JPH10338813A - Resin composition and image receptor for thermal transfer recording - Google Patents

Abstract

PROBLEM TO BE SOLVED: To form a high-color-density clear recording image by using the dye reception layer of an image receptor for thermal transfer recording. SOLUTION: The dye reception layer is formed by using an aqueous emulsion consisting of an emulsion containing polymer particles having a crosslinkage or crosslinkable polymer particles. The polymer particles are made of a copolymer of a polyfunctional monomer having at least two polymerizable unsaturations in the molecule with a monofunctional vinyl monomer, a copolymer of a crosslinking monomer with a monofunctional vinyl monomer or a copolymer of a polyfunctional monomer having at least two polymerizable unsaturations in the molecule with a crosslinking monomer and a monofunctional vinyl monomer. The polymer particles can be made from a monomer mixture containing a (meth)acrylic monomer and an aromatic vinyl monomer (e.g. styrene).

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a resin composition for thermal transfer recording which is useful for forming a clear recorded image on a dye receiving layer by thermal transfer, an image receiving body for thermal transfer recording using the resin composition, and the same. It relates to a manufacturing method.

[0002]

2. Description of the Related Art As a thermal transfer method, various methods have conventionally been used.
For example, a thermal transfer sheet in which a recording material such as a sublimable dye is carried on a base sheet (eg, a polyester film), and a dye receiving member capable of dyeing a material to be transferred (eg, paper or a plastic film) with a sublimable dye. There has been proposed a method in which a full-color image is formed on an image receiving sheet by heating by bringing the layer into contact with an image receiving sheet having a layer formed thereon.
In this method, a thermal head of a printer is used as a heating means, and three colors or four colors can be obtained by heating for a very short time.
A large number of color dots are transferred to an image receiving sheet to reproduce a full-color image corresponding to the original. The image formed in this manner is very clear because the coloring material is a dye, and is excellent in transparency, so that the obtained image has excellent intermediate color reproducibility and gradation, and is a full-color photographic image. It is possible to form a high quality image comparable to the above.

In the thermal transfer method, not only the configuration of the thermal transfer sheet but also the configuration of an image receiving sheet for forming an image is important. As the thermal transfer recording image receiving sheet, for example, polyester resin, halogen-containing vinyl resin such as polyvinyl chloride resin, polycarbonate resin, polyvinyl butyral resin, acrylic resin, cellulose resin, olefin resin, styrene resin, etc. A sheet having a dye receiving layer formed thereon is known. In such a thermal transfer recording image-receiving sheet, a dye-receiving layer is formed using a resin having good dyeability in order to improve the dyeability of the sublimable dye to be transferred. JP-A-62-211195 proposes an image-receiving sheet for thermal transfer recording, in which an image-receiving layer having a high surface smoothness is formed from a mixture containing an easily dyeable resin such as polyester and polystyrene and a pigment. This document describes that the easily dyeable resin may be of an emulsion type. JP-A-62-189195
Japanese Patent Application Laid-Open Publication No. H11-209,086 discloses a heat transfer sheet in which an image receiving layer carried on a substrate is formed of a styrene resin. This document also describes forming a release agent layer on the surface of the image receiving layer. However, a resin having a high dye-dyeing property has a low softening point. When the dye-receiving layer of the thermal transfer recording image-receiving sheet is formed of such a resin, the heat of the thermal head during image formation causes the dye-receiving layer and the thermal transfer sheet to be in contact with each other. Are fused, and a loud peeling sound is generated at the time of peeling, or a problem that the dye layer of the thermal transfer sheet is transferred to the image receiving sheet (so-called abnormal transfer) occurs.

Japanese Patent Application Laid-Open No. 62-222895 discloses that a dyeing layer of a sublimation type thermal recording image receiver contains an acrylic polymer and a surface modifier having a fluorine or silicone graft or block structure. Is disclosed. JP-A-2-81674 discloses that a sublimable dye-receiving layer comprises a resin (for example, a main dye such as polyester, vinyl chloride resin, acrylic resin and nylon resin) which is easily dyed, and a room temperature curing. There is disclosed an image receiving medium composed of an acrylic urethane silicone resin (a mold release aid) and containing an acrylic urethane silicone resin at least in a surface layer portion. JP-A-6-24152 discloses that
It has been proposed to form a dye-receiving layer of a sublimation transfer recording image receiver with a composite polymer aqueous dispersion in which a core-shell structure is formed by a polymer of a polyester resin having at least one polar group and a polymerizable unsaturated compound. ing.
These image receivers have high releasability from the thermal transfer sheet, but it is difficult to improve the color density and sharpness while maintaining the releasability at a high level. In addition, room temperature curing type acrylic urethane silicone resin cures at room temperature,
Decrease handling. As described above, when the dyeing property of the dye is improved, the releasability is reduced. When the releasability is improved, the dyeing property of the dye is reduced, and a high-density and high-clarity image cannot be formed. .

