JPH11180058A - Thermal transfer recording sheet - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a heat resistive sliding layer having high heat resistance and a head cleaning property simultaneously by being formed on a cured substance mainly obtained from a curable resin in its heat resistive sliding layer and a heat softening resin incompatible with this. SOLUTION: A heat softening resin added to a curable resin is incompatible, so that high local density areas of heat softening resin tend to exist independently each other and form a sea-island structure. An insular noncontinuous area is phase isolation being in the range that can be observed by the use of an optical microscope. The configuration of the insular area of heat softening resin is circle. Also, the maximum diameter is preferable to be 0.1-20 μm, and further, 0.05-20 μm in terms of a head cleaning property. Furthermore, a mixing weight ratio between curable resin and heat softening resin being incompatible with this is preferably used in the range of 98/2-70/30 (curable resin/heat softening resin).

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a thermal transfer recording sheet, and more particularly, to a thermal transfer recording sheet which can be advantageously used for color recording in an OA terminal such as a printer, a facsimile, a copying machine or the like, or for color recording of a television image.

[0002]

2. Description of the Related Art Various methods, such as electrophotography, ink jet, and thermal transfer recording, have been studied for color recording. However, thermal transfer recording methods have other problems in terms of maintainability and operability of the apparatus. This is advantageous as compared with the above method. In the thermal transfer recording method, generally, an image receiving body made of a colorant receptive resin is superimposed on a colorant layer of a thermal transfer recording sheet in which an ink in which a colorant is dispersed in a binder resin is applied on a plastic base material such as polyester. At the same time, recording is performed by heating the back surface of the thermal transfer recording sheet with a thermal head and transferring the color material of the thermal transfer recording sheet to the image receiving body. Such methods include a fusion type thermal transfer recording method using a heat-meltable ink and a sublimation type thermal transfer recording method using an ink containing a sublimable (or heat transferable) dye.

In recent years, the thermal energy density applied to a thermal transfer recording sheet has tended to increase in order to improve the image forming speed and the color density. In such a technical environment, the purpose is to prevent fusion between the thermal transfer recording sheet and the thermal head during image formation, and to reduce wrinkles generated in the thermal transfer recording sheet during image formation at high energy density. Thus, a lubricating layer made of a resin having higher heat resistance has been formed on the surface of the base material in contact with the thermal head.

[0004]

As such a high heat-resistant resin, a thermoplastic resin having a high glass transition temperature (Tg) or a resin based on photo-curing or thermo-curing is used to improve heat resistance. Something has been devised. However, in general, T
A high-g thermoplastic resin has poor adhesion to polyethylene terephthalate (PET) film, which is widely used as a substrate, and if a low-Tg thermoplastic resin is mixed as a primer to improve this, sufficient heat resistance can be obtained. Does not improve.

On the other hand, a curable resin system has good adhesion to PET, but has poor ability to remove fine dust adhering to a thermal head (head cleaning property).
This ability is provided by adding fine particles to the heat-resistant lubricating layer. However, in general, when a large amount of fine particles are added to the heat-resistant lubricating layer, the coefficient of friction with the thermal head is increased, and the lubrication is reduced.

When a thermoplastic resin having an appropriate range of Tg is used for the heat-resistant lubricating layer, the resin is softened by the heat applied from the thermal head at the time of image formation, and the adhesiveness at this time causes the head cleaning property. Is expressed. In this case, if the heat transfer recording sheet is wound and stored at a high temperature, interlayer adhesion occurs between the coloring material layer and the heat-resistant lubricating layer, or the lubricant contained in the heat-resistant lubricating layer is transferred to the coloring material layer. There is a problem of shifting. An object of the present invention is to solve the above-mentioned problems of the prior art, that is, to obtain a heat-resistant lubricating layer having high heat resistance and at the same time having head cleaning properties.

[0007]

As a result of intensive studies, the inventor of the present invention has found that the heat-resistant lubricating layer constituting the back layer of the thermal transfer recording sheet is mainly composed of a cured product of the curable resin and an incompatible with the curable resin. In particular, when the heat-softening resin is composed of a continuous region formed of a curable resin portion and a non-continuous region in which the heat-softening resin portion is formed in an island shape independently of each other, In some cases, it has been found that the above-mentioned object can be achieved, and the present invention has been completed. That is, the present invention provides a heat transfer recording sheet in which a heat-resistant lubricating layer is provided on one surface of a base film and a coloring material layer is provided on the other surface, wherein the heat-resistant lubricating layer is mainly obtained from a curable resin. An object of the present invention is to provide a thermal transfer recording sheet made of a cured product and an incompatible thermosoftening resin.

