JP2003094846A - Thermal transfer film and manufacturing method therefor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a thermal transfer film which is excellent in the durability of an obtained thermal transfer print, including the abrasion resistance, light-resistance and forgery preventing properties, and which causes little damage on a transfer object and brings about neither deterioration of the quality of the print, nor a rise of the manufacturing cost. SOLUTION: In the thermal transfer film, a thermal transfer layer having a projecting part partially is formed on one side of a base, at the most distant position from the base, and by using this film, the thermal transfer layer is transferred onto the transfer object. On the occasion, it is possible to form an image beforehand on the object of transfer of the thermal transfer layer by a thermal transfer recording method or the like and to transfer the thermal transfer layer onto the image. In another way, it is possible to form a thermal transfer image by transferring a thermal transfer ink layer onto the thermal transfer layer of the thermal transfer film and to transfer the image together with the thermal transfer layer whereon it is formed. In either way, the image is protected by the thermal transfer layer and the projecting part of the thermal transfer layer transferred onto the transfer object can be distinguished by the reflection of light according to the angle of a glance to an image recording surface. A protective layer and the projecting part can be formed on the transfer object by one transfer.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a thermal transfer film in which a thermal transfer layer having a convex portion on one side is formed on a substrate at a position farthest from the substrate.

[0002]

2. Description of the Related Art The thermal transfer system is widely used for various purposes because it can record variable information easily. In this method, a thermal transfer film in which a color material layer is provided on a base material and a transfer target in which a receiving layer is provided as necessary are pressed between a heating device such as a thermal head and a platen roll. In this method, an image is recorded by selectively heating the heating portion of the heating device according to the image information and transferring the color material contained in the color material layer on the thermal transfer film to the transfer target. This method is roughly classified into a melt heat transfer method and a sublimation heat transfer method.

In the melt heat transfer system, a heat transfer film carrying a melted ink layer is heated by the above-mentioned heating means to transfer the softened melted ink layer component onto a transfer object such as natural fiber paper or a plastic sheet. Is a method of forming an image. The molten ink layer used here is a color material such as a pigment dispersed in a hot-melt wax or a binder such as a resin, and is carried on a substrate such as a plastic film. The formed image has high density and excellent sharpness, and is suitable for recording binary images such as characters and line drawings.

In the sublimation transfer system, a thermal transfer film carrying a sublimation dye layer is heated by the above-mentioned heating means to sublimate the sublimation dye contained in the dye layer to provide a receiving layer provided on a transfer target. It is a method of forming an image by shifting to. The sublimation dye used here is a sublimation dye used as a coloring material dissolved or dispersed in a binder resin, and is carried on a base film such as a plastic film. In this method, the amount of energy transferred to a heating device such as a thermal head can control the amount of dye transfer in dot units, so that gradation reproduction by density modulation is possible. As described above, the fusion heat transfer method can easily and clearly form images such as letters and numbers, and the sublimation transfer method is excellent in gradation expression and precisely and beautifully forms images such as facial photographs. Each of them has its own characteristics.

The image formed by the above-mentioned thermal transfer system has insufficient durability such as abrasion resistance, light resistance, tamper resistance, etc. in both of the melting thermal transfer system and the sublimation transfer system. In order to cope with this, a protective layer is formed on. For example, JP-A-3-15979
In Japanese Patent Laid-Open No. 5 (1994), information such as images and characters is formed on a card substrate, and a transparent protective layer is provided on the surface of at least a part of the information, and the protective layers are overlapped with each other, for example, at least two layers or more. Transferred differently, of which at least one protective layer contains a fluorescent whitening agent and / or an ultraviolet absorber. But with this method,
Since the transfer of the protective layer is performed twice or more on the transfer target (card), the transfer target is largely damaged, and there are many steps (transfer) until the print is obtained, which is troublesome and the print quality is high. Problems such as deterioration and increase in manufacturing cost are likely to occur.

Further, Japanese Patent Application Laid-Open No. 2000-177249 describes a recorded matter in which a color image is formed on a recording paper and a transparent image is formed on the color image by a transparent ink, and the color image and the transparent image are It is disclosed that an overcoat layer is formed between the two. As a result, the weather resistance and abrasion resistance of the color image can be improved, and the transparent image on the color image can be captured by the reflection of light according to the angle of the line of sight of the image with respect to the recording surface. Even in this case, since the transparent image and the overcoat layer are transferred multiple times on the color image on the recording paper, the damage to the transferred material is great and the process of obtaining the printed matter (transfer)
However, it is troublesome, and problems such as deterioration of print quality and increase of manufacturing cost are likely to occur.

[0007]

SUMMARY OF THE INVENTION Therefore, the present invention has been made in view of such problems, and the obtained thermal transfer prints have durability such as abrasion resistance, light resistance and tamper resistance. It is an object of the present invention to provide a thermal transfer film which is excellent in heat resistance, has less damage to the transferred material, and does not deteriorate the quality of the printed matter and increase the manufacturing cost.

