JPS637972A - Sheet for receiving thermal transfer - Google Patents

Abstract

PURPOSE:To enhance the light fastness and weatherability of an image formed by the transfer of a dye, by containing a modified polyester resin synthesized using long chain dicarboxylic acid as a dicarboxylic acid component in a receiving layer. CONSTITUTION:A receiving layer 3 is constituted so as to receive an image of a dye transferred from a thermal transfer sheet, for example, a sublimable disperse dye to hold the same. The receiving layer 3 is constituted so as to contain a modified polyester resin containing a long chain methylene group. MW of the modified polyester resin is pref. 10,000-30,000 and the polymerization degree thereof is pref. about 100-200.

Description

Detailed Description of the Invention (Industrial Application Field) The present invention is used in combination with a thermal transfer sheet, and has excellent dye dyeing properties, as well as improved light resistance and weather resistance, especially light resistance, of the formed image. The present invention relates to a heat transfer sheet with excellent properties.

(Prior art) A thermal transfer sheet having a dye layer containing a sublimable disperse dye is heated in spots according to an image signal using a thermal head, etc., and an image made of the dye transferred to the surface of resin-coated paper is created. Attempts are being made to form a

However, with conventional thermal transfer sheets, the images formed thereon do not have sufficient light resistance and weather resistance, and once formed, the clarity of the images may decrease or the images may change color. this is,
This is thought to be because the dye transferred by a thermal head or the like exists near the surface of the receiving layer and is therefore easily affected by light and humidity.

(Problems to be Solved by the Invention) Therefore, the present invention aims to eliminate the above-mentioned drawbacks of the prior art and improve the light resistance and weather resistance of images formed by dye migration.

Through research conducted by the present inventors, it has been discovered that light resistance and weather resistance are significantly improved by constructing the receptor layer using a modified polyester resin containing long-chain methylene groups, and this has led to the completion of the present invention. It's arrived.

In the present invention, a thermal transfer sheet is used in combination with a thermal transfer sheet having a dye layer containing a dye that is transferred by melting or sublimation by heat, and the dye that transfers from the thermal transfer sheet is transferred to the surface of a sheet-like base material. 1. A thermal transfer sheet having a receiving layer that receives the heat transfer sheet, wherein the receiving layer contains a modified polyester resin synthesized using a long-chain dicarboxylic acid as a dicarboxylic acid component. This makes it possible to overcome the drawbacks of the conventional techniques described above.

The thermal transfer sheet 1 of the present invention includes, for example, a sheet-like base material 2
It has a structure having a receptive layer 3 thereon, and an intermediate layer 4 is provided between the sheet-like base material 2 and the receptive layer 3 if necessary. The receiving layer 3 may be provided on one side of the sheet-like base material 2.

(Sheet-like base material) As the sheet-like base material 2, ■synthetic paper (polyolefin type, polystyrene type, etc.), ■high-quality paper, art paper, coated paper, cast-coated paper, wallpaper-backed paper, synthetic resin or emulsion-impregnated paper. , synthetic rubber latex-impregnated paper, synthetic resin-loaded paper, paperboard, or natural fiber paper such as cellulose fiber paper; *Various plastic films or sheets such as polyolefin, polyvinyl chloride, polyethylene terephthalate, polystyrene, methacrylate, and polycarbonate. Can be used. Among these, synthetic paper (2) is preferable because it has a microvoid layer with low thermal conductivity (in other words, high heat insulation) on its surface;
A laminate made of any combination of ~■ can also be used.6 Representative examples of laminates include cellulose fiber paper, synthetic paper,
Alternatively, a laminate of cellulose fiber paper and a plastic film or sheet may be used. Among these, the laminate of cellulose fiber paper and synthetic paper has a structure in which the cellulose fiber paper does not compensate for the thermal instability (expansion and contraction, etc.) of the synthetic paper.
The low thermal conductivity of synthetic paper makes it possible to exhibit high printing thermal sensitivity, and in order to balance the front and back sides of the laminate in this combination, synthetic paper - cellulose fiber -
It is best to use a three-layer laminate of synthetic paper, which can reduce curling caused by printing.

