JPS62153308A - Photopolymerizable curable composition - Google Patents

Abstract

PURPOSE:To obtain the title composition excellent in resistance to treatment such as etching after development or metal plating, by mixing a specified thermoplastic polymer binder with an addition-polymerizable compound and a photoinitiator (system). CONSTITUTION:A thermoplastic polymer binder (a) is obtained by copolymerizing 4-40wt% COOH group-containing addition-polymerizable monomer (e.g., methacrylic acid) with at least 5wtT nonacidic addition-polymerizable monomer (B) such as a methacrylate of formula I (wherein R1 is H or CH3, R2 is a 1-5C alkylene, R3 is H, a 1-5C alkyl or a halogen and n is 1-20) and a nonacidic addition-polymerizable monomer (a) having Q and e values satisfying the relationship of formula II (wherein QA and eA are the Q and e values of addition polymerizable monomer A and QC and eC are those of component C). 100pts.wt. component (a) is mixed with 10-200pts.wt. addition- polymerizable compound (b) having an atmospheric b.p. >=50 deg.C (e.g., trimethylolpropane triacrylate) and 0.01-30pts.wt. photoinitiator and/or photoinitiator system (c) (e.g., benzophenone).

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a photopolymerizable composition that is cured by irradiation with light and developable with an alkaline aqueous solution. More specifically, the present invention relates to a photopolymerizable curable composition that has improved resistance to treatments such as etching and plating after development.

[Conventional technology and problems]

In general, photopolymerized cured products are laminated by coating, laminating, etc. on a substrate, such as a copper-clad laminate or a metal surface to be subjected to microfabrication, and when exposed to active light, the exposed areas are cured.
The unexposed areas are dissolved and removed with a solvent having appropriate solubility.

Solvents can be broadly divided into 1, 1, 1. -) Some use organic solvents such as dichloroethane, and others use aqueous solvents such as aqueous sodium carbonate.

In recent years, photopolymerizable curable compositions that are developed using aqueous solvents have been increasingly used in view of work environment, surrounding environment, and manufacturing cost.

However, compared to the case of using a conventional organic solvent-developable photopolymerizable composition, there are many restrictions on etching and plating processes, which often causes problems during use.

[Means for solving problems]

As a result of intensive studies to solve these problems, the inventors of the present invention found that a thermoplastic polymer binder of addition polymerizable compound type obtained by copolymerizing addition polymerizable monomers with a specific structure is used to improve resistance. The present invention has been achieved based on the discovery that this can be improved.

That is, the present invention provides: (1) an addition polymerization monomer (A) having a carboxyl group;
~40 weight percent and the following non-acidic addition polymerized monomers (
Non-acidic addition-polymerized monomer (B) is added to 100 parts by weight of a thermoplastic polymer binder obtained by copolymerizing at least 5% by weight of B) with the following non-acidic addition-polymerized monomer (C). ) The acrylic ester represented by the secondary general formula (1) is at least one R of methacrylic ester monomers.

(R is a hydrogen atom or a methyl group, R2 is an alkylene group having 1 to 5 carbon atoms, R3 is a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, a halogen atom, n is an integer from 1 to 20) Non-acidic addition polymerization monomer (C): At least one non-acidic addition polymerization monomer A having a Q value and an e value satisfying the following formula (II) 0.25<-EXP (-eA(eA-ec )
) <4.00 (II)c (Q, +eA is the Q value and e value of the addition polymerization monomer (A),
QC+eC is the Q value and e value of the addition polymerizable monomer (C)) (2) 10 to 200 parts by weight of an addition polymerizable compound having a boiling point of 50°C or higher at normal pressure; (3) a photoinitiator and/or The present invention relates to a photopolymerizable and curable composition comprising 0.01 to 30 parts by weight of a photoinitiator system.

