JPS6263930A - Image forming material - Google Patents

Abstract

PURPOSE:To obtain an image forming material which prevents the adhesion between a base surface or back layer surface and the surface of a photosensitive resin layer or the surface of a protective layer and the reticulation by incorporating silica particles subjected to a hydrophobic surface treatment into the uppermost layer on the photosensitive resin layer side. CONSTITUTION:This image forming material is formed by incorporating the silica particles subjected to the hydrophobic surface treatment into the uppermost layer on the photosensitive resin layer side. The average particle sizes of the silica particles are preferably about 0.01-10mu, more particularly preferably about 0.01-1mu. The hydrophobic silica particles are obtd. by binding a compd. having a hydrophobic group by primary bonding or secondary bonding such as Van der Waals force to the surface of silica particles so as to have the hydrophobic characteristic. The amt. of the silica particles to be added is more preferably about 10-30wt% by the weight of the binder in the uppermost layer.

Description

DETAILED DESCRIPTION OF THE INVENTION "Field of Industrial Application" The present invention relates to negative or positive image forming materials used for printing plates, return films, color test prints, dry film resists, and the like.

``Conventional techniques'' Conventionally, image forming materials used in various fields such as printing, photography, and microfabrication of metals, etc., are basically supported (or temporary supports in transfer-type image forming materials). It consists essentially of a photosensitive resin layer made of a photopolymer provided thereon.

For example, a transfer type image forming material (photosensitive transfer sheet) having such a configuration is used for color proofing. Color proofing sheets for color proofing are made by exposing and developing an image forming material through a separation mesh film for each color plate to form a separation image on a photosensitive resin layer, and then applying this separation image to an arbitrary support ( image-receiving surface). Moreover, a multicolor image can be obtained by repeating the process of transferring further separated images of different colors onto the above-mentioned support.

Furthermore, in order to simplify the transfer process, image forming materials are known in which a release layer is provided between the support and the photosensitive resin layer (Japanese Patent Publication No. 4T No. 1Q, Japanese Patent Publication No. 4T No. 7) −≠
/Refer to Publication No. 130, etc.).

In any case, the image-forming material essentially consists of a support and a photosensitive resin layer, and if necessary, a retention layer is provided on the photosensitive resin layer, but it is manufactured by a conventional method. It is done. That is, after coating a coating solution for a photosensitive resin layer (hereinafter abbreviated as photosensitive source) on a long sheet-shaped support made of polyethylene terephthalate or the like, it is heated and dried at a constant temperature (drying step), It is manufactured by continuous winding (winding process). When a protective layer is provided, it is manufactured by once winding up, applying a coating solution for preservation onto the photosensitive resin layer, and drying it. Further, the wound image forming material is subjected to post-processing such as cutting into a desired standard size (processing step), and is manufactured into a product.

However, adhesion between the surface of the support of such image forming materials, printing plates, return films, dry film resists, etc., or the back layer surface provided on the surface and the surface of the photosensitive resin layer, or the surface of the protective layer is difficult. It has the disadvantage that it tends to occur.

In particular, the photopolymerizable photosensitive resin layer is basically composed of a photopolymerizable monomer, a photopolymerization initiator, and an organic polymerization binder,
Since the nitrate acts like a kind of plasticizer for the organic polymeric binder, the photopolymerizable photosensitive resin layer is formed in a slightly soft state.

Although this is necessary to improve image formation, it also makes it easier for the above-mentioned adhesion phenomenon to occur.

Furthermore, especially when a protective layer is provided, crepe-like wrinkles, a so-called reticulation phenomenon, may occur on the surface after several days or more have passed after manufacture.

As a method for solving these drawbacks, a method is known in which a rough matting agent is added to the photosensitive resin layer and/or the protective layer. However, with this method, if enough matting agent is added to completely prevent adhesion,
Problems arise in that good image quality cannot be obtained due to haze, and a sufficient effect on reticulation phenomenon cannot be obtained.

"Problems to be Solved by the Invention" The present invention aims to provide an image forming material in which adhesion and reticulation between the support surface or pack layer surface and the photosensitive resin layer surface or retaining layer surface are prevented. This is the purpose.

"Means for Solving the Problems" The present invention provides an image forming material having a support and a photosensitive resin layer provided thereon, in which the uppermost layer on the side of the photosensitive resin layer is subjected to hydrophobic surface treatment. This can be achieved by using an image forming material characterized by containing silica particles.