As the synthetic paper used for the above-mentioned laminate, generally any material can be used as long as it can be used as a base material for a thermal transfer sheet, but in particular synthetic paper with a paper-like layer having micropores is used. (For example, commercially available synthetic paper: Yupo: manufactured by Oji Yuka Synthetic Paper) is desirable.The fine pores in the above paper-like layer are formed by, for example, stretching a synthetic resin in a state containing a fine filler. can do. Thermal transfer sheet constructed using the synthetic paper provided with the above-mentioned fine pores has the effect that when an image is formed by thermal transfer, the image density is high and there is no variation in the image. It is thought that the fine pores have a heat insulating effect, the thermal energy efficiency is good, and the fine pores have good adhesive properties, which contribute to the receiving layer provided on the synthetic paper and on which images are formed. . Moreover, it is also possible to provide the paper-like layer containing the above-mentioned micropores directly on the surface of a core material such as cellulose fiber paper.

A plastic film can be used in addition to the cellulose fiber paper in the laminate, and a laminate of the cellulose fiber paper and a plastic film can also be used.

Examples of methods for bonding synthetic paper and cellulose fiber paper include bonding using a conventionally known adhesive, bonding using an extrusion lamination method, and bonding by thermal adhesive. The method for attaching the plastic film is the lamination method, which also serves as the formation of the plastic film at the same time.
Examples include pasting by a calendar method or the like. The above-mentioned pasting means is washed as appropriate depending on the material of the synthetic paper and the material to be pasted. Specific examples of the adhesive include emulsion adhesives such as ethylene-vinyl acetate copolymer and polyvinyl acetate;
Examples include water-soluble adhesives such as polyester containing carboxyl groups, and examples of adhesives for lamination include organic solvent solutions such as polyurethane and acrylic. Adhesives include:

(Receiving Layer) The material constituting the receiving layer 3 is a layer for receiving (image receiving) an image of a dye transferred from a thermal transfer sheet, such as a sublimable disperse dye, and for maintaining the image formed by reception.

In the present invention, the receptor layer 3 is comprised of a modified polyester resin containing long-chain methylene groups.

The molecular weight of the modified polyester resin is preferably about 10,000 to 30,000, and the degree of polymerization is about 100 to 200.

The reason why the weather resistance of the dyes is improved when the modified polyester resin has long chain methylene groups is that the number of ester bonds in the polymer is relatively reduced, so the ester bond sites can be stimulated by photoexcitation. This is thought to be because the probability that lubricating oxygen will be generated is reduced, making it difficult for photodecomposition to occur in the presence of oxygen and moisture that cause dye deterioration. In this sense, the methylene group of the dicarboxylic acid (HOOCCCHt )-C0OH (1) (described below) is preferably n≧6, and the upper limit is n≦30. Such long-chain dicarboxylic acids contain 20
It is desirable that it be 100 mol%.

Although it has already been mentioned that the thermal transfer sheet of the present invention has good light resistance, it is particularly good to use a sublimable anthraquinone dye as the dye constituting the thermal transfer sheet.

Sublimable anthraquinone dyes include Solvent Blue 63, 59, 36, 14, 74, Solvent Violet 14, 11° Disper Red 60,
3, Disperse Bioleft 26, Disperse Blue 26, 40, etc. When these dyes are used in combination with modified polyester resin, they have good light resistance.
Almost no fading under 3rd grade irradiation.

Modified polyester resins are therefore synthesized using the following modified acid components.

Modified acid component HOOC (CHz), ICoOH In the formula, n is 6≦n≦30.

Alternatively, as the dicarboxylic acid component, the former (1) containing a methylene group with n<'5 may be used in combination.

Note that each component in the synthesis does not have to be of a single type, and multiple types may be appropriately combined.