[0008]

In order to achieve the above object, in the thermal transfer film of the present invention, a thermal transfer layer having a convex portion partially on one side of a substrate is formed at a position farthest from the substrate. It has a structure. The above-mentioned thermal transfer layer preferably contains a thermoplastic resin having a glass transition point of 50 to 120 ° C. as a main component, whereby the transferability and the fixability to the transfer target are good. The thermoplastic resin according to claim 2 is a polyester resin having a number average molecular weight of 2000 to 30000, a vinyl chloride-vinyl acetate copolymer having an average degree of polymerization of 150 to 500, or a weight average molecular weight of 200.
It is preferably a homopolymer or copolymer of a methacrylate monomer of 0 to 60,000, and has abrasion resistance, light resistance, and tamper resistance when it becomes a protective layer after the thermal transfer layer is transferred to the transfer target. It has excellent durability such as properties.

A release layer that does not separate from the base material can be formed between the base material and the heat transfer layer of the heat transfer film, and the transferability of the heat transfer layer can be improved. A release layer that can be peeled from the base material can be formed between the base material and the heat transfer layer of the heat transfer film, and the heat transfer layer together with the release layer can be easily transferred to the transfer target. A release layer that can be peeled from the release layer can be formed between the release layer and the thermal transfer layer of the thermal transfer film, and the thermal transfer layer and the release layer can be easily transferred to the transfer target. The difference in thickness between the convex portion and the other portion of the thermal transfer layer is 0.2 to 5.0 μm.
It is preferable that the thickness is m, whereby the convex portion of the thermal transfer layer transferred to the transfer target can be easily read by reflection of light according to the angle of the line of sight with respect to the transfer surface.

The method for producing a thermal transfer film of the present invention comprises the steps of laminating a thermal transfer film A and a thermal transfer film B each having a thermal transfer layer formed on one side of a substrate at a position farthest from the substrate so that the thermal transfer layers face each other. By partially heating, the thermal transfer layer of the thermal transfer film A is partially transferred to the thermal transfer layer of the thermal transfer film B to form a thermal transfer layer partially having convex portions.

[0011]

The heat transfer film of the present invention has a structure in which a heat transfer layer partially having a convex portion is formed on one side of a base material at a position farthest from the base material. A thermal transfer film A and a thermal transfer film B each having a thermal transfer layer formed at a position farthest from the base material on one side are overlapped so that the thermal transfer layers face each other, and partially heated, thereby thermally transferring the thermal transfer film A. A method is employed in which the layer is partially transferred to the thermal transfer layer of the thermal transfer film B to form a thermal transfer layer partially having a convex portion to produce the thermal transfer layer. The thermal transfer layer having a convex portion partially formed on one side of the above-mentioned substrate is formed on the farthest position from the substrate, and the thermal transfer layer is transferred to the transfer target. For example, an image is previously formed on the transfer target to which the thermal transfer layer is transferred by a thermal transfer recording method or the like, and the thermal transfer layer is transferred onto the image to protect the image and adjust the line of sight to the image recording surface. Correspondingly, the convex portion of the thermal transfer layer transferred to the transferred material can be read by reflection of light. Further, a thermal transfer layer having a convex portion partially on one side of the above-mentioned substrate, a thermal transfer film formed at a position farthest from the substrate, and a thermoplastic resin and a colorant on at least one side of the substrate. The thermal transfer recording medium having the thermal transfer ink layer formed thereon is overlaid so that the thermal transfer layer of the thermal transfer film and the thermal transfer ink layer of the thermal transfer recording medium face each other, and the imagewise heating is performed to form the thermal transfer ink layer or the thermal transfer ink layer of the thermal transfer recording medium. The color image contained in the ink layer is transferred imagewise to the thermal transfer layer of the thermal transfer film to form a reverse image on the thermal transfer film, and then the thermal transfer layer of the imaged thermal transfer film and the image forming surface of the transferred material. And so as to face each other, and by heating from the side opposite to the thermal transfer layer of the thermal transfer film, transfer the entire image-formed thermal transfer layer to the transfer target. Thus, an image is formed on the transfer member. In this case, in the image-transferred material, the image is protected by the thermal transfer layer, and the convex portion of the thermal transfer layer transferred to the material is readable according to the angle of the line of sight to the image recording surface. . With these, the resulting thermal transfer print (transferred material to which the image and the thermal transfer layer are transferred) has excellent durability such as abrasion resistance, light resistance, and tamper resistance, and partially on one side of the substrate. Since the thermal transfer film having the convex portion is provided on the farthest position from the base material, the protective layer and the convex portion can be formed on the transferred material in a single transfer, so that damage caused by the transfer to the transferred material It is possible to suppress deterioration of the quality of printed matter and increase of manufacturing cost.

