JPH11115325A - Manufacture of heat-sensitive image recording body - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve the transfer density, the image uniformity and the image durability by a method wherein a metallic ion-containing compound is fed to a thermal diffusion type coloring matter under an un-chelate state which remains on the surface of an image being formed on a thermal diffusion type coloring matter receiving layer. SOLUTION: For an image receiving layer 3, a binder for image receiving layer is made a basic component, and a metallic ion-containing compound and various kinds of additives can be added. In this case, their kinds, the blending amounts and the thickness of the image receiving layer 3 or the like may be appropriately selected depending on purposes. Also, a transfer sheet for image protective layer is a heat-transferrable sheet constituted in such a manner that an image protective layer 4 containing a metallic ion-containing compound is formed on a supporting body. Then, on a coloring matter image which is formed on the image receiving layer 3, the image protective layer 4 is heat- transferred. By this method, the metallic ion-containing compound is fed to an un-chelate coloring matter which remains on the surface of the image, and at the same time, the chelation reaction can be accelerated by utilizing the heat in the transfer.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing a thermal transfer image recording medium, and more particularly, to a thermal transfer image having a high transfer density, which is excellent in color tone and fixability of a printed image, has good storage stability and image durability. The present invention relates to a method for efficiently manufacturing a recording medium.

[0002]

2. Description of the Related Art Conventionally, as a method of obtaining a color hard copy, a color recording technique such as an ink jet method, an electrophotographic method, and a thermal transfer method has been studied. It has advantages such as easiness of operation and maintenance, downsizing and cost reduction of the device, and low running cost.

In the thermal transfer method, a transfer sheet having a heat-meltable ink layer on a support (hereinafter, also referred to as a thermal transfer recording material) is heated by a thermal head to remove ink from the heat-meltable ink layer. A method of melt-transfer onto an image-receiving sheet for thermal transfer recording, and a transfer sheet having an ink layer containing a heat-diffusible dye (sublimable dye) on a support, which is heated by a heat-sensitive head to remove the heat-diffusing ink from the ink layer. There are two types, the thermal diffusion transfer method (sublimation transfer method), in which the dye is transferred to an image receiving sheet for thermal transfer recording. The thermal diffusion transfer method uses the amount of the dye transferred according to the change in the thermal energy of the thermal head. Can be changed to control the gradation of the image, which is advantageous for full-color printing.

In the thermal transfer recording of the thermal diffusion transfer system, the dye used in the thermal transfer recording material is important, and the stability of the obtained image, that is, the light fastness and the fixing property are not good in the conventional one. There is a disadvantage that. Therefore, in order to improve these points, Japanese Patent Laid-Open Publication No.
Nos. 3, 59-109394 and 60-2398 disclose chelating dyes (chelating dyes) on a heat-sensitive transfer recording image-receiving sheet using a heat-diffusing dye capable of being chelated. An image forming method for forming an image by the method is disclosed.

However, these image forming methods are effective as methods for improving heat resistance and fixability, but sufficiently diffuse and chelate dyes transferred from the thermal transfer recording ink sheet during thermal transfer. Since it did not proceed, there was still dissatisfaction with the uniformity of color reproducibility of the transferred image and the fixability with unreacted dye. Immediately after printing, since unreacted dye is present on the surface of the dye receiving layer, the heat resistance and light resistance of the transferred image are not sufficient, and it is difficult to maintain image quality during image formation. .

On the other hand, in recent years, various types of ID cards represented by licenses such as automobile licenses, identification cards, membership cards with photos, authentication identification cards, business cards with photos, and the like have become widespread. A face image is often formed on the surface of these ID cards for identification. Since this face image has a gradation, it is also called a gradation information containing image. The gradation information-containing image is not limited to a face image, and is called a gradation information-containing image as long as the image has a gradation.

[0007] Further, in these ID cards, items concerning the ID card holder and other necessary information are formed by characters, figures, symbols and the like. These characters, figures, symbols and the like usually have no gradation and are formed in one color. Therefore, images of these characters, figures, symbols, and the like are referred to as character information containing images. Conventionally, in an ID card having a character information-containing image and a gradation information-containing image, the gradation information-containing image is formed by a silver halide photographic method, and the character information-containing image is formed by a heat melting type thermal transfer recording method. I have.

However, formation of an image containing gradation information by silver halide photography requires complicated steps such as exposure, development, fixing, bleaching, and washing with water. Therefore, in a site where an ID card is prepared quickly and in large quantities, a method of forming a gradation information-containing image by silver halide photography is not always an appropriate method. The present inventors have focused on the use of a heat-diffusible dye capable of being chelated in the production of this ID card,
Although he continued his research, he came across the following problems.

That is, a gradation information-containing image formed by a sublimation-type thermal transfer recording method using a sublimable dye capable of being chelated, the dye formed by the chelation reaction is present on the surface of the image receiving layer. Is not sufficiently durable. Furthermore, the diffusion and chelation of the sublimable dye migrating from the thermal transfer recording ink sheet during thermal transfer does not proceed sufficiently, and the sublimable dye that does not form a chelate diffuses into the protective layer. It is difficult to maintain image quality during formation.

The present invention has been made based on the above circumstances. That is, an object of the present invention is to provide a method for producing a heat-sensitive transfer image recording body having improved transfer density, image uniformity, image storability and image durability.

Under the circumstances described above, the present inventors have conducted intensive studies on the mass production and rapid production of ID cards having beautiful images, and as a result, the gradation information has been formed on the image receiving layer by a sublimation type thermal transfer recording system. Forming a text-containing image that describes necessary information while forming a text-containing image by, for example, a thermal melting type thermal transfer recording method, and further forming a metal on an unchelated heat diffusible dye remaining on the surface of the formed image. Supply of an ion-containing compound, for example, efficient production of a thermal transfer image recording medium comprising laminating an image protection layer containing a metal ion-containing compound on the surface of the gradation information-containing image and heating the layer; Method developed.

[0012]

According to the first aspect of the present invention, there is provided an image-receiving sheet for heat-sensitive transfer recording, comprising at least a heat-diffusible dye-receiving layer laminated on a support; Laminating an ink sheet for thermal transfer recording provided on a support with an ink layer containing a heat-diffusible dye capable of forming a chelate complex with the containing compound,
After forming an image on the heat-diffusible dye-receiving layer by heating according to a recording signal, supplying the metal ion-containing compound to the unchelated heat-diffusible dye remaining on the surface of the formed image. A method for producing a heat-sensitive transfer image recording material, wherein the image-receiving sheet for heat-sensitive transfer recording comprises at least a heat-diffusible dye-receiving layer laminated on a support, and a metal ion-containing compound. An ink layer containing a heat-diffusible dye capable of forming a chelate complex is superimposed on a thermal transfer recording ink sheet provided on a support, and the image is thermally diffused by heating according to a recording signal. Supplying a metal ion-containing compound to the non-chelated heat-diffusible dye remaining on the surface of the formed image after the formation on the conductive dye-receiving layer, and allowing the chelation reaction to proceed. A method for producing a thermal transfer image recording member, wherein.

