JP3147583B2 - Image forming material - Google Patents

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 formed by superimposing a single color or a multicolor using the difference in adhesiveness between an exposed portion and an unexposed portion of a photosensitive layer, and as a prepress proof for color proofing, obtains a transferred material similar to a printed material. The image forming material.

[0002]

2. Description of the Related Art In the printing industry, it has been known to use a prepress proof as a means for confirming the finish, color tone, and the like of a finally printed product before printing. The prepress proof includes an overlay method and a surprint method, and the prepress proof is used depending on the image quality to be finally obtained and the purpose of use in plate making and printing processes. In the overlay method, a film in which a photosensitive layer containing a color material corresponding to a color separation mask is provided on a transparent base film is brought into close contact with the mask, exposed and developed, and the respective films are overlaid. Perform calibration.

[0003] The surprint method has a high utility value since a hard copy is obtained unlike the overlay method, and for example, as described in US Patent Nos. 3060023, 3060024 and 3060025. In this method, several layers of photopolymer-photosensitive layers are laminated on a single support to sequentially form color-separated images. Also, JP-A-59-97410,
There is also a prepress proof that can be used for both the overlay method and the surprint method as described in Japanese Patent Application Laid-Open No. Sho 61-1885377. Use this method if you just want to check characters etc. according to the purpose of use.
The versatility is large in that the hard copy can be obtained by checking only the burley and obtaining a hard copy for checking a delicate color portion such as a picture, by transferring the hard copy to the transfer target. However, there is a disadvantage that the working environment is deteriorated due to the necessity of a developing step using an organic solvent.

On the other hand, the present inventors have formed a photosensitive layer containing a dye and / or a pigment on a transparent support, exposed the image, and carried out the tackiness in the transfer of the exposed and unexposed portions of the photosensitive layer. And a prepress pull obtained by transferring an image to an image receptor by cohesion failure of a photosensitive layer between roll nips using an image forming material such as paper which transfers an image to an image receptor. Unlike conventional pre-press proofs, the image and texture look very similar to the actual printed matter because there is no layer such as an adhesive layer between the printing material and the image forming material, unlike the conventional prepress proof. Has already been headed. These image-forming materials usually comprise three layers: a transparent support, a photosensitive layer containing a dye and / or a pigment, and a protective film. When using the image forming material, the transparent support is brought into close contact with the image surface of the mask master and the like, and image exposure is performed from the mask side.
Next, the protective film is removed, and the photosensitive layer and the image receptor are transferred between the nipples while applying heat and pressure.

[0005] However, since these image forming bodies are formed by forming a thinner photosensitive layer on a thin support and then laminating a protective film, fine coatings on the surface of the support or the protective film may cause the coating surface to be coated. Holes tend to occur, so-called pinholes. In order to form a uniform coating surface, tension is applied to the support to keep the coating surface smooth, but the thickness of the support and the protective film differ, resulting in a difference in tension, and a reduction in tension after lamination. Is caused between the protective film and the photosensitive layer. Therefore, in the photosensitive layer, the shift of the photosensitive layer based on the displacement is more likely to occur. In particular, since the ink color is easily perceived by human vision, it is necessary to solve this problem.

[0006] Normally, carbon black is used for the black color. However, with carbon black alone, countless pinholes are generated on the coated surface, and it is difficult to reproduce colors that require jet-black feeling. Therefore, to adjust the color tone by adding a blue dye to give a jet-black feeling, the pinholes were reduced but still remained, and the photosensitive layer became more remarkable with the passage of time. In particular, when heated for several days, the dispersion state of the dye in the photosensitive layer was reduced, and a reduction in the color density became a problem.

[0007]

The present inventors have conducted intensive studies to solve the above-mentioned problems. As a result, the photosensitive layer containing an alkali blue lake, carbon black and a phthalocyanine compound having a specific structure has a jet-black feeling. In addition, the present inventors have found that the number of pinholes is small and that a decrease in transmission density due to more (variation in film thickness) is prevented, and the present invention has been completed.

