JP2007136995A - Thermal transfer image accepting sheet - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To solve the problems with a conventional thermal transfer image accepting sheet that nonuniformity is apt to occur in a highlight part of a transfer image and that a bleed-out, a surface stain and a fall in persistence of an effect of giving electroconductivity are apt to take place therein. <P>SOLUTION: In a thermal transfer image accepting sheet which has on one side of a base a dye accepting layer constituted mainly of a binder resin having dyeing properties, the dye accepting layer or at least one other layer provided on one or the other side of the base and containing a resin is made to contain a metallic ion conducting agent prepared by dispersing in a matrix at least one kind of electrolytic metal salt selected from organic or inorganic salts of potassium, barium, sodium and strontium. By this constitution, the occurrence of the nonuniformity in the highlight part of the transfer image can be reduced and the electroconductivity being equal to or more than that of a lithium ion conductive resin can be given thereto. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a thermal transfer image-receiving sheet used for a thermal transfer printer and comprising a support (hereinafter referred to as a base material) and a dye-receiving layer formed on the base material, and particularly has excellent antistatic properties. The present invention relates to a thermal transfer image receiving sheet.

  Conventionally, using a thermal transfer sheet in which a sublimation dye is coated on a substrate made of polyethylene terephthalate (PET) or the like and a thermal head having a heating element that selectively applies a voltage based on a recording signal, A thermal transfer image-receiving sheet provided on a substrate with a dye-receiving layer having the thermal head pressed against the thermal transfer sheet, and applying a voltage to the heating element of the thermal head based on recorded information; A so-called sublimation type thermal recording system is known in which desired recording is performed by transferring the dye to a dye receiving layer of the thermal transfer image receiving sheet.

Conventionally, when an image is formed on a thermal transfer image receiving sheet using such a thermal transfer sheet, the material constituting the thermal transfer image receiving sheet generally has a high surface resistivity of, for example, about 10 ¹⁴ Ω / □. It was easy to be charged with the generation of static electricity due to friction during use. For this reason, dust or the like is likely to adhere to the surface of the thermal transfer image receiving sheet, white spots occur in the transferred image at the adhering dust portion, or wrinkles occur on the thermal transfer sheet in contact with the thermal transfer image receiving sheet, leading to a decrease in resolution. There was a problem such as. In addition, there has been a problem that due to charging, sticking occurs between the thermal transfer image receiving sheet and the thermal transfer sheet, resulting in poor conveyance.

  As means for solving this problem, it has been proposed to form an antistatic layer made of an acrylic resin having a quaternary ammonium base (Patent Document 1). However, when conductivity is to be imparted by a surfactant-based conductivity imparting agent such as a quaternary ammonium salt, the ion conduction requires assistance from moisture in the air, so that conductivity is reduced when humidity is lowered. There was a problem that the remarkably deteriorated.

  Therefore, as a thermal transfer image receiving sheet with little decrease in conductivity even when humidity is lowered, it is a thermal transfer image receiving sheet in which at least a dye receiving layer is provided on at least one surface of a substrate, and a lithium ion conductive resin is at least the outermost surface layer. Or a thermal transfer image-receiving sheet characterized by being contained in a layer under the outermost surface layer (base material side) (Patent Document 2).

Japanese Patent Laid-Open No. 06-55868 JP 2005-96344 A

However, when the dye-receiving layer is formed using the lithium ion conductive resin disclosed in Patent Document 2, for example, there is a problem that variation occurs in conductivity expression for each image receiving sheet. Unevenness is likely to occur in the highlight portion of the transferred image; (2) Bleed-out is likely to occur, and problems such as surface contamination and a decrease in the sustainability of the conductivity imparting problem have also occurred.
As a result of various studies by the present inventors, the problem of (1) is that the lithium ion conductive resin introduced to develop the desired conductivity is uniformly dispersed in the dye dyeing resin of the dye receiving layer. In addition, the problem of the above (2) is caused by the fact that the matrix resin of the lithium ion conductive resin has a hydroxyl group at the terminal, so that bleed-out is likely to occur due to the involvement of temperature and humidity. It became clear.

  The present invention is intended to solve the problems of such a conventional configuration, and no unevenness occurs in the highlight portion of the image, and the conductivity is equal to or higher than that of the lithium ion conductive resin. It is an object of the present invention to provide a thermal transfer image-receiving sheet and a method for producing the same.

