JPH06262864A - Thermal transfer sheet - Google Patents

Abstract

PURPOSE:To obtain a thermal transfer sheet excellent in the antistaining properties to other article and forming a sharp high density recording image by providing a dye layer containing a dye represented by a specific general formula on one surface of a base material sheet. CONSTITUTION:A dye represented by formula I and/or formula II is dissolved or dispersed in a proper solvent along with a binder such as ethyl cellulose to prepare a coating soln. for forming a dye layer. This coating soln. is applied to a base material sheet such as a polyester film and dried to form the dye layer to obtain a thermal transfer sheet. As a thermal transfer image receiving sheet used for forming an image using the obtained thermal transfer sheet, any one whose recording surface has dye receptivity to the above mentioned dye may be used. In the case of paper or a synthetic resin having no dye receptivity, a dye receiving layer may be formed on one surface thereof.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a thermal transfer sheet,
More specifically, it is an object of the present invention to provide a thermal transfer sheet which is excellent in stain resistance with respect to other articles and which is capable of forming a recorded image having high density and high sharpness and various fastnesses.

[0002]

2. Description of the Related Art Conventionally, various sublimation-type thermal transfer methods have been known, and in recent years, due to advances in recording methods, a thermal head or the like has been used to provide a dye receiving layer on a polyester sheet or paper at high speed. Using a thermal transfer image receiving sheet,
Delicate characters and figures or full-color photographic images can be formed on these thermal transfer image-receiving sheets.

[0003]

DISCLOSURE OF THE INVENTION Problems to be Solved by the Invention In the above-mentioned prior art, since the heating time at the time of thermal transfer by the thermal head is extremely short, the dye used in the thermal transfer sheet has excellent sublimability, that is, heat transferability, Coloring and sharpness are required. Various dyes have been proposed to meet these requirements, but dyes excellent in heat transferability, color density and vividness are generally dyes having a relatively low molecular weight, and thermal transfer using these dyes is performed. When the sheet is formed, the dye in the dye layer of the thermal transfer sheet is apt to move, so that the dye migrates to the surface of the dye layer during storage of the thermal transfer sheet, and when the migrated dye touches another article, it contaminates the other article. There is a problem.

As a method for solving such a problem,
It has been proposed to use a dye having a relatively high molecular weight, for example, a dye having an aromatic ring introduced in addition to the basic skeleton of the dye, but in the case of these relatively high molecular weight dyes, stain resistance However, the solubility in methyl ethyl ketone, toluene, or a mixture thereof is low, so that even if a dye layer is formed, the concentration of the dye present in the dye layer is low, and a clear image with high density can be obtained. There is a problem that it is not formed. Therefore, an object of the present invention is to provide a thermal transfer sheet which is excellent in stain resistance with respect to other articles and which can form a recorded image having high density and high sharpness and excellent various fastnesses.

[0005]

The above object can be achieved by the present invention described below. That is, the present invention comprises a substrate sheet and a dye layer formed on one surface of the substrate sheet,
The thermal transfer sheet is characterized in that the dye contained in the dye layer is a dye represented by the following formula (1) and / or (2).

[Chemical 2]

[0006]

The dyes of the above formulas (1) and (2) are known in the general formula of JP-A-5-585, but among the general formulas described in the above-mentioned JP-A-5-585. In the above, only the specific dye has excellent solvent solubility as compared with other dyes despite having the same basic structure, and when used for a thermal transfer sheet, while maintaining stain resistance, It has been found that a recorded image having high density and vividness and excellent in various fastnesses can be easily applied to the thermal transfer image-receiving sheet.

[0007]

BEST MODE FOR CARRYING OUT THE INVENTION Next, the present invention will be described in more detail with reference to preferred embodiments. The dye of the above formula (1) or (2) used in the present invention is

[Chemical 3] The hydrogen atom bonded to the nitrogen atom of benz [cd] indole-2- (1H) one represented by is substituted with a cyclohexylpropyl group or a (3-methyl) phenoxypropyl group, and then dehydrated and condensed with dicyanomethylene. It can be manufactured by a known method such as a method of performing.

