JPH04308792A - Image receiving sheet for thermal transfer recording - Google Patents

Abstract

PURPOSE:To obtain an image receiving sheet for thermal transfer recording capable of preventing the occurrence of hickey caused by static charges at the time of image forming, having good transport properties, and preventing sticking. CONSTITUTION:In an image receiving sheet for thermal transfer recording consisting of an image receiving layer and a substrate, an image receiving sheet for thermal transfer recording provided with a laminate having thermoplastic resin layers on both surfaces of paper as a substrate and controlled in electrostatically charging so that the sheet resistance of said paper is lower than 10<10>OMEGA/square.

Description

[Detailed description of the invention]

0001

[Industrial Application Field] The present invention relates to an image-receiving sheet for thermal transfer recording, and more specifically, it is for thermal transfer recording that prevents white spots during image formation due to charging and has good conveyance properties that prevent mutual adhesion. Regarding the image receiving sheet.

0002

[Prior Art and Problems to be Solved by the Invention] In recent years, inkjet,
Color recording techniques using electrophotography, thermal transfer, etc. are being considered.

[0003] Among these, the thermal transfer method in particular has a number of advantages such as ease of operation and maintenance, ability to reduce the size of the device, and ability to reduce costs.

In this thermal transfer method, a transfer sheet having a meltable ink layer on a support is imagewise heated by a laser or a thermal head to melt and transfer the meltable ink layer onto a transfer sheet. Thermal diffusion transfer method (sublimation) uses a transfer sheet having an ink layer containing a heat-diffusible dye (for example, a sublimable dye) on a support to diffusely transfer only the heat-diffusible dye to the transfer sheet. There are two types: transfer method).

The latter thermal diffusion transfer method has recently been developed as a method that can control the gradation of an image by changing the amount of heat-diffusible dye transferred in response to changes in the thermal energy of the thermal head. Attention has been paid.

On the other hand, as an image-receiving sheet for thermal transfer recording used in the above-mentioned thermal transfer recording system, there can be mentioned an image-receiving layer laminated sheet containing a thermoplastic resin and a release material on the surface of a support.

In this image-receiving sheet for thermal transfer recording, a heat-diffusible dye is transferred to the image-receiving layer.

Conventionally, supports for image-receiving sheets for thermal transfer recording include paper, coated paper, synthetic paper (polypropylene, polystyrene, or a composite material made of paper and paper), white polyethylene terephthalate base film, transparent Polyethylene terephthalate base film, transparent polyethylene naphthalate base film,
Examples include white polyvinyl chloride base film, transparent polyvinyl chloride base film, and polyolefin-coated paper.

However, the support of the image-receiving sheet for thermal transfer recording is easily charged, and therefore the image-receiving layer thereof has a property of easily adsorbing dirt and dust.

[0010] If dirt or dust is adsorbed to the image-receiving layer, when the image-receiving layer and the ink layer are overlapped and the heat-diffusible dye is transferred, voids are created by the dirt or dust at the interface between the two layers, and as a result, the heat-diffusible dye is There is a problem in that the image is not transferred and wide white spots mainly due to dirt and dust appear on the image.

[0011] Furthermore, if the support is electrically charged, the transportability will be poor. For example, if image-receiving sheets for thermal transfer recording are stacked and stored, they tend to stick to each other, making it difficult to remove each sheet one by one. , two sheets are fed, and the handling is not easy due to poor handling.

[0012] Among the above supports, polyolefin-coated paper uses paper, so it has high heat resistance, less curling after printing, low manufacturing cost, and relatively low chargeability. It has its features. However, although the charging property is relatively small, it cannot be said to be sufficient.

The present invention has been made to improve the above situation.

The object of the present invention is to prevent white spots during image formation due to charging, to have good conveyance, to prevent sticking,
An object of the present invention is to provide an image-receiving sheet for thermal transfer recording that causes less curling after printing.

[0015]

[Means for Solving the Problems] To achieve the above object, the present invention provides a support made by laminating thermoplastic resin layers on both sides of inner paper having a surface specific resistance of 1010 Ω/□ or less.
This is an image-receiving sheet for heat-sensitive transfer recording, characterized in that it is formed by laminating image-receiving layers.

