JP2001058465A - Thermal transfer recording medium - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a recording medium having excellent transparency of a thin film by vapor-depositing an organic pigment to a vapor-deposited layer. SOLUTION: As a base material, a polyethylene terephthalate film of about 2 to 4 μm is preferred, and a sticking preventive layer is provided on its rear surface. To raise its transfer sensitivity, a release layer is provided between the material and a vapor-deposited heat resistant layer. The release layer is a layer made of a heat fusible material containing a resin having high releasability as a main component from a wax or the material. The heat resistant layer is a layer containing a thermoplastic resin (containing an elastomer) as a main body, and an ionomer resin or the like can be used. As an organic pigment used for the vapor-deposited layer, there is an organic pigment of a perylene, isoindoline or the like, and a single or two or more types are mixed for use. A vapor-depositing method is not particularly limited, and a thickness of the vapor-deposited layer is preferably about 50 to 200 nm. An adhesive layer contains an adhesive resin as a main component, and as its resin, a phenol resin or the like is used.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a thermal transfer recording medium that can be made thin.

[0002]

2. Description of the Related Art Heretofore, for a colored layer of a thermal transfer recording medium requiring transparency, an ink in which an organic pigment is dispersed in a binder agent composed of waxes or resins or an ink in which a dye is dissolved is used. Have been. However, the ink in which the organic pigment is dispersed has a large average particle size of the organic pigment.
Transparency is not sufficient, further improvement is desired, and further, there are drawbacks such as difficulty in thinning for the same reason. The ink in which the dye is dispersed has good transparency, but has a disadvantage that the heat resistance and the weather resistance of the obtained impression are inferior due to the structure of the dye.

[0003]

SUMMARY OF THE INVENTION The present invention is directed to a heat transfer recording medium which is thin and excellent in transparency while the demand for thinning the heat transfer recording medium is increasing in accordance with high definition of an image and power saving of the apparatus. The task is to provide

[0004]

SUMMARY OF THE INVENTION The present invention provides a method for manufacturing
The present invention relates to a thermal transfer recording medium provided with at least a vapor-deposited heat-resistant layer, a vapor-deposited layer, and an adhesive layer, wherein the vapor-deposited layer is a colored layer obtained by vapor-depositing an organic pigment.

[0005]

DESCRIPTION OF THE PREFERRED EMBODIMENTS In order to solve the above problems, the present invention is characterized in that a colored layer of a thermal transfer recording medium is formed by vapor deposition of an organic pigment. By depositing an organic pigment, a film having excellent transparency is formed, and a very thin film can be colored at a high concentration. Thus, a thermal transfer recording medium having a thin film, excellent transparency, and high reflection density can be obtained.

When such a thermal transfer recording medium is thermally transferred onto a receiver using an image forming apparatus such as a thermal transfer printer equipped with a thermal head, a high-quality multi-tone color image can be formed only by area tone. it can.

As the substrate used in the present invention, various film materials generally used as a substrate of this type of thermal transfer recording medium can be used. However, durability, heat transferability, high definition of printing, cost, etc. In view of the above, a polyethylene terephthalate film having a thickness of 2 to 6 μm, preferably 2 to 4 μm is preferred. It is preferable to provide a stick prevention layer on the back surface of the substrate to prevent sticking to the thermal head.

In the present invention, it is desirable to provide a release layer between the substrate and the heat-resistant layer for vapor deposition in order to increase the transfer sensitivity. The release layer used in the present invention is a layer made of a heat-fusible material containing wax or a resin having high releasability from a base material as a main component, and may further contain another heat-meltable resin as necessary. Examples of the wax include petroleum waxes such as polyethylene wax and microcrystalline wax, synthetic waxes such as oxidized wax and ester wax, and higher fatty acids. As the resin having high releasability, one or two or more thermoplastic resins selected from petroleum resins, rosin resins, terpene resins, and styrene resins can be used. The thickness of the release layer is preferably about 0.05 to 2.0 μm from the viewpoint of thermal transfer suitability. Further, the melting point of the release layer is preferably 100 ° C. or higher from the viewpoint of heat resistance during vapor deposition.

The heat-resistant layer for vapor deposition used in the present invention has a function of heat resistance during vapor deposition and retains the vapor-deposited layer, and is a layer mainly composed of a thermoplastic resin (including an elastomer). As the thermoplastic resin, polyester resin, polyamide resin, polyurethane resin, (meth) acrylic resin, ionomer resin and the like can be used. From the viewpoint of heat resistance during vapor deposition, the vapor deposition heat-resistant layer preferably has a softening point of 100 ° C. or higher. The thickness of the vapor-deposited heat-resistant layer is preferably from 0.1 to 1.0 μm from the viewpoint of thermal transferability. If the thickness is less than 0.1 μm, mechanical strength cannot be ensured, and there is a possibility that the deposited layer may be broken during transfer. The thickness is 1.0μ
When m exceeds m, the print tends to lack high definition.

