JPS62260143A - Image forming material - Google Patents

Abstract

PURPOSE:To prevent change of adhesion between the surface layer of a photopolymerizable composition layer and a metal base surface accompanied by the mutual action of both by using as a film forming polymer, 3 kinds of polymers together with a specified polymethyl (meth)acrylate incompatible with them. CONSTITUTION:The photopolymerizable composition layer of the image forming material comprises the film forming polymers composed essentially of (a) a polymer soluble or swellable in an aqueous solution of alkali, (b) polymethyl (meth)acrylate, (c) a halogenated polymer, and further, (d) poly(2-8C)alkyl (meth)acrylate; a photopolymerizable unsaturated compound; and a photopolymerization initiator. The surface layer of said photopolymerizable composition layer is made of the component (d) low in mutual activity to the metal base, thus permitting no change of adhesion between the surface layer and the metal base to be found even when they are held in contact for a long time.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an image forming material used for manufacturing printed wiring boards and the like.

[Conventional technology]

Conventionally, a photopolymerizable composition layer is provided on a transparent support, and the photopolymerizable composition layer is laminated on a metal substrate on which a circuit is to be formed so that it becomes the contact surface, and then patterned exposure is performed. By peeling off the transparent support, the unexposed portion of the photopolymerizable composition layer is peeled off together with the support, and the exposed portion remains on the substrate to form a predetermined resist pattern. Various image forming materials made of film resists have been proposed.

[Problem that the invention seeks to solve]

In forming a printed circuit using such an image-forming material, the standing time from when the material is laminated on a metal substrate with the photopolymerizable composition layer as the contact surface until patterned exposure is performed. is not necessarily constant. If this standing time becomes longer, since the composition layer is in contact with the metal substrate, some kind of interaction will occur between this layer and the active metal surface, which will affect the visibility of the layer. This may cause problems.

In particular, in the case where a film-forming polymer, which is one of the constituent components of the above layer, uses a polymer containing a polar group to impart water solubility or swelling properties to an alkaline aqueous solution, this type of layer may be made of metal. Because this layer is easily affected by secondary crosslinking due to the interaction between the surface and the above polar groups, a clear resist pattern can be obtained immediately after laminating this layer in contact with a metal substrate, but the pattern after lamination is There has been a problem that the longer the exposure time is, the stronger the adhesive force between the metal substrate surface and the photopolymerizable composition layer becomes, making it impossible to obtain a desired image.

Therefore, the present invention is capable of peeling off the photopolymerizable composition layer after exposure without being influenced by the length of time the photopolymerizable composition layer is left on the metal substrate to form a contact surface and then exposing the photopolymerizable composition layer to patterned light. An alkaline aqueous solution that can stably form a clear resist pattern on the substrate by developing it, and also causes fewer public health problems and increased costs than organic solvents when removing the resist. The purpose of the present invention is to provide an imaging material that can be applied.

[Means for solving problems]

As a result of intensive studies to achieve the above object, the inventors have determined that the support of an image forming material consisting essentially of a transparent support and a photopolymerizable composition layer is composed of a polyethylene terephthalate film; The above photopolymerizable composition layer is made of a film-forming polymer that is one of the constituent components of the photopolymerizable composition layer, which is a polymer that is soluble or swellable in an alkaline aqueous solution.
Methyl (meth)acrylate, halogen-containing polymers, and alkyl groups incompatible with these polymers have 2 or more carbon atoms.
When a structure containing eight poly(meth)acrylic acid alkyl esters is used as an essential component, this material is laminated on the surface of a metal substrate so that the photopolymerizable composition layer becomes the contact surface. Stable and good peeling development is always obtained, almost unaffected by the standing time before patterned exposure, and the final removal of the resist pattern formed on the substrate by peeling development is possible with alkali. It was discovered that an image forming material that can be easily formed using an aqueous solution was obtained, and this invention was completed.

