JPH058556A - Thermal transfer image receiving sheet - Google Patents

Abstract

PURPOSE:To obtain a thermal transfer image receiving sheet easy in bending processing or filing and having an excellent plain paper feeling by forming a dye receiving layer to the surface of a paper base material sheet having a specific range of a wt. basis if necessary through an intermediate layer. CONSTITUTION:A thermal transfer image receiving sheet is formed by providing a dye receiving layer to the surface of a paper base material sheet if necessary through an intermediate layer but, in this case, as the paper base material sheet, various papers, for example, PPC paper, thermal transfer paper, fine paper, art paper, coated paper, cast coated paper or kent paper are used and the wt. basis thereof is set to 60-120g/m<2>. Both of the whiteness and opacity of the paper base material sheet are set to about 70% and, when the surface of the paper base material sheet is lack in smoothness, said surface of the base material sheet is subjected to sealing treatment using latex. Further, antistatic treatment and/or curl preventing treatment are applied to the paper base material sheet.

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, and more specifically, it is an object of the invention to provide a thermal transfer image-receiving sheet which is easy to fold and filing and is excellent in plain paper feeling at low cost.

[0002]

2. Description of the Related Art Conventionally, various thermal transfer methods are known. Among them, a sublimable dye is used as a recording agent, and this is carried on a base material sheet such as paper or a plastic sheet to form a thermal transfer sheet. There has been proposed a method of forming various full-color images on a thermal transfer image-receiving sheet that can be dyed with a dye, for example, a thermal transfer image-receiving sheet having a dye-receiving layer on the surface of paper or a plastic film. In this case, the thermal head of the printer is used as the heating means, and a large number of three-color or four-color dots are transferred to the thermal transfer image-receiving sheet by heating for an extremely short time, and the full-color image of the original is formed by the multicolor dots. Is to be reproduced. The image formed in this way is extremely clear because the coloring material used is a dye and has excellent transparency, so the resulting image has excellent reproducibility and gradation of intermediate colors, and It is similar to the image by offset printing or gravure printing of
Moreover, it is possible to form a high quality image comparable to a full color photographic image. As the thermal transfer image-receiving sheet used in the sublimation type thermal transfer system as described above, a substrate sheet provided with a dye-receiving layer is used, but since the smoothness of the dye-receiving layer is required, Plastic films, synthetic papers or laminates thereof have been used.

[0003]

[Problems to be solved by the invention] However,
In the case of the above-mentioned conventional thermal transfer image-receiving sheet, when the printed matter is subjected to folding processing or filing, it is difficult to fold it, or it cannot be thinly folded because it repels even if it is once folded, and it is bulky when filing. It was difficult to use it for general office work. In addition, it was insufficient in terms of cost and was not suitable as a general office consumable product because it had no feeling of plain paper. Therefore, an object of the present invention is to solve the above-mentioned problems of the prior art, and to provide at low cost a thermal transfer image-receiving sheet which is easy to fold, filing and the like and is excellent in plain paper feeling.

[0004]

The above object can be achieved by the present invention described below. That is, the present invention comprises a paper base sheet and a dye receiving layer formed on the surface of the paper base sheet with an intermediate layer as necessary, and the basis weight of the paper base sheet is 60 to 60.
The thermal transfer image-receiving sheet is characterized in that it is in the range of 120 g / m ² .

[0005]

[Function] As a base sheet for the thermal transfer image-receiving sheet, the basis weight is 6
By selecting a paper in the range of 0 to 120 g / m ² , it is possible to provide a thermal transfer image-receiving sheet that is easy to fold and filing and is excellent in plain paper feeling at low cost.

