JPH0199883A - Thermal transfer recording medium - Google Patents

Abstract

PURPOSE:To prevent a lowering in the blocking resistance and an increase in be torque of unwinding a thermal transfer recording medium, by forming a heat-softening layer containing a coloring material, a heat-meltable substance, and a tackifier which is liquid at normal temperature on a support of be recording medium. CONSTITUTION:A thermal transfer recording medium is prepared by forming at least one heat-softening layer containing a coloring material, a heat-meltable substance, and a tackifier which is liquid at normal temperature on a support. Examples of the support include paper, resin film and metallic sheet, and its thickness is preferably about 1.5-15mum. Examples of the coloring material include ordinary inorganic and organic pigments and dyes, and its content in be heat-softening layer is preferably about 5-30wt.%. Examples of the heat- meltable substance include vegetable and animal waxes, and its content in the heatsoftening layer is preferably about 50wt.%. suitable examples of the tackifier include one which is liquid at 20-30 deg.C, e.g., rosin.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] Unreleased IJ1 relates to a thermal transfer recording medium with improved print quality. More specifically, the present invention relates to a thermal transfer recording medium that allows printing of good quality even when printing energy is low.

[Prior art and its problems] Thermal transfer recording media are widely used for printing in word processors and the like. This heat-sensitive transfer recording medium generally consists of a support and a heat-softening layer laminated on the support. This heat-softening layer is configured by being dispersed in a colorant such as carbon black or a dispersion binder such as a heat-fusible substance.

During thermal transfer, the dispersion binder quickly melts or softens due to the heat from the thermal head, separates from the surface of the support, and transports the coloring material to the surface of the transfer medium such as paper. It has the effect of fixing the coloring material on the surface of the medium. From the perspective of fixing the coloring material onto the transfer medium, the dispersion binder contains a substance that has adhesive properties to the transfer medium in addition to the above-mentioned heat-melting substance, thereby improving the coloring material's coverage. The transferability to the transfer medium is improved. Attempts have already been made to use a tackifier that is solid at room temperature, such as petroleum resin, in the heat-softening layer. By utilizing the adhesive force developed when the tackifier, which is solid at room temperature, returns from a molten state to a solid state, the heat-softening layer has good adhesion to the transfer medium.

However, since this heat-softening layer also has strong adhesion to the support, the peelability of the heat-softenable layer from the support deteriorates, resulting in a new problem in that printing quality is not sufficiently improved. arise. Furthermore, good adhesion with the support is achieved by bringing the heat-softening layer of the rolled heat-sensitive transfer recording medium and the support into a young state (a so-called blocking state), which causes the heat-sensitive transfer recording medium during transfer. If the unwinding torque becomes high, it may also cause problems.

In this way, although tackifiers have the ability to provide good printability to thermal transfer recording media, in reality, they have the above-mentioned new problems. Because of this, they are rarely used, or only in very low concentrations, and the excellent properties of tackifiers are not fully exploited.

Especially in recent years, when printing speeds have become extremely high and devices themselves have become smaller, printing quality is affected by the blocking resistance of thermal transfer recording media and the releasability of heat-softening layers. The impact on printing is greater than when printing at low speeds using conventional large devices. Therefore, tackifiers are becoming more difficult to use than ever before.

[Object of the Invention] An object of the present invention is to provide a thermal transfer recording medium capable of printing with excellent quality.

More specifically, 1. The present invention provides a thermal transfer recording medium that can perform printing of excellent quality without reducing blocking resistance or increasing unwinding torque. SUMMARY OF THE INVENTION An object of the present invention is to provide a thermal transfer recording medium that can print at a very high printing speed and that can print with excellent quality even when using a small device with low printing energy.

[Means for achieving the above object] A first configuration of the present invention for achieving the above object includes a support and at least one layer containing a coloring material and a heat-melting substance laminated on the support. The present invention is a thermal transfer recording medium having a heat-softening layer, characterized in that the heat-softening layer contains a tackifier that is liquid at room temperature.

Furthermore, a second configuration of the present invention provides a thermal transfer recording medium having a support and at least one heat-softening layer containing a coloring material and a heat-melting substance laminated on the support. The present invention is a thermal transfer recording medium characterized in that the layer contains a tackifier that is liquid at room temperature and a polyoxyethylene derivative.

