JPH08239438A - Photopolymer and alkali-developable photopolymer composition containing same - Google Patents

Abstract

PURPOSE: To obtain a photopolymer useful to obtain a photopolymer composition being developable with an aqueous alkali solution, showing excellent properties as a solder mask material and giving a tack-free coating film after precuring. CONSTITUTION: This photopolymer is represented by the formula [wherein R<1> and R<2> are each hydrogen, lower alkyl or halogen; R<3> is hydrogen or methyl; X is null or -CO-, -SO2 -, -C(CF3 )2 -, -Si-(CH3 )2 -, -C(CH3 )2 - or -O-; Y is a residue of an unsaturated isocyanate; Z is a residue of an intramolecular anhydride of an (un)saturated polybasic acid; and (n) which is the average degree of polymerization is 0.5-5].

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a novel photosensitive resin, an intermediate thereof, and a photosensitive resin composition containing the photosensitive resin, which is excellent in heat resistance and can be developed with an alkali.

[0002]

2. Description of the Related Art A solder mask pattern, a resist pattern for chemical plating, etc. are required when manufacturing a printed wiring board. Generally, a method of patterning a photosensitive resin composition by screen printing is widely adopted. Has been done.

By the way, with recent higher integration and higher functionality of semiconductor chips, further miniaturization, higher performance and higher functionality of electronic devices using semiconductor chips are required. It has become. For this reason, high density wiring and surface mounting of mounted components are required for printed wiring boards used in electronic devices, and accordingly, solder masks formed on the boards at the time of manufacturing the printed wiring boards. Also for the pattern, a thick film and high dimensional accuracy are required.

However, there is a problem that such a requirement cannot be satisfied by a method of patterning a photosensitive resin composition by screen printing.

Therefore, patterning has been carried out by a photographic method corresponding to such a high-density printed wiring board, and various photo solder resist materials for that purpose have been proposed. For example, as a photo solder resist material, use of a photosensitive composition mainly composed of a photosensitive epoxy resin having a chalcone group in the main chain and an epoxy resin curing agent (Japanese Patent Laid-Open No. 58-62636), A photosensitive composition containing a novolac type epoxy acrylate having an epoxy group and a photopolymerization initiator as main components (JP-A-61-272) has been proposed.

However, these photosensitive compositions are
Since an organic solvent is used as the developing solution, there is a problem in that environmental pollution and deterioration of working environment occur.

Therefore, in order to enable development with an alkaline aqueous solution instead of an organic solvent, a photosensitive composition having a free carboxyl group introduced into the molecule has been proposed. For example, a liquid solder resist ink composition containing an oligomer obtained by reacting an acid anhydride with a reaction product of a novolac type epoxy resin and acrylic acid, a photoinitiator, an epoxy resin, and a diluent is proposed. I have (Tokuhei 1-
54390). Further, an alkali-developable photosensitive material containing a photopolymerizable unsaturated compound obtained by reacting an acid anhydride with a reaction product of a bisphenol A type epoxy resin and acrylic acid, an epoxy resin, and a photoinitiator. A resin composition has been proposed (Japanese Patent Laid-Open No. 1-296240).

[0008]

However, the composition described in Japanese Patent Publication No. 1-54390 does not have sufficient resistance to acidic conditions or alkaline conditions at high temperatures, and therefore, the adhesion to the substrate after development processing is not sufficient. There was a problem that it deteriorated. Also, Japanese Patent Laid-Open No. 1-2962
In the case of the composition described in JP-A No. 40, the coating film formed after pre-cure has tackiness because it is a liquid resist. Therefore, there is a problem that when the contact exposure operation that is advantageous for improving the resolution and tapering is performed on the coating film, the mask is contaminated.

The present invention is intended to solve the above-mentioned problems of the prior art. The coating film after precure is tack-free, contact exposure is possible, and alkali development is possible, and moreover, it is light-sensitive. A photosensitive resin composition in which the coating film after irradiation and post-baking exhibits excellent properties (resolution, heat resistance, electrical properties, mechanical properties, etc.) as a solder mask material and has excellent adhesion to the substrate. The purpose is to provide.

[0010]

Means for Solving the Problems The present inventor has first introduced an unsaturated isocyanate compound into a bisphenol epoxy resin by reacting an unsaturated isocyanate compound with a hydroxyl group of the bisphenol epoxy resin, and further A novel bisphenol type epoxy acrylate resin is obtained by reacting epoxy groups at both ends with (meth) acrylic acid to form a (meth) acrylic acid ester group and a hydroxyl group. By forming a photosensitive resin composition mainly composed of a photosensitive resin obtained by introducing a polybasic acid intramolecular anhydride residue into the formed hydroxyl group to introduce a polybasic acid intramolecular anhydride residue The inventors have found that the above object can be achieved and completed the present invention.

