JPH04131285A - Image receiving sheet for thermal transfer recording - Google Patents

Abstract

PURPOSE:To obtain a high density image without using high heat energy at the time of thermal transfer and to ensure the good heat-resistant preservability of an image after thermal transfer by adding a specific binder resin and a specific resin to an image receiving layer. CONSTITUTION:An image receiving sheet is usually constituted of a base material and the image receiving layer 2 formed thereon. The image receiving layer 2 contains a specific binder resin and a specific resin and, as the specific binder resin, an alpha-olefin resin, oxide of an alpha-olefin resin, chloride of an alpha-olefin resin, paraffin wax, oxide of paraffin wax and chloride of paraffin wax are used. As the specific resin, a vinyl chloride resin, polyester and polycarbonate can be designated. By this constitution, a high density image can be obtained without using high heat energy at the time of thermal transfer and the good heat resistance of an image can be obtained after thermal transfer and, therefore, a sharp image of high quality can be preserved over a long period of time.

Description

Detailed Description of the Invention [Field of Industrial Application] The present invention relates to an image-receiving sheet for thermal transfer recording, and more specifically, the present invention relates to an image-receiving sheet for thermal transfer recording. This invention relates to an excellent image-receiving sheet for thermal transfer recording.

[Prior Art and Problems to be Solved by the Invention] Conventionally, color recording techniques such as inkjet, electrophotography, and thermal transfer have been studied as methods for obtaining color hard copies.

Among these, the thermal transfer method in particular has advantages such as easy operation and maintenance, miniaturization of the device, and low cost.

There are two types of this thermal transfer method:

That is, a method in which a transfer sheet having a meltable ink layer on a support is heated imagewise (imagewise) by a laser or a thermal head, and the meltable ink layer is melt-transferred onto an image-receiving sheet for thermal transfer recording. Using a heat-sensitive transfer recording ink sheet having an ink layer containing a heat-diffusible dye (sublimable dye) on a support, J! ! There are two types: - a thermal diffusion transfer method in which the thermally diffusible dye is diffusely transferred to an image-receiving sheet for thermal transfer recording;

Among these, the thermal diffusion transfer method can control the gradation of the image by changing the amount of dye transferred according to changes in the thermal energy of the thermal head.
By overlapping magenta and yellow recording,
As a method for obtaining color images with continuous changes in color shading.

It has been attracting attention in recent years.

However, this thermal diffusion transfer method has a problem with the image receiving sheet for thermal transfer recording used.

That is, the problem with R- is that it is difficult to obtain a high-density image unless high thermal energy is applied during thermal transfer.

Furthermore, applying high thermal energy slows down the printing speed and shortens the life of the thermal head.

The second problem is that one image does not have sufficient heat-resistant storage stability.

In other words, if an image-receiving sheet for thermal transfer recording is placed in a high-temperature environment, the image will increase or discolor over a long period of time.
Image clarity decreases.

The present invention has been made to solve the various problems mentioned above.

That is, an object of the present invention is to provide a thermal transfer method that can obtain high-density images without using high thermal energy during thermal transfer, and that can exhibit good heat-resistant storage stability of images after thermal transfer. An object of the present invention is to provide an image-receiving sheet for recording.

[Means for solving the above-mentioned problems] The present invention for achieving the above-mentioned objects is characterized by having an image-receiving layer containing a binder resin selected from the following group A and a resin selected from the following group B. This is an image receiving sheet for thermal transfer recording.

Group A: α-olefin resin, oxide of α-olefin resin, chlorinated product of α-olefin resin, paraffin wax, oxide of paraffin wax, chlorinated product of paraffin wax.

Group 8: Vinyl chloride resin, Bossester, polycarbonate.

The present invention will be explained in detail below.

[I] Image-receiving sheet for thermal transfer recording The image-receiving sheet for thermal transfer recording of the present invention, as shown in FIG. 1(A), usually comprises a base material 1 and an image-receiving layer 2 formed thereon. I can do it.

Further, the image receiving sheet for thermal transfer recording of the present invention is shown in FIG.
As shown in (b), depending on the case, the image receiving layer 2a may be formed with only the self-supporting image receiving layer 2a.

In the image-receiving sheet for thermal transfer recording comprising this self-supporting image-receiving layer 2a, since no base material is used, the number of parts and manufacturing steps can be reduced.

Image-Receiving Layer In the present invention, the image-receiving layer contains a specific binder resin and a specific resin (which can also be considered as a type of binder resin).