A typical image forming material of the present invention has a structure in which a pack/if, a support, a photosensitive resin layer, and a protective layer are provided in this order. However, the image forming material of the present invention is not limited to the above-mentioned configuration; for example, the back layer and/or protective layer may be bad, or there may be a gap between the support and the photopolymerizable photosensitive resin. The structure may include various intermediate layers.

The image forming material of the present invention having the above structure can be produced, for example, by the method described below.

As the material for the support, a substance that is chemically and thermally stable and has flexibility is used. It may be transparent to actinic light if necessary.

Specifically, for example, polyolefins such as polyethylene and polypropylene, polyvinyl chloride, polyvinyl halides such as j-polyvinylidene chloride, cellulose derivatives such as cellulose acetate, nitrocellulose, and cellophane, polyamides, polystyrene, Examples include polycarbonate and polyimides. Particularly preferred among these is biaxially oriented polyethylene terephthalate film, which is excellent in dimensional stability and transparency.

A backing layer can be provided on the surface of this support opposite to the side on which the photopolymerizable photosensitive resin layer is provided. An example of the back layer is a layer in which a matting agent is contained and supported in a dispersed state in acetyl cellulose. Examples of acetylcellulose include monoacetylcellulose, diacetylcellulose, triacetylcellulose, and acetylbutylcellulose.

The degree of acetylation (degree of acetylation) of acetylcellulose is preferably in the range of ≠0-40%, and the average degree of polymerization is preferably in the range of 10-1100.

Examples of matting agents include silicon dioxide-Otsuichi (including colloidal silica), aluminum oxide, aluminum silicate, aluminum hydroxide, titanium dioxide,
Fine particulate inorganic compounds such as calcium carbonate and zinc oxide,
and organic polymers insoluble in solvents such as crosslinked polystyrene in the form of fine particles. The average particle size of these matting agents varies depending on the thickness of the backing layer, but is preferably in the range θ, 00j-10 μm. The above matting agents may be used alone or in combination of two or more.

The ratio of acetylcellulose to the matting agent is preferably adjusted so that the content ratio of the matting agent to acetylcellulose is in the range of / to weight ratio. If the content ratio of the matting agent exceeds this range, it may not be sufficient when taking into consideration all aspects such as the adhesiveness between the back layer and the support.

In forming the back layer, first, the acetyl cellulose and a matting agent are mixed using a suitable solvent to prepare a coating solution. In this case, solvents include, for example, ketones such as acetone, methyl ethyl ketone, and cyclohexanone; acetate esters such as methyl acetate and ethyl acetate;
Ethers such as methyl cellosolve, dioxane, and tetrahydrofuran; and methylene chloride and diacetone alcohol can be mentioned. These solvents may be used alone or as a mixed solvent of two or more.

The back layer can be formed by applying the above coating solution onto a support using a conventional method and drying it.

Incidentally, an etching agent such as resorcinol or an antihalation agent may be added to the coating liquid, if necessary, for the purpose of increasing the adhesion to polyethylene terephthalate (support).

The thickness of the back layer is generally preferably in the range of o, oi to j .mu.m, particularly preferably in the range of 0.7 to 0.1 .mu.m.

Next, a photosensitive resin layer is provided on the other side of the support.

When the photosensitive resin layer is a photopolymerizable photosensitive resin layer, it is usually a polyfunctional vinyl monomer or vinylidene compound that has a boiling point of 1ro0c or more at normal pressure and can form a photopolymer by addition polymerization. It consists of a monomer compound such as, an organic polymer binder, and a photopolymerization initiator activated by actinic rays, and a thermal polymerization inhibitor is added as necessary.

The vinyl monomer or vinylidene compound that can be used to form the photopolymerizable photosensitive resin layer is preferably, for example, an unsaturated ester of polyol, particularly an ester of acrylic acid or methacrylic acid. Specific examples include ethylene glycol diacrylate, glycerin triacrylate, polyacrylate, ethylene glycol dimethacrylate,
, 3-prononediol dimethacrylate, polyethylene glycol dimethacrylate), /, , 2.44-butane trio-root trimethacrylate, trimethylolethane triacrylate, pentaerythritol dimethacrylate, pentaerythritol trimethacrylate, pentaerythritol Tetra methacrylate, pentaerythritol diacrylate, pentaerythritol triacrylate, pentaerythritol tetraacrylate, dipentaerythritol-polyacrylate, /, J-pronohair dioludiacrylate), /, j-pentanedio-
Mention may be made of bisacrylates, bismethacrylates and similar compounds of polyethylene glycol with a molecular weight in the range from 1.200 to 1100.