The present invention will be explained in detail below.

(1) Image-receiving sheet for thermal transfer recording The image-receiving sheet for thermal transfer recording of the present invention can be composed of a support and an image-receiving layer formed thereon.

-Support- The support used in the present invention is a laminate having thermoplastic resin layers on both sides of paper. A support having such a specific surface resistivity can be obtained by appropriately selecting the support and the thermoplastic resin, as detailed below.

1. Inner paper The inner paper constituting the support in the image-receiving sheet for thermal transfer recording of the present invention may be paper containing natural pulp as a main component.

[0020] As this natural pulp, wood pulp is preferable. As the wood pulp, chemical pulp, kraft pulp (sulfate pulp), sulfite pulp, bleached pulp, etc. can be suitably used.

[0021] In addition, during its manufacture, the inner paper contains softeners,
Additives such as paper strength agents, sizing agents, fillers, and fixing agents may be included. In addition, this inner paper includes paperboard, medium-quality paper, high-quality paper, art paper, coated paper, cast coated paper,
Kraft paper, synthetic resin emulsion impregnated paper, etc. can be used.

In the present invention, the surface specific resistance value of the inner paper is 10 10 Ω/□ or less, preferably 10 9 Ω/□ or less. When the surface specific resistance of the inner paper exceeds 1010 Ω/□, the support is likely to be charged.

Here, the surface resistivity value can be measured by using a surface resistivity meter on the exposed surface of the paper one minute after peeling off the thermoplastic resin layer from the support. On this occasion,
The surface resistivity value is measured under environmental conditions of a temperature of 25° C. and a relative humidity of 55%. When the support of the image-receiving sheet for thermal transfer recording is electrically charged, the image-receiving layer tends to attract dirt and dust. If dirt or dust is adsorbed to the image-receiving layer, when the ink layer and image-receiving layer are overlapped and the heat-diffusible dye is transferred, voids will be created at the interface between the two layers, causing the heat-diffusible dye to be transferred. Without,
A problem arises in that white spots, mainly caused by dirt and dust, appear in the image.

Furthermore, if the support is electrically charged, the transportability of the image-receiving sheet for thermal transfer recording becomes poor, and for example, when image-receiving sheets for thermal transfer recording are stored in piles, they tend to stick to each other. You may not be able to take out one sheet at a time, or you may have to feed two sheets, or the handling may be poor. By making the surface of the inner paper have a specific surface resistivity as described above, the above-mentioned problems can be solved.

[0025] In order to set the surface resistivity of the inner paper to the above-mentioned specific value, the inner paper may contain a conductive additive, and the tab size or size press may be used to control the chargeability of the surface of the inner paper. What is necessary is to perform antistatic treatment or adjust the moisture content in the inner paper.

The conductive additives include inorganic antistatic agents, such as alkali metal salts such as sodium chloride, potassium chloride, and lithium chloride, alkaline earth metal salts such as calcium chloride and barium chloride, tin oxide, and colloidal metals. Salts, conductive metal oxides such as zinc oxide and titanium oxide, organic antistatic agents, and water-soluble polymers such as sodium styrene maleate and alkali metal salts of cellulose derivatives.

These conductive additives can be used alone or in combination of two or more. In any case, the content of the conductive additive in the inner paper, the type of inner paper, the types of other additives, and their blending amount are determined as appropriate so that the surface resistivity specified in the present invention is achieved. be adjusted.

The moisture contained in the inner paper can be adjusted in the drying section of the paper machine centered around the drying cylinder. The inner paper used in the present invention is white, for example, Hunter paper.
It is preferable that the whiteness is in the range of L≧85, a=−1 to 3, and b=−1 to −7, particularly L≧90, a=0.5 to
1.5, preferably in the range of b=-3 to -5.

[0029] Hunter whiteness is determined by JIS Z
The spectral reflectance can be measured using a spectrophotometer according to JIS Z 8722 and determined based on JIS Z 8730. When the inner paper has a whiteness within the above range, the clarity of the image can be improved. In order to bring the whiteness of the inner paper within the above range, it may be adjusted by bleaching the pulp used in paper making, using a fluorescent brightener, using pigments, etc.

