JPH09300830A - Thermal transfer image receiving sheet and manufacture thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a thermal transfer image receiving sheet and manufacture thereof capable of preventing the occurrence of wave curls due to an absorption or discharge of moisture under prevention environments, and forming an excellent image without causing color slurring at the printing period. SOLUTION: The thermal transfer sheet includes a foundation material consisting at least of paper 1 and a receptor layer 4 on one surface of the foundation material, in which a moisture content of paper 1 is in the rage of 1.0-11.0, and a difference of the moisture content in the central part and end parts of paper 1 is made 0-2.0%. In addition, in a manufacture of a heat transfer image receiving sheet with a foundation material consisting at least of paper 1, a receptor layer 4 is formed at least one surface of a sheet-shaped matter to be a part of the foundation material and, as required, a rear surface layer 5 is formed on one surface of the sheet-shaped matter, and the sheet- shaped matter is stuck on both sides of paper 1, thereby controlling the moisture content of 1.0-11.0% and the difference of the moisture content in the central part and end parts of paper 1 into 0-2.0%.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a thermal transfer image-receiving sheet used in combination with a thermal transfer sheet and a method for producing the same, and more specifically, a thermal transfer image-receiving sheet using a pulp-based paper base material and a method for producing the same. It is about.

[0002]

2. Description of the Related Art Conventionally, various thermal transfer recording methods are known. As one of the methods, a sublimable dye is used as a coloring material, and a thermal head which generates heat according to a recording signal is used to form the coloring material. There is a sublimation transfer recording method in which an image is obtained by transferring an image to a thermal transfer image receiving sheet. At present, the sublimation transfer recording method is used as an information recording means in various fields, but since this recording method uses a sublimable dye as a color material, the gradation of the printing density can be freely adjusted, and the full-color image of the original can be adjusted. Can be reproduced. In addition, since the image formed by the dye is extremely clear and has excellent transparency, it is excellent in the reproducibility of intermediate colors and the reproducibility of gradation, and it is necessary to form a high-quality image comparable to a silver salt photographic image. Is possible.

As one of the image receiving sheets of the sublimation transfer recording system, a thermal transfer image receiving sheet using a paper mainly composed of pulp has been proposed. The image-formed product of the thermal transfer image-receiving sheet using a paper substrate mainly composed of this pulp has the same surface gloss, thickness, and other textures as compared with the usual printed matter produced by offset or gravure printing, and is not bent. It is suitable for various uses, such as being easily possible and binding and filing even if several sheets are stacked. Further, since the ordinary paper is cheaper than the plastic film or the synthetic paper, the thermal transfer image-receiving sheet can be manufactured at a low price.

The thermal transfer image-receiving sheet is formed of a foam film or a plastic film in order to improve the cushioning property, heat insulating property and smoothness of the base material so as to increase the image density and to obtain a printed product having no image unevenness. , Pasting with a paper base material is performed. As described above, the sublimation transfer recording type thermal transfer image-receiving sheet uses a two-layer base material in which paper and a foam film are bonded together, a three-layer base material in which foam films are bonded on both sides of the paper, and a paper base material. For example, there is one having an EC (extrusion coating) resin layer formed on one side, and paper is used as a part of the substrate in various forms. A receptive layer is applied to one surface of these base materials, and a resin layer such as a back surface layer is applied to the other surface and dried to form a thermal transfer image-receiving sheet.

[0005]

In the conventional method for producing a thermal transfer image-receiving sheet, first, a paper and a foamed film or the like are laminated to form a base material, and then a receiving layer, a back surface layer, etc. are formed on the base material. This is done by coating and drying the resin layer of. At that time, the paper in the base material is heated in the process of drying the resin layer, the water content of the paper is evaporated, and the paper is in a very dry state. After manufacturing, the dried paper absorbs moisture in the air, but when there is a foamed film, a resin layer, or the like on both sides of the paper, moisture is absorbed mainly from the end faces thereof. Therefore, the edge portion of the paper absorbs a large amount of water, and the water content decreases toward the inside. Such a difference in water content causes a wavy curl on the thermal transfer image-receiving sheet, which is a problem.