[0012]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention will be described in more detail below with reference to preferred embodiments. FIG. 1 is a cross-sectional view showing one embodiment of a thermal transfer film 1 of the present invention, in which a thermal transfer layer a (31) and a thermal transfer layer b (3) are formed on a substrate 2.
2) are laminated, the thermal transfer layer b (32) has the shape of a convex portion, and is at the farthest position from the base material 2. In the case of the thermal transfer film of FIG. 1, the transfer target is placed so as to be in contact with the thermal transfer layer 3 of the thermal transfer film 1, and the thermal transfer layer a is applied to the transfer target by heating with a thermal head or a laser from the back side of the substrate 2. (31), the thermal transfer layer b (32) is transferred. FIG. 2 is a cross-sectional view showing another embodiment of the thermal transfer film 1 of the present invention, in which a release layer 4, a thermal transfer layer a (31) and a thermal transfer layer b (32) are laminated in this order on a base material 2. The thermal transfer layer b (32) has the shape of a convex portion, and is at the farthest position from the base material 2. Then, the back surface layer 6 is provided on the other surface of the base material 2. In the case of the thermal transfer film of FIG. 2, the transfer target is placed so as to be in contact with the thermal transfer layer 3 of the thermal transfer film 1, and the thermal transfer layer a (3
1), the thermal transfer layer b (32) is transferred, and the release layer 4 remains on the base material 2 side.

FIG. 3 is a sectional view showing another embodiment of the thermal transfer film 1 of the present invention.
The thermal transfer layer a (31) and the thermal transfer layer b (32) are laminated in this order, and the thermal transfer layer b (32) has a convex shape and is at the farthest position from the base material 2. In the case of the thermal transfer film shown in FIG. 3, the transfer target is placed so as to be in contact with the thermal transfer layer 3 of the thermal transfer film 1, and the release layer 5 is applied to the transfer target by heating from the back side of the base material 2 with a thermal head or a laser. The thermal transfer layer a (31) and the thermal transfer layer b (32) are transferred. FIG. 4 is a cross-sectional view showing another embodiment of the thermal transfer film 1 of the present invention, in which the release layer 4 is formed on the base material 2,
The peeling layer 5, the thermal transfer layer a (31), and the thermal transfer layer b (32) are laminated in this order, and the thermal transfer layer b (32) has a convex shape and is at the farthest position from the base material 2. In the case of the thermal transfer film shown in FIG. 4, the transfer target is placed so as to be in contact with the thermal transfer layer 3 of the thermal transfer film 1, and the release layer 5 is applied to the transfer target by heating from the back side of the substrate 2 with a thermal head or a laser. , Thermal transfer layer a (31), thermal transfer layer b (32)
Is transferred, and the release layer 4 remains on the base material 2 side.

The layers constituting the thermal transfer film of the present invention will be described in detail below. (Substrate) As the substrate 2 used in the thermal transfer film of the present invention, the same substrate as that used in the conventional thermal transfer film can be used as it is, and the surface of the substrate can be subjected to an easy adhesion treatment. It is possible to use the existing ones and others, and there is no particular limitation. Specific examples of preferable substrates include, for example, polyester films including polyethylene terephthalate, polycarbonate, polyamide, polyimide, cellulose acetate, polyvinylidene chloride, polyvinyl chloride, polystyrene, fluororesin, polypropylene, polyethylene, plastic films such as ionomers. , And papers such as glassine paper, condenser paper, and paraffin paper, cellophane, and the like, and also a composite film in which two or more kinds of these are laminated. The thickness of these base materials 2 is appropriately changed depending on the material so that the strength and heat resistance thereof are appropriate, but normally, about 2 to 100 μm is preferable.

(Thermal Transfer Layer) The thermal transfer layer 3 provided on the substrate in the thermal transfer film of the present invention is provided in the shape of a convex at the position farthest from the substrate, but the thermal transfer layer 3 comprises at least two layers. It is configured. The two layers include a thermal transfer layer b having a convex shape and a thermal transfer layer b having a convex shape.
There is a thermal transfer layer a located underneath, and the thermal transfer layer a is transferred onto an image (a thermal transfer image or the like) of a transfer target and functions as a protective layer for the image, and the abrasion resistance and the light resistance of the image. ,
Contributes to durability such as tamper resistance. The thermal transfer layer b is transferred to the transfer target, and the convex portion of the thermal transfer layer can be read by reflection of light according to the angle of the line of sight with respect to the transferred surface, has tamper resistance, and has a three-dimensional appearance. Is obtained. The thermal transfer layer b forms convex portions formed by characters and image patterns.