The uninvented heat-sensitive transfer recording medium has a support and a heat-softening layer laminated on the support.

1. Support 1. The support used in the thermal transfer recording medium of the present invention preferably has heat-resistant strength, high dimensional stability, and high surface smoothness.

Examples of materials for forming the support include plain paper and paper.
Papers such as sider paper, laminated paper and coated paper,
Examples include resin films such as polyethylene, polyethylene terephthalate, polystyrene, polypropylene and polyimide, composites of paper and resin films, and metal sheets such as aluminum foil. In particular, in the present invention, it is preferable to use resin films, composites of paper and resin films, and metal sheets, which have high surface smoothness and are difficult to penetrate with a liquid tackifier at room temperature. Particularly preferred is the use of resin films having good thermal conductivity and heat resistance, such as polyethylene terephthalate.

The thickness of the support is usually 60 uLm or less in order to obtain good thermal conductivity. In the present invention, especially 1
．． Preferably, the length is within the range of 5 to 154 m. In order to adjust the adhesion with the heat-softening layer, etc., on the surface of the support,
Surface treatments such as corona discharge treatment, glow discharge treatment, other electric shock treatments, flame treatment, ultraviolet irradiation treatment, oxidation treatment, and saponification treatment may be performed, and rough undercoating processing may be performed.

The support may also have a backing layer on one side.

-Thermo-softening layer- The heat-sensitive transfer recording medium of the present invention has a heat-softening layer on the above-mentioned support.

The heat-softening layer is a coloring material and a heat-melting substance! 1 and a thermoplastic resin, and in the thermal transfer recording medium of the present invention, this layer contains a tackifier that is liquid at room temperature.

As coloring materials that can be used in the thermal transfer recording medium of the present invention, commonly used pigments and dyes such as j# pigments and organic pigments can be used.

Examples of inorganic pigments are titanium dioxide and carbon graphite.

Mention may be made of tungsten, zinc oxide, Prussian blue, cadmium sulphide and iron oxide as well as chromates of lead, zinc, barium and calcium. Examples of organic pigments include azo, thioindigo, anthraquinone,
These include anthurone and triphenedioxazine pigments, vat dye pigments, phthalocyanine pigments, metal (eg copper) phthalocyanines and their derivatives, and quinacridone pigments.

Examples of organic dyes include acid dyes, direct dyes, disperse dyes, oil-soluble dyes and metallized oil-soluble dyes.

The content of the coloring material in the heat-softening layer is usually .

It is within the range of 5 to 30% by weight.

Specific examples of the heat-melting substance used in the heat-sensitive transfer recording medium of the present invention include vegetable waxes such as carnauba wax, wood wax, auriculie wax, and nispar wax.

Animal waxes such as beeswax, insect wax, shellac wax and spermaceti wax, paraffin wax, microcrystalline wax,
Petroleum waxes such as polyethylene wax, ester wax, and acid wax; Waxes such as acupuncture wax such as montan wax, oshikerite, and ceresin; Higher fatty acids such as valmitic acid, stearic acid, margaric acid, and behenic acid; valmityl alcohol, stearyl alcohol , higher alcohols such as behenyl alcohol, marganyl alcohol, myricyl alcohol and eicosanol, higher fatty acid esters such as cetyl valmitate, myricyl valmitate, cetyl stearate and myricyl stearate, acetamide, propionic acid amide, valmitic acid amide, stearic acid Examples include amides such as amides and amide waxes, and higher amines such as stearylamine, behenylamine and valmitylamine, which may be used alone or in combination.

4. In the present invention, by using a combination of hard heat-melting substances such as carnauba wax, ester wax and oxidized polyethylene wax and soft heat-melting substances such as paraffin wax, high quality products can be obtained. Printing can be performed. In this case, it is preferable to make the content of the soft heat-fusible substance higher than the content of the hard heat-fusible substance.

What is the content of the heat-melting substance in the heat-softening layer?

It usually accounts for 50% or more of the total weight of this layer. If the amount is less than 50% by weight, the releasability of this layer during transfer may decrease. In particular, in the present invention, this content is set to 60
Printing quality is improved by increasing the amount by weight% or more.

The heat-softening layer of the thermal transfer recording medium of the present invention contains a tackifier that is liquid at room temperature (hereinafter sometimes simply referred to as "liquid tackifier").
In particular, in the present invention, at least 20 to 3
Preferably, tackifiers are used which remain in a liquid state at temperatures within the range of 0°C.