On the other hand, the present invention solves the above-mentioned problems, and does not cause wavy curl due to absorption or discharge of water in a storage environment, and further, a good image in which color misregistration does not occur during printing. It is an object of the present invention to provide a thermal transfer image-receiving sheet and a method for producing the same.

[0007]

In order to solve the above-mentioned problems, the present invention provides a thermal transfer image-receiving sheet in which a base material is at least paper and at least one receiving layer is provided on one side of the base material. The ratio is in the range of 1.0 to 11.0%, and the difference in water content between the central portion and the end portion of the paper is 0 to
It is characterized by being 2.0%. Further, in the method for producing a thermal transfer image-receiving sheet in which the base material is at least paper,
At least a receiving layer is formed on one surface of a sheet material that is a part of a base material, and a back layer is formed on one surface of another sheet material if necessary, and the sheet material is attached to both sides of the paper. It is characterized by adjusting the water content of the paper to 1.0 to 11.0% and adjusting the difference in the water content between the central portion and the end portion of the paper to 0 to 2.0%. Further, in the method for producing a thermal transfer image receiving sheet in which the base material is at least paper, the temperature of the produced thermal transfer image receiving sheet is 10 to 30 ° C. and the humidity is 40 to 30 ° C.
By aging at 90% for 6 hours or more, the water content of the paper is 1.0 to 11.0%, and the difference in water content between the central portion and the edge portion of the paper is 0 to 2. It is characterized by adjusting to 0%.

[0008]

The thermal transfer image-receiving sheet of the present invention has a water content within the range of 1.0 to 11.0% with respect to the paper constituting the base material, when incorporated into the constitution of the thermal transfer image-receiving sheet, Moreover, by setting the difference in water content between the central portion and the end portion of the paper to be 0 to 2.0%, the absorption or discharge of water in the paper is very small in a general storage environment. Therefore, a wavy curl does not occur, and a good image with no color misregistration during printing can be obtained. Further, in the method for producing a thermal transfer image-receiving sheet in which the base material is at least paper, at least the receiving layer is formed on one side of the sheet-like material that is a part of the base material, and if necessary, the back surface is provided on one side of the other sheet-like material. By forming a layer and sticking the sheet-like material on both sides of the paper, the water content of the paper as described above can be brought into the specified range. Further, in the method for producing a thermal transfer image receiving sheet whose base material is at least paper, the produced thermal transfer image receiving sheet is subjected to aging at a temperature of 10 to 30 ° C. and a humidity of 40 to 90% for 6 hours or more to obtain a paper. The water content of 1.0 to 11.0%, and the difference between the water content of the center and the edge of the paper is adjusted to 0 to 2.0%, and the water content of the paper as described above falls within the specified range. can do.

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the invention relating to the thermal transfer image-receiving sheet of the present invention will be described in detail below with reference to the drawings. FIG. 1 is a sectional view showing one embodiment of the thermal transfer image receiving sheet of the present invention. As shown in FIG. 1, a sheet-like foamed film 2 is attached to one surface of the paper 1,
A receiving layer 4 is provided on the surface of the foamed film 2. Further, a foam film 3 of a sheet-like material is attached to the other surface of the paper 1, and the back surface layer 5 is formed on the front surface of the foam film 3.
Is provided. Therefore, in FIG. 1, with the paper 1 in between,
Foamed film 2 on paper 1, Foamed film 3 on paper 1
A base material having a composite structure in which the above is bonded is used.

(Substrate) In the present invention, paper is used as at least a part of the substrate. Paper alone may be used as the base material, or another sheet-like material may be attached to one side or both sides of the paper to form the base material. As the paper 1 used as the base material, a paper that is usually used mainly of pulp, that is, plain paper is used. For example, fine paper, art paper, lightweight coated paper, lightly coated paper, coated paper, cast coated paper,
Examples thereof include synthetic resin or emulsion-impregnated paper, synthetic rubber latex-impregnated paper, synthetic resin internal-added paper, and the like. Among them, high-quality paper, lightweight coated paper, lightly coated paper, coated paper and the like are preferable. The coated paper or the like is obtained by coating a base paper with a mixture of calcium carbonate, talc, or the like and SBR latex or the like.