That is, the present invention is based on the formula (1)

[0012]

Embedded image (In the formula, R ¹ and R ² are each independently hydrogen, a lower alkyl group or halogen, R ³ is hydrogen or a methyl group, X is absent or —CO—, —SO ₂ —, —
_{C (CF 3) 2 -,} - Si (CH 3) 2 -, - C (CH 3) 2 - or a -O-, Y is an unsaturated isocyanate residue, Z is a multi saturated or unsaturated It is an anhydride residue in the basic acid molecule, and the average degree of polymerization n is a number of 0.5 to 5. The photosensitive resin represented by these is provided.

The present invention also provides the following component (A),
(B) and (C) (A) Photosensitive resin of the above formula (1) 100 parts by weight (B) Compound having at least one epoxy group in the molecule 5 to 50 parts by weight (C) Photopolymerization initiator Provided is a photosensitive resin composition containing 0.1 to 30 parts by weight.

Further, the present invention provides the formula (A) which is a precursor of the photosensitive resin of the formula (1).

[0015]

[Chemical 4] (Wherein R ¹ , R ² , R ³ , X, Y, Z and n are represented by the formula (1)
As defined in. ) A bisphenol type epoxy acrylate resin represented by

The present invention will be described in detail below.

In the photosensitive resin of the formula (1) of the present invention,
In the definition of R ¹ and R ² , examples of the lower alkyl group include a methyl group, an ethyl group, a propyl group and an isopropyl group, and among them, a methyl group is preferable. Also, R
Preferable examples of the halogen of ¹ and R ² include chloro and bromo.

In the photosensitive resin of the formula (1), specific examples of the bisphenol component surrounded by the brackets [] include bis (4-hydroxyphenyl) ketone and bis (4) when X is --CO--. Examples include -hydroxy-3,5-dimethylphenyl) ketone and bis (4-hydroxy-3,5-dichlorophenyl) ketone. Also, X is −
In the case of SO ₂ −, bis (4-hydroxyphenyl)
Examples thereof include sulfone, bis (4-hydroxy-3,5-dimethylphenyl) sulfone, and bis (4-hydroxy-3,5-dichlorophenyl) sulfone. X is -C (C
F _{3) 2} - in the case of bis (4-hydroxyphenyl)
Hexafluoropropane, bis (4-hydroxy-3,
Examples thereof include 5-dimethylphenyl) hexafluoropropane and bis (4-hydroxy-3,5-dichlorophenyl) hexafluoropropane. X is -Si (CH _{3) 2}
In the case of −, bis (4-hydroxyphenyl) dimethylsilane, bis (4-hydroxy-3,5-dimethylphenyl) dimethylsilane, bis (4-hydroxy-3,5)
5-dichlorophenyl) dimethylsilane etc. are mentioned. When X is —CH ₂ —, bis (4-hydroxyphenyl) methane, bis (4-hydroxy-3,5-dichlorophenyl) methane, bis (4-hydroxy-3,
5-dibromophenyl) methane and the like can be mentioned. X is-
C (CH _{3) 2} - in the case of 2,2-bis (4-hydroxyphenyl) propane, 2,2-bis (4-hydroxy-3,5-dimethylphenyl) propane, 2,2-bis ( 4-hydroxy-3,5-dichlorophenyl) propane, 2,2-bis (hydroxy-3-methylphenyl)
Examples include propane and 2,2-bis (4-hydroxy-3-chlorophenyl) propane. When X is -O-, bis (4-hydroxyphenyl) ether, bis (4-hydroxy-3,5-dimethylphenyl) ether, bis (4-hydroxy-3,5-dichlorophenyl) ether and the like can be mentioned. To be When X is absent, 4,4'-biphenol, 3,3'-biphenol and the like can be mentioned. Further, these may be a mixture of any of them. In particular, a preferable combination of R ¹ , R ² and X can include a case where R ¹ and R ² are hydrogen and X is —C (CH ₃ ) ₂ —.

