JP2005125754A - Image formed material and its image forming method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an image formed material wherein electrified preventive effect, conveyance aptitude to occurrence of electrified charged preventive effect and conveyance aptitude and treatment property to occurrence of static electricity is improved without following deterioration of storage, scratch resistance of a protective layer and deterioration of adhesion, and to provide its image forming method. <P>SOLUTION: For the image formed material prepared by using a thermal copying transfer system for transferring a protective transfer layer by using a thermal transfer sheet to which a peelable protective transfer layer is provided, an electric resistance measured by a salt bridge method of the heat transfer image receiving sheet before the protective transfer layer is transferred 1×10<SP>8</SP>-1×10<SP>12</SP>Ω/square, the transferred protective transfer layer is provided, and an electric resistance measured by the salt bridge method to image receiving face side of the image formed material wherein a layer coated to an opposite side to the image formed side is removed, is 1×10<SP>8</SP>-1×10<SP>12</SP>Ω/square to feature the image formed material. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a thermal transfer image receiving sheet, an image formed product formed by a thermal transfer method using a thermal transfer sheet having at least a protective transfer layer, and an image forming method thereof, and more particularly, in a thermal transfer method in which a protective transfer layer is transferred. In particular, the present invention relates to an image formed article having excellent antistatic properties without impairing scratch resistance and an image forming method thereof.

  Conventionally, as a color or monochrome image forming technique, an ink sheet containing a heat diffusible dye having a property of diffusing and transferring by heating is opposed to an image receiving layer of an image receiving sheet, and a thermal printing unit such as a thermal head or a laser. An image forming method is known in which an image is formed by transferring a heat diffusible dye to an image receiving layer in an image-like manner. Such a thermal transfer system is well-established as a method that enables image formation with digital data, does not use a processing solution such as a developer, and can form a high image quality comparable to a silver salt photograph.

  However, with respect to the storage stability and durability of the formed image, the quality is not yet reached as compared with silver salt photography.

  For the purpose of improving the stability of the obtained image, particularly fixing property and light resistance, a heat-sensitive transfer material using a chelatable heat-diffusible dye (hereinafter also referred to as post-chelate dye) and an image forming method thereof (post-chelation) Technology) is disclosed in, for example, JP-A-59-78893, 59-109349, 60-2398 and the like.

  In addition, as a technique for improving the mechanical durability (abrasion resistance, sebum resistance, etc.) of an image formed by a dye thermal transfer method, there is a technology for forming a transparent protective layer on the image by a thermal transfer method after image formation. A method using the image obtained by the post-chelation technique has been proposed (for example, see Patent Document 1).

  When an image is formed by the thermal sublimation transfer method, the thermal transfer sheet and thermal transfer image receiving sheet are overlapped and transported through the printer while being heated, so static electricity is generated and the transport is hindered, or the dye receiving layer surface of the thermal transfer image receiving sheet There is a problem that dust or the like adheres to the surface and color loss occurs. Further, as a means for forming the protective layer as described above, there is a method of transferring the protective layer onto an image formed using a thermal transfer sheet provided with a transfer layer in advance. Although it is performed using a printer, there is a problem that a large amount of static electricity is generated when the protective layer is peeled off from the thermal transfer sheet, resulting in poor conveyance of the transfer target or thermal transfer sheet in the thermal printer. .

  In addition, when a plurality of image formations are stacked after printing, the image receiving sheets may be brought into close contact with each other due to static electricity, so that a so-called defectiveness in which the image formations cannot be bundled compactly may occur.

  In order to solve such a problem, a method of suppressing the generation of static electricity by providing an antistatic layer on the transfer body (ribbon) or containing an antistatic agent is disclosed in, for example, JP-A Nos. 9-52454 and 7-179071. No. 7-179072, No. 6-55868, No. 6-99670, No. 10-81078, No. 10-118565, No. 10-119444, No. 8-300842, No. 9-156244, No. 9-295465 has been proposed, and recently, an antistatic technique has been proposed (see, for example, Patent Documents 2 to 5). However, the method proposed above has not yet sufficiently prevented charging of the transfer medium (image receiving paper).

  Further, methods for suppressing the generation of static electricity by providing an antistatic layer or containing an antistatic agent on the back surface of the transfer target (image receiving paper) are disclosed in, for example, JP-A-4-366688, JP-A-5-58064, JP-A-7. -1845, 8-1775035, 9-207462, 10-35116, 10-44624, 10-58846, 11-157226, 11-165469, etc. Yes. However, the proposed method of providing a conductive layer on the back surface is not sufficient as an effect of removing static electricity generated on the image receiving surface side.

  JP-A-5-64979, JP-A-6-155949, JP-A-7-32754, JP-A-7-290845, JP-A-8-52945, JP-A-10-324072, JP-A-10-329432, JP-A-11-78255. 11-321125, etc. disclose a method of providing a conductive layer on the image receiving surface side. However, even with these techniques, the image forming product having a protective transfer layer has insufficient antistatic effect. there were. Compared to the image forming method that does not peel and transfer the protective layer, in the method of peeling and transferring the protective layer, a large amount of electric charge is generated or the conductive layer is destroyed due to heat during transfer of the protective layer. It is assumed that the effect is not fully demonstrated.

  Furthermore, a method for containing an antistatic agent in the protective layer has been disclosed as an antistatic agent for the image-formed product having such a protective transfer layer (see, for example, Patent Documents 6 and 7). These proposed methods are effective means for preventing the electrostatic charge of an image-formed product having a protective transfer layer, but have the problem that the durability and storage stability, which are inherent properties of the protective layer, are reduced. .

In addition, in the thermal transfer system, a method using a cellulose resin for a back layer provided on an image receiving sheet has been proposed (see, for example, Patent Documents 8 and 9). However, in these disclosed patent documents, there is no mention or suggestion regarding the suggestion regarding the cellulose resin and the charging property, or the improvement of the charging property by combining with the conductivity measured by the salt bridge method. It hasn't been done.
JP 2001-168244 A JP 2000-103175 A JP 2000-103178 A JP 2000-272254 A JP 2001-1653 A Japanese Patent Laid-Open No. 11-105437 JP 2003-145946 A JP-A-10-297113 JP-A-11-181226

  The present invention has been made in view of the above-mentioned problems, and its purpose is to prevent the antistatic effect, transportability against static electricity generation, and separation without causing deterioration of storage stability, scratch resistance of the protective layer, and adhesiveness. Is to provide an improved image formed product and an image forming method thereof.

The above object of the present invention is achieved by the following configurations.
(Claim 1)
After forming an image by thermal transfer on a thermal transfer image-receiving sheet having an image-receiving layer on a substrate, protective transfer using a thermal transfer sheet provided with a peelable protective transfer layer on at least a part of one surface of the substrate sheet An image formed by using a thermal transfer system for transferring a layer, wherein the electric resistance measured by the salt bridge method of the thermal transfer image-receiving sheet before the protective transfer layer is transferred is from 1 × 10 ⁸ to 1 × 10 ¹² Ω / □, and having the transferred protective transfer layer, and removing the layer coated on the side opposite to the image forming surface, by the salt bridge method on the image receiving surface side of the image forming surface An image-formed product having a measured electric resistance of 1 × 10 ⁸ to 1 × 10 ¹² Ω / □.
(Claim 2)
The image-formed product according to claim 1, wherein the thermal transfer image-receiving sheet has a conductive layer containing a particulate conductive agent on a surface side on which an image is formed.
(Claim 3)
2. The image-formed product according to claim 1, wherein the thermal transfer image-receiving sheet has a conductive layer containing a particulate conductive agent between the image-receiving layer and the substrate.
(Claim 4)
4. The image-formed product according to claim 2, wherein the conductive agent is at least one selected from crystalline metal oxide fine particles, ionic crosslinkable polymer fine particles, and smectite clay mineral fine particles.
(Claim 5)
5. The image formed product according to claim 2, wherein a volume ratio of the conductive fine particles in the conductive layer is 25 to 80%.
(Claim 6)
5. The image formed product according to claim 2, wherein a volume ratio of the conductive fine particles in the conductive layer is 35 to 70%.
(Claim 7)
The image-receiving layer of the thermal transfer image-receiving sheet contains a metal ion-containing compound that reacts with a chelatable heat-diffusible dye diffused from a dye layer provided on the thermal transfer sheet. The image-formed product according to any one of the above.
(Claim 8)
The thermal transfer image-receiving sheet has a layer whose outermost surface is mainly composed of a cellulose-based resin on a surface opposite to a surface on which an image is formed with the substrate interposed therebetween. The image-formed product according to any one of the above.
(Claim 9)
An image forming method for producing the image formed product according to claim 1.

  According to the present invention, an image formed article having improved antistatic effect, transportability against static electricity generation, and separation without deterioration of storage stability, scratch resistance of the protective layer, and adhesiveness, and an image forming method thereof Can be provided.

  Hereinafter, the best mode for carrying out the present invention will be described in detail, but the present invention is not limited thereto.

As a result of intensive studies in view of the above problems, the inventor has an electrical resistance measured by the salt bridge method of the thermal transfer image-receiving sheet before the protective transfer layer is transferred, of 1 × 10 ⁸ to 1 × 10 ¹² Ω / □, and an image formed product having an electric resistance measured by the salt bridge method on the image receiving surface side of the image formed product having a transferred protective transfer layer is 1 × 10 ⁸ to 1 × 10 ¹² Ω / □ In addition, the present inventors have found that an image-formed product having improved antistatic effect, transportability against static electricity generation, and dispersibility can be realized without deteriorating storage stability, scratch resistance of the protective layer, and adhesiveness. It depends on you.

  Details of the present invention will be described below.

  In the image formed product to which the protective layer of the present invention is transferred, the conductive layer is not always located on the surface of the image formed product. It is not an indicator of conductivity. That is, in the current surface resistance measurement value obtained, it is not possible to distinguish whether it itself has no conductivity or cannot be detected. As a result of studying the conductive characteristics of the image-formed product by the present inventor, even if the image-formed product does not exhibit sufficient conductivity in the surface resistance measurement, sufficient conductivity can be obtained in an internal layer other than the surface. If maintained, it was found that the desired antistatic effect was obtained.

  In the present invention, one of the characteristics is that the electrical resistance value measured by the salt bridge method is used as the conductivity measurement of the layer located inside other than the surface layer.

  Examples of the salt bridge method in the present invention include R.I. A. Elder's “Resitivity Measurements on Burried Conductive Layers”, 1990 EOS / ESD Symposium Proceedings, pages 251 to 254, the details of which can be used for salt bridge wet electrode resistivity (WER) measurements. .

  The electrical resistance value measured by the salt bridge method according to the present invention is an electrical resistance value measured by the following method with reference to the above measurement method.

  The thermal transfer image-receiving sheet E before and after the transfer of the protective layer is cut out to 3 cm × 15 cm and conditioned for 12 hours or more in an environment of 23 ° C. and 55%. Moreover, the salt bridge method resistance measuring apparatus shown in FIG. 1 is installed in the same environment. In FIG. 1, a pair of metal electrodes B having depressions A for holding a buffer solution (for example, neutral phosphate pH standard solution (pH = 6.86) manufactured by Toago Denpa Kogyo Co., Ltd.) Installed on the plate C, insert both end portions (3 cm side) of each thermal transfer image-receiving sheet E into the respective depressions A of both electrodes of the apparatus, and apply a voltage (100 V) to the teraohm meter D for 1 minute. The subsequent electrical resistance value is measured.

  In the present invention, the value calculated by the electric resistance value × 3/15 is the electric resistance value measured by the salt bridge method according to the present invention.

In the present invention, the electrical resistance value of the thermal transfer image-receiving sheet before printing measured according to the above method is 1 × 10 ⁸ to 1 × 10 ¹² Ω / □, and the protective layer after forming the printing protective layer is used. The electrical resistance value measured by the salt bridge method on the image-receiving surface side of the image-formed product is 1 × 10 ⁸ to 1 × 10 ¹² Ω / □. By setting the electrical resistance value within the range specified above, it is possible to prevent conveyance troubles due to the generation of static electricity, prevent color loss due to adhesion of dust etc. to the dye receiving layer surface of the thermal transfer image-receiving sheet, and improve separation characteristics. I found it. Here, the electrical resistance measured by the salt bridge method “on the image receiving surface side” of the image-formed product having a protective layer is applied to the surface opposite to the surface on which the image is formed on the substrate. This is an electric resistance value measured by a similar salt bridge method after removing a layer to be formed (for example, a back layer) with a solvent or the like. In the thermal transfer method in which the protective transfer layer is transferred using a heat transfer sheet provided with a peelable protective transfer layer, it is not sufficient to provide conductivity in the back layer, and conductivity is provided on the image receiving surface side. It is important that

<Thermal transfer image-receiving sheet>
The thermal transfer image-receiving sheet according to the present invention has at least one image-receiving layer on a substrate, but in order to achieve the electrical resistance value defined in the present invention, a conductive layer containing a conductive agent may be further provided. preferable.

  FIG. 2 is a schematic sectional view showing an example of the configuration of the thermal transfer image receiving sheet according to the present invention.

  In FIG. 2, the thermal transfer image receiving sheet 1 includes a base sheet 2 and a dye receiving layer 3 on one surface of the base sheet 2. Furthermore, it has the conductive layer 5 containing a conductive agent between the base material sheet 2 and the dye receiving layer 3. Further, a back layer 4 is provided on the surface of the base sheet 2 opposite to the surface on which the dye-receiving layer 3 is provided to provide curl adjustment, abrasion resistance and slipperiness.

