JPH03184896A - Thermal transfer sheet and thermal transfer method - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

Detailed Description of the Invention (Industrial Application Field) The present invention relates to a thermal transfer sheet and a thermal transfer method using a sublimable dye (thermally transferable dye), and more specifically to a transfer image having excellent light resistance and fading resistance. The purpose of the present invention is to provide a thermal transfer sheet and a thermal transfer method that can form a thermal transfer sheet.

(Prior art and its problems) Various thermal transfer methods have been known in the past. Among them, a sublimable dye is used as a recording agent, and this is supported on a base sheet such as a polyester film to form a thermal transfer sheet. 2. Description of the Related Art Various methods have been proposed for forming a variety of full-color images on an image-receiving sheet in which four dye-receiving layers are formed on a transfer material that can be dyed with a sublimable dye, such as paper or a plastic film.

In this case, a blink thermal head is used as the heating means, and by heating for a very short time, a large number of three-color or surrounding color dots are transferred to the image-receiving sheet, and the multi-color color dots create a full-color image of the original. It is intended to reproduce.

The images formed in this way are very clear because the coloring material used is dye, and they have excellent transparency, so the images obtained have excellent intermediate color reproducibility and gradation, and are It is similar to images produced by offset printing or gravure printing, and is of high quality comparable to full-color photographic images.

However, since the resulting images are formed from dyes, they generally have inferior light fastness compared to images using pigments, and there is a problem that the images fade or discolor quickly when exposed to direct sunlight. In addition, if there is no direct light, for example, there is a problem that the color may change (dark fading) even indoors, in a file, or when bound in a book. These problems of light resistance and fading can be improved to a certain extent by adding ultraviolet absorbers and antioxidants to the dye-receiving layer of the image-receiving sheet.

However, in the above-mentioned conventional technology, the antioxidant, etc. is uniformly distributed throughout the dye-receiving layer, and most of the transferred dye is present near the surface of the receptor layer, so the antioxidant, etc. There is a problem in that the protective action of dyes is not performed efficiently and the prevention of discoloration and fading is insufficient, and there is a need for a technology that can effectively protect transferred dyes with antioxidants and the like.

As a method to solve these problems, we have developed a method in which UV absorbers are added to the dye layer of the thermal transfer sheet instead of to the image-receiving layer, and the UV absorbers are transferred to the image forming area at the same time as the dye is transferred. The inventor had previously proposed (patent application 1986)
-290101 publication specification).

However, although such a method has considerable effects, it is not necessarily sufficient in forming a color image in which thermal transfer is performed multiple times on the same area of an image-receiving sheet. The reason for this is that during multiple transfers, the UV absorber, etc. that was initially transferred at the same time as the dye penetrates into the dye-receiving layer due to the heating during subsequent transfers, and the actual image is formed. It is presumed that this is due to insufficient concentration on the surface of the image-receiving layer.

Therefore, an object of the present invention is to provide a clear image with sufficient density in a thermal transfer method using a sublimable dye, and to provide the formed image with excellent fastness properties, particularly excellent light fastness and dark fading resistance. An object of the present invention is to provide a thermal transfer sheet and a thermal transfer method that exhibit the following.

(Means for solving problems) The above objects are achieved by the present invention as described below.

That is, the present invention consists of two inventions, and the first invention is a thermal transfer sheet in which a plurality of color dye layers are formed on the surface of a base film, in or on the surface of the dye layer to be transferred last among the dye layers. A thermal transfer sheet is characterized in that a dye stabilizer is contained in the thermal transfer sheet. and the receiving layer of an image receiving sheet provided with a dye receiving layer are stacked facing each other,
A thermal transfer method in which a color image is formed by image-wise heating the back side of a thermal transfer sheet and performing multiple transfers, characterized by transferring a dye stabilizer to the image forming area at the same time as or after the last transfer. This is a thermal transfer method.

(Function) When a color image is formed by multiple thermal transfers, a dye stabilizer is incorporated only in the dye layer used last, or a layer containing the stabilizer is formed on the surface of the dye layer,
By transferring these stabilizers to the imaging area at the same time as or after the final dye transfer, color images with excellent light and fade resistance can be obtained.

(Preferred Embodiments) Next, the present invention will be described in more detail by citing preferred embodiments.

