JPH02150386A - Novel thermal transfer recording medium - Google Patents

Abstract

PURPOSE:To enable low energy printing to be performed by a method wherein a thermal fusible color material layer is provided directly on a base material, and the thermal fusible color material layer contains one type or two types or over thereof selected from novel styrene-ethylene-butylene-styrene block copolymer resin and a specified compound group. CONSTITUTION:One or not less than two thermal fusing color material layers are established directly on a base material. The thermal fusible color material layer is composed of one or not less than two types of thermal fusing color material layers selected from novel styrene-ethylene-butylene-styrene block copolymer having polystyrene terminal block and an intermediate block having crystalline ethylene-butylene rubber block, and selected from animal wax, plant wax, mineral wax, petroleum wax, synthetic resin hydrocarbon wax, and modified wax. It is preferable to use at most within 30wt% novel styrene-ethylene- butylene-styrene block copolymer resin, of which weight average molecular weight is within a range of 5,000 to 200,000, of which polystyrene content is a range of 5 to 45wt%, and of which intermediate block material has crystalline ethylene-butylene block, in a thermal transfer recording medium.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to a novel thermal transfer recording medium that can be used multiple times. Specifically, it is a thermal transfer recording medium that can be printed with low energy, has good printability and print retention durability even on uneven paper such as plain paper, and can provide clear and high quality print quality. Regarding.

[Prior Art] Examples of thermal transfer recording media intended for multiple use that have been disclosed as prior art include, for example, JP-A No. 5
5-105579 describes a technique of forming a fine porous layer and impregnating the layer with ink, and JP-A-57-160691 describes a technique using organic or inorganic fine powder. A technique for forming a network structure and impregnating it with ink was described, and Japanese Patent Application Laid-Open No. 57-18
No. 5192 describes a technique for impregnating porous paper with ink, and JP-A-54-68253 describes a technique in which a resin and solid components immiscible therewith are dissolved and dispersed in a volatile solvent. A technique is described in which a fine porous layer of a resin component is formed on a support after evaporation of the solvent.

Further, JP-A-61-162395 describes a technology for a thermal transfer recording medium made of polyethylene glycol diester or wax that is solid at room temperature.

[Problems to be Solved by the Invention] One of the above-mentioned conventional technologies is that they are all designed to allow ink to seep out little by little from a porous solid base material. Because the solid base material to be formed does not melt or mix with heat-melting substances when energy is applied, and the solid base material is substantially transferred, the density of the dye transfer image is reduced as a result. It has the problem of not being able to provide clear print quality many times, and in order to obtain clear print with high density, high energy is required, resulting in a significant drop in resolution. There is.

This kind of development can be seen as simply utilizing the technique disclosed in Japanese Patent Application Laid-Open No. 35-13426 for a thermal transfer ribbon, and due to the problem of the transfer principle, the printing sensitivity is extremely poor and inconvenient.

On the other hand, as an attempt to solve the first problem, there have been disclosed, for example, JP-A-57-36698 and JP-A-59-9699.
Publication No. 2 discloses a method of interposing an adhesive layer as a technique for adjusting the transfer amount of the heat-melting coloring material layer, but according to this method, it is possible to Compared to paper, there are problems such as low dye transfer image density and severe loss of density after multiple printings.

Furthermore, as an attempt to solve the first and second problems, for example, Japanese Patent Application Laid-open No. 162395/1983 discloses a technique for changing the temperature of the heat-fusible coloring material layer by using an adhesive layer.
A technique for using solid polyethylene glycol diester or wax as a thermal transfer recording medium is disclosed. According to this method, it is possible to transfer a large number of sheets to transfer paper with low surface smoothness using low energy. It is stated that printing with high dye transfer image density is possible with multiple printings, but considering the printing reliability below, this technology is suitable for use with thermal transfer recording media other than those made mainly of carnauba wax. do not have.

According to the thermal transfer recording medium of this method, the dye transfer image lacks adhesion to the transfer paper with low surface smoothness, is hard, and is brittle, so it is difficult to handle the dye after printing. When it comes to problems where the transferred image cracks and falls off, resulting in a decrease in resolution, carnauba wax works reasonably well, but in other cases, including other known technologies, overall print durability and dye resolution are significantly reduced. has shortcomings and results;
A thermal transfer recording medium with high printing durability after printing is desired.

In other words, in recent years, thermal transfer recording media based on well-known carnauba wax have been widely used. , high printing performance (high quality) replaced by carnauba wax due to price etc.
There is a strong desire for a new thermal transfer recording medium that can solve the above-mentioned problems of reliability of dye transfer images.

The present invention is capable of low-energy printing, has little density loss with the number of uses, and can produce high-density dye transfer images many times, and can also be applied to paper with low surface smoothness. An object of the present invention is to provide a new thermal transfer recording medium which can be printed clearly and with high density and has extremely good adhesion durability of a single-dye transfer image.