  The components of the thermal transfer image receiving sheet according to the present invention will be described sequentially.

[Conductive layer]
First, a conductive layer containing a conductive agent according to the present invention (hereinafter also referred to as an antistatic layer) will be described.

  The means for realizing the electrical resistance value measured by the salt bridge method defined in the present invention is not particularly limited, but in the present invention, the surface of the thermal transfer image-receiving sheet according to the present invention on which the image is formed is particulate. It is preferable to provide a conductive layer containing a conductive agent. This conductive layer may also serve as a dye receiving layer described later, but is preferably formed between the base sheet and the dye receiving layer from the viewpoint of coloring or storage. The conductive layer may also serve as an intermediate layer, may be provided between the base sheet and the intermediate layer, or may be provided between the intermediate layer and the dye receiving layer.

  The type of the conductive agent used in the conductive layer according to the present invention is not particularly limited as long as the electrical resistance value according to the salt bridge method satisfies the conditions specified in the present invention, but in the present invention, an antistatic agent is used. Specific examples include conductive fine particles of crystalline metal oxides, ionic crosslinkable polymer conductive fine particles, and smectite group clay minerals.

Examples of conductive fine particles of crystalline metal oxide used in the present invention include oxygen-excess oxides such as Nb ₂ O ₅ ^{+ x} , oxygen-deficient oxides such as RhO ₂ ^-x and Ir ₂ O ₃ ^-x , Or non-stoichiometric hydroxide such as Ni (OH) _x , HfO ₂ , ThO ₂ , ZrO ₂ , CeO ₂ , ZnO, TiO ₂ , SnO ₂ , Al ₂ O ₃ , In ₂ O ₃ , SiO ₂ , MgO, BaO, MoO ₂ , V ₂ O ₅ or the like or a complex oxide thereof is preferable, and ZnO, TiO ₂ and SnO ₂ are particularly preferable. To obtain a higher conductivity may be doped with foreign atoms, for example, the addition Al, or In to ZnO, for the TiO ₂ Nb, the addition of Ta, etc., also with respect to SnO ₂ Therefore, the addition (doping) of Sb, Nb, halogen elements, etc. is effective. The addition amount (doping amount) of these different atoms is preferably in the range of 0.01 to 25 mol%, particularly preferably in the range of 0.1 to 15 mol%. Of these crystalline metal oxides, antimony-doped tin oxide or niobium-doped titanium oxide is preferably used from the viewpoint of improving conductivity and coloring, and antimony-doped tin oxide is particularly preferable. The average particle size of the conductive metal fine particles of the crystalline metal oxide is preferably 1.0 μm or less, more preferably 0.3 μm or less, and further preferably 0.1 μm or less. preferable. The conductive fine particles of these crystalline metal oxides can be prepared, for example, according to the method described in JP-A-56-143430. In addition, conductive fine particles obtained by coating the above metal oxide on titanium oxide particles or the like can also be preferably used.

  The ionic crosslinkable polymer conductive fine particle is a polymer having a crosslinkable quaternary ammonium group described in JP-B-60-45231, for example, a copolymer [N, N, N-trimethyl-N-vinylbenzyl]. Ammonium chloride-co-divinylbenzene] and a crosslinked ionene polymer described in JP-A-7-28194 can be mentioned, and any of them is useful for the present invention.

  The ionene polymer here is a polymer having an ammonium group in the main chain by a quaternization reaction between a diamine and a compound such as a dichloride that generates an ammonium group, and the crosslinked ionene polymer is an ionene-type unit or polymer. Becomes a cross-linked chain, or another monomer or polymer forms a cross-linked chain and contains an ionene-type moiety. U.S. Pat. Nos. 4,237,174, 4,308,332 and 4,526,706 disclose latex particles stabilized by a cation bound to a polyaniline adduct salt semiconductor. Conductive polymer particles such as those are disclosed and can be usefully used in the present invention. The methods for synthesizing these polymers are described in the above-mentioned specifications, and can be synthesized according to them.

  Smectite group clay minerals include natural montmorillonite, beidellite, nontronite or saponite.In the present invention, these natural minerals can be used without limitation. A synthetic smectite clay mineral that is not a natural product is preferred for the present invention because of increased costs.

  Examples of synthetic smectite group clay minerals useful in the present invention include Laporte Industries, Ltd. of the United Kingdom, US subsidiary SouthernClay Products, Inc. And is marketed under the trade name Laponite. This is a lamellar hydrous magnesium silicate, and suitable monovalent ions, such as magnesium ions partially substituted by lithium, sodium, potassium and / or vacancies, can also be partially replaced by fluorine ions. The center octahedral sheet is formed by coordinating with oxygen and / or hydroxyl ions in an octahedral shape. Such an octahedral sheet is sandwiched between two tetrahedral sheets of silicon ions coordinated in a tetrahedral fashion to oxygen.

  Laponite has many grades such as RD, RDS, J, S, etc., each having its own unique properties, any of which can be used in the present invention as long as it retains conductivity.

  These smectite group clay minerals have various sizes. In the present invention, the average particle size is preferably 0.5 μm or less, particularly preferably 0.2 μm or less.

  The volume ratio of the conductive particles in the conductive layer containing the conductive agent according to the present invention is 25 to 80% by volume, more preferably 35 to 70% by volume. Note that this ratio is important in the thermal transfer method in which the protective transfer layer is transferred using a thermal transfer sheet provided with a protective transfer layer so as to be peelable. Measured by the method), and if it is less than 25% by volume, conductivity may be lost at all. However, in the thermal transfer method in which the protective layer is not transferred, this is not the case, and the continuity of the conductive agent in the conductive layer is destroyed by pressure, heat, etc. during the transfer of the protective layer. Yes. Further, if the volume ratio exceeds 70% by volume, the interlayer adhesion is lowered, and if it exceeds 80% by volume, the interlayer adhesion may be lowered to a level that poses a problem as a product quality.

  In addition, let the volume ratio of the electroconductive particle said by this invention be the value calculated | required by the following Formula.

Volume ratio of conductive particles = conductive particle volume / (conductive particle volume + binder resin volume)
The binder resin used in the conductive layer containing the conductive agent according to the present invention is not particularly limited, and can be selected according to the adhesiveness with the base material to be coated, the physical property value of the target conductive layer, and the like. For example, hydrophilic binders such as gelatin and polyvinyl alcohol may be used, or cellulose resins such as polyvinyl chloride, polyvinyl acetate, ethyl cellulose, hydroxy cellulose, hydroxypropyl cellulose, methyl cellulose, cellulose acetate, cellulose acetate butyrate, and nitrocellulose. , Polyurethane resin, acrylic resin, epoxy group-containing acrylic acid resin, urethane acrylate resin, polyester resin and other thermoplastic resins dissolved in an organic solvent or the like, or an aqueous dispersion containing these binder resin particles May be used.

  Moreover, hardening agents, such as isocyanate, can also be utilized with these binder resins.

[Base material sheet]
The substrate sheet used in the thermal transfer image-receiving sheet has a role of holding the dye image-receiving layer, and since heat is applied during thermal transfer, it preferably has a mechanical strength that does not hinder handling even in an overheated state. .

  There are no particular limitations on the material of such a base material. For example, condenser paper, glassine paper, sulfuric acid paper, high-size paper, synthetic paper (polyolefin-based, polystyrene-based), high-quality paper, art paper, coated paper , Cast coated paper, wallpaper, backing paper, synthetic resin or emulsion impregnated paper, synthetic rubber latex impregnated paper, synthetic resin internal paper, paperboard, cellulose fiber paper, or polyester, polyacrylate, polycarbonate, polyurethane, polyimide, polyether Imide, cellulose derivative, polyethylene, ethylene-vinyl acetate copolymer, polypropylene, polystyrene, acrylic, polyvinyl chloride, polyvinylidene chloride, polyvinyl alcohol, polyvinyl butyral, nylon, polyether ether ketone, polysulfone, Examples include polyethersulfone, tetrafluoroethylene, perfluoroalkyl vinyl ether, polyvinyl fluoride, tetrafluoroethylene / ethylene, tetrafluoroethylene / hexafluoropropylene, polychlorotrifluoroethylene, and polyvinylidene fluoride. A white opaque film formed by adding a white pigment or a filler to these synthetic resins or a foamed foam sheet can be used, and is not particularly limited.

  Moreover, the laminated body by the arbitrary combinations of the said base material can also be used. Examples of typical laminates include cellulose fiber paper and synthetic paper, or synthetic paper of cellulose synthetic paper and a plastic film. The thickness of these substrate sheets may be arbitrary and is usually about 10 to 300 μm.

  In order to obtain higher printing sensitivity and high image quality without density unevenness or white spots, it is preferable to have a layer having fine voids. As the layer having fine voids, a plastic film or synthetic paper having fine voids inside can be used. Moreover, the layer which has a fine space | gap by various coating systems can be formed on various base material sheets. As a plastic film or synthetic paper having fine voids, polyolefin, especially polypropylene, is mainly blended with an inorganic pigment and / or a polymer incompatible with polypropylene, and these are used as void (void) formation initiators. A plastic film or synthetic paper obtained by stretching and forming a mixture of the above is preferable. If these are mainly polyester, etc., the viscoelastic or thermal properties make the cushioning and heat insulation properties inferior to those mainly made of polypropylene. Unevenness is also likely to occur.

Considering these points, the elastic modulus at 20 ° C. of the plastic film and synthetic paper is preferably 5 × 10 ⁸ Pa to 1 × 10 ¹⁰ Pa. In addition, since these plastic films and synthetic paper are usually formed by biaxial stretching, they shrink by heating. When these are left at 110 ° C. for 60 seconds, the shrinkage is 0.5 to 2.5%. The plastic film and the synthetic paper described above may be combined with each other as a single layer including fine voids, or may have a plurality of layers. In the case of a plurality of layer configurations, all layers constituting the layer may contain fine voids, or a layer having no fine voids may be contained. A white pigment may be mixed in the plastic film or synthetic paper as a concealing agent as necessary. In order to increase whiteness, an additive such as a fluorescent brightening agent may be included. The layer having fine voids preferably has a thickness of 30 to 80 μm.

  As a layer having fine voids, a layer having fine voids can be formed on a substrate by a coating method. As the plastic resin to be used, known resins such as polyester, urethane resin, polycarbonate, acrylic resin, polyvinyl chloride, and polyvinyl acetate can be used singly or in combination.

Further, if necessary, a resin such as polyvinyl alcohol, polyvinylidene chloride, polyethylene, polypropylene, modified polyolefin, polyethylene terephthalate, polycarbonate, or the like is provided on the surface of the substrate opposite to the side on which the image receiving layer is provided for the purpose of preventing curling. Or a layer of synthetic paper. As a bonding method, for example, known lamination methods such as dry lamination, non-solvent (hot melt) lamination, EC lamination method and the like can be used, but preferred methods are dry lamination and non-solvent lamination. Examples of the adhesive suitable for the non-solvent lamination method include Takenate 720L manufactured by Takeda Pharmaceutical Co., Ltd., and examples of the adhesive suitable for dry lamination include Takelac manufactured by Takeda Pharmaceutical Co., Ltd. Examples include A969 / Takenate A-5 (3/1), Polysol PSA SE-1400, Vinylol PSA AV-6200 series, manufactured by Showa High Polymer Co., Ltd., and the like. The amount of these adhesives, from about 1-8 g / m ² on a solids, and preferably from 2 to 6 g / m ^2.

  When a plastic film and synthetic paper as described above, or between them, or various types of paper and plastic film or synthetic paper are laminated, they can be bonded together by an adhesive layer.

  For the purpose of increasing the adhesive strength between the substrate sheet and the dye-receiving layer, it is preferable to subject the surface of the substrate sheet to various primer treatments and corona discharge treatments.

(Dye-receiving layer)
The dye receiving layer provided on the thermal transfer image receiving sheet is for receiving the sublimable dye moving from the thermal transfer sheet and maintaining the formed image.

<Binder resin>
Binder resins for forming the dye-receiving layer include polyolefin resins such as polypropylene, halogenated resins such as polyvinyl chloride and polyvinylidene chloride, vinyl resins such as polyvinyl acetate and polyacrylate, polyethylene terephthalate, poly Polyester resins such as butylene terephthalate, polystyrene resins, polyamide resins, phenoxy resins, copolymers of olefins such as ethylene and propylene with other vinyl monomers, polyurethane, polycarbonate, acrylic resins, ionomers, cellulose derivatives, etc. Alternatively, a polyester resin, a vinyl resin, and a cellulose derivative are preferable among these.

<Release agent>
It is preferable to add a release agent to the dye receiving layer according to the present invention for the purpose of preventing thermal fusion with the dye layer. As the mold release agent, a phosphoric ester plasticizer, a fluorine compound, silicone oil (including reaction curable silicone) and the like can be used, and among these, silicone oil is preferable. As the silicone oil, various modified silicones including dimethyl silicone can be used. Specifically, amino-modified silicones, epoxy-modified silicones, alcohol-modified silicones, vinyl-modified silicones, urethane-modified silicones, and the like can be blended or polymerized using various reactions. The release agent may be used alone or in combination of two or more. Further, the addition amount of the release agent is preferably 0.5 to 30 parts by mass with respect to 100 parts by mass of the binder resin for forming the dye image-receiving layer. When the range of the addition amount is not satisfied, there may be a problem such as fusion between the thermal transfer sheet and the dye image-receiving layer of the thermal transfer image-receiving sheet or a decrease in printing sensitivity. In addition, you may provide these mold release agents as a mold release layer separately on a dye receiving layer, without adding to a dye image receiving layer.