The water content of ordinary paper varies depending on the surrounding environment, but as will be described later, other sheet-like materials are stuck to the paper or a resin layer such as a receiving layer or a back surface layer is applied. As a result, the entry and exit of water from the surface of the paper is almost blocked, and the water is absorbed or discharged mainly from the end surface of the paper. This causes a difference in water content between the center and the edge of the paper. The state is shown in FIG. 2 as a perspective view as a concept.
FIG. 2 shows an example in which water is absorbed from the end portion 7, and the central portion 6 has a low water content, and the water content increases toward the outside. When the difference in water content between the central portion 6 and the end portion 7 exceeds a certain value, wavy curling occurs on the entire thermal transfer image receiving sheet. In the present invention, the water content of the end portion and the central portion of the paper is set to a numerical value in a specific range, and by eliminating the difference between the two,
Prevents the occurrence of wavy curl of the thermal transfer image-receiving sheet during storage. Specifically, the water content of the paper (the water content of all parts of the paper including the central portion and the end portions) is 1.0 to 11.
It is within the range of 0%, and the difference in water content between the central portion and the end portion is 0 to 2.0%.

Even if the difference in water content between the central portion and the edge portion is 2.0% or less, the water content of the paper is less than 1.0% or 11.
When it is more than 0%, the water content of the paper is easily affected by the surrounding environment, and the water content changes by absorbing or discharging water from the edges, and the difference between the center and the edges becomes large. , Wavy curls occur. Therefore, the water content of the paper needs to be in the range of 1.0 to 11.0%. Furthermore, since the equilibrium moisture content of pulp paper in a general environment (temperature 20 ° C., humidity 60%) is about 6.0%, 4.0
% To 8.0% is a more preferable range of the water content of the paper.
The water content of the paper has been described above, but the target paper is in the state of being used as the base material of the thermal transfer image-receiving sheet, and the sheet-like materials are stuck together, the receiving layer or the back surface of the receiving layer if necessary. It is applied in the state of a thermal transfer image-receiving sheet provided with a layer. However, the moisture content of the paper as a material before constituting the thermal transfer image-receiving sheet is preferably in the same range as in the state of the thermal transfer image-receiving sheet. With the image receiving sheet, the water content of the paper is 1.0
The water content of paper as a material is not specified as long as it is within the range of ˜11.0% and the difference in water content between the central portion and the end portion is 0 to 2.0%. Paper thickness is usually 4
The thing of 0-200 micrometers is used.

Examples of the sheet-like material to be bonded to paper include plastic films and foamed films 2 and 3. Examples of the plastic film include polypropylene film, polyethylene film, polyester film, polycarbonate film, polyethylene naphthalate film, polyether ether ketone film, polyamide film, polyether sulfone film and the like. As the foamed film, a foamed polyester film, a foamed polyolefin film, or other commonly used foamed film can be used. These foamed films, for example, are formed by mixing a film-forming resin with an inorganic or organic filler or the like into a sheet shape and subjected to uniaxial stretching or multiaxial stretching to form fine pores inside. It is a thing. Examples of the resin forming the foamed films 2 and 3 include polypropylene, polyethylene, polystyrene, polyvinyl chloride, polyester, and the like, but a foamed polyolefin film, particularly a foamed polypropylene film is preferable. Further, as the filler, titanium oxide, silicon oxide, magnesium carbonate, barium sulfate, zinc oxide,
Inorganic filler such as talc and clay, polystyrene type,
Melamine-based, acrylic-based, organic silicone-based organic fillers and the like can be used.

The thickness of such a foamed film is from 20 to
It is about 200 μm. If the thickness is less than 20 μm, the cushioning property and the heat insulating property are deteriorated, and the thickness is 200 μm.
If it is thicker, curling is likely to occur. The foamed film may be composed of a single layer, but may have a multilayer structure. Examples of multi-layer structure include foamed layer / non-foamed layer /
There is a foamed layer having a three-layer structure, but in this case, the three layers can be collectively formed into a foamed film. Further, in the case of a two-layer structure such as a foam layer / non-foam layer, if the receiving layer is formed on the foam layer side, good cushioning properties due to the foam layer are obtained.
Improves the sensitivity of the image formed on the receiving layer. Further, even when the receiving layer is formed on the non-foaming layer side, if the thickness of the non-foaming layer is such that the sensitivity of the image is not adversely affected,
It can be used without any particular problem.

