JPH0852947A - Thermal transfer sheet - Google Patents

Abstract

PURPOSE:To provide a thermal transfer sheet excellent not only in antistatic properties but also in the close adhesiveness of a thermal transfer colorant layer and a heat-resistant slip layer to a base material film. CONSTITUTION:A thermal transfer sheet is constituted by forming a thermal transfer colorant layer 2 and an antistatic layer on a base material film 1 and the antistatic layer 3 is composed of an antistatic resin consisting of an acrylic resin and an epoxy resin.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a thermal transfer sheet, and more particularly to a novel thermal transfer sheet having an excellent antistatic layer made of a specific material.

[0002]

2. Description of the Related Art Conventionally, as a thermal transfer sheet, a sublimation type thermal transfer sheet having a dye layer composed of a sublimable dye and a binder provided on one surface of a polyester film or the like, and a pigment and a wax instead of the dye layer are used. A heat-melting type thermal transfer sheet provided with an ink layer is known. These thermal transfer sheets are heated imagewise from the back side by a thermal head to transfer the dye of the dye layer or the ink layer to the transfer material to form an image.

[0003]

DISCLOSURE OF THE INVENTION Problems to be Solved by the Invention The above-mentioned thermal transfer sheet is made of various materials constituting the thermal transfer sheet, in particular, the surface resistivity of the base film is as high as 10 ¹⁴ or more. Are easily charged due to mutual friction at the time of forming, small winding, storing a cassette, packing in a box, and the like. Further, during use, there is a problem in that charging is likely to occur during contact with the ribbon feed roll or the transfer material, contact with the thermal head, or peeling from the transfer material after printing. When the thermal transfer sheet is charged, dust or the like is likely to adhere to the surface of the thermal transfer sheet, and as a result, the dust or the like adheres to the thermal head, which lowers the resolution of the formed image. Similarly, the material to be transferred such as paper is also charged, and the thermal transfer sheet and the material to be transferred are stuck to each other, and when the thermal transfer sheet and the material to be transferred are conveyed, folds and wrinkles are generated on the thermal transfer sheet, which causes a problem of defective printing. . Further, in extreme cases, sparks may be caused when the thermal transfer roll or the material to be transferred is replaced or inserted, and a human body may be impacted.

As a method of solving such a problem, there is a method of imparting an antistatic function to the printer itself, but these methods do not sufficiently prevent the thermal transfer sheet from being antistatic. As another method, it is known to form an antistatic layer on the thermal transfer sheet itself. When the antistatic layer is formed of a surfactant or the like, the thermal transfer sheet may become sticky, or when the thermal transfer sheet is wound into a roll, the antistatic agent may migrate to the coloring material layer, or vice versa. Is transferred to the back surface of the thermal transfer sheet. Further, in addition to these problems, there is a problem that the antistatic effect of the antistatic layer decreases with time. Such a problem does not occur if the antistatic layer is provided between the substrate film and the heat transferable coloring material layer or between the substrate film and the heat resistant slipping layer. The adhesiveness of the color material layer and the heat resistant slipping layer to the base film is extremely reduced, which is not practical. Therefore,
An object of the present invention is to provide a thermal transfer sheet which is excellent in antistatic properties and also in the adhesiveness of the thermal transferable color material layer and the heat resistant slipping layer to the substrate film.

[0005]

The above object can be achieved by the present invention described below. That is, the present invention is characterized in that a heat transferable color material layer and an antistatic layer are formed on a substrate film, and the antistatic layer is made of an antistatic resin composed of an acrylic resin and an epoxy resin. It is a thermal transfer sheet.

[0006]

By forming the antistatic layer of the thermal transfer sheet from an antistatic resin composed of an acrylic resin and an epoxy resin, the antistatic property is excellent and the thermal transferable color material layer and the heat-resistant slipping layer are applied to the base film. A thermal transfer sheet having excellent adhesion can be provided.

