JPS63123038A - Image forming material - Google Patents

Abstract

PURPOSE:To improve the adhesion of a cured image to a substrate on which the image is formed, by forming an image forming photosensitive resin layer contg. a specified triphenylmethane compd. on a transparent support. CONSTITUTION:A photosensitive resin layer contg. a compd. represented by formula I is formed on a transparent support and the unexposed part of the resin layer is removed by development with an alkaline aq. soln. The resin layer is made of a compsn. consisting of a film forming polymer, an ethylenic unsatd. polymerizable compd., a photopolymn. initiator and the compd. represented by the formula I. A styrene-maleic hemiester copolymer is preferably used as the film forming polymer and a compd. represented by formula II as the photopolymn. initiator. In the formulae I, II, R1 is methyl or ethyl, each of R2 and R4 is H, methyl or the like and R3 is H, Cl or the like. The adhesion of a cured image to the surface of a substrate on which the image is formed is improved, the swelling and stripping of the cured image by etching are prevented and a minute image can be formed.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] This invention relates to an image forming material comprising a photosensitive resin layer provided on a transparent support.

[Prior Art] This type of image forming material is a substrate on which an image is to be formed, such as an insulating base made of a glass plate or a plastic film, and a conductive material such as an aluminum film or an ITO film (indium oxide-tin oxide composite film). The photosensitive resin layer is heat-pressed and laminated on the surface of the conductive layer of the substrate on which the layer is formed, with the photosensitive resin layer on the inside, and after this lamination, pattern exposure is performed from the transparent support side through a predetermined original image. After peeling off only the transparent support, the unexposed portions of the photosensitive resin layer are removed with a developer and developed, thereby forming an image of the photosensitive resin cured by exposure on the substrate.

After this development, a circuit forming process is performed, such as etching away the conductive layer exposed by removing the non-exposed areas with an etching solution, or forming a plating layer on this layer using an appropriate plating solution. As a result, a circuit board is obtained in which a patterned conductive layer or a patterned plating layer is formed on an insulating base. Here, the photosensitive resin layer cured by the exposure, that is, the cured image, functions as a mask material in the circuit formation processing step, and is removed with a reagent stronger than the developer after this processing step. .

Conventionally, as an image forming material used for such purposes, a cured image formed from this material is used as a substrate (conductor layer).
From this point of view, it is desirable that the mask material has excellent adhesion with other materials, and has excellent chemical resistance, particularly against chemicals such as etching solutions and plating solutions, so that it can fully function as a mask material. Since then, various proposals have been made regarding the material structure of the photosensitive resin layer. Most of these proposals relate to the type of photosensitive resin, but there are also known proposals in which specific additives are added to any photosensitive resin to improve the adhesiveness.

For example, in Japanese Patent Application Laid-Open No. 59-152439, a triazine derivative is used as the additive, and a mercaptide complex is formed between the triazine derivative and the metal constituting the conductive layer of the substrate, thereby creating a cured image. It has been proposed to improve the adhesion to the substrate and improve the chemical resistance.

[Problem that the invention seeks to solve]

However, according to experimental studies conducted by the inventors, conventionally known image forming materials such as those proposed above do not have a conductive layer on a substrate on which an image is to be formed, and the surface roughness of the conductive layer is as large as about 2 to 5 μm. Although it satisfies adhesion with the cured image to some extent and exhibits relatively good chemical resistance, it is difficult to prevent surface roughness of conductive layers that require precise circuit formation such as in liquid crystal display devices and electrochromic display devices. For substrates with a thickness of 1 pn or less, the adhesiveness described above is insufficient, and the cured image may bulge or peel during circuit forming processes such as etching and plating, making it impossible to fully perform its function as a mask material. It turns out that it may disappear.

Therefore, the present invention aims to solve the above problems;
In other words, the object of the present invention is to provide an image forming material that provides a cured image with excellent chemical resistance and allows precise circuit formation even on a substrate whose conductive layer has a surface roughness of 1 p or less.