The thermal transfer sheet of the present invention has on one side of the base film,
At least two color dye layers are formed in plane order, and a stabilizer for the dye is included in the last dye layer to be transferred, or a layer of the stabilizer is formed on the dye layer. It is characterized by the fact that For example, if the hue of the dye layer is yellow, magenta, and cyan, and the thermal transfer order is yellow, magenta, and cyan,
The stabilizer is included only in the cyan layer. Furthermore, the present invention also includes the case where a stabilizer layer (not containing dye) is formed in addition to the above-mentioned three color dye layers, and for convenience, this stabilizer layer is referred to as a dye layer in the present invention. It is called. In this case, of course, the stabilizer layer is transferred last.

The base film used in the present invention may be any conventionally known film as long as it has a certain degree of heat resistance and strength. Paper, various processed papers, polyester film, polystyrene film, polypropylene film, polysulfone film, aramid film,
Examples include polycarbonate film, polyvinyl alcohol film, cellophane, etc., and polyester film is particularly preferred.

When the base film as described above has poor adhesion to the dye layer formed on its surface, it is preferable to subject the surface to a primer treatment or a corona discharge treatment.

For the sublimable (thermally transferable) dye layer to be formed on the base film as described above, at least two colors of different hues are selected from the following dyes, and each dye is coated on the base film with an appropriate binder resin. This is a layer supported by

As the dye to be used, any dye used in conventionally known thermal transfer sheets can be effectively used in the present invention.
Not particularly limited. For example, some preferred dyes include magenta dyes, MS Red G, Ma
crolex Red Violet R, Ceres
Red7B, Samaron Red HBSL,
Examples include Re5olin Red F3BS, and
Yellow dyes include Holon Brilliant Yellow 6GL, PTY-52, and Macrolex Yellow 6G.
Examples of cyan dyes include Kayacet Blue 14, Waxolin Blue AP-FW, Holon Brilliant Blue S-R, and MS Blue 100.

As the binder resin for supporting the heat-transferable dye as described above, any conventionally known binder resin can be used, and preferred examples include ethyl cellulose, hydroxyethyl cellulose, ethyl hydroxy cellulose, hydroxypropyl cellulose, methyl cellulose, and acetic acid. Cellulose, cellulose resins such as cellulose acetate butyrate, polyvinyl alcohol, polyvinyl acetate, polyvinyl butyral, polyvinyl acetal, polyvinylpyrrolidone,
Examples include vinyl resins such as polyacrylamide, polyesters, etc. Among these, cellulose resins, polyvinyl acetal resins, polyvinyl butyral resins, polyester resins, etc. are particularly preferred.

The stabilizer used in the present invention includes light energy,
It is a chemical that can prevent the deterioration or decomposition of dyes by absorbing or blocking the deterioration or decomposition effects of dyes, such as thermal energy and oxidation effects.A specific example is oxidation inhibitors, which are conventionally known as additives for synthetic resins. agents, ultraviolet absorbers and light stabilizers.

Antioxidants include phenolics, monophenols,
Examples include primary antioxidants such as bisphenol-based and amine-based antioxidants, and secondary antioxidants such as sulfur-based and phosphorus-based antioxidants, such as Sumilizer BBN-3, Su
milizer BHT, SumilizerGM,
Sumilizer MB, Sumilizer T
PP-R (manufactured by Sumitomo Chemical), Yoshinox 425,
Yoshinox SR (manufactured by Yoshitomi Pharmaceutical), Irgano
It is commercially available under trade names such as x-1081, Irganox-1222 (manufactured by Ciba Geigy), and Mark AO-40 (manufactured by Adeca Argus Chemical), and any of them can be used in the present invention.

Further, examples of the ultraviolet absorber include salicylic acid-based, benzophenone-based, benzotriazole-based, and cyanoacrylate-based ultraviolet absorbers.
nuvin P, Tinuvin 234, Tinu
vin 320, Tinuvin 326, Tinuv
in 327, Tinu-vin 327 (manufactured by Ciba Geigy), Sumisorb 110, Sumis
orb 140 (manufactured by Sumitomo Chemical), Kemi
sorblo, Kemisorb 11. Kemi
sorb 12, emisorb 13 (manufactured by ChemiPro Kasei), Uvinul X-19, Uvinul
Ma2O (manufactured by BASF), Tomisorb 100, Tomisopro 00 (manufactured by Yoshitomi Pharmaceutical ■), l/10sorb-
80, Viosorb 90 (Kyodo Yakuhin Co., Ltd.), and other trade names, and both can be used in the present invention.