First, the thermoplastic polymer binder used in the present invention will be explained in detail. In the addition-polymerizable compound type photopolymerizable curable composition according to the present invention, the resistance of the resist film largely depends on the properties of the polymeric binder. The acidic addition polymerization monomer (A) having a carboxyl group in the copolymer forming the polymeric binder of the present invention imparts developability to the copolymer, and its proportion in the copolymer composition is The range is from 4 to 40 weight percent. The appropriate ratio varies depending on the type of developer, and for example, a range of 4 to 15 weight percent for a so-called semi-aqueous solution development type containing ethylene glycol monobutyl ether, and 15 to 40 weight percent for a fully aqueous solution development type is a tentative guideline. can do. Of course, the optimum copolymerization rate of acidic addition polymerizable monomers, whether semi-aqueous or fully aqueous, varies depending on the developer and development conditions. In the present invention, the addition polymerization monomer (A) having a carboxyl group includes:
Preference is given to methacrylic acid and mixtures of methacrylic acid and acrylic acid.

Since such an acidic addition polymerization monomer is copolymerized, the thermoplastic polymer binder essentially swells and dissolves in an alkaline liquid. Therefore, it is essential to copolymerize a non-acidic addition monomer in order to impart resistance. In particular, the non-acidic addition polymerization monomer (B), which is an acrylic ester or methacrylic ester having a specific structure, is effective for improving the resistance to alkaline aqueous solutions.

Examples of these include #2-phenoxyethyl acrylate, 2-phenoxyethyl methacrylate, 2-phenoxypropyl acrylate, 3-phenoxypropyl acrylate, phenoxyjethoxy acrylate, phenoxytriethoxy acrylate, and phenoxyethyl acrylate. Cidiproboxy, P-chlorophenoxyethyl acrylate, P-methylphenoxyethyl acrylate, methacrylic acid 2
-Phenoxypropyl, 3-phenoxypropyl methacrylate, phenoxyjethoxy methacrylate, phenoxytriethoxy methacrylate, phenoxydipropoxy methacrylate, P-chlorophenoxyethyl methacrylate, P-methylphenoxyethyl methacrylate, etc. However, it is not limited to these.

These non-acidic addition polymerization monomers (B) must be contained in the copolymer in an amount of at least 5% by weight or more.

The non-acidic addition polymerization monomer (C) is the addition polymerization monomer (B)
Together with this, it serves as a component that imparts resistance, but in addition, it also plays a role in controlling the glass transition point (Tg) of the copolymer. The preferred copolymer Tg is between 40"C and 120C, and 4
At temperatures below 0°C, when the photosensitive layer is used as a "dry film" in which the photosensitive layer is sandwiched between a support film and a protective film, a "cold flow" phenomenon occurs in which the photosensitive layer flows over time, and at temperatures above 120°C, the photosensitive layer The adhesion of the substrate is significantly impaired.

Furthermore, the non-acidic addition polymerization monomer (C) has the effect of forming a copolymer in which the acidic addition polymerization monomer (A) is polymerized as uniformly within and between molecules as possible. If the acidic addition-polymerized monomer is not uniformly polymerized, not only will it cause poor development of the cured composition, but in severe cases, the copolymer will precipitate during polymerization, and the copolymer will deteriorate when the coating solution is mixed. A precipitate forms. Such a non-acidic addition polymerization monomer (C) is determined depending on the acidic addition polymerization monomer (A).

For example, methacrylic acid (QA=
2.340. eA = 0.650), methyl methacrylate (Qc = 0.740.e
c=0.400.

0^ -exp (-ea(eA-ec) l-2,69)
, Methac C A ethyl lylate (Qc = 0.730. eC = 0.52
0, □c exp (-eA(eA-ec)) = 2.95). In this case, acrylic 9n-butyl (Qc -0,500, e-=1.060, 2ex
pLeA(eA-C-ec)) = 6.11), methacrylic acid is rapidly consumed during polymerization, resulting in a non-uniform copolymer composition and, in some cases, precipitation.