  In order to achieve the above object, the present invention is a thermal transfer image-receiving sheet having a dye-receiving layer mainly composed of a binder resin having dye-dyeing property on one surface of a substrate, the dye-receiving layer or At least one electrolyte metal provided on the one side or the other side and at least one other layer containing a resin is selected from organic or inorganic potassium salt, barium salt, sodium salt or strontium salt in the matrix It contains a metal ion conductive agent in which a salt is dispersed.

  The present invention is also a method for producing a thermal transfer image-receiving sheet, which comprises a step A of providing a dye-receiving layer mainly comprising a binder resin having dye-dyeing properties and containing a metal ion conductive agent on one surface of a substrate. Or a step A-1 of providing a dye-receiving layer mainly composed of a binder resin having dye-dyeing property on one surface of the substrate, and a constituent resin and a metal ion conductive agent on the one surface or the other surface; A step A-2 of providing at least one other layer containing the metal ion conductive agent selected from organic or inorganic potassium, barium, sodium, or strontium salts in the matrix And at least one electrolyte metal salt dispersed therein.

  In this invention, it is preferable that the said matrix is bridge | crosslinked through the said binder resin or structural resin and isocyanate compound in the same layer.

  Furthermore, in the present invention, it is preferable to use a compound that is liquid at room temperature as the matrix.

  As described above, the present invention includes an organic or inorganic potassium salt, barium salt, sodium salt, or strontium salt as an electrolyte metal salt to provide conductivity equal to or higher than that of a lithium ion conductive resin. Occurrence of white spots due to the adhesion of dust or the like to the surface of the thermal transfer image receiving sheet due to the above-mentioned charging, a decrease in resolution due to generation of wrinkles of the thermal transfer sheet in contact with the thermal transfer image receiving sheet, and adhesion between the thermal transfer image receiving sheet and the thermal transfer sheet It is possible to prevent a conveyance failure based on the above.

  Moreover, this invention makes it possible to disperse | distribute a metal ion conductive material more uniformly, for example in binder resin which comprises a dye receiving layer, by using a liquid compound as a matrix of a metal ion conductive agent. As a result, the above-described unevenness of the image highlight portion can be prevented. Furthermore, by providing desired conductivity, the above-described resolution is based on the occurrence of white spots due to the adhesion of dust or the like to the surface of the thermal transfer image receiving sheet due to electrostatic charging, and the occurrence of wrinkles on the thermal transfer sheet that contacts the thermal transfer image receiving sheet. It is possible to prevent a decrease and a conveyance failure due to sticking between the thermal transfer image receiving sheet and the thermal transfer sheet.

  Furthermore, even when a metal ion conductive agent is contained in a layer other than the above-described dye-receiving layer, the matrix of the metal ion conductive agent is uniformly dispersed in the matrix resin constituting the layer, so that a uniform conductive property can be obtained. Passes can be formed, and antistatic performance can be equalized and homogenized.

  In addition, when the liquid compound as the above matrix is used alone with the metal ion conductive agent, for example, when the liquid compound is added alone to the dye receiving layer together with the metal ion conductive agent, the liquid compound is mainly made of paper or the like. The base material oozes out and the base material is seen through from the outside due to the so-called oil paper effect, which causes problems such as deterioration in design. However, such a problem can also be prevented by crosslinking such a matrix with a binder resin constituting the dye-receiving layer via an isocyanate compound.

  Further, even when the metal ion conductive agent is contained in a layer other than the dye-receiving layer as described above, the matrix of the metal ion conductive agent is cross-linked with the base material resin constituting the layer through the isocyanate compound. By doing so, bleeding out of the metal ion conductive agent can be prevented, unevenness and bleeding at the time of printing can be prevented, and deterioration in conductivity can be prevented over a long period of time. Further, by fixing the matrix in a uniformly dispersed state, the conductive paths are formed more evenly and the conductivity is improved.

  Embodiments of the present invention will be described below.

  The term “normal temperature” used in the claims and the specification of the present application refers to a temperature within a range of 15 ° C. to 30 ° C. which is a general manufacturing environment.

  The term “liquid” refers to a liquid that does not have a certain form, is fluid, and has a substantially constant volume.

  Examples of the substrate that is a support used in the thermal transfer image-receiving sheet of the present invention include art paper, coated paper, cast coated paper, cellulose fiber paper, high-quality paper, or synthetic paper in which a resin film is laminated on one or both sides thereof. Paper bases, polyolefins such as polyethylene and polypropylene, film bases such as polyvinyl chloride, polyester, polystyrene, polycarbonate, nylon, etc. are preferably used, and at least one layer is a resin and an inorganic pigment. A film having a multilayer structure, which is a foamed layer having voids (holes) produced by biaxial stretching with the above as the main component, is more preferably used. However, the present invention is not limited to the use of the above-described substrate, and for example, production of an OHP thermal transfer image receiving sheet using a transparent polyester sheet as a substrate is also included in the scope of the present invention.