In the photosensitive resin of the formula (1), Y
As the unsaturated isocyanate residue, a hydrocarbon group having a (meth) acroyloxyalkoxycarbonylamino group is preferable. In this case, the (meth) acroyloxyalkoxycarbonylamino group is particularly preferably an acroyloxyethoxycarbonylamino group or a metacroyloxyethoxycarbonylamino group. As the hydrocarbon group, an alkyl group such as a hexyl group, a phenyl group, a toluyl group, a xylyl group, an naphthyl group, an aryl group such as a phenylmethylphenyl group, a hydrogenated xylyl group, an alicyclic group such as isophorone-yl group, etc. An alkyl group and the like can be preferably mentioned. As a specific unsaturated isocyanate residue, an acroyloxyethoxycarbonylamino- or methacroyloxyethoxycarbonylamino-toluyl group can be particularly preferably cited.

Such unsaturated isocyanate residues are
It can be derived from a compound having at least one isocyanate group and an unsaturated group in the molecule. Such unsaturated isocyanate compound is preferably 1 mol or more of unsaturated monoalcohol, more preferably 1.2 to 1.5 mol of unsaturated monoalcohol per 1 mol of diisocyanate. Compounds obtained by reacting can be mentioned. Here, as the diisocyanate for forming the unsaturated isocyanate compound, for example, 2,4-tolylene diisocyanate, a mixture of 2,4-tolylene diisocyanate and 2,6-tolylene diisocyanate, Paraphenylene diisocyanate, diphenylmethane diisocyanate,
1,5-naphthylene diisocyanate, xylylene diisocyanate, hydrogenated xylylene diisocyanate, hexamethylene diisocyanate, isophorone diisocyanate and the like can be mentioned. Further, as the unsaturated monoalcohol, for example, a compound having an unsaturated group such as a (meth) acryloyl group and a hydroxyl group in one molecule can be preferably mentioned, and specifically, acrylic acid, methacrylic acid, etc. Compounds obtained by reacting the above unsaturated carboxylic acid with an alkylene monoepoxide such as ethylene oxide or propylene oxide can be mentioned.

In the photosensitive resin of the formula (1), the saturated or unsaturated polybasic acid intramolecular anhydride residue of Z is preferably a hydrocarbon group having a carboxyl group. Here, examples of the hydrocarbon group include an alkyl group such as a butyl group, an alkenyl group such as a butenyl group, an aryl group such as a phenyl group, and an alicyclic alkyl group such as a cyclohexyl group. As a specific saturated or unsaturated polybasic acid anhydride residue, a carbonyltetrahydrophenyl group, a carboxycyclohexyl group, a carboxyphenyl group and the like can be particularly preferably mentioned. Examples of the acid anhydride for forming such a saturated or unsaturated polybasic acid anhydride residue include, for example, maleic anhydride, succinic anhydride, itaconic anhydride, phthalic anhydride, tetrahydrophthalic anhydride, and hexahydrate. Dibasic acid anhydrides such as hydrophthalic acid, methylhexahydrophthalic anhydride, endomethylenetetrahydrophthalic anhydride, methylendomethylenetetrahydrophthalic anhydride, chlorendic anhydride, methyltetrahydrophthalic anhydride; trimellitic anhydride, anhydrous Aromatic polyvalent carboxylic acid anhydrides such as pyromellitic acid and benzophenone tetracarboxylic acid dianhydride; and similar 5- (2,5-dioxotetrahydrofuryl)
Examples thereof include polyvalent carboxylic acid anhydride derivatives such as -3-methyl-3-cyclohexene-1,2-dicarboxylic acid anhydride.

In the photosensitive resin of the formula (1) of the present invention, n means the average degree of polymerization of the bisphenol type unit mainly constituting the main chain of the photosensitive resin. If the numerical range is too small, tackiness occurs because it is in a semi-solid state at room temperature, and the contact exposure operation becomes difficult, and if it is too large, the photosensitivity is remarkably reduced.

The acid value of the photosensitive resin of the formula (1) of the present invention is preferably 30 to 150 mgKOH, because if the acid value is too small, the alkali developability decreases, and if it is too large, the development becomes impossible. It is preferable to use an acid value of / g.

Next, the method for producing the photosensitive resin of the formula (1) of the present invention will be described, wherein R ¹ and R ² are hydrogen and X is —C (CH ₃ ) ₂
And the case where Y is an acroyloxyethoxycarbonylamino- or a metacroyloxyethoxycarbonylamino-toluyl group will be described as an example according to the following reaction scheme.

[0025]

Embedded image

[0026]

[Chemical 6] First, the hydroxyl group of the bisphenol A type epoxy resin of the formula (2) is obtained by the reaction of tolylene diisocyanate and hydroxyethyl (meth) acrylic acid, and the formula (3) is obtained.
To react with the unsaturated isocyanate compound (R ⁴ = hydrogen or methyl group) to form a compound of formula (4). In this case, it is preferable to react 0.5 equivalent or more of the unsaturated isocyanate compound of the formula (3) per 1 equivalent of the hydroxyl group of the bisphenol A type epoxy resin.

