temperature (25℃), 70℃ Peeling angle: 90° ·Speed: 300mm / min

[0157] (sample) The intermediate transfer media of Examples 1 to 3 and Comparative Examples 1 to 7 were prepared as samples. - Sheet with exposed patch surface (receptor layer surface) - Sheets with the transfer sheet removed and the release layer exposed

[0158] (Test Procedure) Cut the sample to a width of 4 cm and a length of 10 cm and attach it to the stage (stainless steel plate) with double-sided tape. Use 12mm cellophane tape to attach the peeling side of the sample (patch PET film) to the sample fixing plate fixed to the measurement unit. Make sure to apply the tape straight. When measuring the temperature at 70°C, heat the stage using the included temperature controller and use the included handheld thermometer to confirm that the sample surface temperature is 70°C. Start the device and measure the peel force, and record the average value as the peel force.

[0159] <Formation of thermal transfer image> Using the intermediate transfer media of Examples 1 to 3 and Comparative Examples 1 to 7 obtained above, the thermal transfer sheets obtained above, and the following test printer, a black image (image gradation: 0 / 255) was formed on the receiving layer of each intermediate transfer medium. The peelability between the thermal transfer sheet and the intermediate transfer medium during the formation of the thermal transfer image was evaluated based on the following evaluation criteria. The evaluation results are shown in Table 2 below.

[0160] (test printer) Thermal head: KEE-57-12GAN2-STA (Kyocera Corporation) Heating element average resistance: 3303 (Ω) Print density in the main scanning direction: 300 (dpi) Sub-scanning direction print density: 300 (dpi) Printing voltage: 18(V) Line period: 1.5 (msec. / line) Printing start temperature: 35(℃) Pulse duty ratio: 85(%)

[0161] (Evaluation Criteria 1) ◯: Separation is possible between the colorant layer of the thermal transfer sheet and the receptor layer of the intermediate transfer medium. x: The coloring material layer of the thermal transfer sheet cannot be separated from the receiving layer of the intermediate transfer medium.

[0162] (Evaluation Criteria 2) ◯: Separation is possible between the colorant layer of the thermal transfer sheet and the release layer of the intermediate transfer medium. x: The colorant layer of the thermal transfer sheet cannot be separated from the release layer of the intermediate transfer medium.

[0163] <Creating prints> Using an experimental heat roller, the transfer sheets (transfer layer and protective substrate) of the intermediate transfer media of Examples 1 to 3 and Comparative Examples 1 to 7 on which the above-described images had been formed were transferred onto a polyvinyl chloride card (approximately 54 mm long x 86 mm wide x 0.8 mm thick, Dai Nippon Printing Co., Ltd.) as a transfer recipient conforming to the JIS X 6301:2005 standard dimensions at 202°C and 20 mm / sec. to produce printed images, and the transferability of the patch to the transfer recipient was evaluated based on the following evaluation criteria. The evaluation results are also shown in Table 2.

[0164] (Experimental conditions) Heat roller rubber hardness: 60° Nip roller rubber hardness: 70° Distance between heat roller and nip roller during heating: 0 mm

[0165] (Evaluation Criteria 3) ◯: The transfer sheet is transferred to the transfer target. ×: The transfer sheet is not transferred to the transfer object.

[0166] [Table 2] [Explanation of symbols]

[0167] 100, 110: Intermediate transfer medium 10: Release material 11: Liner base material 12: Adhesion layer 13: Peel layer 20: Transfer sheet 21: Protective base material 22: Primer layer 23: Middle class 24: Receptor 200: Thermal transfer sheet 300: Prints S: Slit

Claims

1. a thermal transfer sheet including a substrate and at least one colorant layer; an intermediate transfer medium including a release member and a transfer sheet laminated on the release member; the transfer sheet has a protective substrate and a transfer layer in this order from the release member side, the release member has, from the transfer sheet side, a release layer, an adhesive layer, and a liner substrate in this order; a slit is provided from the surface of the transfer sheet opposite to the release member side through the transfer sheet to the release member, A combination of a thermal transfer sheet and an intermediate transfer medium, in which an area of ​​the transfer sheet defined by the slit as an outer periphery can be transferred as a patch to a transfer-receiving body, the peel force between the protective substrate and the release layer when the patch is peeled from the release member at an angle of 90° at 70°C is 10 gf / cm or less; A combination of a thermal transfer sheet and an intermediate transfer medium, wherein at 25°C, when the patch is peeled from the release member at an angle of 90°, the peel force between the protective substrate and the release layer is greater than the peel force between the colorant layer and the transfer layer when the thermal transfer sheet is peeled from the transfer sheet.

2. the intermediate transfer medium is formed by removing an area of ​​the transfer sheet outside the patch to expose the release member; 2. The combination of the thermal transfer sheet and intermediate transfer medium according to claim 1, wherein the thermal peel strength between the colorant layer and the release layer when the thermal transfer sheet is peeled from the release member is 55 gf / cm or less.

3. 3. The combination of the thermal transfer sheet and intermediate transfer medium according to claim 1, wherein the transfer layer has at least a receiving layer located on the surface opposite to the protective substrate, and an intermediate layer in contact with the receiving layer.

4. 3. The combination of the thermal transfer sheet and the intermediate transfer medium according to claim 1, wherein the thermal transfer sheet comprises, as the colorant layers, at least a yellow colorant layer and a magenta colorant layer arranged in face sequence.

Images