  The thickness of the substrate is preferably 80 μm to 300 μm, more preferably 200 μm to 250 μm. When the thickness is less than 80 μm, if an attempt is made to obtain the required rigidity, the elasticity in the thickness direction is reduced, and the print density may be reduced. On the other hand, when the thickness exceeds 300 μm, the economical efficiency is more serious than the improvement of the performance as a support.

  Binder resins having dyeing properties for forming a dye-receiving layer provided on a substrate include polyolefin resins such as polyethylene and polypropylene; vinyl halide resins such as polyvinyl chloride; polyvinyl acetate and polyacrylic esters Examples include vinyl resins such as polyethylene terephthalate and polyester resins such as polybutylene terephthalate; polystyrene resins; polyamide resins; copolymers of olefins such as ethylene and propylene and other vinyl monomers; polycarbonates and the like. However, it is not limited to these.

  To these resins, add antioxidants, ultraviolet absorbers, light stabilizers, fluorescent brighteners, or pigments and fillers such as titanium oxide, zinc oxide, kaolin clay, and calcium carbonate as necessary. Can do.

  The dye-receiving layer can be formed by using a gravure printing method, a screen printing method, a reverse solution obtained by dissolving a solution obtained by adding the necessary additives to these resins in a suitable organic solvent, or a dispersion liquid dispersed in an organic solvent or water. The coating can be carried out by coating on a substrate or an intermediate layer provided on the substrate by a known coating film forming means such as a roll coating method, and then drying.

  The thickness of the dye receiving layer is not particularly limited, but is generally 1 μm to 10 μm.

  If necessary, an intermediate layer such as a primer layer, a conductive layer, or an ultraviolet absorbing layer may be provided between the substrate and the dye-receiving layer. Moreover, you may provide suitably back layers, such as a slipping layer and an antistatic layer, in the surface on the opposite side to the dye receiving layer of a base material.

  As the matrix of the metal ion conductive agent used in the present invention, a compound having an ether bond can be mentioned as a suitable one, and in particular, glycols such as ethylene glycol and propylene glycol, ethylene oxide (EO), propylene oxide (PO) and the like. Monomers, polyethylene glycol (PEG) obtained by polymerizing ethylene oxide (EO), propylene oxide (PO), polypropylene glycol (PPG), ethylene oxide-propylene oxide copolymer (poly (EO-PO)), Oligomers and polymers containing dimers, trimers and the like of polyether polyols such as ethylene-ethylene glycol graft copolymers are preferred from the viewpoints of handleability and price.

  The matrix is preferably a liquid compound. By using a liquid compound as the matrix, a more uniform conductive path can be formed by uniformly dispersing, for example, in the binder resin constituting the dye receiving layer.

  For example, in the case of polyethylene glycol (PEG), a liquid polymer can be obtained by setting the molecular weight to about 2000 or less.

Examples of the organic or inorganic electrolyte metal salt dispersed in the metal ion conductive agent include KPF ₆ , KClO ₄ , KBF ₄ , KAsF ₆ , KAlCl ₄ , KCF ₃ SO ₃ , KC ₂ F ₅ SO ₃ , KC _{4. F 9 SO 3, KN (CF} 3 SO 2) 2, KN (C 2 F 5 SO 2) 2, KN (C 4 F 9 SO 2) 2, KC (SO 2 CF 3) 3, KC (C 2 F _{5 SO 2) 3, KC (} C 4 F 9 SO 2) 3; NaPF 6, NaClO 4, NaBF 4, NaAsF 6, NaAlCl 4, NaCF 3 SO 3, NaC 2 F 5 SO 3, NaC 4 F 9 SO 3 _{, NaN (CF 3 SO 2)} 2, NaN (C 2 F 5 SO 2) 2, NaN (C 4 F 9 SO 2) 2, NaC (SO 2 CF 3) 3, NaC (C 2 _{5 SO 2) 3, NaC (} C 4 F 9 SO 2) 3; BaPF 6, BaClO 4, BaBF 4, BaAsF 6, BaAlCl 4, BaCF 3 SO 3, BaC 2 F 5 SO 3, BaC 4 F 9 SO 3 BaN (CF ₃ SO ₂ ) ₂ , BaN (C ₂ F ₅ SO ₂ ) ₂ , BaN (C ₄ F ₉ SO ₂ ) ₂ , BaC (SO ₂ CF ₃ ) ₃ , BaC (C ₂ F ₅ SO ₂ ) _{3, BaC (C 4 F 9} SO 2) 3; SrPF 6, SrClO 4, SrBF 4, SrAsF 6, SrAlCl 4, SrCF 3 SO 3, SrC 2 F 5 SO 3, SrC 4 F 9 SO 3, SrN (CF _{3 SO 2) 2, SrN (} C 2 F 5 SO 2) 2, SrN (C 4 F 9 SO 2) 2, SrC (SO 2 CF 3) 3, SrC _{C 2 F 5 SO 2) 3} , SrC (C 4 F 9 SO 2) 3 and the like are suitably used.