The liquid tackifier used in the present invention is a hydrocarbon compound having a polar group such as a hydroxyl group or a carboxyl group, which exhibits adhesive strength when used alone or in combination with other components. It is.

Examples of liquid tackifiers such as unmodified or modified rosin tackifiers include rosin tackifiers, water-added rosin tackifiers, rosin maleic tackifiers and rosin phenolic tackifiers. Examples include tackifiers, terpene-based tackifiers and modified tackifiers thereof, and petroleum-based tackifiers and modified tackifiers thereof.

By adding such a liquid tackifier, the heat-softening layer has good viscosity against the transfer medium such as paper, or has good viscosity against the surface of the support with high surface smoothness. It has the characteristic of not exhibiting stickiness.

In the present invention, the content of the liquid tackifier in the heat-softening layer is 10% based on the total weight of the components forming this layer.
It is preferable to make it less than % by weight. If the content of the liquid tackifier is higher than 10% by weight, the adhesive strength between the support and the heat-softening layer may develop, resulting in a decrease in high-speed printing performance. In particular, in the present invention, by setting this content within the range of 0.5 to 8% by weight, the unwinding torque of the thermal transfer recording medium can be particularly reduced.

The heat-softening layer of the heat-sensitive transfer recording medium of the present invention may further contain a thermoplastic resin.

Examples of thermoplastic resins used in the present invention include ethylene copolymers, polyamide resins, polyester resins, polyurethane resins, polyolefin resins, acrylic resins, vinyl chloride resins, cellulose resins, and ionomer resins. resins such as diene copolymers, natural rubber, styrene-butadiene rubber, elastomers such as isoprene rubber and chloroprene rubber, phenolic resins, cyclopentadiene resins, and aromatic hydrocarbon resins with a softening point of 50 to 150°C. High molecular compounds can be mentioned.

When thermoplastic resins are used, among the above, acrylic resins, diene copolymers and ethylene copolymers are preferably used, especially liquid tackifiers and ethylene copolymers such as ethylene-vinyl acetate copolymers. By using it in combination with coalescence, it is possible to obtain a thermal transfer recording medium with particularly good high-speed printing quality.

Preferred thermoplastic resins will be explained below.

Examples of acrylic resins include acrylic resins obtained by polymerizing monobasic carboxylic acids such as (meth)acrylic acid or their esters and at least one type of compound that can be copolymerized with these. can.

Examples of carboxylic acids or esters thereof used in this case include (meth)acrylic acid, (meth)acrylic acid methyl ester, (meth)acrylic acid ethyl ester, (
(meth)acrylic acid isopropyl ester, (meth)acrylic acid butyl ester, (meth)acrylic acid isobutyl ester, (meth)acrylic acid amyl ester, (meth)acrylic acid hexyl ester, (meth)acrylic acid octyl ester, (meth)acrylic acid octyl ester Acrylic acid-2-ethylhexyl ester, (meth)acrylic acid decyl ester, (
Mention may be made of meth)acrylic acid dodecyl ester, (meth)acrylic acid hydroxyethyl ester and (meth)acrylic acid human xyethyl ester. Further, examples of the above copolymerizable compounds include vinyl acetate, vinyl chloride, vinylidene chloride, maleic anhydride, fumaric anhydride, styrene, 2-methylstyrene, chlorostyrene, acrylonitrile, vinyltoluene, N-methylol ( Examples include meth)acrylamide, N-butoxymethyl(meth)acrylamide, vinylpyridine and N-vinylpyrrolidone, and these may be used alone or in combination of two or more.

As the diene copolymer, for example, butadiene
Styrene copolymers, butadiene-styrene-vinylpyridine copolymers, butadiene-acrylonitrile copolymers, chloroprene-styrene copolymers and chloroprene-acrylonitrile copolymers can be mentioned.

Examples of the ethylene copolymer include ethylene-vinyl acetate copolymer, ethylene-ethyl acrylate copolymer, ethylene-methyl methacrylate copolymer, ethylene-isobutyl acrylate copolymer, and ethylene-acrylic acid copolymer. Polymers, ethylene-vinyl alcohol copolymer, ethylene-vinyl chloride copolymer and ethylene-acrylic acid gold salt copolymer can be mentioned.