<Metal ion-containing compound>
The dye-receiving layer according to the present invention preferably contains a metal ion-containing compound (hereinafter also referred to as a metal source).

Examples of the metal source include inorganic or organic salts and metal complexes of metal ions, and among them, salts and complexes of organic acids are preferable. Examples of the metal include monovalent 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 preferable, and Ni, Cu, Cr, Co and Zn are particularly preferable. Specific examples of the metal source include Ni ²⁺ , Cu ²⁺ , Cr ²⁺ , Co ²⁺ and Zn ²⁺ and aliphatic salts such as acetic acid and stearic acid, or aromatic carboxylic acids such as benzoic acid and salicylic acid. Examples include acid salts.

  In the present invention, the metal source is particularly preferably a complex represented by the following general formula (I) because it can be stably added to the binder resin in the post-heating region and is substantially colorless.

Formula (I)
[M (Q ₁ ) _X (Q ₂ ) _Y (Q ₃ ) _Z ] ^{P +} (L ⁻ ) _P
In the above general formula (1), M represents a metal ion, preferably Ni ²⁺ , Cu ²⁺ , Cr ²⁺ , Co ²⁺ or Zn ²⁺ . Q ₁ , Q _2, and Q ₃ each represent a coordination compound that can be coordinated to a metal ion represented by M, and may be the same or different from each other. These coordination compounds can be selected from, for example, coordination compounds described in Chelate Science (5) (Nan Edo). L ^- represents an organic anion group, and specific examples include tetraphenyl boron anion and alkylbenzene sulfonate anion. X represents 1, 2 or 3, Y represents 1, 2 or 0, and Z represents 1 or 0. P represents 1 or 2. Specific examples of this type of metal source include compounds exemplified in U.S. Pat. No. 4,987,049 or compound No. 9 exemplified in JP-A-9-39423. 1-99 etc. can be mentioned. Particularly preferred is a compound represented by the following general formula (II) described in JP-A-10-241410.

Formula (II)
M ²⁺ (X ₁ ^-) ₂
In the general formula (II), M ²⁺ represents a divalent transition metal ion, and among these, nickel and zinc are preferred from the color of the metal ion supply compound itself and the color tone of the chelated dye. X ₁ ^- represents a coordination compound capable of forming divalent metal ions and complexes. These compounds may have a neutral ligand depending on the central metal, and typical ligands include H ₂ O and NH ₃ .

[Middle layer]
Further, in the thermal transfer image receiving sheet, an intermediate layer may be provided between the base sheet and the dye receiving layer in addition to the electric transmission according to the present invention. Examples of the function of the intermediate layer include solvent resistance performance, barrier performance, adhesion performance, white color imparting performance, hiding performance, and the like, but not limited to these, all conventionally known intermediate layers can be applied.

  In order to impart solvent resistance and barrier performance to the intermediate layer, it is preferable to use a water-soluble resin. Examples of water-soluble resins include cellulose resins such as carboxymethylcellulose, polysaccharide resins such as starch, proteins such as casein, gelatin, agar, and polyvinyl alcohol, ethylene vinyl acetate copolymer, polyvinyl acetate, vinyl chloride, Vinyl-based resins such as vinyl acetate copolymers (for example, Veopa manufactured by Japan Epoxy Resin Co., Ltd.), vinyl acetate (meth) acrylic copolymers, (meth) acrylic resins, styrene (meth) acrylic copolymers, and styrene resins. In addition, polyamide resins such as melamine resin, urea resin and benzoguanamine resin, polyester, polyurethane and the like can be mentioned. The water-soluble resin referred to here is completely dissolved (particle size of 0.01 μm or less), colloidal dispersion (0.01 to 0.1 μm), or emulsion (0.1 to 1 μm) in a solvent mainly composed of water. ) Or a resin in a slurry (1 μm or more) state. Of these water-soluble resins, particularly preferred are alcohols such as methanol, ethanol, and isopropyl alcohol, and dissolution with general-purpose solvents such as hexane, cyclohexane, acetone, methyl ethyl ketone, xylene, ethyl acetate, butyl acetate, and toluene. Of course, it is a resin that does not even swell. In this sense, a resin that is completely soluble in a solvent mainly composed of water is most preferable. In particular, a polyvinyl alcohol resin and a cellulose resin are mentioned.

  In order to give adhesive performance to the intermediate layer, a urethane-based resin and a polyolefin-based resin are generally used depending on the type of the base sheet and its surface treatment. Further, when a thermoplastic resin having active hydrogen and a curing agent such as an isocyanate compound are used in combination, good adhesiveness can be obtained. In order to give the intermediate layer a white color imparting ability, a fluorescent whitening agent can be used. The optical brightener used can be any conventionally known compound, including stilbene, distilbene, benzoxazole, styryl-oxazole, pyrene-oxazole, coumarin, aminocoumarin, imidazole, and benzimidazole. -Based, pyrazoline-based, and distyryl-biphenyl-based fluorescent whitening agents. The whiteness can be adjusted by the type and amount of the fluorescent brightener. Any method can be used as the method of adding the optical brightener. That is, a method of adding by dissolving in water, a method of adding by pulverizing and dispersing by a ball mill or a colloid mill, a method of dissolving in a high boiling point solvent and mixing with a hydrophilic colloid solution, and adding as an oil-in-water dispersion, There is a method of impregnating the polymer latex and adding it.

  Further, titanium oxide may be added to the intermediate layer in order to conceal the glaring feeling and unevenness of the base sheet. Furthermore, the use of titanium oxide is preferable in that the degree of freedom in selecting a base sheet is widened. There are two types of titanium oxide: rutile type titanium oxide and anatase type titanium oxide, but considering the effect of whiteness and fluorescent brightening agent, the absorption in the ultraviolet region is shorter than rutile type. Anatase type titanium oxide is preferred. If the binder resin in the intermediate layer is aqueous and titanium oxide is difficult to disperse, use titanium oxide with a hydrophilic treatment on the surface, or disperse it with a known dispersant such as a surfactant or ethylene glycol. be able to. As for the addition amount of a titanium oxide, 10-400 mass parts is preferable as a titanium oxide solid content with respect to 100 mass parts of resin solid content.

[Back layer]
The back layer may have a multilayer structure in which a plurality of layers are laminated, but the main component of the binder of the outermost layer is ethyl cellulose, hydroxy cellulose, hydroxypropyl cellulose, methyl cellulose, cellulose acetate, cellulose acetate butyrate, nitrocellulose, etc. A cellulose resin is preferred. By combining this with the conductivity defined by the salt bridge method, the antistatic performance such as sagability is further improved. Although the details are unknown, it is presumed that the charged series of the cellulosic resin is in a relatively intermediate position and the generation of charges is relatively reduced. The back layer may contain a conventionally known additive such as a conductive agent and a matting agent.

<Thermal transfer sheet>
The thermal transfer sheet according to the present invention has each dye layer containing a dye and a peelable protective transfer layer.

  FIG. 3 is a perspective view showing an example of a mode in which one surface of the thermal transfer sheet according to the present invention is sequentially supplied. In FIG. 3, the thermal transfer sheet 11 is formed with dye layers 13Y, 13M, and 13C corresponding to yellow (Y), magenta (M), and cyan (C) dyes on the same plane of the base sheet 12. In addition, a protective transfer layer unit 14 including a peelable protective transfer layer is provided in an area different from the dye layer in the surface order. The protective transfer layer unit 14 is configured on a base sheet 12 in the order of a non-transferable release layer 15, a protective transfer layer 16, and an adhesive layer 17. The other surface of the base sheet 2 is provided with a heat-resistant slip layer 18. The protective transfer layer 16 may be a laminate of a protective layer and an adhesive layer.

In FIG. 3, there are slight gaps between the dye layers or the protective transfer layer unit 14, but the gaps may be appropriately adjusted in accordance with the control method of the thermal transfer recording apparatus. Further, in order to increase the accuracy of cueing each dye layer, it is preferable to provide a detection mark on the thermal transfer sheet, and there is no particular limitation on how to provide the detection mark. Although a dye layer and a heat transferable protective transfer layer or a region where post-heating treatment is performed are shown on the same plane of the base sheet, of course, each layer may be provided on a separate support. Needless to say. In addition, when a reactive dye is used for each dye layer, the dye itself contained in the dye layer is a compound before the reaction, and strictly speaking, it cannot be said to be Y, M, or C dye, but Y, M In the sense that it is the layer for finally forming the C image, it is expressed in the same way for convenience. [Base material sheet]
As the base sheet used in the thermal transfer sheet according to the present invention, conventionally known materials can be used as the base sheet of the thermal transfer sheet. Specific examples of preferred substrate sheets are thin papers such as glassine paper, condenser paper, paraffin paper, polyethylene terephthalate, polyethylene naphthalate, polybutylene terephthalate, polyphenylene sulfide, polyether ketone, polyether sulfone and other high heat resistant polyesters. Polypropylene, fluororesin, polycarbonate, cellulose acetate, polyethylene derivatives, polyvinyl chloride, polyvinylidene chloride, polystyrene, polyamide, polyimide, polymethylpentene, ionomer, etc. The thing which was done is mentioned. The thickness of the base sheet can be appropriately selected depending on the material so that the strength, heat resistance and the like are appropriate, but usually a thickness of about 1 to 100 μm is preferably used.

  Moreover, when adhesion with the dye layer formed on the surface of the substrate sheet is poor, it is preferable to perform primer treatment or corona treatment on the surface.

[Dye layer]
The dye layer constituting the thermal transfer sheet according to the present invention is a heat sublimable colorant layer containing at least a dye and a binder resin.

<dye>
The dye-containing region used in the thermal transfer sheet according to the present invention can be two or more dye-containing regions having different hues. For example, the dye-containing region includes a yellow dye-containing region, a magenta dye-containing region, and cyan. An embodiment in which a dye-containing region is formed after the dye-containing region, and the dye-containing region is an ink layer containing a black dye, and the dye-free region is next to the region. The formed embodiment and the dye-containing region are composed of a region containing a yellow dye, a region containing a magenta dye, a region containing a cyan dye, and a region containing a black dye. The aspect etc. in which the containing area | region was formed are mentioned.

  Examples of the dye used in the heat sublimable colorant layer include all dyes such as azo, azomethine, methine, anthraquinone, quinophthalone, and naphthoquinone that are used in a heat transfer sheet of a conventional heat-sensitive sublimation transfer method. There is no particular limitation. Specific examples of yellow dyes include Holon Brilliant Yellow 6GL, PTY-52, Macrolex Yellow 6G, and red dyes such as MS Red G, Macrolex Red Violet R, Ceres Red 7B, Samaron Red HBSL, and SK. Rubin SEGL and the like, and as blue dyes, Kayaset Blue 714, Waxoline Blue AP-FW, Holon Brilliant Blue S-R, MS Blue 100, Daito Blue No. 1 etc. are mentioned.

  The heat-diffusible dye capable of forming a chelate is not particularly limited as long as thermal transfer is possible, and various known compounds can be appropriately selected and used. For example, JP-A-59-78893 The cyan dyes, magenta dyes, yellow dyes and the like described in JP-A No. 59-109349, JP-A-4-94974, JP-A-4-97894, and Patent No. 2,856,225 are used. can do.

  For example, examples of the chelate cyan dye include compounds represented by the following general formula (1).