Specific examples of such foamed film include commercially available synthetic paper YUPO (manufactured by Oji Yuka Synthetic Paper Co., Ltd.), Toyopearl SS (manufactured by Toyobo Co., Ltd.), pyrene film (manufactured by Toyobo Co., Ltd.), Crisper (manufactured by Toyobo Co., Ltd.), W-900 (manufactured by Diamond Wheel Hoechst Co., Ltd.), E-60 (manufactured by Toray Co., Ltd.) and the like can be mentioned. A preferable example of the base material is a paper having foamed films attached to both sides thereof. The cushioning and heat insulating properties of the foamed film improve the sensitivity of the image. Also, by sticking the both sides of the paper, the effect of preventing curling caused by heating during printing is enhanced.

In the thermal transfer image-receiving sheet of the present invention, when a composite for laminating a sheet-like material with paper is used as a base material, the adhesive for laminating the sheet-like material with the paper is dry lamination or wet. It can be appropriately selected according to the laminating method such as lamination and the method of adhering by electron beam irradiation after pasting, and is not limited. In addition, since paper is used as the base material, when the adhesive is water-based or emulsion type, water is supplied to the paper when the adhesive is applied, so that the water content of the paper must be strictly controlled. On the other hand, when using a solvent-type adhesive, it is easy to control the water content of the paper during application and easy to handle. Examples of solvent-type adhesives include vinyl acetate resins, acrylic resins, vinyl acetate-acrylic copolymer resins, vinyl acetate-vinyl chloride copolymer resins, ethylene-
Examples thereof include those containing vinyl acetate copolymer resin, polyamide resin, polyvinyl acetal resin, polyester resin, polyurethane resin and the like as components.

(Receiving layer) The receiving layer 4 provided on the substrate is
If necessary, various additives such as a release agent are added to a varnish containing a resin as a main component that easily dyes a coloring material. Resins that are easily dyed include polyolefin resins, polyvinyl chloride resins, polyvinyl acetate, polyacrylic acid esters, polyester resins, polyamide resins, ionomers, and cellulose derivatives. A simple substance, a mixture or a copolymer thereof can be used, and among them, a polyester resin and a vinyl resin are preferable. Receptive layer 4
In order to prevent heat fusion with the thermal transfer sheet during image formation, a release agent may be added. As the release agent, a silicone oil, a phosphate ester plasticizer or a fluorine compound can be used, and particularly, a silicone oil is preferably used. As silicone oil, epoxy modified, alkyl modified, amino modified, carboxyl modified,
A modified silicone oil such as alcohol-modified, fluorine-modified, alkylaralkylpolyether-modified, epoxy / polyether-modified, or polyether-modified is preferably used, and among them, a reaction product of a vinyl-modified silicone oil and a hydrogen-modified silicone oil is preferable. The amount of the release agent added is 0.2 with respect to 100 parts by weight of the resin for forming the receiving layer.
Preference is given to 30 to 30 parts by weight. The coating amount of the receiving layer is
^{0.5g / m 2 ~10g / m 2} ( solid basis, unless otherwise specified coating amount of the present invention hereinafter, a is value on solid basis) is preferred.

(Intermediate Layer) In the present invention, an intermediate layer made of various resins may be provided between the base sheet and the receiving layer. An excellent function can be added to the thermal transfer image-receiving sheet by making the intermediate layer play various roles. As an example, as a resin that imparts cushioning properties, a resin having large elastic deformation or plastic deformation, for example, a polyolefin resin, a vinyl copolymer resin, a polyurethane resin, a polyamide resin, or the like is used, and a thermal transfer image-receiving sheet is obtained. It is possible to improve the printing sensitivity of and to prevent the roughness of the image. In addition, when the intermediate layer is provided by using a resin having a glass transition temperature of 60 ° C. or higher, or a resin cured by a curing agent or the like, the sheets adhere to each other when the thermal transfer image-receiving sheets are stacked and stored. It is possible to improve the storage performance of the thermal transfer image receiving sheet, for example, by preventing it from being lost.