[0005]

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a resin composition for thermal transfer recording which has a high releasability (release property) from a thermal transfer sheet and can form a recorded image excellent in color density and sharpness. Another object of the present invention is to provide a thermal transfer recording image receiving body using the resin composition and a method for producing the same.
Another object of the present invention is to provide a thermal transfer method using a sublimable dye, which is excellent in releasability (release property) from a thermal transfer sheet in an image forming process or thermal transfer and is capable of forming a high quality recorded image. An object of the present invention is to provide a resin composition, an image receiving body for thermal transfer recording using the resin composition, and a method for producing the same.

[0006]

Means for Solving the Problems As a result of intensive studies to achieve the above object, the present inventors have found that the dye receiving layer of the thermal transfer recording image receiving member is formed by polymer particles having a crosslinked structure or crosslinkable polymer. It has been found that the formation of an emulsion containing coalesced particles can maintain a high level of releasability from a thermal transfer sheet during thermal transfer, and can form a recorded image with high color density and excellent sharpness, thus completing the present invention. That is,
The resin composition of the present invention is used for forming a dye-receiving layer of a thermal transfer recording image receptor, and is composed of (1) a polymer particle having a crosslinked structure or (2) an emulsion containing a crosslinkable polymer particle. ing. The polymer particles (1) and (2)
Advantageously, it is formed from a monomer containing at least an aromatic vinyl monomer. The polymer particles include a copolymer of a polyfunctional monomer having at least two polymerizable unsaturated bonds in the molecule and a monofunctional vinyl monomer, a crosslinkable monomer and a monofunctional vinyl monomer. Copolymer with a polyfunctional monomer, or a copolymer of a polyfunctional monomer having at least two polymerizable unsaturated bonds in the molecule, a crosslinkable monomer, and a monofunctional vinyl monomer Can be configured. The present invention also includes a thermal transfer recording image receiver in which the dye receiving layer is composed of the resin composition. The present invention also includes a method for producing a thermal transfer recording image-receiving body, in which the resin composition is applied to at least one surface of a substrate to form a dye-receiving layer. In the present specification, the sublimable dye refers to a dye that sublimates by heat. The “thermal transfer recording image receiver” may be simply referred to as “image receiver”, and the “dye receiving layer” may be simply referred to as “receiving layer”. “Acrylic” monomers and “methacrylic” monomers are collectively referred to as “(meth) acrylic” monomers.

[0007]

BEST MODE FOR CARRYING OUT THE INVENTION The emulsion constituting the resin composition of the present invention includes (1) an emulsion containing polymer particles having a crosslinked structure, and (2) a crosslinkable polymer particle (ie,
Emulsions containing polymer particles crosslinkable by a crosslinking system). Also, emulsions
The combination of the above (1) and (2), that is, an emulsion containing a crosslinkable polymer particle having a crosslinked structure is also included. A feature of these emulsions is that a crosslinked structure is formed by film formation, and the heat resistance and the releasability from the thermal transfer sheet can be greatly improved.

[Polymer Particles Having Cross-Linked Structure] In the polymer particles having a cross-linked structure, the cross-linked structure may be caused by various cross-linking systems, for example, metal cross-linking, cross-linking by a cross-linking agent, and the like. A preferred crosslinked structure is a polyfunctional monomer having at least two polymerizable unsaturated bonds in a molecule, and a monofunctional vinyl monomer copolymerizable with the polyfunctional monomer. It can be formed by copolymerization.