[Means for solving problems]

As a result of intensive studies to achieve the above object, the inventors discovered that when various photosensitive resins contain a specific compound that has never been used before, the surface roughness of the conductive layer can be improved. An image-forming material is obtained that has excellent adhesion between the cured image and the substrate and can sufficiently function as a mask material even for a substrate whose surface temperature is less than IP, thereby making it possible to form precise circuits. After discovering that this was the case, he completed this invention.

That is, this invention provides the following formula (I) on a transparent support.
); (In the formula, %R1 is a methyl group or an ethyl group, R2 is hydrogen,
The invention relates to an image forming material provided with a photosensitive resin layer containing a compound represented by a methyl group or an ethyl group.

[Structure and operation of the invention] The compound represented by the formula (I) used in this invention is a type of triphenylmethane dye that develops color by reacting with coexisting radicals, and its reactivity with the radicals is phenyl. Because it is very large due to the specific substituent introduced into the group, it easily reacts with radicals generated when the photosensitive resin layer is cured by exposure to produce an intermediate. In this invention, by using such a compound, the adhesion between the cured image and the conductive layer of the substrate is greatly improved, and it is presumed that the reason for this is probably based on the formation of the above-mentioned intermediate. be done.

However, the details are not necessarily clear.

Specific examples of such compounds include 4, 4', 4",
N-diethylbenzenamine), 4,4,4''-methylidine-tris (N-N-dimethyl-3-methylbenzenamine), 4,4',4''-methylidine-tris (
N-N-diethyl-3-methylbenzenamine), 4.
Examples include 4',4''-methylidine-tris (N-N-dimethyl-3-ethylbenzenamine), 4,4',i'-methylidine-tris (N-N-diethyl-3-ethylbenzenamine), and the like.

In the present invention, the type of photosensitive resin layer that should contain the above-mentioned compound is not limited, and conventionally known ones can be widely applied. Among these, the most common type is one that polymerizes and hardens upon exposure to light, and a typical example is one that contains a film-forming polymeric substance, an ethylenically unsaturated polymerizable compound, and a photopolymerization initiator as essential components. It is included.

Hereinafter, this polymerization-curing type will be taken as an example, and its material structure will be explained in more detail.

When using an alkaline aqueous solution as a developer for removing the photosensitive resin layer in non-exposed areas and forming a desired cured image, the above-mentioned film-forming polymeric substances include styrene-maleic acid half ester, etc. The polymer can be used alone or together with other polymers such as partial hydrolysates of polymethyl methacrylate, copolyamides, polyvinyl alcohol, polychloroprene, styrene-butadiene copolymer combs, etc. It is desirable to use them together in a proportion of 50% by weight or less.

The maleic acid half ester constituting the above styrene-maleic acid half ester copolymer is produced by reacting maleic anhydride with an alcohol having usually 3 to 6 carbon atoms such as inpropyl alcohol or butyl cellosolve. It is a half ester in which one free carboxyl group remains.

The copolymerization ratio of this half ester and styrene is preferably such that the half ester accounts for about 40 to 80% by weight in the copolymer.

The weight average molecular weight of such a styrene-maleic acid half ester copolymer is preferably in the range of 50,000 to 130,000. If the molecular weight becomes too low, not only will film forming properties deteriorate, but the exposed and hardened portions will be less resistant to developing solutions (alkaline aqueous solutions) and etching solutions, so developing properties and chemical resistance will tend to decline.

Furthermore, if the molecular weight becomes too high, the removability of the non-exposed portions with a developer will be poor, resulting in poor developability.

On the other hand, it is also possible to form a cured image using a developer other than an alkaline aqueous solution, and in this case, an appropriate film-forming polymeric substance can be used accordingly.

Typical examples of such polymeric substances include chlorinated polyolefins such as chlorinated polyethylene and chlorinated polypropylene, polymethyl methacrylate, polymethyl acrylate, polyvinyl chloride, polyvinylidene chloride, polyvinyl butyral, polyvinyl acetate, and chlorinated polyolefins such as chlorinated polyethylene and chlorinated polypropylene. Examples include H=-vinyl acetate copolymer, polyisoprene, chlorinated rubber, polychloroprene, polychlorosulfonated ethylene, vinylidene chloride-acrylonitrile copolymer, polychlorosulfonated propylene, and saturated polyester.