Further, the inner paper used in the present invention preferably has a smoothness of, for example, Bekk smoothness of 100 (unit: seconds) or more.

[0031] Beck smoothness is JIS P 8119
It can be measured with a Beck tester according to the following.

If an inner paper with low smoothness and a rough surface is used, the surface of the support will have many irregularities and the heat-diffusible dye will not be transferred well.On the other hand, if a inner paper with a high smoothness is used. Since the unevenness on the surface of the support is reduced, an image with good quality can be obtained.

[0033] The smoothness of the inner paper can be adjusted to a desired value by, for example, calendering the paper using an on-machine calender in a paper machine or a super calender after paper making.

Further, the inner paper used in the present invention preferably has a Taber stiffness of 7 or more in the paper making direction and 3 or more in the perpendicular direction, particularly 10 to 20 in the paper making direction and 5 to 10 in the perpendicular direction. It is preferable that When the rigidity of the inner paper is within the above range, the transportability of the image-receiving sheet for thermal transfer recording is improved and handling becomes easy.

[0035] The stiffness can be measured using, for example, the Taber stiffness meter (
Teledyne Company-USA).

On the other hand, the inner paper used in the present invention usually has a thickness of 100 μm or more, and preferably 150 to 250 μm.

[0037] Furthermore, the inner paper used in the present invention is preferably surface-treated, and corona discharge treatment is particularly preferred as the surface treatment. By performing the corona discharge treatment, it is possible to improve the adhesion of the thermoplastic resin layer, which will be described next.

2. Thermoplastic resin layer The binder constituting the thermoplastic resin layer laminated on both sides of the inner paper is not particularly limited as long as it is a thermoplastic resin.

Examples of the thermoplastic resin include polyolefin resins, polyester resins, and polystyrene resins. Particularly preferred are polyolefin resins. Specific examples of preferred polyolefin resins include polyethylene resins and polypropylene resins. These resins have excellent adhesion to the ink sheet.

[0040] When a layer consisting of one or more of these thermoplastic resins is laminated on the upper surface of the paper, the surface of the support becomes smooth and the quality of transfer is improved, and moisture-proofing and
Provides waterproof function, water resistance, and moisture resistance function. Also,
When a layer of these thermoplastic resins is laminated on the lower surface of the inner paper, the moisture proofing, waterproofing, water resistance, and moisture resistance of the support can be further improved.

[0041] If the thermoplastic resin layer is laminated on only one side of the inner paper, the support is likely to curl, but in the present invention, since the thermoplastic resin layer is laminated on both sides of the inner paper, curling is prevented. can be prevented.

[0042] The thickness of the thermoplastic resin layer in the present invention is 5
It is preferably within the range of ~35 mm.

3. Manufacturing method of support The support of the image-receiving sheet for thermal transfer recording of the present invention is prepared by forming thermoplastic resin layers on both sides of inner paper by a method such as extrusion lamination or dry lamination of thermoplastic resin. It can be manufactured by laminating layers.

[0044] The thickness of the support is usually 20 to 300 μm.
, preferably 30 to 300 μm.

Further, in the support of the present invention, an adhesive layer may be provided between the inner paper and the thermoplastic resin layers provided on both sides of the inner paper.

A back coat layer can also be provided on the lower surface of the thermoplastic resin layer provided on the lower surface of the inner paper.

-Image-receiving layer- The image-receiving layer can be formed from only a binder. Moreover, depending on the case, it can also be formed from a binder and various additives.

1. Binder The binder includes, for example, polyvinyl chloride resin,
Copolymer resins of vinyl chloride and other monomers (such as vinyl acetate), polyester resins, acrylic esters, polyvinylpyrrolidone, polycarbonates, cellulose triacetate, styrene acrylate resins, vinyl toluene acrylate resins, polyurethane resins, polyamide resins, Examples include urea resin, polycaprolactone resin, styrene-maleic anhydride resin, and polyacrylonitrile resin.