Examples of light stabilizers include hindered amines, such as Sanol LS-770, Sanol LS-765, Sanol LS-774 (manufactured by Sanki),
It is commercially available under trade names such as Sumisorb TM-061 (manufactured by Sumira Chemical Co., Ltd.), and any of them can be used in the present invention.

It is preferable that the above-mentioned stabilizer has thermal transferability (thermal transferability) similar to that of sublimation dyes, and for example, does not contain carboxyl groups or sulfonic acid groups, and has a molecular weight of 50.
Preferably, it is 0 or less. If the molecular weight exceeds 500, transferability may be insufficient.

As already explained, the stabilizer is not included in all the dye layers to be formed, but is added only to the dye layer to be transferred last during thermal transfer. According to the research of the present inventor, compared to the lift-up in which stabilizers were added to all the dye layers, 1
Even if the amount of stabilizer 1 added per layer is the same, the effect is almost the same, and therefore the total amount of stabilizer used is 1/2 to 1/4, which is very economical. Further, other problems caused by using a large amount of stabilizer, such as dulling of image tone, do not occur.

The above stabilizers can be used alone or as a mixture, and the amount added is preferably in the range of 10 to 100 parts by weight per 100 parts by weight of the dye. If the amount added is too small, the stabilizing effect on the dye will be insufficient, and if it is too large, problems such as decreased transferability of the dye will occur, which is not preferable.

The dye layer of the thermal transfer sheet of the present invention is basically formed from the above-mentioned materials, but may also contain various conventionally known additives as required.

Such a dye layer is preferably formed by adding the above-mentioned sublimable dye, stabilizer (only the last dye layer), bangu resin, and other optional components to a suitable solvent and dissolving or dispersing each component. A coating material or ink is prepared, and this is applied onto the above-mentioned base film and dried.

The dye layer formed in this way has a thickness of 0.2 to 5.0 am,
The thickness is preferably about 0.4 to 2.0 μm, and the sublimable dye in the dye layer accounts for 5 to 90% of the weight of the dye layer.
Suitably it is present in an amount of 10% to 70% by weight.

In another embodiment of the present invention, the dye layer may be formed without incorporating the stabilizer in the dye layer in the above embodiment, and the stabilizer may be formed as a thin film on the surface of the dye layer. A stabilizer layer can also be formed adjacent to the dye layer.

The thin film of the stabilizer may be formed by dissolving the above-mentioned stabilizer in a solvent, applying the solution to the surface of the dye layer or the surface of the base film, and drying it. is dissolved in a solvent together with the binder, applied to the surface of the dye layer or the surface of the base film, and dried to form a stabilizer layer.

The ratio of the stabilizer and binder used is not particularly limited, but numerically, the weight ratio is stabilizer/binder = 1/lO
It is about 10/1 to 10/1. Further, the thickness of the layer to be formed is generally about 0.05 to 10 LLm; if it is too thin, the stabilizing effect of the transferred dye will be insufficient, and if it is too thick, it will impede the transferability of the dye, which is not preferable.

The thermal transfer sheet of the present invention as described above may be provided with a heat-resistant layer on its back surface in order to prevent adverse effects caused by the heat of the thermal head.

The image-receiving sheet used to form an image using the thermal transfer sheet as described above may be of any type as long as its recording surface has dye-receptive properties for the above-mentioned dyes. In the case of paper, metal, glass, synthetic resin film or sheet, etc., which do not have a dye-receiving layer, a dye-receiving layer may be formed on at least one surface of a resin having excellent dye-receptivity. In addition, such a dye-receiving layer may contain solid waxes such as polyethylene wax, amide wax, and Teflon powder, which are known as release agents, fluorine-based or phosphate-based surfactants, silicone oil, etc. A preferred embodiment of the thermal transfer method of the present invention is as follows:
This is a method of using the thermal transfer sheet of the present invention, in which dye layers of different hues are transferred multiple times to form a color image by color synthesis, and simultaneously with the transfer of the last dye (separately, a stabilizer is added to the dye layer). (if a stabilizer layer is formed) or later (if a stabilizer layer is formed), the stabilizer is transferred to the dye transfer area (imaging area).