[0013]

BEST MODE FOR CARRYING OUT THE INVENTION

[I] Layer Configuration of Thermal Transfer Image Recording Body FIG. 1 conceptually shows an example of a preferred embodiment of an ID card as one embodiment of a thermal transfer image recording body that can be produced by the present invention. The thermal transfer image recording body that can be produced by the present invention is not limited to the embodiment shown in FIG.

As shown in FIG. 1, an ID card 1 which can be manufactured according to the present invention comprises an ID card support 2.
And a gradation information-containing image (not shown) formed on the surface of the ID card support 2 and formed of a sublimable dye by a sublimation type thermal transfer method, and formed by a heat melting type transfer method or a sublimation type thermal transfer method. Image receiving layer 3 having a printed character information-containing image (not shown), image protecting layer 4 containing a metal ion-containing compound thermally transferred to the surface of the gradation information containing image in image receiving layer 3, and image protecting layer 4. And an ultraviolet curable resin layer 5 formed on the entire exposed surface of the image receiving layer 3;
It is composed of a writing layer 6 formed on the side opposite to the image receiving layer 3 of the card support 2.

[II] Production method of thermal transfer image recording medium (1) Thermal transfer recording image receiving sheet The thermal transfer recording image receiving sheet of the present invention is basically formed by laminating an image receiving layer on a support. -Support-Examples of the support include various papers such as paper, coated paper, and synthetic paper (polypropylene, polystyrene, or a composite material obtained by bonding them to paper), a vinyl chloride resin sheet, an ABS resin sheet, and the like. Various plastic films or sheets such as polyethylene terephthalate base film and polyethylene naphthalate base film,
Films and sheets formed of various metals, films and sheets formed of various ceramics, and the like can be given. In the support, a white pigment, for example, titanium white, magnesium carbonate, zinc oxide, barium sulfate, silica, talc, clay, calcium carbonate, etc., is added in order to enhance the sharpness of an image formed in a later step. Is preferred. The thickness of the support is usually 20
１０００1000 μm, preferably 20-800 μm,
It is appropriately selected from such a range.

-Image-Receiving Layer- The image-receiving layer contains a binder for the image-receiving layer as a basic component, and can preferably contain a metal ion-containing compound and various additives. Etc. may be appropriately selected depending on the purpose. 1. Binder for image receiving layer In general, binders for image receiving layer include, for example, polyvinyl chloride resin, copolymer resin of vinyl chloride and other monomers (eg, alkyl vinyl ether, allyl glycidyl ether, vinyl propionate, etc.), polyvinylidene chloride Resin, polyester resin, acrylate ester, methacrylate ester, epoxy resin, phenoxy resin, polyvinyl butyral, polyvinyl pyrrolidone, polycarbonate, polysulfone, polyarylate, polyparabanic acid, cellulose triacetate, styrene acrylate resin, vinyl toluene acrylate resin, polyurethane resin , A polyamide resin, a urea resin, a polycaprolactone resin, a styrene-maleic anhydride resin, a polyacrylonitrile resin, and the like. As the binder for the image receiving layer used in the present invention, a vinyl chloride resin, an epoxy resin, a phenoxy resin and the like are preferable.

These resins can be used alone or in combination of two or more. The above various resins may be newly synthesized and used, but commercially available products may also be used. In forming the image receiving layer, the above various resins are crosslinked by radiation, heat, moisture, a catalyst, or the like by utilizing their reactive active points (if there is no reactive active point, it is applied to the resin). Alternatively, it may be cured. In that case, a radiation-active monomer such as epoxy or acrylic, or a crosslinking agent such as isocyanate can be used.

If there is a practical requirement for the image formed in the present invention (for example, an ID card to be issued is required to have a predetermined heat resistance), a binder is required to satisfy such requirement. It is necessary to consider the type or combination of. Taking the heat resistance of an image as an example, if heat resistance of 60 ° C. or higher is required, it is preferable to use a binder having a Tg of 60 ° C. or higher in consideration of bleeding of a sublimable dye.

The type of binder can be selected arbitrarily.
A vinyl chloride resin is preferred in terms of image storability and the like. Examples of the vinyl chloride resin include a polyvinyl chloride resin and a vinyl chloride copolymer. Examples of the vinyl chloride copolymer include a copolymer of vinyl chloride and another comonomer containing vinyl chloride at a ratio of 50 mol% or more as a monomer unit.

Examples of the other comonomers include vinyl acetate, vinyl propylene acid, vinyl esters of fatty acids such as vinyl acetate and vinyl tallowate, acrylic acid, methacrylic acid, methyl acrylate, and ethyl methacrylate.
Acrylic acid or methacrylic acid such as butyl acrylate, 2-hydroxyethyl methacrylate, and 2-ethylhexyl acrylate and alkyl esters thereof, and maleic acid such as maleic acid, diethyl maleate, dibutyl maleate, and dioctyl maleate. Acids and alkyl alkyl esters thereof, methyl vinyl ether, 2-ethylhexyl vinyl ether, lauryl vinyl ether, palmityl vinyl ether, alkyl vinyl ethers such as stearyl vinyl ether and the like can be mentioned. Further, as the comonomer, other halogenated olefins such as ethylene, propylene, acrylonitrile, methacrylonitrile, styrene, chlorostyrene, itaconic acid and its alkyl esters, crotonic acid and its alkyl esters, dichloroethylene and trifluoroethylene, and cyclopentene And the like, such as cycloolefins, aconitic esters, vinyl benzoate, and benzoyl vinyl ether.

The vinyl chloride copolymer may be any of a block copolymer, a graft copolymer, an alternating copolymer, and a random copolymer. In some cases, it may be a copolymer with a compound having a peeling function such as a silicon compound. In addition to the vinyl chloride resin, a polyester resin can also be suitably used as an image receiving layer for sublimation type thermal transfer. Examples of the polyester resin that can be used in the present invention include compounds described in JP-A-58-188695 and JP-A-62-244696. Polycarbonate resins can also be used as a binder, and for example, various compounds described in JP-A-62-169694 can be used.

Next, the heat-resistant resin has good heat resistance and is not a resin having an extremely low softening point or glass transition point (Tg). It is suitably compatible with the vinyl chloride resin and is substantially colorless. Any known heat-resistant resin can be used as long as it is. The term “heat resistance” as used herein means that the resin itself does not undergo coloring such as yellowing when stored under heat, and the physical strength does not extremely deteriorate.

