JPH062432B2 - Sublimation type disperse dye thermal transfer recording type recording medium and method for producing the same - Google Patents

Description

The present invention relates to a recording medium in a sublimation type thermal transfer recording system.

[Conventional technology]

With the recent rapid spread of office automation, the number of color displays in personal computers, word processors, office computers, etc., which are the core of the office automation, has increased rapidly, and the demand for the practical use of a recording method from color signals has been rapidly increasing. In the field of dry copiers, there are strong demands for colorization.

Conventional color recording methods include a light pen method, a wire dot method, and an inkjet method, but each has drawbacks such as a low recording speed, noise, and clogging of minute nozzles through which ink is ejected. On the other hand, the sublimation type thermal transfer recording method does not generate any noise and the handling, maintenance,
It has features such as easy management. In addition, this method is a method of heating a transfer sheet coated with a sublimable dye with a thermal recording head to sublimate and transfer the dye to a recording medium to obtain color recording, so that the energy applied to the thermal head should be adjusted. Since the sublimation amount of the dye can be controlled by this, gradation expression is easy, and it is particularly advantageous in obtaining a full-color hard copy as compared with other recording methods. However, regarding this method, even if the recording principle and characteristics were announced as described above,
Under the present circumstances, a recording material excellent in color developability and color tone clarity by a sublimable disperse dye has not yet been developed, and there has been no case on the market, and its development has been strongly demanded.

[Object of the Invention]

An object of the present invention is to provide a recording material for dry transfer which is easily dyed with a sublimation type disperse dye in a sublimation type thermal transfer recording method and which is excellent in color developability and sharpness.

[Means for solving problems]

According to the present invention, 10 to 70 parts by weight of a crosslinker curable with active energy rays and at least one (meth) acrylic acid alkyl ester polymer on the surface of a substrate, the (meth) acrylic acid alkyl ester component Is contained in an amount of 50% by weight or more and the glass transition point Tg of the polymer is 90 to 30 parts by weight (selected so that the sum of both is 100 parts by weight). Film thickness cured by irradiation with energy rays 0.5 to
Provided is a sublimation type disperse dye thermal transfer recording type recording medium having a cured coating of 100 μm.

Further, according to the present invention, 10 to 70 parts by weight of a cross-linking agent curable by active energy rays, and at least one kind of (meth) acrylic acid alkyl ester polymer, wherein the (meth) acrylic acid alkyl ester component is 50% by weight. A coating composition comprising 90 to 30 parts by weight of a polymer having the above Tg of 0 ° C. or more (selected so that the sum of the two is 100 parts by weight) and a photopolymerization initiator is applied to one side of a substrate. Then, a method for producing a recording medium of a sublimation type disperse dye thermal transfer recording system is provided, which comprises forming a cured film having a film thickness of 0.5 to 100 μm by irradiating and curing with an active energy ray. .

According to the present invention, the surface of a substrate (preferably a film or paper) is coated with a coating composition containing the above-mentioned specific (meth) acrylic acid alkyl ester polymer and a crosslinking agent as main components, for example, 0.5 to 100 μm. It was found that a recording medium obtained by applying the above composition to a thickness of 2 and curing with an active energy ray was easily dyed with a sublimable disperse dye and was excellent in color developability and sharpness.

The (meth) acrylic acid alkyl ester polymer used in the present invention is a polymer of (meth) acrylic acid alkyl ester having a substituted or unsubstituted alkyl group or a copolymer thereof. Examples of the copolymer monomer include styrene and (meth) acrylic acid. Examples of the substituent of the alkyl group include a hydroxyl group, an amino group,
Examples thereof include a carboxyl group and an aryl group. The (meth) acrylic acid alkyl ester polymer essential to the present invention contains 50% by weight of a (meth) acrylic acid alkyl ester component.
It is a polymer containing the above, and its Tg is 0 ° C. or higher. When the Tg of the polymer is less than 0 ° C., the surface of the obtained recording medium tends to become sticky, that is, tacky, and the recording medium in such a state is easily soiled. There are practical problems. On the other hand, when the content of the (meth) acrylic acid alkyl ester component in the polymer is less than 50% by weight, the color developability of the sublimable disperse dye is lowered.

