JPH07199459A - Photosensitive transfer sheet - Google Patents

Abstract

PURPOSE:To enhance workability and to obtain a pre-press color proof of higher accuracy by enhancing reflectivity through the addition of an active-ray reflecting material to a peeling layer. CONSTITUTION:A transparent, active-ray absorbing layer A-2, formed of an active ray absorber, an antistatic agent and a film-forming polymer resin, is stacked on one side of a transparent support A-1, and a transparent peeling layer B-1 to be strongly bonded to the transparent support A-1, a thermally- fusing, transparent intermediate layer B-2 that can be peeled from the peeling layer B-1, and a colored photosensitive layer C-1 are stacked on the other side of the transparent support. An active-ray reflecting material is contained in a film-forming polymer resin forming the peeling layer B-1. The active-ray reflecting material in the peeling layer B-1 is either a mica pigment subjected to a variety of surface treatments, powder aluminum, titanium oxide, zinc oxide, or barium sulfate, or a mixture of them. The sensitivity of a photosensitive layer can be controlled by varying the reflection characteristic.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a multicolor image forming material, and more specifically, to a photosensitive transfer used for obtaining a prepress color proof which can be mainly used for proofing work which is indispensable in a photomechanical process. It is about the seat.

[0002]

2. Description of the Related Art In color printing, a prepress color proof for checking the color and tone of the finish of printing has conventionally been mainly classified into an overlay method and a surprint method.

In the overlay method, each color separation original plate is used to print on a transparent support coated with a colored photosensitizer in accordance with each color, and each color is superposed on a white sheet for calibration (USP3136637, USP3221553, USP332668
2). This method can produce proofs quickly and can be used as a color separation proof by appropriately combining two or three colors. However,
This type also causes the respective transparent supports to be superposed on each other, resulting in turbidity and a sensory significant difference as compared with a printed matter printed by a printing machine or a proofing machine.

Various methods for forming a multicolor image by the surprint method have been proposed. That is, in the method using a pressure-sensitive adhesive, a colored photosensitive layer and a pressure-sensitive adhesive layer are mainly laminated on a support in this order, and the adhesive layer surface is sufficiently pressed and adhered to a white base mount to be transferred to a rear support. By peeling off the colored photosensitive layer, the colored photosensitive layer is transferred to the mount together with the adhesive layer. Thereafter, a color-separated original corresponding to the color tone of the colored photosensitive layer is contact-exposed, developed with a dedicated developer and dried to form a separated image. Further, the same operation is repeated for different colors from the above to form a multicolor image. (Japanese Patent Publication No. 47-27441)

[0005] Further, various proposals have been made for those which transfer by heat without using a pressure sensitive adhesive. For example, if an original is placed on a support provided with a colored photopolymerizable layer that exhibits tackiness at a certain temperature or higher and contact exposure is carried out, the exposed part will not exhibit tackiness, so only the unexposed part is transferred to the paper base. Things (USP3203805). Alternatively, a colored polymer layer on a support is exposed and developed, and then a colored image is thermally transferred to a base having a heat-sensitive adhesive (USP4304836). Alternatively, there is a method in which a support / release layer / colored photosensitive layer is exposed and developed to obtain a colored image, and then a heat-sensitive adhesive is applied to the adhesive surface or the image-receiving surface to perform thermal transfer (USP3721557, Japanese Examiner Sho 46
-15326 and Japanese Patent Publication No. 49-441).

The method of forming a multicolor image using the photosensitive transfer sheet of the present invention is a transparent release layer which is strongly adhered to a transparent support, and a transparent heat-fusion-bondable transparent layer which can be released from the release layer. A photosensitive transfer sheet on which an intermediate layer and a colored photosensitive layer are laminated, (1) a step in which the photosensitive material is contact-exposed with an actinic ray through a negative document, and then a non-exposed portion is subjected to a developing treatment to form an image. 2) The formed image surface is brought into close contact with the heat-sealing surface of the material to be transferred having a heat-sealing layer, heated and pressed, and then the transparent support is peeled from the intermediate layer, and the colored image is covered with the intermediate layer. It consists of processing at the stage of transferring to the transfer material.Preparing different colored tones of the colored photosensitive layer at step (1), selecting a negative document according to each tone, contact exposure and development processing. Then form the image and tint it with a particular shade of them in step (2) After transferring the image to the transfer material, (3) further bring the image surface of the photosensitive material on which a colored image having a different color tone is formed onto the transferred surface of the transfer material obtained in step (2). After heating and pressing, the transparent support is peeled off from the intermediate layer, and the colored image is transferred together with the intermediate layer onto the already transferred surface of the material to be transferred. A method for forming a multicolor image is characterized in that (3) is repeated.