Examples of the heat-resistant resin satisfying the above conditions include a phenol resin, a melamine resin, a urea resin, and a ketone resin. Among them, a urea aldehyde resin and a ketone resin are particularly preferable. Urea aldehyde resin is obtained by condensation of urea and aldehydes (mainly formaldehyde), and ketone resin is obtained by condensation reaction of ketone and formaldehyde. Various resins are known depending on the starting ketone, and any of them can be used in the present invention.

Examples of the starting ketone include methyl ethyl ketone, methyl isobutyl ketone, acetophenone, cyclohexanone, methylcyclohexanone and the like. Examples of urea aldehyde resins that can be easily obtained include, for example, Laropearl A81 and Laropearl A1.
01 (manufactured by BASF) and a ketone resin such as Laropearl K80 (manufactured by BASF).

The binder selected from the various resins in the present invention is used for the purpose of improving physical properties such as increasing the film strength of the image receiving layer, preventing fusion during transfer of the sublimable dye, and preventing bleeding of the sublimable dye. Curing with an isocyanate-based curing agent, curing with an ultraviolet curable resin or the like may be performed. As a method for improving the physical properties of the image receiving layer, an appropriate additive may be added in addition to the curing agent.

2. Metal ion-containing compound Examples of the metal ion constituting the metal ion-containing compound include divalent and polyvalent metals belonging to Groups I to VIII of the periodic table. Among them, Al, Co, Cr,
Cu, Fe, Mg, Mn, Mo, Ni, Sn, Ti and Zn are preferred, and Ni, Cu, Co, Cr and Zn are particularly preferred.

The compound containing these metal ions is preferably an inorganic or organic salt of the metal and a complex of the metal. Specific examples include Ni ²⁺ , Cu ²⁺ , Co
Complexes represented by the following general formula containing ²⁺ , Cr ²⁺ and Zn ²⁺ are preferably used. [M (Q ₁ ) _k (Q ₂ ) _m (Q ₃ ) _n ] ^{p +} p (L ⁻ ) where M represents a metal ion, and Q ₁ , Q ₂ and Q ₃ are each represented by M. It represents a coordination compound capable of coordinating with a metal ion. These coordination compounds can be selected, for example, from the coordination compounds described in "Chelate Chemistry (5) (Nankodo)". Particularly preferred are coordination compounds having at least one amino group coordinated with a metal, and more specifically, ethylenediamine and its derivatives, glycinamide and its derivatives, picolinamide and its derivatives Can be

L is a counter anion capable of forming a complex,
Inorganic compound anions such as Cl, SO ₄ and ClO ₄ and organic compound anions such as benzene sulfonic acid derivatives and alkyl sulfonic acid derivatives are mentioned. Particularly preferred are tetraphenyl boron anion and its derivatives, and alkyl benzene sulfonic acid anions and It is a derivative.

K represents an integer of 1, 2 or 3, m represents 1, 2 or 0, and n represents 1 or 0, which represents whether the complex represented by the above general formula is tetradentate. , 6-dentate coordination or the number of Q ₁ , Q ₂ , Q ₃ ligands. p represents 1, 2 or 3. Examples of this type of metal ion-containing compound include those exemplified in US Pat. No. 4,987,049. The addition amount of the metal ion-containing compound is preferably 0.5 to 20 g / m ² ,
15 g / m ² is more preferred.

3. Additives A release agent, an antioxidant, a UV absorber, a light stabilizer, a filler (inorganic fine particles, organic resin particles), and a pigment may be added to the image receiving layer. Further, a plasticizer, a thermal solvent, or the like may be added as a sensitizer.

The release agent is used to improve the releasability between the thermal transfer recording ink sheet and the thermal transfer recording image receiving sheet. Examples of such release agents include silicone oils (including those called silicone resins); solid waxes such as polyethylene wax, amide wax, and Teflon powder; and fluorine-based and phosphate-based surfactants. Among them, silicone oil is preferable. This silicone oil is classified into a type that is simply added (simple addition type) and a type that is cured or reacted (curing reaction type).

In the case of the simple addition type, it is preferable to use a modified silicone oil (for example, a polyester-modified silicone resin, a urethane-modified silicone resin, an acryl-modified silicone resin, etc.) in order to improve the compatibility with the binder. The amount of addition of these simple addition type silicone oils cannot be determined uniformly since they may vary in various ways depending on the type, but generally speaking,
Usually, 0.1 to 50% by weight based on the binder for the image receiving layer
And preferably 0.5 to 20% by weight.

As the curing reaction type silicone oil,
Reaction curable types (for example, those obtained by reacting and curing an amino-modified silicone oil and an epoxy-modified silicone oil), photocurable types, catalyst-curable types, and the like. The addition amount of these curable silicone oils is preferably 0.5 to 30% by weight of the binder for the image receiving layer.

The release agent layer may be provided on a part of the surface of the image receiving layer by dissolving or dispersing the above-mentioned release agent in a suitable solvent and applying the resultant, followed by drying. Next, examples of the antioxidant include JP-A-59-182785.
No. 60-130735, JP-A-1-127287
And antioxidants described in Japanese Patent Application Laid-Open Publication No. H10-133, and known compounds for improving image durability in photographs and other image recording materials.

The UV absorber and the light stabilizer include:
JP-A-59-158287, JP-A-63-74686,
Nos. 63-145089, 59-196292, 62-229594, 63-122596, and 61
Compounds described in JP-A-283595 and JP-A-1-204788, and compounds known to improve image durability in photographs and other image recording materials can be mentioned.

Examples of the filler include inorganic fine particles and organic resin particles. Examples of the inorganic fine particles include silica gel, calcium carbonate, titanium oxide, acid clay, activated clay, and alumina. Examples of the organic fine particles include resin particles such as fluororesin particles, guanamine resin particles, acrylic resin particles, and silicon resin particles. Can be mentioned. These inorganic / organic resin particles vary depending on the specific gravity, but are preferably added in an amount of 0 to 30% by weight.

Representative examples of the pigment include titanium white, calcium carbonate, zinc oxide, barium sulfate, silica, talc, clay, kaolin, activated clay, and acid clay. Examples of the plasticizer include phthalates, trimellites, adipic esters, other saturated or unsaturated carboxylic esters, citrates, epoxidized soybean oil, epoxidized linseed oil, epoxy stearate epoxy , Phosphoric esters, phosphites, glycol esters and the like.