In the general formula (1), R ₁₁ and R ₁₂ each represents a substituted or unsubstituted aliphatic group, and R ₁₁ and R 12 may be the same or different. Examples of the aliphatic group include an alkyl group, a cycloalkyl group, an alkenyl group, and an alkynyl group. Examples of the alkyl group include a methyl group, an ethyl group, a propyl group, and an i-propyl group. Examples of a group that can replace these alkyl groups include a linear or branched alkyl group (for example, a methyl group). Group, ethyl group, i-propyl group, t-butyl group, n-dodecyl group, 1-hexylnonyl group, etc.), cycloalkyl group (for example, cyclopropyl group, cyclohexyl group, bicyclo [2.2.1]) Heptyl group, adamantyl group and the like), alkenyl group (for example, 2-propylene group, oleyl group, etc.), aryl group (for example, phenyl group, ortho-tolyl group, ortho-anisyl group, 1-naphthyl group, 9- Anthranyl group, etc.), heterocyclic group (for example, 2-tetrahydrofuryl group, 2-thiophenyl group, 4-imidazolyl group, 2-pyridyl group, etc.) Halogen atom (eg, fluorine atom, chlorine atom, bromine atom), cyano group, nitro group, hydroxy group, carbonyl group (eg, alkylcarbonyl group such as acetyl group, trifluoroacetyl group, pivaloyl group, benzoyl group, pentane) Fluorobenzoyl group, arylcarbonyl group such as 3,5-di-t-butyl-4-hydroxybenzoyl group), oxycarbonyl group (for example, methoxycarbonyl group, cyclohexyloxycarbonyl group, n-dodecyloxycarbonyl group, etc.) Aryloxycarbonyl groups such as alkoxycarbonyl group, phenoxycarbonyl group, 2,4-di-t-amylphenoxycarbonyl group, 1-naphthyloxycarbonyl group, 2-pyridyloxycarbonyl group, 1-phenylpyrazolyl-5-oxy Carbonyl Heterocyclic oxycarbonyl groups, etc.), carbamoyl groups (for example, dimethylcarbamoyl groups, 4- (2,4-di-t-amylphenoxy) butylaminocarbonyl groups and other alkylcarbamoyl groups, phenylcarbamoyl groups, 1-naphthyl Arylcarbamoyl group such as carbamoyl group), alkoxy group (for example, methoxy group, 2-ethoxyethoxy group, etc.), aryloxy group (for example, phenoxy group, 2,4-di-t-amylphenoxy group, 4- (4 -Hydroxyphenylsulfonyl) phenoxy group), heterocyclic oxy group (for example, 4-pyridyloxy group, 2-hexahydropyranyloxy group, etc.), carbonyloxy group (for example, acetyloxy group, trifluoroacetyloxy group, Alkylcarbonyloxy groups such as pivaloyloxy group, Zoyloxy group, aryloxy group such as pentafluorobenzoyloxy group), urethane group (for example, alkylurethane group such as N, N-dimethylurethane group, N-phenylurethane group, N- (p-cyanophenyl) urethane group Aryl urethane groups, etc.), sulfonyloxy groups (for example, methanesulfonyloxy groups, trifluoromethanesulfonyloxy groups, alkylsulfonyloxy groups such as n-dodecanesulfonyloxy groups, benzenesulfonyloxy groups, p-toluenesulfonyloxy groups, etc.) An arylsulfonyl group such as a dimethylamino group, a cyclohexylamino group, an alkylamino group such as an n-dodecylamino group, an anilino group, an arylamino group such as a pt-octylanilino group, etc.) , Sulfonylamino group ( For example, methanesulfonylamino group, heptafluoropropanesulfonylamino group, alkylsulfonylamino group such as n-hexadecylsulfonylamino group, p-toluenesulfonylamino group, arylsulfonylamino group such as pentafluorobenzenesulfonylamino), Famoylamino group (for example, alkylsulfamoylamino group such as N, N-dimethylsulfamoylamino group, arylsulfamoylamino group such as N-phenylsulfamoylamino group), acylamino group (for example, Alkylcarbonylamino group such as acetylamino group, myristoylamino group, arylcarbonylamino group such as benzoylamino group, etc., ureido group (for example, alkylureido group such as N, N-dimethylaminoureido group, N-phenylurea, etc.) Group, arylureido groups such as N- (p-cyanophenyl) ureido group), sulfonyl groups (eg, alkylsulfonyl groups such as methanesulfonyl group and trifluoromethanesulfonyl group, arylsulfonyl groups such as p-toluenesulfonyl group) ), Sulfamoyl groups (for example, dimethylsulfamoyl groups, alkylsulfamoyl groups such as 4- (2,4-di-t-amylphenoxy) butylaminosulfonyl group, arylsulfamo groups such as phenylsulfamoyl group) Moyl group etc.), alkylthio group (eg methylthio group, t-octylthio group etc.), arylthio group (eg phenylthio group etc.), heterocyclic thio group (eg 1-phenyltetrazole-5-thio group, 5-methyl) -1,3,4-oxadiazol-2-thio group and the like.

  Examples of the cycloalkyl group and the alkenyl group are the same as the above substituents. Examples of the alkynyl group include 1-propyne, 2-butyne, 1-hexyne and the like.

As R ₁₁ and R ₁₂ , a group that forms a non-aromatic cyclic structure (eg, pyrrolidine ring, piperidine ring, morpholine ring, etc.) is also preferable.

R ₁₃ is preferably an alkyl group, a cycloalkyl group, an alkoxy group, or an acylamino group among the above substituents. n represents an integer of 0 to 4, and when n is 2 or more, the plurality of R ₁₃ may be the same or different.

R ₁₄ is an alkyl group, and examples thereof include a methyl group, an ethyl group, an i-propyl group, a t-butyl group, an n-dodecyl group, and a 1-hexylnonyl group. R ₁₄ is preferably a secondary or tertiary alkyl group, and examples of a preferable secondary or tertiary alkyl group include an isopropyl group, a sec-butyl group, a tert-butyl group, and a 3-heptyl group. The most preferred substituent for R ₁₄ is an isopropyl group or a tert-butyl group. The alkyl group of R ₁₄ may be substituted, but is all substituted with a substituent consisting of a carbon atom and a hydrogen atom. They are not substituted with substituents containing other atoms.

R ₁₅ is an alkyl group, and examples thereof include an n-propyl group, i-propyl group, t-butyl group, n-dodecyl group, 1-hexylnonyl group and the like. R ₁₅ is preferably a secondary or tertiary alkyl group, and preferred examples of the secondary or tertiary alkyl group include an isopropyl group, a sec-butyl group, a tert-butyl group, and a 3-heptyl group. The most preferred substituent for R ₁₅ is an isopropyl group or a tert-butyl group. The alkyl group for R ₁₅ may be substituted, but is all substituted with a substituent consisting of a carbon atom and a hydrogen atom. They are not substituted with substituents containing other atoms.

R ₁₆ represents an alkyl group, and examples thereof include n-propyl group, n-butyl group, n-pentyl group, n-hexyl group, n-heptyl group, isopropyl group, sec-butyl group, tert-butyl group. , 3-heptyl group and the like. Particularly preferred substituents for R ₁₆ are straight-chain alkyl groups having 3 or more carbon atoms, such as n-propyl, n-butyl, n-pentyl, n-hexyl, n-heptyl. And most preferably an n-propyl group or an n-butyl group. The alkyl group represented by R ₁₆ may be substituted, but is all substituted with a substituent consisting of a carbon atom and a hydrogen atom, and is not substituted with a substituent containing other atoms.

  Moreover, as a chelate yellow pigment | dye, the compound represented by following General formula (2) can be mentioned.

In the general formula (2), examples of each substituent represented by R ₁ and R ₂ include a halogen atom, an alkyl group (an alkyl group having 1 to 12 carbon atoms, an oxygen atom, a nitrogen atom, a sulfur atom). Alternatively, a substituent linked by a carbonyl group may be substituted, or an aryl group, alkenyl group, alkynyl group, hydroxyl group, amino group, nitro group, carboxyl group, cyano group or halogen atom may be substituted. Methyl, isopropyl, t-butyl, trifluoromethyl, methoxymethyl, 2-methanesulfonylethyl, 2-methanesulfonamidoethyl, cyclohexyl, etc.), aryl groups (for example, phenyl, 4-t-butylphenyl, 3 -Groups such as nitrophenyl, 3-acylaminophenyl, 2-methoxyphenyl), cyano group, a Lucoxyl group, aryloxy group, acylamino group, anilino group, ureido group, sulfamoylamino group, alkylthio group, arylthio group, alkoxycarbonylamino group, sulfonamido group, carbamoyl group, sulfamoyl group, sulfonyl group, alkoxycarbonyl group, Examples include a heterocyclic oxy group, an acyloxy group, a carbamoyloxy group, a silyloxy group, an aryloxycarbonylamino group, an imide group, a heterocyclic thio group, a phosphonyl group, and an acyl group.

Examples of the alkyl group and aryl group represented by R ₃ include the same alkyl groups and aryl groups represented by R ₁ and R ₂ .

Specific examples of the 5- to 6-membered aromatic ring constituted with two carbon atoms represented by Z ₁ include benzene, pyridine, pyrimidine, triazine, pyrazine, pyridazine, pyrrole, furan, thiophene and pyrazole. , Imidazole, triazole, oxazole, thiazole and the like, and these rings may further form a condensed ring with other aromatic rings. These rings may have a substituent, and examples of the substituent include the same substituents represented by R ₁ and R ₂ .

  Moreover, as a chelate magenta pigment | dye, the compound represented by following General formula (3) can be mentioned.

In the general formula (3), X represents at least a bidentate chelate-forming group or group of atoms, and Y represents a group of atoms forming a 5-membered or 6-membered aromatic hydrocarbon ring or heterocycle. , R ¹ and R ² each represent a hydrogen atom, a halogen atom or a monovalent substituent. n represents 0, 1, 2;

  X is particularly preferably a group represented by the following general formula (4).

In the general formula (4), Z ₂ represents an atomic group necessary for forming an aromatic nitrogen-containing heterocyclic ring substituted with at least one group containing a chelatable nitrogen atom. Specific examples of the ring include pyridine, pyrimidine, thiazole, imidazole and the like. These rings may further form a condensed ring with another carbocycle (such as a benzene ring) or a heterocycle (such as a pyridine ring).

  In the general formula (3), Y represents a group of atoms forming a 5-membered or 6-membered aromatic hydrocarbon ring or heterocyclic ring, and the ring may further have a substituent, and is condensed. You may have a ring. Specific examples of the ring include 3H-pyrrole ring, oxazole ring, imidazole ring, thiazole ring, 3H-pyrrolidine ring, oxazolidine ring, imidazolidine ring, thiazolidine ring, 3H-indole ring, benzoxazole ring, benzimidazole ring, A benzothiazole ring, a quinoline ring, a pyridine ring, etc. are mentioned. These rings may form a condensed ring with another carbocyclic ring (for example, benzene ring) or a heterocyclic ring (for example, pyridine ring). Examples of substituents on the ring include alkyl groups, aryl groups, heterocyclic groups, acyl groups, amino groups, nitro groups, cyano groups, acylamino groups, alkoxy groups, hydroxy groups, alkoxycarbonyl groups, halogen atoms, etc. The group may be further substituted.

R ¹ and R ² each represent a hydrogen atom, a halogen atom (for example, a fluorine atom, a chlorine atom) or a monovalent substituent, and examples of the monovalent substituent include an alkyl group, an alkoxy group, a cyano group, Examples thereof include an alkoxycarbonyl group, an aryl group, a heterocyclic group, a carbamoyl group, a hydroxy group, an acyl group, and an acylamino group.

  X represents at least a bidentate chelating group or a group of atoms, and may be any compound capable of forming a dye as the general formula (3), for example, 5-pyrazolone, imidazole, pyrazolopyrrole, pyrazolopyrazole, pyra Zoloimidazole, pyrazolotriazole, pyrazolotetrazole, barbituric acid, thiobarbituric acid, rhodanine, hydantoin, thiohydantoin, oxazolone, isoxazolone, indandione, pyrazolidinedione, oxazolidinedione, hydroxypyridone, or pyrazolopyridone are preferred .

<Binder resin>
The dye layer according to the present invention contains a binder resin together with the dye.

  As the binder resin used in the dye layer, a binder resin used in a conventionally known heat-sensitive sublimation transfer type thermal transfer sheet can be used, for example, a cellulose-based resin such as a cellulose addition compound, cellulose ester, cellulose ether, Polyvinyl acetal resins such as polyvinyl alcohol, polyvinyl formal, polyvinyl acetoacetal, polyvinyl butyral, polyvinyl pyrrolidone, polyvinyl acetate, polyacrylamide, styrene resin, poly (meth) acrylic acid ester, poly (meth) acrylic acid, (meth ) Vinyl resins such as acrylic acid copolymers, rubber resins, ionomer resins, olefin resins, polyester resins and the like. Among these resins, polyvinyl butyral, polyvinyl acetoacetal or cellulose resin having excellent storage stability is preferable.

  As a binder resin for the dye layer, a reaction product of an isocyanate described in JP-B-5-78437 and a compound having active hydrogen selected from polyvinyl butyral, polyvinyl formal, polyester polyol and acrylic polyol, isocyan The reaction product in which the amount of the reaction product is 10 to 200 parts by weight with respect to 100 parts by weight of the reaction product in which the narate is diisocyanate or triisocyanate and the compound having active hydrogen; An organic solvent-soluble polymer obtained by esterifying and / or urinating an intramolecular hydroxyl group of a synthetic water-soluble polymer, a natural and / or semi-synthetic water-soluble polymer; the degree of acetylation described in JP-A-3-264393 is 2. Cellulose acetate having a degree of substitution of 4 or more and a total substitution degree of 2.7 or more; polyvinyl alcohol (Tg = 85 ), Polyvinyl acetate (Tg = 32 ° C.), vinyl resin such as vinyl chloride / vinyl acetate copolymer (Tg = 77 ° C.), polyvinyl butyral (Tg = 84 ° C.), polyvinyl acetoacetal (Tg = 110 ° C.), etc. Polyvinyl acetal resins, vinyl resins such as polyacrylamide (Tg = 165 ° C.), polyester resins such as aliphatic polyester (Tg = 130 ° C.), and the like; and isocyanates described in JP-A-7-52564 A reaction product with polyvinyl butyral in which the mass of the vinyl alcohol moiety is 15 to 40%, the reaction product in which the isocyanate is a diisocyanate or a triisocyanate; a general one described in JP-A-7-32742 Phenyl isocyanate-modified polyvinyl acetal resin of formula (I); JP-A-6-155935 One of the isocyanate-reactive cellulose or isocyanate-reactive acetal resins listed above, an isocyanate-reactive acetal resin, an isocyanate-reactive vinyl resin, an isocyanate-reactive acrylic resin, an isocyanate-reactive phenoxy resin, and an isocyanate reaction Cured product of a composition containing one kind of resin selected from a basic polystyrene resin and a polyisocyanate compound; polyvinyl butyral resin (preferably having a molecular weight of 60,000 or more, glass transition temperature of 60 ° C. or more, more preferably 70 ° C. or more) 110 ° C. or less, and the vinyl alcohol moiety has a mass percentage of 10 to 40%, preferably 15 to 30% in the polyvinyl butyral resin); acrylic modified cellulose resin, cellulose resin include ethyl cellulose, hydroxyethyl cellulose, ethyl hydride Cellulose resins (preferably ethyl cellulose) such as loxycellulose, hydroxypropylcellulose, methylcellulose, cellulose acetate and cellulose butyrate can be used.