  In addition, the mechanism by which the metal ion conductive agent exhibits conductivity is considered as follows. That is, normally, an electrolyte metal salt such as potassium perchlorate is present in the state of a solid salt in which an anion and a cation are bonded by an ionic bond in the absence of a medium such as water or an organic solvent, and this is simply kneaded into a polymer. Just ionic conductivity is not manifested. In the ion conductive resin, the electrolyte metal salt is first solvated and ionized by an ether enzyme such as polyalkylene glycol as a matrix. The dissociated ionic species are easily moved by molecular vibrations such as polyalkylene glycol, and move toward a corresponding pole when an external electric field is applied to express ionic conduction.

  The content of the electrolyte metal salt in the matrix is preferably 5% by weight or more and 40% by weight or less based on the weight of the matrix. If it is less than 5% by weight, a large amount of metal ion conductive agent must be contained in order to obtain the desired electrical conductivity, which is of course inferior in economic efficiency, especially when it is contained in the dye receiving layer. Tends to be inferior in dyeability due to a decrease in the relative amount of the binder resin. On the other hand, even if it contains electrolyte metal ion salt in an amount exceeding 40% by weight, it does not lead to improvement in the conductive performance of the metal ion conductive agent, resulting in poor economic efficiency.

Of the above-mentioned electrolyte metal salts, perchlorate metal salts such as KClO ₄ are oxidizing solids belonging to the first class of dangerous materials stipulated in the Fire Service Law, and are mixed with combustible materials and decomposed by heat or the like. There is a risk of causing extremely intense combustion. Considering this point, the content of these perchloric acid metal salts is preferably 20% by weight or less, more preferably 15% by weight or less based on the weight of the matrix.

In addition, fluorine-containing organic compounds such as NaCF ₃ SO ₃ are generally expensive, and blending in a large amount is disadvantageous in terms of cost, but has an advantage of improving thermal stability. Therefore, when using a perchloric acid metal salt as the electrolyte metal salt, it is preferably used in combination with a fluorine-containing organic compound, and in that case, from the viewpoint of balancing cost and improvement in thermal stability, The perchloric acid metal salt and the fluorine-containing organic compound are preferably blended in a mass ratio of 1: 5 to 5: 1, and more preferably in a mass ratio of 1: 3 to 3: 1.

  The metal ion conductive agent can be contained uniformly or non-uniformly (for example, with a concentration gradient) in the entire dye-receiving layer, as well as the surface portion of the dye-receiving layer, the dye-receiving layer and the substrate. And an intermediate layer provided between the sliding layer and the substrate, for example, an intermediate layer provided between the sliding layer and the substrate.

In that case, the blending amount of the metal ion conductive agent with respect to the resin constituting each layer is 0.1 to 30 parts by weight with respect to 100 parts by weight of the constituent resin of each layer (for example, the binder resin of the dye receiving layer). It is not limited to this, and the blending amount may be adjusted appropriately so that the surface specific resistance of the thermal transfer image-receiving sheet is 1.0 × 10 ¹³ Ω / □ or less, preferably 1.0 × 10 ¹¹ Ω / □ or less. .

  As described above, since the matrix of the metal ion conductive agent used in the present invention has a hydroxyl group at the terminal, bleeding out easily occurs due to the involvement of temperature, humidity and the like. In particular, in the case of a liquid compound, for example, when it is contained in a dye receiving layer, there is a risk of bleeding on the surface. In addition, a problem arises that the base material is seen through due to the so-called oil paper effect that starts to penetrate into the base material. Therefore, for example, when it is contained in the dye-receiving layer, the resin constituting the dye-receiving layer is added to a crosslinking agent (for example, diphenylmethane diisocyanate, isophorone diisocyanate, hexamethylene diisocyanate, phenylene diisocyanate, etc.) such as epoxy and acrylic. It is preferable to add tolylene diisocyanate, propane diisocyanate, hexane diisocyanate, decane diisocyanate, hexanefluoropropane diisocyanate, 1,4-phenylene diisocyanate, etc.) and to crosslink or cure by radiation, heat, moisture, catalyst, or the like.