The compounding amount of the (meth) acrylic acid alkyl ester polymer is 30 with respect to 100 parts by weight of the mixture of the crosslinking agent and the polymer.
To 90 parts by weight, preferably 40 to 85 parts by weight.
The amount of the (meth) acrylic acid alkyl ester polymer is 30.
If the amount is less than 100 parts by weight, the color developability of the sublimable disperse dye is deteriorated. On the other hand, if it exceeds 90 parts by weight, the surface becomes tacky or the curing property by active energy rays is poor, and The adhesiveness to

Specific examples of the (meth) acrylic acid alkyl ester polymer include homopolymers such as methyl methacrylate, sec-butyl methacrylate, cyclohexyl methacrylate, isobutyl methacrylate, benzyl methacrylate, phenyl methacrylate and ethyl methacrylate; methyl methacrylate / styrene = 80/20. Parts by weight, methyl methacrylate / ethyl acrylate = 95
/ 5, methyl methacrylate / methyl acrylate = 9
0/10, methyl methacrylate / n-butyl methacrylate = 40/60, methyl methacrylate / ethyl methacrylate = 30/70, methyl methacrylate / ethyl acrylate = 70/30, methyl methacrylate / methyl acrylate / methacrylic acid = 60/35 /
5, methyl methacrylate / lauryl methacrylate =
90/10, methyl methacrylate / methyl acrylate / 2-hydroxyethyl methacrylate = 80/15
/ 5, methyl methacrylate / iso-butyl methacrylate / dimethylaminoethyl methacrylate = 80/1
Examples thereof include copolymers such as 5/5. These polymers may be used alone or in a mixture of two or more.

The cross-linking agent is one that can be cured with active energy rays, and as long as it has good compatibility with the (meth) acrylic acid alkyl ester polymer, any one can be used, but when the radiation source is ultraviolet rays, At least one polyfunctional monomer having a methacryloyloxy group or an acryloyloxy group as a polymerizable group, or at least 1
It is preferably composed of one such polyfunctional monomer and at least one monofunctional monomer.
The polyfunctional monomer is essential for curing the coating agent with active energy rays, but the monofunctional monomer is not essential. However, when the coating agent is applied without using a solvent, it is preferable to use a monofunctional monomer in order to reduce the viscosity of the coating agent.

As an example of the monomer having a (meth) acryloyloxy group, a polyether acrylate or polyether methacrylate type (hereinafter, "acrylate or methacrylate" is simply abbreviated as "(meth) acrylate") polyester (meth) acrylate type, polyol (Meth) acrylate-based, epoxy (meth) acrylate-based, amidourethane (meth) acrylate-based, urethane (meth) acrylate-based, spiroacetal (meth) acrylate-based and polybutadiene (meth) acrylate-based monomers and oligomers You can

Specific examples of such monomers or oligomers include 1,2,6-hexanetriol / propylene oxide / acrylic acid, trimethylolpropane / ethylene oxide / methacrylic acid, trimethylolpropane / propylene oxide / acrylic acid, pentaerythritol /
Polyether (meth) acrylate synthesized from ethylene oxide / acrylic acid; adipic acid / 1,6-hexanediol / acrylic acid, succinic acid / 1,4-butanediol / acrylic acid, succinic acid / trimethylolethane / acrylic acid , Polyester (meth) acrylate synthesized from sebacic acid / 1,6-hexanediol / methacrylic acid; ethylene glycol diacrylate, triethylene glycol diacrylate, ethylene glycol dimethacrylate, hexapropylene glycol diacrylate, neopentyl glycol di Acrylate, neopentyl glycol dimethacrylate,
1,6-hexanediol diacrylate, 1,4-butanediol methacrylate, butyl acrylate, 2
-Ethylhexyl acrylate, lauryl methacrylate, cyclohexyl acrylate, tetrahydrofurfuryl acrylate, 2-hydroxyethyl methacrylate, 1,4-butanediol monoacrylate, benzyl methacrylate, ethyl carbitol acrylate,
Trimethylol pripan triacrylate, trimethylol ethane trimethacrylate, pentaerythritol pentaacrylate, pentaerythritol trimethacrylate, dipentaerythritol tetraacrylate, dipentaerythritol pentaacrylate, dipentaerythritol hexamethacrylate, 2,2-bis (4-acrylonitrile) Roxyethoxyphenyl) propane,
2,2-bis (4-acryloxydiethoxyphenyl)
(Meth) acrylate or polyol (meth) acrylate such as propane, 2,2-bis (4-methacryloxydiethoxyphenyl) propane, 2,2-bis (4-acryloxypropoxyphenyl) propane; diglycidyl etherified bisphenol Epoxy (meth) such as A / acrylic acid, diglycidyl etherified polybisphenol A / acrylic acid, triglycidyl etherified glycerin / acrylic acid, triglycidyl etherified trimethylolethane / methacrylic acid, diglycidyl etherified aniline / acrylic acid Acrylate; γ-butyrolactone / N-methylethanolamine / bis (4-isocyanatocyclohexyl) methane / 2-hydroxyethyl acrylate, γ-butyrolactone / N-methylethanolamine / 2,6- Amido urethane (meth) acrylates such as tolylene diisocyanate / tetraethylene glycol / 2-hydroxyethyl acrylate; 2,6-
Tolylene diisocyanate diacrylate, isophorone diisocyanate diacrylate, isophorone diisocyanate dimethacrylate, urethane acrylate synthesized from hexanediol / isophorone diisocyanate / 2-hydroxyethyl acrylate, urethane acrylate such as hexamethylene diisocyanate diacrylate; dialylidene pentaerythritol / Spiro acetal acrylate synthesized from 2-hydroxyethyl acrylate; acrylated polybutadiene synthesized from epoxidized butadiene / 2-hydroxyethyl acrylate, and the like. These monomers and oligomers may be used alone or in a mixture of two or more kinds. used.