That is, the present invention provides II & 1, which is a developable dry film resist, in which a photopolymerizable composition layer containing a film-forming polymer, a photopolymerizable unsaturated compound, and a photopolymerization initiator is provided on a transparent support. In the imaging material, the transparent support comprises a polyethylene terephthalate film, and the film-forming polymer comprises a)
a polymer soluble or swellable in an alkaline aqueous solution; b
) methyl poly(meth)acrylate, C) a halogen-containing polymer, and d) an alkyl poly(meth)acrylate whose alkyl group has 2 to 8 carbon atoms and is incompatible with the polymer of components a to c above. The present invention relates to an image forming material characterized by containing an ester as an essential component.

[Structure and operation of the invention]

The photopolymerizable composition layer in the image forming material of this invention is
The film-forming polymer contains a film-forming polymer, a photopolymerizable unsaturated compound, and a photopolymerization initiator;
Contains as essential components poly(meth)methyl acrylate, C) halogen-containing polymer, and d) poly(meth)acrylic acid alkyl ester having an alkyl group of 2 to 8 carbon atoms. It is a feature.

That is, the photopolymerizable composition layer of the present invention contains, as one component of the film-forming polymer, a carbon alkyl group that is incompatible with the d component, that is, the a''-c components that are essential components other than the d component. Poly (meta) with numbers 2 to 8
Since it contains an acrylic acid alkyl ester, when this layer is formed on a transparent support made of a polyethylene terephthalate film, the above-mentioned component d alone is added to the surface of the layer, that is, the surface opposite to the surface that contacts the transparent support. A thin film-like surface layer is formed, and this surface layer comes into contact with the surface of the metal substrate during circuit formation.

Here, the surface layer has low interaction with the metal substrate.
Since the photopolymerizable composition layer is made of a component polymer, even if the above-mentioned contact state is maintained for a long time, the adhesive force between the photopolymerizable composition layer and the transparent support does not change at all. Moreover, the above-mentioned surface layer also acts as a barrier layer to prevent the metal substrate from coming into contact with other film-forming polymers, especially the a-component polymer having a polar group such as a carboxyl group in the molecule. This results in good results in maintaining adhesive strength.

As described above, in the present invention, in addition to the above-mentioned a''-C component polymer used as a film-forming polymer to obtain good results in terms of peel developability and film strength, the d component which is incompatible with these components is used as a film-forming polymer. By using a specific poly(meth)acrylic acid alkyl ester, it is possible to prevent changes in the adhesive strength between the photopolymerizable composition layer and the metal substrate surface due to interaction with the metal substrate surface, and to improve printed circuit boards. The manufacturing latitude is wide (so that the desired image fidelity can always be obtained. Furthermore, by using a polymer that is soluble or swellable in an alkaline aqueous solution as the component a, it is easy to remove the patterned resist. It has the advantage of being able to apply an alkaline aqueous solution, and also has the characteristic of having excellent original peeling and developing properties.

The alkali aqueous solution-soluble or swellable polymer used as component a in this invention effectively contributes as a component for imparting alkaline aqueous solution-soluble or swellable properties to the photopolymerizable composition layer after exposure and curing. It is a thing,
Its average molecular weight is usually 1,000 or more, preferably 10,
000 to about 300,000 is used.

Such polymers that are soluble or swellable in alkaline aqueous solutions include homopolymers of acrylic acid or methacrylic acid, or monopolymers of these unsaturated polymers and alkyl acrylates, alkyl methacrylates, acrylamide, acrylonitrile, styrene, etc. copolymers with other monomers, or copolymers of maleic anhydride, maleic acid, maleic acid half esters, etc. with other monomers such as styrene, acrylic acid alkyl esters, methacrylic acid alkyl esters, butadiene, etc. There is such a thing as merging.

Methyl poly(meth)acrylate as component b increases the mutual solubility of the film-forming polymer and the photopolymerizable unsaturated compound, and prevents phase separation of the unsaturated compound within the photopolymerizable composition layer. By preventing this, it not only contributes as a component that brings good results to peeling and developability, but also increases the mechanical strength of the photopolymerizable composition layer, that is, the resist pattern, after exposure and curing, and greatly increases the resistance to etching solutions and plating solutions. It also contributes as a component. The average molecular weight of component b is usually 10.000 or more, preferably 100,000 to 100,000.
It is preferable that it be about 300,000.

