JPS59224394A - Thermal transfer material - Google Patents

Abstract

PURPOSE:To obtain a thermal transfer material having favorable preservability and capable of faborably printing even on a recording medium having poor surface smoothnees, by a method wherein a thermal transfer layer of a thermal transfer material is provided with a microporous resin structure, and a thermally transferrable ink containing a sublimable dye is incorporated into micropores of the resin structure. CONSTITUTION:A thermoplastic resin structure 4 having a microporous structure is provided on a base 2 consisting of a known film, paper or the like. A homopolymer or copolymer comprising vinyl chloride, vinyl acetate, acrylic acid, methacrylic acid or the like as a monomer is preferably used as the thermoplastic resin. A thermally transferrable ink 6 consisting of an oily or fatty carrier incompatible with the resin of the structure 4 and a sublimable dye is packed into the structure 4. The dye is used in an amount of 20-100 parts per 100 parts of the carrier. The thermal transfer material is transferred onto a recording medium by impressing a thermal pattern by a thermal head in a conventional method for thermal transfer recording, thereby recording is performed.

Description

DETAILED DESCRIPTION OF THE INVENTION Undeveloped IJIJ relates to a thermal transfer material that provides a transferred recorded image with good print quality even on a recording medium with poor surface smoothness.

In recent years, with the rapid development of the information industry, various information processing systems have been developed, and recording methods and devices suitable for each information processing system have also been developed and adopted. One such recording method is the thermal recording method.
The equipment used is lightweight, compact, noiseless, and has excellent operability and maintainability, and has recently been widely used.

However, among the recording papers used in thermal recording methods, ordinary thermal recording paper is a color-forming processed paper containing a color former and a color developer, so it is expensive, and records can be tampered with. The paper has disadvantages in that it has poor storage stability, such as the paper easily developing color due to heat or organic solvents, and the recorded image fading in a relatively short period of time.

Thermal transfer recording method has recently been attracting particular attention as a method that maintains the above-mentioned advantages of the thermal recording method and compensates for the disadvantages associated with the use of thermal recording paper. In this method, a heat-sensitive transfer material is prepared by melt-coating a heat-transferable ink consisting of a colorant in a heat-melting binder on a sheet-like support, and the heat-transferable ink layer of the heat-sensitive transfer material is The ink layer is superimposed on the recording medium so as to be in contact with the recording medium, and heat is supplied from the support side of the thermal transfer material using a thermal head to transfer the melted ink layer onto the recording medium. It forms a transfer ink image. According to this method, it is possible to maintain the above-mentioned advantages of the thermal recording method, use paper as a recording medium, and also eliminate the disadvantages associated with the use of thermal recording paper described in 1-1. .

However, conventional thermal transfer recording methods are not without drawbacks. In the conventional thermal transfer recording method, the transfer recording performance, that is, the print quality, is greatly affected by the smoothness of the surface. In some cases, the print quality deteriorates significantly. However, even when using paper, which is the most typical recording medium, highly smooth paper is rather special, and ordinary paper has various degrees of unevenness due to the entanglement of am. Therefore, in the case of paper with large surface irregularities, the hot-melted ink during printing cannot penetrate into the paper's Fa fibers and adheres only to the convexities on the surface or the vicinity thereof, resulting in sharp edges of the printed image. Otherwise, part of the image may be missing, resulting in a decrease in print quality. Additionally, in order to improve printing quality, it is possible to use a heat-melting binder with a low melting point, but in this case, the heat-transferable ink layer becomes sticky even at relatively low temperatures, resulting in poor storage stability. This causes inconveniences such as deterioration and staining of non-printing areas of the recording medium.

The main object of the present invention is to eliminate the drawbacks of the conventional thermal transfer recording method described above, and to provide high quality recording media not only for recording media with good surface smoothness but also for recording media with poor surface smoothness. An object of the present invention is to provide a heat-sensitive transfer material that can provide accurate printing.

According to the ωF research conducted by the present inventors, in order to achieve the above object, an ink containing a sublimable dye in the micropores of a microporous resin structure is used on the support instead of a normal heat-melting ink. It has been found to be very effective to form a thermal transfer layer containing That is, when the thermal transfer materials obtained in this manner are stacked so that the thermal transfer layer is in contact with a recording medium with poor surface M'rii properties, and heat is supplied to the thermal transfer layer in a pattern, the ink in the thermal transfer layer is recorded. In addition to being transferred to the medium surface, the sublimable dye in the ink sublimates and reaches all four areas of the recording medium's surface, staining the four areas of the recording medium's material, making it ideal for recording media with poor surface smoothness. It is also possible to record images of good print quality without any defects in print. In addition, since the ink is contained in the fine pores of the 11+1 porous resin, the tackiness of the thermal transfer layer at room temperature is effectively suppressed, and even when it comes into contact with the recording medium, it does not stick to the recording medium. The storage stability of the thermal transfer material is improved.

