JPS58201693A - Heat sensitive transfer type recording material - Google Patents

Abstract

PURPOSE:To obtain a heat sensitive transfer type recording material, which is prepared by including a vinyltoluene copolymer resin having a specific melting point and a coloring agent in a transfer layer, has excellent abrasion resistance, and does not have the possibility of being altered. CONSTITUTION:(A) A vinyltoluene copolymer resin (it is desirable to have a copolymer of vinyltoluene and butadiene or the like at a mol ratio of 1:0.1-1, which has molecular weight of 1,000-20,000 and a melting point or softening point of 60-150 deg.C) and (B) a coloring agent (e.g. azo dye, carbon black, or the like) are used desirably at a rate of 0.5-3 parts of the component A with respect to 1 (weight) part of the component B. The material is layered on a sheet base material to a desirable thickness of 1-10mum by a solution method or a fusing method. Thus an intended recording material is obtained. Furthermore, a heat fusible material (e.g. beeswax, paraffin wax, or the like) having a melting point of 60-120 deg.C is added in the transfer layer as required.

Description

Detailed Description of the Invention The present invention uses a thermal recording head to heat a transfer layer provided on the bottom surface of a transfer sheet and transfer it to a recording medium such as paper, plastic, or metal foil. In the heat-sensitive recording material used in the heat-sensitive transfer recording method, the transfer layer contains a vinyl toluene copolymer resin having a melting point or softening point in the range of 60°C to 150°C and a coloring agent such as a disperse dye or a colored pigment. The present invention relates to a heat-sensitive transfer type recording material.

Recently, various recording sheets have been researched, developed, and put into practical use in the field of information recording in response to social demands such as diversification and increase in information, resource conservation, and pollution-free environment. Among these, thermosensitive recording materials (2) have a relatively simple and compact device, as a colored image is recorded simply by heating, and no complicated development process is required, and the resulting recording material is easy to handle. (3) Paper is often used as a support, and in this case, not only is the support cost low, but the resulting recording material has a feel similar to that of plain paper. Because of the advantages, computer output,
It is widely used in the fields of printers such as calculators, recorders for medical measurement, facsimiles, automatic ticket vending machines, thermal copying, etc.

As the heat-sensitive recording materials commonly used here, dye coloring type or metal compound type are known. Among these, many utilize the reaction between leuco dyes and bisphenols due to their advantages such as less background capri and clearer colored images. However, recently, the reliability of images has become a problem, especially the decolorization and tamperability of images caused by organic solvents and plasticizers. In addition, a thermal transfer recording method for obtaining a transferred image onto plain paper using a transfer sheet of thermal transfer recording material has also been proposed and put into practical use. This thermal transfer recording material is satisfactory in that there is no background fogging or decoloring of the image, but due to contact between the transfer layer of the transfer sheet and the recording material, there are problems such as background staining, transfer stability, resolution of the transferred image, etc. However, the quality is still not satisfactory.

Therefore, in order to solve the above-mentioned drawbacks, the inventor of the present invention has conducted intensive research and found that by containing a vinyltoluene copolymer resin and a colorant in the transfer layer of a transfer sheet, it has excellent abrasion resistance and It was discovered that a heat-sensitive transfer type recording material without fear of falsification can be obtained, and the present invention was completed.

That is, according to the present invention, in a heat-sensitive recording material used in a heat-sensitive transfer recording method in which recording is obtained by transferring a transfer layer of a transfer sheet to a recording material using a thermal head, the transfer layer has a melting point or a softening point. A heat-sensitive transfer recording material is provided, which contains a vinyltoluene copolymer resin having a temperature of 60°C to 150°C and a colorant.

The vinyltoluene copolymer resin used in the present invention is obtained by a copolymerization reaction of vinyltoluene and other copolymerizable monomers. Examples of the comonomer include polymerizable compounds having double bonds such as butadiene, inbutylene, diisobutylene, styrene, acrylate, and methacrylate. The proportion of the comonomer used is preferably in the range of 0.1 to 1 mole per mole of vinyltoluene, and the molecular weight of the resulting vinyltoluene copolymer resin is 1.00 to 2.
A range of 00,000 is preferred.

The vinyltoluene copolymer resin used in the present invention preferably has a melting point or softening point in the range of 60°C to 150°C. If the melting point or softening point is lower than 60° C., the transferred image may be rubbed by hand, resulting in image fading and poor abrasion resistance. On the other hand, if the temperature exceeds 150°C, there is a drawback that transferability deteriorates.

