JPH06324480A - Image forming material - Google Patents

Abstract

(57) [Summary] [Object] An object of the present invention is to provide an image forming material having excellent storage stability and capable of obtaining a transfer material similar to a printed material. [Structure] A photosensitive layer containing a colorant is formed on a support, and a protective film is further provided on the photosensitive layer. Imagewise exposure is performed to transfer exposed and unexposed areas of the photosensitive layer. Due to the difference in tackiness in the above, in the image forming material for transferring an image to an image receptor such as paper, the photosensitive layer contains a silicone compound modified at both terminal alcohols as a solid content of 1 to 30% by weight of the colorant. Characteristic image forming material. [Effect] The image forming material of the present invention has a low surface tension on the surface of the photosensitive layer and does not cause blocking due to heat and storage over time. In addition, the transfer of the image forming material for the second and subsequent colors is not hindered. Therefore, by using the image forming material of the present invention, it is possible to obtain a high-quality transfer material having a texture that is completely the same as that of an ordinary printed material.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image forming material. More specifically, it is an image-forming material by superposing a single color or multiple colors by utilizing the difference in adhesiveness between the exposed and unexposed areas of the photosensitive layer, and obtains a transfer similar to a print as a prepress proof for color proofing. The present invention relates to an image forming material that can be used.

[0002]

2. Description of the Related Art Conventionally, it is known in the field of printing industry to use a prepress proof as a means for confirming the finish, color tone and the like of a finally printed printed matter before printing. This prepress proof has an overlay method and a surprint method, and is properly used depending on the image quality finally obtained and the purpose of use in plate making and printing processes. In the overlay method, a transparent base film is provided with a photosensitive layer containing a color material corresponding to a color separation mask, the film and the mask are brought into close contact with each other, exposed, and developed, and the respective films are superposed. And calibrate.

Unlike the overlay method, the surprint method has a high utility value because it can obtain a hard copy. For example, as disclosed in US Pat. Nos. 3060023, 3060024 and 3060025. In this method, a photopolymer photosensitive layer consisting of several layers is laminated on a single support to sequentially form color separation images. In addition, JP-A-59-97410,
There is also a prepress proof as described in JP-A-61-1885377, which can be used in both the overlay method and the surprint method. This method is used when you want to check simple characters etc. according to the purpose of use.
The versatility is great in that if you want to obtain a hard copy for checking a subtle color portion such as a picture by checking only with the valley, you can transfer this to the transfer target. However, there is a drawback that the working environment is deteriorated because a developing process using an organic solvent is required.

On the other hand, the inventors of the present invention formed a photosensitive layer containing a dye and / or a pigment on a transparent support, and exposed the image to give a tackiness in transferring exposed and unexposed areas of the photosensitive layer. The prepress pull obtained by transferring the image to the image receptor by cohesive failure of the photosensitive layer between the roll nips using an image forming material that transfers the image to the image receptor such as paper. Unlike conventional prepress proofs, there is no layer such as an adhesive layer between the material to be printed and the image forming material, so that the image and texture very similar to the actual printed matter can be reproduced. Have already found.

These image-forming materials are usually composed of a transparent support, a photosensitive layer containing a dye and / or a pigment, and a protective film. When the image forming material is used, the transparent support and the image surface of the mask original plate are brought into close contact with each other, and image exposure is performed from the mask side.
Then, the protective film is removed, and the photosensitive layer and the image receptor are transferred while applying heat and pressure between the nip rolls. However, when the protective film is peeled off from the photosensitive layer after imagewise exposure to cause a difference in tackiness between the exposed and unexposed areas of the photosensitive layer, the preheated image receptor is removed. The image forming material receives heat due to the radiant radiation, causing a part of the unexposed portion of the photosensitive layer to be transferred to the protective film, so-called blocking occurs, so that part of the unexposed portion that should be transferred is not transferred. ， In some cases, it may not be possible to faithfully reproduce the image as the original.

In order to prevent blocking by heat, it is important that the surface tension of the photosensitive layer does not change with heat. It is well known that a silicone compound or a low-molecular wax is generally added to lower the surface tension. When a silicone compound or wax is blended in the photosensitive layer, it partially floats on the surface, so blocking can be prevented. However,
When an ordinary unmodified silicone compound such as polydimethylsiloxane is used, the silicone compound migrates from the photosensitive layer to the protective film due to storage over time, so that the antiblocking effect is significantly reduced. Further, if the blending amount of the silicone compound is increased to such an extent that blocking is not a problem, the photosensitive layer of the next color cannot be transferred because the surface tension of the transfer surface is too low.