[Means for Solving the Problems] The inventors of the present invention have developed the following in a heat-sensitive transferable recording medium having a heat-melting coloring material layer directly on a support.
the hot-melt colorant layer has polystyrene end blocks;
A new styrene-ethylene-butylene-styrene block copolymer resin having a crystalline ethylene-butylene rubber block in the middle block, and the following compound group (hereinafter referred to as wax compound group) [Wax compound group] Animal-based wax Plant-based wax mineral The present invention has been based on the discovery that the above technical problem can be solved by containing one or more heat-melting substances selected from petroleum-based waxes, synthetic hydrocarbon-based waxes, and modified waxes. reached.

The present invention will be further explained in detail below.

In the heat-sensitive transfer recording medium of the present invention, a direct layer or a 2N or higher heat-melting coloring material layer is provided on a support.

In addition, when two or more heat-melting coloring material layers are formed, the upper layer may be provided with a low softening point composition or a low viscosity composition between the layers.

In the novel thermal transfer recording medium of the present invention, the intermediate block preferably has a polystyrene content in the range of 5 to 45%, and the novel styrene-ethylene-butylene-butylene block is composed of crystalline ethylene-butylene fluorocarbon. Use of a styrene block copolymer resin, more preferably a novel styrene edge resin in which the intermediate block is composed of a crystalline ethylene-butylene block, and the intermediate block contains a high proportion of crystalline polyethylene of at least 60% by weight. A lene-butylene-styrene block copolymer resin is used.

More preferably, the weight average molecular weight is in the range of 5,000 to 200,000, the polystyrene content is in the range of 5 to 45%, and the intermediate block has a crystalline ethylene-butylene block. An ethylene-butylene-styrene block copolymer resin is used.

Most preferably, a novel styrene-ethylene whose weight average half amount is in the range of 5,000 to 200,000, the polystyrene content is in the range of 5 to 45% by weight, and the intermediate block has a crystalline ethylene-phthylene proton. A novel thermal transfer recording medium in which a butylene-styrene block copolymer resin is used in an amount of at most 30% by weight is preferred.

Further, in the novel thermal transfer recording medium of the present invention, the wax compound group includes a heat-melting substance selected from animal waxes, vegetable waxes, mineral waxes51, petroleum waxes, synthetic hydrocarbon waxes, and modified waxes. It is preferable to use one or more of these as essential components in a thermal transfer recording medium in an amount of at least 70% by weight.
Furthermore, in the present invention, an ethylene-vinyl acetate copolymer resin having a vinyl acetate content of 28% by weight or less, a polyethylene glycol diester having a weight average molecular weight in the range of 400 to 30,000, and ethylene-ethyl having an ethyl acrylate content of 35% by weight or less Acrylate copolymer resin, aromatic tackifier resin, alicyclic tackifier resin, rosin ester tackifier resin, crystalline polyester resin, styrene-ethylene-butylene-styrene block consisting of an amorphous intermediate block. A thermomeltable resin material selected from polymeric resins, ethylene-butadiene-styrene block copolymer resins, and styrene-isobrene-styrene block copolymer resins (
It is highly preferable for new thermal transfer recording media to use at most 10% by weight or less of one or more types of resin materials (hereinafter referred to as resin substances) in combination in novel thermal transfer recording media.

Furthermore, in the novel thermal transfer recording medium of the present invention, the elongation rate of the molded product of the thermal transfer recording medium alone should be at least 30% or more, and the melt viscosity of the thermal transfer recording medium alone should be 5% at 110°C. ~2000 cps, and furthermore, the softening point temperature of the heat-sensitive recording medium alone by the ring and ball method is
It has been found that it is particularly preferable to maintain the temperature within the range of 60°C to 130'C.

The novel styrene ethylene-butylene-styrene block copolymer resin having a polystyrene end block and a crystalline ethylene-butylene rubber block in the intermediate block used in the present invention is a conventionally known non-crystalline intermediate block copolymer resin. The styrene-ethylene-butylene-styrene block copolymer resin having a block body is essentially a heterogeneous one, that is, the intermediate ethylene-butylene rubber block chain portion of the resin exhibits crystallinity in a normal state. A new styrene-ethylene-butylene-styrene Pronk copolymer resin resin that has been controlled and adjusted to have a sufficiently high ratio of ethylene content and has extremely improved compatibility with wax compounds. Either a styrene ethylene-butylene-styrene block copolymer resin having a crystalline intermediate block and a crystalline low-molecular or medium-molecular polyethylene, or a crystalline ethylene-butene copolymer resin having a high proportion of polyethylene. As a result, the resin is adjusted to have a high proportion of ethylene content that is sufficient to exhibit crystallinity in the normal state, and the compatibility with the wax compound group is extremely improved. This refers to a new styrene-ethylene-butylene-styrene block copolymer resin containing a crystalline polyethylene-based or crystalline polyethylene-butene-based chain polymer.

