JP2815419B2 - Magenta color thermal sublimation transfer sheet - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention provides a magenta color heat-sensitive sublimation transfer sheet for a heat-sensitive sublimation transfer system.

More specifically, in a method of sublimating and transferring onto an image receiving paper by heating with a heating element such as a thermal head to obtain a color copy with good gradation, it has good dyeing and coloring properties and fastness. The present invention relates to a transfer sheet from which an excellent color copy can be obtained.

[Conventional technology]

In the thermal sublimation transfer system, a thermal transfer sheet coated with an ink containing a dye for thermal transfer is superimposed on an image receiving paper and heated and pressed with a thermal head, and the dye sublimates and transfers to the image receiving paper, producing a full-color copy with good gradation. It is a system that can be obtained.

The first feature of the thermal sublimation recording method is that a thermal head is mainly used as a hardware device,
Compact, excellent in maintainability and reliability. Secondly, since it is possible to obtain a mixed color image at a molecular level, a recording similar to a silver halide color photograph having excellent gradation and reproducibility can be obtained.

Further, this system has been applied as a wide variety of full-color recording systems such as CG (computer graphics), plate making systems, video movies, still video systems, and prepaid cards, and has recently received particular attention.

More specifically, a method is used in which a transfer sheet coated with a sublimable dye is heated by a thermal head controlled by a color signal of a still image to transfer and record the dye on an image receiving paper. , Magenta and cyan. Furthermore, in order to provide light and dark, four primary colors may be used by adding black to the above three primary colors.

[Problems to be solved by the invention]

The following conditions are required as the quality required for the magenta color heat-sensitive sublimation transfer sheet.

Good compatibility or solubility of the dye with the solvent and the binder resin in the ink used when applying to the transfer sheet.

The energy required for sublimation dyeing from the transfer sheet to the receiving paper is as low as possible, and an image with color value is obtained on the receiving paper.

The transferred image is a magenta color, which is one of the so-called three primary colors of printing, and has little turbidity.

The dye in the transfer sheet does not recrystallize even when heated or humidified.

Good light fastness and storage stability of the transferred image.

Among the above conditions, what is particularly required is that the ink has a high solubility in a solvent and a good compatibility with a binder resin. That is, in the thermal sublimation transfer system, the dye must be completely dissolved in the binder resin on the transfer sheet in order to sublime at the molecular level. If the dye is transferred in a state of being insoluble in the binder resin on the transfer sheet, a uniform image cannot be obtained, and the image density is low,
Remarkably inferior in commercial value.

Although development is underway to satisfy all the conditions necessary for the above transfer sheet, dyes with good sublimability are currently under further improvement due to poor durability and poor storage stability. Is desired.

[Means for solving the problem]

Means for Solving the Problems The present inventors have conducted intensive studies as a means for solving the above problems, and have developed a transfer sheet containing a magenta-based compounded dye that satisfies all of the above conditions and completed the present invention.

That is, in the present invention, general formula (I) (In the formula, R ₁ represents an alkyl group, an alkoxy group, an alkoxyalkyl group, and a halogen atom.) And the general formula (II) (In the formula, R ₂ represents a hydrogen atom, an alkyl group, an alkoxy group, an alkoxyalkyl group, and a halogen atom.)
Surprisingly, it has been found that a transfer sheet that satisfies all of the above conditions can be obtained.

Specific examples of R ₁ and R _{2 in} the general formulas (I) and (II) include a methyl group, an ethyl group, and an isopropyl group as an alkyl group, and a methoxy group, an ethoxy group, and a propoxy group as an alkoxy group. Examples of the alkoxyalkyl group include a methoxyethyl group and an ethoxyethyl group, and examples of the halogen atom include a fluorine atom, a chlorine atom, and a bromine atom.

R ₁ in the general formula (I) and R _{2 in the} general formula (II) are particularly preferably in the m-position in view of solubility. Further, the mixing ratio is arbitrary because it is determined by color matching to magenta.

JP-A-64-77584 discloses that, in place of the general formula (I), the general formula (A) (Wherein X represents a hydrogen atom, a halogen atom, a trifluoromethyl group, an alkyl group, or an alkoxy group) and a transfer sheet containing the dye represented by the general formula (II). ing. The dye represented by the general formula (A) has the same substituents on the phenoxy group at the 2-position and the 3-position of anthraquinone, and when X is a hydrogen atom, has low solubility in a solvent. No improvement in solubility due to blending with II) is also observed. X is a halogen atom, a trifluoromethyl group,
In the case of an alkyl group or an alkoxy group, the solubility in a solvent is improved, but the above condition cannot be satisfied because the molecular weight is larger than that of the general formula (I) and the sublimation speed is inferior.