Examples of the thermal solvent (thermally fusible substance) include alcohols such as terpineol, menthol, 1,4-cyclohexanediol, and phenol; acetamide;
Amides such as benzamide, coumarin, esters such as benzyl cinnamate, ethers such as diphenyl ether and crown ether, camphor, ketones such as p-methylacetophenone, aldehydes such as vanillin and dimethoxybenzaldehyde, norbornene, stilbene and the like Monomolecular compounds represented by hydrocarbons, higher fatty acids such as margaric acid, higher alcohols such as eicosanol, higher fatty acid esters such as cetyl palmitate, higher fatty acid amides such as stearamide, higher amines such as behenylamine, etc. , Waxes such as carnauba wax, beeswax, paraffin wax, ester wax, montan wax, amide wax, ester gum, rosin derivatives such as rosin maleic resin, rosin phenol resin, phenol resin, keto Polymers represented by resins, epoxy resins, diallyl phthalate resins, terpene resins, aliphatic hydrocarbon resins, cyclopentadiene resins, polyolefin resins, polyolefin oxides such as polyethylene glycol and polypropylene glycol, and the like can be given. .

In the present invention, the total amount of the additives is usually in the range of 0.1 to 30% by weight based on the binder for the image receiving layer. -Other layers- In the ID card of the preferred embodiment of the present invention, a writing layer is usually formed on the surface of the support for the ID card opposite to the surface on which the image receiving layer is formed. When the ID card of the present invention is used as a car license or the like, it is particularly preferable to provide a writing layer. This is because the formation of the writing layer allows various information to be written on the ID card, which is convenient.

The writing layer is described in Japanese Patent Application Laid-Open No. 1-2
No. 05155, page 4, upper right column, line 14 to page 4, lower right column, line 2 will be replaced with the description of “writing layer”, and the detailed description thereof will be omitted. In order to more effectively prevent fusion between the image receiving layer and the ink layer of the thermal transfer recording ink sheet, a release agent (the silicone resin, modified silicone resin, silicone oil film or a cured product thereof) is applied to the surface of the image receiving layer. The contained release layer may be further laminated. The thickness of the release layer is usually 0.03 to 2.0 μm
It is.

A cushion layer or a barrier layer may be provided between the ID card support and the image receiving layer. By providing the cushion layer, it is possible to transfer and record an image corresponding to image information with good reproducibility with little noise. Examples of the material constituting the cushion layer include urethane resin, acrylic resin, ethylene-based resin, butadiene rubber, and epoxy resin. The thickness of the cushion layer is usually 1 to 50 μm, preferably 3 to 30 μm.
It is.

By providing the barrier layer, the diffusion of the sublimable dye into the support for the ID card can be prevented, and the bleeding of the dye in the support for the ID card can be prevented. Examples of the material constituting the barrier layer include a hydrophilic binder such as gelatin and casein, and a polymer having a high Tg. (2) Production of heat-sensitive transfer recording image-receiving sheet The heat-sensitive transfer recording image-receiving sheet is prepared by dispersing or dissolving the components for forming the image receiving layer in a solvent to prepare an image receiving layer forming coating solution. It can be formed by a coating method in which a working liquid is applied to the surface of the support and dried, or a lamination method in which a mixture having the components for forming the image receiving layer is melt-extruded and laminated on the surface of the support. Among these various methods, a coating method is preferable.

Examples of the solvent used in the above coating method include water, alcohols (eg, ethanol, propanol), cellosolves (eg, methyl cellosolve, ethyl cellosolve), aromatics (eg, toluene, xylene, chlorobenzene), ketones (eg, For example, acetone, methyl ethyl ketone), ester solvents (eg, ethyl acetate, butyl acetate, etc.), ethers (eg, tetrahydrofuran, dioxane), chlorine solvents (eg, chloroform, trichloroethylene), and the like.

For the coating, a conventionally known coating method using a gravure roll, an extrusion coating method, a wire bar coating method, a roll coating method and the like can be adopted. (3) Thermal Transfer Recording Ink Sheet The thermal transfer recording ink sheet basically includes an ink layer laminated on a support. -Support-As the support, any material can be used as long as it has good dimensional stability and can withstand heat during recording with a thermal head. Thin paper such as condenser paper and glassine paper, polyethylene terephthalate, and polyethylene naphthalate can be used. , Polyamide, polyimide, polycarbonate, polysulfone,
A heat-resistant plastic film such as polyvinyl alcohol cellophane or polystyrene can be used.

The thickness of the support is preferably 2 to 10 μm. The shape of the support is not particularly limited, and may be any shape such as a wide sheet or film, a narrow tape or card. —Ink Layer— The ink layer contains a heat diffusing dye and a binder as essential components. 1. Thermal diffusible dye The thermal diffusible dye used in the present invention is described in, for example,
No. 78893, No. 59-109349, Japanese Patent Application No. 2
-213303, 2-214719, 2-20
No. 3742, a cyan image forming dye capable of forming a bidentate chelate with at least the above-mentioned metal ion-containing compound (hereinafter referred to as cyan dye), a magenta image forming dye (hereinafter referred to as magenta dye) ) And yellow image forming dyes (hereinafter referred to as yellow dyes).

Preferably, a dye represented by the following general formula is used. X ¹ -N = N-X ² -G wherein X ¹ is required to complete an aromatic carbocyclic or heterocyclic ring in which at least one ring is composed of 5 to 7 atoms. Represents a collection of atoms, wherein at least one of the carbon atoms adjacent to the azo bond is a nitrogen atom or a carbon atom substituted with a chelating group. X ²
Represents an aromatic heterocyclic ring or an aromatic carbocyclic ring in which at least one ring is composed of 5 to 7 atoms. G represents a chelating group.

The thermal diffusible dye contained in the ink layer may be any of a yellow dye, a magenta dye and a cyan dye as long as the image to be formed is a single color. Also, depending on the color tone of the image to be formed,
Any two or more of the three dyes or other heat-diffusible dyes may be included. The amount of the heat diffusible dye to be used is generally 0.1 to ²⁰ g, preferably 0.2 to 5 g, per 1 m ^{2 of} the support.

2. As a binder of the binder-ink layer, a cellulose-added compound,
Cellulose resins such as cellulose esters and cellulose ethers; polyvinyl acetal resins such as polyvinyl alcohol, polyvinyl formal, polyvinyl acetoacetal, and polyvinyl butyral; polyvinyl pyrrolidone, polyvinyl acetate, polyacrylamide, styrene resins, poly (meth) acrylic acid Examples include vinyl-based resins such as system-based esters, poly (meth) acrylic acid, and (meth) acrylic acid copolymers, rubber-based resins, ionomer resins, olefin-based resins, and polyester resins.

Among these resins, polyvinyl butyral, polyvinyl acetoacetal or cellulose resin having excellent storage stability is preferable. One of the above various binders can be used alone, or two or more of them can be used in combination. The weight ratio between the binder and the heat-diffusing dye is preferably from 1:10 to 10: 1, and particularly preferably from 2: 8 to 7: 3. 3. Other Optional Components Various additives can be appropriately added to the ink layer.