The halogen-containing polymer as component C increases the adhesive strength between the polyethylene terephthalate film, which is a transparent support, and the photopolymerizable composition layer, and removes the unexposed portion of the photopolymerizable composition layer from the surface of the metal substrate together with the transparent support. It is effective in peeling off in a pattern and is effective in forming a clear pattern. Examples include polyvinyl chloride, polychloroprene, polychlorobutadiene, etc., as well as chlorinated polyolefins such as chlorinated polyethylene, chlorinated polypropylene, and chlorinated polyisoprene.

As mentioned above, the poly(meth)acrylic acid alkyl ester as the d component is incompatible with the above a''-C component, especially the b component, so that the photopolymerizable composition layer is not compatible with the contact surface. This polymer contributes as an effective component to obtain stable and clear images without being affected by the standing time from when it is laminated to a metal substrate until pattern exposure is performed.The average molecular weight of this polymer is Usually 1.ooo or more, preferably io,ooo to about 30,000 is used.

Even if the polymer as the above d component is a homopolymer of an alkyl acrylate ester having an alkyl group having 2 to 8 carbon atoms, the polymer may be a homopolymer of an alkyl methacrylate ester having an alkyl group having 2 to 8 carbon atoms. It may be a combination or a copolymer of both monomers. In particular, homopolymers of the former two are preferably used. Typical examples thereof include poly n-butyl methacrylate, poly n-propyl methacrylate, poly n-butyl acrylate, and poly n-propyl acrylate.

The ratio of each of these polymers constituting the film-forming polymer is 20 to 80% by weight, preferably 30 to 60% by weight of a polymer soluble or swellable in an alkaline aqueous solution as component C, and preferably 30 to 60% by weight of polymer as component B. Methyl (meth)acrylate is 20 to 80% by weight, preferably 30 to 60%
Weight%, halogen-containing polymer as component C is 10 to 5
0% by weight, preferably 15 to 30% by weight, and 0.5 to 5% by weight, preferably 1% by weight of a poly(meth)acrylic acid alkyl ester whose alkyl group has 2 to 8 carbon atoms as component d. It is preferable to adjust the amount to 3% by weight.

By using the proportions shown above, good results can be obtained in terms of image fidelity, peeling and developing properties, and resist removability with an alkaline aqueous solution. In particular, it is best to use a small amount of the d component compared to other components; if the d component is too large, the adhesion between the photopolymerizable composition layer and the metal substrate surface in the exposed area will be weakened. This is not preferable because it may cause peeling of the exposed pattern.

In addition, as the film-forming polymer, the above-mentioned a.

In addition to components b, c, and d as essential components, other polymers may be used in combination as necessary within a range that does not impair the characteristics of the present invention.

In this invention, the photopolymerizable unsaturated compound, which is one of the components constituting the photopolymerizable composition layer, includes monoethylenically unsaturated compounds having one ethylenically unsaturated bond in the molecule and polyethylene having two or more ethylenically unsaturated bonds. and sexually unsaturated compounds. Particularly preferably, a polyethylenically unsaturated compound is used alone or in a mixed system with a monoethylenically unsaturated compound.

Examples of monoethylenically unsaturated compounds include acrylic acid or its esters, methacrylic acid or its esters, acrylamides, methacrylamides, allyl compounds, vinyl ethers, vinyl esters, N-vinyl compounds, styrenes, These include crotonic acid esters.