[0008]

According to the present invention, a photosensitive layer containing a colorant is formed on a support, and a protective film is further formed on the photosensitive layer. In an image-forming material for transferring an image to an image receptor, such as paper, due to a difference in adhesiveness between the exposed portion and the unexposed portion in the transfer of the layer, the photosensitive layer has an alkali blue lake, carbon black and a compound having the following structure The present invention provides an image forming material containing: Phc─ (SO ₃ H.H ₂ N (CH ₂ ) _n CH ₃ ) _m (where Phc is a copper phthalocyanine residue and n is 5 to
15 represents an integer, and m represents an integer of 1 to 4. )

The support is preferably made of a material that is stable to heat, chemicals, light, etc., and that sufficiently transmits actinic rays. For example, cellulose acetate, polystyrene, polyvinyl chloride, polyethylene terephthalate,
Examples include films or sheets of polycarbonate, polypropylene and the like, and polyethylene terephthalate is particularly preferred in terms of transparency, heat stability, dimensional stability and the like. The photosensitive layer is composed of an alkali blue lake, carbon black, a phthalocyanine compound having the above structure, a photopolymerizable compound, a thermoplastic resin, and the like.
It is a layer having a thickness of 5μ.
Photosensitizers, thermal polymerization inhibitors, resin plasticizers, pigment dispersants and the like may be used in combination.

As alkali blue lakes, Pigment Blue 19 (CI42750: 1), Pigment Blue 18
(CI42770: 1), Pigment Blue 61 (CI42765:
1), Pigment Blue 57 (CI42795), Pigment Blue 56 (CI42800), Solvent Blue 23 (CI4295)
760), Solvent Blue 3 (CI42775) and the like are used in 5 to 40 parts by weight based on 100 parts by weight of carbon black.
If the amount is less than 5 parts by weight, a sufficient effect of reducing pinholes cannot be obtained and jet-blackness cannot be obtained. Furthermore, the coloring concentration of the photosensitive layer over time cannot be sufficiently stabilized. Also, 40
Exceeding the weight part, the hue becomes blue, and the color tone is not sufficient for black ink. As carbon black, pigment black 7 commonly used in printing inks and the like is used.
(CI77266) is used. It should be noted that the use of carbon black alone does not provide a jet-black feeling and increases pinholes on the coated surface over time.

The phthalocyanine compound having the above structure functions to maintain a stable dispersibility of the alkali blue lake in the photosensitive layer, and at the same time, even if a difference in tension between the support and the protective film occurs, It also works to suppress the twist. The phthalocyanine compound is used in an amount of 1 to 100 parts by weight of alkali blue lake and carbon black.
Used 10 parts. If the amount is less than 1 part by weight, the effect of reducing the twist of the photosensitive layer and the number of pinholes cannot be obtained. The colorant in the photosensitive layer is suitably from 5 to 50% by weight of the total solids, more preferably from 9 to 20% by weight.

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. Representative compounds include 2-hydroxyethyl (meth) acrylate, ethylene glycol diacrylate, diethylene glycol diacrylate,
6-hexanediol di (meth) acrylate, trimethylolpropane triacrylate, pentaerythritol triacrylate, dipentaerythritol hexaacrylate, and the like. These photopolymerizable compounds may be used alone, or two or more as needed. Is also good.

[0013] As the thermoplastic resin, a thermoplastic resin having no compatibility with a photopolymerizable compound and having no photopolymerizability can be used. For example, polyvinyl chloride, poly (meth)
Acrylic esters, epoxy resins, polyurethane resins, cellulose derivatives (eg, ethyl cellulose, cellulose acetate, nitrocellulose), vinyl chloride-vinyl acetate copolymers, polyamide resins, polyvinyl acetal resins, diallyl phthalate resins, butadiene-acrylonitrile copolymers These thermoplastic resins may be used alone or in combination of two or more depending on the required physical properties.