This method has the advantage that the work time can be shortened because the formed images are sequentially transferred one by one onto the material to be transferred, and the exposure work of four colors can be performed simultaneously.

However, since the colored photosensitive layers of the photosensitive transfer sheet in this method have different color tones and contain colorants having different actinic ray absorption characteristics, there is a difference in sensitivity, resulting in different optimum exposure doses. was there. For example, a black photosensitive transfer sheet is significantly inferior in sensitivity to a photosensitive transfer sheet having another color tone due to the absorption characteristics of active rays by a black pigment, and in order to obtain an image strength equivalent to other colors, More exposure was needed. Therefore, the advantage that the simultaneous exposure processing of four colors is possible cannot be fully utilized.

[0009]

SUMMARY OF THE INVENTION According to the present invention, in the above-described method for forming a multicolor image, the sensitivities of the respective color photosensitive layers containing colorants having different color tones and different actinic ray absorption characteristics are made uniform to improve workability. And to provide a multicolor image forming material for obtaining a more accurate prepress color proof.

[0010]

DISCLOSURE OF THE INVENTION The inventors of the present invention have found that the photosensitive speed of a colored photosensitive layer is increased by adding an actinic ray-reflecting substance to the release layer to increase the reflectance. That is, it has been found that the sensitivity of the photosensitive layer can be controlled by reflecting the active rays that have passed through the colored photosensitive layer (active rays not used in the reaction) on the release layer and changing the reflection characteristics.

That is, a transparent actinic ray absorbing layer composed of an actinic ray absorber, an antistatic agent, and a film-forming polymer resin is adhered to one side of the transparent support, and strongly adhered to the transparent support on a different side. A transparent release layer, a heat-meltable transparent intermediate layer that can be peeled from the release layer, and a photosensitive transfer sheet of the present invention in which a colored photosensitive layer is laminated, (1) the photosensitive material through a negative document After contact exposure with actinic rays, the non-exposed area is developed to form an image, (2) the formed image surface is brought into close contact with the heat-sealing surface of the transfer material having a heat-sealing layer. After heating and pressing, the transparent support is peeled off from the intermediate layer, and the step of transferring the colored image together with the intermediate layer to the material to be transferred is performed, and the color tone of the colored photosensitive layer is changed in step (1). Prepare different ones and select a negative document according to each color tone , Contact exposure, is developed,
After forming an image and transferring a colored image having a specific color tone among them to the transfer material in step (2), (3) the image surface of the photosensitive material on which a colored image having a color tone different from the above is formed. To the already transferred surface of the transferred material obtained in step (2),
After heating and pressing, peel off the transparent support from the intermediate layer,
The step of transferring the colored image together with the intermediate layer onto the already transferred surface of the material to be transferred,
In forming a multicolor image characterized by repeating step (3), the release layer of the photosensitive transfer sheet contains an actinic ray-reflecting substance.

The present invention will be described in more detail below. The transparent support used in the photosensitive transfer sheet of the present invention,
Plastic films such as polyethylene terephthalate, polypropylene, polyethylene, polyvinyl chloride, polystyrene, polycarbonate, and triacetate are suitable. Among them, biaxially stretched polyethylene terephthalate film is preferable because of its excellent strength, heat resistance, dimensional stability, and the like. . The thickness of the support is not particularly limited, but about 50 to 150 μm is suitable.

The actinic ray absorbing layer used in the photosensitive transfer sheet of the present invention comprises a film-forming polymer, and further contains a salicylate-based, benzophenone-based or benzotriazole-based UV absorber in order to prevent halation. Has been added. And from the viewpoint of handling, conductive resin,
An antistatic agent such as conductive powder is also added. Further, in order to prevent blocking, a pigment may be added to make the surface matte. This prevents light passing through the peeling layer from causing halation and affecting the colored photosensitive layer to thicken the dot gain.