[0007]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention will be described in more detail with reference to the preferred embodiments. The thermal transfer sheet of the present invention,
As shown in some examples in FIG. 1, a base film 1
A thermal transferable color material layer 2 and an antistatic layer 3 are formed on the top of the layer, and the antistatic layer 3 is made of an antistatic resin composed of an acrylic resin and an epoxy resin.
As shown in FIG. 1 a, a primer layer 4, an antistatic layer 3 and a heat transferable color material layer 2 are laminated in this order on one side of a base film 1, and the primer layer 4 is formed on the other side of the base film 1. And an example in which the heat resistant slipping layer 5 is laminated, as shown in FIG. 1b, the primer layer 4 and the heat transferable coloring material layer 2 are laminated on one surface of the substrate film 1 in this order to form the substrate film 1.
An example in which a primer layer 4, an antistatic layer 3 and a heat resistant slipping layer 5 are laminated on the other surface of the base film 1 as shown in FIG. 1c.
An example in which the antistatic layer 3 and the heat transferable color material layer 2 are laminated in this order on one surface of the base film 1, and the primer layer 4 and the heat resistant slipping layer 5 are laminated on the other surface of the base film 1, as shown in FIG. 1d. As shown, the primer layer 4 and the heat transferable color material layer 2 are laminated in this order on one surface of the base film 1, and the antistatic layer 3 and the heat resistant slipping layer 5 are formed on the other surface of the base film 1. Examples including laminated layers are included. In these examples, the primer layer is not essential when the base film is a film having good adhesiveness. Further, when the base film has excellent heat resistance and lubricity, the heat resistant slipping layer is not essential.

The substrate film used in the thermal transfer sheet of the present invention may be any one as long as it has conventionally known heat resistance and strength to some extent.
Paper having a thickness of 5 to 50 μm, preferably about 3 to 10 μm, various processed papers, polyester film, polystyrene film, polypropylene film, polysulfone film, aramid film, polycarbonate film,
Polyvinyl alcohol film, cellophane, etc.,
Particularly preferred is a polyester film. These substrate films may be of single-wafer type or continuous film, and are not particularly limited. Among these, polyethylene terephthalate film is particularly preferable, and it is also preferable to form a primer layer or an adhesive layer on one side or both sides of the film, if necessary.

The antistatic layer formed on one surface of the base film is made of an antistatic resin composed of an acrylic resin and an epoxy resin. Such an antistatic resin is commercially available as a two-component type antistatic adhesive consisting of an acrylic resin and an epoxy resin, and is obtained from the market under the name Bondip (registered trademark) by Konishi Bond Co., Ltd., for example. Can be used in the present invention. Since this antistatic resin also has excellent adhesiveness, it significantly improves the adhesion of the heat transferable color material layer to the base material film, and also significantly improves the adhesion of the heat resistant slipping layer to the base material film. There is an action.

Examples of the above-mentioned acrylic resin include, for example, a copolymer of an acrylic monomer having a quaternary ammonium group and an acrylic monomer having a group which reacts with an epoxy group. Examples of the acrylic monomer having a quaternary ammonium salt group include dimethylaminoethyl (meth) acrylate, diethylamino (meth) acrylate, diethanolamino (meth) acrylate, dipropylamino (meth) acrylate,
Examples thereof include (meth) acrylic acid ester monomers having a tertiary amino group such as dipropanolamino (meth) acrylate and dibutylamino (meth) acrylate, and quaternized monomers thereof.

Further, as the acrylic monomer, acrylic acid, methacrylic acid, or a monomer having a reactive group such as a carboxyl group or a hydroxyl group such as acrylic acid, methacrylic acid, or mono (meth) acrylate of glycol such as ethylene glycol, Reaction of glycidyltrimethylammonium chloride, 3-chloro-2-hydroxypropyltrimethylammonium chloride, 3-chloro-2-hydroxypropyltrietanolinammonium chloride, glycidyltrimethylammonium chloride, glycidyldimethylbenzylammonium chloride, glycidyldimethylbutylammonium chloride, etc. A monomer obtained by reacting a soluble quaternary ammonium salt is mentioned.

On the other hand, as the acrylic monomer having a group capable of reacting with an epoxy group, for example, acrylic acid, methacrylic acid, or these monomers and ethylene glycol,
Examples thereof include esterification products with polyhydric alcohols such as propylene glycol, glycerin and pentaerythritol, amidation products with polyvalent amines such as ethylenediamine and propylenediamine, acrylamide and methacrylamide.