The thermal transfer layer is composed of at least two layers, a thermal transfer layer a and a thermal transfer layer b, and the same material is used for each layer. For the thermal transfer layer, a resin excellent in abrasion resistance, transparency, hardness and the like can be used appropriately. Specifically, polyester resin, vinyl chloride-vinyl acetate copolymer, polystyrene resin, acrylic resin,
Examples include polyurethane resins, acrylic urethane resins, polycarbonate resins, silicone-modified resins of these resins, and mixtures of these resins. Further, a resin obtained by crosslinking and curing an acrylic monomer or the like by irradiation with ionizing radiation can also be used. Specific examples of the acrylic monomer include, for example, ethylene glycol di (meth) acrylate, hexanediol di (meth) acrylate, trimethylolpropane tri (meth) acrylate, trimethylolpropane di (meth) acrylate, pentaerythritol tetra (meth). Acrylate, dipentaerythritol hexa (meth) acrylate, ethylene glycol diglycidyl ether di (meth) acrylate,
Propylene glycol diglycidyl ether di (meth)
Examples thereof include acrylate and sorbitol tetraglycidyl ether tetra (meth) acrylate. Further, the substance cured by ionizing radiation is not limited to the above-mentioned monomer, and may be used as an oligomer. Furthermore, an acrylic reactive polymer such as a polyester acrylate type, an epoxy acrylate type, a urethane acrylate type, or a polyether acrylate type, which is a polymer of the above substance or a derivative thereof, can be used. Further, it may be used by mixing with other acrylic resin. Further, in consideration of the film breaking property at the time of transfer of these resins, highly transparent fine particles such as silica, alumina, calcium carbonate, and plastic pigment, wax, etc. may be contained to such an extent that the transparency is not impaired. In order to improve the abrasion resistance and gloss of the image,
A lubricant or the like may be included.

The thermal transfer layer has a glass transition point of 5 as a main component.
It is preferable to contain a thermoplastic resin having a temperature of 0 to 120 ° C., and it becomes excellent in durability such as abrasion resistance and light resistance when it becomes a protective layer after the thermal transfer layer is transferred to a transfer target. . As the thermoplastic resin, a number average molecular weight of 2000 to
30,000 polyester resin, average degree of polymerization 150 to 5
00 vinyl chloride-vinyl acetate copolymer, or a homopolymer or copolymer of a methacrylate monomer having a weight average molecular weight of 20,000 to 60,000 is preferably used, whereby transferability and fixing property to a transfer target are improved. It will be good. Examples of the acid component of the polyester resin include aromatic compounds such as terephthalic acid, isophthalic acid, orthophthalic acid, and 2,6-naphthalenedicarboxylic acid, and examples of the aliphatic or alicyclic dicarboxylic acid include: Examples thereof include succinic acid, adipic acid, azelaic acid, sebacic acid, dodecanedioic acid, dimer acid, tetrahydrophthalic acid, hexahydrophthalic acid, hexahydroisophthalic acid and hexahydroterephthalic acid. Further, a tricarboxylic or higher functional polycarboxylic acid such as trimellitic acid or pyromellitic acid can be used. As the thermal transfer layer in the thermal transfer film of the present invention, the polyester resin containing an acid component, particularly terephthalic acid, isophthalic acid, and trimellitic acid as constituent monomers, has abrasion resistance and light resistance when it becomes a protective layer. It is preferable because it has excellent durability such as properties.

As the alcohol component which is another raw material of the polyester resin, ethylene glycol, 1, 2
-Propylene glycol, 1,3-propanediol,
1,4-butanediol, neopentyl glycol,
1,5-Pentanediol, 1,6-hexanediol, 1,4-cyclohexanedimimethanol, tricyclodecane glycol and the like are listed, and durability such as abrasion resistance and light resistance when forming a protective layer and From the standpoint of transferability, fixability, etc., those using at least two or more selected from ethylene glycol, neopentyl glycol and tricyclodecane glycol as constituent monomers have a glass transition point of 50 to 120 ° C. and a number average molecular weight of 2000
It is easy to adjust to a range of up to 30,000, which is preferable.

As a thermoplastic resin which is preferably used in the thermal transfer layer, a vinyl chloride-vinyl acetate copolymer can be mentioned. This vinyl chloride-vinyl acetate copolymer has a glass transition point of 50 to 120 ° C. and an average degree of polymerization of 150 to 50.
It is preferable to use one having a range of 0. Further, when obtaining such a vinyl chloride-vinyl acetate copolymer, it is preferable to add 5 to 40% by weight of a vinyl acetate monomer. If the blending amount of vinyl acetate is too large, a blocking phenomenon is likely to occur, while if the blending amount of vinyl acetate is too small, the solubility in a solvent used for coating on a substrate becomes low and coating becomes difficult.

Further, the thermoplastic resin constituting the thermal transfer layer is preferably a homopolymer or copolymer of a methacrylate monomer. Examples of the above-mentioned methacrylate-based monomer include methyl methacrylate, ethyl methacrylate, n-propyl methacrylate, i
-Propylmethacrylate, n-butylmethacrylate, i-butylmethacrylate, sec-butylmethacrylate, cyclohexylmethacrylate, benzylmethacrylate, 2-ethylhexylmethacrylate,
2-hydroxyethyl methacrylate, 2-hydroxypropyl methacrylate and the like can be mentioned.

The thermal transfer layer is prepared by dissolving the above resin for the thermal transfer layer with necessary additives added thereto in an appropriate organic solvent or dispersing it in an organic solvent or water, for example, a gravure coat, It is formed by coating and drying the base material by a forming means such as gravure reverse coat or roll coat. The thermal transfer layer can be formed to have an arbitrary thickness, but the thickness after drying is preferably 0.1 to 50.
g / m ² , and more preferably 0.2 to 10 g / m ² .