Ethylenically unsaturated polymerizable compounds to be used in combination with such film-forming polymeric substances include compounds having one ethylenically unsaturated bond and compounds having two or more.What is used as a developer? An appropriate one is used in consideration of the combination with the film-forming polymeric substance.

Examples of compounds having one ethylenically unsaturated bond include acrylic acid or acrylic esters, methacrylic acid or methacrylic esters, acrylamides, methacrylamides, allyl compounds, vinyl ethers, vinyl esters, N- These include vinyl compounds, styrenes, and crotonic acid esters.

Specific examples of acrylic esters include alkyl acrylates such as propyl acrylate, butyl acrylate, amyl acrylate, ethylhexyl acrylate, and octyl acrylate, and specific examples of methacrylic esters include is methyl methacrylate,
Examples include alkyl methacrylates such as ethyl methacrylate, propyl methacrylate, and isopropyl methacrylate.

In addition to acrylamide, N
-methylacrylamide, N-ethylacrylamide,
Examples include N-alkylacrylamides such as N-butylacrylamide, N-isopropylacrylamide, Nt-butylacrylamide, and N-ethylhexylacrylamide.

In addition to methacrylamide, methacrylamides include N-methylmethacrylamide, N-ethylmethacrylamide, N-isopropylmethacrylamide, N-t-
Examples include N-alkyl methacrylamide such as butyl methacrylamide and N-ethylhexyl methacrylamide.

Allyl compounds include allyl esters such as allyl acetate, allyl caproate, allyl caprylate, allyl laurate, and allyl palmitate. Vinyl ethers include hexyl vinyl ether, octyl vinyl ether, decyl vinyl ether, and ethylhexyl vinyl ether. Examples include alkyl vinyl ethers.

In addition, vinyl esters include vinyl butyrate,
vinyl isobutyrate, vinyl trimethyl acetate,
Vinyl diethyl acetate, vinyl valerate, vinyl caproate, etc. are listed, and the styrenes include, in addition to styrene, methylstyrene, chloromethylated styrene, alkoxystyrene, halogenated styrene, and styrene benzoate. Furthermore, examples of crotonate esters include methyl crotonate, ethyl crotonate, butyl crotonate, hexyl crotonate, isopropyl crotonate, and the like.

A compound having two or more ethylenically unsaturated bonds is more preferably used than a compound having one ethylenically unsaturated bond. Those belonging to this category include esters of polyhydric alcohols and acrylic acid or methacrylic acid, and di(meth)acrylates or higher poly(meth)acrylates are used. The polyhydric alcohols include polyethylene glycol, polybutylene oxide to polyethylene glycol, (β-hydroxyethoxy)benzene, glycerin, diglycerin, neopentyl glycol, trimethylolpropane, trimethylolpropane, pentaerythritol, dipentaerythritol, Sorbitan, sorbitol, 1,4-butanediol, 1,2,4-butanetriol, 2-butenoto-4-diol, 2-butyl-2-ethyl-propanediol, 2-butenoto-4-diol, 1,3-
Examples include propanediol, triethanolamine, decalindiol, and 3-chloroto-2-propanediol.

Polyethylenically unsaturated polymerizable compounds other than those listed above,
Polyester acrylates or polyester methacrylates synthesized from acrylic acid or methacrylic acid, polyhydric alcohols, and polybasic acids, or esters of acrylic acid or methacrylic acid after addition reaction of ethylene oxide or propylene oxide to bisphenol. Di(meth) obtained by reaction
Acrylates can also be used.

The various ethylenically unsaturated polymerizable compounds mentioned above are usually used in an amount of 10 to 300 parts by weight, preferably 50 to 200 parts by weight, per 100 parts by weight of the film-forming polymeric substance. good.

If the amount used is too small or too large, it becomes difficult to form a photosensitive resin layer with excellent developability and chemical resistance, which is not preferable.

Next, examples of photopolymerization initiators include carbonyl compounds, organic sulfur compounds, peroxides, redox compounds, azo and diazo compounds, halogen compounds, and thioxanthone compounds. Among these, particularly suitable ones are:
It is a thioxanthone compound represented by the following formula (II); convex (wherein R3 is hydrogen, methyl group, ethyl group, isopropyl group, or chlorine, and R4 is hydrogen, methyl group, or ethyl group).