[0009] As the polyfunctional monomer, 2 to 4
Monomers containing about one polymerizable unsaturated bond, for example, divinylbenzene, diallyl ether, alkylene glycol di (meth) acrylate [ethylene glycol di (meth) acrylate, propylene glycol di (meth) acrylate, butanediol di ( Meth) acrylates,
Hexanediol di (meth) acrylate, neopentyl glycol di (meth) acrylate, etc.], (poly)
Oxyalkylene glycol di (meth) acrylate [diethylene glycol di (meth) acrylate, triethylene glycol di (meth) acrylate, polyethylene glycol di (meth) acrylate, dipropylene glycol di (meth) acrylate, tripropylene glycol di (meth) acrylate , Polypropylene glycol di (meth) acrylate, polyoxytetramethylene glycol di (meth) acrylate, etc.], glycerin di (meth) acrylate, glycerin tri (meth)
Examples thereof include acrylate, trimethylolpropane tri (meth) acrylate, pentaerythritol tri (meth) acrylate, and pentaerythritol tetra (meth) acrylate. These polyfunctional monomers can be used alone or in combination of two or more. As the polyfunctional monomer, divinylbenzene, alkylene glycol di (meth) acrylate, (poly) oxyalkylene glycol di (meth) acrylate and the like are usually used.

The amount of the polyfunctional monomer used is within a range that does not impair the film-forming properties and can effectively introduce a crosslinked structure, for example, 0.1 to 20% by weight based on the whole monomer, preferably Can be selected from a range of about 0.5 to 10% by weight, more preferably about 1 to 5% by weight, and is usually about 1 to 10% by weight.

The monofunctional vinyl monomers include non-crosslinkable copolymerizable monomers such as (meth) acrylic monomers, vinyl ester monomers, aromatic vinyls and halogen-containing monomers. Vinyls, vinyl ethers (eg, vinyl ethyl ether, vinyl isobutyl ether, etc.), vinyl ketones (eg, methyl vinyl ketone, etc.), vinyl heterocyclic compounds (eg, N-vinyl pyrrolidone, N-
N-vinyl compounds such as vinylimidazole, vinylpyridine, etc., olefinic monomers (eg, ethylene, propylene, etc.), allyl compounds (eg, allyl esters such as allyl alcohol, allyl ether, allyl acetate, etc.) are included. It is. Monofunctional vinyl monomers can be used alone or in combination of two or more.

(Meth) acrylic monomers include, for example,
(Meth) acrylates, (meth) acrylamides,
(Meth) acrylonitrile and the like are included. (Meth) acrylate includes, for example, alkyl (meth) acrylate [for example, methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, isopropyl (meth) acrylate, butyl (meth) acrylate, isobutyl (meth) acrylate. ) Acrylate, t-butyl (meth) acrylate, hexyl (meth) acrylate, octyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, _C1-18 alkyl (meth) acrylate such as lauryl (meth) acrylate, etc.),
Cycloalkyl (meth) acrylates [eg, cyclohexyl (meth) acrylate, etc.], aryl (meth) acrylates [eg, phenyl (meth) acrylate, etc.], aralkyl (meth) acrylates [eg, benzyl (meth) acrylate, etc.], etc. included. (Meth) acrylamides include, for example, (meth)
Acrylamide, diacetone (meth) acrylamide and the like are included. Preferred (meth) acrylic monomers include, for example, C _2-10 alkyl acrylate, C _1-6 alkyl methacrylate, acrylamide, and acrylonitrile.

The aromatic vinyls include, for example, styrene,
α-methylstyrene, α-halostyrene, alkyl-substituted styrenes (vinyltoluene, p-ethylstyrene, etc.), halogen-substituted styrenes (chlorostyrene, etc.)
And so on. Preferred aromatic vinyls include styrene, α-methylstyrene, vinyltoluene (especially styrene). Vinyl ester monomers include, for example, vinyl acetate, vinyl propionate, vinyl versatate (VeoVa and the like), and the like. Halogen-containing vinyls include, for example, vinyl chloride, vinylidene chloride, and the like.

Preferred non-reactive vinyl monomers (monofunctional vinyl monomers) include (meth) acrylic monomers (such as (meth) acrylate) and aromatic vinyls (styrene ), Vinyl esters (eg, vinyl acetate), and halogen-containing vinyls (eg, vinyl chloride). Especially,
(Meth) acrylic monomers and aromatic vinyls are preferred.

The crosslinkable polymer particles are not limited to copolymers of the above-mentioned polyfunctional monomers and monofunctional vinyl monomers, and may be formed of a copolymer of the above-mentioned functional vinyl monomers. It may be a copolymer.