In the thermal transfer film of the present invention, a thermal transfer layer is provided on a substrate so that it can be peeled off. By providing a thermal transfer layer on a substrate via a release layer, the thermal transfer layer is peeled off from the substrate by heating. It can be made easier. This release layer does not separate from the substrate during thermal transfer and remains on the substrate side. (Release Layer) In the thermal transfer film, the releasability at the time of thermal transfer may not be sufficient depending on the combination of the material of the substrate and the thermal transfer layer. In such a case, the release layer 4 can be provided in advance on the base material. The release layer is made of one or more of waxes, silicone wax, silicone resin, fluororesin, acrylic resin, polyvinyl alcohol, urethane resin, cellulose-based resin such as cellulose acetate, polyvinyl acetal resin, polyvinyl butyral resin and the like. One or more kinds may be selected and used, and when two or more kinds are mixed, a water-soluble resin may be appropriately used. Then, a coating solution containing these resins as a main component can be formed by applying and drying by a conventionally known method such as gravure coating or gravure reverse coating, and the thickness of the coating film can be 0.
About 1 to ² g / m ² is sufficient. It should be noted that when selecting the material used for the release layer, it should be noted that the material has proper release properties with respect to the thermal transfer layer. It is important to increase the adhesive strength with the base material rather than the force. If the adhesive strength with the base material is insufficient, it may cause abnormal transfer such as transfer of the thermal transfer layer with the release layer. . Further, when a matte surface appearance is desired in the printed matter after transfer, by incorporating various particles in the release layer, or by using a base material having the release layer side surface mat-treated Alternatively, the surface of the printed matter on which the thermal transfer layer is transferred can be matted.

In the heat transfer film of the present invention, a heat transfer layer is provided on a base material so that it can be peeled off. However, a heat transfer layer is provided on the base material via a release layer, and the heat transfer layer is peeled from the base material by heating. Can be made easier. This peeling layer can be peeled off from the substrate during thermal transfer. (Peeling layer) The peeling layer 5 includes waxes, silicone wax, silicone resin, fluororesin, acrylic resin, polyvinyl alcohol resin, cellulose derivative resin, polyvinyl acetal resin, polyvinyl butyral resin, vinyl chloride-vinyl acetate copolymer, chlorine. A coating solution containing a modified polyolefin, etc., and a copolymer of these resins, etc. is applied by a conventionally known gravure printing method, a screen printing method, a forming means such as a reverse roll coating method using a gravure plate, etc. It can be dried, and formed. The thickness of the release layer is 0.01 to 5 g / m ^{2 in} a dry state.
It is a degree.

Further, in the thermal transfer film, an adhesive layer may be provided on the thermal transfer layer provided on the substrate to improve the fixability of the thermal transfer film to the transferred material at the time of thermal transfer. For this adhesive layer, it is preferable to select a material that exhibits adhesiveness by heating, and examples thereof include thermoplastic synthetic resin, natural resin,
It can be formed using rubber, wax or the like by the same forming means as the above-mentioned release layer. The thickness of the adhesive layer is
It is about 0.01 to 5 g / m ² .

(Back Layer) Further, with respect to the base material of the thermal transfer film, the surface of the base material opposite to the surface on which the thermal transfer layer is provided is prevented from sticking to a thermal head or the like and has slipperiness. It is possible to provide a back layer 6 for the sake of improvement. Examples of the resin used for the back surface layer include ethyl cellulose, hydroxycellulose, hydroxypropyl cellulose, methyl cellulose, cellulose acetate, cellulose acetate butyrate, cellulose resins such as nitrocellulose, polyvinyl alcohol, polyvinyl acetate, polyvinyl butyral, polyvinyl acetal, and the like. Vinyl-based resin such as polyvinylpyrrolidone, acrylic-based resin such as polymethylmethacrylate, polyethylacrylate, polyacrylamide, acrylonitrile-styrene copolymer, polyamide resin, polyvinyltoluene resin, coumarone-indene resin, polyester-based resin, polyurethane A single substance or a mixture of natural or synthetic resins such as resin, silicone-modified or fluorine-modified urethane is used. Among the above resins to further improve the heat resistance of the back layer, a resin having a hydroxyl group reactive group is used, and a polyisocyanate or the like is used in combination as a crosslinking agent to form a crosslinked resin layer. preferable.

Further, in order to provide slidability with the thermal head, a solid or liquid release agent or lubricant may be added to the back surface layer so as to have heat resistant slipping property. Examples of the release agent or lubricant include various waxes such as polyethylene wax and paraffin wax, higher aliphatic alcohols,
Organopolysiloxane, anionic surfactant, cationic surfactant, amphoteric surfactant, nonionic surfactant, fluorine surfactant, organic carboxylic acid and its derivatives, fluorine resin, silicone resin, talc, Fine particles of an inorganic compound such as silica can be used.
The amount of lubricant contained in the back layer is 5 to 50% by weight, preferably about 10 to 30% by weight. The means for forming the back layer is prepared by dissolving or dispersing a releasing agent, a lubricant or the like in the resin in a suitable solvent as described above to prepare a coating solution and gravure the coating solution. It is coated and dried by a conventional coating means such as a coater, a roll coater, and a wire bar. The coating amount of the back surface layer is about 0.1 to 10 g / m ^{2 in} a dry state.