Among the monomers and oligomers, the following general formula [In the formula, n is an integer of 1 to 4, and X is at least 3 or more in the general formula: (In the formula, R ₇ represents a hydrogen atom or a methyl group, and R ₈ represents a single bond, an alkylene group having 1 to 8 carbon atoms or a polyoxyalkylene group having an alkylene group having 1 to 8 carbon atoms.) Represents a group represented by the following formula, and the remainder is an alkyl group having 1 to 8 carbon atoms, a hydroxyl group, an amino group, a formula: (In the formula, R ₉ represents an alkylene group having 1 to 8 carbon atoms, and m is a positive integer.) A group or a formula: (In the formula, R ₉ and m have the same meanings as described above.). ] It is preferable to use 30% by weight or more of the compound represented by Since the oligomers represented by these general formulas have excellent curability by irradiation with ultraviolet rays in the air, the curing property when using ultraviolet rays is improved, or the tackiness of the coating film surface is improved, When a monomer or oligomer having poor curability due to UV irradiation in air is used, curing may be slowed or the surface may become sticky. Specific examples of the compound represented by the above general formula include dipentaerythritol tetraacrylate, dipentaerythritol tetraacrylate, dipentaerythritol hexaacrylate, tripentaerythritol pentaacrylate, tripentaerythritol hexaacrylate, tripentaerythritol heptaacrylate and the like. Can be mentioned.

The compounding amount of the above-exemplified crosslinking agent is 10 to 70 parts by weight, preferably 15 to 60 parts by weight, based on 100 parts by weight of the total amount of the crosslinking agent and the (meth) acrylic acid alkyl ester polymer. When the amount of the cross-linking agent exceeds 70 parts by weight, the tack on the surface disappears, but the dyeability deteriorates, and conversely, when it is less than 10% by weight, tack occurs.

When an electron beam is used as an active energy ray, a photopolymerization initiator may not be blended, but when an ultraviolet ray having a wavelength of 100 to 800 nm is used, a photopolymerization initiator or a photosensitizer, a crosslinking agent and (meth) It is preferable to add 10.0 parts by weight or less to 100 parts by weight of the acrylic acid alkyl ester polymer mixture. Specific examples of the photopolymerization initiator include benzoin, benzoin isobutyl ether, benzyl dimethyl ketal,
Ethylphenyl glyoxylate, diethoxyacetophenone, 1,1-dichloroacetophenone, 4'-isopropyl-2-hydroxy-2-methylpropiophenone, 1-hydroxycyclohexylphenyl ketone, benzophenone, benzophenone / diethanolamine,
Carbonyl compounds such as 4,4′-bisdimethylaminobenzophenone, 2-methylthioxanthone, tert-butylanthraquinone and benzyl; sulfur compounds such as tetramethylthiuram monosulfide and tetramethylthiuram disulfide; azobisisobutyronitrile and azobis-
Azo compounds such as 2,4-dimethylvaleronitrile; peroxide compounds such as benzoyl peroxide and di-tert-butyl peroxide. These compounds are used alone or in a mixture of two or more.

