JPS6410056B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an image forming material, and more specifically, it has a photosensitive layer on a transparent support, and after exposure, heating if necessary, and then peeling off the support. The present invention relates to a peel-developable image-forming material from which an image can be obtained.

Conventionally, solution-type photoresists and film-type photoresists have been commercially available for producing printed wiring boards, but these utilize the difference in solubility of exposed and unexposed areas in a solution to form an image. It forms the

However, in recent years, the operation of using a developer has become complicated, and the use of a developer has the potential to cause waste fluid to harm public health.
No. 38-9663, Special Publication No. 1972-22901, Japanese Patent Publication No. 1973-
No. 7728, Japanese Patent Publication No. 48-43126, Japanese Patent Publication No. 47-33623
Peelable and developable image forming materials and image forming methods as described in Japanese Patent Publication No. 51-48516, Japanese Patent Publication No. 40537, Japanese Patent Publication No. 53-19205, and Japanese Patent Publication No. 53-35722. is proposed.

These methods utilize the difference in adhesion between the exposed and unexposed areas to the base material and the support to form an image by peeling. Although it is possible to obtain a somewhat satisfactory image with a relatively thin photosensitive layer that is prone to breakage, for example, in the case of etching resist applications (referred to as tenting resists) used when etching through-hole copper substrates, through-hole areas are Because it needs to be able to withstand the spray pressure of the etching solution,
The resist film that covers the through-hole portion must have sufficient film strength, and the resist film must be thick to some extent, but tenting resist requires a relatively thick photosensitive layer. At present, a product that is satisfactory for use has not yet been obtained.

When etching a through-hole copper board,
Since it is necessary to withstand the spray pressure of the etching solution, the resist film covering the through-hole portion must have strength and elongation.

Now, image forming materials that can be developed with organic solvents or alkaline aqueous solutions use a method in which the portions that are hardened by exposure remain on the base material and the unexposed portions are dissolved and removed by the developer. The adhesive force between the photopolymerizable composition layer and the base material can be made sufficiently large in advance, and there is little problem with peeling of exposed areas during development. However, in the image-forming material that forms an image by peeling, which is the subject of the present invention, it is necessary to easily peel off the unexposed areas, so the adhesive force between the photosensitive layer and the base material must be made sufficiently large in advance. I can't. Therefore, only the exposed areas are required to have very high practical adhesion to the substrate (adhesion that can resist peeling, tension, shear scratching, etc.).

Particularly when used as a tenting resist, it is necessary to increase the film thickness of the photosensitive layer to provide film strength. At the same time, a large force is applied during peeling, so even if the exposed portion has a certain degree of adhesion to the substrate, the exposed portion tends to peel off during peeling, such as when the adhesive area with the substrate is small.

In particular, photosensitive layers that have been made to have extremely good elongation in order to obtain a strong film tend to have a relatively small modulus of elasticity in the exposed areas, and when the unexposed areas are peeled off together with the support. The exposed areas tended to be easily deformed and peeled off.

The object of the present invention is to provide an etching resist in which the resist film covering the through-hole portion has excellent elongation so as to sufficiently withstand the spray pressure of the etching solution, and the photosensitive layer in the unexposed portion can be easily peeled off. Another object of the present invention is to provide an image-forming material that can be peeled and developed, and has excellent adhesion that does not peel off even in exposed areas with a very small adhesion area during peeling and development.

The present inventors have made extensive studies to overcome the shortcomings of the prior art in accordance with the above-mentioned objectives, and have developed a compound having a film-forming polymeric substance and at least one addition-polymerizable unsaturated bond on a transparent support. In an image forming material constructed by providing a photosensitive layer containing a photopolymerization initiator as an essential component, the general formula (However, m+n=3, n is 1 or 2, X is a hydrogen atom or CH ₃ group, and R is an alkylene group) By incorporating a compound represented by the following into the photosensitive layer, extremely excellent adhesion (i.e. The inventors discovered that this can be used as an image-forming material (the exposed portion is difficult to peel off from the substrate during peel development), leading to the present invention.