Next, an epoxy group at both ends of the compound of formula (4) is reacted with an unsaturated carboxylic acid of formula (5) to synthesize a novel bisphenol A type epoxy acrylate resin of formula (6). To do.

Next, the hydroxyl group of the resin of the formula (6) is heated with an intramolecular acid anhydride in a solvent (for example, a ketone solvent, a cellosolve solvent, etc.) to react with the compound of the formula (1).
A photosensitive resin of formula (7) included in is obtained. In this case, the reaction temperature is 110 to 120 ° C. in order to quantitatively react the acid anhydride and the epoxy acrylate resin.
It is preferable that

It is to be noted that, when R ¹ , R ² and X are other than those described in the reaction scheme, the same production can be carried out. In this case, the formula (A) corresponding to the bisphenol A type epoxy acrylate resin of the formula (6) is used.

[0030]

[Chemical 7] (Wherein R ¹ , R ² , X, Y and n are as defined in the formula (1)), and a novel bisphenol A type epoxy acrylate resin is obtained. This resin is a resin useful as a precursor of the photosensitive resin of formula (1).
Therefore, the resin of formula (A) is also part of the present invention.

Next, the photosensitive resin composition of the present invention containing the photosensitive resin of the formula (1) will be described.

This photosensitive resin composition of the present invention comprises the following components (A), (B) and (C) (A) photosensitive resin of the formula (1) (B) at least one epoxy in the molecule. Compound having group (C) Contains a photopolymerization initiator.

Since the photosensitive resin composition of the present invention has a free carboxyl group in the molecule, an alkaline aqueous solution can be used as a developing solution after exposure.
Examples of such an alkaline aqueous solution developer include, for example, an aqueous solution of an alkali metal or alkaline earth metal carbonate,
Examples thereof include an aqueous solution of an alkali metal hydroxide, but a weakly alkaline aqueous solution containing 1 to 3% by weight of a carbonate such as sodium carbonate, potassium carbonate or lithium carbonate can be used. Even if such a weak alkaline aqueous solution developer is used, a fine image can be precisely developed. In this case, 10 to 50 ° C., preferably 20 to
Development can be carried out at a temperature of 40 ° C. using a commercially available developing machine or ultrasonic cleaning machine.

The component (A) used in the photosensitive resin composition of the present invention is as described above.

The compound having an epoxy group as the component (B) is blended as a thermosetting component in order to thermally crosslink with the carboxyl group which is the acid anhydride residue of the component (A). Examples of the component (B) include phenol novolac type epoxy resin, cresol novolac type epoxy resin, bisphenol A type epoxy resin, bisphenol F type epoxy resin, bisphenol S type epoxy resin, biphenyl type epoxy resin, alicyclic epoxy resin. And a low molecular weight compound such as phenyl glycidyl ether, p-butylphenol glycidyl ether, triglycidyl isocyanate, diglycidyl isocyanurate, allyl glycidyl ether, and glycidyl methacrylate.

Examples of the photopolymerization initiator of the component (C) include acetophenone, 2,2-diethoxyacetophenone, p-dimethylacetophenone, p-dimethylaminopropiophenone, dichloroacetophenone, trichloroacetophenone and p-tert-. Acetophenones such as butylacetophenone, benzophenones, 2-chlorobenzophenone, benzophenones such as p, p′-bisdimethylaminobenzophenone, benzyl, benzoin, benzoin methyl ether, benzoin isopropyl ether, benzoin isobutyl ethers, and benzoin ethers, benzyl Dimethyl ketal, thioxanthone, 2-chlorothioxanthone, 2,4-diethylthioxanthone, 2-methylthioxanthone, 2-
Sulfur compounds such as isopropylthioxanthone, 2-
Ethyl anthraquinone, octamethyl anthraquinone,
1,2-benzanthraquinone, anthraquinones such as 2,3-diphenylanthraquinone, organic peroxides such as azobisisobutylnitrile, benzoyl peroxide, cumene peroxide, 2-mercaptobenzimidazole, 2-mercaptobenzoxazole, 2 −
Examples thereof include thiol compounds such as mercaptobenzothiazole. These compounds can also be used in combination of two or more kinds.