■Binder resin In the present invention, binder resins include α-olefin resins, oxides of α-olefin resins, chlorinated products of α-olefin resins, paraffin wax, oxides of paraffin wax, and chlorine of paraffin wax represented by the following general formulas. Use chemical substances.

Y -C-C-・ ・ ・ ・ ・ ・ ・ ・ [1
])(X (In the general formula [I], X is -H1-COoRl-
COOHl-0COR1-OR or -CONHR, Y is -H or -CHj, and R has 1 to 4 carbon atoms
Typical specific examples of the above binder resin (representing an alkyl group of Examples include (meth)acrylic acid amide, and oxides or chlorinated products thereof (excluding vinyl chloride resin).

These binder resins can be used alone or in combination of two or more.

The binder resin is preferably solid at room temperature (25°C).

The molecular weight of the binder resin is not particularly limited or is usually 200 to +000,000, preferably 5
00 to ZO0,000.

Furthermore, from the perspective of thermal behavior, the ring and ball softening point is 3.
A binder resin having a temperature of 0 to 150°C is preferred.

■Specific Resin In the present invention, it is important that the image-receiving layer contains the following specific resins.

That is, specific resins referred to in the present invention include vinyl chloride resins, polyesters, and polycarbonates.

These can be used alone or in combination of two or more.

Among the above-mentioned king resins, vinyl chloride resins are particularly preferred.

The vinyl chloride resin used in the present invention may be polyvinyl chloride, which is a homopolymer of vinyl chloride, or may be a copolymer of vinyl chloride and other polymers.

In the latter case, it is desirable to contain 50 mol% or more of vinyl chloride.

Examples of the units having the above values constituting the copolymer include vinyl acetate and vinyl propionate.

Alkylnisdales of unsaturated fatty acids such as vinyl tallow; acrylic acid, methacrylic acid, methyl acrylate, ethyl methacrylate, butyl acrylate, 2-hydroxyethyl methacrylate, 2-ethylhexyl acrylate, etc. acrylic acid or methacrylic acid and its alkyl esters; maleic acid and its alkyl esters such as maleic acid, dibutyl maleate, diethyl maleate, dioctyl maleate; methyl vinyl ether, 2-ethylhexyl vinyl ether, lauryl vinyl ether, valmityl Alkyl vinyl ethers such as vinyl ether and stearyl vinyl ether; vinylidene chloride; ethylene; propylene: acrylonitrile; methaxonitrile; styrene; chlorostyrene; itaconic acid and its alkyl esters; crotonic acid and its alkyl esters, dichloroethylene, trifluoroethylene Examples include halogenated olefins such as cycloolefins such as cyclopentene, aconitic acid esters: vinyl benzoate; benzoyl vinyl ether.

Regarding the degree of polymerization of vinyl chloride resin, JIS K
6721 in the range of 275 to 2,460, but in the present invention, vinyl chloride resins can be used regardless of this.

Next, the polyester (excluding polycarbonate) used in the present invention refers to a polymer having a plurality of ester bonds within one molecule.

Such polymers can usually be synthesized by polymerization of diols and dibasic acids or by ring-opening polymerization of lactones.

Commercially available Bossesters include, for example, Byron 200, Byron 290. Byron 600 [manufactured by Toyobo M Co., Ltd.], KA-1038C [Arayo Chemical Co., Ltd.]
[manufactured by Nippon Gosei Co., Ltd.], TP220, and 235 [all manufactured by Nippon Gosei Co., Ltd.].

Next, what is the polycarbonate used in the present invention?

A polyester of carbonic acid and glycol or dihydric phenol.

Preferred examples of the glycol or dihydric phenol include p-xylylene glycol, 2,2-bis(4-oxyphenyl)propane, bis(4-oxydiphenyl)methane, 1,1-bis(4-oxy) phenylethane), 1.1-bis(4-oxyphenyl)butane, 1.1-bis(4-oxyphenyl)cyclohexane, and 2.2-bis(4-oxyphenyl)butane.

The amount of the resin specified above in the image-receiving layer is usually 1 to 80% by weight, preferably 3 to 50% by weight.

If this amount is less than 1% by weight, the effects of the present invention may not be fully exhibited.

When the above-specified resin is included in the image-receiving layer together with the binder resin, the image density (transfer density) can be improved even without high thermal energy, unlike when these resins are not included.
It is possible to increase the

Not only that, the heat resistance has been definitely improved, and even if stored for a long period of time, color fading and color increase are suppressed, and the clarity of a single image is not likely to deteriorate.