Specific examples of acrylic esters include propyl acrylate, butyl acrylate, amyl acrylate,
2-ethylhexyl acrylate, octyl acrylate, etc.; methacrylate esters include methyl methacrylate, ethyl methacrylate, propyl methacrylate, isopropyl methacrylate, etc.; acrylamides include acrylamide, N-alkyl group is methyl group, ethyl group, etc. basis,
Butyl group, isopropyl group, tert-butyl group, 2-
N-alkylacrylamide, which consists of an ethylhexyl group, etc., and methacrylamide, where the N-alkyl group is a methyl group, ethyl group, isopropyl group, tert-'7'th)L4.2-ethylhexyl group, etc. N-alkyl methacrylamide, etc.

In addition, allyl compounds include allyl esters such as allyl acetate, allyl caproate, allyl caprylate, allyl laurate, and allyl palmitate, and the vinyl ethers include hexyl vinyl ether, octyl vinyl ether,
Alkyl vinyl ethers such as decyl vinyl ether and 2-ethylhexyl vinyl ether are used as vinyl esters such as vinyl butyrate, vinyl isobutyrate, vinyl trimethyl acetate, vinyl diethyl acetate-1-
, vinyl valerate, vinyl caproate, etc.
Vinyl compounds include N-vinylpyrrolidone, styrenes include styrene, methylstyrene, chloromethylstyrene, alkoxystyrene, halogenated styrene, and styrene benzoate, and crotonate esters include methyl crotonate, ethyl crotonate, and crotonate. Examples include butyl, hexyl crotonate, and isopropyl crotonate.

Next, examples of polyethylenically unsaturated compounds include polyacrylate-t[i, which is a polyhydric alcohol, and polymethacrylates. The above polyhydric alcohols include polyethylene glycol, polypropylene oxide,
Polybutylene oxide, (β-hydroxyethoxy)benzene, glycerin, diglycerin, neopentyl glycol, trimethylolpropane, trimethylolpropane, pentaerythritol, dipentaerythritol, sorbitan, sorbitol, l・4-butanediol, ■・2・4-butanetriol, 2-buteneto 4-
Diol, 2-butyl-2-ethyl-propanediol, 2-butenoto-4-diol, 1,3-propanediol, triethanolamine, decalindiol, 3-
Examples include chlorate 2-propanediol.

In addition, other examples of polyethylenically unsaturated compounds include:
There are acrylate oligomers and methacrylate oligomers having two or more acryloyl groups or methacryloyl groups in the molecule, which are commercially available under the names of oligoester acrylate, oligoester methacrylate, epoxy acrylate, epoxy methacrylate, urethane acrylate, urethane methacrylate, etc.

In addition to the above-mentioned compounds, examples of photopolymerizable unsaturated compounds include monoesters of dicarboxylic acids such as succinic acid, maleic acid, phthalic acid, and hexahydrophthalic acid with 2-hydroxyethyl acrylate or methacrylate. An unsaturated compound having a carboxyl group is effective. That is, the use of this type of compound is preferable because good results can be obtained due to the dissolution and removability of the cured resist with an alkaline aqueous solution.

Such photopolymerizable unsaturated compounds are generally used in an amount of 10 to 500 parts by weight, preferably 30 to 200 parts by weight, based on 100 parts by weight of the film-forming polymer.

If this amount is too small, the photopolymerizability, that is, the exposure curing property will be poor, and if it is too large, the peeling performance will be poor, and in either case, the ff1ll 1W1f developability is likely to be impaired. Also, if this photopolymerizable unsaturated compound becomes too large,
Unless an unsaturated compound having a carboxyl group in the molecule as described above is used, the solubility or swelling property in an alkaline aqueous solution after exposure and curing may decrease, causing problems in resist removability.

In this invention, the photopolymerization initiator, which is another component constituting the photopolymerizable composition layer, includes a wide range of conventionally known initiators. Specific examples include carbonyl compounds, organic sulfur compounds, peroxides, redox compounds, azo and diazo compounds, and photoreducible dyes.