However, in the present invention, the dye represented by the general formula (I) is a violet color dye having a good solubility in a solvent and a good sublimation speed because it has a substituent only at the 2-position phenoxy group of anthraquinone. The synergistic effect of combining one or more of these with one or more red dyes represented by the general formula (II) further enhances solubility in solvents and binder resins, and sublimation speed, color value, saturation, and light resistance It has become possible to provide a transfer sheet that satisfies all of the above-mentioned conditions (1) and (2) such as storage stability. Furthermore, good results can be obtained by adding other magenta dyes to the above combination.

As a method of manufacturing a transfer sheet, a thermal transfer recording ink composed of a dye, a binder resin, and a solvent is applied on a transfer sheet base material to prepare a transfer sheet.

As the resin for preparing the thermal transfer recording ink, those used in ordinary printing inks may be used, such as rosin, phenol, xylene, petroleum, vinyl, polyamide, nitrocellulose, and alkyl celluloses. Or an aqueous resin such as maleic acid, acrylic acid, casein, shellac and glue.

Examples of the solvent for ink preparation include alcohols such as methanol, ethanol, propanol and butanol, cellosolves such as methyl cellosolve and ethyl cellosolve, aromatics such as benzene, toluene and xylene, ethyl acetate and butyl acetate. And ketones such as acetone, methyl ethyl ketone and cyclohexanone, and hydrocarbons such as ligroin, cyclohexane and kerosene.

As the base material of the transfer sheet to which the ink is applied, thin paper such as condenser paper and glassine paper, and a plastic film with good heat resistance such as polyester, polyamide and polyimide are suitable, but these base materials are obtained from the thermal head. 2-20μm to improve heat transfer efficiency to dye
A moderate thickness is appropriate.

Further, as the recording material, for example, polyethylene, polyolefin resin such as polypropylene, polyvinyl chloride, halogenated polymer such as polyvinylidene chloride, polyvinyl alcohol, polyvinyl acetate, vinyl polymer such as polyacrylester, polyethylene terephthalate, Polyester resin such as polybutylene terephthalate, polystyrene resin, polyamide resin, copolymer resin of olefin such as ethylene and propylene and other vinyl monomers, ionomer, cellulose diacetate, cellulose resin, polycarbonate, polysulfone, polyimide, etc. , A woven fabric, a film, a sheet, a molded product, and the like.

Particularly preferred is a sheet or film made of polyethylene terephthalate.

The dye represented by the general formula (I) is, for example, a chemical equivalent of 1,4-diamino-2,3-dichloroanthraquinone in the general formula (III) (Wherein, R ₁ has the same meaning as in the general formula (I).) The phenol represented by the general formula (I) is reacted by heating at 140 to 160 ° C. in an aprotic polar solvent such as fluholane or dimethyl sulfoxide. Formula (IV) (Wherein R ₁ has the same meaning as in the general formula (I)), and then the compound represented by the general formula (IV) and phenol is reacted in an aprotic polar solvent in the same manner as in formula (IV). It can be obtained by reacting by heating at 180 ° C.

Dyes represented by the general formula (II) are described in, for example,
Similarly to the method disclosed in 61-227093, it can be obtained by reacting 1-amino-2-bromo-4-hydroxyanthraquinone with phenols.

[Action and effect]

The magenta color sublimation transfer sheet of the present invention containing one or more dyes represented by the general formula (I) and one or more dyes represented by the general formula (II) has a solubility of the compounded dye in a solvent and a binder resin. Is good, the storage stability of the dye in the binder resin on the sheet is good.

Further, the transfer sheet of the present invention has a good sublimation speed by heating the thermal head, and the hue transferred to the image receiving paper is a magenta color of the three primary colors of printing, is less turbid, and has a high color value.

Further, the transferred image receiving paper has very good light fastness and storage stability, and is a practically useful magenta color sublimation transfer sheet.

〔Example〕

Hereinafter, the present invention will be described in detail with reference to Examples. In the examples, "parts" represents weight.