The reason why such an effect can be obtained when the specific resin is used in combination with the binder resin is not entirely clear, or may be thought to be as follows.

It can be said that the main function of the binder resin is to accept and stop dyes.

It is true that the binder resins mentioned in the previous section (3) do not accept dyes at high concentrations, or they are insufficient in the points mentioned above, such as heat-resistant image storage properties.

On the other hand, when the above-mentioned specific resin is used in combination with the binder resin listed in the previous section (1), the improvement effect is first manifested.

This is thought to be due to the combination of a specific resin or the aid of dye diffusion, allowing the dye to penetrate deep into the image-receiving layer, resulting in increased sensitivity and improved heat-resistant image storage stability.

Is it possible to diffuse the dye deep into the image-receiving layer by simply adding a plasticizer (for example, DOP), but on the other hand, does it significantly impair the fixation of an image?
IJJ has been clarified through research by the present inventors.

(2) Additives Release agents, antioxidants, UV absorbers, light stabilizers, fillers, pigments, and plasticizers as sensitizers may be added to the image-receiving layer.

The release agent can improve the releasability between the ink sheet for thermal transfer recording and the image receiving sheet for thermal transfer recording.

Such release agents include silicone oil (including what is called silicone resin), polyethylene wax, etc.
Examples include solid waxes such as wax, amide wax, and Teflon balater; fluorine-based and phosphoric acid ester-based surfactants, among which silicone oil is preferred.

There are two types of silicone oil: a type that is simply added (simple addition type) and a type that is cured or reacted (hardening reaction type).

In the case of a simple addition type, it is preferable to use modified silicone oil in order to improve compatibility with the binder.

As modified silicone oil, polyester modified silicone resin (or silicone modified polyester resin)
, acrylic-modified silicone resin (or silicone-modified acrylic resin), urethane-modified silicone resin (or silicone-modified urethane resin), cellulose-modified silicone resin (or silicone-modified cellulose resin), alkyd-modified silicone resin (or silicone-modified alkyd) resin), epoxy-modified silicone resin (or silicone-modified epoxy resin), etc.

That is, polyester-modified silicone resin containing polysiloxane resin in the main chain and copolymerized with polyester in a proton-like manner, silicone-modified polyester resin having dimethylpolysiloxane moiety as a side chain bonded to the main chain of Bossester, Block copolymers, alternating copolymers, kraft copolymers, random copolymers, etc. of dimethylpolysiloxane and polyester can also be used as modified silicone oils or resins.

In particular, in the present invention, it is preferable to add a polyester-modified silicone resin.

Typical polyester-modified silicone resins include, for example, a copolymer of diol and dibasic acid, or a block copolymer of polyester, which is a ring-opening polymer of caprolactone, and dimethylbosiloxane (both ends or one end of dimethylbosiloxane). (or conversely, contains a copolymer in which the above polyester is blocked with the above polyester or dimethylpolysiloxane), or with the above polyester as the main chain and (dimethyl)polysiloxane in the side chain. Examples include copolymers formed by bonding.

The amount of these midline addition type silicone oils can vary depending on the type, so it cannot be determined uniformly. The amount is from 0.5 to 50% by weight, preferably from 1 to 20% by weight, based on the binder.

Curing reaction type silicone oils include reaction curing type,
Examples include photo-curing type and catalyst-curing type.

Reaction-curing silicone oils include those obtained by reaction-curing amino-modified silicone oil and epoxy-modified silicone oil.

In addition, as catalyst curing type or photo curing type silicone oil, KS-705F-PS, KS-705F-PS-
1, KS-770-PL-3 [Both are catalytic curing silicone oils: Shin-Etsu Chemical Co., Ltd., KS-72
0, KS-774-PL-3 [all photocurable silicone oils: 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 binder for the image-receiving layer.

Note that a release agent layer can also be provided by dissolving or dispersing the above-mentioned release agent in a suitable solvent and applying the solution to a part of the surface of the image-receiving layer, followed by drying.

Next, as the antioxidant, JP-A-59-18278
5, 60-1:107:Is, JP-A-1-1273
Examples include the antioxidants described in 87, etc., and compounds known to improve image durability in photographs and other image recording materials.

As the UV absorber and light stabilizer, JP-A-59-
158287, 63-74686, 6:1-14
5089, 59-196292, 62-2295
94, 63-122596, 61-28:1595
, JP-A-1-204788, etc., and compounds known to improve image durability in photographs and other image recording materials.