Examples of the above carbonyl compounds include benzoin, benzophenone, anthraquinone, 2-methylanthraquinone, 2-tert-butylanthraquinone, 9,10-phenanthrenequinone, diacetyl, benzyl, Michler's ketone, 4,4'-bisdiethylaminobenzophenone, etc. Examples of the sulfur compound include dibutyl disulfide, dioctyl disulfide, dibenzyl disulfide, diphenyl disulfide, dibenzoyl disulfide, and diacetyl disulfide.

In addition, as peroxides, hydrogen peroxide, g-tert-
Butyl peroxide, benzoyl peroxide, methyl ethyl ketone peroxide, etc. are used as redox compounds. Diferric ions and peroxides are used as ab and diazo compounds such as α・α′-azobisisobutyronitrile, 2-azobis-2-methylbutyronitrile, l
Examples of photoreducible dyes include rose bengal, erythrosin, eosin, acriflavin, riboflavin, and thionin.

These photopolymerization initiators may be used alone or in combination of two or more. The amount used is usually in the range of 0.1 to 20 parts by weight per 100 parts by weight of the photopolymerizable unsaturated compound.

The photopolymerizable composition layer of the present invention contains the above-mentioned film-forming polymer, photopolymerizable unsaturated compound, and photopolymerization initiator as essential components. Various additives such as inhibitors, colorants, adhesion improvers, fillers, and plasticizers may be included.

In the present invention, such a photopolymerizable composition layer is obtained by uniformly dissolving and dispersing each of the above components in a solvent, and depositing this on a transparent support with a thickness of 5 to 100 μm, preferably 5 to 100 μm after drying.
It is formed by coating to a thickness of 50 μm and drying.

As the above-mentioned solvent, ketones such as acetone, methyl ethyl ketone, and methyl isobutyl ketone, and esters such as ethyl acetate, butyl acetate, and amyl acetate are preferably used. In addition, aromatic hydrocarbons such as toluene, benzene, and xylene, halogenated hydrocarbons such as carbon tetrachloride, chloroform, trichloroethylene, and methylene chloride, and alcohols such as methanol, ethanol, propatool, and butanol are also used in the form of mixed solvents. Can be used in

Moreover, the thickness of the above-mentioned transparent support is 10 to 50 μm.
A polyethylene terephthalate film having a thickness of about 100 m is used. This film has excellent adhesion to the photopolymerizable composition layer using the above-mentioned specific film-forming polymer, and has transparency to light in the wavelength range of 300 to 500 nm that can photopolymerize the photopolymerizable composition layer. Good and uniform surface,
Strength.

It also has excellent characteristics such as dimensional stability, heat resistance, and moisture absorption.

The image forming material of the present invention is composed of a peelable 41 developable dry film resist containing the transparent support obtained as described above and a photopolymerizable composition layer, and this material may be stored as required. In order to protect the photopolymerizable composition layer therein, a protective film made of polyethylene, polypropylene, or various plastic films subjected to release treatment may be provided on the composition layer.

Next, a method for forming a circuit using the image forming material of the present invention constructed as described above will be explained.

In this method, first, the surface of a board on which a circuit is to be formed, such as a hollow laminated board for obtaining a printed wiring board, is cleaned, and Ii? If the image forming material of the present invention having the structure described in f has a protective film, the protective film is peeled off, and then the image forming material is pressure-bonded to a substrate so that the photopolymerizable composition layer side becomes the contact surface. The pressure bonding temperature at this time is usually about 20 to 80°C.

Next, for example, a negative mask having a circuit pattern is placed on the transparent support and exposed to light from a light source containing light with a wavelength of 300 to 500 nm, such as a high-pressure mercury lamp, an ultra-high-pressure mercury lamp, a xenon lamp, a carbon arc lamp, or the like.

After being exposed in this way, the substrate is preferably
When the transparent support is peeled off from the substrate while kept at a temperature of °C, the photopolymerizable composition layer in the exposed areas in pattern exposure is photocured and remains on the substrate, while the unexposed areas remain uncured and transparent. It is peeled off together with the support, thereby forming a desired resist pattern on the substrate. here,
Peeling and removal of the non-exposed portions is not particularly affected by the length of time the product is left to stand after being crimped onto the substrate and before the pattern exposure is performed.In other words, it can be carried out well even if the time for which it is left to stand is extremely long. can.