  In addition, when the configuration disclosed in the above-mentioned document 2 is adopted, or when a general antistatic agent or surfactant is added to the receiving layer, it adversely affects light resistance, and in particular, a specific color (for example, , Yellow and cyan) are greatly faded, and particularly when a portrait photograph or a landscape photograph taken with a digital camera is printed, there is a problem that the color balance after the fade is deteriorated. However, by adopting the configuration according to the present invention, it is possible to greatly reduce the adverse effect on light resistance, and even if the color fades, each color constituting the image will fade with a good balance. This is particularly effective when printing photographs.

  EXAMPLES Hereinafter, although this invention is demonstrated based on an Example, these Examples are illustrations and this invention is not limited to these Examples. In the following description, “part” means “part by weight”.

[Reference example]
Biaxially stretched polypropylene on both sides of commercially available A2 coated paper (Mitsubishi Paper Co., Ltd .; thickness 110 μm; basis weight 127 g / cm ² ) via urethane adhesive (coating amount: 5 g / m ² ). A film (P4256 (trade name); manufactured by Toyobo Co., Ltd .; thickness: 40 μm) was laminated by dry lamination to obtain a substrate.
Then the following composition:
Polyester resin (Toyobo Co., Ltd .; Byron 200 (trade name)) 10 parts Isocyanate compound (Daiichi Seika Kogyo Co., Ltd .; Crossnate D70 (trade name)) 5 parts Toluene / MEK (weight ratio 1: 1) ) 100 parts of coating solution 1 was applied to one side of the substrate with a Mayer bar so as to be 2.5 g / cm ² when dried, and then dried in an oven at 100 ° C. for 30 minutes to form a dye receiving layer And a thermal transfer image receiving sheet was obtained.
The obtained thermal transfer image-receiving sheet was left for 48 hours in an environment of 60 ° C. and 80% humidity, and then left for 12 hours in an environmental condition (hereinafter referred to as normal conditions) of 25 ° C. and 50% humidity. For samples that were allowed to stand for 12 hours under environmental conditions (hereinafter referred to as low humidity conditions) at 5 ° C and 0% humidity, use a super-insulation / microammeter (DSM-8140 (trade name)) manufactured by Toa DK Corporation. When the surface resistivity was measured, all showed a surface resistivity of 10 × 10 ¹⁴ Ω / □ or more.

[Example 1]
Biaxially stretched polypropylene on both sides of commercially available A2 coated paper (Mitsubishi Paper Co., Ltd .; thickness 110 μm; basis weight 127 g / cm ² ) via urethane adhesive (coating amount: 5 g / m ² ). A film (P4256 (trade name); manufactured by Toyobo Co., Ltd .; thickness: 40 μm) was laminated by dry lamination to obtain a substrate.
Then the following composition:
Polyester resin (Toyobo Co., Ltd .; Byron 200 (trade name)) 10 parts Isocyanate compound (Daiichi Seika Kogyo Co., Ltd .; Crossnate D70 (trade name)) 5 parts Metal ion conductor (Nippon Carlit Co., Ltd.) ); PEL-RX (trade name);
Matrix: ethylene oxide-propylene oxide copolymer (poly (EO-
PO); molecular weight 1300); electrolyte metal salt: organoboron complex potassium salt; weight ratio of matrix to electrolyte metal salt = 8: 2) 1.2 parts Cross-linking aid (triethylenediamine) 0.0006 parts Toluene / MEK (Weight ratio 1: 1) The coating liquid 2 having 100 parts was applied to one side of the substrate so as to be 2.5 g / cm ² when dried with a Mayer bar, and then in an oven under conditions of 100 ° C. × 30 minutes. The dye receiving layer was formed by drying to obtain a thermal transfer image receiving sheet.