The additives include silicone resin, silicone oil (reaction curing type is also possible), silicone modified resin, fluororesin, surfactant, and peelable compounds such as waxes, fine metal powder, silica gel, metal oxide Agent, filler such as carbon black, resin fine powder, etc., curing agent capable of reacting with binder component (for example, radiation-active compounds such as isocyanates, acrylics and epoxies)
And the like.

Further, as an additive, a heat-fusible substance for promoting transfer, for example, compounds described in JP-A-59-106997, such as waxes and higher fatty acid esters, may be mentioned. —Other Layers— The thermal transfer recording ink sheet is not limited to a two-layer structure including a support and an ink layer, and may have other layers.

For example, an overcoat layer may be provided on the surface of the ink layer for the purpose of preventing fusion with the image receiving sheet for thermal transfer recording or set-off (blocking) of the heat diffusible dye. Further, the support may have an undercoat layer for the purpose of improving the adhesiveness to the binder and preventing transfer and dyeing of the dye to the support. Further, a sticking prevention layer may be provided on the back surface of the support (opposite side of the ink layer) for the purpose of preventing fusion or sticking of the head to the support and wrinkling of the thermal transfer recording ink sheet. .

The thickness of the above-mentioned overcoat layer, undercoat layer and anti-sticking layer is usually 0.1 to 1 μm. (4) Production of Ink Sheet for Thermal Transfer Recording The ink sheet for thermal transfer recording is prepared by dispersing or dissolving the above-mentioned various components for forming an ink layer in a solvent to prepare an ink layer-forming coating liquid. Coating on the surface of the support,
It can be manufactured by drying.

One or more of the above binders are used by dissolving them in a solvent or dispersing them in latex form. As the solvent, water, ethanol, tetrahydrofuran, methyl ethyl ketone, toluene, xylene,
Examples thereof include chloroform, dioxane, acetone, cyclohexane, and normal butyl acetate.

For the coating, a conventionally known gravure roll-coating method using a gravure roll, an extrusion coating method, a wire bar coating method, a roll coating method and the like can be adopted. The ink layer may be formed on the entire surface or a part of the surface of the support as a layer containing a monochromatic heat diffusible dye, a yellow ink layer containing a yellow dye, a magenta dye containing a magenta dye. The ink layer and the cyan ink layer containing the cyan dye may be formed at a constant repetition along the planar direction.

Further, in addition to the three ink layers arranged along the plane direction, a black ink layer containing a black image forming substance may be interposed. Regarding the black ink layer, a clear image can be obtained by either the diffusion transfer type or the melt transfer type. One of the preferred embodiments is that a layer containing a metal ion-containing compound which can be thermally transferred and which can be used in the present invention described later is separately coated on the same support. The thickness of the ink layer thus formed is usually
0.2 to 10 μm, preferably 0.3 to 3 μm
It is.

The ink sheet for thermal transfer recording may be provided with a perforation or provided with a detection mark for detecting the position of an area having a different hue, thereby facilitating use. (5) Image formation (thermal transfer recording)-Formation of image containing gradation information-The ink layer of the thermal transfer recording ink sheet and the image receiving layer of the thermal transfer recording image receiving sheet are overlapped, and the ink layer and the image receiving layer are formed. Apply thermal energy imagewise to the interface.
Then, the sublimable dye in the ink layer is vaporized or sublimated by an amount corresponding to the applied thermal energy, and is transferred to the image receiving layer side and received. As a result, a gradation information-containing image is formed on the image receiving layer.

As the heat source for giving the thermal energy,
A thermal head is generally used. In addition, a conventionally known one such as a laser beam, an infrared flash, and a hot pen can be used. As a method of applying the heat energy, even if it is performed from the sublimation type thermal transfer recording ink sheet side,
It may be carried out from the ID card support side or from both sides, but if priority is given to the effective use of thermal energy, it is desirable to carry out from the sublimation type thermal transfer recording ink sheet side.

When a thermal head is used as a heat source for applying thermal energy, the applied thermal energy can be changed continuously or in multiple steps by modulating the voltage or pulse width applied to the thermal head. When laser light is used as a heat source for applying heat energy, the applied heat energy can be changed by changing the light amount or irradiation area of the laser light.

In this case, in order to easily absorb the laser beam, a laser beam absorbing material (for example, carbon black or near-infrared absorbing material in the case of a semiconductor laser) may be present in the ink layer or in the vicinity of the ink layer. .
When a laser beam is used, the thermal transfer recording ink sheet and the thermal transfer recording image receiving sheet may be sufficiently adhered to each other. If a dot generator having a built-in acousto-optical element is used, heat energy corresponding to the size of a halftone dot can be applied.

When an infrared flash lamp is used as a heat source for applying heat energy, the heating may be performed through a colored layer such as black as in the case of using a laser beam. Alternatively, heating may be performed through a pattern or a halftone pattern that continuously expresses the shading of an image, such as black, or a negative pattern corresponding to the negative of the above-described pattern with a colored layer such as black on one surface. Heating may be performed in combination.

The thermal energy may be applied from the thermal transfer recording ink sheet side, from the thermal transfer recording image receiving sheet side, or from both sides, with priority given to the effective use of thermal energy. If you let
It is desirable to perform the heat transfer recording from the ink sheet side. By the above-described thermal transfer recording, a one-color image can be recorded on the image receiving layer of the thermal transfer recording image-receiving sheet. However, according to the following method, a color image of a color photographic tone composed of a combination of each color can also be obtained.

For example, by sequentially replacing the heat-sensitive transfer recording sheets for yellow, magenta, cyan and, if necessary, black, and performing heat transfer according to each color, a color photographic color image composed of a combination of each color is obtained. You can also. In this case, after each color printing, the metal ion-containing compound may be supplied to the heat-diffusible dye in an unchelated state remaining on the formed image surface, or after printing multiple colors,
The metal ion-containing compound may be supplied to the non-chelated thermal diffusible dye remaining on the formed image surface, or the unchelated thermal diffusible dye remaining on the formed image surface after full-color printing May be supplied with a metal ion-containing compound.

The following method is also effective. That is,
Instead of using the thermal transfer recording ink sheet of each color as described above, a thermal transfer recording ink sheet having an area previously formed separately for each color is used.

Then, first, the yellow color separation image is thermally transferred using the yellow area, then the magenta color separation image is thermally transferred using the magenta area, and thereafter, yellow, magenta, and cyan are sequentially repeated. And, if necessary, a method of thermal transfer in the order of the black color separation image. In this case, if a layer containing a metal ion-containing compound is provided after one set of separately applied ink layers of the thermal transfer recording ink sheet, the layer containing the metal ion-containing compound is formed following the dye image formation. It can be thermally transferred and is efficient.