Examples of the filler include inorganic fine particles and organic resin particles.

These inorganic fine particles include silica gel, calcium carbonate,
Examples of the fine particles include titanium oxide, acid clay, activated clay, alumina, etc., and examples of the fine particles include resin particles such as fluororesin particles, guanamine resin particles, acrylic resin particles, and silicone resin particles. These inorganic
It is preferable that the organic resin particles be added in an amount of 0.1 to 70% by weight depending on the specific gravity.

Typical examples of the pigment include titanium white I, calcium carbonate, zinc oxide, and barium sulfate.

Examples include silica, talc, clay, kaolin, activated clay, and acid clay.

Examples of the plasticizer include phthalate esters (for example, dimethyl phthalate, dibutyl phthalate, dioctyl phthalate,
(didecyl phthalate, etc.), adipate esters (dioctyl adipate, methyl lauryl adipate, di-2-ethylhexyl adipate, ethyl lauryl adipate, etc.), other oleic acid esters, succinic acid esters, maleic acid esters, Sepatic acid esters, citric acid esters, epoxy stearic acid esters, phosphate esters such as triphenyl phosphate and tricresyl phosphate, and glycols such as ethyl phthalyl ethyl ethyl cricolate and butylphtawaltzyl cricolate. Examples include esters.

In the present invention, the total amount of additives added is usually in the range of 0.1 to 50% by weight based on the binder for the image-receiving layer.

■Formation of the image-receiving layer The image-receiving layer is prepared by, for example, dispersing or dissolving the components forming the image-receiving layer in a solvent to prepare a coating solution for the image-receiving layer, and applying this coating solution for the image-receiving layer to the surface of the base material. Drying coating methods,
By a lamination method, etc., in which a mixture having components forming the image receiving layer is melt-extruded and laminated on the surface of a base material,
Can be formed.

The solvent used in the above coating method is toluene.

Cyclohexane, pentane, hexane, methyl ethyl ketone, ethyl acetate, etc. - mention may be made of organic solvents.

Further, when employing the above-mentioned lamination method which can be applied as a dispersed emulsion using an aqueous system, a coextrusion method may also be employed if the base material is a synthetic resin as described later.

The image receiving layer may be formed over the entire surface of the base material, or may be formed on a part of the surface.

The thickness of the image receiving layer is generally 3 to 504 m, preferably 5 to 504 m.
It is about 15 Bm.

On the other hand, since the image-receiving layer is self-supporting, when the image-receiving layer itself is used to form an image-receiving sheet for thermal transfer recording, the thickness of the image-receiving layer is usually 60 to 200 μm, preferably 90 to 100 μm.
It is about 50 μm.

-Base material- Examples of the base material include paper, coated paper 1 synthetic paper (polypropylene, polystyrene, or synthetic paper).

Composite materials made by gluing them together with paper), white polyethylene terephthalate base film, transparent 11 polyethylene terephthalate base film, RC vapor, etc. can be suitably used.

The thickness of the base material is usually 30 to 300 μm, preferably 80 μm.
~200 km.

-Other Layers- A release layer may be laminated on the surface of the image-receiving sheet for thermal transfer recording, with one release layer.

This layer can be formed from the silicone resin or modified silicone resin.

The thickness of this release layer is usually 0.1 to IILm.

Further, a cushion layer may be provided between the base material and the image-receiving layer of the image-receiving sheet for thermal transfer recording in order to reduce noise and transfer and record an image corresponding to image information with good reproducibility.

Examples of the material constituting this cushion layer include urethane resin, acrylic resin, ethylene resin, butadiene rubber, and epoxy resin.

The thickness of the cushion layer is usually preferably 1 to 25 pm.

(II) Ink sheet for thermal transfer recording The ink sheet for thermal transfer recording has a basic structure in which an ink layer is laminated on a support.

This ink layer is not limited to a single layer, but may be composed of multiple layers.

One Ink Layer - The ink layer basically contains a heat diffusible dye and a binder.

(2) Heat-diffusible dye There are no particular restrictions on the heat-diffusible dye as long as it is heat-diffusible or non-flammable.

Examples of heat-diffusible dyes include cyan dyes, magenta dyes, and yellow dyes.