<Antistatic performance test: Measurement of surface resistivity after standing at high temperature and high humidity>
As in the above Reference Example, the obtained thermal transfer image-receiving sheet was allowed to stand for 48 hours in an environment of 60 ° C. and 80% humidity, and then for 12 hours under an environmental condition (normal conditions) of 25 ° C. and 50% humidity. For the samples left standing and the samples left for 12 hours under environmental conditions (low humidity conditions) of temperature 5 ° C and humidity 0%, super insulation / microammeter (DSM-8140 (trade name)) manufactured by Toa DKK Co., Ltd. Used to measure the surface resistivity and confirm the antistatic performance. Table 1 shows the measured surface resistivity.
Furthermore, in order to investigate the resistance of the antistatic performance to humidity change, the ratio (D value) of (surface specific resistance measured under low humidity conditions) / (surface specific resistance measured under normal conditions) was determined and evaluated as follows. Evaluation was made according to criteria. The evaluation results are shown in Table 1.
<Evaluation criteria>
◎ (good): D value is less than 10 ¹ Δ (possible): D value is 10 ¹ or more and less than 10 ² × (impossible): D value is 10 ² or more

<Evaluation of transfer image quality after standing under high temperature and high humidity conditions>
The obtained thermal transfer image receiving sheet was cut into a size of 100 mm × 140 mm. Each cut image-receiving sheet piece was allowed to stand for 48 hours under conditions of a temperature of 60 ° C. and a humidity of 80%, and then left for 1 hour in an environment of a temperature of 25 ° C. and a humidity of 50% or less. Set a special sublimation thermal transfer ribbon to the sublimation thermal transfer printer CVP-G7 (trade name) manufactured by Sony Corporation, and perform gradation printing of 32 gradations on the image receiving sheet of each measurement sample. It was left for 48 hours under conditions of a temperature of 60 ° C. and a humidity of 80%. Thereafter, the image quality unevenness and bleeding of each print were visually evaluated. The evaluation criteria were as follows. The results are shown in Table 1. Note that the evaluation was performed so that the region having a low density changed from the region having a low density to the region having a high density as the gray level was shifted from 1 to 32.
<Evaluation criteria>
◎ (excellent): There was no unevenness or bleeding in all gradations.
○ (Good): Although there was some unevenness in the first to second gradations, there was no other gradation. Or although there was a part which can confirm a blur, it was a level which is satisfactory practically.
X (impossible): There was unevenness even after the third gradation. Alternatively, a level of bleeding that has a practical problem was confirmed.

<Evaluation of design properties of support>
The base material of the obtained thermal transfer image-receiving sheet was visually observed and evaluated according to the following evaluation criteria. The evaluation results are shown in Table 1.
<Evaluation criteria>
○ (Yes): There was no change compared to before application of the receiving layer.
X (impossible): There was a portion that was seen through compared to before application of the receiving layer.

<Evaluation of light resistance>
A xenon fade meter (manufactured by Suga Test Instruments Co., Ltd .; black panel) was obtained by printing a human photograph taken with a digital camera (manufactured by Sony Corporation; Cybershot (trade name)) on the obtained thermal transfer image-receiving sheet. Irradiated at an integrated irradiance of 90 MJ / m ² using a temperature of 60 ° C .; test surface irradiance: 60 W / m ² ), visually observed for fading on the appearance of the sample after irradiation, and evaluated according to the following evaluation criteria did. The evaluation results are shown in Table 1.
<Evaluation criteria>
○ (possible): Fading is seen in the skin color of the person, but the balance of each color is maintained.
X (impossible): Fading is seen in the skin color of the person, and redness is strong and the balance of each color is lost.

[Examples 2 to 5]
The electrolyte metal salt is not the organic boron complex potassium used in Example 1, but NaClO ₄ (Example 2), BaClO ₄ (Example 3), SrN (CF ₃ SO ₂ ) ₂ (Example 4), and KPF, respectively. _{6 A} thermal transfer image-receiving sheet was obtained in the same manner as in Example 1 except that the metal ion conductive agent (Example 5) was used.

[Example 6]
Instead of the metal ion conductive agent used in Example 1, another metal ion conductive agent (matrix: ethylene oxide-propylene oxide copolymer (poly (EO-PO); molecular weight 2000); electrolyte metal salt: potassium perchlorate (KClO ₄ ) and potassium trifluoromethanesulfonate (KCF ₃ SO ₃ ) in a 5: 1 weight ratio; weight ratio of matrix to electrolyte metal salt = 85: 15) Thus, a thermal transfer image receiving sheet was obtained.

[Example 7]
A thermal transfer image-receiving sheet was obtained in the same manner as in Example 1 except that a solid ethylene oxide-propylene oxide copolymer (poly (EO-PO)) having a molecular weight of 2500 was used as the matrix of the metal ion conductive agent used in Example 1. It was.