(Method for Manufacturing Thermal Transfer Film) A method for manufacturing the thermal transfer film described above will be described below. FIG. 5 is a schematic view of one embodiment for explaining the method for producing the thermal transfer film of the present invention, in which the release layer 4 and the thermal transfer layer b (32) are provided in this order on one side of the substrate 2. The thermal transfer film A (11), in other words, the thermal transfer film A (11) in which the thermal transfer layer b (32) was formed at the farthest position from the substrate 2, and the thermal transfer layer a (31) were provided on one side of the substrate 2. The thermal transfer film B (12), that is, the thermal transfer film B (12) in which the thermal transfer layer a (31) is formed at the farthest position from the substrate 2, is superposed so that the thermal transfer layers face each other, and the thermal head By partially heating from the back side of the thermal transfer film A (11) by 8, and the thermal transfer film A (11) and the thermal transfer film B (12) are superposed,
The two thermal transfer films are pressed by the thermal head 8 and the platen roll 9, and the thermal transfer layer b (32) of the thermal transfer film A (11) is partially transferred to the thermal transfer layer a (31) of the thermal transfer film B (12). By doing so, the thermal transfer film 12 in which the thermal transfer layer b (32) partially having the convex portion 7 is formed can be prepared. The thermal transfer film 12 has a thermal transfer layer 32 having a convex portion 7 partially on one side of the substrate 2.
Is formed at a position farthest from the base material 2.

As described above, in order to form the thermal transfer layer partially having convex portions on the substrate, the thermal transfer film prepared separately is partially heated by using a heat source such as a thermal head. The convex portion can be formed by thermal transfer. However, it is not limited to forming the convex portion by the thermal transfer means,
In the present invention, for example, an inkjet ink is used to form a convex portion by an inkjet recording method in which the ink is partially discharged from a nozzle, or an electrophotographic method is used to expose an electrostatic latent image on a photoreceptor by exposure. It is also possible to form the latent image, develop the latent image with a transparent toner, and then transfer the toner image as a convex portion onto the thermal transfer film to form the latent image. By setting the difference in thickness between the convex portion of the thermal transfer layer formed as described above and the other portion, that is, the portion adjacent to the convex portion within the range of 0.2 to 5.0 μm, the transfer target is formed. Since the convex portion of the thermal transfer layer transferred to (1) becomes easy to read by the reflection of light according to the angle of the line of sight with respect to the transfer surface, it is preferable that the thickness difference be within the above range.
For example, when the convex portion is formed by the thermal transfer means,
A thermal transfer layer for forming the convex portion is prepared and prepared in advance in the form of a thermal transfer film with the above thickness, and the thermal transfer layer is collectively thermally transferred in the thickness direction (without being left on the substrate side). Is desirable.

[0029]

EXAMPLES The present invention will be described more specifically with reference to Examples and Comparative Examples below. In addition, "parts" and "%" are based on weight. (Production of Thermal Transfer Film 1 to Thermal Transfer Film 30) Table 5
The thermal transfer film 1 to the thermal transfer film 30 are produced under the conditions of the respective layers shown in FIG. That is, a back layer having the composition shown in Table 4 was coated on the base material shown in Table 5 so that the solid content was 0.2 g / m ^2, and the other surface of the base material was coated under the conditions shown in Table 5. , A release layer, a release layer, and a thermal transfer layer are sequentially formed.
The composition of the release layer is as shown in Table 5, and the details of the resin used are shown in Table 2. The composition of the release layer is shown in Table 5, and the details of the resin used are shown in Table 3. The composition of the thermal transfer layer is as shown in Table 5, and the details of the resin used are shown in Table 1.

[0030]

[Table 1]

[0031]

[Table 2]

[0032]

[Table 3]

[0033]

[Table 4]

[0034]

[Table 5]

(Production of Thermal Transfer Ink Sheet 1 to Thermal Transfer Ink Sheet 5) Thermal transfer ink sheet 1 to thermal transfer ink sheet 5 for forming a colored image were produced under the conditions of each layer shown in Table 6.

[Table 6]

(Transfer Material) When evaluating the thermal transfer film, a white soft vinyl chloride sheet having a thickness of 200 μm or a black polycarbonate sheet having a thickness of 200 μm was used as a material to be transferred.

(Examples 1 to 25), (Comparative Examples 1 to 1)
Comparative Example 4) In a combination as shown in Table 7, the thermal transfer film A and the thermal transfer film B were superposed so that their thermal transfer layers face each other, and imagewise heating was performed from the back side of the thermal transfer film A with a thermal head, The thermal transfer layer of the thermal transfer film A was transferred imagewise onto the thermal transfer layer of the thermal transfer film B, and the thermal transfer layer having convex portions on the base material, which was used in Examples and Comparative Examples, was formed at the position farthest from the base material. Prepare a thermal transfer film. In each thermal transfer film provided with the thermal transfer layer having the obtained convex portion, the difference in thickness between the convex portion of the thermal transfer layer and the other portion was measured, and shown in Table 7 as the thickness of the convex portion. When forming the thermal transfer layer having the above-mentioned convex portions, the thermal head was heated under the following printing conditions. The printer is an evaluation printer and the line speed is 2.8 ms.
ec / line, pulse duty 80%, resolution of the thermal head is 300 DPI, thermal head resistance value is 1600Ω, and applied voltage is 17.5V.