The novel styrene-ethylene-butylene-styrene block copolymer resin having the polystyrene terminal block described in the present invention and having a crystalline ethylene-butylene rubber block in the middle block was presented, for example, at the 1988 Exhibition in Atlanta, USA. At the TAPPI International Conference, Shell
It is published by Chemical Company and is easily available on the market.

i.e. with polystyrene end blocks, a high proportion of 1,4-butadiene in the middle block, and a low proportion of 1,2-butadiene.
- A method in which a styrene-butadiene-styrene block copolymer with a controlled distribution of butadiene is produced and then hydrogenated so that the intermediate block exhibits crystallinity, and a method in which a high proportion of ethylene and a low A method of polymerizing the respective proportions of 1-butene and coupling with a known coupling compound to obtain a resin having a moderately crystalline intermediate rubber block, and furthermore, a resin having an amorphous intermediate rubber block. Styrene-ethylene-butylene-styrene block copolymer resin with crystalline low-molecular or medium-molecular polyethylene,
or a crystalline ethylene-butene copolymer resin with a high proportion of polyethylene, respectively, obtained by graft polymerization, resulting in a sufficiently high proportion of ethylene content to exhibit crystallinity under normal conditions. Similarly, there is a method of producing a resin obtained by modifying it so that a chain polymer of crystalline polyethylene or crystalline polyethylene-butene is disposed thereon. , as a typical synthesis example of a new styrene-ethylene-butylene-styrene block copolymer resin having a crystalline ethylene-butylene rubber block in the intermediate block.

The crystallinity described in the present invention means that the intermediate rubber block exhibits behavior similar to the crystallinity of low-density polyethylene, especially in the range from room temperature to about 120°C.
Preferably in the range of 20°C to 70°C, it means a property observed as a melting heat absorption peak in a differential scanning calorimeter.

Another aspect of the present invention can be achieved by using a new styrene-ethylene-butylene-styrene block copolymer resin having the polystyrene end blocks described above and having a crystalline ethylene-butylene rubber block in the intermediate block. As a result, the miscibility with the Wanks compound group compound, which is a component, is significantly improved, and as a result, the hardness of thermal transfer recording media in the prior art, which is the technical problem typified by solid wax compounds, is improved. This greatly improves the brittle properties (the effect of improving toughness without increasing rigidity), and also improves pigment dispersion stability when ink pigments such as carbon blank are contained in the heat-melting coloring material layer. It has excellent thermal stability, hue stability, and weather stability, as well as adequate adhesion to various supports such as coloring material layers or plastic films, making it possible to perform stable, high-density transfers multiple times. I can do it. In addition, even in the case of transfer paper such as plain paper with low surface smoothness, it exhibits the effects of high density and high print quality, that is, excellent print adhesion and durability, sharpening print resolution and dye transfer images. The mechanical adhesion durability retention rate is greatly improved.

The wax compound group substances used in the present invention include waxes that are solid at room temperature, preferably having a melting point of 40°C to 80°C.
Waxes in the range 'C' are preferred, and specifically the waxes listed below are typical.

That is, examples of animal waxes used in the present invention include spermaceti wax, wool wax, insect wax, selan wax, beeswax, etc., and examples of vegetable waxes include carnauba wax, tree wax, and carnauba wax. Examples of mineral waxes include monk wax, osichelite, ceresin, etc.; examples of petroleum waxes include paraffin wax, microcrystalline wax, ester wax, petrolatum, and polyethylene gel. Examples of the synthetic hydrocarbon waxes include Finscher-Robutsch wax, polyethylene wax, low molecular weight polypropylene wax, low molecular weight polyethylene waxes and derivatives thereof, and modified Examples of the wax include oxidized wax, monk wax derivatives, paraffin or microcrystalline wax derivatives, and 1
It is also possible to use a species or a combination of two or more species.

In the present invention, hydrogenated waxes such as castor wax and opal wax may be used in combination with Sonx, which is not susceptible to the aforementioned wax compounds.

In addition, in the present invention, the following resin materials such as ethylene-vinyl acetate copolymer resin with a vinyl acetate content of 28% by weight or less, polyethylene glycol diester with a weight average molecular weight in the range of 400 to 30,000, and ethyl acrylate of 35% by weight or less are used.
Ethylene-ethyl acrylate copolymer resin, (hydrogenated) <74) A IIRl (hydrogenated) terpene phenol resin, (hydrogenated) C9 petroleum resin, (hydrogenated)
C5-C9 copolymerized petroleum resin, low molecular weight polystyrene resin,
Aromatic tackifying resins such as styrene-modified petroleum resins, low-molecular α-methylstyrene resins, alicyclic tackifying resins such as (hydrogenated) dicyclopentadiene petroleum resins, and rosin esters. or alicyclic tackifier resin represented by derivatives thereof, crystalline polyester resin, styrene-ethylene-butylene-styrene blank copolymer resin consisting of amorphous intermediate rubber block, styrene-phtadiene-styrene block. The use of one or more selected from copolymer resins, styrene-isoprene-styrene block copolymer resins, polyethylene, polypropylene, etc. in a new thermal transfer recording medium in an amount of at most 10% by weight, Appropriate adhesive properties, appropriate viscosity modification,
The effects of softening temperature = 11, high resolution in low energy printing, and improvement in the strength of printed transfer images are exhibited, and they may be used in combination for such purposes.