[Crosslinkable Polymer Particles] The crosslinkable polymerizable particles (2) are composed of a monomer having various crosslinkable groups (crosslinkable monomer) and a copolymerizable vinyl monomer (the monofunctional monomer described above). (A vinyl-based monomer). Examples of the crosslinkable monomer include a hydroxyl group-containing monomer, a carboxyl group-containing monomer, a glycidyl group or an epoxy group-containing monomer, an amino group or a derivative thereof-containing monomer, and a hydrolyzable silyl group. Contained monomers and the like.

Among the crosslinkable monomers, examples of the carboxyl group-containing monomer include unsaturated carboxylic acids such as unsaturated monocarboxylic acids [eg, ethylenically unsaturated monocarboxylic acids such as (meth) acrylic acid and crotonic acid. Acid or the like], unsaturated polycarboxylic acid [eg, ethylenically unsaturated polycarboxylic acid such as maleic acid, fumaric acid, itaconic acid and the like, and acid anhydrides (such as maleic anhydride) or esters thereof (eg, maleic acid) Monomethyl esters of dicarboxylic acids such as monomethyl and monobutyl maleate)
Etc.] are included. Preferred unsaturated carboxylic acids include, for example, monocarboxylic acids such as (meth) acrylic acid, polycarboxylic acids such as maleic acid, and acid anhydrides or esters thereof.

The hydroxyl group-containing monomer includes, for example,
Hydroxyalkyl (meth) acrylate [for example, 2
-Hydroxyethyl, 2-hydroxypropyl (meth)
Can hydroxy -C _2-4 alkyl (meth) acrylate, etc.] are exemplified such as acrylate, the glycidyl group-containing monomer, glycidyl (meth) acrylate, and allyl glycidyl ether.

As a monomer containing an amino group or a derivative thereof,
Is, for example, dialkylamino-alkyl (meth)
Relevant [for example, 2- (dimethylamino) ethyl (meth
Acrylate), 2- (diethylamino) ethyl (meth)
TA) Di-C such as acrylate _1-4Alkylamino-C
_2-4Alkyl (meth) acrylate, etc.], hydroxy
Alkyl (meth) acrylamide [for example, N-methylo
N-hydroxy-C such as phenol (meth) acrylamide
_1-4Alkyl (meth) acrylamide, etc.], alkoxy
Sialkyl (meth) acrylamide [for example, N-meth
NC such as xymethyl (meth) acrylamide_1-4A
Lucoxy-C_1-4Alkyl (meth) acrylamide
Etc.] are included. Monomers with hydrolyzable silyl groups
Is a (meth) acrylic monomer, vinyl group or alkenyl
And a monomer having a group. Hydrolyzable silyl group
As the (meth) acrylic monomer having
2- (meth) acryloxyethyltrichlorosilane, 3
-(Meth) acryloxypropyltrichlorosilane, 2
-(Meth) acryloxyethylmethyldichlorosilane,
2- (meth) acryloxyethyldimethylchlorosila
, 2- (meth) acryloxyethyltrimethoxysila
, 2- (meth) acryloxyethyltriethoxysila
, 3- (meth) acryloxypropyl trimethoxy
Orchid, 3- (meth) acryloxypropyltriethoxy
Silane, 3- (meth) acryloxypropyl tris (2
-Methoxyethoxy) silane and the like.

Examples of the monomer having a hydrolyzable silyl group and a vinyl or alkenyl group include vinyltrichlorosilane, vinylmethyldichlorosilane, isopropenyltrichlorosilane, and isopropenyldimethylchlorosilane; vinyltrimethoxysilane, vinyl Triethoxysilane, vinyldimethoxymethylsilane, vinyldiethoxymethylsilane, isopropenyltrimethoxysilane, isopropenyltriethoxysilane, vinyltris (2-methoxyethoxy) silane, etc .; allyltrichlorosilane, allylmethyldichlorosilane, etc .; allyltrimethoxy Silane, vinylphenyltrimethoxysilane, isopropenylphenyltrimethoxysilane and the like;
3- [2- (allyloxycarbonyl) phenylcarbonyloxy] propyltrimethoxysilane, 3- [2-
(Isopropenylmethyloxycarbonyl) phenylcarbonyloxy] propyltrimethoxysilane and the like; 3
-(Vinylphenylamino) propyltrimethoxysilane, 3- (vinylphenylamino) propyltriethoxysilane and the like; 3- [2- (N-vinylphenylmethylamino) ethylamino] propyltrimethoxysilane,
3- [2- (N-isopropenylphenylmethylamino) ethylamino] propyltriethoxysilane and the like;
2- (vinyloxy) ethyltrimethoxysilane, 3-
(Vinyloxy) propyltrimethoxysilane, 4-
(Vinyloxy) butyltriethoxysilane, 2- (isopropenyloxy) ethyltrimethoxysilane and the like;
3- (allyloxy) propyltrimethoxysilane, 1
0- (allyloxycarbonyl) decyltrimethoxysilane, 3- (isopropenylmethoxy) propyltrimethoxysilane and the like; 3-[(meth) acryloxyethoxy] propyltrimethoxysilane, 3-[(meth) acryloxyethoxy] Propyldimethoxymethylsilane, etc.]; divinyldimethoxysilane, divinyldiethoxysilane, divinyldi (β-methoxyethoxy) silane and the like.