Further, as an intermediate layer, in order to impart an antistatic ability, a resin obtained by dissolving or dispersing an antistatic agent or a resin having an antistatic ability in a solvent is applied to the above-mentioned resins. , An intermediate layer can be formed. Examples of the antistatic agent include fatty acid esters, sulfuric acid esters, phosphoric acid esters, amides, quaternary ammonium salts, betaines, amino acids, acrylic resins, ethylene oxide adducts and the like. As the resin having the antistatic ability, for example, quaternary ammonium salt-based, phosphoric acid-based, ethosulfate-based, vinylpyrrolidone-based, sulfonic acid-based resins, etc. are added to resins such as acrylic resin, vinyl-based resin, and cellulose resin. A conductive resin in which a group having an antistatic effect is introduced or copolymerized can be used. Particularly, a cation-modified acrylic resin is preferable.

(Back Layer) Further, in a thermal transfer image-receiving sheet in which a plurality of resin layers including a receiving layer are formed on one surface of a base material such as plain paper, curling may occur depending on the humidity and temperature in the environment. In order to prevent this curl, an aqueous solution of polyvinyl alcohol, polyethylene glycol, glycerin or the like is applied as the back surface layer 5 to the surface of the base material opposite to the side where the receiving layer is provided, or a humidification treatment is performed to prevent the curl. Good to process. Further, a back surface layer 5 containing a resin may be provided on the surface of the thermal transfer image-receiving sheet opposite to the receiving layer for the purpose of imparting rigidity and lubricity. In order to impart lubricity to the back surface layer 5, a resin in which an inorganic or organic filler is dispersed in the resin of the back surface layer 5 is used. As the resin used for imparting rigidity and lubricity, a conventionally known resin or a resin obtained by blending them can be used.
Further, a lubricant such as silicone or a release agent may be added to the back surface layer 5. The coating amount of these backside layers is 0.
It is preferably about 05 g / m ^{2 to 3} g / m ² .

(Method for Producing Thermal Transfer Image Receiving Sheet) The method for producing the thermal transfer image receiving sheet of the present invention includes the following methods,
By the method, in the final thermal transfer image-receiving sheet configuration,
The water content of the paper can be in the range of 1.0 to 11.0%, and the difference in water content between the central portion and the edge portion can be 0 to 2.0%. A: Do not overheat the paper during the production of the thermal transfer image-receiving sheet. During the drying when forming the receiving layer and the backside layer, the heating is performed at 130 ° C. for about 1 minute, but if the paper is heated to this extent However, the water content inside the paper evaporates, and the water content decreases significantly. Immediately after production, no curl is observed, but when it is stored at room temperature, it gradually absorbs water from the end face of the paper and a wavy curl occurs.

Therefore, in order to prevent the paper from being subjected to a strong drying step, after the resin layer such as the receiving layer and the back surface layer is formed on the sheet-shaped material, the sheet-shaped material and the paper are bonded together.
Even when the sheet-like material and the paper are attached to each other, it is important to control the drying temperature and time, because excessive heating causes curling. For example, curling does not occur when heated at 60 ° C. for 1 minute or less. Specific bonding methods include, but are not particularly limited to, dry lamination, wet lamination, and a method of bonding by EB irradiation after bonding using EB adhesive.

As an example, a manufacturing example of the thermal transfer image-receiving sheet having the structure shown in FIG. 1 will be described. First, on one side of the foam film 3,
The back surface layer 5 is formed by coating and drying. Next, an adhesive is applied to the side of the foamed film 3 on which the back surface layer 5 is not formed, and paper is attached. On the other hand, the receptive layer 4 is applied to one surface of the foamed film 2 and dried to form the receptive layer 4. At this time, if necessary, a primer layer or an intermediate layer can be formed between the foam film 3 and the receiving layer 4. Finally, an adhesive is applied to the side of the foamed film 2 on which the receiving layer 4 is not formed, and the paper 1 and the foamed film 2 are bonded together to form a thermal transfer image-receiving sheet. In the above examples, the bonding adhesive is applied to the sheet side, but may be applied to the paper side. When coated on the paper side, the surface of the paper is smoothed by the adhesive even if a paper having a rough surface is used, and the transferred image is not adversely affected.