The modified polyester resin can also be used in combination with other resins to form the receptor layer.

For example, the following synthetic resins (al to tel) can be used alone or in combination of two or more.

Those with +al ester bond.

Polyester resin (other than phenyl modified), polyacrylic ester resin, polycarbonate resin, polyvinyl acetate resin, styrene acrylate resin, vinyl toluene acrylate resin.

Mountain) Those with urethane bonds.

Polyurethane resin, etc.

Contains an IcI amide bond.

Polyamide resin (nylon).

(Those with dl urea bond.

Urea resin etc.

Tel and other substances with highly polar bonds.

Polycaprolactone resin, polystyrene resin, polyvinyl chloride resin, polyacrylonitrile resin, etc.

For example, the receptor layer 3 is made of a mixed resin of modified polyester and normal polyester resin (not phenyl modified). Saturated polyesters include, for example, Byron 200, Byron 290, Byron 600 (Toyo Casting Co., Ltd.), KA-1038C (Arayo Kagaku Co., Ltd.), and TP22.
0, TP235 (all manufactured by Nippon Gosei), etc. are used.

Alternatively, the receiving layer is composed of a modified polyester resin and a vinyl chloride resin/vinyl acetate copolymer resin. The vinyl chloride/vinyl acetate copolymer resin preferably has a vinyl chloride component content of 85 to 97% by weight and a degree of polymerization of about 200 to 800.The vinyl chloride/vinyl acetate copolymer resin does not necessarily have a vinyl chloride component and vinyl acetate. Not limited to copolymers containing only copolymer components, vinyl alcohol components,
It may also contain a maleic acid component or the like.

The receptor layer 3 may also be composed of a mixed resin of a modified polyester resin and a polystyrene resin, for example, a styrene monomer, such as a single or copolymer of styrene, α-methylstyrene, or vinyltoluene. or an acrylic or methacrylic yarn material made of the styrene monomer and other monomers, such as acrylic ester, methacrylic ester, acrylonitrile, methacrylonitrile, etc.
Alternatively, a styrenic copolymer resin which is a copolymer with maleic anhydride may be mentioned.

When using modified polyester resin and other resins together,
Although it depends on the degree of phenyl modification of the modified polyester resin, it is preferable to use 0 to 100 parts by weight of the other resin per 100 parts by weight of the modified polyester resin. In other words,
When used together as above, total resin weight 100g
The modified polyester resin may account for 50 to 100 g. In any of the above embodiments, the whiteness of the receptor layer 3 is improved to further enhance the clarity of the transferred image, and the surface of the heat transfer sheet is provided with writability. However, a white pigment can be added to the receiving layer 3 for the purpose of preventing the transferred image from being retransferred. As the white pigment, titanium oxide, zinc oxide, kaolin, clay, calcium carbonate, finely powdered silica, etc. are used, and as described above, two or more of these can be used in combination. In addition, in order to further increase the light resistance of the transferred image, an ultraviolet absorber is added to the image-receiving layer.
One or more additives such as a light stabilizer or an antioxidant may be added as necessary. The amounts of these ultraviolet absorbers and light stabilizers added are preferably 0.05 to 10 parts by weight and 0.5 to 3 parts by weight, respectively, per 100 parts by weight of the resin constituting the receiving layer 3.

The thermal transfer sheet of the present invention may contain a release agent in the receptor layer in order to improve the releasability from the thermal transfer sheet. As a mold release agent, polyethylene wax,
Examples include solid waxes such as amide wax and Teflon powder; fluorine-based and phosphoric acid ester-based surfactants; and silicone oil, with silicone oil being preferred.