[0008] The curable resin in the present invention is a resin capable of forming a three-dimensional infinite network structure by causing a cross-linking reaction by physical or chemical stimulus. Indicates a resin or a reactive monomer (oligomer). As the curable resin, a resin having two or more active hydrogens such as a hydroxyl group and an amino group in one molecule is preferable, and these are used after being cured with a polyisocyanate having two or more functionalities. Specific examples of the active hydrogen-containing resin, polyvinyl formal, polyvinyl acetal, polyvinyl butyral, ketalized polyvinyl alcohol such as polyvinyl acetoacetal,
Modified cellulose, acrylic polyol, polyester polyol, polyether polyol, polyacrylamide and the like can be mentioned. The polyisocyanate used for curing may be any known diisocyanate or a polyisocyanate such as triisocyanate used in the synthesis of a known adhesive or polyurethane, for example, paraphenylene diisocyanate, 2,4-toluene diisocyanate, 2,2 6-toluene diisocyanate, hexamethylene diisocyanate, 4,4′-biphenylene diisocyanate, triphenylmethane triisocyanate, 4,4 ′, 4 ″ -trimethyl 3,3 ′, 2′-triisocyanate-triphenyl cyanurate and the like, Examples include a compound of propylene glycol and tolylene diisocyanate, and a compound of trimethylolpropane and toluene diisocyanate.

Other curable resins include a curing reaction of a mixture of a monofunctional acrylate and a polyfunctional acrylate with a photoradical generator, and a curing of a polymer having an unsaturated bond in a side chain with a polyfunctional acrylate. A resin that can be cured by various known crosslinking reactions including a reaction and a curing reaction of an epoxy resin by a photocation generator can be used. The thermosoftening resin used in the present invention is not particularly limited as long as it shows incompatibility with the curable resin in the state of a coating liquid. Examples of the thermosetting resin include a linear polymer compound, a graft polymer compound, a star-shaped polymer compound, and the like, and the molecular weight is usually 1,000 to 100,000, more preferably 5,000.
範 囲 30,000. The glass transition temperature (Tg) of the thermosetting resin is preferably in the range of 20 to 100 ° C, more preferably 40 to 70 ° C. More specifically, polyethylene terephthalate (PE) as a base film
Polyesters similar in chemical structure to T) are preferably used. By using such a polymer compound, the adhesiveness to the PET film of the base material can be further improved.

In the heat-resistant lubricating layer of the present invention, these curable resin portions form continuous regions, and the thermally softening resin portions independently form island-shaped discontinuous regions independently of each other. Develop head cleaning properties. That is, when a curable resin and another resin are mixed as in the related art, if the compatibility is good, the cured product forms an interpenetrating polymer network, and the head cleaning property is not effectively exhibited. In other words, since the heat-softening resin added to the curable resin is incompatible, the regions where the local concentration of the heat-softening resin is high exist independently of each other and the probability of forming a sea-island structure increases. The island-shaped area of this structure selectively generates tackiness during image formation, removes fine dust adhering to the thermal head, and provides good head cleaning properties. For this reason, both resins are required to be incompatible. Here, the island-shaped discontinuous region is a phase separation in a range observed using an optical microscope. The shape of the island region of the thermosoftening resin of the present invention is circular, and the maximum diameter when observed from above is 0.1 to 20 μm.
It is preferably from 0.5 to 20 μm from the viewpoint of head cleaning properties. The mixing weight ratio of the curable resin to the heat-softening resin incompatible with the curable resin is 98/2 to 70/30.
The range of (curable resin / thermosoftening resin) is preferably used.

The lubricant used in the heat-resistant lubricating layer of the present invention includes acid-type phosphates, salt-type phosphates and phosphites, (modified) silicones, fluorine-based surfactants, higher fatty acid esters, metal soaps Etc. can be used as appropriate. Further, for the purpose of reducing the transfer of the lubricant to the colorant layer, silica, mica, talc, calcium carbonate,
Amorphous inorganic particles such as titanium oxide, and spherical or amorphous fine particles such as fluororesin, silicone resin, benzoguanamine, polyethylene, and polypropylene can be used. At this time, the average particle diameter of the fine particles is 0.5 μm or more.
3 μm is preferred. Furthermore, in order to make the coefficient of friction of the heat-resistant lubricating layer appropriate and to improve the head cleaning property, the above-mentioned amorphous inorganic fine particles can be used in combination. In this case, the average particle diameter is 0.01 to 0.2 μm. It is.