These crosslinkable monomers can be selected according to the type of the crosslinking system. Preferred crosslinking systems using a crosslinking monomer include (a) a crosslinking system using a combination of a carboxyl group-containing monomer and a glycidyl group-containing monomer, and (b) a crosslinking system using an N-methylol group-containing monomer. (C) a crosslinking system using a hydrolyzable silyl group-containing monomer, (d) a crosslinking system using a combination of a hydroxyl group-containing monomer or a carboxyl group-containing monomer and a hydrolyzable silyl group-containing monomer. Or a combination thereof (for example, a combination of a crosslinking system (a) and a crosslinking system (c), etc.). In particular, the crosslinking system according to the above (a) or (d) is preferable.

The amount of the crosslinkable monomer used (the total amount of the crosslinkable monomer when a crosslinkable monomer is composed of a plurality of crosslinkable monomers) depends on the type of the crosslinkable monomer and the type of the crosslinkable system. Accordingly, a range in which crosslinking can be imparted, for example, 0.1 to 30% by weight, preferably 0.5 to 25% by weight, more preferably 1 to 20% by weight (e.g.
0% by weight).

More specifically, the crosslinkable polymer particles are composed of a copolymer of a vinyl monomer having a glycidyl group, a vinyl monomer having a carboxyl group, and a copolymerizable vinyl monomer. In such a case, the content of the vinyl monomer having a glycidyl group is 0.1 to 30% by weight (preferably 0.5 to 25% by weight, more preferably 1 to 20% by weight, About 1 to 10% by weight), and the content of the vinyl monomer having a carboxyl group is 0.1 to 1%.
It is about 0% by weight (preferably 0.5 to 8% by weight, more preferably 1 to 5% by weight).

Incidentally, in the crosslinkable polymer particles (2),
As the copolymerizable vinyl monomer, the non-reactive vinyl monomer (monofunctional vinyl monomer) exemplified in the section of the polymer particles (1) having a crosslinked structure can be used.

In thermal transfer recording, in order to enhance the color density and sharpness of an image, the polymer particles (1) and the crosslinkable polymer particles (2) having a crosslinked structure must have at least an aromatic vinyl monomer. Advantageously, it is formed from monomers containing the body. The aromatic vinyl monomer includes, in addition to the aromatic vinyl monomer (styrene and the like), a (meth) acrylic monomer having an aromatic ring (phenyl (meth) acrylate and the like), And a monomer having a hydrolyzable silyl group having a sex ring. The amount of the aromatic vinyl monomer to be used is, for example, 5 to 90% by weight, preferably 10 to 80% by weight, more preferably 2 to 90% by weight, based on all monomers.
It can be selected from a range of about 5 to 70% by weight (for example, 25 to 60% by weight).

The resin composition of the present invention comprises an emulsion containing polymer particles (1) having a crosslinked structure, an emulsion containing crosslinkable polymer particles (2) alone, or a polymer particle having a crosslinked structure (1). ) And cross-linked polymer particles (2). further,
The polymer particles (3) may have a crosslinked structure and be crosslinkable by using a polyfunctional monomer and a crosslinkable monomer. The polymer particles (1) to (3) can be obtained by a conventional emulsion polymerization method.