In addition, when using a plurality of acidic addition polymerization monomers (A) in the present invention, the non-acidic addition polymerization monomer (C) is combined with at least one acidic addition polymerization monomer (A) among them. The above equation (n) is satisfied between the two.

Next, at normal pressure, 50
Examples of addition polymerizable compounds having a boiling point of ℃ or higher include styrene compounds such as styrene, α-methylstyrene, and chlorostyrene, and methyl (meth)acrylate (
Means methyl acrylate and methyl methacrylate.

(hereinafter similarly abbreviated), ethyl (meth)acrylate, n-
and i-propyl (meth)acrylate, n-, sec
- and t-butyl (meth)acrylate, tetrahydrofurfuryl (meth)acrylate, 2-ethylhexyl (meth)acrylate, lauryl (meth)acrylate, stearyl (meth)acrylate, butoxyethyl (meth)acrylate, cyclohexyl (meth)acrylate , monofunctional (meth)acrylate compounds such as phenoxyethyl (meth)acrylate, methoxyethyl (meth)acrylate, ethoxyethyl (meth)acrylate, polyethylene glycol (meth)acrylate, polypropylene glycol (meth)acrylate, (meth)acrylonitrile, Also, (meth)acrylamide,
(meth) such as N-methylol (meth)acrylamide
Acrylamides, ethylene glycol di(meth)acrylate, diethylene glycol di(meth)acrylate, triethylene glycol di(meth)acrylate,
Propylene glycol di(meth)acrylate, dipropylene glycol di(meth)acrylate, polyprolene glycol di(meth)acrylate, polyethylene glycol di(meth)acrylate, 1,4-butanediol di(meth)acrylate, neopentyl glycol di(meth)acrylate (meth)acrylate, trifunctional (meth)acrylates such as 1,6-hexanediol di(meth)acrylate, trimethylolpropane tri(meth)acrylate, trimethylolethanetri(meth)acrylate, pentaerythritol tetra(meth)acrylate Trifunctional or higher functional (meth)acrylates such as acrylates, di(meth)acrylates of ethylene oxide and/or propylene oxide adducts of bisphenol A, di(meth)acrylates of ethylene and/or propylene oxide adducts of hydrogenated bisphenol A Trifunctional (meth)acrylates such as, N,N'-methylenebis(meth)acrylamide, bisacrylamides such as N,N'-benzylidenebis(meth)acrylamide, etc.
It is not limited to these. In the composition of the present invention, these addition polymerizable compounds are added to the thermoplastic polymeric binder 1.
It is contained in an amount of 10 to 200 parts by weight per 00 parts by weight.

Photoinitiators and/or photoinitiator systems that can be used in the compositions of the invention include the following.

That is, there are substituted or unsubstituted polynuclear quinones, such as 2
-ethylanthraquinone, 2-tert-butylanthraquinone, octamethylanthraquinone, 1,2-henzuanthraquinone, 2,3-henzuanthraquinone, 2
-Phenylanthraquinone, 2.3-diphenylanthraquinone, 1-chloroanthraquinone, 2-chloroanthraquinone, 2-methylanthraquinone, 1.4-natsutaquinone, 9.10-phenylanthraquinone, 2-methyl-1,4-natsutaquinone , 2.3-dichloronatsutaquinone, 1.4-dimethylanthraquinone, 2.3-dimethylanthraquinone, 3-chloro-2-methylanthraquinone, 7,8,9. Examples include to-tetrahydrophthasenginone. Other aromatic ketones include hensifhenone, Michler's ketone L4+4'-bis(dimethylamino)hensiphenone, 4.4"-bis(diethylamino)benzophenone, 4-methoxy-4'-dimethylaminobenzophenone, etc. Benzoin, benzoin ether, such as benzoin methyl ether, penzoin dielether, benzoin phenyl ether, methylbenzoin, ethylbenzoin, etc.Furthermore, 2.4.,5-triarylimidazole dimer and 2-mercaptobenzoxazole. , leucocriscle hiolesotho, tris(4-diethylamino-2=methylphenyl)methane, etc. can also be used in combination.