The coating amount of the heat-resistant lubricating layer is generally preferably from 0.1 to 2 μm, more preferably from 0.5 to 2 μm in dry film thickness.
2 μm. Above all, it is preferable that the coating amount when the particles are added is 50 to 90% of the average particle diameter of the larger particles. A heat-resistant lubricating layer obtained by curing an active hydrogen-containing resin with a curing agent cannot be sufficiently crosslinked by heat at the time of application and drying alone, and is generally aged for several hours to several days at a temperature of 40 ° C. or more. To improve the film strength.

As the base film in the present invention,
Although there is no particular limitation, it is preferable to use a biaxially stretched polyethylene terephthalate film, but it is also effective to use a film having excellent heat resistance such as a polyethylene naphthalate film or an aromatic polyamide film. For the base film, a corona discharge treatment is applied to improve the adhesiveness with the heat-resistant lubricating layer and the coloring material layer, and a polyester-based resin, a cellulose-based resin, a polyvinyl alcohol-based resin, a urethane resin, and a polyvinylidene chloride-based resin are used. For example, an undercoating process may be performed.

The thickness of the base film is not particularly limited, but is preferably 2 to 10 μm. The method for forming the coloring material layer provided on the surface opposite to the heat-resistant lubricating layer on the base film of the thermal transfer recording sheet is not particularly limited.For example, in the case of a sublimation type thermal transfer recording sheet, Sublimation or heat diffusible dye and heat resistant binder resin,
Dissolve or disperse in an appropriate solvent to prepare an ink,
This ink can be applied to a base film and dried to form a coating.In the case of a fusion-type thermal transfer recording sheet, a coloring material such as a pigment or a pigment is added to a heat-fusible substance, if necessary, with a solvent. Ink can be prepared by dissolving or dispersing the ink to prepare an ink, and applying the ink to a base film and drying.

The sublimation or heat diffusing dyes used in the sublimation type thermal transfer recording sheet include azo, anthraquinone, styryl, naphthoquinone, quinophthalone, and the like.
Various nonionic dyes such as azomethine, coumarin, and condensed polycyclic are used, and as a binder resin, polycarbonate resin, polysulfone resin,
Cellulose resins such as polyvinyl butyral resin, phenoxy resin, polyarylate resin, polyamide resin, polyaramid resin, polyimide resin, polyetherimide resin, polyester resin, acrylonitrile-styrene resin and acetylcellulose, methylcellulose, and ethylcellulose are used. . As the solvent, aromatic solvents such as toluene and xylene; ketone solvents such as methyl ethyl ketone, methyl isobutyl ketone and cyclohexanone; ester solvents such as ethyl acetate and butyl acetate; alcohol solvents such as isopropanol, butanol and methyl cellosolve; Ether solvents such as dioxane and tetrahydrofuran; amide solvents such as dimethylformamide and N-methylpyrrolidone are used.

As the coloring material used for the fusion type thermal transfer recording, for example, inorganic pigments such as carbon black; various organic pigments such as azo type and condensed polycyclic type are used as pigments; And basic dyes, oil-soluble dyes, metal complex dyes and the like. As the heat-fusible substance, a solid or semi-solid substance having a melting point of 40 to 120 ° C. is preferable, and examples thereof include paraffin wax, microcrystalline wax, carnauba wax, montan wax, wood wax, and oil-based synthetic wax. As the solvent, those similar to the case of the above-described sublimation type thermal transfer recording sheet can be used.

In the color material layer ink, in addition to the above components, organic or inorganic non-sublimable particles, a dispersant, an antistatic agent, an antiblocking agent, an antifoaming agent, an antioxidant, if necessary. Additives such as agents, viscosity adjusters, pH adjusters, and lubricants may be added. These color material layer inks may be applied by the same application method as that of the heat-resistant lubricating layer, and the coating film thickness is suitably 0.1 to 5 μm in terms of dry film thickness.

[0018]

EXAMPLES The present invention will be described in more detail with reference to the following Examples, which should not be construed as limiting the scope of the present invention unless it exceeds the gist thereof.