  One of these various binder resins can be used alone, or two or more thereof can be used in combination.

  Further, the dye layer according to the present invention may contain various known additives as required in addition to the above-described dye and binder resin. The dye layer is prepared by, for example, applying an ink coating solution prepared by dissolving or dispersing the above-mentioned dye, binder resin, or other additive in an appropriate solvent on a base sheet by a known means such as a gravure coating method. Then, it can be formed by drying. The thickness of the dye layer according to the present invention can be about 0.1 to 3.0 μm, preferably about 0.3 to 1.5 μm.

(Protective transfer layer)
One feature of the thermal transfer sheet according to the present invention is that it includes a peelable protective transfer layer. The peelable protective transfer layer is a protective layer that covers the surface of the image formed by thermal transfer on the image receiving sheet, and is mainly composed of a transparent resin layer.

  Examples of the resin forming the protective transfer layer include polyester resins, polystyrene resins, acrylic resins, polyurethane resins, acrylic urethane resins, polycarbonate resins, epoxy-modified resins of these resins, resins obtained by modifying these resins with silicone, Examples thereof include a mixture of these resins, an ionizing radiation curable resin, and an ultraviolet blocking resin. Preferred resins include polyester resins, polycarbonate resins, epoxy-modified resins, and ionizing radiation curable resins. As the polyester resin, an alicyclic polyester resin in which the diol component and the acid component have one or more alicyclic compounds is preferable. As the polycarbonate resin, an aromatic polycarbonate resin is preferable, and an aromatic polycarbonate resin described in JP-A No. 11-151867 is particularly preferable.

  Examples of the epoxy-modified resin used in the present invention include epoxy-modified urethane, epoxy-modified polyethylene, epoxy-modified polyethylene terephthalate, epoxy-modified polyphenyl sulfite, epoxy-modified cellulose, epoxy-modified polypropylene, epoxy-modified polyvinyl chloride, epoxy-modified polycarbonate, Epoxy modified acrylic, epoxy modified polystyrene, epoxy modified polymethyl methacrylate, epoxy modified silicone, copolymer of epoxy modified polystyrene and epoxy modified polymethyl methacrylate, copolymer of epoxy modified acrylic and epoxy modified polystyrene, epoxy modified acrylic and epoxy modified Examples include silicone copolymers, preferably epoxy-modified acrylic, epoxy-modified polystyrene, and epoxy-modified polymers. Methacrylate and epoxy-modified silicone, more preferably a copolymer of epoxy-modified polystyrene and epoxy-modified polymethyl methacrylate, a copolymer of epoxy-modified acrylic and epoxy-modified polystyrene, and a copolymer of epoxy-modified acrylic and epoxy-modified silicone. .

<Ionizing radiation curable resin>
An ionizing radiation curable resin can be used as the protective transfer layer, and the plasticizer resistance and scratch resistance are particularly excellent. As the ionizing radiation curable resin, known ones can be used. For example, a radically polymerizable polymer or oligomer is crosslinked and cured by irradiation with ionizing radiation, and a photopolymerization initiator is added if necessary, and an electron beam is added. Those obtained by polymerization and crosslinking with ultraviolet rays can be used.

<UV blocking resin>
The main purpose of the protective transfer layer containing the ultraviolet blocking resin is to impart light resistance to the printed material. As the ultraviolet blocking resin, for example, a resin obtained by reacting and bonding a reactive ultraviolet absorber to a thermoplastic resin or the above ionizing radiation curable resin can be used. More specifically, a conventionally known non-reactive organic ultraviolet absorber such as salicylate, benzophenone, benzotriazole, substituted acrylonitrile, nickel chelate or hindered amine is added to an addition polymerizable double bond ( Examples thereof include those in which a reactive group such as a vinyl group, an acryloyl group, a methacryloyl group), an alcoholic hydroxyl group, an amino group, a carboxyl group, an epoxy group, or an isocyanate group is introduced.

  In the present invention, as a method for forming a protective transfer layer on a substrate sheet, a coating solution in which additives such as an antistatic agent and wax are added to a synthetic resin as necessary is prepared. Examples of the method include coating and drying on a release layer already formed on a sheet using a known means such as gravure coating, gravure reverse coating, and roll coating. The thickness of the protective transfer layer to be formed is about 0.5 to 5 μm, preferably about 1 to 2 μm.

[Release layer]
The peelable protective transfer layer according to the present invention is preferably provided on the base sheet via a non-transferable release layer.

  The non-transfer mold release layer always makes the adhesive force between the base sheet and the non-transfer mold release layer sufficiently higher than the adhesive force between the non-transfer mold release layer and the protective transfer layer, For the purpose of increasing the adhesive force between the non-transferring release layer before applying heat and the protective transfer layer relative to that after applying heat, (1) together with the resin binder, the average particle diameter Contains 30 to 80% by mass of inorganic fine particles of 40 nm or less, or (2) contains an alkyl vinyl ether / maleic anhydride copolymer, a derivative thereof, or a mixture thereof in a ratio of 20% by mass or more in total. Or (3) It is preferable that the ionomer is contained in a proportion of 20% by mass or more. The non-transferable release layer may contain other additives as necessary.

  Examples of the inorganic fine particles include silica fine particles such as anhydrous silica and colloidal silica, and metal oxides such as tin oxide, zinc oxide, and zinc antimonate. The particle diameter of the inorganic fine particles is preferably 40 nm or less. If it exceeds 40 nm, the unevenness on the surface of the protective transfer layer is increased due to the unevenness on the surface of the release layer, and as a result, the transparency of the protective transfer layer is lowered, which is not preferable.

  The resin binder to be mixed with the inorganic fine particles is not particularly limited, and any resin that can be mixed can be used. For example, polyvinyl alcohol resins (PVA) of various saponification degrees; polyvinyl acetal resins; polyvinyl butyral resins; acrylic resins; polyamide resins; cellulose resins such as cellulose acetate, alkyl cellulose, carboxymethyl cellulose, hydroxyalkyl cellulose; Examples thereof include resins.

  The blending ratio (inorganic particulate / other blending components) of the inorganic particulates and other blending components mainly composed of a resin binder is preferably in the range of 30/70 or more and 80/20 or less in terms of mass ratio. When the blending ratio is less than 30/70, the effect of the inorganic fine particles becomes insufficient. On the other hand, when the blending ratio exceeds 80/20, the release layer does not become a complete film, and the base sheet and the protective transfer layer are in direct contact with each other. End up.

  Examples of the alkyl vinyl ether / maleic anhydride copolymer or derivatives thereof include those in which the alkyl group of the alkyl vinyl ether portion is a methyl group or an ethyl group, and the maleic anhydride portion is partially or completely alcohol (for example, methanol, ethanol, etc.). , Propanol, isopropanol, butanol, isobutanol and the like) can be used.

  The release layer may be formed only with an alkyl vinyl ether / maleic anhydride copolymer, a derivative thereof, or a mixture thereof. For the purpose of adjusting the peeling force between the release layer and the protective transfer layer, other layers may be used. These resins or fine particles may be further added. In that case, the release layer preferably contains 20% by mass or more of an alkyl vinyl ether / maleic anhydride copolymer, a derivative thereof, or a mixture thereof. When the content is less than 20% by mass, the effect of the alkyl vinyl ether / maleic anhydride copolymer or its derivative cannot be sufficiently obtained.

  The resin or fine particles blended in the alkyl vinyl ether / maleic anhydride copolymer or its derivative is not particularly limited as long as it can be mixed and can provide high film transparency at the time of film formation, and any material can be used. I can do it. For example, the above-mentioned inorganic fine particles and resin binders that can be mixed with the inorganic fine particles are preferably used.

  As the ionomer, for example, Surlyn A (manufactured by DuPont), Chemipearl S series (manufactured by Mitsui Petrochemical Co., Ltd.) or the like can be used. Further, for example, the above-mentioned inorganic fine particles, a resin binder that can be mixed with the inorganic fine particles, or other resins and fine particles can be further added to the ionomer.

  In order to form a non-transferable release layer, a coating solution containing any of the above components (1) to (3) in a predetermined blending ratio is prepared, and the coating solution is subjected to a gravure coating method or gravure reverse. It apply | coats on a base material sheet | seat by well-known techniques like a coating method, and dries an application layer. The thickness of the non-transferable release layer is usually about 0.1 to 2 μm after drying.

  The protective transfer layer laminated on the base sheet with or without the non-transfer release layer may have a multilayer structure or a single layer structure. In the case of a multi-layer structure, in addition to the main protective transfer layer as a main component for imparting various durability to the image, a protective transfer layer is used to increase the adhesion between the protective transfer layer and the image receiving surface of the printed material. May be provided with an adhesive layer disposed on the outermost surface, an auxiliary protective transfer layer, or a layer for adding a function other than the original function of the protective transfer layer (for example, an anti-counterfeit layer, a hologram layer). . The order of the main protective transfer layer and the other layers is arbitrary, but in general, other layers are provided between the adhesive layer and the main protective transfer layer so that the main protective transfer layer becomes the outermost surface of the image receiving surface after transfer. Place.

[Adhesive layer]
An adhesive layer is preferably formed on the outermost surface of the protective transfer layer. The adhesive layer should be formed of a resin having good adhesiveness when heated, such as acrylic resin, vinyl chloride resin, vinyl acetate resin, vinyl chloride / vinyl acetate copolymer resin, polyester resin, polyamide resin. Can do. In addition to the above resin, the above-mentioned ionizing radiation curable resin, ultraviolet blocking resin and the like may be mixed as necessary. The thickness of the adhesive layer is usually 0.1 to 5 μm.

  In order to form a protective transfer layer on a non-transferable release layer or on a substrate sheet, for example, a protective transfer layer coating solution containing a protective transfer layer forming resin, or an adhesive layer containing a thermal adhesive resin A coating solution for forming a coating solution and other layers to be added according to need is prepared in advance, and these are applied in a predetermined order on a non-transferable release layer or a substrate sheet and dried. Each coating solution may be applied by a conventionally known method. Moreover, you may provide an appropriate primer layer between each layer.

[Others]
<UV absorber>
It is preferable that at least one layer of the protective transfer layer unit (peeling layer, protective transfer layer and adhesive layer) contains an ultraviolet absorber, but when it is contained in the transparent resin layer, after the transfer of the protective transfer layer Since the transparent resin layer is present on the outermost surface of the printed material, the effect is reduced over time due to the influence of the environment over a long period of time. Therefore, the transparent resin layer is particularly preferably contained in the heat-sensitive adhesive layer.

  Examples of the ultraviolet absorber include salicylic acid-based, benzophenone-based, benzotriazole-based, and cyanoacrylate-based ultraviolet absorbers. Specifically, for example, Tinuvin P, Tinuvin 234, Tinuvin 320, Tinuvin 326, Tinuvin 327, Tinuvin 328 , Tinuvin 312, Tinuvin 315 (above, manufactured by Ciba Geigy), Sumisorb-110, Sumisorb-130, Sumisorb-140, Sumisorb-200, Sumisorb-250, Sumisorb-300, Sumisorb-320, Sumisorb-340, 350 Sumisorb-400 (above, manufactured by Sumitomo Chemical Co., Ltd.), Mark LA-32, Mar LA-36, Mark 1413 (or more, Adeka Argus Chemical Co., Ltd.) can be obtained from the market under the trade name, etc., both can be used in the present invention.

  Further, a random copolymer having a Tg of 60 ° C. or higher, preferably 80 ° C. or higher, in which a reactive ultraviolet absorber and an acrylic monomer are randomly copolymerized may be used.

  The above-mentioned reactive ultraviolet absorbers are conventionally known salicylates, benzophenones, benzotriazoles, substituted acrylonitriles, nickel chelates, hindered amines and other non-reactive ultraviolet absorbers such as vinyl groups and acryloyl groups, Addition-polymerizable double bonds such as methacryloyl groups, or those having introduced an alcoholic hydroxyl group, amino group, carboxyl group, epoxy group, isocyanate group or the like can be used. Specifically, UVA635L, UVA633L (above, manufactured by BASF Japan Ltd.), PUVA-30M (manufactured by Otsuka Chemical Co., Ltd.) and the like can be obtained from the market, and any of them can be used in the present invention. .

  The amount of the reactive ultraviolet absorbent in the random copolymer of the reactive ultraviolet absorbent and the acrylic monomer as described above is in the range of 10 to 90 mass%, preferably 30 to 70 mass%. Moreover, the molecular weight of such a random copolymer can be about 5000-250,000, Preferably it can be about 9000-30000. The above-mentioned ultraviolet absorber and the random copolymer of the reactive ultraviolet absorber and the acrylic monomer may be contained alone or in combination. The addition amount of the random copolymer of the reactive ultraviolet absorber and the acrylic monomer is preferably 5 to 50% by mass with respect to the layer to be contained.

<Light resistance>
Of course, other light-proofing agents may be included in addition to the ultraviolet absorber. Here, the light-proofing agent is an agent that prevents or alters the degradation or decomposition of the dye by absorbing or blocking the action of degrading or decomposing the dye, such as light energy, thermal energy, and oxidizing action. Besides antioxidants, antioxidants and light stabilizers conventionally known as additives for synthetic resins and the like can be mentioned. In this case, it may be contained in at least one of the protective transfer layers, that is, at least one of the release layer, the transparent resin layer, and the heat-sensitive adhesive layer, but is particularly preferably contained in the heat-sensitive adhesive layer.