Examples of the compound represented by the general formula (A) used in the present invention include 2-hydroxyethyl acryloyl phosphate, 2-hydroxyethyl methacryloyl phosphate, bis-(2-hydroxyethyl acryloyl) phosphate, and bis-(2-hydroxyethyl acryloyl) phosphate.
-hydroxyethyl methacryloyl) phosphate, 2-hydroxypropyl acryloyl phosphate, 2-hydroxypropyl methacryloyl phosphate, bis-(2-hydroxypropyl acryloyl) phosphate, bis-(2-hydroxypropyl methacryloyl) phosphate, and the like.

These compounds range from 0.01 to 10% based on the total photosensitive layer.
It can be used in a range of % by weight, more preferably in a range of 0.1 to 1% by weight. If it is less than 0.01% by weight, hardly any effect will be obtained, and if it is too much, such as 10% by weight or more, it may become more likely to peel off and no effect may be obtained.

To explain other materials constituting the image forming material of the present invention, the transparent support used in the present invention has a thickness of 300 to 500 nm capable of photopolymerizing the photosensitive layer.
It is necessary that the light transmittance in the wavelength range is good and the surface is uniform.

Specific examples of such supports include polyethylene terephthalate, polypropylene, polyethylene, cellulose triacetate, cellulose diacetate,
Polyvinyl chloride, polyvinyl alcohol, polycarbonate, polystyrene, cellophane, polyvinylidene chloride copolymer, polyamide (e.g. 6
Various types of plastic films can be used, such as polyimide, vinyl chloride-vinyl acetate copolymer, polytetrafluoroethylene, and polytrifluoroethylene. Furthermore, a composite material consisting of two or more of these types can also be used.

The support generally has a thickness of 10 to 150 μm, preferably 20 to 50 μm, but supports having a thickness outside the above range can also be used.

Film-forming polymeric substances that can be used in the present invention can be selected from a wide variety of polymeric substances, but those that have extremely poor compatibility with other constituents are not preferred.

Examples of preferred film-forming polymeric substances include:
Chlorinated polyolefins (e.g. chlorinated polyethylene, chlorinated polypropylene), polymethyl methacrylate, polymethyl acrylate, polyvinyl chloride, polyvinylidene chloride, polyvinyl butyral, polyvinyl acetate, vinyl chloride-vinyl acetate copolymer, vinylidene chloride-acrylonitrile Examples include copolymers, polyisoprene, chlorinated rubber, polychloroprene, polychlorosulfonated ethylene and polychlorosulfonated propylene, and solvent-soluble linear saturated polyesters. Two or more of these polymeric substances can be used in combination.

The compound having at least one addition-polymerizable unsaturated bond used in the present invention includes a wide range of addition-polymerizable compounds. Examples include acrylic esters, acrylamides, methacrylic esters, methacrylamides, allyl compounds, vinyl ethers, vinyl esters, N-vinyl compounds, styrenes, crotonic esters, and the like. Specific examples of compounds having one addition-polymerizable unsaturated bond include acrylic esters, such as acrylic acid, alkyl acrylates (such as propyl acrylate, butyl acrylate, amyl acrylate, ethylhexyl acrylate, octyl acrylate). ), methacrylic esters, such as methacrylic acid, alkyl methacrylates (such as methyl methacrylate, ethyl methacrylate, propyl methacrylate, isopropyl methacrylate),
Acrylamides, such as acrylamide, N-
alkylacrylamide, (acid alkyl groups include, for example, methyl, ethyl, butyl, isopropyl, t-butyl, ethylhexyl, etc.), methacrylamide, such as methacrylamide, N-alkylmethacrylamide ( Examples of the alkyl group include methyl group, ethyl group, isopropyl group, t-butyl group, and ethylhexyl group), allyl compounds such as allyl esters (such as allyl acetate, allyl caproate, allyl caprylate, and lauric acid) allyl, allyl balmitate), vinyl ethers such as alkyl vinyl ethers (e.g. hexyl vinyl ether, octyl vinyl ether, decyl vinyl ether, ethylhexyl vinyl ether),
Vinyl esters such as vinyl butyrate, vinyl trimethyl acetate, vinyl diethyl acetate, vinyl valerate, vinyl caproate, and the like. Other styrenes include styrene, methylstyrene, chloromethylstyrene, alkoxystyrene, halogenated styrene, and styrene benzoate. Examples of crotonate esters include methyl crotonate, ethyl crotonate, butyl crotonate, hexyl crotonate, and isopropyl crotonate.