Although the photosensitive resin composition does not have a photopolymerization initiating action by itself, the ability of the photopolymerization initiator can be improved by using it in combination with the above photopolymerization initiator. A sensitizer can also be added. Examples of such sensitizers include tertiary amines such as triethanolamine, which are effective when used in combination with benzophenone.

In the photosensitive resin composition of the present invention, the mixing ratio of each component is 5 to 50 parts by weight, preferably 10 to 30 parts by weight with respect to 100 parts by weight of the component (A). The component (C) is 0.1 to 30 parts by weight, preferably 1 to 20 parts by weight. This is because when the mixing ratio of the component (B) is less than 5 parts by weight relative to 100 parts by weight of the component (A), the characteristics after curing of the photosensitive resin composition, particularly the alkali resistance becomes insufficient, and 50 parts by weight. If it exceeds, cracks will occur during curing and the adhesiveness will also decrease. Further, when the blending ratio of the component (C) is less than 0.1 parts by weight relative to 100 parts by weight of the component (A), the photopolymerization rate is excessively lowered, and the sensitivity is greatly lowered.
If it exceeds 0 parts by weight, it becomes difficult for light to reach the depth direction of the film made of the photosensitive resin composition, so that the curing reaction in the film on the non-irradiated side of the light does not sufficiently proceed, This is because the adhesion between the substrate and the substrate on which it is formed is reduced.

Further, in the photosensitive resin composition of the present invention,
Further, if necessary, additives such as an epoxy group curing accelerator, a thermal polymerization inhibitor, a plasticizer, a leveling agent, and a defoaming agent can be added. Here, examples of the epoxy group curing accelerator include amine compounds, imidazole compounds, carboxylic acids, phenols, quaternary ammonium salts, and methylol group-containing compounds. By using these epoxy group curing accelerators, various properties such as heat resistance, solvent resistance, acid resistance, plating resistance, adhesion, electrical properties and hardness of the resulting resist film can be improved. Further, as the thermal polymerization inhibitor, hydroquinone, hydroquinone monomethyl ether, pyrogallol, te
Examples include rt-butylcatechol and phenothiazine. Further, examples of the plasticizer include dibutyl phthalate, dioctyl phthalate, tricresyl and the like. Examples of the defoaming agent or leveling agent include silicone-based surfactants, fluorine-based surfactants, acrylic resins and the like. Further, if necessary, known fillers such as barium sulfate, silicon oxide, talc, clay, calcium carbonate, and known coloring pigments such as phthalocyanine blue, phthalocyanine green, titanium oxide, carbon black, etc. may be added. You can also

The photosensitive resin composition of the present invention is produced by uniformly mixing each of the components (A), (B) and (C) with, if necessary, other components according to a conventional method. You can

The photosensitive resin composition of the present invention can be used as follows.

For example, first, the photosensitive resin composition of the present invention is diluted with a solvent (for example, ketones such as methyl ethyl ketone and methyl isobutyl ketone, and cellosolves such as methyl cellosolve, ethyl cellosolve, butyl cellosolve and cellosolve acetate). , Further, a photopolymerization initiation aid,
A resist solution is prepared by adding additives such as a coupling agent and an antioxidant. Next, the resist composition is made into a resin composition solution 1 by an arbitrary method (for example, a solution dipping method, a spray method, a roller coater method, a spin coating method, etc.).
It is applied to a printed circuit board or the like in a thickness of about 30 μm. Then, in order to remove the solvent, a pre-cure treatment is carried out, thereby forming a film. Alternatively, a film is formed by attaching a dry film made of the photosensitive resin composition of the present invention to the surface of a printed circuit board or the like. Then, overlay a negative film on this film and use it as a light source (eg, ultra-high pressure mercury lamp, high pressure mercury lamp, metal halide lamp).
Is exposed to the active light from, and the unexposed portion is removed (developed) with an alkali developing solution and patterned. Thereby, a resist pattern can be produced from the photosensitive resin composition.

After the alkali development, post-curing (for example, 80 to 200 ° C./10 to 120 minutes) is necessary as a heat curing treatment in order to improve the alkali resistance of the film. As a result, not only the durability against strong alkaline water is remarkably improved, but also various properties required for the solder resist such as adhesion to metals such as glass and copper, heat resistance, and surface hardness are improved.