The various resins mentioned above may be newly synthesized and used, but commercially available products may also be used.

For example, commercially available polyester resins include Vylon 200, Vylon 290, Vylon 600 [all manufactured by Toyobo Co., Ltd.], KA-1038C [manufactured by Arakawa Chemical Co., Ltd.] 220, and TP235 [all manufactured in Japan]. [manufactured by Synthetic Co., Ltd.] etc. can be used.

Among the binders, vinyl chloride copolymer resins typified by vinyl chloride-vinyl acetate copolymer resins, polyvinyl chloride resins, polyester resins, and the like are preferred.

The vinyl chloride-vinyl acetate copolymer resin preferably has a vinyl chloride component content of 85 to 97% by weight and a degree of polymerization of about 200 to 800.

The vinyl chloride-vinyl acetate copolymer resin used in the present invention does not necessarily have to be composed only of vinyl chloride components and vinyl acetate components, and may contain vinyl alcohol components and maleic components as long as it does not impede the purpose of the present invention. It may also contain an acid component or the like.

Examples of such vinyl chloride-vinyl acetate copolymers include S-LEC A, S-LEC C, S-LEC M [manufactured by Sekisui Chemical Co., Ltd.], Vinyrite VACH, Vinylyte VYHH, Vinylyte VMCH,
Viny Light VYHD, Viny Light VYLF, Viny Light VYNS, Viny Light VMCC, Viny Light VMCA,
Vinilite VACD, Vinilite VERR, Vinilite VROH (manufactured by Union Carbide), Denkabinir 1000GKT, Denkabinir 1000L, Denkabinir 1000CK, Denkabinir 1000A, Denkabinir 1000LK2, Denkabinir 1000AS,
Denkabinir 1000MT2, Denkabinir 1000
CSK, Denkabinir 1000CS, Denkabinir 10
00GK, Denkabinir 1000GSK, Denkabinir 1000GS, Denkabinir 1000LT3, Denkabinir 1000D, Denkabinir 1000W [manufactured by Denka Kagaku Kogyo Co., Ltd.], and the like.

In any case, from the viewpoint of physical properties, resins with glass transition points (Tg) in the range of -20 to 150°C, particularly 30 to 120°C, are suitable as binders for the image-receiving layer.
It is preferable to use a resin having an Mw in the range of .degree.

[0056] In forming the image-receiving layer, the above-mentioned various resins utilize their reactive active sites (if there are no reactive active sites, they are added to the resin), and radiation, heat, moisture, catalysts, etc. It may be crosslinked or cured by, for example.

In that case, a radiation active monomer such as epoxy or acrylic, or a crosslinking agent such as isocyanate can be used. 2. Additives Antioxidants, UV absorbers, light stabilizers, fillers (inorganic fine particles, organic resin particles), and pigments may be added to the additive image-receiving layer. Furthermore, a plasticizer or the like may be added as a sensitizer.

[0058] As the antioxidant, JP-A-59-1
No. 82785, No. 60-130735, JP-A-1-1
Examples include antioxidants described in various publications such as No. 27387, and compounds known to improve image durability in photographs and other image recording materials.

[0059] As the UV absorber and light stabilizer,
JP-A-59-158287, JP-A No. 63-74686,
No. 63-145089, No. 59-19692, No. 6
No. 2-229594, No. 63-122596, No. 61
Compounds described in publications such as No.-283595 and JP-A No. 1-204788, and compounds known to improve image durability in photographs and other image recording materials can be mentioned.

[0060] Examples of the filler include inorganic fine particles and organic resin particles.

Examples of the inorganic fine particles include silica gel, calcium carbonate, titanium oxide, acid clay, activated clay, alumina, etc., and examples of the organic fine particles include fluororesin particles, guanamine resin particles, acrylic resin particles, silicone resin particles, etc. The following resin particles can be mentioned. These inorganic/organic resin particles vary depending on their specific gravity, but are 0.1
Addition of ~70% by weight is preferred.

Typical examples of the pigment include titanium white, calcium carbonate, zinc oxide, barium sulfate, silica, talc, clay, kaolin, activated clay, and acid clay.