[0038]

[Table 7]

(Colored Image and Non-Colored Image Forming Method-Direct Transfer-) The transfer target and the thermal transfer ink sheet are superposed so that one surface of the transfer target and the colored layer of the thermal transfer ink sheet face each other, and thermal transfer is performed. A colored image is directly formed on the transfer target by imagewise heating from the back side of the ink sheet with a thermal head and transferring the colorant alone or the colorant and binder to the transfer target. (Thermal transfer ink sheet 1,
In the case of 2, the colorant and the binder are transferred to the transfer target, and in the case of the thermal transfer ink sheets 3, 4 and 5, only the colorant is transferred to the transfer target. ) After that, the image forming surface of the transferred material on which the colored image is formed, and the above-mentioned method,
The thermal transfer film provided with a thermal transfer layer having a convex portion is laminated so as to face the thermal transfer layer, and the entire surface is heated from the back side of the thermal transfer film by a heat roll covered with rubber heated to 180 ° C. By transferring the entire surface of the thermal transfer layer, a non-colored image is formed on the transfer target. still,
The printing conditions for the colored image are the same as the printing conditions for producing the thermal transfer film provided with the thermal transfer layer having the convex portions.

(Colored Image and Non-Colored Image Forming Method-Retransfer-) A thermal transfer film and a thermal transfer ink sheet provided with a thermal transfer layer having a convex portion prepared by the above method are used to form a thermal transfer layer of a thermal transfer film and a thermal transfer ink sheet. It is superposed so that the colored layers face each other, and imagewise is heated from the back side of the thermal transfer ink sheet with a thermal head, and only the colorant or the colorant and binder is imagewise transferred onto the thermal transfer layer of the thermal transfer film. This forms a colored image on the thermal transfer layer of the thermal transfer film. Then, the transferred material and the colored image are superposed so that the colored image and the thermal transfer layer of the thermal transfer film formed on the thermal transfer layer face each other, and a heat roll covered with rubber heated to 180 ° C. from the back side of the thermal transfer film. The entire surface of the thermal transfer layer of the thermal transfer film is transferred by heating, and a colored image and a non-colored image are formed on the transfer target. The printing conditions for the colored image are the same as the printing conditions for producing the thermal transfer film provided with the thermal transfer layer having the convex portions.

As Examples 1 to 25 and Comparative Examples 1 to 4, a thermal transfer film provided with a thermal transfer layer having a convex portion prepared in each example, a thermal transfer ink sheet for forming a colored image, and an object to be transferred were used. A colored image and a non-colored image were formed on the transferred material by the combination used under the conditions shown in Table 7 and by the method shown in Table 7. The following evaluations were carried out using a transferred material on which a colored image and a non-colored image were formed and a thermal transfer film provided with a thermal transfer layer having a convex portion.

(Visibility of non-colored convex image) As a thermal transfer film provided with a thermal transfer layer having a convex portion, the thermal transfer film A
The thermal transfer layer of 7 points was transferred onto the thermal transfer layer of the thermal transfer film B in a character shape of "ABC" to form a non-colored image and a colored image on the transfer target by the method described above. The readability of "ABC" was evaluated. (Transferability) In the transfer target in which the non-colored image and the colored image are formed on the transfer target by the above-described method, transfer failure (there is a part where the thermal transfer layer of the thermal transfer film is not transferred) The presence or absence of the thermal transfer layer transferred to the transfer member protruding from the end surface of the transfer target) was visually observed to evaluate transferability.

(Abrasion resistance) With respect to the non-colored image and the transferred material on which the colored image is formed, the abrasion resistance test of 200 rotations is carried out by using a wear wheel CS-10F with a TABER tester and a load of 500 gf. Then, the presence or absence of a defect in the colored image was evaluated. (Heat resistance) The thermal transfer layer of the thermal transfer film and the back layer of the thermal transfer film were superposed and a storage test was carried out at 50 ° C. for 2 days to evaluate the presence or absence of blocking.

The evaluation results of each Example and Comparative Example are shown in Table 7.

[0045]

INDUSTRIAL APPLICABILITY As described above, the thermal transfer film of the present invention comprises a thermal transfer layer having a partial convex portion on one side of a substrate.
The thermal transfer film is formed at a position farthest from the base material, and in order to manufacture the thermal transfer film, the thermal transfer film A and the thermal transfer film B, each having a thermal transfer layer formed on one side of the base material at the farthest position from the base material, are separated from each other. The thermal transfer layer of the thermal transfer film A is partially transferred to the thermal transfer layer of the thermal transfer film B by overlapping so that the thermal transfer layers face each other and partially heated to form a thermal transfer layer partially having a convex portion. Then, the manufacturing method is adopted. The thermal transfer layer having a convex portion partially on one side of the above-mentioned substrate is formed on the farthest position from the substrate, and the thermal transfer layer is transferred to the transfer target. There are two types of image formation. One is that an image has been previously formed on the transfer-receiving member that transfers the thermal transfer layer by a thermal transfer recording method,
By transferring the thermal transfer layer onto the image, the image can be protected and the convex portion of the thermal transfer layer transferred to the transfer target according to the angle of the line of sight with respect to the image recording surface can be read by light reflection.