[0044]

The photosensitive resin of the present invention has a hydroxyl group of a bisphenol type epoxy resin which is first reacted with an unsaturated isocyanate compound to introduce an unsaturated isocyanate residue into the bisphenol type epoxy resin. Reaction of (meth) acrylic acid with the terminal epoxy group (meth)
A novel bisphenol-type epoxy acrylate resin is obtained by forming an acrylate group and a hydroxyl group, and the hydroxyl group formed on this novel bisphenol-type epoxy acrylate resin is subjected to an addition reaction with a polybasic acid intramolecular anhydride to give multiple It is produced by introducing a basic acid intramolecular anhydride residue. What is significantly different from the conventional method is that the raw material bisphenol type epoxy resin is modified with an unsaturated isocyanate compound. Therefore, a photosensitive resin composition containing this photosensitive resin shows excellent characteristics (resolution, heat resistance, electrical characteristics, mechanical characteristics, etc.) as a solder mask material, while being developable in an alkaline aqueous solution, It also has excellent storage stability.

[0045]

EXAMPLES The present invention will be specifically described below with reference to examples.

In the following Examples and Comparative Examples, "part" means "part by weight".

Example 1 In a 300 ml four-necked flask, 45 g of bisphenol A type epoxy resin of formula (2) (n = 2.0, trade name Epicoat 1001, manufactured by Yuka Shell Epoxy Co.) and 1 g of dibutyltin diacetate. And dry methyl isobutyl ketone 45
and g, and the mixture was heated and stirred at 70 ° C. under a nitrogen stream to give a uniform solution.

Next, the solution of the compound of formula (3) (R
A solution of 43 g of ( ⁴ = methyl group) and the same amount of dry methyl isobutyl ketone was added dropwise over 1 hour. Then, heating and stirring were continued until the absorption characteristic of the isocyanate group disappeared on the IR spectrum, whereby the bisphenol A type photosensitive epoxy resin (R ⁴ = methyl group) of the formula (4) was converted into a colorless transparent 50% methyl group. Obtained as an isobutyl ketone solution.

A 300 ml four-necked flask was charged with 177 g of a solution of the bisphenol A type photosensitive epoxy resin of the formula (4) in methyl isobutyl ketone, and a catalytic amount of p was added.
-Methoxyphenol and catalytic amount of benzyltriethylammonium chloride were added and stirred under an air stream with stirring 1
The temperature was raised to 10 ° C., and while maintaining the temperature, a methyl isobutyl ketone solution (14.4 g) containing 7.2 g of acrylic acid (R ³ = hydrogen) of the formula (5) was added dropwise over 1 hour. The stirring was continued at 110 ° C. for about 10 hours. Then, the acid value of the reaction system was reduced to about 1 to obtain the bisphenol A type epoxy acrylate of the formula (6) as a 50% methyl isobutyl ketone solution.

Further, a solution of bisphenol A type epoxy acrylate of formula (6) in methyl isobutyl ketone 19
1.4 g was charged into a 300 ml four-necked flask, 16 g of tetrahydrophthalic anhydride and 16 g of methyl isobutyl ketone were added, the temperature was raised to 110 ° C. with stirring, and stirring was continued for 3 hours while maintaining the temperature. , Formula (1)
Of the photosensitive resin ^{(R 1 = R 2 = R} 3 = hydrogen, X = -C (CH _3)
2 - to obtain Y = 3- acryloyloxy ethyl butoxycarbonyl amino-2-tolyl isocyanate residue, a compound with Z = Example 1 of tetrahydrophthalic anhydride residue) as a 50% methyl isobutyl ketone solution. The acid value of the obtained compound was 61 mgKOH / g (theoretical value: 57 mgKO
H / g).

Example 2 Example of photosensitive resin of formula (1) (Z = pyromellitic anhydride residue) in the same manner as in Example 1 except that pyromellitic dianhydride was used instead of tetrahydrophthalic anhydride. Two
Was obtained. The acid value of the obtained compound is 168 mgK
It was OH / g (theoretical value: 160 mgKOH / g).

Example 3 The same formula (1) was used as in Example 1 except that hexahydrophthalic anhydride was used instead of tetrahydrophthalic anhydride.
The compound of Example 3 was obtained as the photosensitive resin of (Z = hexahydrophthalic anhydride residue). The acid value of the obtained compound was 60 mgKOH / g (theoretical value: 57 mgKOH / g).

Example 4 A photosensitive resin of the formula (1) (Z = phthalic anhydride residue) was prepared in the same manner as in Example 1 except that phthalic anhydride was used instead of tetrahydrophthalic anhydride. The compound was obtained. The acid value of the obtained compound was 62 mgKOH / g (theoretical value: 57 mgKOH / g).