The thermal transfer sheet of the present invention is characterized by using the dyes of the above formulas (1) and / or (2), and other constitutions may be the same as those of the conventionally known thermal transfer sheet. Further, in the present invention, known yellow dyes, magenta dyes, and cyan dyes may be mixed with the above specific dyes in order to adjust the hue, and generally, a diarylmethane type, a triarylmethane type, a thiazole type, Methocyanins such as merocyanine, indoaniline, acetophenone azomethine, pyrazoloazomethine, imidazole azomethine, imidazoazomethine, azomethine typified by pyridone azomethine, xanthine, oxazine, dicyanostyrene,
Cyanomethylene series such as tricyanostyrene, thiazine series, azine series, acridine series, benzeneazo series,
Pyridone azo, thiophene azo, isothiazole azo,
Heterocyclic azo type represented by pyrrole azo, pyrazole azo, imidazole azo, thiadiazole azo, triazole azo, disazo, spiro dipyran type, indolino spiro pyran type, fluorane type, rhodamine lactam type,
Dyes such as naphthoquinone type, anthraquinone type, and quinophthalone type are representative, and specifically, the following dyes can be preferably used.

C. I. (Color Index) Yellow 51, 3, 54, 79, 60, 23, 7, 141,
201, 231, C.I. I. Disperse Blue 24, 5
6, 14, 301, 334, 165, 19, 72, 8
7, 287, 154, 26, 354; C.I. I. Disperse Thread 135, 146, 59, 1, 73, 60, 1
67; C.I. I. Disperse Violet 4, 13, 2
6, 36, 56, 31, Disperse Orange 149;
C. I. Solvent Violet 13; C.I. I. Solvent Black 3; C.I. I. Solvent Green 3; C.I.
I. Solvent Yellow 56, 14, 16, 29; C.I.
I. Solvent Blue 70, 35, 63, 36, 50,
49, 111, 105, 97, 11; C.I. I. Solvent Red 135, 81, 18, 25, 19, 23, 2
4, 143, 146, 182, etc.

More specifically, for example, 3,3'-diethyloxathiacyanine iodide astrazone pink FG (manufactured by Bayer, CI48015),
2,2'-carbocyanine (C.I.808), Astraphylloxin FF (C.I.48070), Astrazone Yellow 7GLL (C.I. Basic Yellow 21), Eisen Catillon Elo 3GLH (Hodogaya Kagaku) C.I.48055), Eisen Catillon Red 6BH (C.I.48020), and other methine (cyanine) basic dyes such as monomethine, dimethine, or trimethine; auramine (C.I.655). ) And the like diphenylmethane-based basic dyes; malachite
Green (C.I. 42000), Brilliant Green (C.I. 42040), Magenta (C.I. 4)
2510), metal violet (C.I.
5), crystal violet (C.I.
5), methyl green (C.I.684), Victoria Blue B (C.I.44045) and other triphenylmethane-based basic dyes; Pyronin G (C.I.739),
Rhodamine B (C.I.45170), Rhodamine 6G
(C.I.45160) and other xanthene-based basic dyes;
Acridine Yellow G (C.I.785), Leonine AL (C.I.46075), Benzoflavin (C.I.
I. 791), Affine (CI.46045) and other acridine-based basic dyes; Neutral Red (C.I.
I. 50040), Astrazone Blue BGE / x
125% (CI.51005), methylene blue (CI.52015) and other quinone imine-based basic dyes; and other basic dyes such as anthraquinone-based basic dyes having a quaternary ammonium group .