As the above-mentioned silicone oil, an oily one can be used, but a curable type is preferable. Examples of the curable silicone oil include a reaction-curing type, a photo-curing type, a catalytic-curing type, and a reaction-curing type. As the zero-reaction curing silicone oil, the silicone oil is particularly preferable.
Preferably, an amino-modified silicone oil and an epoxy-modified silicone oil are reacted and cured, and examples of the amino-modified silicone oil include KF-393 and KF-85.
7, KF-858, X-22-3680SX-22-3
80IC (manufactured by Shin-Etsu Chemical Co., Ltd.), etc., and KF-100TS as an epoxy modified silicone oil.
Examples include KF-101, KF-60-164, and KF-103 (manufactured by Shin-Etsu Chemical Co., Ltd.). In addition, KS-7 is a catalyst-curing or photo-curing silicone oil.
05F, KS-770 (catalyst curing silicone oil: Shin-Etsu Chemical type), KS-720, KS-
774 (photocurable silicone oil: manufactured by Shin-Etsu Chemical Co., Ltd.), and the like. The amount of the curable silicone oil added is preferably 0.5 to 30% by weight of the resin constituting the image-receiving layer, and the release agent is dissolved or dispersed in a suitable solvent on a part of the surface of the image-receiving layer 3. After applying the
A mold release agent can be provided by drying or the like.As the mold release agent constituting the mold release agent, a reaction cured product of the above-mentioned amino-modified silicone oil and epoxy-modified silicone oil is particularly preferred.

The thickness of the release agent layer is 0.01 to 5 μm, especially 0.05 to 2
μm is preferred.

Note that if silicone oil is added when forming the receiving layer, the release agent layer can be formed even if the silicone oil bleeds onto the surface after coating and is then cured.

The above-mentioned white pigment, ultraviolet absorption side, light stabilizer, antioxidant, and mold release agent can be applied so as to be included in the receiving layer on one side or both sides, if necessary.

The formation of the receptive layer 3 can be carried out by a known coating or printing method using a receptive layer forming composition obtained by dissolving or dispersing the material for forming the receptive layer on the sheet-like base material 2. , it may be performed by a method in which the image is once formed on a partial carrier different from the sheet-like base material 2 and then transferred onto the sheet-like base material 2 again.

As a partial carrier, a sheet with a releasable surface is used.For example, ■Cellulose fiber paper or synthetic paper with an undercoat layer applied to the surface and then a release silicone layer applied, ■Cellulose fiber On some carriers, such as paper surfaces coated with extrusion polyolefin resins or polyester resins, or plastic films such as polyester films with a release silicone layer applied, etc.
After forming a receptor layer in the same manner as on the sheet-like base material 2, an adhesive layer is formed if necessary. This adhesive layer is used when transferring the image receiving layer onto the sheet-like base material 2.
This is to ensure adhesive strength between the sheet-like base material 2 and the receiving layer 3. In this method, another layer, for example, an intermediate layer imparting cushioning properties, is formed on a portion of the carrier, and the intermediate layer and the receiving layer are transferred onto the sheet-like base material 2 at the same time. If the intermediate layer also serves as an adhesive, the adhesive layer may not be formed on the partial carrier; in any case, the adhesive layer is a sheet-like substrate, Since it is sufficient that the adhesive layer is interposed between the uppermost layer on the temporary carrier and the uppermost layer on the temporary carrier, the adhesive layer is formed on the sheet-like base material 2, and only the receiving layer is placed on the temporary carrier.
Alternatively, the receiving layer and the intermediate layer may be formed in this order and then transferred.

When a method is adopted in which the receptive layer 11I3 is once formed on a temporary carrier and then formed on the sheet-like base material 2 by a transfer method, the surface of the receptive layer formed on the sheet-like base material 2 is
Because the surface condition of the temporary carrier is transferred, it has very good smoothness, and the receiving layer formed directly on the sheet-like base material 2 has a smoothness compared to that obtained by the transfer method. If you want to obtain clearer and more detailed images, it is better to use the transfer method.