The release layer used in the photosensitive transfer sheet of the present invention is made of any one of urethane resin, melamine resin, fluororesin, silicone resin, polyester, polyolefin or a mixture thereof, and the coating thickness is 1 to 10 μm.
m, more preferably 1 to 5 μm. Further, by adding a pigment to the release layer to form a mat, the peel strength between the release layer and the intermediate layer coated thereon can be stabilized. Further, a matting pattern is also formed on the intermediate layer and the colored photosensitive layer provided on the intermediate layer, so that air can be smoothly released between the original and the colored photosensitive layer at the time of depressurizing the exposure to improve the adhesion between them. It is also possible.

In addition, blocking resistance and slipperiness on the intermediate image-receiving sheet are improved, and air is easily released between the image-receiving sheet and the intermediate layer during transfer to the intermediate image-receiving sheet by heating and pressing. Adhesion can be improved. It is possible to control the sensitivity of the colored photosensitive layer by adjusting the reflection characteristic of the actinic ray by selecting the kind of the added pigment, the particle size and the addition amount.

Pigments used for such purposes include surface-treated mica-based pigments, powdered aluminum, inorganic fine particles such as titanium oxide, zinc oxide, barium sulfate, silicon dioxide, calcium carbonate, and alumina. There are plastic powders such as polyethylene, polypropylene, polyethylene terephthalate, polystyrene, polycarbonate, acrylic ester resins, methacrylic acid resins, polyacrylonitrile and copolymers of acrylonitrile, and fine powders such as starch and cellulose. Surface-treated mica-based pigments, powdered aluminum, titanium oxide, zinc oxide and barium sulphate are particularly suitable for increasing the sensitivity of the colored photosensitive layer. 15% or more, more preferably 20% or more is desirable. The size of the pigment is 0.01 to 20 μm, more preferably 1 to
10 μm is suitable, and the sensitivity of the photosensitive transfer sheet of each color tone can be made uniform by preparing a release layer corresponding to the colored photosensitive layer of each color tone.

The intermediate layer used in the photosensitive transfer sheet of the present invention is insoluble in water, does not impair hue and transparency, is non-adhesive at room temperature, becomes tacky and fusible by heat, and has room temperature. In the case of a colored photosensitive layer which can be easily peeled from the release layer and which is insolubilized by light applied on the release layer, it has sufficient adhesion, especially after photoinsolubilization, and also has sufficient adhesion with the transfer sheet. Selected from substances having

For example, the following film-forming polymer substances can be used. Polyacrylic acid ester and acrylic acid ester copolymer, polymethacrylic acid ester and methacrylic acid ester copolymer, polyacrylic amide and acrylic amide copolymer, polyvinyl acetate and vinyl acetate copolymer, polyvinyl chloride and Vinyl chloride copolymer, polyvinylidene chloride and vinylidene chloride copolymer, polystyrene and styrene copolymer, ethylene and vinyl acetate, ethylene and acrylic ester, ethylene and vinyl chloride such as ethylene and acrylic acid, ethylene copolymer, Polyvinyl acetal resins such as polyvinyl butyral and polyvinyl formal, polyester resins, polyamide resins such as nylon and copolymerized nylon, various rubbers such as synthetic rubber and chlorinated rubber, and polys such as polyethylene and polypropylene. Olefins, cellulose derivatives, shellac, various waxes.

In addition, a mixture of these polymer substances with each other or a mixture system with other substance such as other polymer substance or plasticizer can be used. For example, even if it exhibits tackiness at room temperature, in combination with another substance capable of preventing the tackiness, or if it does not exhibit tackiness even when heated, it may be used as a tackifier, a plasticizer or the like. Combinations are also conceivable, and not only single substances but also various combinations may be considered depending on the kind of support and the like, and therefore the substances are not necessarily limited to the above substances.

For laminating the intermediate layer on the release layer coated on the support, the solution of the above-mentioned polymer substance is applied onto the release layer by a usual method and dried, or the solid polymer described above is applied. The substance may be heat-melted and applied (hot melt coating), or a film made of the above-described polymer substance may be laminated. The thickness of the intermediate layer is preferably 0.5 to 10 μm, more preferably 0.5 to 3 μm.