Among the above thioxanthone compounds, the most preferred examples include thioxanthone in which R3 and R4 in the above formula (II) are both hydrogen, 2,4-dimethylthioxanthone in which both are methyl groups, and 2,4-dimethylthioxanthone in which both are ethyl groups. Examples thereof include 4-diethylthioxanthone, 2-chlorothioxanthone in which R3 is chlorine and R4 is hydrogen, and 2-isopropylthioxanthone in which R3 is an inpropyl group and R4 is hydrogen. The radicals generated by these thioxanthone compounds easily react with the compound represented by the formula (I) above, and the intermediate produced by this reaction greatly improves the adhesive strength between the cured image and the conductive layer of the substrate. It has the function of significantly increasing chemical resistance. In addition, P-dimethylaminobenzoic acid isoamyl ester, P-dimethylaminobenzoic acid ethyl ester, etc. may be used together with such a thioxanthone compound.

Specific examples of the carbonyl compounds that can be used as photopolymerization initiators other than thioxanthone compounds include: C, benzoin, benzoin methyl ether, benzoin isopropyl ether, benzoin butyl ether, benzyl dimethyl ketal, benzophenone, and anthraquinone. , 2-methylanthraquinone, 2-t-butylanthraquinone, 9.1
〇-Phenanthrenequinone, diacetyl, benzyl, etc. Examples of organic sulfur compounds include dibutyl disulfide, dioctyl disulfide, dibenzyl disulfide, diphenyl disulfide, dibenzoyl disulfide, and diacetyl disulfide.

Examples of peroxides include hydrogen peroxide, di-t-butyl peroxide, benzoyl peroxide, and methyl ethyl ketone peroxide. Furthermore, the redox compound consists of a combination of a peroxide and a reducing agent,
These include ferrous ions and hydrogen peroxide, ferrous ions and persulfate ions, and ferric ions and peroxide.

Examples of azo and diazo compounds include .alpha..alpha.'-azobisisobutyronitrile, 2-azobis-2-methylbutyronitrile, 1-azobis-cyclohexanecarbonitrile, and diazonium salts of p-aminodiphenylamine. Halogen compounds include chloromethylnaphthyl chloride, phenacyl chloride, chloroacetone, β
-Naphthalenesulfonyl chloride, xylenesulfonyl chloride, etc. can be mentioned.

These photopolymerization initiators may be used alone or in combination of two or more. The amount used is usually 0.5 to 100 parts by weight of the ethylenically unsaturated polymerizable compound.
The amount may be 20 parts by weight, preferably in the range of 5 to 10 parts by weight. If the amount is too small, the exposure curability of the photosensitive resin layer will be poor, and if it is used in excess of a predetermined amount, no further improvement in curability will be observed, which is economically disadvantageous.

A photosensitive resin layer of the type that polymerizes and hardens upon exposure to light has the above-mentioned film-forming polymeric substance, ethylenically unsaturated polymerizable compound, and photopolymerization initiator as essential components, and the above-mentioned formula (
It consists of a photopolymerizable composition containing the compound represented by formula (I), and the content of the compound represented by formula (I) in this composition is 100% of the above photopolymerization initiator.
10 to 500 parts by weight, preferably 50 to 3 parts by weight
00 parts by weight, and the proportion in the entire composition is usually about 0.1 to 10% by weight.

Note that the above photopolymerizable composition may contain a thermal polymerization inhibitor and a coloring agent as necessary, and if desired, various additives such as a plasticizer and an adhesion promoter may be blended. is also possible.

Thermal polymerization inhibitors include paramethoxyphenol, hydroquinone, alkyl- or aryl-substituted hydroquinone, t-butylcatechol, pyrogallol, cuprous chloride, phenothiazine, floranil, naphthylamine, β
- Naphthol, 2,6-di-t-butyl-p-cresol, pyridine, nitrobenzene, dinitrobenzene, p
- Examples include organic copper acids such as toluidine, methylene blue, and copper acetate. These thermal polymerization inhibitors are usually used in an amount of 0.001 to 5 parts by weight per 100 parts by weight of the ethylenically unsaturated polymerizable compound.
Used in parts by weight.