When using thermoplastic resin, thermal IJ in the thermosoftening layer
The content of T-plastic resin is usually 30% by weight or less based on the total weight of this layer. If the amount exceeds 30% by weight, the peelability of the heat-softening layer from the support during thermal transfer may become insufficient.

The heat-sensitive transfer recording medium of the present invention has a heat-softening layer having the above-mentioned components, so that printing can be performed with good quality at normal speed and energy, and unwinding torque can be reduced. Of course, it is possible to print with good quality even during high-speed printing, but by adding a polyoxyethylene derivative to the heat-softening layer of the thermal transfer recording medium of the present invention, the printing performance at high speeds is improved. In addition, it is possible to further reduce the unwinding torque.

The polyoxyethylene derivative used in the present invention is a compound having a polyoxyethylene chain represented by the following general formula in its molecule.

-(-CH2CH20-)l,- However, in the above formula, n represents an integer of 2 or more.

The compound having a polyoxyethylene chain is preferably a substance that is solid at room temperature and has a melting point in the range of 30 to 120°C, and particularly preferably a substance having a melting point in the range of 40 to 100°C.

The polyoxyethylene derivative in the present invention will be explained in more detail.

Polyoxyethylene derivatives that can be used in the present invention include polyethylene glycol and polyethylene glycol derivatives.

The polyethylene glycol derivative used in the present invention can usually be produced by reacting the - or 'two alcoholic -0H groups of polyethylene glycol with various organic compounds according to a conventional method.

In this case, the obtained polyethylene glycol derivative is
Depending on the type of organic compound used, the polyethylene glycol derivative may contain ether bonds, ester bonds, bonds with sulfur atoms or nitrogen atoms, urethane bonds, and other bonds. and those containing an ester bond are preferred.

As a polyoxyethylene derivative, the molecular weight of the polyoxyethylene chain portion in the molecule is 200 to 20,000.
Preferably, it is within the range of .

Next, specific examples of polyoxyethylene derivatives used in the present invention will be given.

(1) Polyethylene glycol -(-CH2Cl,0-)- The average molecular weight of the spelling unit part expressed as 100~
Within the range of 20,000 (specifically, 20,000.

12000, 9000.1000.400 $5 and 100).

(2) Mono- or diester derivatives of polyethylene glycol In particular, when derived from a fatty acid, the fatty acid preferably has a carbon number of j0 to 50, and particularly preferred fatty acids have a carbon number of 10 to 19. be.

Specific examples of these fatty acids include capric acid, undecanoic acid, lauric acid, tridecanoic acid, myristic acid, pentadecanoic acid, palmitic acid, margaric acid, stearic acid, nonadecanoic acid, arachidic acid, heneicosanoic acid, behenic acid, and tricosanoic acid. Examples include mono- or diester derivatives such as lignoceric acid. Among these, preferred are mono- or diester derivatives of nonadecanoic acid, arachidic acid, heneicosanoic acid, behenic acid, tricosanoic acid and lignoceric acid.

The mono- or diester derivatives of polyethylene glycol include linear monoenoic acids, di-, tri- or tetraenoic acids, monosynthetic fatty acids, tertiary fatty acids, branched fatty acids, dimer acids, dibasic acids, polybasic acids, oxycarboxylic acids,
Examples include fatty acid chlorides, fatty acid anhydrides, polycarboxylic acids, and other compounds containing one or more carboxyl groups in the molecule. Moreover, regarding diester derivatives, the diester moieties may be the same or different.

More specifically, polyethylene glycol monobehenate (PEG 4
000) Polyethylene glycol distearate (PEG 6
000) Polyethylene glycol monopalmitate (PEG
600) polyethylene glycol dibehenate (PEG 14 [100)] polyethylene glycol laurinate (PEG 100), etc.

The numerical values written in parentheses at the bottom of the above compounds are as follows:
-(CH,CH20) Indicates the average molecular weight of the n portion (PEG portion) (the same applies hereinafter).

(3) Ether derivatives of monoalkyl and arylalkyl ethers of polyoxyethylene ether, compounds in which one -0) I group of polyethylene glycol is derived from an ether) The above ethers preferably have a carbon number of 6 or more, Particularly preferred are alkyl and alkylaryl polyoxyethylene ethers having 18 to 50 carbon atoms.