Therefore, the exposed surface of the substrate without resist, or in the case of a printed wiring board, the copper surface without resist, is etched using an etching solution such as ferric chloride solution or cupric chloride solution. Then, by immersing it in an alkaline aqueous solution such as sodium hydroxide or potassium hydroxide containing about 3 to 8% by weight, preferably at a temperature of 40 to 80''C, or by spraying such an alkaline aqueous solution, The hardened resist dissolves or swells and is peeled off from the substrate.Then, the resist is thoroughly washed with water and dried to obtain a positive image circuit pattern etched on the substrate.

In addition, when a positive mask is used instead of a negative mask in the above method, after forming a resist pattern in the same manner as above, copper, solder, gold, etc. are applied to the substrate surface that does not have a resist instead of etching. By performing plating treatment and then removing the resist using an alkaline aqueous solution in the same manner as described above, a positive image circuit pattern plated on the substrate can be obtained.

〔Effect of the invention〕

As described above, in this invention, the transparent support in the peel-and-developable dry film resist is composed of a polyethylene terephthalate film, while the photopolymerizable composition layer contains a polyethylene terephthalate film having an alkyl group of 2 to 8 carbon atoms. (meta)
Because it contains an acrylic acid alkyl ester as an essential component, the photopolymerizable composition layer was left to stand for a long time immediately after lamination, regardless of the time it was left before pattern exposure after lamination on the metal substrate surface as the contact surface. It is possible to carry out stable peeling development, which means that excellent image fidelity can be obtained, and because one of the film-forming polymers used is one that is soluble or swellable in alkaline aqueous solutions, An advantage can be obtained that the hardened resist can be removed after the necessary circuit formation processing using an alkaline aqueous solution, which is cheaper and less of a public health problem than organic solvents.

〔Example〕

EXAMPLES Below, examples of the present invention will be described in more detail. In addition, in the following, parts shall mean parts by weight.

Example 1 Polymer n-butyl methacrylate 2 parts Benzophenone 6 parts 4,4'-bisdiethylaminohenzo 1 part Phenone tribromomethyl phenyl sulfone 1 part Paramethoxyphenol 0.1 part Victoria Pure Blue 0.2 part Ethyl acetate
A solution of the photopolymerizable composition was prepared by uniformly dissolving and mixing 300 parts of the above materials. Spread this liquid to a thickness of 2
It was coated on a 5 μm polyethylene terephthalate film to a dry thickness of 25 μm, and then heated at 80°C.
By carrying out a drying treatment for 5 minutes, an image forming material consisting of a peelable and developable dry film resist was obtained.

This image forming material was applied to the copper-clad surface of 82 copper-clad glass-epoxy laminated N substrates with clean surfaces at a temperature of 50°C, with the photopolymerizable composition layer side facing each other. Immediately after that, a negative manuscript with a circuit pattern was brought into close contact with a transparent support made of the above material, and one sheet A was exposed to light for 10 seconds from a distance of 60 cm using a 3KW ultra-high pressure mercury lamp. Ta. Another sheet B was left at room temperature for 1 hour and then exposed to light using the above method.

Next, when the substrate temperature of each of A and B is set to 30°C and the polyethylene terephthalate film, which is the transparent support of the image forming material, is peeled off from the substrate, the non-exposed portions of both A and B are peeled off and removed from the substrate. A resist pattern was formed in which only the exposed portion remained on the substrate and constituted a good positive circuit.

Next, the copper-clad substrate having the resist patterns A and B thus obtained was etched with a ferric chloride aqueous solution at 40 degrees Baumé to remove the exposed copper foil. After that, sodium hydroxide solution with a concentration of 3% by weight? When immersed in liquid g (liquid temperature 50"C) for 5 minutes, A
The cured resists in both cases swelled and peeled off from the substrate. A desired printed wiring board was obtained by washing these substrates with water and drying them.