In the present invention, a novel styrene resin having the aforementioned polystyrene terminal block in the heat-melting coloring material layer and a crystalline ethylene-butylene rubber block in the intermediate rubber block is used.
The means for incorporating the ethylene-butylene-styrene block copolymer resin and the above-mentioned wax compounds is not particularly limited, and generally they can be obtained by dissolving and mixing them.

In cases where some of the wax compounds show immiscibility,
For example, it may be used by stirring vigorously and uniformly dividing the mixture into 11 portions. Also) after forming a compatible state using 8 agents,
It is also possible to use an IBt solvent to form a finely dispersed state.

In the present invention, there is no particular limitation on the method of forming the heat-melting coloring material layer in the form of an ink. A method in which a styrene-ethylene-butylene-styrene block copolymer resin and the above wax compound group are co-dispersed with a colorant (dye or pigment), optionally containing a resin substance, or one of the components of the present invention. It is also possible to mix and disperse the colorant and the coloring agent separately.

That is, in the present invention, the dispersion of the colorant is carried out before the dispersion of the novel styrene-ethylene-butylene-styrene block co+Li composite resin having the polystyrene end blocks and a crystalline ethylene-butylene rubber block in the intermediate block. or later.

The colorant used in the 14-layer heat-melting color scheme of the present invention may be appropriately selected from various pigments, and particularly preferably direct dyes, acid dyes, basic dyes, disperse dyes, and oil-soluble dyes. (including metal oil-soluble dyes), and indoaniline dyes, azomethine dyes, and the like can also be preferably used. Further, the pigment used in the color material layer of the present invention may be any pigment that can basically be transferred (transferred) together with a heat-fusible substance, and thus organic or inorganic pigments may be used in addition to the above.

Specific examples of the colorant used in the heat-melting color material layer of the present invention include the following. That is, examples of yellow pigments include PS Yellow GO (Mitsui Toatsu Chemical Co., Ltd.), PS Yellow SK (Mitsui Toatsu Chemical Co., Ltd.), Kayalon Polyester Lie 1 to Yellow 5G-3 (Nippon Kayaku Co., Ltd.), and Oil Yellow. S-7 (white clay) Eisen Subiron Yellow GRH Special (Hodogaya), Sumiplast Yellow FG (resident)
, Eisen Subiron Yellow GRI+ (Hodogaya), etc.
Examples of red pigments include PS Red G (Mitsui Toatsu Chemical Co., Ltd.), MS Red VP (Mitsui Toatsu Chemical Co., Ltd.), Diaceritone Fast Red R (Mitsubishi Kasei), Sumiplus Trend FB (Sumiplus), and Sumi Plas Red HFG (Resident), Kayalon Polyester Pink RCL-E (Kuchihon Kayaku), Eisenspiron Resodo CHR Special (Hodogaya), etc. As blue pigments, for example, Miketon Polyester Blue FBL Conch (Mitsui Toatsu) chemical products), PE
T Blue #2,000 (Mitsui Toatsu Chemical Co., Ltd. product), PS Blue BN (Mitsui Toatsu Chemical Co., Ltd. product), Diaceritone Fast Brilliant Blue (Mitsubishi Kasei), Dianic Sprue EB-E (Mitsubishi Kasei), Kaya Rhomboliester Fill B-3F Conc (Nippon Kayaku), Sumiplast Blue 3R (Resident), Sumiplast Blue G (Resident), etc.
In addition, as a yellow colored pigment, for example, Hansa Yellow 3
Examples of red coloring pigments include Brilliant Carmine FB-Pure (mountain pigment), Brilliant Carmine 6B (mountain pigment), Alizarin Lake, etc.; examples of blue coloring pigments include, for example, Cerulean Blue, Sumikablin Tocyanin-j-Rue GN-
Typical examples of black colored pigments include carbon blank, oil blank, etc., and carbon black is the most preferred coloring agent in the present invention.

Although the composition ratio of the heat-melting coloring material layer is not limited,
Based on 100 parts by weight of the solid content of the heat-melting coloring material layer, the heat-melting substance is 5 to 80 parts by weight, preferably 10 to 60 parts by weight, and the coloring material is 5 to 50 parts, preferably 10 to 40 parts. It is preferable to use within this range.