The coloring agent used in the present invention is selected from disperse dyes such as azo dyes and anthraquino/dyes, and coloring pigments such as organic or inorganic pigments and carbon black, taking hue, density, etc. into consideration. In addition, 1. The vinyl toluene copolymer resin used in the present invention is used in a proportion of 0.1 to 5 parts by weight, preferably 0.5 to 3 parts by weight, per 1 part by weight of the above-mentioned disperse dye or coloring pigment. used in

In the present invention, either a solution method or a melt method can be adopted as a method for layering a transfer layer made of a vinyltoluene copolymer resin, a colorant, etc. on a sheet base material. In order to obtain even better transferability or resolution, it is desirable to make the transfer layer as thin as possible, particularly preferably in the range of 1 to 10μ. If it is less than 1 μm, a recording density cannot be obtained, and if it exceeds 10 μm, heat conduction will be insufficient and complete transfer will not occur, making it impossible to obtain a uniformly transferred image.

In the present invention, if necessary, thermofusible substances with a melting point in the range of 60 to 120°C, such as animal waxes such as beeswax and shellac wax, vegetable waxes such as carnauba wax, and mineral waxes such as montan wax, are used. Waxes, paraffin wax, petroleum waxes such as microcrystalline wax, polyhydric alcohol esters of higher fatty acids, higher amides,
Higher amines, condensates of fatty acids and amines, condensates of aromatics and amines, synthetic waxes such as synthetic paraffins, chlorinated paraffins, etc. can be used in combination.

To obtain a record using the thermal transfer type recording material of the present invention, the surface of the transfer layer is applied to ordinary paper, plastic film, metal foil, etc., and the recording material is heated from the back side with a thermal head such as a thermal recording head. , just pressurize. The recorded surface obtained in this way is this! It also has wear resistance, and even if the recording surface is intentionally scraped, there is little risk of tampering because the colorant has penetrated into the inside. Heat can also be applied to this surface using a heater or flash lamp to improve wear resistance and permeability.

In the present invention, the support for forming the transfer layer is preferably a plastic film (for example, polyester, polycarbonate, cellulose acetate, etc.) with a thickness of 5 to 30 microns, cellophane, condenser paper, glassine paper, and the like.

Next, the present invention will be explained in more detail with reference to examples.0 Example 1 Vinyl toluene copolymer resin 40 parts by weight (Priolide VT manufactured by Gutdeyer) Carbon black 45 parts by weight Montan wax (0F-WAX manufactured by Hoechst) 10 Parts by weight Stearylamine 5 parts by weight The above composition was melted by heating, and a uniform dispersion was prepared using condenser paper (
A transfer sheet (thermal transfer type recording material) was obtained by coating the film to a thickness of 5 μm on a 12 μm thick film. The transfer layer surface of this transfer sheet was superimposed on plain paper (55 g/m2) and printed using a Ricoh facsimile machine (FLIFAX-3300) to obtain a black record. This transferred image has good abrasion resistance,
There was no blurring in the image. Furthermore, even if you rub it with a sand-filled eraser, it will penetrate into the paper, so there is little risk of tampering.

Example 2 Vinyl toluene copolymer resin 20 parts by weight (Picotex-1oo, manufactured by Knit Kasei) Disperse dye: Dianix black 10 parts by weight Carbon black 10 parts by weight Paraffin wax 5 parts by weight Cyclohexane 55 parts by weight The above composition was uniformly dispersed. A black image was obtained using the dispersion liquid in the same manner as in Example 1. The abrasion resistance of the transferred image was good, and there was no blurring of the image.

Comparative Example 1.2 Transfer sheets of Comparative Examples 1 and 2 were obtained by removing the vinyltoluene copolymer resin from Examples 1 and 2, and recorded images were obtained by the same operation as in Example 1. This transferred image peeled off just by rubbing it by hand, and its abrasion resistance was not practical.

Comparative Example 3 A comparative transfer sheet was obtained in exactly the same manner as in Example 1 except that polystyrene resin was used instead of the vinyltoluene copolymer. A transferred image was obtained using this product in the same manner as in Example 1. This transferred image had poor resolution and was uneven.

Patent applicant Ricoh Co., Ltd. Agent Patent Attorney Toshiaki Ikeura

Claims (1)

[Claims] (1) In a thermal recording material used in a thermal transfer recording method in which recording is obtained by transferring the transfer layer of a transfer sheet to a recording material using a thermal head, the transfer layer has a melting point or softening point of 60°C to 150°C. 1. A heat-sensitive transfer recording material characterized by containing a vinyltoluene copolymer resin and a colorant having a temperature range of .degree.