Examples of the epoxy resin which crosslinks or cures the copolymer of the above monomers include bisphenol A.
Diglycidyl ether, bisphenol F diglycidyl ether, bisphenol A diglycidyl ether, bisphenol S diglycidyl ether, bisphenol A diβ-methylglycidyl ether, bisphenol hexafluoroacetone diglycidyl ether, tetraphenyl diglycidyl ether, trimethylolpropane triglycidyl ether Common epoxy resins such as ether, resorcinol diglycidyl ether, hydrogenated bisphenol A diglycidyl ether and the like can be mentioned.

The acrylic resin (main agent) and epoxy resin (hardening agent) as described above are all water, methanol, ethanol, isopropyl alcohol, acetone, methyl ethyl ketone, methyl isobutyl ketone, ethyl acetate, toluene, xylene, or the like. Used as a 10 to 50% by weight solution of the mixture, with an equivalence ratio of about 1: 1 when used.
It is mixed at a ratio of and diluted as necessary before use. The antistatic layer in the present invention is obtained by applying a coating solution prepared by mixing the above-mentioned main ingredient and curing agent in an appropriate ratio on a primer layer provided on at least one surface of the base film or the base film by a conventional method. It can be formed by working and drying. This antistatic layer may be provided on the surface of the base film on the side where the heat transferable color material layer is formed, and the heat transferable color material layer may be provided thereon, or the surface on which the heat transferable color material layer is formed. It may be provided on the surface on the opposite side, and a heat resistant slipping layer may be provided on the surface of the antistatic layer. The coating method may be a conventional coating means such as a gravure coater, roll coater, wire bar or the like. The coating amount of the coating liquid is preferably such that the thickness of the antistatic layer formed is in the range of about 0.1 to 5 μm.

In the case of a sublimation type thermal transfer sheet, a layer containing a sublimable dye is formed as the coloring material layer formed on the surface of the substrate film or the antistatic layer, while the color material layer of the heat melting type thermal transfer sheet is formed. In some cases, a wax ink layer colored with a pigment is formed. The case of a sublimation type thermal transfer sheet will be described below as a typical example, but the present invention is not limited to the sublimation type thermal transfer sheet. As the dye used in the dye layer,
Any of the dyes used in conventionally known thermal transfer sheets can be effectively used in the present invention and is not particularly limited. For example, some preferred dyes include red dyes such as MS Red G, Macrolex Red
Violet R, Ceres Red7B, Sam
aronRed HBSL, Resolin Red
F3BS and the like, and yellow dyes such as Holon Brilliant Yellow 6GL, PTY-52 and Macrolex Yellow 6G, and blue dyes such as Kayaset Blue 714 and Waxolin Blue A.
P-FW, Holon Brilliant Blue SR, MS Blue 100 and the like can be mentioned.

Preferred binder resins for carrying the above dyes are exemplified by cellulose resins such as ethyl cellulose, hydroxyethyl cellulose, ethyl hydroxy cellulose, hydroxypropyl cellulose, methyl cellulose, cellulose acetate, and cellulose acetate butyrate, and polyvinyl resins. Alcohol, polyvinyl acetate,
Examples include vinyl resins such as polyvinyl butyral, polyvinyl acetal, and polyvinylpyrrolidone, acrylic resins such as poly (meth) acrylate and poly (meth) acrylamide, polyurethane resins, polyamide resins, polyester resins, and the like. Among them, cellulose-based, vinyl-based, acrylic-based, polyurethane-based, polyester-based resins and the like are preferable from the viewpoints of heat resistance, dye migration, and the like.