The adhesive may be any adhesive that can bond the receptor layer and the base material, such as polyester, polyacrylic ester,
Organic solvent solutions or emulsions of polyurethane, polyvinyl chloride, polyolefin, ethylene-vinyl acetate copolymers, synthetic rubber, etc. can be used. The adhesive may be a thermal adhesive type or a room temperature adhesive type. In the case of a thermal adhesive type, thermal adhesives such as wax, ethylene/vinyl acetate copolymer resin, polyolefin, petroleum-based resin, etc., may be used. Alternatively, sandwich lamination using an extrusion film such as a polyolefin film may be used.

Double-sided tape may be used as an adhesive that also serves as an intermediate layer 1 Double-sided tape is made by impregnating rayon paper with an acrylic adhesive and drying it, and after drying, the double-sided tape has fine pores and is similar to foam stone. It seems that they play an equivalent role.

(Intermediate Layer) The intermediate layer 4 is either a cushioning layer or a porous layer depending on the material it is made of, or may also serve as an adhesive in some cases.

The cushioning layer is 1 defined in JIS-6301.
00% modulus is 100Kg/aJ or less, and if the 100% modulus exceeds 100Kg/aJ, the rigidity is too high, so such a resin is used to form the intermediate layer. However, sufficient adhesion between the thermal transfer sheet and the thermal transfer layer during printing cannot be maintained, and the lower limit of the 100% modulus is actually 0.5 K.
It is about g/-.

Examples of resins that meet the above conditions include the following.

Polyurethane resin Polyester resin Polybutadiene resin Polyacrylate ester resin Epoxy resin Polyamide resin Rosin modified phenol resin Terpene phenol resin Ethylene/vinyl acetate copolymer resin The above resins can be used singly or in combination of two or more. The above resins are relatively sticky, so if there is a problem during processing, inorganic additives,
For example, silica, alumina, clay, calcium carbonate, etc., or amide-based substances such as stearamide may be added.

The cushioning layer can be formed by kneading the resin as described above with a solvent, diluent, etc. along with other additives as necessary to form a paint or ink, and drying it as a coating film using a known coating method or printing method. , its thickness is 0
．． It is about 5 to 50 μm, more preferably about 2 to 20 μm. If the thickness is 0.5 μm, it will not be able to absorb the roughness of the surface of the sheet-like base material provided, and therefore it will not be effective;
If it exceeds this value, not only will the effect not be improved, but the receiving layer portion will become too thick and protrude, causing trouble when winding or stacking, and is not economical.

Formation of such an intermediate layer improves the adhesion between the thermal transfer sheet and the sheet to be thermally transferred, probably because the intermediate layer itself has low rigidity and is deformed by pressure during printing. It is presumed that this type of resin usually has a low glass transition point or softening point, and the thermal energy applied during printing causes the rigidity to decrease even more than at room temperature, making it easier to deform. .

The porous layer 3 is composed of: (1) a synthetic resin emulsion such as polyurethane, a synthetic rubber latex such as methyl methacrylate-butadiene, which is bubbled by mechanical stirring, and then applied onto the base material 2 and dried; (2) the above synthetic resin emulsion; , a liquid obtained by mixing the synthetic rubber latex with a foaming agent is applied to the base material 2.
The layer coated on top and dried, ① A liquid mixture of a foaming agent mixed with a synthetic resin such as PVC plastisol or polyurethane or a synthetic rubber such as styrene-butadiene is applied onto the base material 2 and foamed by heating. layer, ■ a solution of a thermoplastic resin or synthetic rubber dissolved in an organic solvent, and a solution that evaporates more easily than the organic solvent (and is compatible with the organic solvent and soluble in the thermoplastic resin or synthetic rubber); A mixed solution with a non-solvent (including one mainly composed of water) is applied onto the base material 2 and dried to form a microporous layer, etc., which forms a micro-aggregated film. Used. Above ■
Since the bubbles in the layer ~■ are large, if a solution for forming the receptive layer 3 is applied on the layer and dried, there is a risk that the surface of the receptive layer 3 formed by drying may become uneven. . Therefore, in order to obtain a surface of the receptor layer 3 with small irregularities and on which a highly uniform image can be transferred, it is preferable to provide the microporous layer (2) above as the porous layer.