[0006]

BEST MODE FOR CARRYING OUT THE INVENTION Next, the present invention will be described in more detail with reference to preferred embodiments. Examples of the paper base sheet used in the present invention include various papers such as PPC paper, thermal transfer paper, fine paper, art paper, coated paper, cast coated paper,
Paper such as ketone paper is suitable, and these base sheets are required to have a basis weight of 60 to 120 g / m ² . When the grammage is less than 60 g / m ² , the base sheet has insufficient rigidity, and the opacity is insufficient, so that the quality of the image formed is not high. Also, the basis weight is 120 g / m ^2.
If it exceeds, there is a problem that the bending property when bending and filing is insufficient and bulky. The whiteness and opacity of the paper base sheet are preferably 70% or more.

The dye receiving layer formed on the surface of the paper base sheet is for receiving the sublimable dye transferred from the thermal transfer sheet and maintaining the formed image. The method for forming the dye-receptive layer may be a coating method as in the prior art, but in this case, the surface of the base sheet may lack smoothness. It is preferable to perform the sealing treatment. The preferred method of forming the dye receiving layer is a transfer method of the receiving layer. In this case, even if the surface of the substrate sheet lacks smoothness, it is possible to form a dye receiving layer having excellent surface smoothness. I can. The method of transferring the receiving layer will be described below.

The receptive layer transfer film used in the receptive layer transfer method comprises a substrate film and a dye receptive layer releasably provided on one surface thereof. In a preferred embodiment, the surface of the receptive layer is pressure-sensitive and heat-sensitive. An adhesive layer is provided. A desired thermal transfer image-receiving sheet is obtained by stacking the above-mentioned receptive layer thermal transfer film on the above-mentioned base material sheet, applying pressure to each other by a suitable pressing means to bond them together, and then peeling off the base material film.

As the base film of the receptive layer heat transfer film used in the present invention, the same base film as that used in the conventional heat transfer film can be used as it is, and other materials can be used. There is no particular limitation. Specific examples of preferable base film include:
For example, thin paper such as glassine paper, condenser paper, paraffin paper, polyester, polypropylene, cellophane, polycarbonate, cellulose acetate, polyethylene, polyvinyl chloride, polystyrene, nylon, polyimide, polyvinylidene chloride, ionomer and the like, or these and the above papers. Examples of the base film include a composite of The thickness of the base film can be appropriately changed according to the material so that the strength and the like are appropriate.
Its thickness is preferably 3 to 100 μm.

A release layer may be formed on the surface of the substrate film prior to the formation of the receiving layer. The release layer is formed of a release agent such as wax, silicone wax, silicone resin, fluororesin, acrylic resin or the like. The forming method may be the same as the forming method of the receiving layer described later, and the thickness thereof is 0.
About 01 to 5 μm is sufficient. If a matte receiving layer is desired after transfer, it may be formed into a matte surface by incorporating various particles in the release layer or by using a base film having the release layer side surface matt treated. Of course, it is not necessary to form the release layer when the base film as described above has an appropriate releasability.

The dye receiving layer formed on the surface of the above-mentioned base film is formed by transferring the receiving layer to the base of any image receiving sheet,
Accepts sublimable dyes transferred from thermal transfer film,
This is for maintaining the formed image. Examples of the resin for forming the dye receiving layer include polyolefin resins such as polypropylene, polyvinyl chloride, vinyl chloride-vinyl acetate copolymer, halogenated polymers such as polyvinylidene chloride, polyvinyl acetate, and polyacrylic ester. Vinyl polymers such as polyethylene terephthalate,
Polyester resin such as polybutylene terephthalate,
Polystyrene resins, polyamide resins, copolymer resins of olefins such as ethylene and propylene with other vinyl monomers, ionomers, cellulose resins such as cellulose diacetate, polycarbonates, and the like,
Particularly preferred are vinyl resins and polyester resins.