Although it is possible to obtain a color photographic color image by this method, more advantageously, this method does not require replacement of the thermal transfer recording heat-sensitive sheet as described above. There is. -Formation of text information-containing image- The text information-containing image is obtained by heating a conventionally known heat-melt type thermal transfer recording ink sheet having a heat-meltable ink layer on a support in an image-wise manner using a laser or a thermal head. Then, it can be formed by melt-transferring the hot-melt ink to the image receiving layer. Further, a character information-containing image can be formed by a sublimation type thermal transfer recording method. (6) Formation of Image Protective Layer Even though an image is formed on the image receiving layer in the step (5), generally, the concentration of the heat diffusing dye is often higher on the surface of the image receiving layer. There is also a heat-diffusible dye remaining on the surface without being chelated. In such a case, the image storability (for example, light resistance) and fixability of the formed dye image are insufficient. In addition, the heat diffusible dye capable of forming a chelate often has a different color tone between an unchelated state and a chelated state, and if both exist in the formed image, color turbidity occurs and sufficient color reproducibility cannot be obtained.

In the present invention, an image protective layer containing a metal ion-containing compound is thermally transferred on a dye image formed on an image receiving layer using a transfer sheet for an image protective layer described below, and the like, so that the image protective layer remains on the image surface. The metal ion-containing compound can be supplied to the unchelated dye, and the chelation reaction can be advanced by utilizing heat at the time of transfer. This not only forms a completely chelated, stable, heat-diffusing dye image without color turbidity, but also improves fixability, and prevents dye bleeding or bleed-out due to light, heat, etc. The light storage stability and heat storage stability are improved.

The image protective layer containing the metal ion-containing compound may be transferred uniformly to the entire image receiving layer on which the dye image is formed, or may be transferred only on the dye image. A thermal head is generally used as a heat source for providing thermal energy for thermally transferring an image protective layer containing a metal ion-containing compound, and other known heat sources such as a laser beam, an infrared flash, a hot pen, a hot stamp, and the like. Can be used. The heat source for performing image formation and the heat source for thermally transferring the image protective layer may be the same or different, but in the case of the same, both operations can be performed by one heat source, and the apparatus can be downsized. Is preferable. (7) Transfer Sheet for Image Protection Layer The transfer sheet for image protection layer is basically a heat transferable sheet having an image protection layer containing a metal ion-containing compound formed on a support. This image protection layer may be provided separately from the ink layer on the same support of the thermal transfer recording ink sheet, or may be provided on a different support from the thermal transfer recording ink sheet. There may be.
When provided on the same support as the thermal transfer recording ink sheet, the length required to form one screen is at least for one screen after the three or four color ink layers provided face-sequentially. In a preferred embodiment, a protective layer containing a metal ion-containing compound is provided.

As the support used for the transfer sheet for the image protective layer, those which can be used for the heat-sensitive transfer ink sheet in both materials and thicknesses are suitably used. A sticking prevention layer may be provided on the back surface of the support (on the side opposite to the transfer layer) for the purpose of preventing the head from fusing or sticking to the support, and preventing wrinkling of the present transfer sheet. The image protection layer contains at least one metal ion-containing compound. Examples of the metal ion-containing compound suitably used here include a metal ion-containing compound contained in the image receiving sheet for thermal transfer recording. The content of the metal ion-containing compound is preferably 5 to 100%, more preferably 20 to 80% of the whole image protective layer.

In addition, the image protective layer contains a thermoplastic resin, a heat-fusible compound, a UV (ultraviolet) absorber, an antioxidant, a light stabilizer, a plasticizer, etc. as long as the object of the invention is not impaired. Can be. As the thermoplastic resin, the compounds exemplified as the binder for the image receiving layer and the binder for the ink layer can be used. The thermoplastic resin is usually contained in an amount of 0 to 95%, preferably 20 to 80% of the whole image protective layer.

The heat-meltable compound is a compound which is solid at room temperature and becomes liquid when heated. Usually, waxes, oils and fats, higher fatty acids and their derivatives, higher alcohols and their derivatives are preferably used. Specific examples of the heat-fusible compound include vegetable waxes such as carnauba wax, wood wax, ouriculi wax and espal wax; animal waxes such as beeswax, insect wax, shellac wax and spermaceti; paraffin wax, microcrystal wax, polyethylene wax, ester And waxes such as mineral waxes such as montan wax, ozokerite and ceresin. In addition to these waxes, palmitic acid, stearic acid, margaric acid and wax Higher fatty acids such as henic acid; higher alcohols such as palmityl alcohol, stearyl alcohol, behenyl alcohol, marganyl alcohol, myricyl alcohol and eicosanol; cetyl palmitate, myricyl palmitate, Higher fatty acid esters such as cetyl phosphate and myricyl stearate; amides such as acetamide, propionamide, palmitic amide, stearic acid amide and amide wax; and higher amines such as stearylamine, behenylamine and palmitylamine Is mentioned.

The ultraviolet absorber is particularly important when an ultraviolet curable resin layer is laminated on the surface of the image receiving layer including the image protective layer in an ID card or the like, particularly for the purpose of enhancing the image protection effect. In this case, the ultraviolet absorber, when the image protective layer is a single layer having an adhesive ability, in the image protective layer transfer sheet, when the core sheet and a plurality of layers having an adhesive layer, the core sheet and And / or contained in the adhesive layer.

When the image protective layer contains an ultraviolet absorber, it is possible to prevent bleeding of the gradation information-containing image caused by the irradiation of ultraviolet light for forming the ultraviolet curable resin layer. As the ultraviolet absorber, JP-A-59-15
No. 8287, No. 63-74686, No. 63-1450
No. 89, No. 59-196292, No. 62-22959
No. 4, 63-122596, 61-283595
And JP-A-1-204788.

Further, conventionally known compounds such as salicylic acid esters, benzophenones, benzotriazoles, cyanoacrylates and acrylonitrile-based substances which improve the image durability can also be used. In addition, the same heat stabilizer, light stabilizer and plasticizer that can be added to the image receiving layer can be suitably used. When an image protective layer containing a metal ion-containing compound is provided on a support, a transferability control layer for optimizing adhesiveness and transferability can be provided between the support and the image protective layer. The thickness of the image protective layer is usually from 0.2 to 10 μm, preferably from 0.5 to 5.0 μm.