Examples of colorants include carbon black, iron oxide,
Pigments such as phthalocyanine pigments and azo pigments, methylene blue, crystal violet, and rhodamine B1
There are dyes such as axin, auramine, azo dyes, and anthraquinone dyes, but those that do not absorb light at the absorption wavelength of the photopolymerization initiator are preferred. The amount of the colorant added is usually in the range of 0.01 to 5 parts by weight based on 100 parts by weight of the total amount of the film-forming polymeric substance and the ethylenically unsaturated polymerizable compound.

In the present invention, such a photopolymerizable composition is uniformly dissolved in a normal solvent, cast on a transparent support, and then dried to obtain a polymerization ratio of 5 to 100%.
F, particularly preferably a photosensitive resin layer having a thickness of about 10 to 50 P is formed to prepare an image forming material.

The above-mentioned solvent is not particularly limited as long as it can dissolve the photopolymerizable composition, and may be one type or a mixed solvent of two or more types. Specific examples include acetone, methyl ethyl ketone, methyl isobutyl ketone, methyl cellosolve, ethyl cellosolve, ethyl acetate, butyl acetate, dichloromethane, chloroform, methanol, ethanol, and the like.

On the other hand, the above-mentioned transparent support is desired to have excellent surface smoothness so that a photosensitive resin layer of uniform thickness can be formed thereon, and it is also desirable that the above-mentioned transparent support have excellent surface smoothness in order to form a uniformly thick photosensitive resin layer thereon. It is desirable that the material is selected so that it can be easily peeled off, and that the material is not surface-treated. Furthermore, it must have excellent light transparency so that the photosensitive resin layer can be well photopolymerized by exposure to light.
For example, it is required that the light transmittance is 30% or more, particularly preferably 65% or more in the wavelength range of 290 to 500 nm.

There are various kinds of transparent supports that satisfy these required characteristics, but a typical example is a polyethylene terephthalate film with a thickness of 5 to IQQ, especially about 10 to 30 m. , polyethylene film, polypropylene film, etc. Among these, polyethylene terephthalate film is the most preferred.

The image-forming material of the present invention can be stored by winding it into a roll or stacking it in layers. In this case, in order to prevent the materials from adhering to each other, a transparent support formed with a photosensitive resin layer is used. Either apply mold release treatment to the back surface of the photosensitive resin layer using a mold release agent such as silicone resin, or attach a protective film with a mold release effect, such as polyethylene film, polypropylene film, or polytetrafluoroethylene film, to the photosensitive resin layer. It is better to leave it there. The above-mentioned protective film is also useful for preventing deterioration of the photosensitive resin layer over time.

An image of a predetermined pattern can be formed using the image forming material of the present invention in accordance with a conventionally known method.

That is, first, an image is formed on the surface of the conductive layer of a substrate on which an image is to be formed, for example, a conductive layer such as an ITO film or an aluminum film is formed on an insulating base made of a glass plate or a plastic film. If the materials have a protective film, this is peeled off, and then the materials are laminated by heat and pressure bonding, usually at a temperature of 90 to 130°C, so that the photosensitive resin layer side faces inside.

Next, the laminate is exposed to actinic light in a pattern through the original image from the side of the transparent support. As active rays, 200
-700 nm, preferably 250-500 nm, and suitable light sources include low-pressure, high-pressure, and ultra-high pressure mercury lamps, xenon lamps, carbon arc lamps, halogen lamps, germicidal lamps, etc. be.

After the above-mentioned exposed transparent support is peeled and removed, only the non-exposed areas are selectively removed using a known method such as spray method, rocking dipping method, brushing method, or scraping method using an appropriate developer. Develop by removing. As a result, the photosensitive resin layer cured by exposure is formed on the substrate as a clear image.

As the above developer, an alkaline aqueous solution or a solution mainly containing an organic solvent is used depending on the material composition of the photosensitive resin layer. Among these, an alkaline aqueous solution is particularly preferred, and the alkaline aqueous solution when the film-forming polymeric substance is the above-mentioned styrene-maleic acid half ester copolymer will be described in more detail below.