[0007]

Therefore, as a result of intensive studies to solve the above problems, the present inventors have found that the photosensitive layer contains a silicone compound modified at both terminals with alcohol to prevent blocking due to heat, Moreover, they have found that the blocking prevention effect is prevented from lowering over time, and have completed the present invention.

[0008]

According to the present invention, a photosensitive layer containing a colorant is formed on a support, and a protective film is further provided on the photosensitive layer. In an image-forming material that transfers an image to an image receptor such as paper due to a difference in adhesiveness between the exposed and unexposed areas of the layer, the photosensitive layer contains a silicone compound modified at both terminals as a solid content as a colorant. An image forming material containing 1 to 30% by weight of

As the support, a material which is stable to heat, chemicals, light and the like and which sufficiently transmits actinic rays is preferable. For example, cellulose acetate, polystyrene, polyvinyl chloride, polyethylene terephthalate,
Examples of the film or sheet include polyethylene naphthalate, and polyethylene terephthalate is particularly preferable in terms of transparency, thermal stability, dimensional stability, and the like.

The photosensitive layer is composed of a silicone compound modified with alcohol at both ends and (a) a photopolymerizable compound and a coloring agent (b) a photopolymerizable compound, a thermoplastic resin and a coloring agent, etc., and has a thickness of 1 to 5 μm. Although it is a sunflower layer, a photopolymerization initiator, a photosensitizer, a thermal polymerization inhibitor, a resin plasticizer, a pigment dispersant and the like may be used in combination as additives. Silicone compounds modified with alcohols at both ends are used as solids of 1 to
Contains 30% by weight. If the content of the silicone compound is less than 1% by weight of the colorant, blocking cannot be prevented. On the other hand, if it exceeds 30% by weight, the coating surface may be repelled or the photosensitive layer of the next color may not be formed.

The molecular weight of the silicone compound modified with alcohols at both ends is preferably in the range of 500 to 10,000. The molecular weight is
If it is less than 500, blocking may occur depending on the drying conditions of the coating liquid because of its high volatility. Also, if the molecular weight exceeds 10,000, the effect of blocking prevention may be reduced, or the coating surface may have a hexagonal shape. The silicone compound has good compatibility with the photopolymerizable compound and uniformly forms the coated surface of the photosensitive layer during coating. Further, the silicone compound has a function of lowering the surface tension of the photosensitive layer, but since both terminals are modified with alcohol, it has a strong affinity with the resin and migrates to a protective film over time even when stored at 40 ° C. There is no phenomenon to do. Therefore, it has the feature of preventing blocking with time and blocking with heat.

As the photopolymerizable compound, a monomer having an ethylenically unsaturated double bond, a prepolymer or the like can be used, but a compound capable of plasticizing a thermoplastic resin at room temperature is preferable. Typical compounds include 2-hydroxyethyl (meth) acrylate, ethylene glycol diacrylate, diethylene glycol diacrylate, 1,
6-hexanediol di (meth) acrylate, trimethylolpropane triacrylate, pentaerythritol triacrylate, dipentaerythritol hexaacrylate, etc. can be mentioned. These photopolymerizable compounds can be used alone or, if necessary, in combination of two or more. Good.

As the thermoplastic resin, it is possible to use a resin which is thermoplastic and has excellent compatibility with the photopolymerizable compound and which does not have photopolymerizability. For example, polyvinyl chloride, poly (meth)
Acrylic ester, epoxy resin, polyurethane resin, cellulose derivative (eg, ethyl cellulose, cellulose acetate, nitrocellulose), vinyl chloride-vinyl acetate copolymer, polyamide resin, polyvinyl acetal resin, diallyl phthalate resin, butadiene-acrylonitrile copolymer Synthetic rubbers such as the above are listed, and one or more of these thermoplastic resins are used according to the required physical properties.