[0063] As the plasticizer, 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.), and other oleic acids. acid esters,
Succinic acid esters, maleic acid esters, sebacic acid esters, citric acid esters, epoxy stearic acid esters, phosphoric acid esters such as triphenyl phosphate and tricresyl phosphate, ethyl phthalyl ethyl glycolate and glycol esters such as butylphthalyl butyl glycolate.

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.

(2) Production of image-receiving sheet for thermal transfer recording The image-receiving sheet for thermal transfer recording of the present invention is prepared by preparing a coating liquid for the image-receiving layer by dispersing or dissolving the components forming the image-receiving layer in a solvent. It can be manufactured by a coating method in which the image-receiving layer coating liquid is applied to the surface of a support and dried.

The image receiving layer can also be produced by a lamination method in which a mixture containing the components forming the image receiving layer is melt extruded and laminated onto the surface of a support.

Examples of the solvent used in the coating method include conventionally known solvents such as water, alcohol, methyl ethyl ketone, toluene, dioxane, and cyclohexanone.

[0068] When employing the lamination method, a coextrusion method may also be employed.

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

The thickness of the image-receiving layer formed on the surface of the support is generally about 2 to 50 μm, preferably about 5 to 20 μm.

Further, in the image-receiving sheet for thermal transfer recording of the present invention, a cushion layer may be provided between the support and the image-receiving layer.

[0072] When the cushion layer is provided, noise is reduced and an image corresponding to the image information can be transferred and recorded with good reproducibility.

In the present invention, when a support having polyethylene resin layers laminated on both sides of paper is used, a cushion layer is not necessary. However, when using a support with hard resin layers such as polyester resin laminated on both sides of paper, it is preferable to provide a cushion layer.

Examples of the material constituting the cushion layer include urethane resin, acrylic resin, ethylene resin, butadiene rubber, and epoxy resin. The thickness of the cushion layer is usually 1 to 50 μm, preferably 3 to 3 μm.
It is 0um.

Further, in the image-receiving sheet for thermal transfer recording of the present invention, a barrier layer or an intermediate layer (adhesive layer) can be provided between the support and the image-receiving layer.

(3) Ink sheet for thermal transfer recording The ink sheet for thermal transfer recording can be composed of a support and an ink layer formed thereon.

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

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

[0079] As the cyan dye, JP-A-59-7
No. 8896, No. 59-227948, No. 60-249
No. 66, No. 60-53563, No. 60-130735
No. 60-131292, No. 60-239289, No. 61-19396, No. 61-22993, No. 6
No. 1-31292, No. 61-31467, No. 61-3
No. 5994, No. 61-49893, No. 61-1482
No. 69, No. 62-191191, No. 63-91288
Examples include naphthoquinone dyes, anthraquinone dyes, and azomethine dyes described in publications such as No. 63-91287 and No. 63-290793.

[0080] As the magenta dye, JP-A-59-
No. 78896, JP-A-60-30392, JP-A-60
-30394, JP 60-253595, JP 61-262190, JP 63-5992, JP 63-205288, JP 64-159, JP 64-63194 Examples include anthraquinone dyes, azo dyes, azomethine dyes, etc., which are described in various publications such as No.

[0081] As a yellow dye, JP-A-59-78
No. 896, JP-A-60-27594, JP-A-60-3
No. 1560, JP-A-60-53565, JP-A-61-
Examples include methine dyes, azo dyes, quinophthalone dyes, and anthrisothiazole dyes described in publications such as No. 12394 and JP-A-63-122594.

Particularly preferred as the heat-diffusible dye is a compound having an open-chain or closed-chain active methylene group and an oxidized product of a p-phenylenediamine derivative or a p-phenylenediamine derivative.
Azomethine dye obtained by a coupling reaction with an oxidized product of an aminophenol derivative and indoaniline obtained by a coupling reaction with an oxidized product of a phenol or naphthol derivative or a p-phenylenediamine derivative or an oxidized product of a p-aminophenol derivative. It is a pigment.

The heat-diffusible dye contained in the ink layer may be any of yellow, magenta, and cyan dyes as long as the image to be formed is monochromatic.