<Antioxidant>
Examples of the antioxidant include primary antioxidants such as phenols, monophenols, bisphenols, and amines, and secondary antioxidants such as sulfur and phosphorus. Examples of the light stabilizer include hindered amines.

  Although the usage-amount of the light-proofing agent containing said ultraviolet absorber is not specifically limited, Preferably it is 0.05-10 mass parts per 100 mass parts of resin which forms the layer to contain, Preferably it is a ratio of 3-10 mass parts Used in. If the amount used is too small, it is difficult to obtain an effect as a light-proofing agent.

  In addition to the above light-proofing agent, for example, various additives such as a fluorescent brightening agent and a filler can be simultaneously added to the adhesive layer in an appropriate amount.

  The transparent resin layer of the protective transfer layer transfer sheet may be provided alone on the base sheet, or may be provided in the surface order with the ink layer of the thermal transfer sheet.

[Heat resistant slipping layer]
In the thermal transfer sheet according to the present invention, it is preferable to provide a heat-resistant slipping layer on the surface opposite to the dye layer with the base sheet interposed therebetween.

  The heat resistant slipping layer is provided for the purpose of preventing thermal fusion between a heating device such as a thermal head and a base sheet, smooth running, and removing deposits on the thermal head.

  Examples of the resin used for the heat resistant slipping layer include cellulose resins such as ethyl cellulose, hydroxy cellulose, hydroxypropyl cellulose, methyl cellulose, cellulose acetate, cellulose acetate butyrate, and nitrocellulose, polyvinyl alcohol, polyvinyl acetate, polyvinyl butyral, and polyvinyl. Vinyl resins such as acetal and polyvinyl pyrrolidone, acrylic resins such as polymethyl methacrylate, polyethyl acrylate, polyacrylamide, and acrylonitrile-styrene copolymers, polyimide resins, polyamide resins, polyamideimide resins, polyvinyltoluene resins, polymers A single or mixture of natural or synthetic resins such as malon indene resin, polyester resin, polyurethane resin, silicone-modified or fluorine-modified urethane is used. It is. In order to further improve the heat resistance of the heat resistant slipping layer, among the above resins, a resin having a hydroxyl group-based reactive group is used, and a polyisocyanate or the like is used in combination as a crosslinking agent. It is preferable to do.

  Further, in order to impart slidability with the thermal head, a solid or liquid release agent or lubricant may be added to the heat-resistant slip layer to give heat-resistant slip. Examples of release agents or lubricants include various waxes such as polyethylene wax and paraffin wax, higher aliphatic alcohols, organopolysiloxanes, anionic surfactants, cationic surfactants, amphoteric surfactants, nonionic surfactants. Activators, fluorine surfactants, metal soaps, organic carboxylic acids and derivatives thereof, fluorine resins, silicone resins, fine particles of inorganic compounds such as talc, silica, and the like can be used. The amount of the lubricant contained in the heat resistant slipping layer is 5 to 50% by mass, preferably about 10 to 30% by mass. The thickness of such a heat-resistant slipping layer can be about 0.1 to 10 μm, preferably about 0.3 to 5 μm.

  When the protective transfer layer unit is a laminate of a protective transfer layer and an adhesive layer, the adhesive layer serves to facilitate the transfer of the protective transfer layer to the transfer target. As an adhesive for forming this adhesive layer, it is possible to use a hot-melt adhesive such as acrylic, styrene acrylic, vinyl chloride, styrene-vinyl chloride-vinyl acetate copolymer, vinyl chloride-vinyl acetate copolymer. it can. The adhesive layer can be formed by known means such as gravure coating, gravure reverse coating, roll coating, etc., and the thickness of the adhesive layer is preferably about 0.1 to 5 μm.

(Image forming method)
As the thermal transfer recording apparatus used in the image forming method of the present invention, for example, a thermal transfer recording apparatus as shown in FIG. 4 can be used. In FIG. 4, 21 is a thermal transfer sheet supply roll, 11 is a thermal transfer sheet, 22 is a take-up roll for winding up the used thermal transfer sheet 11, 23 is a thermal head, 24 is a platen roller, 1 is a thermal head 23 and a platen roller. 24 is a thermal transfer image receiving sheet inserted in between.

  A process for forming an image using the thermal transfer recording apparatus shown in FIG. 4 and using, for example, the thermal transfer sheet shown in FIG. 3 will be described. First, the dye layer 13Y containing the yellow dye in FIG. 3 of the thermal transfer sheet and the image receiving layer of the thermal transfer image receiving sheet are overlapped, and the yellow dye in the dye layer 13Y is transferred to the image receiving sheet according to the image data by applying heat from the thermal head 23. A yellow image is then formed, and then the magenta dye is transferred imagewise in the same manner from the dye layer 13M containing the magenta dye on the yellow image, and then the cyan dye is contained on the transferred image. In the same manner, the cyan dye is transferred in an image-like manner from the dye layer 13C to be transferred, and finally, the protective transfer layer unit 14 including the transferable protective transfer layer is thermally transferred from the thermal transfer sheet to the entire surface of the image to complete the image formation. To do.

  In the thermal transfer recording apparatus used in the present invention, it is preferable that gloss and matte controls can be selected in the same apparatus because a printed product with a desired surface property can be obtained with one model. The selection method is not particularly limited. For example, control data corresponding to the glossy tone and matte tone of the present invention is held in the thermal transfer recording apparatus, the control data selected by a simple operation of the operator is read, and the control unit is controlled according to the data. Alternatively, when a personal computer is connected to the recording apparatus, the control data may be held on the personal computer side, and the selected control data may be sent to the recording apparatus by a simple operation by the operator. In addition, when heating with a heat roller, a material that alters the surface, for example, a release sheet that gives gloss, a sheet with unevenness for matting is applied to the surface of the image receiving layer after image recording. By heating with a heat roller from the back side of the sheet, recording bodies having different surfaces can be obtained.

  EXAMPLES Hereinafter, the present invention will be specifically described with reference to examples, but the present invention is not limited thereto.

Example 1
<< Preparation of thermal transfer image-receiving sheet >>
[Preparation of thermal transfer image-receiving sheet 1]
Using coated paper (US basis weight 157 g / m ² OK top coat S, manufactured by Oji Paper Co., Ltd.), one side of the paper is subjected to corona discharge treatment, and then the back side resin layer is formed on the surface as an ethylene-α-olefin copolymer. High-density polyethylene (hereinafter abbreviated as HDPE) blended with 15% by mass of [Toughmer A-4085, Mitsui Petrochemical Co., Ltd.] (J-Rex LZ0139-2 density 0.952, manufactured by Nippon Polyolefin Co., Ltd.) and polypropylene (hereinafter PP) (Jallomer LR711-5 Density 0.905 manufactured by Nippon Polyolefin Co., Ltd.) was co-extruded with a conventionally known multilayer T-die to extrude and laminate two layers so that the HDPE layer side was in contact with the coated paper. In addition, as for the thickness of the back surface resin layer, the extrusion amount was adjusted so that the HDPE layer of the ethylene-α-olefin copolymer blend was 14 μm and the PP layer was 19 μm.

Next, after the corona discharge treatment was applied to the PP layer surface that was on the outside, the back layer coating solution 1 having the following composition was applied under the condition that the dry solid content was 1.5 g / m ² , A support was prepared.

<Backside layer coating solution 1>
Acrylic resin (BR-85 manufactured by Mitsubishi Rayon Co., Ltd.) 19.8 parts by mass Nylon filler (MW-330 manufactured by Shinto Paint Co., Ltd.) 0.6 parts by mass Methyl ethyl ketone 39.8 parts by mass Toluene 39.8 parts by mass 35 μm thick foamed polypropylene sheet (35MW846 Mobile Plastics Europe) having an intermediate layer coating solution 1 having the structure described in Table 1 on one side and an image receiving layer coating solution described below 1 is coated and dried sequentially by gravure reverse coating so that the film thickness after drying becomes 1.0 μm (intermediate layer) and 3.0 μm (image receiving layer), respectively. A foamed polypropylene sheet in which layers were laminated was produced.

Next, the surface of the foamed polypropylene sheet opposite to the surface having the intermediate layer and the receiving layer and the surface opposite to the surface having the back surface layer of the prepared coated paper support 1 are composed of the following composition: The thermal transfer image receiving sheet 1 was produced by pasting together by using a dry laminating method. In addition, when the specific gravity of urethane resin (Nipporan 5199, manufactured by Nippon Polyurethane Co., Ltd.), antistatic agent SN-100P (produced by Ishihara Techno Co., Ltd.), polyester resin (Byron 245, manufactured by Toyobo Co., Ltd.) was separately measured, 6.6 and 1.4 g / cm ³ .

(Image-receiving layer coating solution 1)
Vinyl chloride-vinyl acetate copolymer (Denka vinyl # 1000A, manufactured by Denki Kagaku Kogyo Co., Ltd.)
7.2 parts by mass Vinyl chloride-styrene-acrylic copolymer (Denkarac # 400, manufactured by Denki Kagaku Kogyo Co., Ltd.) 1.6 parts by mass Polyester (Byron 600, manufactured by Toyobo Co., Ltd.) 11.2 parts by mass Metal ion-containing compound: MS -1 (* 1) 3 parts by mass Vinyl-modified silicone (X-62-1212 manufactured by Shin-Etsu Chemical Co., Ltd.) 2.0 parts by mass Catalyst: CAT PLR-5 (manufactured by Shin-Etsu Chemical Co., Ltd.) 1.0 part by mass Catalyst: CAT PL-50T (manufactured by Shin-Etsu Chemical Co., Ltd.) 1.2 parts by mass Solvent: methyl ethyl ketone 39.0 parts by mass Solvent: toluene 39.0 parts by mass (* 1) MS-1: Ni ²⁺ [C ₇ H ₁₅ COC (COOCH ₃ ) = C (CH ₃ ) O ⁻ ] ₂
(adhesive)
Polyfunctional polyol (Takelac A-969V, Takeda Pharmaceutical Company Limited) 30.0 parts by mass Isocyanate (Takenate A-5, Takeda Pharmaceutical Company Limited) 10.0 parts by mass Solvent: Ethyl acetate 60.0 parts by mass [Thermal transfer image-receiving sheet 2 Production of ~ 18]
In the production of the thermal transfer image receiving sheet 1, thermal transfer image receiving sheets 2 to 18 were produced in the same manner except that the intermediate layer coating solution 1 was changed to the intermediate layer coating solutions 2 to 18, respectively.

  Table 1 shows the composition of each intermediate layer coating solution used in the thermal transfer image-receiving sheets 1 to 18 produced as described above, and the volume ratio of the antistatic agent to the total solid volume of the intermediate layer.

  The details of each additive listed in Table 1 are as follows.

Urethane resin: NIPPOLAN 5199 Made by Nippon Polyurethane Co., Ltd. Solid content 30% by mass
Polyester resin: Byron 245 manufactured by Toyobo Co., Ltd. Antistatic agent: SN-100P manufactured by Ishihara Techno Co., Ltd. Titanium oxide: TCA888TC manufactured by Tochem Products Co., Ltd. Manufacture Solvent 1: Methyl ethyl ketone Solvent 2: Acetone Solvent 3: Isopropyl alcohol

[Preparation of Thermal Transfer Image Receiving Sheets 19-21]
In the production of the thermal transfer image-receiving sheet 4, instead of the back layer coating solution 1 used in the support 1, the following back layer coating solutions 2, 3, and 4 have a solid content of 1.5 g / m ² after drying. Thus, thermal transfer image-receiving sheets 19 to 21 were produced in the same manner except that the support bodies 2, 3, and 4 on which a cellulose-based back layer was formed were applied and dried.

(Back layer coating solution 2: for thermal transfer image receiving sheet 19)
Cellulose acetate (CA398-10 manufactured by Eastman Chemical Co.) 10 parts by weight Nylon filler (MW-330 manufactured by Shinto Paint Co., Ltd.) 0.5 parts by weight Acetone 200 parts by weight Cyclohexanone 20 parts by weight (Back layer coating solution 3: thermal transfer image-receiving sheet 20)
Cellulose acetate butyrate (CAB381-20 manufactured by Eastman Chemical Co.)
10 parts by mass Nylon filler (MW-330, manufactured by Shinto Paint Co., Ltd.) 0.5 parts by mass Acetone 200 parts by mass Cyclohexanone 20 parts by mass (Back layer coating solution 4: for thermal transfer image-receiving sheet 21)
Cellulose acetate propionate (CAP482-20 manufactured by Eastman Chemical Co., Ltd.) 10 parts by mass Nylon filler (MW-330, manufactured by Shinto Paint Co., Ltd.) 0.5 parts by mass Acetone 200 parts by mass Cyclohexanone 20 parts by mass [Preparation of Thermal Transfer Image Receiving Sheet 22 ]
In the production of the thermal transfer image receiving sheet 19, the intermediate layer coating solution 4 is changed to the intermediate layer coating solution 19 having the following composition, and the image receiving layer coating solution 2 having the following composition is used instead of the image receiving layer coating solution 1. A thermal transfer image-receiving sheet 22 was produced in the same manner except that. In addition, Denka vinyl # 1000A (manufactured by Denki Kagaku Kogyo Co., Ltd.) / Denka rack # 400 (manufactured by Denki Kagaku Kogyo Co., Ltd.) / Byron 600 (manufactured by Toyobo Co., Ltd.) = 7.2 parts by mass / 1.6 masses used in the image receiving layer 2 The specific gravity of the mixture / part by weight of 11.2 parts by mass was separately measured and found to be 1.3 g / cm ³ .