Used in the photosensitive transfer sheet of the present invention,
As the colored photosensitive layer which is soluble in water and insoluble by light, a conventionally known photosensitive resin can be used, and examples of the negative type are as follows. (1) A composition comprising a photosensitive ferric salt that gives ferrous ions by light, such as ferric ammonium nitrate and ferric ammonium oxalate, and a hydrophilic resin such as gelatin or polyvinyl alcohol. (2) Water-soluble resins such as gelatin, fish glue, gum arabic, polyvinyl alcohol, polyacrylamide, carboxymethyl cellulose and hydroxymethyl cellulose, and tetrazonium salts of diamino compounds such as p-aminodiphenylamine, benzidine, dianisidine and toluisodin, or p- A composition comprising a diazo compound obtained by condensation of diazophenylamine and paraformaldehyde and a diazo resin obtained by condensation of paraformaldehyde. (3) A composition comprising a diazo compound such as p-diazodiphenylamine and a diazo resin obtained by condensing paraformaldehyde. (4) 4,4'-diazidostillylbenzene, 2,2'-
A composition comprising an azide compound such as sodium disulfonate and a water-soluble resin such as polyacrylamide, polyvinyl alcohol, polyvinylpyrrolidone and gelatin. (5) 4,4'-diazidostillylbenzene, 4,4'-
A composition comprising an azide compound such as diazide chalcone and a cyclized rubber. (6) A composition comprising a cinnamic ester ester of polyvinyl alcohol, an allyl acrylic ester, and a sensitizer such as 5-nitroacenaphthene and 1,2-benzanthraquinone. (7) A composition comprising a vinyl monomer such as acrylamide and acrylic acid, a cellulose derivative and a polyvinyl alcohol derivative, and a photopolymerization initiator. (8) A composition comprising acrylamides such as methylenebisacrylamide and N, N'-hexamethylenebismethacrylamide, an alcohol-soluble nylon and a photopolymerization initiator. (9) A composition comprising an ethylenically unsaturated monomer such as acrylamide and acrylic acid, a photosensitive ferric salt such as ferric ammonium citrate, and a hydrophilic resin. (10) A modified polyvinyl alcohol composition in which a photosensitive group such as a stilvinylium group, a stilbazolium group, or a stilquinolium group is added to polyvinyl alcohol.

As an example of the positive type, naphthoquinone-
There is a composition of a quinonediazide compound such as (1.2) -diazide sulfonic acid ester and an alkali-soluble phenol formaldehyde resin. The above-mentioned photosensitive resin is a typical example, and the present invention is not limited to these.

As the colorant, a pigment dispersible in water,
A wide range of dyes such as water or alcohol-soluble dyes can be selected, but it is necessary that the dye has good miscibility with the above water-soluble polymer substance, photoinsolubilizer, and modified polyvinyl alcohol and does not adversely affect photosensitivity and developability. The color tones are basically four colors of cyan, magenta, yellow, and black in the case of color proofing in photoengraving, and it is naturally desired that each color be close to that of the printing ink. The addition amount of the colorant depends on the type and the application amount of the colored photosensitive layer, but should be determined by the desired optical reflection density of the colored image after the formed image is transferred to the transfer material.

In addition to the above, a stabilizing agent for preventing a dark reaction or a leveling agent for improving the coatability of the colored photosensitive layer which is insolubilized by light when the colored photosensitive layer is provided on the release layer surface, An antifoaming agent, a surfactant, etc. can be added as necessary. Further, in providing the colored photosensitive layer, the above components are mainly dissolved or decomposed in water and mixed, but for the purpose of defoaming or improving coatability, a water-soluble organic solvent such as alcohols may be added if necessary. It can also be partially used as a diluent.

The thickness of the colored photosensitive layer is preferably as thin as possible from the viewpoint of resolution such as halftone reproducibility, but 0.5 to 5 μm, more preferably 1 to 3 μm is suitable in view of the image density of the colorant. There is. The coating of the colored photosensitive layer on the release surface is not particularly limited as long as there is no pinhole or the like and a uniform coating film can be obtained by any conventionally known method.