In another embodiment of the thermal transfer method of the present invention, when a color image is formed using a plurality of conventionally known single-color thermal transfer sheets, a stabilizer is incorporated in the dye layer of the thermal transfer sheet to be transferred last. May be used. Furthermore, after forming an image with a plurality of single-color thermal transfer sheets, a separate stabilizer thermal transfer sheet is created, and this is used to transfer the stabilizer in a transfer pattern similar to the dye transfer pattern after image formation. Good too. In a further preferred embodiment, a stabilizer layer is formed in parallel with the dye layer of the thermal transfer sheet, and the three colors or enclosures of, for example, yellow, magenta and cyan (and black) are applied face-sequentially onto the base sheet. In the case of provided color thermal transfer sheets, a stabilizer layer can be formed in addition to the dye layers and, after transfer of the dye, the stabilizer can be subsequently transferred to the imaged areas.

As the means for applying thermal energy during thermal transfer used in the method of the present invention, any conventionally known means can be used. Depending on the device,
5 to 100 by controlling the recording time.
mJ/mrr? By applying a certain amount of thermal energy, the intended purpose can be fully achieved.

(Effects) According to the present invention as described above, when a color image is formed by multiple thermal transfers, a dye stabilizer is included only in the dye layer used last, or the stabilizer is included on the surface of the dye layer. By forming a layer containing stabilizing agents and transferring these stabilizers to the image forming area simultaneously with or after the final dye transfer, color images with excellent light fastness and fade resistance can be obtained. .

According to the research conducted by the present inventors, compared to Ayosari in which a stabilizer is added to all dye layers, even if the amount of stabilizer added per layer is the same, it shows almost the same effect. In addition to being very economical since the total amount of stabilizer used is 1/2 to 1/4, there are other problems due to the use of a large amount of stabilizer, such as poor image tone. Problems such as dullness do not occur.

(Example) Next, the present invention will be described in more detail with reference to reference examples, examples, and comparative examples. In the text, parts or percentages are based on weight unless otherwise specified.

Reference Example 1 Synthetic paper (Yubo FRG-150, thickness 150 μm, manufactured by Tamago Yuka Co., Ltd.) was used as a base film, and a coating liquid with the following composition was applied to one side of the paper using a bar coater to give a coating of 5.0 g when dried.
Apply at a ratio of /d and immediately dry with a hair dryer.
Further, it was dried in an oven at 80° C. for 5 minutes to obtain a thermal transfer image-receiving sheet.

Polyester (Vylon 600, manufactured by Toyobo) 4.0 parts Vinyl chloride/vinyl acetate copolymer (#1OOOA, manufactured by Denki Kagaku Kogyo ■) 6.0 parts Amine-modified silicone (X-22-3050C1 manufactured by Shin-Etsu Chemical) 0
．． 2 parts Epoxy-modified silicone (X-22-3000E, manufactured by Shin-Etsu Chemical) 0.2 parts Methyl ethyl ketone/toluene (weight ratio 1/1) 89.6 parts Reference example 2 Ink composition for forming an enclosed dye layer having the following composition were prepared respectively.

Yellow (unsuitable stabilizer) Disperse dye (Macrolex Yellow 6G,
C, 1, Disperse Yellow 201, manufactured by Bayer) 5.5 parts polyvinyl butyral resin (S-LEC BX-), manufactured by Block Chemical Co., Ltd.)
4.5 parts Methyl ethyl ketone/toluene (weight ratio 1/1) 90.0 parts Magenta (stabilizing side not included) Disperse dye (Macrolex Red Violet)
R, CD1sperse Vjolet 26, manufactured by Bayer)■.

5.5 parts Polyvinyl butyral resin (S-LEC BX-1, manufactured by Sekisui Chemical Co., Ltd.) 4.5 parts Methyl ethyl ketone/toluene (weight ratio l/)) 90.0 parts 2 (stabilizing side not included) Disperse dye (Foron Br1lliant) blue
S-R, manufactured by Sandoz Co.)
3.0 parts polyvinyl butyral resin (S-LEC BX
-1゜Sekisui Chemical) 5.0 parts methyl ethyl ketone/toluene (weight ratio 1/1) 92.
0 parts black (stabilizing agent not included) Disperse dye (Macrolex Yellow 6G,
C, 1, Disperse Yellow 201, manufactured by Bayer AG) 2.5 part number dye (Macrole
x Red Vtolet R, C, I.