Alkali components include alkali hydroxides consisting of hydroxides of lithium, sodium or potassium, lithium,
Alkali carbonates such as sodium or potassium carbonates and bicarbonates, alkali metal phosphates such as potassium phosphate and sodium phosphate, and alkali metal pyrophosphates such as sodium pyrophosphate and potassium pyrophosphate are used. Among these, sodium carbonate is particularly preferred.

The concentration of the alkali component in the aqueous solution is approximately 0.5 to 3% by weight, and if it is higher than this, there is a risk that even the first exposed portion may be partially removed, resulting in poor developability. The temperature during development is appropriately adjusted depending on the type of each component of the photosensitive resin layer, but is generally about 20 to 30°C. In addition, the above-mentioned developer may contain a surfactant, an antifoaming agent, and a small amount of an organic solvent for accelerating development, if necessary.

After forming the image in this manner, a circuit forming process is performed in which the exposed conductor layer is etched away using an etching solution using the cured image as a mask material.

In this process, for example, a mixed aqueous solution of hydrochloric acid and nitric acid having a volume ratio of hydrochloric acid:water:nitric acid of 1:1:0.08 is used as an etching solution, and the substrate on which the image has been formed is placed in this solution for 30 minutes.
This can be done by a method of rocking immersion for 0 to 120 seconds.

Alternatively, the same process as above may be performed using a mixed aqueous solution having a volume ratio of phosphoric acid: nitric acid: acetic acid: water of about 20:10.5 as an etching solution. Note that instead of the above etching process, a plating layer may be formed on the exposed conductive layer using a known plating solution.

In these various circuit forming processing steps, the cured image exhibits sufficient resistance to chemicals such as etching solutions and plating solutions, and fully functions as a mask material. In particular, this function is independent of the surface roughness of the conductor layer on the substrate on which the image is to be formed, i.e., this surface roughness is typically 0.1 μm or less. (Even if it is up to 11μ, it is exhibited.

After this circuit forming process, the cured image is processed using a reagent stronger than the developer, for example, when the developer is the above-mentioned alkaline aqueous solution, an alkaline aqueous solution that is stronger than this (for example, about 2 to 7% by weight of hydroxide) is used. By removing the patterned conductor layer or patterned plating layer on the insulating base, a circuit board can be obtained in which a patterned conductor layer or a patterned plating layer is precisely formed on the insulating base.

〔Effect of the invention〕

As described above, in the present invention, the specific compound represented by the formula CI) is included in the photosensitive resin layer provided on the transparent support. Even when the surface roughness of the layer is 1μ or less, the adhesion between the layer and the cured image is improved, and the cured image does not develop such as blistering or peeling during circuit forming processing steps such as etching. A forming material can be obtained. Therefore, this image forming material can be advantageously applied to applications that require precise circuit formation, such as liquid crystal display devices and electrochromic display devices.

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

Example 1 2,4-diethylthioxanthone 8 parts p
-Dimethylaminobenzoic acid isoamyl ester 3
Victoria Pure Blue 0.08
0.04 parts Hydroquinone The above composition was uniformly dissolved and mixed in ethyl acetate to prepare a photopolymerizable composition solution having a solid content concentration of 40% by weight. This solution was applied with an applicator onto a 25μ thick transparent polyethylene terephthalate film as a transparent support, and heated and dried at 80°C for 5 minutes to give an approx.
A photosensitive resin layer having a thickness of 1 was formed to obtain an image forming material of the present invention.

Next, this image forming material was applied as a conductive layer on a transparent polyethylene terephthalate film having a thickness of 125 pn as an insulating base.
A substrate made of a 500 Ω/C♂ type transparent conductive film formed with a tin oxide composite film was heat-pressed onto the surface of the conductive layer at 90'C with the photosensitive resin layer facing inside. and laminated.

A negative original is brought into close contact with the surface of the transparent support of this laminate,
This original was exposed to light for 20 seconds at a distance of 60 cm from the light source using a 3 KW ultra-high pressure mercury lamp.

Thereafter, the transparent support was peeled off, and developed by immersion in a 1% by weight sodium carbonate (N a 2 C03) aqueous solution with shaking for 3 minutes at 25°C, resulting in a line width of 75 μm.
Clear images with a resolution of up to

The substrate with this cured image is then treated with phosphoric acid: nitric acid:
It was immersed for 30 seconds in an etching solution consisting of a mixed aqueous solution with a volume ratio of acetic acid:water of 20:1:0.5, and the exposed conductor layer was etched away using the cured image as a mask material.