Next, specific examples of compounds having two or more addition-polymerizable unsaturated bonds are illustrated, and these are more preferably used than the above-mentioned compounds having one addition-polymerizable unsaturated bond. First, acrylic esters and methacrylic esters include polyacrylates and polymethacrylates (herein, "poly" refers to diacrylate or higher) of polyhydric alcohols. The polyhydric alcohol mentioned above is
Polyethylene glycol, polypropylene oxide, polybutylene oxide, (β-hydroxyethoxy)benzene, glycerin, diglycerin,
Neopentyl glycol, trimethylolpropane, triethylolpropane, pentaerythritol, dipentaerythritol, sorbitan, solpitol, 1,4-butanediol, 1,2,
4-butanetriol, 2-butene-1,4-diol, 2-butyl-2-ethyl-propanediol, 2-butene-1,4-diol, 1,3-
Examples include propanediol, triethanolamine, decalindiol, 3-chloro-1,2-propanediol, and the like.

In addition, oligoester acrylate, oligoester methacrylate, epoxy acrylate,
Acrylates and methacrylates commercially available under names such as urethane acrylate can also be suitably used.

Two or more kinds of such compounds having at least one addition-polymerizable unsaturated bond can also be used in combination. These compounds are film-forming polymeric substances.
It is used in an amount of 10 to 500 parts by weight, preferably 30 to 200 parts by weight per 100 parts by weight.

As the photopolymerization initiator used in the present invention, conventionally known ones can be suitably used, and these include carbonyl compounds, organic sulfur compounds, peroxides, redox compounds, azo and diazo compounds, halogen compounds, There are photoreducible dyes. Typical specific examples of carbonyl compounds include benzoin, benzoin methyl ether, benzoin isopropyl ether, benzoin isobutyl ether, benzyl dimethyl ketal, benzophenone, anthraquinone,
-methylanthraquinone, 2-t-butylanthraquinone, 9,10-phenanthrenequinone, diacetyl, benzyl and the like.

Examples of organic sulfur compounds include dibutyl disulfide, dioctyl disulfide, dibenzyl disulfide, diphenyl disulfide, dibenzoyl sulfide, and diacetyl disulfide.

Examples of peroxides include hydrogen peroxide, di-t-butyl peroxide, benzoyl peroxide, and methyl ethyl ketone peroxide.

Redox compounds consist of a combination of a peroxide and a reducing agent, and include ferrous ions and hydrogen peroxide, ferrous ions and persulfate ions, ferric ions and peroxides, and the like.

Examples of azo and diazo compounds include a,a'-azobisisobutyronitrile, 2-azobis-2-methylbutyronitrile, 1-azo-bis-cyclohexanecarbonitrile, and diazonium salt of P-aminodiphenylamine. There is.

Examples of the halogen compound include chloromethylnaphthyl chloride, phenacyl chloride, chloroacetone, β-naphthalenesulfonyl chloride, and xylene sulfonyl chloride.

Photoreducible pigments include rose bengal, erythrosin, eosin, acriflavin, riboflavin, and thionin.

These photopolymerization initiators can be used alone or in combination of two or more types as required.

These photopolymerization initiators can be used generally in an amount of 0.1 to 20 parts by weight per 100 parts by weight of the unsaturated compound.