(Intermediate layer coating solution 19)
Urethane resin (Nipporan 5199, manufactured by Nippon Polyurethane Co., Ltd.) 5.7 parts by mass Titanium oxide (TCA888, manufactured by Tochem Products) 11.4 parts by mass Fluorescent whitening agent (Ubitex OB, manufactured by Ciba Geigy Japan) 0.2 Isocyanate (Takenate A-14, Takeda Pharmaceutical Company Limited) 2.0 parts by weight Methyl ethyl ketone 15.5 parts by weight Toluene 15.5 parts by weight Isopropyl alcohol 7.7 parts by weight (Image-receiving layer coating solution 2)
Vinyl chloride-vinyl acetate copolymer (Denka vinyl # 1000A, manufactured by Denki Kagaku Kogyo Co., Ltd.)
7.2 parts by mass Vinyl chloride-styrene-acrylic copolymer (Denkarac # 400, manufactured by Denki Kagaku Kogyo) 1.6 parts by mass Polyester (Byron 600, manufactured by Toyobo Co., Ltd.) 11.2 parts by mass MS-1 ( 3) parts by weight Antistatic agent (SN-100P, manufactured by Ishihara Techno) 54.7 parts by weight Vinyl-modified silicone (X-62-1212, manufactured by Shin-Etsu Chemical Co., Ltd.) 2.0 parts by weight Catalyst (CAT PLR- 5 manufactured by Shin-Etsu Chemical Co., Ltd.) 1.0 part by mass Catalyst (CAT PL-50T manufactured by Shin-Etsu Chemical Co., Ltd.) 1.2 parts by mass Methyl ethyl ketone 39.0 parts by mass Toluene 39.0 parts by mass [Preparation of thermal transfer image-receiving sheet 23]
In the production of the thermal transfer image-receiving sheet 19, the intermediate layer coating solution 4 is applied onto the foamed polypropylene sheet, and then the second intermediate layer having the following composition is applied thereon so that the dry film thickness is 0.5 μm. Then, a thermal transfer image receiving sheet 23 was produced in the same manner except that the image receiving layer coating solution 2 was laminated.

(Second intermediate layer coating solution)
Urethane resin (Nipporan 5199, manufactured by Nippon Polyurethane) 10 parts by weight Antistatic agent (SN-100P, manufactured by Ishihara Techno) 16.5 parts by weight Methyl ethyl ketone 10 parts by weight Toluene 10 parts by weight Isopropyl alcohol 5 parts by weight [Thermal transfer image receiving sheet Production of 24 and 25]
In the production of the thermal transfer image-receiving sheets 3 and 4, the same amount of the antistatic agent (SN-100P, manufactured by Ishihara Techno) used in the intermediate layer coating solution was used (FS-10P, manufactured by Ishihara Techno). Thermal transfer image receiving sheets 24 and 25 were produced in the same manner except that the following intermediate layer coating solutions 20 and 21 were used.

(Intermediate layer coating solution 20)
Urethane resin (Nipporan 5199, manufactured by Nippon Polyurethane Co., Ltd.) 5.7 parts by mass Antistatic agent (FS-10P, manufactured by Ishihara Techno Co., Ltd.) 5.1 parts by mass Titanium oxide (TCA888, manufactured by Tochem Products) 11.4 parts by mass Parts fluorescent whitening agent (Ubitex OB, manufactured by Ciba Geigy Japan) 0.2 parts by mass Isocyanate (Takenate A-14, manufactured by Takeda Pharmaceutical Co., Ltd.) 2.0 parts by weight Methyl ethyl ketone 15.5 parts by weight Toluene 15.5 parts by weight 7.7 parts by mass of isopropyl alcohol (intermediate layer coating solution 21)
Urethane resin (Nipporan 5199, manufactured by Nippon Polyurethane Co., Ltd.) 5.7 parts by mass Antistatic agent (FS-10P, manufactured by Ishihara Techno) 9.4 parts by mass Titanium oxide (TCA888, manufactured by Tochem Products) 11.4 parts by mass Parts fluorescent whitening agent (Ubitex OB, manufactured by Ciba Geigy Japan) 0.2 parts by mass Isocyanate (Takenate A-14, manufactured by Takeda Pharmaceutical Co., Ltd.) 2.0 parts by weight Methyl ethyl ketone 15.5 parts by weight Toluene 15.5 parts by weight 7.7 parts by mass of isopropyl alcohol [Preparation of thermal transfer image-receiving sheet 26]
A thermal transfer image receiving sheet 26 was prepared in the same manner as in the production of the thermal transfer image receiving sheet 19 except that the intermediate layer coating solution 4 was changed to the prepared intermediate layer coating solution 21.

[Preparation of thermal transfer image receiving sheet 27]
A thermal transfer image receiving sheet 27 was prepared in the same manner as in the production of the thermal transfer image receiving sheet 26 except that the intermediate layer coating liquid 21 was changed to the intermediate layer coating liquid 22 instead of the intermediate layer coating liquid 21. In addition, it was 4.5 g / cm < ³ > when the specific gravity of antistatic agent ET-600W (made by Ishihara Techno Co.) was measured separately.

(Intermediate layer coating solution 22)
Urethane resin (Nipporan 5199, 30% solid content by Nippon Polyurethane)
5.7 parts by weight Antistatic agent (ET-600W, manufactured by Ishihara Techno) 5.25 parts by weight Titanium oxide (TCA888, manufactured by Tochem Products) 11.4 parts by weight Fluorescent whitening agent (Ubitex OB, Nippon Ciba Geigy) 0.2 mass parts Isocyanate (Takenate A-14, Takeda Pharmaceutical Company Limited) 2.0 mass parts Methyl ethyl ketone 15.5 mass parts Toluene 15.5 mass parts Isopropyl alcohol 7.7 mass parts [Thermal transfer image receiving sheet 28 Production)
In the production of the thermal transfer image-receiving sheet 27, the support 2 was changed to the support 4, and the intermediate layer coating solution 22 was replaced with an intermediate layer coating solution 23 having the following composition. A thermal transfer image receiving sheet 28 was produced.

(Intermediate layer coating solution 23)
Urethane resin (Nipporan 5199, 30% solid content by Nippon Polyurethane)
5.7 parts by mass Antistatic agent (FT-3000, manufactured by Ishihara Techno) 5.13 parts by mass Titanium oxide (TCA888, manufactured by Tochem Products) 11.4 parts by mass Fluorescent whitening agent (Ubitex OB, Nippon Ciba Geigy) 0.2 mass parts Isocyanate (Takenate A-14, Takeda Pharmaceutical Company Limited) 2.0 mass parts Methyl ethyl ketone 15.5 mass parts Toluene 15.5 mass parts Isopropyl alcohol 7.7 mass parts [Thermal transfer image receiving sheet 29 Production)
A thermal transfer image receiving sheet 29 was prepared in the same manner as in the production of the thermal transfer image receiving sheet 26 except that the intermediate layer coating solution 24 was changed to the intermediate layer coating solution 24 having the following composition instead of the intermediate layer coating solution 21. The specific gravity of the antistatic agent Laponite JS (made by Nippon Silica Kogyo Co., Ltd.) was measured separately and found to be 0.91 g / cm ³ .

(Intermediate layer coating solution 24)
Urethane resin (Nipporan 5199, manufactured by Nippon Polyurethane Co., Ltd.) 5.7 parts by mass Antistatic agent (Laponite JS, manufactured by Nippon Silica Industry Co., Ltd.) 1.07 parts by mass Titanium oxide (TCA888, manufactured by Tochem Products) 11.4 parts by mass Parts fluorescent whitening agent (Ubitex OB, manufactured by Ciba Geigy Japan) 0.2 parts by mass Isocyanate (Takenate A-14, manufactured by Takeda Pharmaceutical Co., Ltd.) 2.0 parts by weight Methyl ethyl ketone 15.5 parts by weight Toluene 15.5 parts by weight 7.7 parts by mass of isopropyl alcohol [Preparation of thermal transfer image receiving sheet 30]
In the production of the thermal transfer image-receiving sheet 22, the thermal transfer image-receiving sheet 30 was prepared in the same manner except that the support 2 was changed to the support 1 and the image-receiving layer coating solution 2 was changed to the image-receiving layer coating solution 3 having the following composition. Produced.

(Image-receiving layer coating solution 3)
Vinyl chloride-vinyl acetate copolymer (Denka vinyl # 1000A, manufactured by Denki Kagaku Kogyo Co., Ltd.)
7.2 parts by mass Vinyl chloride-styrene-acrylic copolymer (Denkarac # 400, manufactured by Denki Kagaku Kogyo) 1.6 parts by mass Polyester (Byron 600, manufactured by Toyobo Co., Ltd.) 11.2 parts by mass MS-1 ( 3) parts by weight Antistatic agent (Laponite JS, manufactured by Nippon Silica Kogyo Co., Ltd.) 14 parts by weight Vinyl-modified silicone (X-62-1212, manufactured by Shin-Etsu Chemical Co., Ltd.) 2.0 parts by weight Catalyst (CAT PLR-5 Shin-Etsu) 1.0 mass parts Catalyst (CAT PL-50T, Shin-Etsu Chemical Co., Ltd.) 1.2 mass parts Methyl ethyl ketone 39.0 mass parts Toluene 39.0 mass parts [Preparation of thermal transfer image-receiving sheet 31]
A thermal transfer image receiving sheet 31 was prepared in the same manner as the thermal transfer image receiving sheet 1 except that the intermediate layer coating solution 1 was changed to an intermediate layer coating solution 25 having the following composition.

(Intermediate layer coating solution 25)
Urethane resin (Nipporan 5199, manufactured by Nippon Polyurethane Co., Ltd.) 5.7 parts by mass Antistatic agent (cross-linking cation: copoly [N-vinylbenzyl-N, N, N-trimethylammonium chloride-co-ethylene glycol diacrylate] 93: 7) 1.85 parts by mass Titanium oxide (TCA888, manufactured by Tochem Products) 11.4 parts by mass Fluorescent whitening agent (Ubitex OB, manufactured by Ciba Geigy Japan) 0.2 parts by mass Isocyanate (Takenate A-14, Takeda) 2.0 parts by mass Methyl ethyl ketone 15.5 parts by mass Toluene 15.5 parts by mass Isopropyl alcohol 7.7 parts by mass [Preparation of thermal transfer image-receiving sheet 32]
In the production of the thermal transfer image receiving sheet 31, the thermal transfer image receiving sheet was similarly obtained except that the support 1 was changed to the support 2 and the intermediate layer coating solution 25 was changed to the intermediate layer coating solution 26 having the following composition. 32 was produced.

(Intermediate layer coating solution 26)
Urethane resin (Nipporan 5199, manufactured by Nippon Polyurethane Co., Ltd.) 5.7 parts by mass Antistatic agent (cross-linking cation: copoly [N-vinylbenzyl-N, N, N-trimethylammonium chloride-co-ethylene glycol diacrylate] 93: 7) 4.32 parts by mass Titanium oxide (TCA888, manufactured by Tochem Products) 11.4 parts by mass Optical brightener (Ubitex OB, manufactured by Ciba Geigy Japan) 0.2 parts by mass Isocyanate (Takenate A-14, Takeda) 2.0 parts by mass Methyl ethyl ketone 15.5 parts by mass Toluene 15.5 parts by mass Isopropyl alcohol 7.7 parts by mass [Preparation of thermal transfer image-receiving sheet 33]
A thermal transfer image receiving sheet 33 was prepared in the same manner as in the production of the thermal transfer image receiving sheet 4 except that the image receiving layer coating liquid 1 was changed to the image receiving layer coating liquid 4 having the following composition.

(Image-receiving layer coating solution 4)
Vinyl chloride-vinyl acetate copolymer [Denka Vinyl # 1000A, manufactured by Denki Kagaku Kogyo Co., Ltd.]
7.2 parts by mass Vinyl chloride-styrene-acrylic copolymer [Denkarak # 400, manufactured by Denki Kagaku Kogyo Co., Ltd.] 1.6 parts by mass Polyester [Byron 600, manufactured by Toyobo Co., Ltd.] 11.2 parts by mass Vinyl-modified silicone [X- 62-1212 manufactured by Shin-Etsu Chemical Co., Ltd.] 2.0 parts by mass Catalyst [CAT PLR-5 manufactured by Shin-Etsu Chemical Co., Ltd.] 1.0 part by mass Catalyst [CAT PL-50T manufactured by Shin-Etsu Chemical Co., Ltd.] 1.2 parts by mass Solvent: Methyl ethyl ketone 39.0 parts by mass Solvent: Toluene 39.0 parts by mass [Production of thermal transfer image-receiving sheet 34: Comparative example]
A thermal transfer image receiving sheet 34 was prepared in the same manner as in the production of the thermal transfer image receiving sheet 30 except that the image receiving layer coating solution 3 was changed to the image receiving layer coating solution 5 having the following composition.