As cyan dyes, Kayaset Blue 714 (Nippon Kayaku, Solvent Blue 63), Foron Brilliant Blue SR (Sand, Disperse Blue 354), Waxolin AP-FW (ICI, Solvent Blue) 36), as a magenta dye, MS-R
EDG (manufactured by Mitsui Toatsu, Disperse Red 60), Macrolex Red Vio Red R (manufactured by Bayer, Disperse Violet 26), as yellow dye, Foron Brilliant Yellow S-6GL (manufactured by Sand, Disperse Yellow 231), macro Rex yellow 6
G (manufactured by Bayer, Disperse Yellow 201), and those having the following structural formulas are also included.

[0012]

[Chemical 4]

These dyes can be used in the form as they are, or in the form obtained by treating these dyes with an alkali, and a counter ion exchanger or leuco form of these dyes can also be used. When a leuco dye or the like, which is normally colorless or light-colored, is used, it may be incorporated in the developer on the thermal transfer image-receiving sheet. Also, JP-A-59-78895
No. 60, No. 60-28451, No. 60-28453, No. 60-53564, No. 61-148096, No. 60.
-239290, 60-31565, 60-3
0393, 60-53565, 60-2759.
No. 4, No. 61-262191, No. 60-152563.
No. 61-244595 and No. 62-196186.
And sublimation yellow dyes described in International Publication WO92 / 05032, Nos. 60-223862 and 60-284.
No. 52, No. 60-31563, No. 59-78896.
No. 60, No. 60-31564, No. 60-30391, No. 61-227092, No. 61-227091, No. 6
0-30392, 60-30394, 60-1
31293, 61-227093, 60-15.
9091, 61-262190, U.S. Pat.
98,651 and Japanese Patent Application No. 62-220793, U.S. Pat. No. 5,079,365, sublimable magenta dyes, JP-A-59-78894 and 59-227490.
No. 60, No. 60-151098, No. 59-227493.
No. 61-244594, No. 59-227948.
No. 60-131292, No. 60-172591.
No. 60-151097, No. 60-131294
No. 60, No. 60-217266, No. 60-31559,
No. 60-53563, No. 61-255897, No. 6
0-239289, 61-29293, 61-
19396, 61-268493, 61-35.
No. 994, No. 61-31467, No. 61-14826.
No. 9, No. 61-49893, No. 61-57651,
No. 60-239291, No. 60-239292, No. 61-284489, No. 62-191191 and Japanese Patent Application No. 62-176625, US Pat. No. 5,079,3.
Sublimation cyan dyes described in publications such as No. 65 and the specification are also preferably used.

Other dyes include dyes represented by the following formula.

[Chemical 5]

[0015]

[Chemical 6]

[0016]

[Chemical 7]

[0017]

[Chemical 8]

[0018]

[Chemical 9]

In the above general formula, R, X and Y represent the following substituents. R ₁ and R _{2 A} substituted or unsubstituted alkyl group, a substituted or unsubstituted cycloalkyl group or a substituted or unsubstituted aralkyl group. R ₃ substituted or unsubstituted alkyl group, substituted or unsubstituted alkoxy group, substituted or unsubstituted alkylcarbonylamino group, substituted or unsubstituted alkylsulfonylamino group, substituted or unsubstituted alkylaminocarbonyl group, substituted or An unsubstituted alkylaminosulfonyl group or a halogen atom. R ₄ substituted or unsubstituted alkoxycarbonyl group, substituted or unsubstituted alkylaminocarbonyl group, substituted or unsubstituted alkoxy group, substituted or unsubstituted alkyl group, substituted or unsubstituted cycloalkyl group, heterocyclic group or Halogen atom. R ₅ substituted or unsubstituted alkyl group, substituted or unsubstituted alkoxycarbonyl group, substituted or unsubstituted alkylaminocarbonyl group, substituted or unsubstituted alkoxy group, substituted or unsubstituted alkylaminosulfonyl group, substituted or non-substituted Substituted cycloalkyl group, cyano group, nitro group, halogen atom or hydrogen atom.