The photosensitive layer of the image-forming material of the present invention is composed of the film-forming polymer substance, addition polymerizable unsaturated bond, photopolymerization initiator, and specific adhesion improver as described above. Depending on the requirements, various additives such as thermal polymerization inhibitors, colorants, fillers, and plasticizers can also be included.

Each component forming the photosensitive layer used in the present invention is dissolved in a solvent to form a coating solution, which is coated on a support and dried.

Solvents for the coating solution include ketones such as acetone, methyl ethyl ketone, and methyl isobutyl ketone, aromatic hydrocarbons such as toluene, benzene, and xylene, esters such as ethyl acetate, butyl acetate, and amyl acetate, carbon tetrachloride, chloroform,
Examples include halogenated hydrocarbons such as trichloroethylene and methylene chloride, ethers such as diethyl ether, tetrahydrofuran, dioxane, and ethylene glycol monomethyl ether, dimethylformamide, and dimethyl sulfoxide.

The photosensitive layer is provided so that the coating solution is applied onto the support and the thickness after drying is 5 to 100 .mu.m, preferably 10 to 60 .mu.m. The image forming material of the present invention has a structure in which a photosensitive layer is provided on a support, but a protective film can also be provided on the photosensitive layer if necessary. As the protective film, polyethylene, polypropylene, various films treated with non-adhesive treatment, paper, etc. can be used.

To explain the method of forming an image using the image forming material of the present invention, if the image forming material of the present invention has a protective film, the protective film is peeled off and then the photosensitive layer is pressure-bonded to a desired substrate.
The image is then exposed through the transparent support.

As the light source, a light source containing light with a wavelength in the range of 350 to 500 nm, such as a high-pressure mercury lamp, an ultra-high-pressure mercury lamp, a xenon lamp, a carbon arc lamp, etc., can be used. In addition, laser beams, electron beams, X-rays, etc. may be used as the light source. If necessary, heat treatment may be applied after image exposure (50℃ to 120℃).
(about 1 minute to 120 minutes), when the support is peeled off from the substrate, the exposed part in the image exposure is cured and remains on the substrate, and the unexposed part is removed together with the support without being cured, thus forming the desired image on the substrate. It is formed.

When the image-forming material of the present invention is used as a so-called tenting resist with a thick photosensitive layer, the cured portion has good adhesion to the base material, so it can be conveniently used to produce images without defects due to peeling. However, of course, it can also be suitably used for producing other resist images not intended for tenting.

Furthermore, it can be used for purposes such as the production of printing plates for lithographic printing, letterpress printing, etc., and the production of other relief images.

The present invention will be specifically explained below using examples, but the present invention is not limited to these examples.

Example 1 Chlorinated polyethylene (Superclone CPE907LTA manufactured by Sanyo Kokusaku Pulp Co., Ltd.) 70 (parts by weight) Polymethyl methacrylate (Dyanal BR-80 manufactured by Mitsubishi Rayon Co., Ltd.) 30 Pentaerythritol triacrylate 150 Benzoin isopropyl ether 7.5 2-Hydroxyethyl acryloyl phosphate
1.0 Ethyl violet 0.3 Paramethoxyphenol 0.1 Toluene 400 A photosensitive solution was prepared by uniformly dissolving and mixing the above materials.

This photosensitive solution is dried on a polyethylene terephthalate film with a thickness of 25 μm, and the thickness of the photosensitive layer is
An image forming material was prepared by coating the film to a thickness of 50 μm and drying at 80° C. for 15 minutes.

Next, this image forming material was laminated under pressure on both sides of a double-sided copper-clad substrate for a printed wiring board having through holes whose surface had been cleaned. In this state, the negative original with the wiring circuit pattern was brought into close contact with the support of the image forming material laminated on the copper surface, and the negative original was exposed for 20 seconds from a distance of 60 cm using a 3KW ultra-high pressure mercury lamp. (Both sides of the board are exposed).
Next, when the substrate is heated to 35°C and the polyethylene terephthalate film support is peeled off from the substrate, the exposed parts of the photosensitive layer harden and remain on the copper substrate, and the unexposed parts are covered with copper along with the support. After being removed from the substrate, a positive image corresponding to the negative original was formed on the copper substrate. The resist pattern formed in this way faithfully reproduced the negative original, and there was no defect such as the exposed portion peeling off from the substrate, resulting in disconnection or loss of the image, or the defect that the tenting portion was torn. .