Next, the transferred material used in the present invention will be described. Examples of the support include paper, plastic film, paper / plastic composite material, glass plate, metal plate and the like. The substance used for the heat-sealing layer that is intimately laminated on the support is a substance that is tacky at room temperature and shows tackiness and fusion property by heat, more specifically, an intermediate layer of a photosensitive transfer sheet. A material that can be mutually fused with the colored photosensitive layer after exposure and development should be selected. Examples of these substances are selected from the same substances as those used for the intermediate layer of the photosensitive transfer sheet, but in this case, the mutual fusion property between the intermediate layer and the colored photosensitive layer was mainly considered. In addition, not only a single substance, but a wide range of mixed systems are selected. In applying the heat-sealing layer to the support of the image-receiving sheet, a solution of the above-mentioned polymer substance is applied onto the support by a conventional method and dried, or the solid polymer substance is applied. Whether to heat-melt and apply (hot-melt coating)
Furthermore, you may laminate the film which consists of the said polymeric substance. The thickness of the heat-sealing layer depends on the resin used, but is preferably 3 to 15 μm.

As shown in FIG. 1, the transfer sheet of the present invention is first contact-exposed with an actinic ray through a film that has been subjected to a net decomposition for each separation color obtained in the photomechanical process and then exposed.
An image is formed by development processing (step 1). By selecting the photosensitive transfer sheet of the present invention corresponding to each separated color (from the film corresponding to the cyan plate, the image is closely adhered and reversed to the photosensitive transfer sheet of the present invention colored in cyan), and each colored image is provided. A photosensitive transfer sheet is obtained. Here, the intermediate layer B-2 is exposed in the non-image portion of the photosensitive transfer sheet. (Although the heat-fusion layer E of the transfer material of the image-receiving sheet is also heat-fused with the colored photosensitive layer (image portion) C-1 after image formation, this alone is not complete, and the heat exposed to the non-image portion is not sufficient. By the mutual fusion with the fusion-bondable intermediate layer B-2, the heat transfer is more complete.)

Next, the image surface of the photosensitive transfer sheet is brought into close contact with the transfer surface (surface having a heat fusion layer) of the transfer material, and heated and pressed to form an intermediate layer (unexposed portion) of the photosensitive transfer sheet. , Non-image area) B-2 and the heat-sealing layer E of the transferred material cause mutual fusion (the photo-insolubilized portion of the coloring layer, that is, the image area also fuses with the heat-sealing layer of the transferred material. Since one side is not heat-fusible, it cannot be bonded as strongly as in the non-image area.) Thereafter, when the support A of the photosensitive transfer sheet is peeled off together with the peeling layer B-1, the color-separated image shows an intermediate layer B. -2, it is easily and strongly transferred onto the transferred material (step 2).

Further, the colored image of the second color is thermally transferred onto the transferred image. In this case, the thermally fused intermediate layer (the first color of the first color is formed on the surface after the transfer of the first color. Middle layer B
-2) allows easy and strong transfer as in the first color (step 3). With respect to the third and subsequent colors, different colored images can be easily transferred together with the intermediate layer B-2 with the same result as the second color, and finally, a multicolor image can be formed on the transferred material (step 4). . By selecting a color tone (basically cyan, magenta, yellow, black) and density of each of the colored images obtained by the present invention which are close to those of the printing ink, a multicolor image very similar to the final printed matter can be obtained. , Can be used for color proofing similar to proofs.

As is clear from the above description, in this method, the formed images are sequentially transferred one by one onto the material to be transferred, so that the photosensitive transfer sheet of each color such as cyan, magenta, yellow and black is transferred. Since the exposure work can be performed at the same time, it has excellent workability. However, if the optimal exposure amount differs due to the difference in sensitivity of each color, this advantage cannot be fully utilized. The present invention makes it possible to control the sensitivity of the colored photosensitive layer by the reflection characteristics of the release layer, and the fact that the exposure work of each color can be performed simultaneously with the optimum exposure amount of each color contributes to the improvement of the workability of the printing plate making process. There are extremely large things to do.

[0031]

EXAMPLES In order to further clarify the present invention, the following examples are shown, but the present invention is not limited thereto. All "parts" in the examples indicate parts by weight.