In addition, there are substituted or unsubstituted thioxanthone, such as 2-chlorothioxanthone, 2.4-diethylthioxanthone, 2,4-dimethylthioxanthone, and the like. Furthermore, combinations of these thioxanthones with aliphatic or aromatic tertiary amines, such as N-methyljetanolamine, P-dimethylaminobenzoic acid ethyl ester, etc., can also be used. Combinations with Michler's ketone and thioxanthones with oxime esters such as benzophenone oxime acetate are also effective. These addition polymerization initiators that can be activated by light may be used alone or in combination. Note that the present invention is not limited to these.

These are 0 parts per 100 parts by weight of thermoplastic polymer binder.
．． It can be used in an amount of 0.01 to 30 parts by weight, preferably 0.1 to 15 parts by weight.

In the present invention, in addition to the above-mentioned essential elements, stabilizers, dyes, etc. can be added as necessary. Examples of the stabilizer include hydroquinone, hydroquinone monomethyl ether, and t-butylcatechol. These can be added within a range that does not inhibit the photopolymerization reaction. Plasticizers can also be added to impart appropriate flexibility. For example, phthalic acid esters such as diethyl phthalate, dibutyl phthalate, diethyl phthalate, and dioctyl phthalate, fatty acid esters such as dioctyl adipate and dibutyl diglycol adipate, phosphoric acid esters such as trimethylphosphine, and sulfonic acids such as toluenesulfonamide. Examples include amides.

Additionally, dyes may be added to facilitate visual identification of the photosensitive layer. Examples include crystal violet, malachite green, Victoria blue, and methylene blue.

In the present invention, when the photopolymerizable curable composition is solvent-free, it is usually coated or impregnated onto a suitable support using a printing method or a coating method when it is dissolved or dispersed in a solvent, and then A photopolymer layer can be formed by one shot of a solvent.

The support in this case may be any material as long as it does not adversely affect the photopolymerization, and examples thereof include various plastics, various films, paper, glass, various metals, and ceramic products.

Such photopolymer layers are cured by light from a suitable light source, such as a low pressure mercury lamp, a high pressure mercury lamp, or the like. The composition of the present invention can be used as a photopolymer or photoresist when producing a printing plate printed circuit board or the like.

(Example〕 Next, the present invention will be specifically explained using examples.

Note that the present invention is not limited in any way to the embodiments.

Synthesis Example of Thermoplastic Polymer Binder The following addition polymerization monomers were polymerized to obtain a thermoplastic polymer binder solution.

A liquid methacrylic acid 250 g Methyl methacrylate 350 g 2-phenoxyethyl acrylate 50 g B; night α, α゛-azobis-1so-butyronitrile g Tetrahydrofuran 250 g A dropping funnel containing liquids A and B, a reflux condenser tube, a nitrogen introduction tube, 10 in a 51 separable flask equipped with a stirring bar
00 g of methyl ethyl ketone was added and heated to 75°C. Next, both solutions A and B were added dropwise over a period of 3 hours, and stirring was continued while maintaining the temperature at 75°C for an additional 8 hours. A clear resin solution was obtained.

Synthesis comparison example An attempt was made to polymerize the following addition-polymerizable monomers.

A? 250 g of methacrylic acid 350 g of n-butyl acrylate 50 g of 2-phenoxyethyl acrylate 50 g of α,α1-azobis-1so-butyronitrile 250 g of tetrahydrofuran Polymerization was attempted in the same manner as in Example I, but the reaction solution became cloudy while polymerization started. However, it was not possible to obtain a uniform resin solution due to the formation of precipitates and entanglement with the stirring bar.