Similar operations were performed on nine more substrates, and resist patterns with no defects were similarly obtained. The copper layer of the copper-clad substrate having the resist pattern thus obtained was etched at 40°C using an aqueous ferric chloride solution, but even during this etching process, the photosensitive layer remained resistant to copper. It was confirmed that no phenomena such as adhesion, peeling, or generation of pinholes occurred. Further, the photosensitive layer after etching could be easily peeled off from the substrate using methylene chloride.

Example 2 An image forming material was prepared in the same manner as in Example 1 except that 2-hydroxyethyl acryloyl phosphate was replaced with 2-hydroxyethyl methacryloyl phosphate.

Example 3 An image forming material was prepared in the same manner as in Example 1 except that 2-hydroxyethyl acryloyl phosphate was replaced with bis-(2-hydroxyethyl acryloyl) phosphate.

For Examples 2 and 3, the same image formation and etching processes as in Example 1 were performed, and the same good results as in Example 1 were obtained.

Comparative Example 1 An image forming material was prepared using the photosensitive solution of Example 1 without adding 2-hydroxyethyl acryloyl phosphate.

Comparative Example 2 In the photosensitive solution of Example 1, 2-hydroxyethyl acryloyl phosphate was replaced with tris-(2-
An image forming material was prepared in the same manner except that hydroxyethyl acryloyl) phosphate was used instead.

In the case of Comparative Examples 1 and 2, it was confirmed that in the obtained images, a connection failure due to peeling of the exposed portion occurred in about one out of every two substrates.

Example 4 Polymethyl methacrylate (Dyanal BR-75 manufactured by Mitsubishi Rayon Co., Ltd.) 90 (parts by weight) Chlorinated rubber (Super Chron manufactured by Sanyo Kokusaku Pulp Co., Ltd.)
CR-5) 10 Pentaerythritol triacrylate 50 Oligoester acrylate (Aronix M-6100 manufactured by Toagosei Chemical Industry Co., Ltd.) 100 Benzoin isopropyl ether 10 2-Hydroxyethyl acryloyl phosphate
2 Paramethoxyphenol 0.1 Ethyl violet 0.3 Toluene 400 A photosensitive solution was prepared by uniformly dissolving and mixing the above materials.

This photosensitive solution was applied onto a polyethylene terephthalate film having a thickness of 25 μm so that the thickness after drying would be 50 μm, and the film was dried at 80° C. for 15 minutes to prepare an image forming material.

Thereafter, exposure was carried out in the same manner as in Example 1, and after exposure, the substrate was heat-treated at 80° C. for 30 minutes. After cooling this to room temperature (25°C), the support was peeled off from the substrate, and a resist pattern was obtained on the substrate. This resist pattern has no defects, and Example 1
Similarly, no defects were caused by etching treatment.

Comparative Example 3 Using the photosensitive liquid of Example 4 except for 2-hydroxyethyl acryloyl phosphate, Example 4 was prepared.
A similar evaluation was conducted. Due to peel development, the image had very noticeable defects due to peeling in exposed areas.

Claims (1)

[Scope of Claims] 1. An image formed by providing on a transparent support a photosensitive layer containing a film-forming polymeric substance, a compound having at least one addition-polymerizable unsaturated bond, and a photopolymerization initiator as essential components. In forming materials, the general formula is used as an adhesion improver. (However, m+n=3, n is 1 or 2, X is a hydrogen atom or CH ₃ group, and R is an alkylene group) is added to the photosensitive layer to form a peelable and developable image. material.