The thermal transfer material of the present invention is based on the above-mentioned knowledge, and more specifically, the thermal transfer material of the present invention is formed by forming a thermal transfer layer on a support,
The thermal transfer layer is characterized by containing a thermal transfer ink consisting of a sublimable dye and an oily carrier incompatible with the thermoplastic resin in the micropores of a microporous resin member made of a thermoplastic resin. That is.

Hereinafter, the present invention will be described in further detail with reference to the drawings as necessary. “%” indicates quantitative ratio in the following descriptions.
"Parts" and "parts" are based on weight unless otherwise specified.

FIG. 1 is a schematic cross-sectional view in the thickness direction of a thermal transfer material in the most basic embodiment of the present invention, and FIG. 2 is a schematic enlarged view of section A in FIG. That is, the thermal transfer material 1 is usually formed by forming a thermal transfer layer 3 on a support 2 in the form of a sheet (used to include a film).

As the support 2, conventionally known films and papers can be used as they are, such as relatively heat-resistant plastic films such as polyester, polycarbonate, triacetyl cellulose, nylon, and polyimide, cellophane, or parchment paper. can be suitably used. The thickness of the support is 1. When considering a thermal head as a heat source for thermal transfer, it is desirable that the diameter be about 2 to 15 microns, but there are no particular restrictions when using a heat source such as a laser beam that can selectively heat the thermal transferable ink layer. do not have. In addition, when using the thermal spatula 1ζ, a heat-resistant protective layer made of silicone resin, fushu resin, polyimide resin, epoxy resin, phenol resin, melamine resin, nitrocellulose, etc. is applied to the surface of the support that comes into contact with the thermal head. By providing this, it is possible to improve the heat resistance of the support, or it is also possible to use a support material that could not be used conventionally.

The thermal transfer layer 3 is made of a fine porous resin fiber 3 as shown in FIG. A thermal transfer ink 6 made of a soluble oil-based carrier is filled.

Although the method for manufacturing the thermal transfer layer 3 having the structure described above is not particularly limited, the following method is generally used. That is, an oleaginous carrier and a sublimable dye are mixed with a suitable organic solvent using a dispersing device such as an attritor.1. Mix and disperse X and C to obtain an ink dispersion (or a solution). 5] Step 11: A solution of a thermoplastic resin dissolved in an organic solvent is obtained, mixed with the ink dispersion liquid, and uniformly dispersed using a mixer such as a Pall mill.

Next 1. By applying the dispersion obtained in step 1 on a support and drying it, the thermal transfer material 1 of the present invention having the thermal transfer layer 3 having the above-mentioned fine structure can be obtained. In the dispersion,
A wetting agent may be added to improve the dispersion of the above-mentioned oily carrier and sublimable dye. Yes.Heat that forms the microporous resin structure 5■
The plastic resin may be a monomer selected from vinyl chloride, vinyl acetate, vinylidene chloride, acrylic acid, methacrylic acid, acrylic ester, and methacrylic ester depending on the relationship with the oil-based carrier as described below. It is preferable to use a single polymer or a copolymer.

As another method, a thermoplastic resin that is incompatible with the thermoplastic resin forming the porous structure and does not dissolve the resin may be mixed with heat D (a soluble substance is kneaded with the plastic resin,
It is also possible to form a resin layer by applying the material to 1-2, and then dissolving the substance in a solvent such as 111 to form a porous resin structure, and then filling the porous structure with thermal transferable ink. A thermal transfer layer having the structure described above is obtained.

In addition, as an oil carrier, if it is incompatible with the heat 11 plastic resin and non-volatile as described in ``-'', it can be used as an oil carrier, semi-solid, or meltable solid glue. is also used. Liquid carriers include, for example, animal and vegetable oils such as cottonseed oil, rapeseed oil, and whale oil; or acupuncture oils such as motor oil, spindle oil, and dynamo oil; and semisolid carriers include, for example, lanolin, petrolatum, lard, and the like.

Further, as a solid carrier, a heat-melting paint that constitutes a heat-melting ink in a normal heat-sensitive transfer material can be used, such as carnauba wax, paraffin wax, Sasol wax, microblisterine wax, castor wax, etc. waxes; higher fatty acids such as stearic acid, palmitic acid, lauric acid, aluminum stearate, lead stearate, barium stearate, zinc stearate, zinc palmitate, methylhydroxystearate, glycerol monohydroxystearate, or their metals. Derivatives such as salts and esters;
Polyethylene, polypropylene, polyisobutylene, polyethylene wax, polyethylene oxide, polytetrafluoroethylene, ethylene-acrylic acid copolymer, ethylene-
Thermoplastic resins made of olefins alone or copolymers, such as ethyl acrylate copolymer, ethylene-vinyl acetate copolymer, or derivatives thereof, are used. These oil-based carriers are used alone or in a mixture of two or more in a proportion of 50 to 200 parts per 100 parts of the thermoplastic resin constituting the thermal transfer layer.