[Example 8]
Instead of the coating liquid 2 used in Example 1, the following composition:
Polyester resin (Toyobo Co., Ltd .; Byron 200 (trade name)) 15 parts Metal ion conductor (Nihon Carlit Co., Ltd .; PEL-RX (trade name);
Matrix: ethylene oxide-propylene oxide copolymer (poly (EO-
PO); molecular weight 1300); electrolyte metal salt: potassium organoboron complex; weight ratio of matrix to electrolyte metal salt = 8: 2) 1.2 parts toluene / MEK (weight ratio 1: 1) 100 parts coating solution A thermal transfer image receiving sheet was obtained in the same manner as in Example 1 except that No. 3 was used.

[Comparative Example 1]
Instead of the coating liquid 3 used in Example 8, the following composition:
Polyester resin (Toyobo Co., Ltd .; Byron 200 (trade name)) 15 parts Lithium ion conductive resin (Nihon Carlit Co., Ltd .; PEL-AK-1 (trade name)
Matrix resin: ethylene oxide-propylene oxide copolymer (poly
(EO-PO); molecular weight 1300); electrolyte lithium salt: lithium trifluoromethanesulfonate (LiCF ₃ SO ₃ ); weight ratio of matrix resin to electrolyte lithium salt =
8: 2) 0.6 part Toluene / MEK (weight ratio 1: 1) A thermal transfer image-receiving sheet was obtained in the same manner as in Example 8 except that 100 parts of the coating liquid 4 was used.

[Comparative Example 2]
Thermal transfer image receiving in the same manner as in Example 1 except that sorbitan sesquiolate (product of Kao Corporation; trade name: Emanon S-10V), which is a surfactant, was used instead of the metal ion conductive agent used in Example 1. A sheet was obtained.

  The same measurements and evaluations as in Example 1 were performed for the thermal transfer image-receiving sheets obtained in Examples 2 to 8 and Comparative Examples 1 and 2. The results are shown in Table 1.

  As described above in detail, according to the present invention, there is no unevenness in the highlight portion of an image, and the thermal transfer image-receiving sheet having the same or better conductivity as that using a conventional lithium ion conductive resin and its production A method can be provided.

Claims (9)