As the photopolymerization initiator, those having a small absorption mainly in the visible light portion and those having a good compatibility with the photopolymerizable compound are preferable, and examples thereof include benzophenone, benzoin ethyl ether, benzyl dimethyl ketal, and azobisiso. Butyronitrile, 2-chlorothiozanzone, 2-methylthiozanzone, 2-ethylthiozanzone, 2-isopropylthiozanzone, 4'-isopropyl-2-hydroxy-2-
Methyl propiophenone and the like can be mentioned. In addition, a photosensitizer may be used in combination in order to increase the photopolymerization initiation efficiency. As the photosensitizer, aromatic-aliphatic tertiary amine and the like can be used, and examples thereof include 4,4′-bisdiethylaminobenzophenone. Since the photosensitizer may turn yellow, it is selected in consideration of acceleration efficiency, yellowing, compatibility with the initiator, energy of the actinic ray to be used, and wavelength range.

Further, a thermal polymerization inhibitor may be used in order to suppress radicals for photopolymerization. When using a thermal polymerization inhibitor, what is important is the amount added and compatibility, and the amount must be such that it does not interfere with the generation of radicals for photopolymerization and that the radicals are thermally suppressed. Generally, aromatic derivatives such as hydroquinone, p-methoxyphenol, t-butylcatechol, and pyrogallol are used, but compounds other than aromatic compounds may be used in combination. As the colorant applied to the photosensitive layer, conventionally used dyes and pigments such as organic pigments, dyes and carbon black can be used. It is also possible to mix several dyes and pigments in order to obtain the required hue. The pigment or dye added to the photosensitive layer is preferably 5 to 50% by weight of the total solid content, more preferably 9 to 20% by weight.

The protective film may be composed of a single layer or a plurality of layers, but the surface in contact with the photosensitive layer has few fish eyes and has good releasability from the photosensitive layer, and is unnecessary. It is preferable that the plasticizer does not precipitate. The protective film may be provided with a layer having a gas barrier property. The layer having a gas barrier property may or may not be in direct contact with the photosensitive layer. Examples of compounds used for the layer having a gas barrier property include polyvinyl alcohol (PVA) and ethylene vinyl alcohol (EVA).
Polymer compounds such as vOH) can be mentioned. Further, for the purpose of ensuring the rigidity of the image forming material, the protective film may be lined with another strong material on the surface which does not come into direct contact with the photosensitive layer. The material to be lined at this time is
There is no particular limitation.

As such a protective film, a rigid sheet or film of polyethylene terephthalate, biaxially oriented polypropylene, high density polyethylene, etc., one or more of which are bonded with an adhesive, or as much as possible Examples thereof include thin high-density polyethylene, medium-density polyethylene, polystyrene, polypropylene, cellulose acetate, biaxially oriented polypropylene, and the like, and a sheet having gas barrier properties and rigidity, such as polyethylene terephthalate bonded with an adhesive.

[0018]

EXAMPLES The present invention will be described in more detail below with reference to examples, but the present invention is not limited thereto. In the examples, “part” means “part by weight”. [Example 1] A dispersion liquid having the following composition was dispersed in a sand mill for 2 hours and then filtered through a 1-micron filter to prepare a coating liquid for a photosensitive layer. Diallyl isophthalate prepolymer (manufactured by Daiso) 11.40 parts Kayarad DPHA (manufactured by Nippon Kayaku Co., Ltd.) 7.10 parts Kayarad TPGDA (manufactured by Nippon Kayaku Co., Ltd.) 0.90 part Irgacure 907 (manufactured by Nippon Ciba Geigy) 1.20 parts Kayacure DETX-S (Nippon Kayaku Co., Ltd.) 0.60 part Irgacure 369 (Nippon Ciba Geigy Co., Ltd.) 0.20 part Solspers 24000 (ICI Japan Co., Ltd.) 0.10 part KF-6001 (Shin-Etsu Chemical Co., Ltd. both-end alcohol-modified silicone) 0.20 parts MA-7 (manufactured by Mitsubishi Kasei Co.) 2.50 parts R-54 (manufactured by Hoechst Japan Co.) 0.80 parts P-methoxyphenol (manufactured by Tokyo Kasei Kogyo Co., Ltd.) 0.20 parts Methyl ethyl ketone 75.00 parts 12μ transparent support (Toray Co. Q -21), coating and drying the above-mentioned coating liquid for photosensitive layer to form a 2μ photosensitive layer,
Further, a protective film (100 μOPP film) was laminated with a laminator so as to be in contact with the photosensitive layer to obtain an image forming material (black sheet).