As the photopolymerization initiator, those which mainly absorb little in the visible light region and those which have good compatibility with the photopolymerizable compound are preferable. For example, benzophenone, benzoin ethyl ether, benzyldimethyl ketal, azobisisobutane Butyronitrile, 2-chlorothiozanzone, 2-methylthiozanzone, 2-ethylthiozanzone, 2-isopropylthiozanzone, 4'-isopropyl-2-hydroxy-2-
Methyl propiophenone and the like. Further, in order to increase the photopolymerization initiation efficiency, a photosensitizer may be used in combination. As the photosensitizer, an aromatic-aliphatic tertiary amine or the like can be used, and for example, 4,4′-bisdiethylaminobenzophenone can be used. Since the photosensitizer may be yellowed, the photosensitizer is selected in consideration of the acceleration efficiency and yellowing, compatibility with the initiator, the energy of the active light beam to be used, and the wavelength range.

Further, a thermal polymerization inhibitor may be used to suppress radicals for photopolymerization. When using a thermal polymerization inhibitor, what is important is the amount of addition and compatibility, and the amount of radicals for photopolymerization should not be disturbed, and the radicals must be 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.

In the photosensitive layer, one or more silicone compounds such as epoxy-modified silicone at both ends and (meth) acryloyl-modified silicone can be used as a solid content of 0.01 to 30% by weight of the colorant. The silicone compound has good compatibility with the photopolymerizable compound and uniformly forms the coated surface of the photosensitive layer. In addition, the above-mentioned silicone compound has a function of lowering the surface tension of the photosensitive layer.
Strong affinity with resin, no phenomenon of transfer to protective film over time even at 40 ° C storage. Therefore, it has the feature of preventing blocking over time and blocking during heating. The amount of the silicone compound is 0.01% by weight of the colorant
If it is less, blocking cannot be prevented. Also, 30
If the amount is more than 10% by weight, problems occur such that repelling occurs on the coated surface and an image of the next color cannot be formed.

The protective film may be composed of a single layer or a plurality of layers. However, the surface in contact with the photosensitive layer has few fish eyes, has good releasability from the photosensitive layer, and is unnecessary. Those in which the plasticizer does not precipitate are preferred. The protective film may be provided with a layer having gas barrier properties. The layer having gas barrier properties may or may not be in direct contact with the photosensitive layer. Compounds used in the layer having gas barrier properties include, for example, polyvinyl alcohol (PVA) and ethylene vinyl alcohol (E
vOH) and the like. Further, for the purpose of securing the rigidity of the image forming material, the protective film may be lined with another material having high rigidity on a surface that is not in direct contact with the photosensitive layer. At this time,
There is no particular limitation.

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

[0019]

EXAMPLES Hereinafter, the present invention will be described in more detail by way of examples, but the present invention is not limited thereto. In the examples, parts mean parts by weight. The copper phthalocyanine compounds (A) to (D) represent compounds having the following structures. Phc─ (SO ₃ H.H ₂ N (CH ₂ ) _n CH ₃ ) _m (where Phc represents a residue of copper phthalocyanine) Phthalocyanine compound (A): n = 10, m = 1 Phthalocyanine compound (B ): N = 11, m = 1 Phthalocyanine compound (C): n = 11, m = 2 Phthalocyanine compound (D): n = 7, m = 1

Example 1 A dispersion 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 solution for a photosensitive layer. Diallyl isophthalate prepolymer (Daiso) 11.40 parts Kayarad DPHA (Nippon Kayaku) 7.10 parts Kayarad TPGDA (Nippon Kayaku) 0.90 parts Irgacure 907 (Nippon Ciba Geigy) 1.20 parts Kayacure DETX-S (Nippon Kayaku) 0.60 part Irgacure 369 (Nippon Ciba-Geigy) 0.20 part Phthalocyanine compound (A) 0.08 part MA-7 (Mitsubishi Kasei) 2.50 parts Pigment Blue 57 0.30 part X-22-169AS ( Shin-Etsu Chemical Co., Ltd.) 0.20 part P-methoxyphenol (Tokyo Kasei Kogyo Co., Ltd.) 0.20 part Methyl ethyl ketone 75.00 parts Coating solution for the photosensitive layer is coated on a 12μ transparent support (Toray Q-21). Dry to form a 2μ photosensitive layer,
Further, a protective film (100 μ OPP 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 was brought into close contact with the silver halide surface of the original plate positive mask, and actinic rays of 50 mj / cm ² were applied by a UV printer (HMW-201KB manufactured by Oak Manufacturing Co., Ltd.). Next, the image forming material and the original plate positive mask are peeled off, the protective film is further peeled off, and the coated paper (pearl coat manufactured by Mitsubishi Paper Mills) is brought into close contact with the image forming material, and the first laminator (Taishi Laminator 8B- 700 special type), pressure 4kg / cm ² , passage speed 35cm / min, roller surface temperature 90 ℃
When the image was transferred by the nip between the rollers under the conditions described above, the unexposed portion of the photosensitive layer (thickness: 2.0 μm) was transferred, and a transferred material having the same texture as a normal printed material could be obtained. The image forming material was stored in a thermostat at 40 ° C for one month, and the pinholes on the coated surface and the twist of the photosensitive layer were compared with those immediately after coating. Did not. The transferred image was the same as one month ago.