In addition to the above components, various additives may be added to the heat-melting coloring material layer of the present invention, such as castor oil, linseed oil,
Vegetable oils such as olive oil, animal oils and mineral oils such as whale oil, synthetic oils such as liquid polybutene, liquid hydrogenated polyisoprene, paraffin oil and naphthenic oil, lubricating oils such as polyalkylene glycol, fluorine oil and silicone oil, graphite and graphite. , conductive derivatives such as fine metal powders, thermally decomposable blowing agents such as inorganic compounds such as bicarbonates, carbonates, and nitrites, or organic compounds such as sulfonyl hydrazide, thermally expandable microparticles, polymerization inhibitors, and anti-aging agents. Various additives such as UV stabilizers (Kinai stabilizers), UV absorbers (acoustic light absorbers), dispersion stabilizers, viscosity modifiers (including titanium-containing property improvers), surfactants, and high boiling point solvents. It is preferable to use it appropriately depending on the purpose.

In the heat-sensitive transfer recording medium of the present invention, a suitable technique for applying the heat-fusible coloring material layer onto the support may be any known technique, such as photomelt coating or applying the composition. There are coating techniques that use a coating liquid dissolved in a solvent to form a Zurgento coating, and a method that coats emulsilane by dispersing it in water. As a method, known techniques such as a reverse roll coater method, an extrusion coater method, a gravure coater method, a wire/wire bar coating method, etc. can be employed.

Further, the 1[gamma] thickness of the heat-melting coloring material layer-forming coating film of the present invention is not limited, and in terms of -p2, it is preferably 20 microns or less, preferably 10 microns or less, and more preferably 5 microns or less.

In the present invention, one or more heat-fusible coloring material layers may be directly laminated on the support; for example, one heat-melting coloring material layer may be formed using the coating technique described above. In this case, for example, the novel thermal transfer recording medium of the present invention having two different properties may be coated once using two hot melters that are designed not to completely mix each other, and an extrusion composite nozzle. At the same time, the novel thermal transfer recording medium of the present invention may be obtained by a method of coating so that the appearance is one layer, but the material is actually two layers, or when two or more layers are coated, the upper layer is substantially the new thermal transfer recording medium of the present invention. The novel heat-sensitive transfer recording medium of the present invention, which preferably has a relatively high viscosity, can be obtained by making the actual softening point a little lower or by making the melt viscosity a little lower than that of the novel thermal transfer recording medium of the present invention without any problems. It is possible to use a heat-sensitive transfer recording medium alone as an adhesive layer, and to provide one or more heat-melting coloring material layers obtained in the present invention using the novel heat-sensitive transfer recording medium of the present invention. preferable.

As the support for use in the thermal transfer recording medium of the present invention, a support that is rich in thermal rigidity (heat-resistant strength), dimensional stability, and smoothness may be selected and used. Specifically, as heat resistance strength, it has both toughness and dimensional stability that do not soften or plasticize due to the heating temperature of a heat source such as a thermal head, and the surface smoothness is a color containing a heat-fusible substance on the support. It is desirable that the material layer has sufficient smoothness to exhibit a good thermal transfer rate (high print density and high resolution).

Examples of this include papers such as old paper, condenser paper, laminated paper, and coated paper; resin films such as polyethylene, polyethylene terephthalate, polyester, polystyrene, polypropylene, and polyamide; paper-resin film composites; and aluminum foil. Metal films such as aluminum and metal foils such as aluminum-resin film composites, paper-aluminum etc. metal foil composites, yam-metal foil-resin film composites, etc. can be suitably used.

The thickness of the support is most preferably 60μ or less, preferably 30μ or less, and particularly preferably 2μ to 20μ in order to obtain good thermal conductivity.

Further, the support used in the thermal transfer recording medium of the present invention is
There are no particular restrictions on the structure of the back side of the support, and it is arbitrary; for example, it may be a support that has a -m type backing layer such as an anti-bronching layer or an anti-sticking layer. .

[Examples] Examples of the present invention are shown below, but the invention is not particularly limited, and the terms % and parts shown in the examples below mean % by weight and parts by weight, respectively.

Example 1 The following coloring material N coating composition was directly coated onto a 3.5 μm thick polyethylene terephthalate film support using the true melt coating method so that the film thickness was 10 μm. Thermal transfer recording medium trial i1. l(8
A ribbon-shaped specimen) A with a width of mm was obtained.

Further, the colorant layer alone applied to the thermal transfer recording medium was found to have appropriate hardness and toughness, and had an elongation property of about 50% or more.

A new styrene-ethylene-butylene-styrene bronc copolymer resin containing 15% polystyrene (Shell Chemical Company product G [-1) is created by placing a crystalline ethylene-butylene rubber bronc in the intermediate rubber bronc.
: 8 parts paraffin wax (softening point 64°C) HN P-3F manufactured by Hiki Seirosha 20 parts microcrystalline wax (softening point 80°C) manufactured by Hiki Seirosha 111-M1c-1070: 56.8 parts Carbon blank (Paint grade) Mitsubishi Chemical Industries product MA100: 15 parts Benataerythrityl-tetrakis [3-(3,5-di-1-butyl-4-
Hydroxyphenyl) propionate] Anti-aging agent
= 0.2 parts This thermal transfer recording medium sample A was coated with an applied energy of 0.5 using a thermal printer (equipment with a built-in thermal head with a heating element density of 16 DoL/mm).
mj/Dot, commercially available high-quality paper (Benk smoothness 1)
00sec) and copy paper (Benk smoothness 30sec)
The recording (printing) test was repeated twice on each piece of bamboo.