  A thermal transfer image-receiving sheet having a dye-receiving layer mainly composed of a binder resin having a dye-dyeing property on one side of a substrate, the resin being provided on the dye-receiving layer or the one side or the other side At least one other layer containing a metal ion conductive agent in which at least one electrolyte metal salt selected from an organic or inorganic potassium salt, barium salt, sodium salt or strontium salt is dispersed in a matrix. A thermal transfer image-receiving sheet.   The thermal transfer image-receiving sheet according to claim 1, wherein the matrix is crosslinked through an isocyanate compound and a resin constituting the binder resin or the other layer in the same layer.   2. The matrix is at least one selected from ethylene glycol, propylene glycol, ethylene oxide, propylene oxide, polyethylene glycol, polypropylene glycol, ethylene oxide-propylene oxide copolymer, and ethylene-ethylene glycol graft copolymer. Or the thermal transfer image receiving sheet of 2. The electrolyte metal salt is KPF ₆ , KClO ₄ , KBF ₄ , KAsF ₆ , KAlCl ₄ , KCF ₃ SO ₃ , KC ₂ F ₅ SO ₃ , KC ₄ F ₉ SO ₃ , KN (CF ₃ SO ₂ ) ₂ , KN (C ₂ F ₅ SO ₂ ) ₂ , KN (C ₄ F ₉ SO ₂ ) ₂ , KC (CF ₃ SO ₂ ) ₃ , KC (C ₂ F ₅ SO ₂ ) ₃ , KC (C ₄ F ₉ SO ₂ ) ₃ ; NaPF ₆ , NaClO ₄ , NaBF ₄ , NaAsF ₆ , NaAlCl ₄ , NaCF ₃ SO ₃ , NaC ₂ F ₅ SO ₃ , NaC ₄ F ₉ SO ₃ , NaN (CF ₃ SO ₂ ) ₂ , NaN (C _{2 5 SO 2) 2, NaN (} C 4 F 9 SO 2) 2, NaC (CF 3 SO 2) 3, NaC (C 2 F 5 SO 2) 3, NaC (C 4 F 9 SO 2) 3; _{aPF 6, BaClO 4, BaBF 4} , BaAsF 6, BaAlCl 4, BaCF 3 SO 3, BaC 2 F 5 SO 3, BaC 4 F 9 SO 3, BaN (CF 3 SO 2) 2, BaN (C 2 F 5 SO ₂ ) ₂ , BaN (C ₄ F ₉ SO ₂ ) ₂ , BaC (CF ₃ SO ₂ ) ₃ , BaC (C ₂ F ₅ SO ₂ ) ₃ , BaC (C ₄ F ₉ SO ₂ ) ₃ ; SrPF ₆ , SrClO _{4, SrBF 4, SrAsF 6,} SrAlCl 4, SrCF 3 SO 3, SrC 2 F 5 SO 3, SrC 4 F 9 SO 3, SrN (CF 3 SO 2) 2, SrN (C 2 F 5 SO 2) 2, SrN (C ₄ F ₉ SO ₂ ) ₂ , SrC (CF ₃ SO ₂ ) ₃ , SrC (C ₂ F ₅ SO ₂ ) ₃ , SrC (C ₄ F ₉ SO ₂ ) The thermal transfer image-receiving sheet according to any one of claims 1 to 3 is at least one selected from the group consisting of _3.   A method for producing a thermal transfer image-receiving sheet, comprising a step A of providing a dye-receiving layer mainly comprising a binder resin having dye-dyeing properties and containing a metal ion conductive agent on one surface of a substrate; Step A-1 for providing a dye-receiving layer mainly composed of a binder resin having dye-dyeing property on the surface and at least one containing a constituent resin and a metal ion conductive agent on the one surface or the other surface Step A-2 for providing another layer, wherein the metal ion conductive agent is at least one electrolyte metal selected from an organic or inorganic potassium salt, barium salt, sodium salt, or strontium salt in a matrix A production method, wherein the salt is dispersed.   6. The method for producing a thermal transfer image receiving sheet according to claim 5, further comprising a step of crosslinking the matrix via an isocyanate compound with the binder resin in the same layer or the resin constituting the other layer.   The method for producing a thermal transfer image receiving sheet according to claim 5 or 6, wherein a compound that is liquid at room temperature is used as the matrix.   6. The matrix is at least one selected from ethylene glycol, propylene glycol, ethylene oxide, propylene oxide, polyethylene glycol, polypropylene glycol, ethylene oxide-propylene oxide copolymer, and ethylene-ethylene glycol graft copolymer. The manufacturing method of the thermal transfer image receiving sheet as described in any one of -7. The electrolyte metal salt is KPF ₆ , KClO ₄ , KBF ₄ , KAsF ₆ , KAlCl ₄ , KCF ₃ SO ₃ , KC ₂ F ₅ SO ₃ , KC ₄ F ₉ SO ₃ , KN (CF ₃ SO ₂ ) ₂ , KN _{(C 2 F 5 SO 2)} 2, KN (C 4 F 9 SO 2) 2, KC (SO 2 CF 3) 3, KC (C 2 F 5 SO 2) 3, KC (C 4 F 9 SO 2) ₃ ; NaPF ₆ , NaClO ₄ , NaBF ₄ , NaAsF ₆ , NaAlCl ₄ , NaCF ₃ SO ₃ , NaC ₂ F ₅ SO ₃ , NaC ₄ F ₉ SO ₃ , NaN (CF ₃ SO ₂ ) ₂ , NaN (C _{2 5 SO 2) 2, NaN (} C 4 F 9 SO 2) 2, NaC (SO 2 CF 3) 3, NaC (C 2 F 5 SO 2) 3, NaC (C 4 F 9 SO 2) 3; _{aPF 6, BaClO 4, BaBF 4} , BaAsF 6, BaAlCl 4, BaCF 3 SO 3, BaC 2 F 5 SO 3, BaC 4 F 9 SO 3, BaN (CF 3 SO 2) 2, BaN (C 2 F 5 SO _{2) 2, BaN (C 4} F 9 SO 2) 2, BaC (SO 2 CF 3) 3, BaC (C 2 F 5 SO 2) 3, BaC (C 4 F 9 SO 2) 3; SrPF 6, SrClO _{4, SrBF 4, SrAsF 6,} SrAlCl 4, SrCF 3 SO 3, SrC 2 F 5 SO 3, SrC 4 F 9 SO 3, SrN (CF 3 SO 2) 2, SrN (C 2 F 5 SO 2) 2, SrN (C ₄ F ₉ SO ₂ ) ₂ , SrC (SO ₂ CF ₃ ) ₃ , SrC (C ₂ F ₅ SO ₂ ) ₃ , SrC (C ₄ F ₉ SO ₂ ) _The method for producing a thermal transfer image receiving sheet according to any one of claims 5 to 8, which is at least one selected from the group consisting of ₃ .