Preferred releasing agents to be mixed with the above resins include silicone oils, phosphate ester type surfactants, fluorine type surfactants and the like, but silicone oils are preferable. As the silicone oil, modified silicone oil such as epoxy modified, alkyl modified, amino modified, carboxyl modified, alcohol modified, fluorine modified, alkylaralkyl polyether modified, epoxy / polyether modified or polyether modified is desirable. As the release agent, one type or two or more types are used. or,
The amount of the release agent added is preferably 0.5 to 30 parts by weight with respect to 100 parts by weight of the dye receiving layer forming resin. If the addition amount range is not satisfied, problems such as fusion of the thermal transfer film and the dye receiving layer or deterioration of printing sensitivity may occur. By adding such a releasing agent to the dye receiving layer, the releasing agent bleeds out on the surface of the receiving layer after transfer to form a releasing layer.

The receptive layer may be prepared by dissolving one of the above-mentioned base film and the resin as described above with necessary additives such as a releasing agent in an appropriate organic solvent, or by dissolving it in an organic solvent. It is formed by applying and drying the dispersion dispersed in water by a forming means such as a gravure printing method, a screen printing method, and a reverse roll coating method using a gravure plate. When forming the dye receiving layer,
Titanium oxide, zinc oxide, kaolin clay, calcium carbonate, for the purpose of improving the whiteness of the dye receiving layer to further enhance the sharpness of the transferred image and improving the foil cutting of the receiving layer.
White pigments such as fine powder silica and fillers can be added. The dye receiving layer formed as described above may have any thickness, but it is generally 1 to 50 μm thick. Further, such a dye receiving layer is preferably a continuous coating, but it may be formed as a discontinuous coating by using a resin emulsion or a resin dispersion.

Further, an intermediate layer for imparting whiteness, cushioning property, concealing property and the like can be provided on the surface of the above-mentioned receiving layer, and the transferability of these layers including the receiving layer can be improved. Therefore, it is preferable to provide a pressure-sensitive or heat-sensitive adhesive (adhesive) layer on the surface of the receiving layer or the intermediate layer. These adhesive layers are, for example, adhesives for dry laminating, such as two-component curing type polyurethane adhesives, epoxy adhesives, acrylic adhesives, etc., which are used for film lamination in the related art. Is also used, and emulsions of vinyl acetate resin and acrylic resin for wet laminating can be advantageously used. These adhesive layers are preferably formed to a thickness of about 0.5 to 30 μm. Further, by including air bubbles such as microcapsules in these adhesives, the cushioning property of the image receiving sheet obtained can be improved.

The above-mentioned paper base sheet is used as the base sheet of the image receiving sheet for transferring the receiving layer using the above-mentioned receiving layer transfer film. As a method of transferring the receiving layer to the base sheet, a usual laminator can be advantageously used as it is. Further, it is preferable that the paper base sheet or the thermal transfer image-receiving sheet obtained above is subjected to antistatic treatment or curl prevention treatment. Various antistatic agents such as cationic, nonionic or anionic surfactants can be used for antistatic treatment, and starch, casein, polyvinyl alcohol, polyacrylic acid salts, polyethylene glycol, etc. can be used for curling prevention. The water-soluble resin is preferably applied to or impregnated into the base material sheet.

[0016]

EXAMPLES Next, the present invention will be described more specifically with reference to Examples and Comparative Examples. In the text, parts and% are based on weight unless otherwise specified.

Examples 1 to 4 and Comparative Examples 1 to 2 On the surface of a matted polyester film (X-42, manufactured by Toray), a coating solution for receiving layer having the following composition was dried by a bar coater at 2.5 g / dry. It is applied at a ratio of m ² and temporarily dried with a dryer, and then dried in an oven at 100 ° C. for 30 minutes to form a dye receiving layer, and an acrylic adhesive (E-1000, manufactured by Soken Kagaku Was coated and dried at a rate of 5 g / m ² to form a pressure-sensitive adhesive layer to obtain a receptor layer transfer film used in the present invention and comparative examples. Receptor layer coating liquid composition ; vinyl chloride / vinyl acetate copolymer (1000GKT, manufactured by Denki Kagaku Kogyo) 100 parts Amino-modified silicone (X-22-343, Shin-Etsu Chemical Co., Ltd.) 3 parts Epoxy-modified silicone (KF-393) , Manufactured by Shin-Etsu Chemical Co., Ltd. 3 parts Methyl ethyl ketone / toluene (weight ratio 1/1) 500 parts The above-mentioned receptive layer transfer film is stuck to the base material sheet shown in Table 1 below by a roller, and then the polyester film is peeled off to make the present invention and A thermal transfer image receiving sheet of Comparative Example was obtained. When the whiteness (%), opacity (%), filing property and texture of the thermal transfer image-receiving sheet obtained above were examined, the results shown in Table 1 below were obtained.