The alkyl group in these may be linear or branched, or may be a substituted product of a halogen atom.

Furthermore, polyoxyethylene ethers of unsaturated hydrocarbons, synthetic alcohols, oxycarboxylic acids, and nitrogen-containing sulfur compounds can also be used.

Specifically, polyethylene glycol mono-P-nonylphenyl ether (PEG 900) polyethylene glycol monobehenyl ether (PEG 6000) polyethylene glycol monocetyl ether (PEG
200) Polyethylene glycol monooleyl ether (PEG
4000).

(4) The ether or ester derivative of the monoether-conducting conductor in (3) above, that is, the remaining 10H group of the monoalkyl or arylalkyl aryl ether derivative of the polyoxyethylene ether in (3) above, is ether-derived or esterified. It was induced.

Ester induction in this case is based on the case (2) above, and ether induction is based on the case (3) above.

in particular.

Monobehenate of polyethylene glycol mono-P nonylphenyl ether (PEG 800) Monostearate of polyethylene glycol monostearyl ether (PEG 900 (1) Polyethylene glycol dibehenyl ether (PEG 6000)
) Polyethylene glycol monooleyl ether monobehenyl ether (PEG 4000) and the like.

(5) Polyoxyethylene ether derivatives of polyhydric alcohols, that is, compounds having two or more alcoholic -○H groups in one molecule, such as glycerin, polyglycerin, propylene glycol, pentaerythryl, sorbitan (l, 5- sorbitan, 1.4- or 3.6-sorbitan, isosorbite), mannitol, and other polyvinyl alcohols (poval) with a molecular weight of 800 or less; This is a polyoxyethylene derivative of a compound in which the polymer is ester-derived and/or ether-derived according to (2) and/or (3) above.

This polyoxyethylene ether derivative has one or more polyoxyethylene chains in its molecule, and one end of the polyoxyethylene chain is ester-derived according to (2) and/or (3) above. and/
Or ether-derived ones are preferred.

Further, it may have a structure in which two or more sets of polyhydric alcohols are bonded together, or it may have a structure in which polyoxyethylene chains are crosslinked.

Specifically, glycerin polyoxyethylene monostearate chrycerin di(polyoxyethylene monostearate) sorbitan monobehenate polyoxyethylene monobehenyl ether butyl alcohol polyoxyethylene oleate polypropylene glycol and polyoxyethylene Glycol block copolymers Polyglycerin Polystearate Polyoxyethylene ether Pentaerythritol Distearyl ether Polyoxyethylene ether Behenate Sorbitan ester Polyoxyethylene ether Pentaerythritol Polyoxyethylene ether Polyglycerin ester Polyoxy Examples include polyoxyethylene ether ester of ethylene ether butyl alcohol ester, polyoxyethylene ether of mannitol ester, and the like.

(6) Specific examples of polyoxyethylene derivatives of molecules containing sulfur atoms or nitrogen atoms include alkylthiopolyoxyethylene ethers, polyoxyethylene fatty acid amides, and polyoxyethylene alkylamines.

(7) Specific examples of polyoxyethylene derivatives of polymers or copolymers include alkylaryl formaldehyde condensation polyoxyethylene ether, polyoxyethylene ether ester of copolymer, and polyoxyethylene ether of α-olefin maleic anhydride copolymer. Examples include derivatives.

(8) Synthetic polymers such as polyester and polyurethane and polyoxyethylene block polymers (9) Compounds with anionic properties Specific examples include carboxylates of polyoxyethylene alkyl (allyl) ethers and sulfuric acids of polyoxyethylene fatty acid esters. salt, sulfate of polyoxyethylene alkyl (allyl) ether, polyoxyethylene alkyl (allyl) ether
Examples include polyoxyethylene-containing anionic activators such as phosphates of allyl) ethers, polyoxyethylene alkyl(allyl)amide phosphates, and carboxylates of polyoxyethylene fatty acid esters.

(10) Specific examples of compounds with cationic properties include polyoxyethylene-containing cationic active agents and amphoteric surfactants such as alkyl (allyl) polyoxyethylene ether ammonium salts and polyoxyethylene hydroxy ammonium salts.