As the cyan dye, JP-A-59-78896;
No. 59-227948, No. 60-24966, No. 6
05356: No. 1, No. 60-1: 10735, No. 60
-1: No. 11292, No. 60-2: 19289, No. 6
1-19: No. 196, No. 61-22993, No. 61-
No. 31292, No. 61-31467, No. 61-359
No. 94, No. 61-49893, No. 61-148259
No. 62-191191, No. 63-91288,
Examples include naphthoquinone dyes, anthraquinone dyes, azomethine dyes, etc., which are described in various publications such as No. 63-91287, No. 1, No. 63-29079:1.

Examples of the magenta dye include JP-A-59-78896, JP-A-60-30392, and JP-A-60-:103.
No. 94, JP-A-60-25:159S, JP-A-61-
No. 252190, #Opening/Closing 6:l-5992, JP-A No. 6
Examples include anthraquinone dyes, azo dyes, azomethine dyes, etc., which are described in publications such as JP-A No. 1-205288, JP-A-64-159, and JP-A-64-6:1194.

Examples of yellow pigments include JP-A-59-78895, JP-A-60-27594, JP-A-60-31560,
JP-A-60-5: No.l565, JP-A-61-12394
Examples include methine dyes, azo dyes, quinophthalone dyes, and anthrisothiazole dyes, which are described in various publications such as JP-A No. 63-122594.

Further, as the heat-diffusible dye, an azomethine dye obtained by a coupling reaction of a compound having an open-chain or closed-chain active methylene group with an oxidized product of a P-phenylenediamine derivative or an oxidized product of a P-aminophenol derivative; and oxidized products of phenoldiamine derivatives or p-
Indoaniline dyes obtained by color printer reaction with aminophenol derivatives can also be suitably used.

- The thermally diffusive dye may be any of yellow, magenta, and cyan dyes as long as the image to be formed is monochromatic.

Furthermore, depending on the tone of the image to be formed, it may contain two or more of the three types of heat-diffusible dyes or other dyes.

The amount of the heat-diffusible dye used is usually 0.1 to 20 g, preferably 0.2 to 5 g per 1 m'' of support.

(2) Binder As the binder used in the ink layer, it is possible to use resins known in the field of thermal transfer recording, but preferred are acetal resins and/or cellulose resins described below.

First, as the acetal resin, there are various compounds depending on the degree of acetalization and the content of acetyl groups, and representative examples include polyvinyl acetoacetal and polyvinyl butyral.

Among acetal resins, a polymerization degree of 30 is preferable.
It is an acetal resin having a glass transition point (Tg) of 0 or more, preferably 1500 to 8000, a glass transition point (Tg) of 50 to 200°C, and a degree of acetalization of mol % or more and acetyl group mol % or less.

The product names of acetal resins that meet these conditions include KS-1, KS-5, S-8, BL-1, and B.
L-2, BL-3, BL-S.

BM-1, 8M-2, BM-5, 8M-5, BH-3,
Examples include BX-1 [both manufactured by Building Block Chemical Industry Co., Ltd.].

Examples of cellulose resins include nitrocellulose, ethylcellulose, hydroxyethylcellulose, ethylhydroxyethylcellulose, hydroxypropylcellulose, methylcellulose, cellulose acetate,
Examples include cellulose acetate.

Among these cellulose resins, nitrocellulose is particularly preferred.

Furthermore, among the nitrocelluloses, preferred for the purposes of the present invention are those with a nitrogen content of 10.7 to 12.2%, based on the test method of JIS K-6703.
Polymerization degree: 35-110, viscosity: 1.0-6.2
Sho (measured at 25.0% solids), 3 to 8 seconds (measured at 20% solids)
．． 0% Te 0 constant), 1.5-500 Pj (v; 1 form IZ, 2X"C' measurement measurement, 1.1-5.2 seconds (measured at 30% solid content), 100-+40 c p s (
1.5 g of dry nitrocellulose to 100 cc of butyl acetate
It is nitrocellulose with a value of ), measured when dissolved in .

The product names of nitrocellulose that meet these conditions are HIGI/16. HIGI/8, HIGI/4
,HIGI/2,HIGl,HIO2,HIO2,HI
O2(1, HIO2(1, HIG+20.HIG500
．． LIGI/8, LIGI/4, LIGI/2, SL-
1, HX 1000. H1200 mouth, clear H1/
4. Tyfubu H1/2 etc. [all manufactured by Asahi Karit, Co., Ltd.
There is a made one.