The dye layer is prepared by dissolving one of the above-mentioned base film and the above-described dye and binder, if necessary, with additives such as a release agent, dissolved in a suitable organic solvent. Or a dispersion dispersed in an organic solvent or water,
For example, it can be formed by applying and drying by a forming means such as a gravure printing method, a screen printing method, and a reverse roll coating method using a gravure plate. The dye layer thus formed has a thickness of about 0.2 to 5.0 μm, preferably about 0.4 to 2.0 μm, and the sublimable dye in the dye layer contains 5% by weight of the dye layer. Suitably it is present in an amount of ˜90% by weight, preferably 10 to 70% by weight. The dye layer to be formed is formed by selecting one color from the above dyes when the desired image is a mono color image, and when the desired image is a full color image, for example, a suitable cyan, magenta and Yellow (and optionally black) is selected to form yellow, magenta and cyan (and optionally black) dye layers.

In a preferred embodiment of the present invention, a heat resistant slipping layer is formed on the surface of the substrate film or the surface of the antistatic layer opposite to the surface on which the heat transferable color material layer is formed. The heat resistant slipping layer may be a heat resistant slipping layer similar to those known in the prior art. For example, it is formed as a crosslinked resin layer from a hydroxyl group-containing resin such as polyvinyl butyral, polyvinyl acetoacetal, and acrylic polyol, and polyisocyanate, and a lubricant such as phosphoric acid ester and silicone oil, and lubricating fine particles such as talc are added as necessary. You can The thickness of the heat resistant slipping layer is 5.0 μm or less, preferably 0.1 to 1.0.
A heat resistant slipping layer having sufficient performance can be formed with a thickness of μm.

The image-receiving sheet used for forming an image by using the above-mentioned thermal transfer sheet may be any one as long as its recording surface has a dye-accepting property to the above-mentioned dye, and Paper, metal, which does not have dye receptivity
In the case of glass or synthetic resin, a dye receiving layer may be formed on at least one surface thereof. In the case of a heat-melting type heat transfer sheet, the material to be transferred is not particularly limited, and may be ordinary paper or a plastic film.
A known thermal transfer printer can be used as it is as a printer used when performing thermal transfer using the thermal transfer sheet and the image receiving sheet as described above, and is not particularly limited.

[0020]

EXAMPLES Next, the present invention will be described more specifically with reference to Examples and Comparative Examples. In the text, parts and% are based on weight unless otherwise specified. Example 1 A polyester film having a thickness of 6.0 μm (manufactured by Toray, 6CF)
53) A polyester primer layer is provided on one side, and the heat resistant slipping layer ink having the following composition is applied to that side by a gravure coater and dried under the conditions of a drying temperature of 100 to 110 ° C. and a residence time in a drying hood of 10 seconds. To form a heat resistant slipping layer. Ink composition : Polyvinyl butyral resin (Sekisui Chemical Co., Ltd., S-REC BX-1) 2.2 parts Toluene 35.4 parts Methyl ethyl ketone 53.0 parts Isocyanate (Dainippon Ink and Chemicals, Vernock D-750) 6.8 parts Phosphoric ester ( Dai-ichi Kogyo Seiyaku, Prysurf A-208s) 1.6 parts Phosphate ester sodium salt (Toho Kagaku, Gafac RD720) 0.6 parts Talc (Nippon Talc, Microace L-1) 0.4 parts Amine -Based catalyst (Sumitomo Bayer Urethane, Desmorapid PP) 0.02 parts

The above film was cured by heating in an oven at 60 ° C. for 3 days. The amount of ink applied after drying was about 1.2 g / m ² . Next, a polyester primer layer is provided on the surface of the film opposite to the heat resistant slipping layer, and an antistatic layer ink having the following composition is applied to that surface so that the dry coating amount is 0.2 g / m ² And was dried under the conditions of a drying temperature of 100 to 110 ° C. and a residence time in the drying hood of 10 seconds to form an antistatic layer. Ink composition : Acrylic resin solution (Bondip P main agent, manufactured by Konishi Bond) 1.5 parts Epoxy resin solution (Bondip P curing agent, manufactured by Konishi Bond) 1.5 parts Isopropyl alcohol 66.6 parts Water 33.3 parts