Among the polyoxyethylene derivatives (1) to (10), preferred are the mono- or diester derivatives of polyethylene glycol (2) and the ethers of monoalkyl and arylalkyl ethers of polyoxyethylene ether (3). It is a derivative. Among these, polyoxyethylene monobehenyl ether and polyoxyethylene distearyl ester are particularly preferred.

The content of the polyoxyethylene derivative in the heat-softening layer is 1 to 20% by weight based on the components forming the heat-softening and softening layer.
It is preferable to keep it within the above range; if it deviates from the above range, the effect of the addition of the polyoxyethylene derivative may not be effective. In particular, by controlling the content of the polyoxyethylene derivative within the range of 5 to 15% by weight, the unwinding torque can be effectively reduced.

The weight ratio of the liquid tackifier to the polyoxyethylene derivative in the heat-softening layer is usually 5:5 to 1.
: 9. In other words, when using a liquid tackifier and a polyoxyethylene derivative, the amount of the polyoxyethylene derivative should be the same or more than the amount of the liquid tackifier. By using the appropriate amount, the unwinding torque can be effectively reduced.

Note that the heat-softening layer is usually laminated directly on the support, but the heat-softening layer can be formed by, for example, two or more heat-softening layers having different contents of forming components such as polyethylene oxide derivatives. may be configured.

1. Method for preparing each layer - The heat-sensitive transfer recording medium of the present invention is prepared by a method of applying a coating liquid prepared by dissolving or dispersing components forming a heat-softening layer in an organic solvent (solvent coating method).

A method of heating this forming component to make at least a part of it into a molten state and applying this melt (hot melt coating method), and preparing an aqueous coating solution prepared by dispersing the forming component of this layer in water, It can be formed by applying a coating solution (water-based coating method) or the like using a common coating device.

The heat softenable layer has a dry thickness typically between 0.5 and 8.0 pm.
(preferably 1 to 4 pm). If it is thinner than 0.5 gm, scratch resistance may be insufficient, and if it is thicker than 8.0 pm, sensitivity may decrease.

-How to use- The thermal transfer recording medium of the present invention can of course be used satisfactorily as a normal thermal transfer recording medium, and can particularly be suitably used as a thermal transfer recording medium used in high-speed transfer.

[Example] In the Examples and Comparative Examples shown below, "parts" indicate "parts by weight."

(Example 1): The following heat-softening layer coating composition (I) was applied on a 1.5 pm polyethylene terephthalate film to a dry film thickness of 4.5 pm.
A heat-softening layer was formed by hot-melt coating to a thickness of 54 m, thereby producing a heat-sensitive transfer recording medium of the present invention.

・I Carnauba wax・・・・・・・・・・・・・・・・・・
...-15 parts paraffin wax [melting point 70°C]...
...58 parts ethylene-vinyl acetate copolymer...
...16 parts liquid tackifier...
・・・・・・・・・・5 parts carbon black・・・・
......16 parts (Comparative Example 1) Instead of the heat-softening layer coating composition (1) used in Example 1, the heat-softening layer described below was used. Coating composition (1-IC)
A thermal transfer recording medium was produced in the same manner as in Example 1 except that .

, l-1c Carnauba wax [same as above]・・・・・・・・・・・・1
Part 5 Paraffin wax [same as above]・・・・・・・・・
63 parts ethylene-vinyl acetate copolymer...
16 parts carbon black・・・・・・・・・・・・・・・
...... 16 parts (Comparative Example 2) Instead of the heat-softening layer coating composition (I) used in Example 1, the following heat-softening layer coating composition (1-2C) was used.
A thermal transfer recording medium was produced in the same manner as in Example 1 except that .

-1-2C Carnauba wax [same as above]・・・・・・・・・・・・1
5 parts paraffin wax [same as above]...
58 parts ethylene-vinyl acetate copolymer...
16 parts petroleum resin [melting point 70℃]・・・・・・・・・・・・
・・・・・・5 parts carbon black・・・・・・・・・・
......16 parts (Example 2) Instead of the heat-softening layer coating composition (1) used in Example 1, the heat-softening layer coating composition (n ) A thermal transfer recording medium of the present invention was produced in the same manner as in Example 1 except that the following was used.