The emulsion polymerization may be a seed polymerization using polymer particles as seeds. In the emulsion polymerization, the monomer may be used as a pre-emulsified emulsion. Further, the monomer may be charged into the reaction system at a time and polymerized, or a part of the monomer may be charged and the remaining portion may be added for polymerization. The monomer may be continuously added to the emulsion polymerization system by dropping or the like, or may be added intermittently. In the emulsion polymerization, a method combining these methods may be employed. In the emulsion polymerization, a conventional method such as a multi-stage polymerization method can be employed. Multi-stage polymerization, for example, at least in the presence of polymer particles, continuously or intermittently,
Emulsion polymerization can be carried out by adding monomers in multiple stages. In this method, the composition of the monomer to be added is
It may be different in the emulsion polymerization step (for example, the initial stage and the late stage). For example, the proportion of the crosslinkable monomer may be increased at a later stage than at the beginning.

The emulsion polymerization can be carried out using a polymerization initiator, for example, a water-soluble polymerization initiator such as potassium persulfate, sodium persulfate, ammonium persulfate or the like, or hydrogen peroxide. May constitute a water-soluble resin-type polymerization initiator system. Further, in order to adjust the molecular weight of the polymer, a chain transfer agent, for example, an alcohol such as catechol, a thiol, or a mercaptan may be used. The polymerization temperature can be generally selected from the range of about 30 to 100 ° C., depending on the type of the polymerization initiator.

The polymer particles of the emulsion obtained by emulsion polymerization may have a homogenous structure or a hetero-phase structure (for example, a core-shell structure or a micro-domain structure). The average particle size of the polymer particles is dispersion stability,
A range that does not impair the adhesiveness, for example, 0.01 to 5 μm
m (for example, 0.01 to 1 μm), preferably 0.01
To 2 μm, more preferably 0.01 to 1 μm.

In the emulsion polymerization, for example, anionic surfactants (eg, sodium dodecylbenzenesulfonate, sodium alkyldiphenyletherdisulfonate, sodium alkylnaphthalenesulfonate, sodium lauryl sulfate, sodium polyoxyethylene alkyl ether sulfate, polyoxyethylene Sodium ethylene alkyl phenyl ether sulfate, sodium dialkyl sulfosuccinate), nonionic surfactants (eg, polyoxyethylene lauryl ether, polyoxyethylene oleyl phenyl ether, polyoxyethylene nonyl phenyl ether, oxyethylene / oxypropylene block copolymer) ) And protective colloids such as polyvinyl alcohol and water-soluble polymers can be used. The amount of the emulsifier used is, for example, 0.1 to 10% by weight, preferably 0.1 to 10% by weight based on the total amount of the monomers.
5-8% by weight. More preferably, it is about 1 to 8% by weight.

The pH of the emulsion may be adjusted. The pH of the emulsion is, for example, 5 or more (for example,
5 to 10), preferably about 6 to 9 in a neutral to weakly alkaline region. Although the glass transition temperature of the polymer particles having a crosslinked structure may not be clear, the glass transition temperature (Tg) of the polymer particles is, for example, −20 ° C. to 50 ° C.
° C, preferably about -10 ° C to 40 ° C. The minimum film formation temperature (MFT) of the aqueous emulsion is, for example,
The temperature is 0 to 40 ° C, preferably about 0 to 35 ° C.

[0032] The resin composition of the present invention may be prepared from various other aqueous resins, for example, non-crosslinkable vinyl polymers such as other non-crosslinkable acrylic resins, urethane resins, polyester resins, polyamide resins, and the like. It may contain an epoxy resin or the like. The resin composition, in order to improve the releasability at the time of thermal transfer and weather resistance of the recorded image, for example, a fluororesin,
Lubricant such as silicone resin, organic sulfonate compound, organic phosphate compound, organic carboxylate compound, stabilizer such as antioxidant, ultraviolet absorber, heat stabilizer, radical scavenger, quencher, electrification Additives such as inhibitors, plasticizers, thickeners and defoamers may be added.

Since the resin composition of the present invention has a polymer particle having a crosslinked structure or is crosslinkable, when applied to a receptor layer of an image receiving member, it has excellent releasability at the time of thermal transfer and can smoothly produce high quality images. Can be formed. Further, it is possible to form a high-quality image having high color density and excellent sharpness.