[0075]

EXAMPLES The present invention will be described in more detail with reference to the following Examples, but it should not be construed that the present invention is limited to these Examples. In the following, “parts” means “parts by weight”. (Example 1) -Manufacture of ink sheet for thermal transfer recording- A coating solution for forming an ink layer having the following composition was wire-bar coated on a surface of a 6 μm-thick polyethylene terephthalate film [manufactured by Toray Industries, Inc.] as a support. According to the method, the composition is coated and dried so that the thickness after drying becomes 1 μm, and a nitro containing 40% by weight of a silicone resin [SP-2105, manufactured by Dainichi Seika Co., Ltd.] is formed on the back surface where the ink layer is not formed. Cellulose solution with a dry film thickness of 0.2
The ink sheet for thermal transfer recording was obtained by coating and drying to a thickness of μm and performing a back surface treatment coat.

Coating liquid for forming ink layer; Thermal diffusible dye 3.0 parts Nitrocellulose 3.0 parts [Celnova BTH1 / 2, manufactured by Asahi Kasei Kogyo Co., Ltd.] Methyl ethyl ketone 44.0 parts Dioxane ... 40.0 parts Cyclohexanone 10.0 parts. -Production of an image receiving sheet for thermal transfer recording- A wide white chloride having a thickness of 750 μm obtained by thermally welding a hard transparent vinyl chloride sheet having a thickness of 150 μm on both sides of a hard white vinyl chloride sheet having a thickness of 450 μm. By cutting the vinyl sheet, a support having a card size of 54.0 mm × 85.5 mm in length and width was obtained.

A coating solution for an image receiving layer and a coating solution for an adhesive layer having the following compositions are coated on the above support by a wire bar method, and the solvent is removed by drying to form an image receiving layer having a thickness of 8 μm and a thickness of 2 μm. Was formed.

Coating solution for forming image receiving layer; polyvinyl chloride resin 5.5 parts [TK600, manufactured by Shin-Etsu Chemical Co., Ltd.] containing metal ions Compound: 4.0 parts [[Ni (C ₂ H ₅ NHCH ₂ CH ₂ NH ₂ )] ²⁺ [(C ₆ H ₅ ) ₄ B] ^{2 -} ] Polyester modified silicone resin 0.5 parts [X-24-8300, manufactured by Shin-Etsu Chemical Co., Ltd.] Dioxane 40.0 parts Methyl ethyl ketone 40.0 parts Cyclohexanone 10 0.0 part Coating solution for forming adhesive layer; Polyester-based resin 10.0 parts [Pesregin S-110, manufactured by Takamatsu Yushi Co., Ltd. Methyl ethyl ketone · · · · · · 60.0 parts.

Next, on the surface of the support opposite to the image receiving layer, a coating solution for a writing layer having the following composition is applied by reverse coating using a gravure roll formed by partially etching and dried. The thickness is 3.5μ
m writing layers were formed.

Coating solution for writing layer; saturated polyester resin 90.0 parts [Byron 200, manufactured by Toyobo Co., Ltd.] Calcium carbonate 25.0 parts (Shiraishi calcium, etc., brilliant 15) Mixed solvent 400.0 parts [Toluene / methyl ethyl ketone (weight ratio 1: 1)]. -Production of Transfer Sheet for Image Protective Layer- A coating solution for an image protective layer having the following composition containing a metal ion-containing compound is coated on a surface of a polyethylene terephthalate film (manufactured by Toray Industries, Ltd.) having a thickness of 6 μm as a support by a wire bar coating method. Was applied and dried so as to have a dry film thickness of 1 μm, and the same back surface treatment as that for the above-mentioned thermal transfer recording ink sheet was performed on the back surface side to prepare a transfer sheet for an image protective layer.

Coating solution for image protective layer: Saturated polyester resin 7.0 parts [Byron 20-SS, manufactured by Toyobo Co., Ltd.] Metal ion-containing compound · · · · · · 3.0 parts _{[[Ni (C 2 H 5} NHCH 2 CH 2 NH 2)] 2+ [(C 6 H 5) 4 B] 2- Methyl ethyl ketone 70.0 parts Dioxane 20.0 parts. -Image formation- First, the ink layer of the thermal transfer recording ink sheet and the image receiving layer of the thermal transfer image receiving sheet are overlapped, and a thermal head is applied from the support side of the thermal transfer recording ink sheet under the following conditions. An image was formed. Linear density in main scanning and sub-scanning: 8 dots / mm Recording power: 0.6 W / dot Recording time of thermal head: Heating time was adjusted stepwise from 2 ms to 20 ms. Next, the ink sheet for thermal transfer recording and the image receiving sheet for thermal transfer recording were peeled off, and an image was transferred and formed on the image receiving sheet for thermal transfer recording.

Further, the formed image surface was brought into contact with the image protective layer of the transfer sheet for an image protective layer, and the same thermal head used for image formation was applied thereto to thermally transfer the image protective layer on the image surface under the following conditions. . Linear density in main scanning and sub-scanning: 8 dots / mm Recording power: 0.6 W / dot Recording time of thermal head: Transfer over the entire image in 20 msec The thermal transfer image recording material obtained was evaluated as follows. .

Chelate reaction rate: The reflection spectrum before and after the transfer of the metal ion-containing compound layer was measured (using a self-recording spectrophotometer U-3200 manufactured by Hitachi, Ltd.), and the reaction rate was measured from the spectrum intensity.

Heat resistance (heat-resistant image storage stability): A heat-sensitive transfer recording image receiving sheet on which an image has been recorded is heated at 77 ° C. and a relative humidity of 80%.
, And visually checked for bleed-out of the dye and the presence or absence of discoloration or fading of the dye, and also measured and determined using a spectrophotometer and an optical densitometer. A: No discoloration or fading of the dye is observed.・ ・ ・: Discoloration or fading of the pigment is slightly observed. Δ: Discoloration or fading of the pigment is observed. X: Discoloration or fading of the dye is remarkable.

Lightfastness (lightproof image storage stability): After exposing the image-receiving sheet for thermal transfer recording on which an image has been recorded with a xenon weather meter (70,000 lux) for 72 hours, the image is observed silently, and a spectrophotometer and It was determined by measuring with an optical densitometer. A: No discoloration or fading of the dye is observed.・ ・ ・: Discoloration or fading of the pigment is slightly observed. Δ: Discoloration or fading of the pigment is observed. X: Discoloration or fading of the dye is remarkable.