Example 1 (a) Preparation of thermal transfer recording sheet ESREC KS-1 (polyvinyl acetal resin, molecular weight of about 30,000, acetalization degree of 70 mol% or more,
Acetyl group 3 mol% or less, manufactured by Sekisui Chemical Co., Ltd.)
40 parts by weight, Byron 200 (saturated polyester resin,
(Molecular weight 15,000-20,000, Tg67 ° C., manufactured by Toyobo Co., Ltd.) 10 parts by weight, and Fospair-41
(Acid type phosphate ester amine salt, manufactured by Sakai Chemical Industry Co., Ltd.)
50 parts by weight were stirred and dissolved in 710 parts by weight of a mixed solvent of toluene, 2-butanone and (1: 1). On the other hand, Mytec GP105A (polyisocyanate,
80 parts by weight of a solid content of 75% (manufactured by Mitsubishi Chemical Corporation) were mixed to obtain a heat-resistant lubricating layer coating solution. In each of the solutions before and after the addition of the curing agent, phase separation of the resin was confirmed. In addition, the observation evaluation of the phase separation of the resin in a liquid was performed visually by the turbidity of the solution.

This liquid is applied to a biaxially stretched polyethylene terephthalate film having a thickness of 4.5 μm so that the wet film thickness becomes about 6 μm, dried at 130 ° C. for 5 seconds, and dried at 1.1 μm.
A thick heat-resistant lubricating layer was formed, and the obtained heat-resistant lubricating layer was magnified 500 times with an optical microscope and observed. As a result, an island region was confirmed, and the maximum diameter was 7 μm. Then 60 ° C
The film was aged for 3 days, and 4 parts by weight of a red sublimable dye (Color Index, Disperse Red 60), 10 parts by weight of phenoxy resin, 90 parts by weight of methyl ethyl ketone, 10 parts by weight of isopropanol 10 Apply and dry ink consisting of parts by weight,
A color material layer having a thickness of 1.0 μm was formed to prepare a thermal transfer recording sheet.

(B) Preparation of Image Receiver 10 parts by weight of TR-220 (saturated polyester resin, manufactured by Nippon Synthetic Chemical Industry Co., Ltd.), 0.5 parts by weight of KF393 (amino-modified silicone oil, manufactured by Shin-Etsu Chemical Co., Ltd.) A liquid consisting of 15 parts by weight of methyl ethyl ketone and 15 parts by weight of toluene is applied to a synthetic paper (trade name: YUPO FPG150, manufactured by Oji Oil Chemical Synthetic Paper Co., Ltd.) using a wire bar, dried (5.1 μm in dry film thickness), and further oven 90 ° C in
Was dried by heating for 20 minutes to prepare an image receiving body.

(C) Evaluation (Thermal transfer recording test) The color material layer surface of the thermal transfer recording sheet produced as in (a) above and the resin-coated surface of the image receiving body produced by the above method (b) are overlapped. (Thermal transfer recording test piece). A partial grace type line thermal head having a heating resistor density of 6 dots / mm is pressed against the heat-resistant lubricating layer side of the recording sheet with a force of 2 kgf against this, and the pressure is 0.4 kg / mm.
Thermal transfer recording was performed by continuously applying a power of W / dot at a cycle of 11 ms for 10 ms. Table 1 shows the results regarding the presence or absence of image defects (smiles) due to the elongation of the color sheet.

(Test of Head Cleaning Property) When performing transfer recording in the same manner as in the above-described thermal transfer recording test, an artificial 1 mm-diameter 2 mm long piece was placed on the side of the heat-resistant lubricating layer of the first thermal transfer recording test piece. After spraying a small amount of dust and performing thermal transfer recording, thermal transfer recording was performed on the second and subsequent thermal transfer recording test pieces under the same conditions without spraying artificial dust. The head cleaning property was evaluated based on the presence or absence of streaks of reduced color density due to artificial dust on the second and subsequent test pieces. The results are shown in Table 1. Here, the sample having no streak on the second and third test pieces has the head cleaning property "Yes", and the sample having the streak on the second sheet and no streak on the third test piece. When the cleaning property was “low”, the streaks occurred in the second and third sheets, and the cleaning property was “none”.

(Storability Evaluation Test) The thermal transfer recording sheet prepared as in the above (a) was wound around a plastic tube having an outer diameter of 1 cm and stored for 3 days in an environment at a temperature of 50 ° C. and a relative humidity of 90%. Next, the presence or absence of an image defect and the presence or absence of interlayer fusion between the color material layer and the heat-resistant lubricating layer were evaluated under the same conditions as in the thermal transfer recording test. The results are shown in Table 1.