Next, in addition to the acetal resin and cellulose resin, binders conventionally known in the thermal transfer recording field include, for example, acrylic resin, methacrylic resin, polyvinyl alcohol, polyvinyl formal, polyvinyl chloride, polyvinyl ether, polyvinylpyrrolidone, and polystyrene. 2 polystyrene copolymer, ionomer resin, etc.

These may be used alone or in combination of two or more.

Further, the weight ratio of the binder and the heat-diffusible dye in the ink layer is preferably in the range of 1:10 to 10:1.

(2) Additives Various additives may be added to the ink layer as necessary.

The additives include fluororesin, surfactant, peeling compounds such as waxes, and fine metal powder.

Examples include fillers such as metal oxides, silica gel, carbon black, and fine resin powder, and curing agents that can react with binder components (for example, radiation-active compounds such as isocyanates, acrylics, and epoxies).

Furthermore, in order to promote transcription, for example, JP-A-59-1
It is possible to use heat-melting substances such as waxes and higher fatty acid esters described in No. 06997 and the like.

The amount of additives to be added cannot be uniformly determined depending on the type of additive and the purpose of addition, or the amount of additives as a whole is usually in the range of 20% by weight or less based on the binder.

[Co., Ltd.] Forming an ink layer The ink layer is prepared by dispersing or dissolving the heat-diffusible dye, binder, and optional components added as necessary in a solvent to prepare a coating solution for forming a heat-sensitive layer. It can be formed by coating this coating liquid onto a support and then applying it.

The binder may be used not only by dissolving -M or two or more thereof in a solvent, but also by dispersing it in a latex form.

The above-mentioned solvents include water, alcohols (e.g. ethanol, propatool), cellosolves (e.g. methyl cellosolve, ethyl cellosolve, etc.), aromatics (e.g. toluene, xylene, chlorobenzene, etc.), ketones (e.g.
Examples include acetone, methyl ethyl ketone, etc.), esters (eg, ethyl acetate, methyl acetate, etc.), needles (eg, tetrahydrofuran, dioxane, etc.), and chlorinated solvents (eg, chloroform, trichloroethylene, etc.).

These solvents may be used alone.

Two or more types can be used in combination.

For the above-mentioned coating, commonly known surface sequential coating using a gravure roll, extrusion coating, wire bar coating, roll coating, etc. can be used.

The ink layer has a thickness of 0.2 to 10 gm, and even 0.2 to 10 gm on the support.
．． It is preferable to form the ink layer to a thickness of 3 to 34 m.The ink layer includes a yellow ink layer containing a binder resin and a yellow dye, a magenta ink layer containing a binder resin and a magenta dye, and a cyan ink layer containing a binder resin and a cyan dye. Preferably, the ink layer is formed on the support in a constant manner in a planar direction.

In addition to the three ink layers arranged along the surface direction, a black ink layer containing a black image forming substance may be interposed between any two layers adjacent in the surface direction.

In particular, with respect to the black ink layer, clear characters and images can be obtained with either the diffusion transfer type or the melt transfer type.

As a support, any support may be used as long as it has good dimensional stability and can withstand the heat of a heat source such as a thermal head during image recording. Heat resistant plastic films such as , polyethylene terephthalate, polyamide, polycarbonate, borisa J refone, borhihi' 2 J real alcohol cellophane, polystyrene are suitable.

The thickness of the support is preferably in the range of usually 2 to 10 jLm.

-Other Layers- An undercoat layer may be provided between the ink layer and the support in order to improve adhesiveness and the like.

Furthermore, an anti-fusing layer may be provided on the ink layer.

Its thickness is usually 0.1 to 2 pLm, preferably 0.2 to 2 pLm.
It is in the range of 0.8 gm.

Further, the back surface of the support (the side opposite to the ink layer) may have an anti-sticking layer for the purpose of preventing adhesion, sticking, and wrinkles from occurring on the head or support.

The thickness of this anti-sticking layer is preferably in the range of 0.1 to 1 m.

Further, by forming perforations on the heat-sensitive sheet for thermal transfer recording, or providing detection marks for detecting the positions of areas with different hues, convenience in use can be improved.

(m) Image formation To perform image formation, the image-receiving sheet for thermal transfer recording of the present invention and the ink sheet for thermal transfer recording are superimposed so that the image-receiving layer of the former and the ink layer of the latter are in contact with each other. Then, thermal energy is applied imagewise to this interface.