[Receiver for Thermal Transfer Recording] As the base material of the receiver, for example, natural paper, synthetic paper (for example, polypropylene-based, polystyrene-based, polyester-based synthetic paper, etc.),
A plastic film (for example, a polyester film such as polyalkylene terephthalate (eg, polyethylene terephthalate, polybutylene terephthalate), an olefin-based film such as polypropylene, a polyamide film such as nylon, or a laminate thereof) can be used. Preferred substrates include heat-resistant substrates, such as synthetic paper, plastic films. The thickness of the substrate is, for example, 5 to 500, depending on the application.
μm, preferably from 10 to 300 μm, more preferably from about 50 to 200 μm. If necessary, additives such as antioxidants, ultraviolet absorbers, stabilizers such as heat stabilizers, lubricants, antistatic agents, fillers, and pigments may be added to the base material.

The image receiving body of the present invention has a receiving layer composed of the resin composition on at least one surface of the substrate. This receiving layer can be formed by applying a coating solution containing a resin composition to a base material and drying the coating solution. This coating solution is
The resin composition can be prepared using an appropriate solvent (for example, water, an aqueous or non-aqueous organic solvent, or a mixed solvent thereof). When the resin composition is an aqueous emulsion, the coating solution is aqueous. As a method for applying the coating solution, a conventional method, for example, a roll coating method such as gravure or reverse, a doctor knife method, a knife coating method, a nozzle coating method, and the like can be adopted.

The layer structure of the receiving layer of the image receiving body may be a single layer or a plurality of layers, and is usually a single layer. The thickness of the receiving layer is, for example, 0.1 μm
(For example, 0.1 to 50 μm), preferably 0.5
μm or more (for example, 0.5 to 40 μm), and more preferably a range of about 1 to 30 μm.

The image receiver of the present invention is used in combination with a thermal transfer sheet containing a sublimable dye. The image receiving body of the present invention is a thermal transfer method, for example, by contacting the dye receiving layer of the image receiving body with a thermal transfer sheet containing a sublimable dye, and heating using a thermal head or the like to receive the dye of the thermal transfer sheet. It is useful for transferring to a body and forming an image on a receiver.

[0038]

The resin composition of the present invention is composed of an emulsion containing polymer particles having a cross-linked structure or cross-linkable polymer particles. A high-quality image with excellent clarity can be formed. In particular, releasability from the thermal transfer sheet during the image forming process or thermal transfer is high. Therefore, a high quality image can be formed while maintaining the releasability from the thermal transfer sheet at a high level.

[0039]

The present invention will be described below in more detail with reference to Examples, but the present invention is not limited to these Examples. Example 1 A reaction vessel equipped with a stirrer, a reflux condenser, a nitrogen gas inlet pipe and a thermometer was charged with 200 g of ion-exchanged water and 1 g of a surfactant (trade name: Emulgen 935, manufactured by Kao Corporation) and stirred. While heating to 80 ° C. An emulsion obtained by emulsifying in advance 4 g of a monomer A having the following composition, a surfactant (trade name: Emulgen 935, manufactured by Kao Corporation) and 70 g of ion-exchanged water, and a catalyst aqueous solution (0.75 g of potassium persulfate and ion-exchanged water) 24.25 g of an aqueous solution) was dropped into the reaction vessel over 3 hours. [Composition of Monomer A] 30 g of methyl methacrylate, 55 butyl acrylate
g, styrene 110 g, divinylbenzene 5 g. After completion of the dropwise addition, the mixture was further reacted for 1 hour, and then cooled to room temperature.
The pH was adjusted by adding ammonia water, and the aqueous emulsion (solid content concentration 38% by weight, pH 7.1, viscosity 10 cp)
s (30 ° C)).

Example 2 A monomer B having the following composition was used in place of the monomer A,
Aqueous emulsion (solid content concentration 36% by weight, pH 7.1, viscosity 12 cps (30 ° C.)) in the same manner as in Example 1.
I got [Composition of Monomer B] 30 g of methyl methacrylate, 55 butyl acrylate
g, styrene 105 g, divinylbenzene 10 g.

Example 3 A monomer C having the following composition was used instead of the monomer A,
Aqueous emulsion (solid content 40% by weight, pH 7.0, viscosity 15 cps (30 ° C.)) in the same manner as in Example 1.
I got [Composition of Monomer C] 30 g of methyl methacrylate, 55 butyl acrylate
g, styrene 110 g, diethylene glycol diacrylate 5 g.