Example 2 A heat-resistant lubricating layer was produced in the same manner as in Example 1 except that the following talc particles were added to the above-mentioned heat-resistant lubricating layer. That is, 10 parts by weight of LMS # 200 (talc, average particle size 1.5 μm, manufactured by Fuji Talc Corporation) was added to the solution before the addition of the curing agent Mitec GP105A described in (a) of Example 1. For 1 hour with a paint shaker. 80 parts by weight of Mitec GP105A as a curing agent was mixed with this dispersion to obtain a coating liquid for a heat-resistant lubricating layer. Next, Example 1
A heat-resistant lubricating layer (with a dry film thickness of 1.1 μm)
m) and a color material layer were formed and evaluated in the same manner as in Example 1. Although phase separation of the resin was confirmed in the above-mentioned coating solution for a heat-resistant lubricating layer, an island-shaped region having a size that could be confirmed by an optical microscope could not be observed in the prepared heat-resistant lubricating layer.

Example 3 A heat transfer recording sheet was prepared and evaluated in the same manner as in Example 1 except that the heat-resistant lubricating layer was not aged in the heat transfer recording sheet prepared in Example 1.

Example 4 A heat-resistant lubricating layer was prepared in the same manner as in Example 1 except that the following modified silicone oil was used as a lubricant. That is, instead of dissolving Fospre-41 with the solution before adding the curing agent Mitec GP105A described in (a) of Example 1, KF was used.
-865 (amino-modified silicone oil, amine equivalent 4,400 g / mol, viscosity 90 cSt (25 ° C.), manufactured by Shin-Etsu Chemical Co., Ltd.) 10 parts by weight, and thereafter, the same as (a) of Example 1 A heat-resistant lubricating layer (dry film thickness: 1.1 μm) and a coloring material layer were formed by the method, and evaluation was performed in the same manner as in Example 1. Although phase separation of the resin was confirmed in the above solution, no island-like region having a size that could be confirmed by an optical microscope was observed in the heat-resistant lubricating layer thus formed.

Example 5 Example 1 was repeated except that polyvinyl butyral was used instead of polyvinyl acetal as the active hydrogen-containing resin.
A heat-resistant lubricating layer was prepared in the same manner as described above. That is, instead of dissolving Eslek KS-1 with the solution before mixing the curing agent Mitec GP105A described in (a) of Example 1, Eslek BX-1 (polyvinyl butyral resin, about 33 mol% of hydroxyl groups, acetylation degree 3 mol% or less, manufactured by Sekisui Chemical Co., Ltd.) 40 parts by weight are dissolved, and thereafter, the heat-resistant lubricating layer (dry film thickness: 1.1 μm) and the coloring material layer are formed in the same manner as in Example 1 (a). Was formed to obtain a thermal transfer recording sheet for evaluation, and evaluation was performed in the same manner as in Example 1.

Comparative Example 1 A heat-resistant lubricating layer was prepared in the same manner as in Example 1 except that no heat-softening resin was contained. That is, 40 parts by weight of Eslek KS-1 and 50 parts by weight of Fospar-4 were stirred and dissolved in 665 parts by weight of a mixed solvent of toluene, 2-butanone and (1: 1). Thereafter, a heat-resistant lubricating layer (dry film thickness: 1.1 μm) and a coloring material layer are formed by the same method as in (a) of Example 1 to obtain a thermal transfer recording sheet for evaluation. Was evaluated.

Comparative Example 2 A heat-resistant lubricating layer was prepared by adding two kinds of particles to the heat-resistant lubricating layer of Comparative Example 1. That is, the curing agent Mitec G of Comparative Example 1
Before adding P105A, add Trefil R-93 to the solution.
0 (spherical silicone resin particles, average particle size 1.0 μm, manufactured by Dow Corning Toray Silicone Co., Ltd.) and 10 parts by weight of Aerosil R-972 (fine silica particles, average particle size 16 nm, manufactured by Nippon Aerosil Co., Ltd.) And dispersed by a paint shaker for 2 hours.
For this dispersion, the curing agent Mytec GP105A
Was mixed to obtain a heat-resistant lubricating layer coating solution. Thereafter, a heat-resistant lubricating layer and a coloring material layer were formed in the same manner as in Example 1 (a), a thermal transfer recording sheet for evaluation was obtained, and evaluation was performed in the same manner as in Example 1.