9 Disperse Violet 26, manufactured by Bayer AG) 2.5 part disperse dye (Foron Brilliant blue)
S-R, manufactured by Sandoz Co.)
2.0 parts polyvinyl butyral resin (S-LEC BX-
1゜Sekisui Chemical) 5.0 parts Methyl ethyl ketone/toluene (weight ratio 1/1) 88.0
Yellow (contains stabilizer) Disperse dye (Macrolex Yellow 6G,
C, 1, Disperse Yellow 201, manufactured by Bayer AG> 5.5 parts Ultraviolet absorber (Tinuv
in P, Ciba Geigy) 2.0 parts Polyvinyl butyral resin (S-LEC BX-1, Sekisui Chemical) 4.5 parts Methyl ethyl ketone/toluene (weight ratio 1/1) 88.0 parts Magenta (contains stabilizer) Dispersion Dye (Macrolex Red Violet
R, C, I.

DisperseViolet 26, manufactured by Bayer)
0 5.5 parts Ultraviolet absorber (Tinuvin P, manufactured by Ciba Geigy) 2.0 parts Polyvinyl butyral resin (S-LEC BX-1, manufactured by Sekisui Chemical) 4.5 parts Methyl ethyl ketone/toluene (weight ratio 1/1) 88.0 Foron Brilliant blue 12 (contains stabilizer) Disperse dye (Foron Brilliant blue
S-R, manufactured by Sandoz Co.)
3.0 parts Ultraviolet absorber (Tinuvin P, manufactured by Ciba Geigy) 2.0 parts Polyvinyl butyral resin (S-LEC BX-1 manufactured by Sekisui Chemical) 5.0 parts Methyl ethyl ketone/toluene (weight ratio 1/1) 90.0 parts Black (Contains stabilizer) Disperse dye (Macrolex Yellow 6G,
C, 1, Disperse Yellow 201, manufactured by Bayer AG) 2.5 part number dye (Macrole
x Red Violet R, C, I.

Disperse Violet 26, manufactured by Bayer AG) 2.5 partially disperse dye (Foron Brilliant blue)
e S-R, manufactured by Sandoz Co.)
2.0 parts Ultraviolet absorber (Tinuvin P, manufactured by Ciba Geigy) 2.0 parts Polyvinyl butyral resin (S-LEC BX-1 manufactured by Sekisui Chemical) 5.0 parts Methyl ethyl ketone/toluene (weight ratio 1/1) 86.0 parts Above 4 and 5μ ink with heat-resistant treatment on the back side
A dry coating amount of 1 m thick polyethylene terephthalate film (Lumirror 5AF53, manufactured by Toshi) was applied to each film.
．． Immediately after coating with a wire bar so as to give 0 g/rrf, it was briefly dried in a dryer, and further dried in an oven at 80° C. for 5 minutes to obtain 8 types of thermal transfer sheets.

Example 1 The above-mentioned thermal transfer sheet and thermal transfer image-receiving sheet were overlapped with their respective dye layers and dye-receiving surfaces facing each other, and the following was carried out using a thermal sublimation transfer printer (VY-100, newly manufactured by Hitachi Seisakusho). A color image was formed by recording with a thermal head from the back side of the thermal transfer sheet using a printing energy of 90 mJ/mrrf in the transfer order, and the results shown in Table 1 below were obtained.

a: Yellow-magenta → cyan → black 9b, yellow → magenta → cyan 0 C. Yellow-magenta 0 d: Yellow-cyan 8 e: Magenta-cyan 0 (*: contains stabilizer, no mark: does not contain stabilizer) ) Comparative Example 1 A color image was formed in the following printing order in the same manner as in Example 1, and evaluated in the same manner to obtain the results shown in Table 1 below.

a: yellow-magenta → cyan → black b yellow-magenta → cyan C: yellow-magenta d: yellow-cyan e: magenta-cyan 3 (* indicates that the stabilizing side is included, no mark indicates that the stabilizing side does not match) Comparative Example 2 Implementation Color images were formed in the same printing order as in Example 1, and evaluated in the same manner as in Example 1 to obtain the results shown in Table 1 below.

a: Yellow 8 → Magenta 0 → Cyan 0 → Black 0 b: Yellow 9 → Magenta 1 → Cyan 9 C: Yellow 0
→ Magenta 0 d: Yellow 9 → Cyan 9 e: Magenta 0 → Cyan 0 (* indicates that the stabilized side is included, no mark indicates that the stabilized side is not included) Comparative Example 3 A color image is formed in the same manner as Example 1 in the following printing order. The same evaluation was performed to obtain the results shown in Table 1 below.