Fixing property of the dye: The image receiving sheet for thermal transfer recording on which an image was recorded faced the image receiving sheet for thermal transfer recording on which the image of the present invention was not recorded, and a load of 40 g / cm ² was applied thereto. After standing for 48 hours, the transfer density of the dye transferred to the image receiving sheet for thermal transfer recording where no image was recorded was judged. A: No transferred dye is observed at all.・ ・ ・: The transferred dye density was less than 0.10. Δ: The transferred dye density is 0.10 or more, 0.15
It was below. X: The density of the transferred dye was 0.15 or more. (Example 2) A thermal transfer image recording material was prepared and evaluated in the same manner as in Example 1 except that the coating solution for the image protective layer was changed to the following composition. Coating liquid for image protective layer; cellulose acetate 7.0 parts [manufactured by Kanto Chemical Co., Ltd.] Metal ion-containing compound ... ........... 3.0 parts _{[[Ni (C 2 H 5} NHCH 2 CH 2 NH 2)] 2+ [(C 6 H 5) 4 B] 2-] , Methyl ethyl ketone: ... 80.0 parts Cyclohexanone ... 10.0 parts. (Example 3) The same procedure as in Example 1 was carried out except that a coating liquid for a transferability control layer having the following composition was provided so as to have a dry film thickness of 1.0 µm before coating the image protective layer. Thus, a thermal transfer image recording medium was prepared and evaluated. Coating solution for transfer control layer; Microcrystalline wax 9.5 parts [HiMic-2065, manufactured by Wax Co., Ltd.] Ethylene-vinyl acetate copolymer 0.5 parts [EV-210, manufactured by DuPont-Mitsui Polychemicals Co., Ltd.] Toluene 70 0.0 parts Methyl isobutyl ketone 10.0 parts. (Example 4) Before coating the image protective layer, a coating liquid for a transferability control layer having the following composition was applied on a support to a dry film thickness of 0.5.
An image was formed and evaluated in the same manner as in Example 2 except that the coating was performed so that the thickness was adjusted to 120 μm, and the coating was cured by heating at 120 ° C. for 10 seconds. Coating solution for transferability control layer; Silicone resin 5.0 parts [TRP-6700, manufactured by Toshiba Silicone Co., Ltd.] Curing agent 0.05 parts [CM670, manufactured by Toshiba Silicone Co., Ltd.] Toluene .... 94.95 parts. Example 5 A heat-sensitive transfer image was prepared in the same manner as in Example 3 except that the coating solution for the image protective layer was changed to the following composition and the image protective layer was provided on the image surface so that the dry film thickness became 2.0 μm. A recording was prepared and evaluated. 5.0 parts of vinyl chloride resin [S Medica V1330E, Sekisui Chemical Co., Ltd.] Metal ion containing compounds ........ 3.0 parts _{[[Ni (C 2 H 5} NHCH 2 CH 2 NH 2)] 2+ [(C 6 H 5) 4 B] 2-] UV absorbers .... 2.0 parts [UVINUL N-35, manufactured by BASF] Methyl ethyl ketone 0 parts Cyclohexanone 10.0 parts. (Example 6) Three types of coating liquids for thermal transfer recording ink sheets were prepared with the same composition as in Example 1 using dyes of three colors, yellow, magenta, and cyan, on the same support. Coating was performed in the order of the surface. Further, an image protection layer containing a metal ion-containing compound having the same composition as that of Example 5 was provided on a part of the same support to prepare an ink sheet for thermal transfer recording and a transfer sheet for image protection layer. Using the same heat-sensitive transfer recording image-receiving sheet as in Example 1, an image protective layer was transferred under the same conditions as in Example 1 on an image formed by overprinting three color inks under the same conditions as in Example 1. The obtained thermal transfer image recording material was evaluated. Example 7 An image was formed in the same manner as in Example 6, except that the support was changed to a transparent polyester film having a thickness of 120 μm (trade name: Lumirror # 120, manufactured by Toray Industries, Inc.). The image protective layer was transferred thereon, and the obtained thermal transfer image recording material was evaluated. (Comparative Example 1) A thermal transfer image recording material was prepared and evaluated in the same manner as in Example 1, except that the image protective layer containing the metal ion-containing compound was not transferred onto the dye image. (Comparative Example 2) A thermal transfer image recording material was prepared and evaluated in the same manner as in Example 2 except that the image protective layer was changed to one containing no metal ion-containing compound as in the following composition. Coating solution for image protective layer; cellulose acetate 10.0 parts methyl ethyl ketone 80.0 Part Cyclohexanone ... 10.0 parts. (Comparative Example 3) The dye image formed in Example 1 was replaced with
A heat-transferred image recording material was prepared in the same manner as in Example 1, except that the heat treatment was performed under the same conditions as those for transferring the image protective layer of Example 1 via a 6 μm-thick polyester film subjected to only the back surface treatment. Created and evaluated.

[0087]

[Table 1] (Examples 8 to 14) Instead of thermally transferring the image protective layer to the image surface formed in Examples 1 to 7 using a thermal head, a silicone rubber roller for hot stamping is used.
(Rubber hardness 75), temperature 170 ° C, pressure 20kg /
Each of the image protective layers was thermally transferred by thermocompression bonding at 2 cm ² for 2 seconds. When the obtained thermal transfer image recording medium was evaluated, the same results as in Examples 1 to 7 were obtained.

[0088]

According to the method for producing a thermal transfer image recording medium of the present invention, it is possible to efficiently produce a thermal transfer image recording medium having improved transfer density, image uniformity, image storability and image durability. Can be.

[Brief description of the drawings]

FIG. 1 is a perspective view showing one embodiment of a thermal transfer image recording body that can be manufactured according to the present invention.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 ID card 2 ID card support 3 Image receiving layer 4 Image protection layer 5 UV curable resin layer 6 Writing layer

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Atsushi Nakajima 1 Sakuracho, Hino-shi, Tokyo Konica Corporation (72) Inventor Tatsuichi Maebashi 1 Sakuracho, Hino-shi, Tokyo Konica Corporation (72) Invention Toshihisa Takeyama 1 Sakuracho, Hino-shi, Tokyo Konica Corporation

Claims (2)

[Claims] An image-receiving sheet for thermal transfer recording, comprising a support and at least a heat-diffusible dye-receiving layer laminated on a support, and an ink layer containing a heat-diffusible dye capable of forming a chelate complex with a metal ion-containing compound. An image is formed on the heat-diffusible dye-receiving layer by superimposing a heat-sensitive transfer recording ink sheet provided on a support and heating in accordance with a recording signal. A method for producing a thermal transfer image recording material, comprising supplying a metal ion-containing compound to a heat-diffusible dye in a chelated state. 2. An image-receiving sheet for thermal transfer recording in which at least a heat-diffusible dye-receiving layer is laminated on a support, and an ink layer containing a heat-diffusible dye capable of forming a chelate complex with a metal ion-containing compound. An image is formed on the heat-diffusible dye-receiving layer by superimposing a heat-sensitive transfer recording ink sheet provided on a support and heating in accordance with a recording signal. A method for producing a heat-sensitive transfer image recording material, characterized in that a metal ion-containing compound is supplied to a heat-diffusible dye in a chelated state and a chelation reaction proceeds.