(Example 1) <Actinic ray absorption amount forming liquid> Saftomer STH-87 65 parts (acrylic conductive polymer: Mitsubishi Yuka Co., Ltd.) Tesfan 322 31 parts (acrylamide copolymer: Hitachi Chemical Polymer ( Co., Ltd.) Thermolac F1 19 parts (Polyester: Soken Chemical Industry Co., Ltd.) Dryer 900 1.9 parts (paratoluene sulfonic acid: Hitachi Chemical Polymers) Tinuvin-109 3 parts (benzotriazole-based UV absorber: Ciba Geigy Co., Ltd.) Syloid 308 1.9 parts (Silica: Mizusawa Chemical Co., Ltd.) Toluene 100 parts Methyl ethyl ketone 100 parts Ethyl cellosolve 48 parts

<Release Layer Forming Solution-1> Tesfine 322 5 parts (acrylamide copolymer: Hitachi Chemical Polymer Co., Ltd.) Dryer 900 0.6 parts (paratoluene sulfonic acid: Hitachi Chemical Polymer Co., Ltd.) Luron Qu-628 100 parts (Vinyl chloride-vinyl propionate copolymer: Tosoh Corp.) Mizuka Seal SK-7 0.8 parts (Silica: Mizusawa Chemical Co., Ltd.) Toluene 67 parts Methyl ethyl ketone 67 parts Cyclohexanone 33 parts

<Release Layer Forming Liquid-2> TESFIINE 322 5 parts (acrylamide copolymer: Hitachi Chemical Polymer Co., Ltd.) Dryer 900 0.6 parts (paratoluene sulfonic acid: Hitachi Chemical Polymer Co., Ltd.) Luron Qu-628 100 parts (vinyl chloride-vinyl propionate copolymer: Tosoh Corporation) IRIODIN-111 17 parts (Mica-based pigment: Merck Japan Co., Ltd.) Toluene 36 parts Methyl ethyl ketone 36 parts Cyclohexanone 18 parts

<Intermediate Layer Forming Liquid> Bayronal MD-1100 91 parts (Polyester: Toyobo Co., Ltd.) Bayronal MD-1400 78 parts (Polyester: Toyobo Co., Ltd.) Water 100 parts Isopropyl alcohol 67 parts Butyl cellosolve 33 parts Dimethylformamide 22 copies

<Colored photosensitive layer forming liquid> Black liquid SBQ-modified PVA 10% aqueous solution 100 parts (N-methylstilbazolium group 1.25 mol% introduction, average polymerization degree 1700, saponification degree 88%) Pigment dispersion liquid 4 parts ( Carbon black 20% water dispersion) Water 100 parts Isopropyl alcohol 10 parts

Phthalocyanine blue, permanent carmine FB and permanent yellow HR were used in place of the above carbon black to prepare similarly colored photosensitive layer liquids for cyan, magenta and yellow. However, the yellow, cyan, magenta, and black pigment dispersions were obtained by dispersing the pigment in the following composition for 3 hours with an ink kneader. 20 parts of non-ionic surfactant 1 part (mainly polyethylene glycol alkyl phenyl ether) 80 parts of water

Biaxially stretched thickness of actinic ray absorbing layer forming liquid
One side of a 100 μm polyethylene terephthalate film was coated with a roll coater and dried at 140 ° C. for 1 minute to form an actinic ray absorption layer of about 3 μm.

Next, the release layer forming liquid-1 was applied to the surface different from the actinic ray absorbing layer by a roll coater and dried at 140 ° C. for 1 minute to form a release layer of about 3 μm. Measure the reflectance of the obtained release layer (Hitachi 320 Spectrophotometer, 150
When used with a φ integrating sphere accessory, it showed a total reflectance of 8% (360 nm). The intermediate layer forming liquid is applied onto this release layer with a roll coater and dried at 110 ° C for 1 minute to give a coating amount of about 1
A μm intermediate layer was formed. Further, a yellow liquid of a colored photosensitive layer forming liquid was applied thereon by a roll coater and dried to form a colored photosensitive layer having a coating amount of about 2 μm to obtain a yellow photosensitive transfer sheet. Similarly, for magenta and cyan, a colored photosensitive layer (coating amount: about 2 μm) was formed to obtain a photosensitive transfer sheet.