a; Yellow 8 → Magenta 0 → Cyan 0 → Black b: Yellow 0 → Magenta - Cyan C: Yellow ○ - Magenta 0 4 d: Yellow 9 → Cyan e: Magenta 0 → Cyan (* indicates stabilization side included, unmarked indicates (no stabilizer) Example 2 Instead of the ultraviolet absorber in the four-color dye ink of Reference Example 2, the same amount of antioxidant (Sumilizer BBM-3
) was used to create four-color thermal transfer sheets, combined with the stabilizer-free thermal transfer sheet of Reference Example 2, color images were formed in the same manner as in Example 1 in the following order, and evaluated in the same manner. The results shown in Table 1 below were obtained.

a: Yellow → Magenta → Cyan → Black 0b: Yellow-magenta-cyan 0 C: Yellow-magenta 0 d: Yellow-cyan 9 e: Magenta-cyan medium (* indicates stabilization side included, no mark indicates stabilization side not included) Comparative Example 4 Dark fading properties of the same color images a to e as in Comparative Example 1.

The photofading rate of printing is the fading rate under JISJ grade irradiation conditions, and the dark fading rate is the rate of fading when the recorded image is dried at 70"C.
The fading rate after holding for 4 hours was compared. Each fading rate is a value calculated using the following formula.

0.D. = Reflection density of printed matter immediately after printing 0, D, =
Reflection density of printed matter after test 7 Example 3 In Reference Example 2, dye layers were formed on the same base film in the following order in the order shown below to obtain the thermal transfer sheet of the present invention, and the same as in Example 1 was obtained. When a color image was formed and similarly evaluated, the same results as in Example 1 were obtained.

a: Yellow-magenta → cyan → black.

b = yellow → magenta → cyan 9 C: yellow-cyan 9 d: magenta-cyan 0 (* indicates stabilizing side included, no mark indicates stabilizing side not included) Example 4 In Example 3-b, stable in the cyan dye layer Instead of adding a stabilizing agent, a cyan dye layer containing no stabilizer was formed, and the following composition was further applied on the surface of the cyan dye layer in a dry coating amount of 1. The thermal transfer sheet of the present invention was obtained by coating and drying at a ratio of Og/rd. When a color image was formed in the same manner as in Example 1 and evaluated in the same manner, similar results were obtained. Tinuvin P) 4.0 parts Methyl ethyl ketone/toluene (weight ratio 1/1190.0 parts Example 5 In Example 3-b, instead of adding a stabilizer to the cyan dye layer, a cyan dye containing no stabilizer was used. A layer was formed, and the same stabilizing adjuvant composition as in Example 4 was applied in the same manner as in Example 4 at a dry coating amount of t, og/rrf and dried to form a stabilizer layer. A thermal transfer sheet of the present invention was obtained.After image formation in the same manner as in Example 1, a stabilizer was transferred thereon and evaluated in the same manner, and the same results were obtained.

Example 6 Instead of the ultraviolet absorber or antioxidant in Example 1 or 2, Sumilizer BHT, Sumili
zerGM, Sumilizer MB, 5ulT
lilizer TPP-R, Yoshinox 425, Yoshinox SR, Irganox-1081, Irga
nox-1222, Mark AO-40, Tinuv
in 234, Tinuvin320, Tinuvin
326, Tinuvin 327, Tinuvin
327, Sumisorb 110, Sun+1sor
b140, Kemisorb 10, Kemi-sor
b11. Kemisorb 12, Kemisor
b 13 , Uvinulx-19, Uvinul
Ms-40, Tomisorb 100, Tomisorb 600,
Viosorb-80, Viosorb-90, Sanol LS-770, Sanol LS-765, Sanol LS
-774, Sumisorb TM-061, etc., an ultraviolet absorber, and a light stabilizer were used, but in the same manner as in Example 1 or 2, an image with excellent light fastness and fade resistance was obtained.

Claims (3)

[Claims] (1) In a thermal transfer sheet in which dye layers of multiple colors are formed on the surface of a base film, it is confirmed that a dye stabilizer is contained in or on the surface of the last dye layer to be transferred. Features thermal transfer sheet. (2) The thermal transfer sheet according to claim 1, wherein the stabilizer is an antioxidant, an ultraviolet absorber, or a light stabilizer with a molecular weight of less than 500. (3) The dye layer of the thermal transfer sheet with the dye layer formed on the surface of the base film and the receiving layer of the image receiving sheet with the dye receiving layer on the surface of the base film are stacked facing each other, and from the back side of the thermal transfer sheet, A thermal transfer method in which a color image is formed by image-wise heating and transfer multiple times, characterized in that a dye stabilizer is transferred to an image forming area simultaneously with or after the last transfer.