Then, the heat-diffusible dye in the ink sheet for thermal transfer recording vaporizes or sublimates in an amount corresponding to the applied thermal energy, and migrates to the image-receiving sheet for thermal transfer recording.
It is fixed on the image-receiving layer to form an image there.

A thermal head is generally used as the heat source for providing the thermal energy, but other known heat sources such as a laser beam, an infrared flash, and a thermal pen may also be used.

Thermal energy can be applied from the image receiving sheet for thermal transfer recording, from the ink sheet for thermal transfer recording, or from both sides.

However, from the viewpoint of effective use of thermal energy, it is preferable to carry out this process from the side of the ink sheet for thermal transfer recording.

Also, it is used for the purpose of controlling thermal energy to express the gradation of light and shade in images, or promoting the diffusion of dyes into image-receiving sheets for thermal transfer recording to ensure the expression of continuous gradations in images. It is preferable to apply thermal energy from the side of the image-receiving sheet for thermal transfer recording.

Furthermore, in the sense that the advantages of the above two methods can be enjoyed at the same time, it is preferable to carry out the recording from the side of the ink sheet for thermal transfer recording and the side of the image receiving sheet for thermal transfer recording.

When a thermal head is used as a heat source for providing thermal energy, the applied thermal energy can be varied continuously or in multiple stages by modulating the voltage or pulse width applied to the thermal head.

When using laser light as a heat source, the thermal energy provided can be changed by changing the amount of laser light and the irradiation area.

If a dot generator with a built-in acousto-optic element is used, it is also possible to generate thermal energy corresponding to the size of the halftone dots.

In addition, when using laser light as a heat source.

It is desirable that the ink sheet for heat-sensitive transfer recording and the image-receiving sheet for heat-sensitive transfer recording be brought into close contact with each other, and the surface to be irradiated with laser light may be colored, for example, black to improve absorption of the laser light.

When using an infrared flash lamp as a heat source, it is preferable to irradiate the lamp through a colored layer such as black, as in the case of using laser light.

In addition, irradiation with this lamp can be performed through a pattern or halftone dot pattern that continuously expresses the shading of an image such as black, and the colored layer such as black on the - side corresponds to the negative of the above pattern. This can also be done in combination with a negative pattern.

When thermal energy is applied in this way, an amount of dye corresponding to the amount of energy is thermally transferred from the thermal sheet for thermal transfer recording to the image receiving layer of the image receiving sheet for thermal transfer recording, and a one-color image is recorded there. However, if you replace the heat-sensitive sheet for heat-sensitive transfer recording, you can also obtain a color photographic image.

For example, by sequentially replacing yellow, magenta, cyan, and, if necessary, black thermal transfer recording ink sheets and performing thermal transfer for each color, it is possible to obtain a color photographic color image consisting of a combination of each color.

Note that instead of using ink sheets for thermal transfer recording of each color as described above, it is also possible to use a first-order ink sheet.

That is, an ink sheet for thermal transfer recording is prepared in which areas are formed by coating each color in advance.

First, the yellow area is used to thermally transfer the yellow color separation image, and the magenta area is then used to thermally transfer the magenta color separation image.From then on, by sequentially repeating this operation, yellow, magenta, cyan, and And if necessary, thermally transfer the black and color separation images.

This method has the advantage that it is not necessary to replace the ink sheet for thermal transfer recording.

[Example] Next, the present invention will be explained in more detail based on Examples.

Note that in the following, "parts" represent "parts by weight."

(Example 1) A 94 m thick polyethylene terephthalate film [Toyobo Co., Ltd.] was used as a support. 2. A coating solution for forming a heat-sensitive layer having the following composition was applied to the surface treated with a surona of S PET by a wire bar coating method to a thickness of l after drying.
Apply it to #Lm, dry it, and apply it to the back side that has not been corona treated: r-:/o: (X-4
1,4003A, manufactured by Shin-Etsu Silicone Co., Ltd.) with a dropper
, 2 drops were applied and spread over the entire surface, and a backside treatment coat was applied to obtain an ink sheet for thermal transfer recording.

Coating liquid for ink layer formation Dispersed dye [manufactured by Nippon Kayaku Co., Ltd., 4 parts Kayasect Fluor 136] Polyvinyl butyral 5 parts [JJL Suikagaku Kogyo Co., Ltd.] Co., Ltd., BX-1, degree of polymerization 1700] Methyl ethyl ketone...90 parts Cyclohexanone...5 parts Yubo FPG-150, manufactured by Synthetic Paper Co., Ltd., was coated with a coating solution for forming an image-receiving layer having the following composition onto a wire using a coating method, and then temporarily dried using a dryer, and then placed in an oven at a temperature of 100°C. After drying for 1 hour, an image-receiving sheet for thermal transfer recording was obtained, in which an image-receiving layer with a thickness of 5 #Lm was formed on synthetic paper.