■ Estherwa Tuxus [melting point 85℃]・・・・・・・・・1
0 part oxidized polyethylene wax・・・・・・・・・・・・
・20 parts [melting point 75°C] Paraffin wax [same as above] 41
Part Liquid tackifier・・・・・・・・・・・・・・・・・・
...Tripartite polyoxyethylene derivative...
・・・・・・10 parts (polyoxyethylene monostearate) carbon black・・・・・・・・・・・・・・・
......16 parts (Comparative Example 3) Instead of the heat-softening layer coating composition (■) used in Example 2, the heat-softening layer coating composition (II-C) described below was used.
A thermal transfer recording medium was produced in the same manner as in Example 2 except that .

・nc Ester wax [melting point 85°C] 10 parts Brewed polyethylene wax 20
Part [melting point 75°C] Paraffin wax [same as above] 44
Polyoxyethylene derivative・・・・・・・・・・・・
10 parts (polyoxyethylene monostearate) carbon black
16 copies [Evaluation] [Mu 11] The thermal transfer recording media obtained in the above Examples and Comparative Examples were printed on a commercially available high-speed printer (24-dot serial head, platen pressure: 200 g hat, applied energy: 25 mJ/
Print speed: 180DPI) Attach and record (
The printing quality was visually evaluated.

The results are shown in Table 1.

In Table 1, the meanings of the symbols are as follows.

Company-j　　　匪ヱ菫1 ◎・・・・・・Reproduces clear alpha heud.

○・・・・・・The reproduction of the alphabet is a little unclear.

×・・・・・・The reproduction of the alphabet is unclear.

The heat-sensitive transfer recording media obtained in the above Examples and Comparative Examples were placed in a cassette in a wound state, and the temperature was 50° C. and the humidity was 50° C.
%, and then the torque when pulling out the 1 mm roll of thermal transfer recording medium was measured.

The results are shown in Table 1.

(Raikou, hereafter in the margin) Table 1 [Effects of the Invention] During thermal transfer, the thermal transfer recording medium of the present invention is characterized by the fact that during thermal transfer, the tackifier, which is liquid at room temperature contained in the heat-softening layer, or the structure of the transfer medium Because it penetrates into the surface, it is possible to print with extremely high quality.

This tackifier, which is liquid at room temperature, does not exhibit tackiness to the support under normal conditions, so even when stored under normal conditions or under harsh conditions. Since there is little adhesion between the heat-softening layer and the support in the rolled state, the unwinding torque does not increase.

By using a tackifier that is liquid at room temperature in this way, it is possible to simultaneously improve the opposing properties of improved printing quality and improved blocking resistance, which were not possible with conventional solid tackifiers. Ru.

Furthermore, by improving printing quality and blocking resistance, by using the thermal transfer recording medium of the present invention, it is possible to print with good quality even in high-speed printing with low printing energy per dot. I'll come.

The above characteristics can be further improved by incorporating a polyoxyethylene derivative into the heat-softening layer. That is,
Polyoxyethylene derivatives are particularly useful because they effectively prevent printing and also improve the peelability of the heat-softening forming component from the support during printing and the penetration force into the transfer medium. Print quality improves during high-speed printing.

Claims (6)

[Claims] (1) In a thermal transfer recording medium having a support and at least one heat-softening layer containing a coloring material and a heat-melting substance laminated on the support, the heat-softening layer is liquid at room temperature. A thermal transfer recording medium characterized by containing a tackifier. (2) The heat-sensitive transfer recording medium according to claim 1, wherein the content of the tackifier that is liquid at room temperature in the heat-softening layer is 10% by weight or less based on the forming components of the heat-softening layer. . (3) In a heat-sensitive transfer recording medium having a support and at least one heat-softening layer containing a coloring material and a heat-melting substance laminated on the support, the heat-softening layer is liquid at room temperature. A thermal transfer recording medium comprising a tackifier and a polyoxyethylene derivative. (4) The heat-sensitive transfer recording medium according to claim 3, wherein the content of the tackifier that is liquid at room temperature in the heat-softening layer is 10% by weight or less based on the forming components of the heat-softening layer. . (5) The heat-sensitive transfer recording according to claim 3, wherein the content of the polyoxyethylene derivative in the heat-softening layer is within the range of 1 to 20% by weight based on the forming components of the heat-softening layer. Medium. (6) The weight ratio of the tackifier, which is liquid at room temperature, and the polyoxyethylene derivative in the heat-softening layer is 5:5 to 1.
The thermal transfer recording medium according to claim 3, which falls within the range of: 9.