(Image-receiving layer coating solution 5)
Vinyl chloride-vinyl acetate copolymer (Denka vinyl # 1000A, manufactured by Denki Kagaku Kogyo Co., Ltd.)
7.2 parts by mass Vinyl chloride-styrene-acrylic copolymer (Denkarac # 400, manufactured by Denki Kagaku Kogyo) 1.6 parts by mass Polyester (Byron 600, manufactured by Toyobo Co., Ltd.) 11.2 parts by mass Antistatic agent ( Surfactant, quaternary ammonium salt, KS-555 manufactured by Kao Corporation
20 parts by mass Vinyl-modified silicone (X-62-1212, manufactured by Shin-Etsu Chemical Co., Ltd.) 2.0 parts by mass Catalyst (CAT PLR-5, manufactured by Shin-Etsu Chemical Co., Ltd.) 1.0 part by mass Catalyst (CAT PL-50T Shin-Etsu Chemical Co., Ltd.) 1.2 parts by mass Methyl ethyl ketone 39.0 parts by mass Toluene 39.0 parts by mass [Production of thermal transfer image-receiving sheet 35: comparative example]
A thermal transfer image receiving sheet 35 was prepared in the same manner as the thermal transfer image receiving sheet 30 except that the image receiving layer coating solution 3 was changed to the image receiving layer coating solution 1.

  Table 2 shows main components of the thermal transfer image-receiving sheets 1 to 35 produced as described above.

<Production of thermal transfer sheet>
[Preparation of thermal transfer sheet 1]
A cyan dye coating solution 1 having the following composition on the surface opposite to the surface having a heat-resistant protective layer of a polyethylene terephthalate film (K-203E-6F, manufactured by Diafoil Hoechst) having a heat-resistant protective layer having a thickness of 6 μm, Each dye layer (dry film thickness is 1 μm) formed using the magenta dye coating solution 1 and the yellow dye coating solution 1 and a protective transfer layer unit (non-transferable release layer / protective layer / adhesive layer 3) having a multilayer structure The layer structure) was provided in the surface order as shown in FIG. 3 by the gravure method, and the thermal transfer sheet 1 was produced.

[Each dye layer]
(Cyan dye layer coating solution 1)
Post chelate dye (C-1) 3 parts by mass Polyvinyl butyral (KY-24 manufactured by Denki Kagaku Kogyo Co., Ltd.) 5.5 parts by mass Urethane-modified silicone resin (Diaroma SP-2105 manufactured by Dainichi Seika Co., Ltd.)
1.5 parts by mass Methyl ethyl ketone 80 parts by mass Cyclohexanone 10 parts by mass (Magenta dye layer coating solution 1)
Post chelate dye (M-1) 3 parts by mass Polyvinyl butyral (KY-24, manufactured by Denki Kagaku Kogyo Co., Ltd.) 5.5 parts by mass Urethane-modified silicone resin (Dai-Nisei Chemical Co., Ltd. Dialomer SP-2105)
1.5 parts by mass Methyl ethyl ketone 80 parts by mass Cyclohexanone 10 parts by mass (Yellow dye layer coating solution 1)
Post chelate dye (Y-1) 1 part by weight Polyvinyl butyral (KY-24 manufactured by Denki Kagaku Kogyo Co., Ltd.) 5.5 parts by weight Urethane-modified silicone resin (Daromar SP-2105 manufactured by Dainichi Seika Co., Ltd.)
1.5 parts by mass Methyl ethyl ketone 80 parts by mass Cyclohexanone 10 parts by mass

[Protective transfer layer unit]
(Non-transferable release layer)
A non-transferable release layer coating solution 1 having the following composition was coated by a gravure coating method so that the solid content after drying was 0.5 g / m ² and dried to form a non-transferable release layer. .

<Non-transferable release layer coating solution 1>
Colloidal silica (Snowtex 50 manufactured by Nissan Chemical Co., Ltd.) 1.5 parts by mass Polyvinyl alcohol 4.0 parts by mass Deionized water 3.0 parts by mass Denatured ethanol 10 parts by mass (Protective transfer layer)
On the formed non-transferable release layer, a protective transfer layer coating solution 1 having the following composition was applied and dried by a gravure coating method so that the solid content after drying was 2.0 g / m ² . A protective transfer layer was formed.

<Protective transfer layer coating solution 1>
Acrylic resin 15 parts by weight Vinyl chloride-vinyl acetate copolymer 5 parts by weight Polyethylene wax 0.3 part by weight Polyester resin 0.1 part by weight Methyl ethyl ketone 40 parts by weight Toluene 40 parts by weight (Adhesive layer)
On the protective transfer layer thus formed, the adhesive layer coating solution 1 having the following composition is applied and dried by a gravure coating method so that the solid content after drying is 2.0 g / m ^2. Formed.

<Adhesive layer coating solution 1>
Vinyl chloride-vinyl acetate copolymer 20 parts by mass Methyl ethyl ketone 100 parts by mass Toluene 100 parts by mass By the above, the protective transfer layer, which is a laminate of the protective transfer layer and the adhesive layer, can be peeled off on the non-transferable release layer A provided multi-layer protective transfer layer was prepared.

[Preparation of thermal transfer sheet 2]
In the production of the thermal transfer sheet 1, a thermal transfer sheet 2 was produced in the same manner except that the protective transfer layer coating solution 2 having the following composition was used instead of the protective transfer layer coating solution 1.

<Protective transfer layer coating solution 2>
Acrylic resin 15 parts by weight Vinyl chloride-vinyl acetate copolymer 5 parts by weight Copolymerized resin (UVA-635L manufactured by BASF Japan) with reactive UV absorber 40 parts by weight Polyethylene wax _ 0.3 part by weight Polyester resin 0.1 parts by mass Methyl ethyl ketone 40 parts by mass Toluene 40 parts by mass Zinc antimonate (Sellnax manufactured by Nissan Chemical Co., Ltd.) 20 parts by mass [Preparation of thermal transfer sheet 3]
In the preparation of the thermal transfer sheet 1, instead of the cyan dye layer coating solution 1, the magenta dye layer coating solution 1, and the yellow dye layer coating solution 1, a cyan dye layer coating solution 2 and a magenta dye layer coating solution 2 having the following compositions are used. A thermal transfer sheet 3 was prepared in the same manner except that the yellow dye layer coating solution 2 was used.

(Cyan dye layer coating solution 2)
In the cyan dye layer coating solution 1, a cyan dye layer coating solution 2 was prepared in the same manner except that a cyan disperse dye (CI Solvent Blue 63) was used instead of the post-chelate dye (C-1). .

(Magenta dye layer coating solution 2)
A magenta dye layer coating solution 2 was prepared in the same manner as in the magenta dye layer coating solution 1, except that a magenta disperse dye (CI Disperse Red 60) was used instead of the post-chelate dye (M-1). .

(Yellow dye layer coating solution 2)
In the yellow dye layer coating solution 1, 5.5 parts by mass of yellow disperse dyes shown below and 90 parts by mass of methyl ethyl ketone / toluene (mass ratio 1/1) are used instead of the post-chelate dye (Y-1). A yellow dye layer coating solution 2 was prepared in the same manner except that.

<Image formation>
Using the sublimation thermal transfer printer (CHC-S545, manufactured by Shinko Electric Co., Ltd.) for each thermal transfer image receiving sheet in combination of the produced thermal transfer image receiving sheets 1 to 35 and the thermal transfer sheets 1 to 3 in Table 3, 255 gradation values In addition, Y, M, and C colors were printed at gradation values for every 20 gradations, and then the entire image was post-heated with the same thermal head to produce image formations 1 to 37.

<Evaluation of formed image>
[Measurement of electrical resistance of thermal transfer image-receiving sheet]
In accordance with the method described above, the electrical resistance value of the thermal transfer image-receiving sheet before and after printing was measured by the salt bridge method.

[Evaluation of image preservation]
After each print sample was stored for 3 months in an environment of 60 ° C. and 80% RH, the density residual ratio before and after the storage process of the density 1.0 portion of the magenta image was measured, and the image was evaluated according to the evaluation criteria described below. The storage stability was evaluated. The density of the image was measured using a densitometer X-rite 310 manufactured by X-rite.

A: Magenta density residual ratio is 90% or more. B: Magenta density residual ratio is 70% or more and less than 90%. Δ: Magenta density residual ratio is 50% or more and less than 70%. X: Magenta density residual ratio is 50%. Less than [Evaluation of scratch resistance]
The surface of the portion to which the protective transfer layer was transferred was continuously rubbed with a plastic eraser for 10 seconds, and the residual image density ratio before and after rubbing was measured.

A: Image density remaining rate is 90% or more. O: Image density remaining rate is 70% or more and less than 90%. Δ: Image density remaining rate is 50% or more and less than 70%. X: Image density remaining rate is 50%. Less than [Evaluation of adhesiveness]
After applying the mending tape (manufactured by Sumitomo 3M) to the surface of the protective transfer layer and then removing it ten times in succession, the peeled areas of the protective transfer layer, the image receiving layer, the intermediate layer, etc. Was measured and the adhesion was evaluated according to the following criteria.

◎: No peeling at all ◯: The peeling area is less than 20% of the total area where the tape is applied. Δ: The peeling area is 20% or more and less than 50% of the total area where the tape is applied. 50% or more and less than 100% of the total area where the tape is applied XX: peeling area is 100% or more of the total area where the tape is applied Note that the peeling area is 100% or more and protects more than the area where the tape is applied It means that the transfer layer, the image receiving layer, the intermediate layer and the like have been peeled off.

[Evaluation of judgment]
The thermal transfer image-receiving sheet and the thermal transfer sheet were subjected to continuous solid black printing in an environment of 23 ° C. and 55% RH using a sublimation thermal transfer printer (CHC-S545 manufactured by Shinko Electric Co., Ltd.) in the combinations shown in Table 3. . The work of aligning the 10 image formations obtained was evaluated, and the dispersibility was evaluated according to the following criteria.

◎: Can be aligned without any catches ○: Slightly caught, but can be easily aligned △: Slightly strong catches are recognized, but somehow can be aligned ×: Very strong catch is recognized Table 3 shows the measurement results and evaluation results obtained as described above.

  As is apparent from the results in Table 3, the thermal transfer image-receiving sheet having the configuration defined in the present invention and the image formed product using the thermal transfer sheet have storability and durability of the protective transfer layer (abrasion resistance, adhesiveness). It can be seen that the dispersibility (antistatic property) is improved without deterioration. In particular, it can be seen that an image formed product having a volume content of the conductive agent of 35 to 70% by volume is more preferable because the decrease in conductivity due to transfer of the protective transfer layer is small and the adhesiveness is not decreased. It can also be seen that the image recording material using the cellulose-based resin in the back layer of the thermal transfer image-receiving sheet is further improved in the dispersibility.

It is a schematic diagram which shows an example of the salt bridge method resistance measuring apparatus used for the measurement of the electrical resistance value which concerns on this invention. It is a schematic sectional drawing which shows an example of a structure of the thermal transfer image receiving sheet which concerns on this invention. It is a perspective view which shows an example of the form with which the 1st surface of the thermal transfer sheet which concerns on this invention is supplied sequentially. It is a schematic diagram showing an example of a thermal transfer recording apparatus used in the image forming method of the present invention.

Explanation of symbols

A A recess for holding a buffer solution B Metal electrode C Acrylic plate D Teraohm meter E, 1 Thermal transfer image-receiving sheet 2, 12 Base sheet 3 Dye-receiving layer 4 Back layer 4
DESCRIPTION OF SYMBOLS 5 Conductive layer 11 Thermal transfer sheet 13Y, 13M, 13C Dye layer 14 Protective transfer layer unit 15 Non-transferring peeling layer 16 Protective transfer layer 17 Adhesive layer 21 Heat transfer sheet supply roll 22 Winding roll for winding up the used thermal transfer sheet 23 Thermal head 24 Platen roller

Claims (9)

After forming an image by thermal transfer on a thermal transfer image-receiving sheet having an image-receiving layer on a substrate, protective transfer using a thermal transfer sheet provided with a peelable protective transfer layer on at least a part of one surface of the substrate sheet An image formed by using a thermal transfer system for transferring a layer, wherein the electric resistance measured by the salt bridge method of the thermal transfer image-receiving sheet before the protective transfer layer is transferred is from 1 × 10 ⁸ to 1 × 10 ¹² Ω / □, and having the transferred protective transfer layer, and removing the layer coated on the side opposite to the image forming surface, by the salt bridge method on the image receiving surface side of the image forming surface An image-formed product having a measured electric resistance of 1 × 10 ⁸ to 1 × 10 ¹² Ω / □. The image-formed product according to claim 1, wherein the thermal transfer image-receiving sheet has a conductive layer containing a particulate conductive agent on a surface side on which an image is formed. 2. The image-formed product according to claim 1, wherein the thermal transfer image-receiving sheet has a conductive layer containing a particulate conductive agent between the image-receiving layer and the substrate. 4. The image-formed product according to claim 2, wherein the conductive agent is at least one selected from crystalline metal oxide fine particles, ionic crosslinkable polymer fine particles, and smectite clay mineral fine particles. 5. The image formed product according to claim 2, wherein a volume ratio of the conductive fine particles in the conductive layer is 25 to 80%. 5. The image formed product according to claim 2, wherein a volume ratio of the conductive fine particles in the conductive layer is 35 to 70%. 7. The image-receiving layer of the thermal transfer image-receiving sheet contains a metal ion-containing compound that reacts with a chelatable heat-diffusible dye diffused from a dye layer provided on the thermal transfer sheet. The image-formed product according to any one of the above. The thermal transfer image-receiving sheet has a layer whose outermost surface is mainly composed of a cellulose-based resin on a surface opposite to a surface on which an image is formed with the substrate interposed therebetween. The image-formed product according to any one of the above. An image forming method for producing the image formed product according to claim 1.

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