The thermoplastic resin used for forming the above microporous layer includes saturated polyester, polyurethane,
Vinyl chloride/vinyl acetate copolymers, cellulose acetate propionate, etc. may be mentioned, and the synthetic rubbers that can be used similarly include styrene-butadiene, isoprene, urethane, and the like. Moreover, the material used in forming the microporous layer is 4! A variety of Il solvents and non-solvents are possible, but typically
Hydrophilic solvents such as methyl ethyl ketone and alcohol are used as the organic solvent, and water is used as the non-solvent.

The thickness of the porous layer in the present invention is preferably 3 μm or more, particularly preferably 5 to 20 μm. If the porous layer has a thickness of 3 IIm and is not grooved, the cushioning and heat insulation effects will not be exhibited.

Although the explanation has been complicated, as mentioned in the explanation of the method for forming the receptor layer, the intermediate layer may also serve as an adhesive in some cases.

The above-mentioned intermediate layer may be provided on both sides of the non-thermal transfer sheet when the receiving layer is provided on both sides, or may be provided on only one side.

In order to suppress the generation of static electricity during the processing of the thermal transfer sheet or when it runs in a printer, an antistatic agent may be contained in the receptor layer on at least one side or on the surface of the receptor layer. Examples of antistatic agents include surfactants such as cationic surfactants (e.g., quaternary ammonium salts, polyamine derivatives, etc.), anionic surfactants M (e.g., alkyl phosphates, etc.), and amphoteric surfactants. Alternatively, nonionic surfactants may be mentioned.

The antistatic agent may be applied to the surface of the receptor layer by gravure coating, bar coating, etc. (or may be kneaded into the resin of the receptor layer and transferred to the surface of the receptor layer during coating and drying of the receptor layer).

A cationic acrylic polymer can also be used as an antistatic agent to be mixed with the receptor layer resin.

(Actions and Effects of the Invention) In the thermal transfer sheet of the present invention, the receiving layer thereof is a modified polyester synthesized using a polyol containing a phenyl group and a long-chain dicarboxylic acid.

By using resin, the image formed by printing with a thermal head in combination with a thermal transfer sheet has a high density due to the polyol component, and the color does not change even after long-term storage due to the dicarboxylic acid component. The clarity does not deteriorate due to blurring or blurring, and there is no problem such as discoloration.

(Example) In the following Examples and Comparative Examples, the production of a thermal transfer sheet and a thermal transfer sheet, printing using both sheets, and testing of a thermal transfer sheet were conducted as follows.

6μm thick polyethylene terephthalate film (Toyo Mold: 3-PET) with corona discharge treatment on one side
A thermal transfer layer is formed by applying a thermal transfer layer forming composition having the following composition onto the corona discharge treated surface of the substrate using wire bar coating so that the dry thickness is 1 μm. and silicone oil (X-41) on the back side.
-4003A (manufactured by Shin-Etsu Silicone) was applied with a dropper and spread over the entire surface to form a slippery layer, and then spread over the entire surface to form a cool layer to obtain a thermal transfer sheet.

Composition for forming thermal transfer layer Disperse dye・・・・・・・・・・・・・・・・・・・・・
・・・・・・・・・・・・・・・4 parts by weight (manufactured by Nippon Kayaku: Kayase Soto Blue 714) Ethyl hydroxycellulose・・・・・・5 parts by weight (manufactured by Herkils) Toluene・・・・・・・・・・・・・・・・・・・・・
......40 parts by weight Methyl ethyl ketone...40 parts by weight Dioxane...・・・・・・・・・
......10 parts by weight of heat-transferred synthetic paper with a sheet thickness of 150 μm (manufactured by Oji Yuka: Yupo FPG-1)
50) was used as a base material, a composition for forming a receptor layer having the following composition was coated on the surface of the base material by wire bar coating so that the dry thickness was 4 μm, and after temporary drying with a dryer, 1
This was dried in an oven at 00° C. for 30 minutes to form a receptor layer, and a thermal transfer sheet was obtained.