COMPARATIVE EXAMPLE 3 A heat-resistant lubricating layer was prepared without adding the isocyanate and hardening the thermosetting resin. 80 parts by weight of ESREC KS-1, 20 parts by weight of Byron 200, and Fospare-
41 of 12 parts by weight of toluene and 2-butanone (1: 1:
It was dissolved by stirring in 510 parts by weight of the mixed solvent of 1). This solution was applied to a biaxially oriented polyethylene terephthalate film having a thickness of 4.5 μm so that the wet film thickness was about 6 μm.
After drying at 30 ° C. for 5 seconds, a heat-resistant lubricating layer having a thickness of 1.1 μm was formed. No aging was performed on this back layer. On the opposite side of the heat-resistant lubricating layer of this film, 4 parts by weight of a red-based sublimable dye (Color Index, Disperse Red 60), 10 parts by weight of phenoxy resin, 9 parts of methyl ethyl ketone
An ink composed of 0 parts by weight and 10 parts by weight of isopropanol was applied and dried to form a color material layer having a thickness of 1.0 μm, and a thermal transfer recording sheet for evaluation was obtained. The evaluation was performed in the same manner as in Example-1.

Example 6 A heat-resistant lubricating layer was prepared in the same manner as in Example 1 except that a thermosetting resin having a higher Tg was contained as an incompatible resin. That is, Eslek KS-1 (polyvinyl acetal resin,
Molecular weight of about 30,000, degree of acetalization of 70 mol% or more, acetyl group of 3 mol% or less, 40 parts by weight of Sekisui Chemical Co., Ltd., Vylon 290 (saturated polyester resin, molecular weight of 20,000 to 25,000, Tg of 77 ° C.)
10 parts by weight of Toyobo Co., Ltd.
50 (acid type phosphoric acid ester amine salt, manufactured by Sakai Chemical Industry Co., Ltd.) 50 parts by weight with toluene and 2-butanone (1: 1)
Was stirred and dissolved in 710 parts by weight of a mixed solvent. On the other hand, 80 parts by weight of Mytec GP105A (polyisocyanate, solid content: 75%, manufactured by Mitsubishi Chemical Corporation) as a curing agent was mixed to obtain a coating liquid for a heat-resistant lubricating layer. Further, a heat-resistant lubricating layer and a coloring material layer were formed by the same method as in (a) of Example 1 to obtain a thermal transfer recording sheet for evaluation, and evaluation was performed in the same manner as in Example 1.

[0033]

[Table 1] Table 1 Evaluation results ──────────────────────────────────── Sea island Island area image Defects Head chestnut structure after storage Maximum diameter Before storage After storage Abrasiveness Interlayer fusion 着例 Example 1 Yes 7μm No No Yes Yes No Example 2 No-No No Yes No No Example 3 Yes 6μm No No Yes Somewhat Example 4 No-No No No Yes No Example 5 Yes 12μm No No No No Example 6 Yes 20 μm No No Low No No Comparative Example 1 No No No No No No Comparative Example 2 No No No No No No Comparative Example 3 Yes 7 μm No Evaluation not possible Yes Generated ───────────── ───────────────────────

Summary of Results As can be seen from Comparative Examples 1 and 2, a heat-resistant lubricating layer containing no Byron 200, which is a heat-softening resin incompatible with a curable resin, does not exhibit cleaning properties. Comparative Example 3
As can be seen from the above, when the requirement for curing the resin is not satisfied without adding the curing agent, interlayer fusion occurs between the coloring material layer and the heat-resistant lubricating layer when stored under high-temperature and high-humidity conditions. From the above, it can be seen that a mixed resin system of a thermosetting resin and a thermosoftening resin is essential for simultaneously satisfying the head cleaning property and the preservability.

The heat transferable recording sheet having a heat-resistant lubricating layer according to the present invention hardly causes image defects, has a head cleaning property, and does not cause interlayer fusion even when stored under high temperature and high humidity conditions. is there.

Claims (4)

[Claims] 1. A heat transfer recording sheet in which a heat-resistant lubricating layer is provided on one surface of a base film and a color material layer is provided on the other surface, wherein the heat-resistant lubricating layer mainly comprises a cured product of a curable resin. A thermal transfer recording sheet, wherein the curable resin comprises an incompatible thermosoftening resin. 2. A curable resin portion forms a continuous region, and a thermo-softening resin portion forms an island-shaped discontinuous region independently of each other. The maximum diameter of the island-shaped region is 0.05 to 20 μm. 2. The thermal transfer recording sheet according to claim 1, wherein: 3. The thermosoftening resin has a glass transition temperature of 40 to 7
The thermal transfer recording sheet according to claim 1, wherein the temperature is 0 ° C. 4. 4. The thermal transfer recording sheet according to claim 1, wherein the cured product is cured with a polyisocyanate using a curable resin comprising an active hydrogen-containing resin.