Separately from this, the release layer forming liquid-2 was applied to the opposite surface of the actinic ray absorbing layer by a roll coater and dried at 140 ° C. for 1 minute to form a release layer of about 3 μm. Similarly, when the reflectance was measured, a total reflectance of 35% (360 nm) was obtained. An intermediate layer forming liquid was applied onto the release layer with a roll coater and dried at 110 ° C. for 1 minute to form an intermediate layer having a coating amount of about 1 μm. Further, the black liquid of the colored photosensitive layer forming liquid is coated on this with a roll coater and dried to obtain a coating amount of about 2 μm.
The colored photosensitive layer of 1 was formed to obtain a black photosensitive transfer sheet.

The color separation negative film for black (sumi) plate was brought into close contact with the colored photosensitive surface of the black photosensitive transfer sheet thus prepared, and 1 m with a high pressure mercury lamp of 2 KW.
Exposure for 15 seconds from the distance of 1kg /
It was washed away with water at room temperature ejected from a nozzle pressurized to cm ² , washed with water, dried with warm air at about 50 ° C., and a negative-positive image colored black was obtained. Similarly, cyan, magenta,
For yellow, the corresponding color-separated halftone negative films were used, and the same operations as above were carried out to obtain negative-positive images colored in cyan, magenta and yellow. In each case, excellent halftone dot reproducibility equivalent to each color tone was obtained with the same exposure amount of 15 seconds.

Further, using a coated paper having a basis weight of 129.7 g / m ² as a support, a toluene / ethyl acetate solution of a copolymer of vinyl chloride and vinylidene chloride was applied to one surface of the support, dried and heated to a thickness of 6 μm. A fused layer was formed to obtain a material to be transferred.
The image surface of the black photosensitive transfer sheet having the positive image is overlaid on the heat-fusion layer surface of the material to be transferred, pressed by a roller heated to 100 ° C., and then the support of the photosensitive transfer sheet is peeled off. When peeled from between the intermediate layer and the intermediate layer, the colored image was easily transferred together with the intermediate layer onto the transfer surface of the transfer material. The adhesion at the time of transfer was good. Then, the cyan, magenta, and yellow images were sequentially heat-transferred onto the black image transferred on the transfer material by the same operation to obtain a multicolor image of four colors on the coated paper.
This was a high precision prepress color proof that closely resembled the final print.

(Example 2) Release layer forming liquid of Example-1-2
The same procedure as in Example 1 was carried out except that the amount of the pearl pigment added was changed as follows.

<Release Layer Forming Liquid-2> Tesfine 322 5 parts (acrylamide copolymer: Hitachi Chemical Polymer Co., Ltd.) Dryer 900 0.6 parts (paratoluene sulfonic acid: Hitachi Chemical Polymer Co., Ltd.) Luron Qu-628 100 parts (vinyl chloride-vinyl propionate copolymer: Tosoh Corp.) IRIODIN-111 10 parts (Pearl pigment: Merck Japan Ltd.) Toluene 36 parts Methyl ethyl ketone 36 parts Cyclohexanone 18 parts

When the above-mentioned release layer forming liquid-2 was used for the black photosensitive transfer sheet in the same manner as in Example 1, the total release rate of the obtained release layer was 22% (360 nm), and the same exposure amount of 20 seconds was used. In this way, halftone dot reproducibility equivalent to each color tone was obtained. The multicolor image formed on the transferred material was a highly accurate prepress color proof that closely resembled the final print.

When the above release layer forming liquid-2 was used in the same manner as in Example 1 for the photosensitive transfer sheet for black, the total release rate of the obtained release layer was 22% (360 nm) and the same exposure amount of 20 seconds was used. In this way, halftone dot reproducibility equivalent to each color tone was obtained. The multicolor image formed on the transferred material was a highly accurate prepress color proof that closely resembled the final print.

Example 3 Release Layer Forming Solution-2 of Example 1
The same procedure as in Example 1 was carried out except that the pigment in Example 1 was changed as follows.