[0018]

[Table 1] A: Cast coated paper (test product) B: Thermal transfer paper (TTR-PW, manufactured by Mitsubishi Paper Mills) C: PPC paper (made by Jujo Paper Mills) D: Cast coated paper (NK crystal coated, Nippon Paper Mills) E: Cast coated paper Paper (Mirror coat, Kanzaki Paper Co., Ltd.) F: Cast coated paper (Mirror coat, Kanzaki Paper Co., Ltd.)

Example 5 Instead of the base sheet used in Example 1, 0.5% of an antistatic agent (Statchide, manufactured by Analyte Chemical Co.) was used.
A thermal transfer image-receiving sheet of the present invention was obtained in the same manner as in Example 1 except that the same substrate sheet on which the solution was applied and dried was used. Example 6 Instead of the base sheet used in Example 1, the same base sheet coated with a 1% solution of polyvinyl alcohol (KL-05, manufactured by Nippon Synthetic Chemical Industry) on the back surface and dried was used, and the other operations were performed. A thermal transfer image-receiving sheet of the present invention was obtained in the same manner as in Example 1.

On the other hand, a dye layer ink having the following composition was prepared, and a 6 μm thick polyethylene terephthalate film having a heat-treated back surface was coated with a dry coating amount of 1.0 g / m ²
Coated with a wire bar and dried, and then a few drops of silicone oil (X-4414003A, made by Shin-Etsu Silicone) was dropped on the back surface with a dropper, and then spread over the entire surface and subjected to back surface treatment coating to obtain a thermal transfer film. . Ink composition for dye layer : Disperse dye (Kayaset Blue 714, manufactured by Nippon Kayaku) 4.0 parts Ethyl hydroxycellulose (manufactured by Hercules) 5.0 parts Methyl ethyl ketone / toluene (weight ratio 1/1) 80.0 parts Dioxane 10.0 copies

The above thermal transfer film was placed on the surface of the image receiving sheet of each of the image receiving sheets of Examples 5 to 6 and Comparative Examples 1 and 2, and the output was 1 W / dot and the pulse width was 0.3 to 0 by using a thermal head. .45 msec., Dot density 3 dots / mm
Printing was carried out under the conditions described above to form a cyan image. Among the color images obtained above, the images of Examples 5 and 6 were high quality images without curl and electrification, but the images of Comparative Examples 1 and 2 were severely curled and paper dust adhered due to electrification. When the paper dust adhered to the surface of the receiving layer, that portion became a color loss state.

[0022]

[Effects] According to the present invention as described above, by selecting a paper having a basis weight of 60 to 120 g / m ² as a paper base sheet of a thermal transfer image-receiving sheet, it is easy to perform bending and filing and the like. It is possible to provide a thermal transfer image-receiving sheet excellent in paper feel at low cost.

Claims (4)

[Claims] 1. A paper base sheet and a dye receiving layer formed on the surface of the paper base sheet with an intermediate layer, if necessary, and the basis weight of the paper base sheet is in the range of 60 to 120 g / m ² . A thermal transfer image-receiving sheet characterized in that 2. The thermal transfer image-receiving sheet according to claim 1, wherein the whiteness of at least one surface of the paper base sheet is 70% or more. 3. The thermal transfer image-receiving sheet according to claim 1, wherein the opacity of the paper base sheet is 70% or more. 4. The thermal transfer image-receiving sheet according to claim 1, wherein the paper base sheet is subjected to antistatic treatment and / or curl prevention treatment.