R _{6 A} substituted or unsubstituted alkyl group, a substituted or unsubstituted aryl group, a substituted or unsubstituted amino group, a substituted or unsubstituted cycloalkyl group, a cyano group, a nitro group or a halogen atom. R _{7 A} substituted or unsubstituted alkyl group, a substituted or unsubstituted amino group, a substituted or unsubstituted alkoxy group, a substituted or unsubstituted alkoxycarbonyl group or a halogen atom. R _{8 A} substituted or unsubstituted aryl group, aromatic heterocyclic group, cyano group, nitro group, halogen atom or other electron withdrawing group. R ₉ CONHR ₁₀ , SO ₂ NHR ₁₀ , NHCOR ₁₁ ,
NHSO ₂ R ₁₁ or a halogen atom. R _{10 A} substituted or unsubstituted alkyl group, a substituted or unsubstituted cycloalkyl group, a substituted or unsubstituted aryl group or a substituted or unsubstituted aromatic heterocyclic group.

R _{11 A} substituted or unsubstituted alkyl group, a substituted or unsubstituted cycloalkyl group, a substituted or unsubstituted amino group, a substituted or unsubstituted aryl group, or a substituted or unsubstituted aromatic heterocyclic group. R _{12 A} substituted or unsubstituted alkyl group. R ₁₃ amino group or hydroxyl group. X halogen atom. A Y- substituted or unsubstituted aryl group, a substituted or unsubstituted aromatic heterocyclic group.

The substrate sheet used for the thermal transfer sheet of the present invention may be any one as long as it has a conventionally known degree of heat resistance and strength, for example, 0.5.
Paper having a thickness of about 50 μm, preferably about 3 to 10 μm,
Various processed papers, polyester films, polystyrene films, polypropylene films, polysulfone films, polycarbonate films, aramid films, polyvinyl alcohol films, cellophane, etc., and particularly preferred are polyester films.

The dye layer provided on the surface of the substrate sheet as described above is a layer in which the dye is carried by an arbitrary binder resin. As the binder resin for supporting the above-mentioned dye, any conventionally known one can be used,
Preferred examples include ethyl cellulose, hydroxyethyl cellulose, ethyl hydroxycellulose,
Hydroxypropyl cellulose, ethyl hydroxyethyl cellulose, methyl cellulose, cellulose acetate, cellulose acetate butyrate, cellulose acetate propionate, cellulose resins such as cellulose nitrate, polyvinyl alcohol, polyvinyl acetate, polyvinyl butyral, polyvinyl acetoacetal, polyvinyl pyrrolidone, polystyrene, poly Vinyl resin such as vinyl chloride, acrylic resin such as polyacrylonitrile, polyacrylic acid ester,
Examples thereof include polyamide resin, polyester resin, polycarbonate resin, phenoxy resin, phenol resin, epoxy resin, and elastomer, and these may be mixed or copolymerized and used. Further, various curing agents may be added. Of these, polyvinyl butyral and polyvinyl acetal are particularly preferable from the viewpoints of heat resistance and dye migration. The dye layer of the thermal transfer sheet of the present invention,
Basically, it is formed from the above-mentioned materials, but if necessary, various additives similar to those conventionally known can be included.

Such a dye layer is preferably prepared by adding the above-mentioned dye, binder resin and other optional components to an appropriate solvent to dissolve or disperse each component to prepare a dye layer-forming coating liquid or ink. This is applied and dried on the above-mentioned substrate sheet to form. The dye layer thus formed is
The thickness is about 0.2 to 5.0 μm, preferably 0.4 to 2.0 μm, and the dye in the dye layer is 5 to 70% by weight, preferably 10 to 10% by weight of the dye layer. 60% by weight
Is preferably present in an amount of. The thermal transfer sheet of the present invention as described above is sufficiently useful as it is for thermal transfer, but an anti-adhesion layer, that is, a release layer may be further provided on the surface of the dye layer, and by providing such a layer. It is possible to prevent the heat transfer sheet and the heat transfer image-receiving sheet from sticking to each other during heat transfer, and to use an even higher heat transfer temperature to form an image with more excellent density.