Furthermore, as sublimable dyes, dyes that sublimate or evaporate in the temperature range of 70 to 200°C and have greater affinity or compatibility with oil-based carriers than thermoplastic resins are preferably used, such as disperse dyes, base dyes, etc. sex dye,
Can be arbitrarily selected from oil-soluble dyes, etc. Examples are 1.
4-diamino-2,3 dichloro-anthraquinone, l-
Amino-2-phenol-4-hydroxy-anthraquinone, 3-hydroxyquinophthalone, l-amino-2-cyano-4-aryanthraquinone, 1,4
-Sibide Draw 5-amino-8-isopropylamino-
Examples include anthraquinone. These sublimable dyes are
Oil-based carrier 100 alone or in combination of two or more
It is used in a ratio of 20 to 100 parts.

In addition to the above-mentioned sublimable dye, the thermal transfer ink 6 may contain dyes, pigments, carbon black, etc. contained in ordinary heat-melting inks, if necessary, for the purpose of adjusting the color tone and density of the transferred recorded image. Colorants may also be added. Further, the thickness of the thermal transfer layer 3 is preferably in the range of 10 to 30 JL.

The thermal transfer recording method using the thermal transfer material of the present invention thus obtained is not particularly different from a conventional method. The heat-sensitive transfer material and the recording medium may be separated from each other after the heat-sensitive transfer material and the recording medium are laminated and heat is supplied in a pattern according to the desired recording pattern, preferably from the support side of the heat-sensitive transfer material using a thermal head or a laser beam. A recorded image corresponding to the heat supply pattern is obtained on the separated recording medium.

As described above in detail, according to the present invention, the thermal transfer layer is made of a microporous resin, and by containing a thermal transfer ink containing a sublimable dye in the micropores, the thermal transfer layer has poor surface smoothness. A heat-sensitive transfer material that provides a recorded image of good print quality without any defects on the recording medium and has good storage stability with suppressed surface tackiness is provided. In addition, by adjusting the sublimation temperature of the sublimable dye in the thermal transfer ink, or by adding an ordinary coloring agent to the thermal transfer ink, this thermal transfer material has the ability to be used repeatedly, which is not possible with ordinary thermal transfer materials. You can also give

Hereinafter, the present invention will be explained in more detail with reference to Examples.

Example 1) Ruene 70g Rapeseed oil 25g Hydroxy-quinophthalone 10g (+11 flower dye) Lecithin 5g-1 The above ingredients were mixed with a stainless steel pole using an attritor for 30 minutes to obtain an ink dispersion. Furthermore, 11
Add a long solution of vinyl monide/vinyl acetate conjugate 20% by weight in methyl ethyl ketone and stir for 10 minutes +1″-,
A smooth thermal transfer ink was obtained.

This thermal transfer ink was applied to a 4IL thick polyester film using a No. 6 wire bar and dried to a thickness of 1511mm. A thermal transfer material having a thermal transfer layer made of a porous resin composition containing ink in the micropores was obtained. Canoward 55 was applied using a wood thermal transfer material under the conditions of applied pressure 1, 6 kg/c rrl, and heat pulse 1115 msec.
When printed with a thermal printer, good prints in several colors were obtained regardless of the smoothness of the paper.

Comparative Example 1゜ Using a transfer material obtained by replacing the hydroxyquinophthalone in Example 1 with non-sublimable Zapon Fast Yellow, the applied pressure was 1.6 Kg/cnf and the heat pulse was 11''5 m.
When printing was performed under conditions 5-e-a, only unclear prints were obtained.

Example 2 The same results as in Example 1 were obtained in a transfer material obtained by replacing the rapeseed oil in Example 1 with lanolin.

Example 3 The same results as in Example 1 were obtained in a transfer material obtained by using a methyl methacrylate polymer in place of the resin of Example 1, the vinyl chloride/vinyl acetate copolymer.

[Brief explanation of the drawing]

FIG. 1 is a schematic cross-sectional view in the thickness direction of a basic embodiment of the thermal transfer material of the present invention, and FIG. 2 is a section A in FIG. 1. l-fist/thermal transfer material 2...support 3...thermal transfer layer 4...microporous resin member 5...micropores 6...thermal transfer ink

Claims (1)

[Scope of Claims] 1. A thermal transfer layer is formed on a support, and the thermal transfer layer contains a sublimable dye and the thermoplastic resin in the micropores of a microporous resin structure made of a thermoplastic resin. A thermal transfer material characterized by containing a thermal transfer ink consisting of a conventional carrier [incompatible oil]. 2. The thermoplastic resin is vinyl chloride, vinyl acetate,
The heat-sensitive transfer material according to claim 1, comprising a monomer or a copolymer of monomers selected from vinylidene chloride, acrylic acid, methacrylic acid, acrylic esters, and methacrylic esters.