The transparent support side of the image forming material and the silver salt surface of the original positive mask were brought into close contact with each other, and an active ray of 50 mj / cm ² was applied by a UV printer (HMW-201KB manufactured by Oak Manufacturing Co., Ltd.). Next, the image forming material and the original positive mask were peeled off, the protective film was further peeled off, the coated paper (pearl coat manufactured by Mitsubishi Paper Mills Co., Ltd.) and the image forming material were adhered to each other, and the first laminator (Taisei Laminator 8B- 700 special type) pressure 4kg / cm ² , passing speed 35cm / min, roller surface temperature 90 ℃
When the transfer was performed by the nip between the rollers under the conditions described above, the photosensitive layer (thickness 2.0 μm) in the unexposed area was transferred, and it was possible to obtain a transfer material that was completely the same in texture as ordinary printed materials. Also, the image forming material was stored in a thermostat at 40 ° C for 1 month, and image exposure was carried out under the same exposure conditions and transferred. When the protective film was peeled off, blocking did not occur at all,
We were able to obtain a transcript that was the same as one month ago.

Example 2 A cyan photosensitive layer coating liquid having the following composition was prepared in the same manner as in Example 1. Diallyl isophthalate toprepolymer (manufactured by Daiso) 11.81 parts Kayarad DPHA (manufactured by Nippon Kayaku Co., Ltd.) 7.49 parts Kayarad TPGDA (manufactured by Nippon Kayaku Co., Ltd.) 0.78 parts Ilkagua 907 (manufactured by Ciba-Gaigi Co., Ltd.) 1.19 parts Kayacure DETX-S (Nippon Kayaku Co., Ltd.) 0.57 parts Ilukagua 369 (Ciba-Gaigi Co., Ltd.) 0.04 parts Rionolble FG7330 (Toyo Ink Mfg. Co., Ltd.) 3.12 parts X-22-160AS 0.22 parts (Shin-Etsu Chemical Co., Ltd. both-end alcohol-modified silicone) ) Methyl ethyl ketone 75.00 parts

A yellow color photosensitive layer coating solution having the following composition was prepared in the same manner as in Example 1. Diallyl isophthalate toprepolymer (manufactured by Daiso) 11.81 parts Kayarad DPHA (manufactured by Nippon Kayaku Co., Ltd.) 7.49 parts Kayarad TPGDA (manufactured by Nippon Kayaku Co., Ltd.) 0.78 parts Ilkagua 907 (manufactured by Ciba-Gaigi Co., Ltd.) 1.19 parts Kayacure DETX-S (Nippon Kayaku Co., Ltd.) 0.54 parts Irukagua 369 (Ciba-Gaigi Co., Ltd.) 0.04 parts Rionolello FG1310 (Toyo Ink Mfg. Co., Ltd.) 3.12 parts KF-6003 (Shin-Etsu Chemical Co., Ltd. both ends alcohol modified silicone) 0.25 parts Methyl ethyl ketone 75.00 Department

A magenta color photosensitive layer coating liquid having the following composition was prepared in the same manner as in Example 1. Diallyl isophthalate toprepolymer (manufactured by Daiso) 11.81 parts Kayarad DPHA (manufactured by Nippon Kayaku Co., Ltd.) 7.49 parts Kayarad TPGDA (manufactured by Nippon Kayaku Co., Ltd.) 0.78 parts Ilkagua 907 (manufactured by Ciba-Gaigi Co., Ltd.) 1.19 parts Kayacure DETX-S (Nippon Kayaku Co., Ltd.) 0.57 parts Ilcagua 369 (Ciba-Gaigi Co., Ltd.) 0.04 parts Riono-redred carmine 6BFG4200 (Toyo Ink Mfg. Co., Ltd.) 3.10 parts F-99-199 0.24 parts (Nippon Unicar Co., both-end alcohol modification) Silicone) Methyl ethyl ketone 75.00 parts

On a support (polyethylene terephthalate sheet) having a thickness of 12 μm, the coating solution for the photosensitive layer was dried to give 1.8
It was applied to have a thickness of μm, and the solvent component was volatilized by drying. Next, a protective film made by laminating 8 μm polypropylene and 100 μm polyethylene terephthalate (T-60 made by Toray) with a 5 μm thick adhesive (Adcote 329A / 329B = 1/1 made by Toyo-Moton) was laminated. Then, image forming materials (cyan sheet, yellow sheet and magenta sheet) were obtained.