Example 2 On a 12 μm support (polyethylene terephthalate sheet), a coating solution for a photosensitive layer having the following composition prepared in the same manner as in Example 1 was dried to a film thickness of 1.8.
The solution was applied to a thickness of μm, and the solvent component was evaporated by drying. Next, a protective film formed by laminating 8 μm polypropylene and 100 μm polyethylene terephthalate (Toray T-60) with a 5 μm thick adhesive (Toyo Morton Adcoat 329A / 329B = 1/1) was laminated, and image formation The material (ink sheet) was obtained. Diallyl isophthalate prepolymer (manufactured by Daiso) 11.81 parts Kayarad DPHA (manufactured by Nippon Kayaku) 7.49 parts Kayarad TPGDA (manufactured by Nippon Kayaku) 0.78 parts Irukagua 907 (manufactured by Ciba-Geigy) 1.19 parts Kayacure DETX-S (Japan) 0.57 parts Irkagua 369 (manufactured by Ciba-Geigy Corporation) 0.04 parts Phthalocyanine compound (A) 0.07 parts MA-7 (manufactured by Mitsubishi Kasei) 2.50 parts Pigment Blue 57 0.30 parts X-22-169B (manufactured by Shin-Etsu Chemical Co., Ltd.) ) 0.22 parts Methyl ethyl ketone 75.00 parts

Example 3 A coating solution for a photosensitive layer having the following composition was prepared in the same manner as in Example 1, and an image forming material (black sheet) was obtained in the same manner as in Example 2. Diallyl isophthalate prepolymer (manufactured by Daiso) 11.81 parts Kayarad DPHA (manufactured by Nippon Kayaku) 7.49 parts Kayarad TPGDA (manufactured by Nippon Kayaku) 0.78 parts Irukagua 907 (manufactured by Ciba-Geigy) 1.19 parts Kayacure DETX-S (Japan) 0.54 parts Irkagua 369 (Ciba-Geigy Corporation) 0.04 parts Phthalocyanine compound (B) 0.04 parts MA-7 (Mitsubishi Kasei) 2.50 parts Pigment Blue 57 0.30 parts KF-105 (Shin-Etsu Chemical) 0.25 Parts methyl ethyl ketone 75.00 parts

Example 4 Phthalocyanine Compound (B)
Was replaced with the phthalocyanine compound (C), and an image forming material (black sheet) was obtained in the same manner as in Example 3. Example 5 An image forming material (black sheet) was obtained in the same manner as in Example 3 except that Pigment Blue 57 was replaced with Pigment Blue 61. Example 6 An image forming material (black sheet) was obtained in the same manner as in Example 3 except that the phthalocyanine compound (B) was changed to the phthalocyanine compound (D).

When the image forming materials obtained in Examples 2 to 6 were transferred in the same manner as in Example 1, it was possible to obtain a transferred material having the same material appearance as a normal printed material. The image forming material was stored in a thermostat at 40 ° C for one month, and the pinholes on the coated surface and the twist of the photosensitive layer were compared with those immediately after coating. Did not. The transferred image was the same as one month ago. Furthermore, even when the protective film was peeled off, no blocking of the photosensitive layer to the protective film was observed, and the peelability immediately after lamination was sufficiently maintained after three months. .