Example 4 A monomer D having the following composition was used in place of the monomer A,
Aqueous emulsion (solid content 40% by weight, pH 7.2, viscosity 17 cps (30 ° C.)) in the same manner as in Example 1.
I got [Composition of Monomer D] Methyl methacrylate 21 g, butyl acrylate 55
g, styrene 110 g, acrylic acid 3 g, glycidyl methacrylate 6 g.

Example 5 A monomer E having the following composition was used in place of the monomer A,
Aqueous emulsion (solid content 39% by weight, pH 7.0, viscosity 15 cps (30 ° C.)) in the same manner as in Example 1.
I got [Composition of Monomer E] Methyl methacrylate 18 g, butyl acrylate 55
g, styrene 110 g, 2-hydroxyethyl methacrylate 6 g, 3-methacryloxypropyltrimethoxysilane 6 g.

Comparative Example 1 A monomer F having the following composition was used in place of the monomer A,
Aqueous emulsion (solid content 39% by weight, pH 7.2, viscosity 10 cps (30 ° C.)) in the same manner as in Example 1.
I got [Composition of Monomer F] 30 g of methyl methacrylate, 55 butyl acrylate
g, 115 g of styrene.

Comparative Example 2 A monomer G having the following composition was used instead of the monomer A,
Aqueous emulsion (solid concentration 40% by weight, pH 7.1, viscosity 17 cps (30 ° C.)) in the same manner as in Example 1.
I got [Composition of Monomer G] Methyl methacrylate 27 g, butyl acrylate 55
g, styrene 110 g, acrylic acid 3 g.

(Preparation of Thermal Transfer Recording Image Receiver) The emulsions of the above Examples and Comparative Examples were prepared by mixing 150 μm thick polypropylene synthetic paper (Yupo FPG- manufactured by Oji Oil Chemicals, Inc.).
150) was applied using a wire bar so as to obtain a dry coating film of 10 μm, and dried at 110 ° C. for 10 minutes to obtain a thermal transfer recording image receiver having a dye receiving layer.

(Evaluation of Printed Image Density) A sublimation type digital color printer DPP-M1 was mounted on an image receiving body (image receiving sheet).
The image was printed using (manufactured by Sony Corporation) and the color density was measured with a reflection type Macbeth densitometer RD-1255 (manufactured by Sakata Inx). The ink ribbon used was a print pack VPM-P50STA dedicated to DPP-M1. The printing conditions were set to the standard settings of a printer driver (manufactured by Sony Corporation) for Macintosh (manufactured by Apple Inc.). Then, the color density was evaluated as the sum of the maximum values of the reflection densities of cyan, magenta, yellow, and black.

(Evaluation of Releasability) The releasability of the ink ribbon and the image receiving sheet during printing was visually observed and evaluated according to the following criteria. ：: Smooth printing without abnormal transfer such as heat fusion. △: Loud peeling sound ×: Abnormal transfer occurs. The evaluation results are shown in the table.

[0049]

[Table 1]

Claims (7)

[Claims] 1. A resin composition for forming a dye receiving layer of a thermal transfer recording image receptor, comprising: (1) polymer particles having a crosslinked structure or (2) an emulsion containing crosslinkable polymer particles. Resin composition for thermal transfer recording. 2. The thermal transfer recording resin composition according to claim 1, wherein the polymer particles (1) and (2) are formed of a monomer containing at least an aromatic vinyl monomer. 3. The method according to claim 1, wherein the polymer particles have at least 2
A copolymer of a polyfunctional monomer having two polymerizable unsaturated bonds and a monofunctional vinyl monomer, a copolymer of a crosslinkable monomer and a monofunctional vinyl monomer, or 2. The thermal transfer according to claim 1, comprising a copolymer of a polyfunctional monomer having at least two polymerizable unsaturated bonds in the molecule, a crosslinkable monomer and a monofunctional vinyl monomer. Recording resin composition. 4. The thermal transfer recording resin composition according to claim 3, wherein the content of the polyfunctional monomer is 0.1 to 20% by weight based on the whole monomer. 5. The resin composition for thermal transfer recording according to claim 3, wherein the content of the crosslinkable monomer is 0.1 to 30% by weight based on the whole monomer. 6. An image receiving body for thermal transfer recording, wherein the dye receiving layer is constituted by the resin composition according to claim 1. 7. A method for producing a thermal transfer recording image receiving body, wherein the resin composition according to claim 1 is applied to at least one surface of a substrate to form a dye receiving layer.