B: Execution of Aging After Production of Thermal Transfer Image Receiving Sheet Even if the paper is strongly dried at the time of producing the thermal transfer image receiving sheet, the water content of the paper can be adjusted within a prescribed range by aging for a certain period. it can. For example, even if a paper and a foam film are attached to each other to form a base material, a resin layer such as a receiving layer is applied to the base material, and heating is performed at 130 ° C. for 1 minute, the manufactured thermal transfer image-receiving sheet is obtained. With aging,
The water content of the paper can be adjusted. Aging conditions vary depending on the type, thickness, size, etc. of the paper used, but the temperature is 10
Aging is carried out at -30 ° C and humidity of 40-90% for 6 hours or more.

(Measurement Method of Water Content) The water content is measured by J
It is carried out by the method defined by ISP 8127-1979. The water content is calculated by the following formula. Moisture content (%) = [(mass before drying−mass after drying) / mass of test piece] × 100 First, the portion whose moisture content is to be measured is cut out and the mass of the thermal transfer image-receiving sheet is measured. Next, the thermal transfer image-receiving sheet is dried, the mass after drying is measured, and the change amount before and after drying is calculated. The change in mass of the thermal transfer image-receiving sheet before and after drying corresponds to the amount of change in the water content of the paper. Next, the mass of the paper in the thermal transfer image receiving sheet is calculated, and the moisture content of the paper can be derived from the amount of change in the mass of the thermal transfer image receiving sheet and the mass of the paper.

[0026]

EXAMPLES The present invention will be described in detail below by showing Examples and Comparative Examples. (Example 1) As a paper, New Top basis weight 72.3 g
/ M ² (manufactured by Shin-Oji Paper Co., Ltd.) was used as a sheet-shaped product, which was a foamed film Pyrene film P4256 (manufactured by Toyobo Co., Ltd., 0.63 g / cm ³ ). First,
On one side of the foamed film, a backside layer of the following composition 1.0
After applying g / m ² (weight after drying, the same applies below), an adhesive having the following composition was applied on the other surface at 4.5 g / m ² .

Back side layer Acrylic polyol resin 300 parts by weight (Dainippon Ink and Chemicals, Inc. Acridic 47-538) Isocyanate curing agent 30 parts by weight (Takeda A-14 Takenate A-14) Polyamide fine particles 1 part by weight (Kanto Paint Co., Ltd. MW-330) Catalyst (Sanko Kisei Co., Ltd. S-CAT24) 1 part by weight

Adhesive urethane resin 3 parts by weight (Takelac A-969V manufactured by Takeda Pharmaceutical Co., Ltd.) Isocyanate curing agent 1 part by weight (Takenate A-5 manufactured by Takeda Pharmaceutical Co., Ltd.) 6 parts by weight ethyl acetate

[0029] Next another one foamed film of the same type as those described above, the intermediate layer and the receptive layer of the following composition, respectively in this order ^{3.5g / m 2, 4.5g / m} 2
Coated Then, 4.5 g / m ² of the above-mentioned adhesive was applied to the surface on which the receiving layer was not formed. Intermediate layer polyurethane resin 10.0 parts by weight (Nippon Polyurethane Industry Co., Ltd. N-5199) Titanium oxide (average particle size 0.5 μm) 10.0 parts by weight Isocyanate curing agent 3.0 parts by weight (Takeda Chemical Industry Co., Ltd. Takenate A-14) Methyl ethyl ketone / toluene = 1/1 97.0 parts by weight

Receptor layer Vinyl chloride-vinyl acetate copolymer 100 parts by weight (Denki Kagaku Kogyo Co., Ltd., # 1000D) Amino-modified silicone 3 parts by weight (Shin-Etsu Chemical Co., Ltd., X-22-349) Epoxy-modified silicone 3 parts by weight (KF-393, manufactured by Shin-Etsu Chemical Co., Ltd.) Methyl ethyl ketone / toluene = 1/1 400 parts by weight

Finally, a foam film was attached to both sides of the paper by dry lamination. The heating temperature of the lamination nip roll was 60 ° C. on the roll surface. Then, the prepared thermal transfer image receiving sheet was cut into A4 size.