As the release layer, even if only the adhesion-preventing inorganic powder is attached, a considerable effect is exhibited.
For example, from a resin having excellent releasability such as a silicone polymer, an acrylic polymer, or a fluorinated polymer, 0.01 to
It can be formed by providing a release layer having a thickness of 5 μm, preferably 0.05 to 2 μm. The inorganic powder or releasable polymer as described above can exert a sufficient effect even when incorporated in the dye layer. Further, a heat-resistant layer may be provided on the back surface of such a thermal transfer sheet in order to prevent adverse effects due to the heat of the thermal head. The thermal transfer image-receiving sheet used for forming an image using the thermal transfer sheet as described above may be any one as long as its recording surface has dye receptivity to the dye, In the case of paper, metal, glass, synthetic resin or the like having no property, a dye receiving layer may be formed on at least one surface thereof.

Examples of the thermal transfer image-receiving sheet which does not require the formation of a dye receiving layer include polyolefin resins such as polypropylene, halogenated polymers such as polyvinyl chloride and polyvinylidene chloride, polyvinyl acetate and polyacrylic ester. Polyester resins such as vinyl polymers, polyethylene terephthalate, polybutylene terephthalate, polystyrene resins, polyamide resins, copolymer resins of olefins such as ethylene and propylene with other vinyl monomers, ionomers, cellulose diacetate, etc. Examples thereof include fibers made of resin and polycarbonate, woven fabrics, films, sheets, molded products and the like. Particularly preferred is a sheet or film made of polyester or a processed paper provided with a polyester layer. Even for non-dyeing thermal transfer image-receiving sheets such as paper, metal, glass, etc., a solution or dispersion of the above-mentioned dyeing resin is applied to the recording surface and dried, or those resins are also applied. By laminating the film, a thermal transfer image-receiving sheet can be obtained.

Further, even in the case of the thermal transfer image-receiving sheet having the above-mentioned dyeing property, a resin having a further dyeing property on the surface thereof,
The dye receiving layer may be formed as in the above paper. The dye-receptive layer thus formed may be formed of a single material or a plurality of materials, and may further contain various additives within the range not impairing the intended purpose. Is natural. Such a dye receiving layer may have any thickness, but is generally 3 to 50 μm thick. Further, such a dye receiving layer is preferably a continuous coating, but it may be formed as a discontinuous coating by using a resin emulsion or a resin dispersion. Such a thermal transfer image-receiving sheet is basically as described above and can be used satisfactorily as it is. However, the thermal transfer image-receiving sheet or its dye receiving layer contains an inorganic powder for preventing adhesion. By doing so, even if the temperature at the time of thermal transfer is raised, adhesion between the thermal transfer sheet and the thermal transfer image-receiving sheet can be prevented, and more excellent thermal transfer can be performed. Particularly preferred is finely divided silica.

Further, in place of or in combination with the above-mentioned inorganic powder such as silica, a resin having good releasability as described above may be added. Particularly preferable releasing polymer is a cured product of a silicone compound, for example, a cured product of an epoxy-modified silicone oil and an amino-modified silicone oil. Such a release agent is preferably contained in an amount of about 0.5 to 30% by weight based on the weight of the dye receiving layer. The thermal transfer image-receiving sheet to be used may have the above-mentioned inorganic powder adhered to the surface of the dye-receiving layer to enhance the anti-adhesion effect, and the above-mentioned release having excellent releasability. You may provide the layer which consists of agents. Such a release layer exerts a sufficient effect with a thickness of about 0.01 to 5 μm, and can prevent the adhesion of the thermal transfer sheet to the dye receiving layer and further improve the dye receiving property.