Composition resin for forming receptor layer・・・・・・・・・・・・・・・・・・・・・
・・・・・・・・・・・・・14 parts by weight Amino-modified silicone oil 1 part by weight (Shin-Etsu Chemical: KF-396) Epoxy-modified silicone oil ...1 part by weight (
Shin-Etsu Chemical: X-22-343) Toluene...
・・・・・・・・・・・・・・・・・・・・・・・・
...42-fold it part methyl ethyl ketone...
......42 parts by weight The above thermal transfer sheet and the sheet to be thermally transferred are stacked so that the thermal transfer layer and the receiving layer are in contact with each other, and the thermal transfer sheet is heated with a thermal head from the base material side of the thermal transfer sheet. Heating is performed at an output IW/dot, a pulse width of 0.3 to 0.45 m/sec, and a dot density of 3 dots/fl, and the cyan disperse dye in the thermal transfer layer of the thermal transfer sheet is transferred to the receiving layer of the thermal transfer sheet. When transferred, a clear cyan image was formed.

Example The following components and trace amounts of calcium acetate and antimony dioxide as catalysts were placed in a Claisen flask reactor equipped with an air cooler, and the temperature was gradually raised to about 150°C in an NZ atmosphere. The reaction was carried out by stirring at this temperature for 1 hour, and then the reaction product was placed in a Pyrex tube equipped with a thermocouple and the OT was completely shut off.
5°C, 0.1-0. A polycondensation reaction was carried out for 2 hours at O5 mmHg to obtain a phenyl-modified polyester resin.

llI superacid component terephthalic acid・・・・・・・・・・・・・・・・・・
・・・・・・40 parts by weight Isophthalic acid・・・・・・・・・
40 parts by weight Nonanedicarboxylic acid 20 parts by weight Polyol component ethylene glycol・・・・・・・・・5
0 parts by weight Bisphenol A・・・・・・・・・・・・・・・
・・・・・・50 parts by weight 11N2 Acid component Terephthalic acid・・・・・・・・・・・・・・・・・・
・・・・・・40 parts by weight Isophthalic acid・・・・・・・・・
......40 parts by weight Dodecanedicarboxylic acid...20 parts by weight Polyol component ethylene glycol... River... ...501
11 parts neopentyl glycol 50
Part by weight ↓ Modified polyester and polystyrene obtained in Example 1
1lfi (manufactured by Rika Percules, Picolastic D12
5) was mixed at a weight ratio of 181.

Comparative example 1 Acid component terephthalic acid・・・・・・・・・・・・・・・・・・
...50 parts by weight isophthalic acid...
・・・・・・・・・・・・・・・501i 1 part polyol component ethylene glycol・・・・・・・・・・・・・・・5
01i 1 part neopentyl glycol・・・・・・・・・
50 parts by weight The resin obtained above was used to form a thermal transfer sheet, and when printing was performed, all of the sheets in Examples 1 to 3 had excellent light resistance and hardly faded. However, the color of the comparative example was significantly faded after tertiary irradiation.

[Brief explanation of drawings]

1 and 2 are cross-sectional views of the thermal transfer sheet of the present invention.

Claims (2)

[Claims] (1) Used in combination with a thermal transfer sheet that has a dye layer containing a dye that transfers by melting or sublimating with heat, and has a receiving layer on the surface of the sheet-like base material that receives the dye that transfers from the thermal transfer sheet. 1. A thermal transfer sheet characterized in that the receiving layer contains a modified polyester resin synthesized using a long chain dicarboxylic acid as a dicarboxylic acid component. (2) The thermal transfer sheet according to claim 1, wherein the receiving layer contains a blend resin of a modified polyester resin and another resin.