In addition, using the gi for which printing was completed in Example 1 (the gi printed out in Example 1 and provided with the printed recording transfer image),
Table 1 shows the results of two 360° bending tests and a nail peeling test.

Example 2 In Example 1, a new styrene-ethylene-butylene-styrene block copolymer resin having a crystalline ethylene-butylene rubber block in the intermediate rubber block and containing 15% polystyrene (Shell Chemical Co., Ltd.) Product CR-1
) has an amorphous ethylene-butylene rubber block in the intermediate rubber block, and a styrene-ethylene-butylene-styrene block copolymer resin containing 13% polystyrene (Krayton G165, a product of Shell Chemical Co.)
7X)! 00 parts of crystalline low-molecular-weight polyethylene (Mitsui Petrochemicals, Mikata Ha-Iwx 220P with a molecular weight of 1.000 determined by the viscosity method) was added to nitrogen using a peroxide catalyst (hendyl peroxide). A new styrene-ethylene-butylene-styrene block copolymer resin obtained by carrying out graph 1-polymerization modification in an air stream and having crystalline polystyrene mostly on the side 1j) was used, except for the following example. The thermal transfer recording medium sample (8) of the present invention was prepared in the same manner as in 1.
A ribbon-shaped specimen) B with a width of mm was obtained.

The color material layer alone of the thermal transfer recording medium 13 was found to have appropriate hardness and toughness, and had an elongation property of about 10% or more.

Using this thermal transfer recording medium sample B, a printing test was conducted using a thermal printer in the same manner as in Example 1, a 360° bending test was conducted twice using the paper on which printing was completed in Example 2, and a nail The results of the peel test are listed in Table-1.

Comparative Example 1 In Example 1, a new styrene-ethylene-butylene-styrene block copolymer resin (a product of Shell Chemical Company (': R
-1) Use ethylene vinyl acetate copolymer (Evaflex #410, manufactured by San Jt Polychemical Co., Ltd.)17
A comparative thermal transfer recording medium sample (
A ribbon-shaped test specimen with a width of 8 mm was obtained, but as it had almost no adhesion to the support, it was impossible to use it for testing as it was. Therefore, in this comparative example, ethylene-ethyl was added to the support in advance. An acrylate copolymer (NIJC6070 manufactured by Nippon Unicar Co., Ltd.) solution was applied and dried to a film thickness of 1. A comparative thermal transfer recording medium sample (a ribbon-shaped test piece with a width of 8 mm) C was obtained in the same manner as in Example 1 via the adhesive layer of OIIm.

Using this thermal transfer recording medium sample C, a printing test was carried out with a thermal printer in the same manner as in Example 1, and a 360° bending test was carried out twice using the paper on which printing had been completed in Comparative Example 1.
The results of the nail peeling test are shown in Table 1.

Table-1 360° bending ◎: Print transfer image force q Rireya certain IF, f
(reflection density retention rate 95%)
that's all).

O: Very slight print transfer (Kanbakusureya!, one effect was retained.

(Shaku) [Temple collapse rate 80% Shishi L].

×: Severe print transfer image strength III and peeling were observed.

(Reflection density retention rate 70% or less).

◎: Print transfer (reduced color, 21 kids, almost no fading, no fading (reflection density retention rate 95% or more)
.

O: Slight cracking, 1kfdl, and fading of the printed transfer image were observed (reflection density retention rate of 80% or more).

×: Terrible print transfer image strength q or 1! Hooves and sores were observed.

(Reflection density retention rate 70% or less).

As is clear from the results in Table 1 above, sample A of the present invention
, l'3, the resolution of the print transfer image from the first to the second time is good even when applied to high-quality paper with a Henk smoothness of 100 seconds as well as copy paper with a Beck smoothness of 30 seconds. High-density transfer was possible with low-energy printing, but in Comparative Sample C, the density drop from the first to the second printing was large, even though the test was performed through an adhesive layer, which is a problem. I could hear it.

Furthermore, from the results of the mechanical durability of the printed transfer image, samples A and B of the present invention showed that the transferred print body had excellent towability and adhesion, resulting in high printing durability and reliability. but,
Comparative sample C had extremely low print durability and reliability due to the originally hard and brittle nature of the transfer print.

Example 3 In Example 1, samples of thermal transfer recording media were obtained by varying the roughness of the coloring material layer (applied as a dispersion using Daysilver) as described below.