As the means for applying thermal energy used when performing thermal transfer using the thermal transfer sheet of the present invention as described above and the recording material as described above, any conventionally known applying means can be used. By controlling the recording time with a recording device such as a printer (for example, Hitachi, video printer VY-100), 5 to 5
By applying heat energy of about 100 mJ / mm ² , the intended purpose can be sufficiently achieved.

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 A dye layer-forming ink composition having the following composition was prepared, and applied to a 6 μm-thick polyethylene terephthalate film having a heat-treated back surface so that the dry coating amount was 1.0 g / m ² and dried. A thermal transfer sheet of the present invention was obtained. Dye of the formula (1) or (2) 3 parts Polyvinyl butyral resin 4.5 parts Methyl ethyl ketone 46.25 parts Toluene 46.25 parts However, when the dye is insoluble in the solvent in the above composition, DMF as a solvent, Dioxane, chloroform, etc. were used appropriately.

Comparative Example Instead of the dye of Example 1, the substituent R has the following basic structure.
Was used in the same manner as in Example 1 except that the dyes shown in Table 1 were used to prepare a thermal transfer sheet of Comparative Example.

[Chemical 10]

[0031]

[Table 1]

Next, a synthetic paper (Yupo FPG # 150, manufactured by Oji Yuka) was used as a base sheet, and a coating solution having the following composition was applied to one surface thereof at a rate of 10.0 g / m ² when dried. And then dried at 100 ° C. for 30 minutes to obtain a thermal transfer image-receiving sheet. Polyester resin (Vylon200, Toyobo) 11.5 parts Vinyl chloride / vinyl acetate copolymer (VYHH, UCC) 5.0 parts Amino-modified silicone (KF-393, Shin-Etsu Chemical Co., Ltd.) 1.2 parts Epoxy-modified Silly Corn (X-22-343, manufactured by Shin-Etsu Chemical Co., Ltd.) 1.2 parts Methyl ethyl ketone / toluene / cyclohexanone (weight ratio 4: 4: 2) 102.0 parts

The thermal transfer sheet of the present invention and the thermal transfer sheet of the comparative example, and the thermal transfer image-receiving sheet described above are overlapped with their respective dye layers and dye-receiving surfaces facing each other, and the head applied voltage is applied from the back surface of the thermal transfer sheet. 11V, printing time 16m
sec. Recording was performed with a thermal head under the conditions of. Evaluation method of stain resistance : The image surface obtained by the above-mentioned recording and a synthetic paper (Yupo FPG # 150, manufactured by Oji Yuka Co., Ltd.) were overlaid, and 40 hours passed under a load of 20 g / cm ² and 60 ° C. Then, the degree of contamination of the synthetic paper was evaluated according to the following criteria. ○: No pollution or slight pollution. ×: Remarkably contaminated. Image Density Evaluation Method : The maximum image density of the image obtained by the above recording is determined by the Densidometer TR of X-Rite, Inc. of the United States.
It was measured at -310. Dye solubility evaluation method : After the prepared ink composition for forming a dye layer was allowed to stand at 30 ° C. for 4 hours, dye deposition was observed as x, and dye deposition was not marked as o.

[0034]

According to the present invention as described above, the dyes represented by the formulas (1) and / or (2) have the general formula of JP-A-5-58.
A dye known in JP-A No.
In the general formula described in Japanese Patent No. 585, only the specific dye described above has excellent solvent solubility as compared with other dyes even though it has the same basic structure, and was used for a thermal transfer sheet. In this case, it is possible to easily give a recorded image having high density and vividness and excellent in various fastnesses to the thermal transfer image receiving sheet while maintaining the stain resistance.

Claims (1)

[Claims] 1. A substrate sheet and a dye layer formed on one surface of the substrate sheet, wherein the dye contained in the dye layer is represented by the following formula (1) and / or (2). A thermal transfer sheet characterized by being a dye. [Chemical 1]