As the monomer compound, unsaturated amides can also be used, examples of which include unsaturated amides of acrylic acid and methacrylic acid with α,ω-diamines and ethylene bismethacrylamide. The alkylene chain of unsaturated amides may be open by carbon atoms. However, the photopolymerizable polymer is not limited to these compounds.

Examples of the photopolymerization initiator include benzophenone, Michler's ketone (4t, +'-bis(dimethylamino)benzophenone), ≠, 4I'-bis(dimethylamino)
Aromatic ketones such as benzophenone, goomethoxy-t'-dimethylaminobenzophenone, coethyl anthraquinone, phenantraginone, and other aromatic ketones; such as benzoin, benzoin methyl ether, benzoin ethyl ether, and benzoin phenyl ether. Benzoin ethers: methylbenzoin,
Ethylbenzoin and other benzoias i fx
LaUVc2- (o-chlorophenyl)-ri.

j-diphenylimidazole, λ-(0-chlorophenyl)-4', -t-(m-methoxyphenyl)imidazole, -2-(o-fluorophenyl)-≠1. t-diphenylimitasol dimer 1
λ-(0-methoxyphenyl l-4,j-diphenylimidazole dimer, J-(p-, methoxyphenyl)-
1jl, t-diphenylimidazole dimer, Ko, Hiro-
Di(p-methoxyphenyl)-1-phenylimidazole dimer, Co(co).

gudimethoxyphenyl)-4t, t-diphenylimidazole dimer, co(p-methylmercaptophenyl)-p,t-diphenylimitasol dimer, and U.S. Pat. Hiroshi 77, evening edition, British Patent No. 1,014
7. 2. as described in U.S. Pat. g,,t-)
Mention may be made of lyacrylimidazole dimers.

As the organic polymer binder, vinyl polymer substances are particularly preferred from the viewpoint of compatibility with the above-mentioned monomer compounds and photopolymerization initiators. Examples of vinyl polymer substances include polyvinyl chloride, polyacrylic acid, polymethyl acrylate, polyethyl acrylate, polybutyl acrylate,
Various examples include, but are not limited to, polymethacrylic acid, polymethyl methacrylate, polyvinyl ether, polyvinyl acetal, and copolymers thereof.

Here, the proper mixing ratio of the seven-mer compound and the organic polymer binder varies depending on the combination of the monomer compound and the organic polymer binder used, but in general, /:/
θ~,! A range of :/ (weight ratio) is preferable. In addition, at this time, the amount of the photopolymerization initiator added is θ relative to the weight of the heptamer compound used.

A range of O/ to θ weight ratio is preferable.

Examples of thermal polymerization inhibitors include p-methoxyphenol, hydroquinone, alkyl- or aryl-substituted hydroquinone, tertiary-butylcatechol, pyrogallol, naphthylamine, β-naphthol, zenathiazine, pyridine, nitrobenzene, o-torquinone, and aryl phosphite. However, it is not limited to these.

In addition, when the photosensitive resin layer is a photo-dissociable resin layer, as a photo-dissociable compound, US Pat.
Orthoquinone diazide compound described in No. j4t74'+j etc., JP-A-14-1973-/73μ! Compounds having an orthoester group in the main chain described in JP-A No. 4
Examples include compounds having a silyl ether group in the main chain as described in No. O-3714t.

In this case, the organic salt coalescing binder is not necessarily required.
- Although it is not necessary, novolac type phenol resin etc. can be used. The binder can be used in a range of approximately po to o o weight of the photo-dissociable resin layer.

When the photosensitive resin layer is a photopolymerizable resin layer, the effect of the present invention is particularly remarkable because the layer is soft.

The thickness of the photosensitive resin layer is generally in the range of 0.2 to 10 μm, preferably in the range of 1 to 10 μm.

For details on the materials of these photosensitive resin layers and their formation methods, please refer to Kutoe No. 4tA-/132, No. 4I7-jjjlZ, No. 1r3o, No. 7-g1r3o,
JP-A 4t, r-23337, JP-A 41/, JP-A 10/, JP-A! It is described in various publications such as Tartuff/≠No.0. The effect of the present invention is that the hardness of the photosensitive resin layer has a softening point of t000 according to the Vieat method.
Below, it is particularly noticeable in % when the temperature is below 40°C.