Coating liquid for image-receiving layer formation Chlorinated polypropylene...4 parts Vinyl chloride-vinyl acetate copolymer...10PI (manufactured by Union Carbide Co., former VY) Methyl ethyl ketone...
...90 copies Next, the ink sheet for heat-sensitive transfer recording and the image-receiving sheet for heat-sensitive transfer recording are superimposed so that the surface of the ink layer of the former is in contact with the surface of the image-receiving layer of the latter,
Using a thermal head from the support side of the ink sheet for thermal transfer recording, output IW/dot and pulse width of 0.3 to 4.
One image was recorded by heating under conditions of 5 m5 ec and a dot density of 3 dots/mm.

After the image was recorded, the transfer density on the surface of the image-receiving layer of the image-receiving sheet for thermal transfer recording and the heat-resistant storage stability of one image were evaluated according to the following criteria.

The results are shown in Table 1.

Transfer density: The reflection density OD value was measured using an optical densitometer.

0...OD value is 2.0 or more.

△・・・OD value 1.7~2.0° X・　・　・・・OD value month, 7 or less.

Heat-resistant storage stability: The image-receiving sheet for thermal transfer recording on which an image was recorded was kept in an environment of 77° C. and 80% relative humidity for 3 days, and fluctuations in image density were observed.

When the variation in O- concentration is within 10%.

X - When the concentration fluctuation exceeds 10%.

(Example 2) The same procedure as in Example 1 was carried out except that the coating liquid for forming an image-receiving layer in Example 1 had the following composition.

The results are shown in Table 1.

Coating liquid for image-receiving layer formation Chlorinated paraffin...4 parts Polyester resin...10 parts [Toyobo jj! (
Byron 290, manufactured by Shin-Etsu Silicone Co., Ltd.] Amino-modified silicone oil: 0.125 parts [KF, manufactured by Shin-Etsu Silicone Co., Ltd.]
393] Epoxy modified silicone oil...0.1
25 parts [manufactured by Shin-Etsu Silicone Co., Ltd., X-22-343]
]Toluene・・・・・・・・・・・・57 parts Xylene・・・・・・・・・・・・13 parts Methyl ethyl ketone・・・・・・・・・6.3 parts 2 -Butanol...
・・・・・・・・・14 parts cyclohexanone・・・・・・
30 parts (Example 3) Same as Example 1 except that the composition of the coating liquid for forming the image receiving layer in Example 1 was changed to the following composition and the thickness of the image receiving layer was set to 1 gm. carried out.

The results are shown in Table 1.

Coating liquid for forming image-receiving layer Vinyl chloride-vinyl acetate copolymer...20 parts (manufactured by Union Carbide Co., Ltd., VYHH) Polyethylene oxide ・
......5 parts methyl ethyl ketone...
...100 parts cyclohexanone...
...50 parts (Comparative Example 1) The same procedure as in Example 2 was carried out except that in Example 1, the use of chlorinated paraffin, which was one of the components of the coating liquid for forming an image-receiving layer, was omitted.

The results are shown in Table 1.

Table 1 [Effects of the Invention] The image-receiving sheet for thermal transfer recording of the present invention can obtain a high-density image without using high thermal energy during thermal transfer, and the image can be easily removed after thermal transfer. Because it exhibits good heat resistance, it is possible to preserve clear, high-quality images for a long period of time.

[Brief explanation of drawings]

FIGS. 1A and 1B are cross-sectional views showing different image-receiving sheets for thermal transfer recording of the present invention. 1...Base material, 2...Receiving layer, 2a...Image receiving layer. 1st r! A (a)

Claims (2)

[Claims] (1) An image-receiving sheet for thermal transfer recording, comprising an image-receiving layer containing a binder resin selected from Group A below and a resin selected from Group B below. Group A: α-olefin resin, oxide of α-olefin resin, chlorinated product of α-olefin resin, paraffin wax, oxide of paraffin wax, chlorinated product of paraffin wax. Group B: vinyl chloride resin, polyester, polycarbonate. (2) The image-receiving sheet for thermal transfer recording according to claim 1, wherein the image-receiving layer contains a release agent.