After that, it was washed with water for 10 minutes, and then heated and dried in a hot air dryer at 100°C. During this etching and water washing process, the cured image did not peel off and showed very good resistance.

Finally, the cured image is removed by treatment with a 3% by weight aqueous sodium hydroxide solution, and further washed with water and dried.
A circuit board was obtained having a patterned conductor layer on an insulating base. The removability of the cured image at this time was good and could be easily and completely removed using the aqueous solution.

Comparative Example 1 4, 4', 4 in the composition for forming a photosensitive resin layer
An image-forming material was obtained in the same manner as in Example 1, except that 2 parts of "-methylidine-tris (N-N-diethyl-3-methylbenzenamine) was not blended, and this was used in the same manner as in Example 1. As a result, development was almost the same as in Example 1, but the cured image peeled off when washed with water after etching.

Example 2 2.4- in the composition for forming a photosensitive resin layer
2,2-dimethoxy-2 instead of 8 parts of diethylthioxanthone and 2 parts of 4,4,4"-methylidine-tris(N-N-diethyl-3-methylbenzenamine)
The image forming material was prepared in the same manner as in Example 1, except that 4 parts of -phenylacetophenone (photopolymerization initiator) and 5 parts of 4,4',4''-methylidine-tris (N-N-dimethylbenzenamine) were used. Using this, development and circuit formation were attempted in the same manner as in Example 1.As a result, a clear image with a resolution of up to 125P line width could be formed in the development stage, and etching for circuit formation was possible. During processing and subsequent water washing, the cured image showed good resistance without peeling, and finally a circuit board with a sharply patterned conductive layer on an insulating base could be obtained.

Comparative Example 2 4.4.4'' in the composition for forming the photosensitive resin layer
An image forming material was obtained in the same manner as in Example 2, except that 5 parts of -methylidine-tris (N-N-dimethylbenzenamine) was not blended, and using this image-forming material was developed and processed in the same manner as in Example 1. I tried to form it. As a result, the development was almost the same as in Example 2, but the cured image peeled off during the etching process for circuit formation.

Example 3 2-inpropylthioxanthone 10 parts Victoria Pure Blue ○, OS part Hydroquinone 0.04 parts Example 1 except that the above composition was used as the composition for forming the photosensitive resin layer. An image forming material was obtained in the same manner, and using this material, development and circuit formation were attempted in the same manner as in Example 1.

As a result, it is possible to form a clear image with a resolution of up to 100 μm in line width in the development stage, and the cured image shows good resistance without peeling during the etching process for circuit formation and the subsequent water washing process, and the final It was possible to obtain a circuit board with a sharply patterned conductive layer on an insulating base.

Comparative Example 3 4, 4', 4 in the composition for forming a photosensitive resin layer
An image forming material was obtained in the same manner as in Example 3, except that 5 parts of "-methylidine-tris(N-N-dimethyl-3-ethylbenzenamine) was not blended, and the same procedure as in Example 1 was carried out using this material. As a result, the development was almost the same as in Example 3, but the cured image leaked out and peeled off during the etching process for forming the circuit.

Claims (3)

[Claims] (1) On a transparent support, the following formula (I); ▲There are mathematical formulas, chemical formulas, tables, etc.▼...(I) (In the formula, R_1 is a methyl group or ethyl group, R_2 is hydrogen or a methyl group. or an ethyl group). (2) The photosensitive resin layer contains the compound represented by formula (I), a film-forming polymeric substance, an ethylenically unsaturated polymerizable compound, and a photopolymerization initiator as essential components, and is capable of initiating photopolymerization. The agent is the following formula (II); ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼... (III) (In the formula, R_3 is hydrogen, methyl group, ethyl group, isopropyl group, or chlorine, R_4 is hydrogen, methyl group or an ethyl group) The image forming material according to claim (1). (3) The image forming material according to claim (2), wherein the film-forming polymeric substance comprises a styrene-maleic acid half ester copolymer.