The black sheet transfer product obtained in Example 1 is post-exposed, and in the same manner as in Example 1, the yellow sheet, the magenta sheet and the cyan sheet are sequentially transferred and then post-exposed to form an image. Was formed. In each color sheet, even if the protective film was peeled off, blocking of the photosensitive layer on the protective film was not observed. In addition, even when the transfer of each color was performed, no repellency was observed and a good image could be obtained. Furthermore, even if these sheets were stored at 40 ° C for 1 month, no blocking was observed.

Comparative Example 1 An image forming material was manufactured in the same manner as in Example 1 except that the coating liquid was prepared by removing the silicone modified with alcohol at both ends in Example 1. The coated surface of this sheet had a yuzu-like appearance, and the coated surface was not uniform. Further, when the protective film was peeled off, blocking of the photosensitive layer occurred, and the transferred image could not sufficiently reproduce the pattern of the positive mask. [Comparative Example 2] An unmodified polydimethylsiloxane (L-45 manufactured by Nippon Unicar Co., Ltd.) was used in place of the both-end alcohol-modified silicone of Example 2 to prepare a coating solution. A color imaging element was produced. Blocking did not occur in each color sheet immediately after production, but blocking occurred remarkably when left at 25 ° C. for 7 days.

[Comparative Example 3] A coating solution was prepared by replacing the amount of the silicone modified with alcohol at both ends of Example 1 with 1.25 parts.
An image forming material was produced in the same manner as in Example 1. With this sheet, when the protective film was peeled off, blocking of the photosensitive layer did not occur, and good peeling was possible.
The transfer of the photosensitive layer of the next color could not be partially performed. [Comparative Example 4] A coating solution was prepared in the same manner as in Example 1, except that X-22-176B (one-end alcohol-modified silicone manufactured by Shin-Etsu Chemical Co., Ltd.) was used in place of the both-end alcohol-modified silicone of Example 1. An image forming material was produced. This sheet had many repellents and blocking of the photosensitive layer also occurred. In addition, blocking became severe over time. [Comparative Example 5] An image forming material was prepared in the same manner as in Example 1, except that A-151 (a silane coupling agent manufactured by Nippon Unicar Co., Ltd.) was used instead of the silicone modified at both terminals with alcohol in Example 1. Was manufactured. Blocking of the photosensitive layer occurred even after drying at 40 ° C for 30 seconds.

Example 3 Instead of the protective film of Example 2, 25 μRPP (manufactured by Nisseki Goju Co., Ltd.) and 100 μl mirror
A three-color image forming material was manufactured using a protective film obtained by laminating # 100 T type (manufactured by Toray Industries, Inc.) with an adhesive, and a transfer image was formed in the same manner as in Example 2. The RPP was one in which an EvOH layer was formed between the polypropylene layers on both sides by the coextrusion method in order to secure the gas barrier property, and the oxygen permeability was 1.44 cc / m ³ · 24 hours. In each color sheet, even if the protective film was peeled off, blocking of the photosensitive layer to the protective film did not occur. Also, no repelling of the image was observed in the overlapping portion of each color, and good transfer of the image was observed. No blocking occurred even after storage at 25 ° C for 3 months.

The presence or absence of blocking of the photosensitive layer at the time of peeling the protective film is evaluated by attaching the image forming material to the image forming material attaching roll (40 ° C.) of a dedicated transfer machine and exposing the photosensitive film when the protective film is peeled off. The presence or absence of blocking of the functional layer was visually determined.

[0029]

Since the image-forming material of the present invention contains a silicone compound modified with alcohol at both ends, the surface tension of the surface of the photosensitive layer is low and does not cause blocking due to heat. Further, since this silicone compound has a high affinity with the resin, it does not migrate to the protective film at all even if it is stored over time, and blocking does not occur. Further, it does not prevent the transfer of the image forming material for the second and subsequent colors. Therefore, by using the image forming material of the present invention, it is possible to obtain a high-quality transfer material having a texture that is completely the same as that of an ordinary printed material.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Yasuharu Iida 2-3-13 Kyobashi, Chuo-ku, Tokyo Toyo Inki Manufacturing Co., Ltd.

Claims (1)

[Claims] 1. A photosensitive layer containing a colorant is formed on a support, and a protective film is further provided on the photosensitive layer. Imagewise exposure is performed to expose and unexposed areas of the photosensitive layer. In an image forming material that transfers an image to an image receptor such as paper due to the difference in adhesiveness during transfer, the photosensitive layer contains 1 to 30% by weight of a colorant as a solid content of a silicone compound modified with alcohol at both ends. An image forming material characterized by the above.