<Release Layer Forming Liquid-2> Tesfine 322 5 parts (acrylamide copolymer: Hitachi Chemical Polymer Co., Ltd.) Dryer 900 0.6 parts (paratoluene sulfonic acid: Hitachi Chemical Polymer Co., Ltd.) Luron Qu-628 100 parts (Vinyl chloride-vinyl propionate copolymer: Tosoh Corp.) FA-55W 30 parts (Titanium oxide: Furukawa Machinery Co., Ltd.) Toluene 36 parts Methyl ethyl ketone 36 parts Cyclohexanone 18 parts

When the above-mentioned release layer forming liquid-2 was used for the photosensitive transfer sheet for black in the same manner as in Example 1, the total release rate of the obtained release layer was 20% (360 nm) and the same exposure amount for 20 seconds. In this way, halftone dot reproducibility equivalent to each color tone was obtained. The multicolor image formed on the transferred material was a highly accurate prepress color proof that closely resembled the final print.

Comparative Example 1 Release Layer Forming Solution-1 of Example 1
Was carried out in the same manner as in Example 1 except that was used for the photosensitive transfer sheets of all tones of black, cyan, magenta, and yellow, and halftone dot reproducibility equivalent to each tone was obtained with the same exposure amount of 15 seconds. I couldn't.

The above results are summarized in Tables 1 and 2.
By using the photosensitive transfer sheet having the total reflectance (%) of the peeling layer shown in Table 2, a dot reproducible exposure amount (second) having the characteristics shown in Table 1 was obtained. As can be seen from Table 1, Examples 1 to 3 have exposure amounts common to black, cyan, magenta, and yellow, whereas Comparative Example 1 does not have exposure amounts common to each color.

[0052]

[Table 1]

[0053]

[Table 2]

[0054]

In the photosensitive transfer sheet of the present invention, an actinic ray-reflecting substance is added to the peeling layer to adjust the reflection characteristics, thereby making it possible to control the sensitivity of the colored photosensitive layer. As a result, the sensitivities of the photosensitive transfer sheets of the respective color tones can be made uniform, the workability is improved, and a more stable and highly accurate prepress color proof can be obtained.

[Brief description of drawings]

FIG. 1 shows a step-by-step schematic representation of the method of the invention.

[Explanation of symbols]

A-1 Transparent support of photosensitive transfer sheet A-2 Actinic ray absorbing layer of photosensitive transfer sheet B-1 Release layer of photosensitive transfer sheet B-2 Intermediate layers of photosensitive transfer sheet C-1 to C-4 Each colored image of the photosensitive transfer sheet after exposure / development D Support of transfer material E Thermal fusion layer of transfer material

Claims (6)

[Claims] 1. A transparent active ray absorbing layer comprising an actinic ray absorber, an antistatic agent, and a film-forming polymer resin on one side of a transparent support, and strongly adheres to the transparent support on a different side. In the photosensitive transfer sheet in which the transparent release layer, the heat-sealable transparent intermediate layer that can be released from the release layer, and the colored photosensitive layer are laminated, a coating film-forming polymer resin that forms the release layer A photosensitive transfer sheet, which contains an actinic ray-reflecting substance therein. 2. The actinic ray-reflecting substance in the release layer is any one of mica-based pigments, powdered aluminum, titanium oxide, zinc oxide and barium sulfate, which have been subjected to various surface treatments,
Alternatively, the photosensitive transfer sheet according to claim 1, which is a mixture thereof. 3. The actinic ray (360 nm) total reflectance of the release layer is 15
% Or more, The photosensitive transfer sheet according to claim 1 or 2, wherein 4. The coating film-forming polymer resin of the release layer is any one of urethane resin, melamine resin, fluororesin, silicone resin, polyester and polyolefin, or a mixture thereof. The photosensitive transfer sheet according to any one of 1. 5. The photosensitive transfer sheet according to claim 1, wherein the intermediate layer is any one of polyester, ethylene-vinyl acetate copolymer, acrylic compound, or a mixture thereof. . 6. The colored photosensitive layer has the following general formula (I) or (II): (However, in the above formula, R ₁ and R ₂ are each independently,
Represents a hydrogen atom or an alkyl group, Y ⁻ represents a conjugated chlorinated ion of an acid, m represents an integer of 1 to 6, and n represents 0 or 1). The photosensitive transfer sheet according to any one of claims 1 to 5, wherein