The other is a thermal transfer containing a thermoplastic resin and a colorant on at least one side of a base material in the thermal transfer layer of the thermal transfer film of the present invention, without directly forming an image on the transferred material. The thermal transfer ink layer or the colorant contained in the thermal transfer ink layer is transferred imagewise from the thermal transfer recording medium having the ink layer formed thereon to the thermal transfer layer of the thermal transfer film to form an image reverse image on the thermal transfer film, and then an image is formed. The thermal transfer layer of the thermal transfer film and the image forming surface of the transferred material are superposed so as to face each other, and by transferring the imaged thermal transfer layer to the transferred material, an image can be formed on the transferred material. . In this case, in the image-transferred material, the image is protected by the thermal transfer layer, and the convex portion of the thermal transfer layer transferred to the material is readable according to the angle of the line of sight to the image recording surface. . With these,
The resulting thermal transfer print (transferred material on which the image and thermal transfer layer are transferred) has excellent durability such as abrasion resistance, light resistance, and tamper resistance, and a convex portion is partially formed on one side of the substrate. The thermal transfer layer having the protective layer and the convex portions can be formed on the transferred material by one transfer using the thermal transfer film provided at the farthest position from the base material, so that the transfer object is less damaged by the transfer, It is possible to suppress deterioration of print quality and increase of manufacturing cost.

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing one embodiment of a thermal transfer film of the present invention.

FIG. 2 is a cross-sectional view showing another embodiment of the thermal transfer film of the present invention.

FIG. 3 is a cross-sectional view showing another embodiment of the thermal transfer film of the present invention.

FIG. 4 is a cross-sectional view showing another embodiment of the thermal transfer film of the present invention.

FIG. 5 is a schematic view of one embodiment illustrating a method for producing the thermal transfer film of the present invention.

[Explanation of symbols]

1 Thermal transfer film 2 base materials 3 Thermal transfer layer 4 Release layer 5 Release layer 6 back layer 7 convex 8 thermal head 9 Platen roll 11 Thermal transfer film A 12 Thermal transfer film B 31 thermal transfer layer a 32 thermal transfer layer b

   ─────────────────────────────────────────────────── ─── Continued front page    F-term (reference) 2H111 AA05 AA07 AA09 AA10 AA26                       AA27 AA33 AA52 AB07 CA03                       CA13 CA25 CA31 CA41                 3B005 EA01 EA06 EB01 EB03 EC02                       EC05 EC28 EC30 FB03 FB06                       FB13 FB57 FB58 FC02X                       FC02Y FC02Z FC04Y FC04Z                       FC08Y FC08Z FD01Y FD01Z                       FD03Y FD03Z FD05Y FD05Z                       GA04 GB01 GC06 GC10

Claims (8)

[Claims] 1. A thermal transfer film, characterized in that a thermal transfer layer having a convex portion partially on one side of the substrate is formed at a position farthest from the substrate. 2. A thermal transfer film, wherein the thermal transfer layer according to claim 1 contains a thermoplastic resin having a glass transition point of 50 to 120 ° C. as a main component. 3. The thermoplastic resin according to claim 2, wherein the thermoplastic resin has a number average molecular weight of 2000 to 30000, a vinyl chloride-vinyl acetate copolymer having an average degree of polymerization of 150 to 500, or a weight average molecular weight of 20,000 to 60,000. A thermal transfer film comprising a homopolymer or a copolymer of a methacrylate monomer. 4. A thermal transfer film comprising a release layer which is not peeled off from the base material between the base material and the thermal transfer layer of the thermal transfer film according to claim 1. 5. A thermal transfer film comprising a thermal transfer film according to any one of claims 1 to 3 and a thermal transfer layer formed between the substrate and the thermal transfer layer. 6. A thermal transfer film comprising a thermal transfer film according to claim 4 and a thermal transfer layer having a release layer formed between the thermal transfer layer and the release layer. 7. A thermal transfer film, wherein the difference in thickness between the convex portion and the other portion of the thermal transfer layer according to claim 1 is 0.2 to 5.0 μm. 8. A thermal transfer film A and a thermal transfer film B, each having a thermal transfer layer formed on one side of a substrate at a position farthest from the substrate, are superposed so that the thermal transfer layers face each other, and partially heated. The thermal transfer layer of Claims 1 to 7 is formed by partially transferring the thermal transfer layer of the thermal transfer film A to the thermal transfer layer of the thermal transfer film B to form a thermal transfer layer partially having a convex portion. Production method.