Example 5 Example 1 except that methylendomethylenetetrahydrophthalic anhydride is used instead of tetrahydrophthalic anhydride.
The compound of Example 5 was obtained as a photosensitive resin of the formula (1) (Z = methylendomethylenetetrahydrophthalic anhydride residue) in the same manner as in. The acid value of the obtained compound is 105 mg.
It was KOH / g (theoretical value: 109 mg KOH / g).

Comparative Example 1 Instead of the bisphenol A type epoxy resin of the formula (2) used in Example 1, a resin having an average degree of polymerization n of 0.1 (Epicoat 282, manufactured by Yuka Shell Epoxy Co., Ltd.) was used. A compound of Comparative Example 1 was obtained as a photosensitive resin of the formula (1) in the same manner as in Example 1 except for the above. The acid value of the obtained compound was 180 mgKOH / g (theoretical value: 183 mgKOH
/ G).

Comparative Example 2 Instead of the bisphenol A type epoxy resin of the formula (2) used in Example 1, a resin having an average degree of polymerization n of 8.8 (Epicoat 1007, manufactured by Yuka Shell Epoxy Co., Ltd.) was used. A compound of Comparative Example 1 was obtained as a photosensitive resin of the formula (1) in the same manner as in Example 1 except for the above. The acid value of the obtained compound was 22 mgKOH / g (theoretical value: 19 mgKOH /
g).

Examples 6-10 and Comparative Examples 3-4 40 parts of a solution of the photosensitive resin obtained in Examples 1-5 or the resin obtained in Comparative Examples 1-2 in methyl isobutyl ketone,
By uniformly mixing 5 parts of an alicyclic epoxy resin (EH-3150, manufactured by Daicel Chemical Co., Ltd.), 2 parts of a photopolymerization initiator (Darocur-1173, manufactured by Ciba Geigy), and 5 parts of methyl isobutyl ketone with alkali, A development type photosensitive resin composition (resist solution) was prepared.

Next, these resist solutions were applied to a degreased and washed copper-clad glass epoxy substrate to a dry thickness of about 50 μm and dried.

With respect to this dried film, a 500 W high pressure mercury lamp was used through a photomask to obtain 500 mJ /
Contact exposure was performed at an energy density of cm ² .

After exposure, the resist film was developed with a 1% aqueous solution of iminodiethanol at 25 ° C. for 1 minute to remove the unexposed portion. Then, post-curing (heat curing) was performed at 200 ° C. for 1 hour in a drying oven to obtain a patterned resist film.

The obtained resist film was tested and evaluated for "heat resistance", "adhesion to substrate", "developability" and "dryness to touch (tackiness)" as described below. Table 1 shows the results.

(1) "Heat Resistance" Test A resist film formed by heat curing after exposure and development was 250
It was kept in an oven at ℃ for 2 hours, and the state of the resist film was visually evaluated according to the following evaluation criteria.

Heat resistance evaluation standard rank Condition ◯: No abnormality X: When the resist film is cracked, peeled or colored.

(2) "Substrate adhesion" test A resist film formed by heating and curing after exposure and development was applied to 10
A cross cut was inserted so as to make 0 bases, and a cellotape peeling test of the cut surface was performed and evaluated according to the following evaluation criteria.

Substrate Adhesion Evaluation Criteria Rank State A: No peeling at all X: Peeling at all.

(3) "Developability" Test The state of development after exposure was visually evaluated according to the following evaluation criteria.

Developability Evaluation Criteria Rank State A: When good development is possible X: At least a part of the unexposed area is not dissolved, or at least a part of the exposed area is dissolved.

(4) "Dry to touch (tack)" and "storage stability" test The test piece after applying the resist solution was subjected to 65% RH at 50 ° C.
After being left in the constant humidity and constant temperature for 1 hour, the tackiness of the coating film was evaluated with a finger according to the following evaluation criteria.

Touch dryness (tackiness) evaluation standard rank condition ○: When tack is not recognized ×: When tack is recognized

[0070]

[Table 1] Example Photosensitive resin Heat resistance Substrate adhesion Developability Touch dryness 6 Example 1 ○ ○ ○ ○ 7 7 Example 2 ○ ○ ○ ○ ○ 8 Example 3 ○ ○ ○ ○ 9 Example 4 ○ ○ ○ ○ 10 Example 5 ○ ○ ○ ○ Comparative Example 3 Comparative Example 1 ○ ○ × × 4 Comparative Example 2 ○ ○ × ○ As can be seen from Table 1, the photosensitive resin compositions of Examples 6 to 10 have all the evaluation items. The excellent result was shown.