A new styrene-ethylene-butylene-styrene block copolymer resin with a crystalline ethylene-butylene rubber block in the intermediate rubber bronch and containing 15% polystyrene (Shell Chemical Co. product GR-3)
: 10 parts Ethylene-ethyl acrylate copolymer (containing 17% ethyl acrylate) (Mitsui Polychemicals product Evaflex-EEA, A-707): 5 parts Oxidized wax (Nippon Jujusha product NPS9125): 20
Part Microcrystawanwanx (softening point 84'C) Nippon J, lf Rousha Co., Ltd. Crystal Hi-Mic-1080 = 50 parts Carbon blank (paint grade) Mitsubishi Chemical Industries product MA200: 15 parts This thermal transfer recording medium sample The recording (printing) test was repeated twice on copy paper (Beck smoothness: 30 seconds) in the same manner as in Example 1.

Table 2 shows the results of two 360° bending tests and a nail peeling test using the printed paper.

In addition, in Example 3, ethylene-ethyl acrylate copolymer was used, and in Table 2, ethylene-vinyl acetate (=Ipoly Gemical Co., Ltd.'s Fissile Evaflex EVA, #410) was used.
In F of Table 1-2, amorphous styrene-nitylene-butylene-styrene block copolymer resin (Asahi Kasei +1-
1052), G in Table 2 was changed to oxidized wax (Memoto Seisaku NPS9125), and 11 in Table 2 was changed to carnauba wax. (I got it.

Using these thermal transfer recording medium samples E to H, recording (printing) tests were repeated twice on copy paper (Beck smoothness: 30 sec) in the same manner as in Example 1.

Table 2 shows the results of two 360° bending tests and nail P and lI separation tests using the printed paper.

In addition, each sample was subjected to a bronking property test (a film sample with a thickness of 5 μm was stacked with a polyethylene terephthalate film, and was left at 40'C/9.5%RH for 1 day under a load of 15 gr/c rrl 2 and then taken out. Table 2 also shows the results of the anti-blocking test method in which the film was peeled off by peeling.

Table-2 Explanation of symbols [Mechanism details of printed transfer image) Durability] 360° bending ◎: Print transfer image force q rubya ff1lF
, l[ was hardly observed (reflection density retention rate 9
5% or more).

◯: Very slight print transfer image strength (9) and peeling force were observed.

(Reflection density retention rate 80% IN or above).

E! ', lN1 ◎: Print transfer recommended?
Il! , almost no smearing was observed (retention rate of 11 concentration of 95% or more).

O: Very slight print transfer image strength illumination, 71 rule, and fading were observed. (80% or more of anti-1.k degree fungal potato kernels).

[[1υ old fruit] Very good; r4 order very clear, optical reflection
el'B<1. 0 or more, and the second concentration decrease is more than 10% (p).

Good: Printing is clear, optical resistance is 0.9 or higher, and the second density drop is within 20%.

As is clear from the results in Table 2, the thermal transfer recording properties of the samples of the present invention are high in density and can be printed multiple times, even when the color material layer is directly provided on the support. It also has excellent blocking resistance, and it can be seen that the mechanical durability of the printed transferred image after printing is particularly excellent, with a density retention rate of at least 80% at the minimum.

Also, no similar inconvenient problems occurred during testing with a thermal printer.

Example 4 A styrene-ethylene-butylene-styrene block copolymer resin containing an amorphous ethylene-butylene rubber block as an intermediate rubber block and containing 13% polystyrene (
Shell Chemical Company product Kraton G-1657X) 1
00 parts, 35 parts of crystalline low molecular weight polyethylene (Mitsui Petrochemicals, Mitsui Highwanx 220P with a molecular weight of 92,000 determined by the viscosity method) was grafted in a nitrogen stream using a peroxide catalyst (benzoyl peroxide). 20 parts of a new styrene-ethylene-butylene-styrene block copolymer resin obtained by polymerization modification, most of which has crystalline polystyrene in its side chains, and microcrystalline wax (softening point 84°C) Crystal Hi-Mic-1 manufactured by Seirosha
60 parts of 080, 10 parts of Hiki Seirosha product NPS9125, oxidized wax (freezing point 63°C), and 1 part of carbon black.
The heat-melting coloring material using the novel heat-sensitive transfer recording medium of the present invention consisting of 0 parts was laminated as the first layer on the support to a film thickness of 5 μm by hot melt coating method, and then the same coloring material as used in Example 1 was applied. The novel coloring material of the present invention is made up of two layers obtained by applying a heat-melt coloring material using the novel heat-sensitive transfer recording medium of the present invention as a second layer with a film thickness of 5 μm using the true melt coating method (total of 10 μm). A thermal transfer recording medium sample (a ribbon-shaped test piece with a width of 8 mm) K was obtained.

Using this thermal transfer recording medium sample K, recording (
As a result of repeating the printing test three times, a reflection density ff of 10.98 was obtained in the first test and 0.65 in the third test.