When a colored substance is used, the colored substance may be contained in the photosensitive resin layer, or may be contained in a separate color/4t material layer. The coloring material layer can be provided either above or below the photosensitive resin layer, but the sensitivity of the photosensitive resin layer in the image exposure process (
From the viewpoint of photopolymerizability, it is preferable to provide a photosensitive resin layer on the coloring material layer. Furthermore, known pigments and dyes can be used as the coloring substance. For details of coloring substances and coloring material layers, see, for example, Japanese Patent Application Laid-Open No. 97/110.
It is disclosed in the publication No.

Furthermore, the image forming material of the present invention prevents a decrease in sensitivity due to oxygen! A protective layer with low oxygen permeability can be provided from the viewpoint of H. The protective layer may be made of, for example, polyvinyl alcohol, polyvinyl acetate, methyl vinyl ether/maleic anhydride copolymer, polyvinylpyrrolidone, gelatin,
It can be formed by applying a solution of a polymeric substance such as gum arabic and drying it. The thickness of the protective layer is θ, /μ to jμ, preferably θ9.2μ to 3μ,
More preferably, it is Oo, about 2μ to λμ.

The hydrophobic silica particles used in the present invention are added to this protective layer or, if no protective layer is provided, to the photosensitive resin layer that is the uppermost layer. Preferred silica particles have an average particle size of about 0.01-10μ, particularly preferably about 0.
It is 0/-/μ.

Hydrophobic silica particles are produced by adding a compound having a hydrophobic group to the surface of the silica particles, or by Van d@rWaals
They are bonded together by a combination of two components, such as force, to impart hydrophobicity.

Examples of this type include those in which various reactions are performed on 5t-OH groups on the surface of silica particles. These are shown below. Hereinafter, R represents an alkyl group.

(il 5i-OH+ROH-+5i-0-R(II
) 8l-OH+S02α→5i-o-αS i −
0−('l+ RM g B r −+S i −0−
R(Ilil S 1-OH+S tα4→S i
-0-8i Q! ! a(iV)sioH+5iF4-
+5i-o-siF'a(V) 5iOH+(?/-
8t(R)3-+5i-0-8iR3(Vll) 5
10H+CH2N2-+5iOCH3(IX) 5i
OH+SO2α→810α(X) 510H+Ti(
144→5iOHTi(J4l 7-) There are various other methods such as a method of surface treatment with a silane coupling agent, a method of adsorbing a surfactant, and a method of adsorbing a monomer to form a polymer.

An example of this can be found in “Th@Chemist” by ILER.
yof 5iLiCA' A Wiley-Int
ersai*naaPublication, JOHN
WILEY & 5ONS/Pj70 published in 1972
~ J Tata, Published by Soft Giken Publishing Department, Powder Surface Modification Technical Data Collection (published in 1999, written by Koishi et al.).

Among these products, Aerosil R manufactured by Nippon Aerosil ■
-972, Catalysts & Chemicals Industry ■ (2) O8CAL, 08C
AP, Thyroid 271° JOIr made by Fuji Devirin■
%λsj, /41. /l, etc. are commercially available and can be easily obtained.

In the method of using the silica particles of the present invention, since they can be dispersed in an organic solvent, they can be used by being dispersed in an organic solvent-based coating solution for a photosensitive resin layer or a protective layer. In the case of an aqueous coating solution, it can also be emulsified and dispersed.

In the present invention, it is particularly preferable to dissolve the hydrophilic resin in an aqueous solvent and use it as an emulsified dispersion in a coating solution for a protective layer.

・ Addition of silica particles used in the present invention, Mogami 1
- to the binder (however, if the uppermost layer is a photosensitive resin layer, in addition to the binder, a monomer compound or a photodissociation compound is added to the total wrinkles) / heavy leaves ~ to weight officer,
It is preferably added in an amount of JJti4 to 4'1)tt96, more preferably 10 to 30% by weight.

"Example" Next, examples of the present invention and comparative examples are listed.

However, the following aspects do not limit the present invention.

Example/ A solution having the following composition was prepared as a coating solution for forming a pack layer.