Example 2 A thermal transfer image-receiving sheet was prepared by using the same material as in Example 1 and changing the manufacturing process.
First, an adhesive was applied to both sides of the paper, dried at 60 ° C. for 15 seconds, and then a foamed film was attached by dry lamination to prepare a base material. The heating temperature of the lamination nip roll was 60 ° C. on the roll surface. Next, the back surface layer was formed on one surface of the substrate, and the intermediate layer and the receiving layer were formed on the other surface in this order. The coating amounts of the back surface layer, the intermediate layer and the receiving layer are the same as in Example 1. Drying was performed at 130 ° C. for 1 minute after forming each layer. Cut the created thermal transfer image-receiving sheet into A4 size and
Aging was performed at 5 ° C. and a humidity of 60% for 20 days.

(Embodiment 3) A thermal transfer image-receiving sheet was prepared by the same material and manufacturing process as in Embodiment 2, and then at a temperature of 25 ° C.
Aging was performed for 20 days at a humidity of 40%. (Example 4) After a thermal transfer image-receiving sheet was prepared by the same material and manufacturing process as in Example 2, aging was carried out at a temperature of 25 ° C and a humidity of 80% for 20 days.

(Comparative Example) A thermal transfer image-receiving sheet was prepared by using the same material and manufacturing process as in Example 2. After that, no aging was performed. (Evaluation) Moisture content of the thermal transfer image-receiving sheets of Examples and Comparative Examples, and a state of the thermal transfer image-receiving sheet after being stored at a temperature of 25 ° C. and a humidity of 80% for 3 days. With a commercially available thermal transfer printer,
Table 1 shows the results of printing on a thermal transfer sheet suitable for the printer. (Below margin)

[0035]

[Table 1]

[0036]

As described above, according to the present invention, in the method for producing a thermal transfer image-receiving sheet in which the base material is at least paper, at least the receiving layer is formed on one side of the sheet-like material which is a part of the base material. If necessary, a back layer is formed on one side of another sheet-like material and the sheet-like material is attached to both sides of the paper, or the manufactured thermal transfer image-receiving sheet has a temperature of 10 to 30 ° C. and a humidity of 40. By performing aging at 90% to 90% for 6 hours or more, the thermal transfer image-receiving sheet of the present invention has a water content of paper in the range of 1.0 to 11.0%,
Moreover, the difference in water content between the central portion and the edge portion of the paper is 0 to 2.0%. As a result, in a general storage environment, absorption or discharge of water from the paper is extremely reduced, wavy curl does not occur, and a good image without color misregistration during printing can be obtained. .

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing one embodiment of a thermal transfer image receiving sheet of the present invention.

FIG. 2 is a conceptual perspective view showing the difference in water content between the central portion and the end portion of the paper of the thermal transfer image-receiving sheet of the present invention, showing a state of absorbing water from the end portion.

[Explanation of symbols]

 1 Paper 2, 3 Foamed film 4 Receiving layer 5 Back surface layer 6 Center part 7 Edge part

Claims (3)

[Claims] 1. In a thermal transfer image-receiving sheet having a base material of at least paper and having at least a receiving layer on one surface of the base material, the water content of the paper is in the range of 1.0 to 11.0%, and The difference in water content between the central portion and the end portion of the paper is 0 to 2.
A thermal transfer image-receiving sheet characterized by being 0%. 2. A method for producing a thermal transfer image-receiving sheet in which a base material is at least paper, wherein at least a receiving layer is formed on one surface of a sheet-like material which is a part of the base material, and if necessary, another sheet-like material. By forming a back surface layer on one side and sticking the sheet-like material to both sides of the paper, the water content of the paper is 1.0 to 11.0%, and the water content of the central portion and the end portion of the paper is A method for producing a thermal transfer image-receiving sheet, characterized in that the difference in the rate is adjusted to 0 to 2.0%. 3. A method for producing a thermal transfer image receiving sheet having a base material of at least paper, wherein the produced thermal transfer image receiving sheet is aged for 6 hours or more at a temperature of 10 to 30 ° C. and a humidity of 40 to 90%. The heat transfer image-receiving sheet is characterized in that the water content of the paper is adjusted to 1.0 to 11.0% and the difference between the water content of the central portion and the water content of the edge is adjusted to 0 to 2.0%. Manufacturing method.