In addition, using the printed paper, we conducted two 360° bending tests and a nail peeling test, and the results were good with almost no fading or peeling of the characters.

In addition, blocking property test (5 μm thick film sample I)
t Stacked with polyethylene terephthalate film, under a load of 15gr/cm2, 40'C/95%RH
So, did you take it out immediately after releasing it for a day? No abnormality was observed as a result of conducting the 7-pronging resistance test method.

Also, no similar inconvenient problems occurred during testing with a thermal printer.

From these results, it was found that the novel thermal transfer recording medium of the present invention may be formed by forming two coloring material layers directly on the support.

[Effects of the Invention] According to the present invention, low-energy printing is possible, the print density decreases little with respect to the number of uses, and a clear high resolution is exhibited, and plain paper with poor surface smoothness and film with unevenness can be printed. In addition to the above-mentioned performance, the mechanical durability of the transferred printed material is extremely excellent, which was not achieved with conventional products, and the toughness of the paper or uneven film that is the transfer paper is excellent. It is possible to obtain a transfer print with toughness and adhesiveness that fully corresponds to the characteristics of the transfer print, and prevents discoloration of the transfer print.
It is possible to obtain an effect that does not cause any fading or decrease in density over time.

Furthermore, the thermal transfer recording medium of the present invention has excellent blocking resistance.

Claims (1)

[Claims] 1. In a heat-sensitive transfer recording medium having a heat-melting coloring material layer directly on a support, the heat-melting coloring material layer has a polystyrene end block, and a crystalline intermediate block has a polystyrene end block. New styrene-ethylene with ethylene-butylene rubber block
A novel thermal transfer recording medium characterized by containing a butylene-styrene block copolymer resin and one or more heat-melting substances selected from the following compound group. Compound group: Animal-based waxes Plant-based waxes Mineral-based waxes Petroleum-based waxes Synthetic hydrocarbon-based waxes Modified waxes 2. Polystyrene content ranges from 5 to 45% by weight, and the intermediate block body consists of a crystalline ethylene-butylene block. A novel thermal transfer recording medium according to claim 1, characterized in that a novel styrene-ethylene-butylene-styrene block copolymer resin is used. 3. Use of a new styrene-ethylene-butylene-styrene block copolymer resin in which the intermediate block is composed of a crystalline ethylene-butylene block, and the intermediate block contains a high proportion of crystalline polyethylene of at least 60% by weight. A novel thermal transfer recording medium according to claim 2, characterized in that: 4. A novel styrene-ethylene-butylene having a weight average molecular weight in the range of 5,000 to 200,000, a polystyrene content in the range of 5 to 45% by weight, and an intermediate block having a crystalline ethylene-butylene block. A novel thermal transfer recording medium according to claim 3, characterized in that a styrene block copolymer resin is used. 5. A novel styrene-ethylene-butylene having a weight average molecular weight in the range of 5,000 to 200,000, a polystyrene content in the range of 5 to 45% by weight, and an intermediate block having a crystalline ethylene-butylene block. 5. A novel thermal transfer recording medium according to claim 4, characterized in that a styrene block copolymer resin is used in the thermal transfer recording medium in an amount of at most 30% by weight. 6. At least one or more heat-melting substances selected from animal waxes, vegetable waxes, mineral waxes, petroleum waxes, synthetic hydrocarbon waxes, and modified waxes are added to the thermal transfer recording medium. 6. A novel thermal transfer recording medium according to any one of claims 1 to 5, characterized in that it contains 70% by weight or more as an essential component. 7. A novel thermal transfer recording medium according to any one of the claims, characterized in that the elongation rate of a molded product of the thermal transfer recording medium alone is at least 30% or more. 8. A novel thermal transfer recording medium according to any one of the claims, characterized in that the thermal transfer recording medium alone has a melt viscosity in the range of 5 to 2,000 cps at 110°C. 9. A novel thermal transfer recording medium according to any one of the claims, characterized in that the softening point temperature of the thermal transfer recording medium alone, measured by the ring and ball method, is in the range of 60°C to 130°C. 10. Ethylene-vinyl acetate copolymer resin with a vinyl acetate content of 28% by weight or less, polyethylene glycol diester with a weight average molecular weight in the range of 400 to 30,000, and ethylene-ethyl acrylate copolymer with a ethyl acrylate content of 35% by weight or less resin, aromatic tackifier resin, alicyclic tackifier resin, rosin ester tackifier resin, crystalline polyester resin, styrene-ethylene-butylene-styrene block copolymer resin consisting of an amorphous intermediate block body, The softening point of the resin selected from styrene-butadiene-styrene block copolymer resin and styrene-isoprene-styrene block copolymer resin is 13 as measured by ring and ball method.
Claim 1, characterized in that the heat-sensitive transfer recording medium contains at most 10% by weight of one or more heat-melting resin substances exhibiting a temperature of 0°C or less. A new thermal transfer recording medium.