On the other hand, in the resin compositions of Comparative Examples 3 and 4, the unexposed areas were not dissolved during development and the alkali developability was unsatisfactory. Further, the resin composition of Comparative Example 3 was also unsatisfactory in the dryness to the touch.

[0072]

EFFECTS OF THE INVENTION According to the present invention, a coating film which can be developed with an alkaline aqueous solution and which exhibits excellent properties (resolution, heat resistance, electrical properties, mechanical properties, etc.) as a solder mask material and which has been pre-cured A photosensitive resin composition that is tack-free can be prepared. This photosensitive resin composition can be used in a wide range of fields as an etching resist for a printed wiring board, an interlayer insulating material, a photosensitive adhesive, a paint, a photosensitive liquid for screen printing, a resist ink, and the like.

Claims (15)

[Claims] 1. Formula (1): (In the formula, R ¹ and R ² are each independently hydrogen, a lower alkyl group or halogen, R ³ is hydrogen or a methyl group, X is absent or —CO—, —SO ₂ —, —
_{C (CF 3) 2 -,} - Si (CH 3) 2 -, - C (CH 3) 2 - or a -O-, Y is an unsaturated isocyanate residue, Z is a multi saturated or unsaturated It is an anhydride residue in the basic acid molecule, and the average degree of polymerization n is a number of 0.5 to 5. ) A photosensitive resin represented by. 2. The photosensitive resin according to claim 1, wherein the unsaturated isocyanate residue of Y is a hydrocarbon group having a (meth) acroyloxyalkoxycarbonylamino group. 3. The photosensitive resin according to claim 2, wherein the (meth) acroyloxyalkoxycarbonylamino group is an acroyloxyethoxycarbonylamino group or a metacroyloxyethoxycarbonylamino group. 4. The photosensitive resin according to claim 2, wherein the hydrocarbon group contained in the unsaturated isocyanate residue of Y is an alkyl group, an aryl group or an alicyclic alkyl group. 5. The hydrocarbon group contained in the unsaturated isocyanate residue of Y is hexyl group, phenyl group, toluyl group, xylyl group, naphthyl group, phenylmethylphenyl group, hydrogenated xylyl group or isophorone-yl. The photosensitive resin according to claim 4, which is a group. 6. The photosensitive resin according to claim 1, wherein the saturated or unsaturated polybasic acid intramolecular anhydride residue of Z is a hydrocarbon group having a carboxyl group. 7. The hydrocarbon group contained in the saturated or unsaturated polybasic acid intramolecular anhydride residue of Z is an alkyl group, an alkenyl group, an aryl group or an alicyclic alkyl group. Photosensitive resin. 8. R ¹ and R ² are hydrogen and X is —C (C
H _{3) 2} - a photosensitive resin according to any one of claims 1 to 7. 9. The photosensitive resin according to claim 1, which has an acid value of 30 to 150 mg KOH / g. 10. The photosensitive resin according to claim 1, which comprises the following components (A), (B) and (C) (A).
100 parts by weight (B) Compound having at least one epoxy group in the molecule 5 to 50 parts by weight (C) Photopolymerization initiator 0.1 to 30 parts by weight A photosensitive resin composition characterized by containing . 11. Formula (A): (In the formula, R ¹ and R ² are each independently hydrogen, a lower alkyl group or halogen, R ³ is hydrogen or a methyl group, X is absent or —CO—, —SO ₂ —,
_{-C (CF 3) 2 -,} - Si (CH 3) 2 -, - C (CH 3) 2 - or a -O-, Y is an unsaturated isocyanate residue, an average degree of polymerization n is 0 It is a number from 0.5 to 5. ) A bisphenol type epoxy acrylate resin represented by. 12. The bisphenol type epoxy acrylate resin according to claim 11, wherein the unsaturated isocyanate residue of Y is a hydrocarbon group having a (meth) acroyloxyalkoxycarbonylamino group. 13. The bisphenol type epoxy acrylate resin according to claim 12, wherein the (meth) acroyloxyalkoxycarbonylamino group is an acroyloxyethoxycarbonylamino group or a metacroyloxyethoxycarbonylamino group. 14. The bisphenol type epoxy acrylate resin according to claim 12, wherein the hydrocarbon group contained in the unsaturated isocyanate residue of Y is an alkyl group, an aryl group or an alicyclic alkyl group. 15. The hydrocarbon group contained in the unsaturated isocyanate residue of Y is hexyl group, phenyl group, toluyl group, xylyl group, naphthyl group, phenylmethylphenyl group, hydrogenated xylyl group or isophorone-yl. The bisphenol type epoxy acrylate resin according to claim 14, which is a group.