The coating composition comprising the above-mentioned cross-linking agent, (meth) acrylic acid alkyl ester polymer and, if necessary, a photopolymerization initiator is roll-coated, bar-coated, or sprayed on a film-shaped or paper-shaped substrate. Coating can be performed using a coating method, a gravure coating method, a curtain coating method, a bead coating method, a flow coating method, a dip coating method, etc., but in order to improve workability, a solvent (for example, a solvent) is added to these compositions. , Ethyl alcohol, isopropyl alcohol, acetone, methyl ethyl ketone, methyl acetate,
Ethyl acetate, dimethylformamide, etc.) should be added to adjust the coating viscosity to a suitable level.

The thickness of the coating composition layer formed on the substrate surface is 0.
It is necessary to set it to 5 to 100 μm. In order to obtain a better result, the film thickness is set to 1 to 50 μm. When the film thickness becomes thinner than 0.5 μm, the dye diffusion reaches saturation on the way,
It cannot be dyed in a dark color. On the other hand, if the film thickness exceeds 100 μm, blocking tends to occur during heating.

In order to prevent the transfer of the dispersed material during the stacking of dyed films or papers, it is better to apply the composition forming the dye layer on only one side of the substrate, but this dye is actively transferred. In order to prevent dyeing, it is more preferable to provide a non-migration layer on the surface opposite to the dyeing layer.

As the composition for forming the non-migration layer, 100 parts by weight of the above-mentioned polyfunctional monomer or a monomer composed of the above-mentioned polyfunctional monomer and a monofunctional monomer, and an oligomer mixture, and if necessary, the above-mentioned photopolymerization initiator A coating agent consisting of 0.1 to 10.0 parts by weight can be used, but in order to sufficiently prevent migration by disperse dyes, the average number of polymerizable groups in the monomer / oligomer mixture is 1.5 per molecule. It is necessary to be above. Similar to the composition for forming a dyed layer, these coating agents can also be used for adjusting viscosity with a solvent, coating and curing.

The film-like or paper-like substrate used for the recording medium of the present invention may be any one as long as it is generally used as a substrate for dry transfer. Specific examples of the film / paper include polyester films, propylene films, nylon films, vinyl chloride films, and other film-like materials; wood-based art paper, acrylic fiber-based acrylic paper, polyester paper, etc. Paper-like materials are mentioned, and polyester film or acrylic paper or art paper is particularly preferable in consideration of heat resistance, and polyester film is most preferable in consideration of transparency of the article.

These papers or films may be used as they are, or if necessary, those that have been subjected to pretreatments such as washing, etching, corona discharge, active energy ray irradiation, dyeing and printing. Good.

In the recording medium of the present invention, first, the above-mentioned coating composition is usually uniformly mixed in advance and applied to the surface of paper or film.

Next, the coating film on the paper or film is cured by active energy rays.

As the active energy rays, ultraviolet rays emitted from a radiation source such as a xenon lamp, a low-pressure mercury lamp, a high-pressure mercury lamp or an ultra-high-pressure mercury lamp, an electron beam normally extracted from an electron beam accelerator of 20 to 2000 kV, an α ray, a β ray, a γ ray, etc. And the like. Considering handling and workability, ultraviolet rays having a wavelength of 100 to 800 nm are preferable.

[Advantages of the Invention] The disperse dye dry transfer color-recording recording medium of the present invention is easily dyed with a sublimable disperse dye, and is significantly superior in color developability and vividness to conventional ones. It has high heat resistance and can perform dry transfer of disperse dyes at low temperature in a short time. Therefore, the recording medium according to the present invention is extremely useful as a material for dry transfer coloring for color copying, electrophotography, or information recording, and its industrial value is great.

Example of Invention

Hereinafter, examples of the present invention will be described in more detail. In the examples and comparative examples, all "parts" represent parts by weight.

Reference Example 1 Preparation of Transfer Sheet: A commercially available transfer paper was uniformly coated with a 5% trichlorethylene solution of Kayaset Blue 136 (Nippon Kayaku) to prepare a transfer sheet.

Reference Example 2 Dry transfer recording method: Using a fusing press XVOB 6.5 / 14 type (manufactured by Carnegicer), the transfer sheet of Reference Example 1 was placed on the surface of the dyeing layer of the recording material for dry transfer color development, and the contact pressure was 2 kg / cm ^2. , Temperature 15
Dry transfer printing was carried out at 0 ° C. for 10 seconds.

Reference Example 3 Surface Tackiness Evaluation Method: The surface of the dyeing layer of the recording material for color development of the dry transfer recording agent was brought into contact with the surface, and those having tackiness or tackiness on the surface were evaluated as tacky, and those without were evaluated as tack-free.