COMPARATIVE EXAMPLE 1 A coating solution was prepared from Example 1 except for the phthalocyanine compound (A) to form an image forming material. When this ink sheet is stored in a 40 ° C environment for one month, the coated surface becomes more transparent and the transmission density around the edge of the sheet becomes 0.08.
Dropped. Also, pinholes increased. [Comparative Example 2] An image forming material was formed by preparing a coating liquid except for Pigment Blue 57 (alkali blue toner) of Example 1. This ink sheet was a sheet that easily formed pinholes on the coated surface and had no jet-black feeling. Also, 40 ℃
When stored in January environment, pinholes increased on the coated surface. [Comparative Example 3] A coating solution was prepared using a high molecular weight dispersant (SOLSPERS 24000 manufactured by IC Japan, Inc.) in place of the phthalocyanine compound (A) of Example 1,
An image material was formed. Although it was a coating liquid with excellent dispersibility, the coating surface was generated when stored in a 40 ° C environment for one month.
A decrease in concentration was observed.

Example 7 In place of the protective film of Example 2, 25 μRPP (manufactured by Nishiishi Kazuki) and 100 μL mirror were used.
An image forming material was formed using a protective film obtained by laminating # 100 T type (manufactured by Toray Industries Inc.) via an adhesive. The RPP is obtained by forming an EvOH layer between the polypropylene layers on both sides by a co-extrusion method in order to secure gas barrier properties, and has an oxygen permeability of 1.44 cc / m ³ ···
24 hours. The black sheet was stored in a thermostat at 40 ° C for 1 month, and the pinholes on the coated surface and the twist of the photosensitive layer were compared with those immediately after coating. The transferred image was not different from one month ago. Furthermore, even when the protective film was peeled off, no blocking of the photosensitive layer to the protective film was observed.
The peelability immediately after lamination was sufficiently maintained even after three months.

Evaluation of the presence or absence of blocking of the photosensitive layer at the time of peeling of the protective film is performed by mounting the image forming material on the image forming material mounting roll (40 ° C.) of the exclusive transfer machine, and removing the protective film when the protective film is peeled off. The presence or absence of blocking of the active layer was visually determined.

[0029]

The image forming material of the present invention can form a jet-black image by the action of the phthalocyanine compound on the alkali blue toner and carbon black. In addition, pinholes are less likely to occur when forming the coating surface. Furthermore, the image forming material hardly changes with time when stored, and phenomena such as an increase in pinholes and a twist in the photosensitive layer are reduced. In addition, a stable photosensitive layer without a decrease in density can be obtained even when stored at a temperature higher than room temperature of about 40 ° C.

──────────────────────────────────────────────────続 き Continuation of the front page (72) Inventor Yasuhisa Iida 2-3-1 Kyobashi, Chuo-ku, Tokyo Toyo Ink Manufacturing Co., Ltd. Examiner Yoshiko Maeda (56) References JP-A-4-220649 (JP, A) JP-A-58-83860 (JP, A) JP-A-64-74278 (JP, A) JP-A-56-54444 (JP, A) JP-A-4-63870 (JP, A) JP-A-64 -77622 (JP, A) JP-A-2-262153 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) G03F 7/004 G03F 3/10

Claims (1)

(57) [Claims] 1. A photosensitive layer containing a colorant is formed on a support, and a protective film is further formed on the photosensitive layer. The photosensitive layer is exposed to light, and exposed and unexposed areas in the photosensitive layer are provided. Due to the difference in tackiness in the transfer of the image, the photosensitive layer of the image forming material for transferring an image to an image receptor, such as paper,
An image-forming material comprising an alkali blue lake, carbon black and a compound having the following structure. Phc─ (SO ₃ H.H ₂ N (CH ₂ ) _n CH ₃ ) _m (where Phc is a copper phthalocyanine residue and n is 5 to
15 represents an integer, and m represents an integer of 1 to 4. )