The vapor deposition layer in the present invention is an organic pigment vapor deposition layer. Examples of the organic pigment used in the vapor deposition layer include perylene-based, azo-based, quinacridone-based, phthalocyanine-based, induslone-based, quinophthalone-based, and isoindolinone-based organic pigments. These can be used alone or in combination of two or more. The vapor deposition method is not particularly limited, but a physical vapor deposition method such as a vacuum vapor deposition method is possible. The thickness of the deposited layer should be 5
The range of 0 to 1000 nm is preferable, and especially 50 to
A range of 200 nm is preferred.

The adhesive layer is mainly composed of an adhesive resin. Examples of the adhesive resin include a polyester resin, a polyamide resin, a polyurethane resin, an ethylene-vinyl acetate copolymer, a rosin resin, a terpene resin, and a phenol resin. The softening point of the adhesive layer is preferably from 50 to 120C from the viewpoint of transferability. In addition, a small amount of particles or a lubricant may be added to prevent generation of blocking or background fouling. The thickness of the adhesive layer is suitably 0.05 to 2.0 μm.

[0012]

Hereinafter, the present invention will be described with reference to examples.
The present invention is not limited to this.

EXAMPLE A 2.5 μm thick polyethylene terephthalate film provided with a 0.2 μm thick silicone resin-based stick prevention layer on one side was used as a base material, and the following layer was formed on the side opposite to the stick prevention layer. Were sequentially formed.

Release layer coating liquid Ingredients Parts by weight Polyethylene oxide wax (softening point 105 ° C.) 10 Toluene 90 Total 100

This coating solution was applied on the substrate and dried to form a 0.2 μm-thick release layer.

[0016] Coating solution for vapor-deposited heat-resistant layer Component parts by weight Acrylic resin (softening point 120 ° C) 10 Methyl ethyl ketone 90 Total 100

This coating solution was applied on the release layer and dried to form a 0.3 μm thick vapor-deposited heat-resistant layer.

An organic pigment, phthalocyanine blue, was vapor-deposited on the heat-resistant layer by vacuum vapor deposition to form a vapor-deposited layer having a thickness of 70 nm.

Coating Solution for Adhesive Layer Ingredients Parts by weight Ethylene-vinyl acetate copolymer 9.5 (softening point 65 ° C., vinyl acetate content 19% by weight, melt flow rate 150) Silica (average particle size 1.0 μm) 0. 5 Isopropyl alcohol 90 Total 100

This coating solution was applied on the above-mentioned vapor-deposited layer and dried to form an adhesive layer having a thickness of 0.3 μm, thereby obtaining a thermal transfer recording medium.

Comparative Example 1 In place of the vapor-deposited heat-resistant layer and the organic pigment vapor-deposited layer of the example, a 0.3 μm-thick colored layer formed by applying and drying the following colored layer coating solution on the release layer was used. Except for the above, a thermal transfer recording medium was produced in the same manner as in the example.

Coloring layer coating liquid Ingredients Parts by weight Acrylic resin (softening point 120 ° C.) 5 Phthalocyanine blue 5 Methyl ethyl ketone 90 Total 100

Comparative Example 2 The procedure of Comparative Example 1 was repeated, except that the colored layer of Comparative Example 1 was replaced with a colored layer coating solution described below and dried to form a colored layer having a thickness of 1.0 μm. Thus, a thermal transfer recording medium was manufactured.

Colored layer coating liquid Ingredients Parts by weight Ethylene-vinyl acetate copolymer (softening point 55 ° C.) 5 Phthalocyanine blue 5 Toluene 90 Total 100

The haze and print density of the thermal transfer recording media obtained in Examples and Comparative Examples 1 and 2 were measured. Table 1 shows the results.

<Haze Measurement> Haze is a characteristic value for evaluating transparency, and the total transmittance Ta and the diffuse transmittance Td of the sample were measured with a spectrophotometer, and were determined by the following equation. Haze (%) = [Ta / Td] × 100 The smaller the value, the more transparent.

<Measurement of Printing Density> An image is formed under the following printing conditions, and the reflection density is measured with a reflection density measuring device R manufactured by Macbeth.
It was measured by D-914.

<Print conditions> Thermal transfer printer: MD5000 manufactured by Alps Electric Co., Ltd. Printing paper: High-grade paper (Alps Electric Co., Ltd.)
Print pattern: solid pattern

[0029]

[Table 1]

[0030]

According to the present invention, a thermal transfer recording medium having a thin film, excellent transparency and high reflection density can be obtained.

Claims (1)

[Claims] 1. A thermal transfer recording medium provided with at least a heat-resistant layer for vapor deposition, a vapor-deposited layer, and an adhesive layer on a substrate, wherein the vapor-deposited layer is a colored layer obtained by vapor-depositing an organic pigment. Thermal transfer recording medium.