[0084] Depending on the tone of the image to be formed, the composition may contain two or more of the above three types of dyes or other heat-diffusible dyes.

[0085] The amount of the heat-diffusible dye used is usually 0.1 to 20 g, preferably 0.2 to 20 g per m2 of support.
It is 5g.

2. Binder Binders for the ink layer include cellulose resins such as ethyl cellulose, hydroxyethyl cellulose, ethyl hydroxyethyl cellulose, hydroxypropyl cellulose, methyl cellulose, cellulose acetate, and cellulose acetate butyrate; polyvinyl alcohol, polyvinyl formal, polyvinyl butyral, polyvinyl pyrrolidone,
polyester, polyvinyl acetate, polyacrylamide,
Examples include vinyl resins such as polyvinyl acetoacetal, styrene resins, styrene copolymer resins, polyacrylic esters, polyacrylic acids, and acrylic acid copolymers, rubber resins, ionomer resins, and olefin resins.

Among these resins, polyvinyl butyral, polyvinyl acetoacetal or cellulose resins, which have excellent acid resistance, are preferred.

[0088] The above-mentioned various binders can be used singly or in combination of two or more.

The weight ratio of the binder to the heat-diffusible dye is preferably 1:10 to 10:1, particularly preferably 2:8 to 8:2.

3. Other Optional Components Furthermore, various additives may be added to the ink layer within a range that does not impede the object of the present invention.

The additives include fillers such as fine metal powder, silica gel, metal oxide, carbon black, and fine resin powder, mold release agents such as silicone resin and fluororesin, and curing agents that can react with the binder component ( Examples include radiation active compounds such as isocyanates, acrylics, and epoxies.

Furthermore, examples of additives include heat-melting substances for promoting transfer, such as waxes and higher fatty acid esters, which are described in JP-A-59-106997.

-Support- Any support for the ink sheet for thermal transfer recording may be used as long as it has good dimensional stability and can withstand the heat generated by the thermal head during image formation, including condenser paper, glassine paper, etc. Heat-resistant plastic films such as tissue paper, polyethylene terephthalate, polyethylene naphthalate, polyamide, polycarbonate, polysulfone, polyvinyl alcohol, cellophane, and polystyrene can be used.

The thickness of the support is preferably 2 to 10 μm, and the support has a subbing layer for the purpose of improving adhesion with the binder and preventing transfer and dyeing of the dye to the support. You can leave it there.

Furthermore, the back side of the support (the side opposite to the ink layer)
A backing layer may be provided for purposes such as running stability, heat resistance, and antistatic properties.

[0096] The thickness of this backing layer is usually 0.1~
It is 1 μm.

[0097] There is no particular restriction on the shape of the support;
For example, it can be of any shape, such as wide sheets or films, or narrow tapes or cards.

(4) Production of ink sheet for thermal transfer recording The ink sheet for thermal transfer recording is prepared by dispersing or dissolving the various components forming the ink layer in a solvent to prepare a coating liquid for forming the ink layer. It can be manufactured by coating this on the surface of a support and drying it.

[0099] The above-mentioned binders are used by dissolving one or more of them in a solvent or dispersing them in a latex form.

[0100] Examples of the solvent include water, alcohols (eg, ethanol, propanol), cellosolves (eg, methyl cellosolve, ethyl cellosolve), aromatics (
(e.g., toluene, xylene, chlorobenzene), ketones (e.g., acetone, methyl ethyl ketone), ester solvents (e.g., ethyl acetate, butyl acetate, etc.), ethers (e.g., tetrahydrofuran, dioxane), chlorinated solvents (e.g., chloroform, trichloroethylene)
etc.

[0101] For the above-mentioned coating, conventional methods such as a surface sequential coating method using a gravure roll, an extrusion coating method, a wire bar coating method, a roll coating method, etc. can be employed.

[0102] The ink layer may be formed as a layer containing a monochromatic heat-diffusible dye on the entire surface or a part of the surface of the support, or may be formed as a layer containing a monochromatic heat-diffusible dye, or a yellow ink layer containing a binder and a yellow dye. A magenta ink layer containing a binder and a magenta dye and a cyan ink layer containing a binder and a cyan dye are formed on the entire surface or a part of the surface of the support in a constant repetition along the plane direction. You can leave it there.