Reference Example 4 Dyeing Density Measuring Method: The dyeing density was determined as −logT by measuring the light transmittance T using a color analyzer (Hitachi, Model 307).

Example 1, Comparative Examples 1 to 4 The coating compositions shown in Table I were mixed and prepared, and then uniformly coated on a 100 μm-thick polyester film by a dipping method. When this was irradiated with ultraviolet rays in the air, a disperse dye dry transfer recording material for recording having a dyeing layer having a film thickness of 5 μm was obtained.

When evaluation tests were performed on these recording media according to Reference Examples 1 to 4, the results shown in Table I were obtained.

Examples 2 to 3 and Comparative Examples 5 to 8 The coating composition shown in Table II was uniformly applied on a 100 μm polyester film subjected to corona discharge treatment by a dipping method. When these are irradiated with ultraviolet rays in the air, the film thickness is 4
A disperse dye dry transfer recording material having a dye layer of μm was obtained.

Table II shows the results of evaluation tests performed on these recording media according to Reference Examples 1 to 4.

Example 4 Composition comprising 10 parts of dipentaerythritol hexaacrylate, 20 parts of dipentaerythritol pentaacrylate, 10 parts of dipentaerythritol tetraacrylate, 40 parts of tetrahydrofurfuryl acrylate, 6 parts of 2-hydroxy-2-methylpropiophenone 1
After coating with a roll coater on one side of a 00 μm polyester film, the film is exposed to ultraviolet rays in the air to give a film thickness of 7
A non-transferred layer of μm was provided.

An oligomer synthesized from 5 parts of dipentaerythritol hexaacrylate, 5 parts of dipentaerythritol pentaacrylate, 5 parts of dipentaerythritol tetraacrylate, and succinic acid / trimethylolethane / acrylic acid on the side opposite to the non-migration layer of this film. A composition comprising 25 parts, acrylic polymer A 60 parts (butyl methacrylate / methyl methacrylate = 60/40, Tg 50 ° C.), methyl ethyl ketone 150 parts, DMF 50 parts, and benzyl dimethyl ketal 6 parts was applied by a roll coater, and then ultraviolet light was applied in the air. Was irradiated to form a dyed layer having a thickness of 4 μm.

An evaluation test was performed on the obtained dyed layer of the recording medium according to Reference Examples 1 to 4, and the dyeing density was -logT =
The surface tackiness was 0.55, and the tackiness was good.

Even when 10 dyed articles were stacked and a 2 kg weight was placed thereon and left for 3 months, almost no migration of the dye to the non-transferred layer was observed.

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Claims (7)

[Claims] 1. A surface of a substrate comprising 10 to 70 parts by weight of a crosslinking agent curable with active energy rays and at least one kind of (meth) acrylic acid alkyl ester polymer,
50% by weight of (meth) acrylic acid alkyl ester component
A coating film of a coating composition containing 90 to 30 parts by weight of a polymer having the glass transition point Tg of 0 ° C. or higher (selected so that the sum of the two is 100 parts by weight) is irradiated with active energy rays. Cured film thickness 0.5-10
A sublimation-type disperse dye thermal transfer recording system recording medium having a cured film of 0 μm. 2. The cross-linking agent is at least one which is UV curable.
The recording medium according to claim 1, which is a multifunctional monomer of a kind. 3. The recording medium according to claim 2, wherein the polyfunctional monomer contains a polymerizable (meth) acryloyloxy group. 4. The active energy ray has a wavelength of 100 to 80.
The recording medium according to any one of claims 1 to 3, which is ultraviolet light having a wavelength of 0 nm. 5. The recording medium according to any one of claims 1 to 4, wherein the substrate is a plastic film. 6. The recording medium according to any one of claims 1 to 4, wherein the substrate is acrylic paper mainly containing acrylic fibers or art paper mainly containing wood fibers. . 7. A cross-linking agent 10 curable with active energy rays.
To 70 parts by weight, at least one kind of (meth) acrylic acid alkyl ester polymer, containing 50% by weight or more of a (meth) acrylic acid alkyl ester component, and its Tg.
Coating composition consisting of 90 to 30 parts by weight of a polymer having a temperature of 0 ° C. or higher (chosen so that the sum of the two is 100 parts by weight) and a photopolymerization initiator is applied to one side of a substrate, and an active energy ray is applied. Film thickness of 0.5 by irradiation and curing
A method for producing a recording medium of a sublimation type disperse dye thermal transfer recording system, which comprises forming a cured film having a thickness of about 100 μm.