Example 1 (1) Preparation method of ink 1,4-diamino-2-phenoxy-3- (3-methylphenoxy) -anthraquinone 0.9 part 1-amino-2- (3-methylphenoxy) -4-hydroxyanthraquinone 2.1 Part 4.5 parts of polybutyral resin 46.25 parts of methyl ethyl ketone 46.25 parts of toluene The ink was prepared by mixing the pigment mixture of the above composition with glass beads using a paint conditioner for about 30 minutes.

(2) Transfer sheet preparation method Using a gravure proofing machine (plate depth 30 μm), apply the above ink to a 3.5 μm thick polyethylene terephthalate film with a heat-resistant backside applied so that the dry weight becomes 1.0 g / m ^2. Dried.

(3) Recording material preparation method Polyester resin 0.8 parts (Vylon103 Toyobo Tg = 47 ° C) EVA polymer plasticizer (Elvaloy 741p Mitsui / Dupont Polychemical Tg =-
(32 ° C) 0.2 parts Amino-modified silicone 0.04 parts (KF-857 Shin-Etsu Chemical Co., Ltd.) Epoxy-modified silicone 0.04 parts (KF-103 Shin-Etsu Chemical Co., Ltd.) Methyl ethyl ketone / toluene / cyclohexane 9.0 parts (weight ratio 4: 4: 2) , A coating solution was prepared, and a bar coater (RK. Print Coat Instru) was applied to synthetic paper (Yoji FPG # 150 manufactured by Oji Yuka).
It was prepared by applying at a rate of 4.5 g / m ² when dried using No. 1 manufactured by ments Co., Ltd. and drying at 100 ° C. for 15 minutes.

(4) Transfer Recording The transfer sheet and the recording material are overlapped with their respective ink-coated surfaces and coating liquid-coated surfaces facing each other.
Recording was performed under the condition of 0 millisecond, and a magenta color record having a color density of 2.1 was obtained. Color densities were measured by a densitometer manufactured by Macbeth, USA.
It measured using RD-918. A xenon fedometer (manufactured by Suga Test Instruments Co., Ltd.) was used as a light resistance tester for the obtained recording at a black panel temperature of 63 ± 2 ° C., but the color hardly changed after irradiation for 40 hours. The image stability under high temperature and high humidity was also excellent.

In addition, the obtained recorded image is set in an atmosphere of 50 ° C.
After standing for 48 hours, the sharpness of the image was not changed, the white paper was not colored, and the sharpness of the recorded image was good, as judged by the sharpness of the image and the coloring when the surface was rubbed with white paper. .

Examples 2 to 17 The transfer sheet and the recording material were prepared in the same manner as in Example 1 by using the dyes shown in Table 1 in place of the dyes used in Example 1, and transfer recording was performed. Magenta colors of the three primary colors of printing having the densities shown in Table 1 were obtained, and the fastness was excellent as in Example 1.

Comparative Example A transfer sheet and a recording material were prepared in the same manner as in Example 1, except that the dyes shown in Table 2 were used instead of the dyes used in Example 1, and transfer recording was performed.

In Comparative Examples 1 and 2, since the solubility of the dyes (A) and (C) was low, no improvement in solubility was observed even when the dyes (B) and (D) were blended, and the color density was low. .

In Comparative Example 3, although the solubility of the dye (E) was high, the sublimation speed was low and the color density was low because of the large molecular weight.

──────────────────────────────────────────────────続 き Continuing from the front page (72) Keisuke Takuma, Inventor 300, Hiraharacho, Omuta-shi, Fukuoka Examiner Isao Fujii (56) References JP-A-64-77584 (JP, A) JP-A-1-174489 (JP) JP-A-1-174490 (JP, A) JP-A-1-183584 (JP, A) JP-A-1-217465 (JP, A) (58) Fields investigated (Int. Cl. ⁶ , DB Name) B41M 5/38-5/40 CA (STN)

Claims (1)

(57) [Claims] 1. The compound of the general formula (I) (Wherein, R ₁ represents an alkyl group, an alkoxy group, an alkoxyalkyl group and a halogen atom), and one or more dyes represented by general formula (II) (Wherein, R ₂ represents a hydrogen atom, an alkyl group, an alkoxy group, an alkoxyalkyl group, and a halogen atom.) A magenta-color heat-sensitive sublimation transfer sheet containing at least one dye represented by the formula: .