The thickness of the ink layer thus formed is usually 0.2 to 10 μm, preferably 0.3 to 3 μm.
It is μm.

[0104] In the present invention, convenience in use can be made by forming perforations on the ink sheet for thermal transfer recording, or providing detection marks for detecting the positions of areas with different hues. .

The ink sheet for thermal transfer recording is not limited to the structure consisting of a support and a heat-sensitive layer formed thereon, and other layers may be formed on the surface of the ink layer.

For example, an overcoat layer may be provided for the purpose of preventing set-off (blocking) of the heat-diffusible dye.

(5) Image formation (thermal transfer recording) To form an image, the ink layer of the ink sheet for thermal transfer recording and the image receiving layer of the image receiving sheet for thermal transfer recording of the present invention are superimposed, and the ink layer and Image-wise thermal energy is applied to the image-receiving layer.

In this way, the heat-diffusible dye in the ink layer vaporizes or sublimates in an amount corresponding to the applied thermal energy, moves to the image-receiving layer side, and is received. As a result, an image is formed on the image receiving layer.

[0109] As the heat source for providing the thermal energy,
A thermal head is generally used, but other known devices such as a laser beam, an infrared flash, and a thermal pen can also be used.

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

[0111] When using laser light as a heat source for providing thermal energy, the heat energy provided can be changed by changing the amount of laser light and the irradiation area.

[0112] In this case, in order to facilitate laser light absorption, a laser light absorbing material (for example, in the case of a semiconductor laser, carbon black, an infrared absorbing substance, etc.) may be present in the ink layer or near the ink layer.

When using a laser beam, it is preferable to bring the ink sheet for thermal transfer recording and the image-receiving sheet for thermal transfer recording into close contact with each other.

[0114] If a dot generator incorporating an acousto-optic element is used, thermal energy can be applied depending on the size of halftone dots.

[0115] When an infrared flash lamp is used as a heat source for providing thermal energy, heating is preferably performed through a colored layer such as black, as in the case of using laser light.

[0116] Alternatively, heating may be performed through a pattern or halftone dot pattern that continuously expresses the shading of an image, such as black, or a colored layer such as black on one side and a negative of the above pattern. Heating may be performed in combination with negative patterns.

Thermal energy may be applied from the ink sheet side for thermal transfer recording, from the image receiving sheet side for thermal transfer recording, or from both sides, but priority is given to effective use of thermal energy. If so, it is desirable to do so from the ink sheet side for thermal transfer recording.

[0118] By the above thermal transfer recording, a one-color image can be recorded on the image-receiving layer of an image-receiving sheet for thermal transfer recording, but according to the method described below, it is possible to obtain a color photographic color image consisting of a combination of various colors. You can also do it.

For example, by sequentially replacing yellow, magenta, cyan, and, if necessary, black thermal transfer recording sheets and performing thermal transfer according to each color, a color photo-like color image consisting of a combination of each color is obtained. You can also do that.

[0120] In addition, the following method is also effective.

That is, instead of using ink sheets for heat-sensitive transfer recording of each color as described above, an ink sheet for heat-sensitive transfer recording that has areas formed in advance by painting each color is used.

[0122] First, the yellow area is used to thermally transfer the yellow color separation image, and then the magenta area is used to thermally transfer the magenta color separation image. , and, if necessary, a method of thermally transferring the black color image in this order.

[0123] Although it is possible to obtain a color photographic-like color image with this method, a further advantage is that this method does not require replacing the heat-sensitive sheet for heat-sensitive transfer recording as described above. There is.

[0124]

[Example] Canadian Standard Freeness (JI)
S P-8121-76) 20% by weight of softwood bleached sulfite pulp (NBSP) beaten to 250ml and 80% by weight of hardwood bleached sulfite pulp (LBKP) beaten to Canadian standard freeness 280ml, and this mixture The pulp is fed to a Fourdrinier paper machine and the basis weight is 14
A base paper with a density of 0 g/m2 and a tension of 1.05 g/m2 was made. At this time, the following paper-making additives were used in the following amounts based on the absolute dry weight of the pulp.