Further, three color dye layer-forming inks having the following compositions were applied on the antistatic layer in a frame-sequential manner by a gravure coater so that the thickness when dried was 1.2 g / m ² , and the drying temperature was set. A thermal transfer sheet of the present invention was obtained by drying under the conditions of 100 to 110 ° C. and a residence time in a dry hood of 30 seconds to form a dye layer (see FIG. 1a). Yellow ink composition : Holon Brilliant Yellow (manufactured by Sand Co.) 3.0 parts Polyvinyl butyral resin (Sekisui Chemical Co., Ltd., S-REC BX-1) 4.0 parts Methyl ethyl ketone 46.5 parts Toluene 46.5 parts Magenta ink composition : MS Red G (Manufactured by Mitsui Toatsu) 2.4 parts Macrolex RVR (manufactured by Bayer) 1.2 parts Polyvinyl butyral resin (manufactured by Sekisui Chemical Co., Ltd., S-REC BX-1) 4.0 parts Methyl ethyl ketone 46.2 parts Toluene 46.2 parts Cyan Ink composition : Kayaset Blue 714 (manufactured by Nippon Kayaku) 4.0 parts Polyvinyl butyral resin (Sekisui Chemical Co., Ltd., S-REC BX-1) 4.0 parts Methyl ethyl ketone 46.0 parts Toluene 46.0 parts

Example 2 6.0 μm-thick polyester film (manufactured by Toray, 6CF)
53) A polyester primer layer is provided on one surface, the antistatic layer is formed on that surface, the heat resistant slip layer is formed thereon, and then polyester is formed on the surface opposite to the heat resistant slip layer. A thermal transfer sheet of the present invention was obtained in the same manner as in Example 1, except that a system primer layer was provided, and the dye layer-forming inks of the above-mentioned compositions of three colors were respectively applied face-sequentially thereto (see FIG. 1b). .

Example 3 A thermal transfer sheet of the present invention was obtained in the same manner as in Example 1 except that the polyester primer layer was not provided on the dye layer side (see FIG. 1c). Example 4 A thermal transfer sheet of the present invention was obtained in the same manner as in Example 2 except that the polyester primer layer was not provided on the heat resistant slipping layer side (see FIG. 1d). Comparative Example 1 A thermal transfer sheet of the present invention was obtained in the same manner as in Example 1 except that the antistatic layer was not provided.

Evaluation Examples Using the thermal transfer sheets of the above-mentioned Examples and Comparative Examples, a video printer VY-25 (manufactured by Hitachi, Ltd.) was used, and 5 sheets of dark solid printing of yellow, magenta and cyan were printed on the image receiving sheet dedicated to the printer. A result of 1 was obtained. Table 1 The number in the parentheses indicates (the number of defective sheets / the number of printed sheets).

[0026]

According to the present invention as described above, the antistatic layer of the thermal transfer sheet is formed of an antistatic resin composed of an acrylic resin and an epoxy resin, so that the antistatic property is excellent and the thermal transferable color material layer and the heat resistant layer It is possible to provide a thermal transfer sheet having excellent adhesion of the slippery layer to the base film.

[0027]

[Brief description of drawings]

FIG. 1 is a diagram illustrating a layer structure of a thermal transfer sheet of the present invention.

[Explanation of symbols]

 1: Substrate film 2: Thermal transfer color material layer 3: Antistatic layer 4: Primer layer 5: Heat resistant slipping layer

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification number Office reference number FI technical display location 7267-2H B41M 5/26 J 7267-2H 101 F 7267-2H 101 J

Claims (6)

[Claims] 1. A heat transferable color material layer and an antistatic layer are formed on a substrate film, and the antistatic layer is made of an antistatic resin composed of an acrylic resin and an epoxy resin. Thermal transfer sheet. 2. The thermal transfer sheet according to claim 1, wherein the antistatic resin has adhesiveness. 3. The thermal transfer sheet according to claim 1, wherein the antistatic layer is formed between the base film and the thermal transfer color material layer. 4. The thermal transfer sheet according to claim 1, wherein the antistatic layer is formed between the heat resistant slipping layer and the base film. 5. The acrylic resin is a copolymer of an acrylic monomer having a quaternary ammonium group and an acrylic monomer having a group capable of reacting with an epoxy group.
The thermal transfer sheet described in. 6. The thermal transfer sheet according to claim 1, wherein the epoxy resin is a bisphenol type polyepoxy compound.