Example 2 In the photopolymerizable composition shown in Example 1, 45 parts of a copolymer of styrene and n-butyl cellosolve maleate half ester, 38 parts of polymethyl methacrylate, and a halogen-containing polymer were added. Except for changing each to 15 parts,
An image forming material was produced in the same manner as in Example 1. Next, using this material, circuits were formed on 82 boards A in the same manner as in Example 1, and as in Example 1, printed wiring boards having the desired circuit pattern were obtained on both boards. I was able to do that. Note that removal of the patterned resist using an alkaline aqueous solution in the circuit forming process was easy as in Example 1.

In addition, in the above photopolymerizable composition, 30 parts of polymethyl methacrylate and 10 parts of polyn-butyl methacrylate were used.
An image-forming material was obtained in the same manner as above, with the respective changes made, and circuit formation was attempted from this in the same manner as above.
For both substrates A and B, both the unexposed portion and the exposed portion were peeled off from the surface of the substrate during peeling and development, making it impossible to form a patterned resist on the substrate.

Comparative Example 1 The same procedure as in Example 1 was carried out except that in the photopolymerizable composition shown in Example 1, the halogen-containing polymer was changed to 20 parts, and polyn-butyl methacrylate was not used. An image forming material was prepared.

Next, A and 8 were prepared in the same manner as in Example 1 using this material.
When circuits were formed on two substrates, A, in which pattern exposure was performed immediately after lamination, was able to form a good positive circuit, whereas in B, in which pattern exposure was performed after standing, the non-exposed portions peeled off and developed. At times, the image was transferred from the support onto the substrate, resulting in a significant decrease in image quality.

Example 3 Polyisopropyl methacrylate 2 parts diethylthioxanthone 3 parts isoamyl dimethylaminobenzoate 2 parts para-toluenesulfonyl chloride 1 part hydroquinone 0.
1 part Crystal violet 0.3 parts Methyl ethyl ketone 300 parts An image forming material was prepared in the same manner as in Example 1 using the solution of the above photopolymerizable composition. A. After forming circuits on 82 boards, A.B
In both cases, a printed wiring board having the same desired circuit pattern as in Example 1 could be obtained.

Example 4 n-butyl polyacrylate 5 parts diethylthioxanthone 3 parts isoamyl dimethylaminobenzoate 2 parts tribromomethylphenylsulfone 1 part paramethoxyphenol
0.1 part crystal violet 0.
3 parts Methyl ethyl ketone 300 parts An image forming material was prepared in the same manner as in Example 1 using the solution of the above photopolymerizable composition, and using this material, 32 substrates A and I were prepared in the same manner as in Example 1. When circuit formation was carried out, printed wiring boards having the same desired circuit patterns as in Example 1 were obtained for both A and B.

Comparative Example 2 Copolymer of monobutyl and methyl methacrylate (molar ratio 5
:5) An image forming material was obtained in the same manner as in Example 4 except that the amount was changed to 5 parts, and A was prepared in the same manner as in Example 4 using this material.
When circuits were formed on 32 substrates, A, in which pattern exposure was performed immediately after lamination, was able to form the desired positive image circuit, whereas B, in which pattern exposure was performed after standing, was not exposed during peeling and development. A portion was slightly transferred onto the substrate from the support, and a clear image could not be obtained.

Claims (1)

[Claims] (1) In an image forming material consisting of a peelable and developable dry film resist, which is formed by providing a photopolymerizable composition layer containing a film-forming polymer, a photopolymerizable unsaturated compound, and a photopolymerization initiator on a transparent support, The transparent support is composed of a polyethylene terephthalate film, and the film-forming polymer is a) a polymer soluble or swellable in an alkaline aqueous solution, b) poly(meth)methylacrylate, and c) a halogen-containing polymer. and d) above a to c
An image forming material comprising as an essential component a poly(meth)acrylic acid alkyl ester having an alkyl group having 2 to 8 carbon atoms, which is incompatible with the component polymer.