[0125] Papermaking additives:
Cationized starch・・・・・・・・・・・・・・・
・・・・・・2.0% Alkyl ketene dimer resin・・・・・・・・・・・・0.4% Anionic polyacrylamide resin・・・・・・・・・・・・・・・
・0.1% hydrin resin・・・・・・・・・・・・
・・・・・・・・・・・・0.7% Caustic soda...
・・・・・・・・・Adjust the pH to 7.5.

[0126] During the papermaking process, four types of base paper samples A to D were produced by adjusting the water removal rate in the drying section, which is mainly a drying cylinder.

[0127] Also, counting from the press side of the drying section, 75
% position, mix carboxyl-modified polyvinyl alcohol and sodium chloride at a ratio of 2:1, and apply 5 g/m2 of the 5% size liquid obtained by dissolving this mixture in water onto both sides of the base paper. , 20 g/m2, to obtain base paper samples E and F.

[0128] Next, the wire side of the paper-made base paper was subjected to corona discharge treatment, and high-density polyethylene (density 0.94 g/cm2, MI = 8.0) and low-density polyethylene (density 0 .92g/cm2, MI=.4
A 7:3 mixture of 6) and 6) was laminated by melt extrusion at a resin temperature of 330 DEG C., and the mixture was cooled while being matted with a cooling roll to form a back coating layer with a thickness of 10 .mu.m.

[0129] Subsequently, the felt surface of the base paper was subjected to corona discharge treatment, and low-density polyethylene containing 10% titanium oxide was melted and extruded at a resin temperature of 320°C to form a resin coating layer with a thickness of 10 μm. , thereby obtaining a glossy support.

[0130] Next, a coating solution for forming an image-receiving layer having the following composition was applied onto the above-mentioned four types of supports by a gravure coating method, and dried at a temperature of 130°C for 5 minutes to form an image-receiving layer with a thickness of 5 μm. An image receiving sheet for thermal transfer recording was obtained.

Coating liquid for forming image-receiving layer:
Vinyl chloride-isobutyl ether copolymer...
...9.0 parts (manufactured by BASF, Larofl
ex-MP25) Polyester modified silicone resin
・・・・・・・・・・・・・・・ 1.0 part [manufactured by Shin-Etsu Silicon Co., Ltd., X-24-8300] Methyl ethyl ketone・・・・・・・・・・・・・・・・・・・・４０．
0 copies.

Next, commercially available FJIX VideoGr
Printing was carried out using a FUJIX video graphic printer using the aphic VP-H ink sheet and the above image-receiving sheet for thermal transfer recording, and the performance was evaluated as follows. The results are shown in Table 1.

[0133] White spots: Count the number of white spots in the 76 x 97 mm printing area. Conveyance performance: Under the environmental conditions of a temperature of 25° C. and a relative humidity of 20%, the video printer described above was examined to see if there is any jam trouble caused by feeding multiple sheets during printing. Sorting performance: The handling performance after printing 10 sheets and stacking them was compared under environmental conditions of a temperature of 25° C. and a relative humidity of 20%. ×...Several pieces are stuck together. △: There is some resistance to handling. 〇...No problem.

[0134]

[Table 1]

[0135] As is clear from Table 1, if the surface resistivity value of the paper used as the inner paper of the support is 1010 Ω/□ or less, preferably 109 Ω/□ or less, white spots are significantly reduced, and the conveyance property and It can be seen that an image-receiving sheet for thermal transfer recording with good handling properties can be obtained.

[0136]

[Effect of the invention] The image-receiving sheet for thermal transfer recording of the present invention is
Since it prevents white spots during image formation due to charging, the quality of image formation is improved, and furthermore, it has good transportability and prevents sticking, making operation and handling easier.

Claims (1)

[Claims] 1. For thermal transfer recording, comprising an image-receiving layer laminated on a support formed by laminating thermoplastic resin layers on both sides of inner paper having a surface specific resistance of 1010 Ω/□ or less. Image receiving sheet.