Back layer coating liquid resorcin (etching agent 1.2.J'h diacetylcellulose (acetic acid 1f: 0.3 to 9j1
10, j, average degree of polymerization: 16θ acetate flex v -A c, :, made by Daicel ■) Ni-oxidized ion oxide (average particle size: 41-θmμ θ, /K
gTT-Otsu0θ, manufactured by Nippon Aerosil ■) Methanol I K, 9
Methyl T-methylketone JOKg This coating solution was uniformly applied onto a polyethylene terephthalate film (support, thickness: 100 μm, length: 000 ml) and dried (drying temperature: 720°C) [7. After providing a back layer having a thickness of 0.3 μm and consisting essentially of diacetyl cellulose and silicon dioxide, the film was wound up.

Next, a solution having the following composition was prepared as a coating solution for forming a photosensitive resin layer. In this case, a carbon dispersion having the following composition was prepared separately in an 8!4 product and mixed.

Carbon dispersion carbon black ta, rK41 (
MA-too, manufactured by Mitsubishi Kasei Corporation) Benzyl methacrylate meth/C4tKg acrylic acid copolymer (molar ratio near, 2/27, intrinsic viscosity of methyl ethyl ketone solution of t'c 20, lλcps) Methyl ethyl ketone Jj, plQ methyl heptalosolp acetate 3t,? b Coating liquid for photosensitive resin layer Methyl ethyl ketone 11Kg Methyl cellosolve acetate 7,! 5 Benzyl methacrylate Me ≠, jKg tacrylic acid copolymer (molar ratio near 2/core, intrinsic viscosity of methyl ketone solution of cozchc: θ・l-2Cp garden) Pentaerythritol tetraa j, jrKg acrylate Michler Ketone θ, /jK4ko,
λ'-bis(0-chlorof.,/jKgenyl)-
≠, Hiro 1'l'' 1-tetraphenylbiimidazo-z2/- monyl silicon dioxide 0,41, g
(W: CojJ, manufactured by Fuji Davison ■) Carbon dispersion liquid 211 to 4 The photosensitive resin-forming coating liquid prepared in this manner was applied to the surface of the support opposite to the back layer, and dried ( A photosensitive resin layer having a dry film thickness of 2.≠μm was provided at a drying temperature of /(700C) l and wound up.

The above wound raw ν is heated to a temperature of 2z0C and a humidity of jt% (
It was left in an atmosphere of RH for 1 week.

Separately, is there a coating liquid for forming a retention layer with the following composition? This coating solution was coated on the photosensitive resin layer and dried (drying temperature: 100° CA) to provide a protective layer with a dry thickness of i and z μm.

Coating liquid for protective layer Polyvinyl alcohol glue (GL
O! IN, manufactured by Nippon Gosei Kagaku Kogyo ■) Water
27Kg methanol jKfJJ - Aerosil R-97no 0. Rini 9 (Silica surface treated with dimethyldichlorosilane) In this way, 1. An image forming material consisting of a pack layer, a support, a photosensitive resin layer and a protective layer is manufactured in this order, and sample
And so.

[Comparative example/]

In Example 1, the same amount of Aerosil 200 (silica particles without surface treatment) was used in place of Aerosil R-27,2 in the protective layer. Except for this, an image forming material was produced by performing the same operations as in Example 1 and designated as Sample 2.

[Comparative example λ]

In Example 1, the protective layer Aerosil R-272 was removed, and the same procedure as in Example 2 was carried out except for this to produce an image forming material, which was designated as sample 2.

[Evaluation of image forming materials]

For each of the obtained image forming materials, the pack layer and the protective layer were stacked so that they overlapped (4to0c70%R).
The cells were left under 'I conditions for 3 days to examine the state of adhesion and reticulation. The sample size is rnn×r
crn, two weights were used as the load, and the number of samples was j.

The results obtained are shown in Table 1.

Table 1 Example 1 IO section Non-comparative example 1
II jO Section Comparative Examples 11
As is clear from the results shown in Table 1, the image forming material (Example 1) containing silica particles on the top layer that has been subjected to a hydrophobic surface treatment as shown in the present invention has no adhesive properties. No reticulation occurred either.

Further, this material had no spiders 9 or stains on the surface, and had a clean surface as an image forming material.

Claims (1)

[Claims] An image forming material comprising a photosensitive resin layer provided on a support, wherein the uppermost layer on the side of the photosensitive resin layer contains silica particles subjected to a hydrophobic surface treatment.