Example 1 A photopolymerizable and curable composition was obtained by mixing the following components.

Trimethylolpropane triacrylate 0 g Hensiphenone 1.5 g Michler's ketone 0.15 g Victoria Blue 0.05 g Methyl ethyl ketone
80g of this was coated on a polyethylene glycol terephthalate film support with a thickness of 25I1m.
It was dried at ℃ to obtain a photosensitive film. The thickness of the photosensitive layer is 25
It was ρ. This was applied to a polished copper clad laminate at 100°C.
Laminated with a heated rubber roller. Place a wiring circuit pattern mask on top and use an ultra-high pressure mercury lamp to illuminate 50cm.
Irradiate for 10 seconds from a distance of 1% at 30℃ after curing.
When developed with an aqueous sodium carbonate solution, a resin relief image was obtained on the copper-clad laminate.

Next, copper was etched using an alkaline etchant, and a good printed wiring board was obtained.

Example 2 A photopolymerizable and curable composition was obtained by mixing the following components.

Trimethylolpropane triacrylate 0 g Benzophenone 1.5 g Michler's Ketone 0.15 g Victoria Blue
0.05g methyl ethyl ketone
80 g As a result of evaluation in the same manner as in Example 1, a good printed wiring board was obtained.

Example 3 A photopolymerizable and curable composition was obtained by mixing the following components.

Trimethylolpropane triacrylate 0 g 2-chlorothioxanthone 0.5 g Methyljetanolamine 0.05 g Victoria Blue
0.05g methyl ethyl ketone
80 g As a result of evaluation in the same manner as in Example 2, a good printed wiring board was obtained.

Comparative example 1 A photopolymerizable and curable composition was obtained by mixing the following components.

Trimethylolpropane triacrylate 0 g 2-chlorothioxanthone 0.5 g Methyljetanolamine 0.05 g Victoria Blue
0.05g methyl ethyl ketone
80 g Evaluation was made in the same manner as in Example 2, but disconnections were observed in the excellent printed wiring board.

Comparative example 2 A photopolymerizable and curable composition was obtained by mixing the following components.

Trimethylolpropane triacrylate 0 g 2-chlorothioxanthone 0.5 g Methyljetanolamine 0.05 g Methyl ethyl ketone
80 g Evaluation was carried out in the same manner as in Example 2, but disconnections were observed in the obtained printed wiring board.

Claims (1)

[Claims] 1 (1) Addition polymerization monomer having a carboxyl group (A
Thermoplastic polymer bond formed by copolymerizing 4 to 40% by weight of the following non-acidic addition polymerization monomer (B) and at least 5% by weight or more of the following non-acidic addition polymerization monomer (C) Agent 1
00 parts by weight, non-acidic addition polymerization monomer (B): At least one acrylic ester or methacrylic ester monomer represented by the following general formula (I) ▲ Numerical formula, chemical formula, table, etc. ▼(I) (R1 is a hydrogen atom or a methyl group, R2 is an alkylene group having 1 to 5 carbon atoms, R3 is a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, a halogen atom, n is a 1 to 20 carbon atom, Integer) Non-acidic addition polymerization monomer (C): At least one non-acidic addition polymerization monomer having a Q value and an e value satisfying the following formula (II) 0.25<Q_A/Q_CEXP{-e_A(e_A −
e_C)}<4.00(II) (Q_A, e_A are the Q value and e value of the addition polymerization monomer (A), Q_C, e_C are the Q value and e value of the addition polymerization monomer (C)) ( 2) 10 to 200 parts by weight of an addition polymerizable compound having a boiling point of 50°C or higher at normal pressure; and (3) 0.01 to 30 parts by weight of a photoinitiator and/or a photoinitiator system. A photopolymerizable curing composition characterized by: 2. The photopolymerizable curable composition according to claim 1, wherein the addition polymerization monomer (A) having a carboxyl group is methacrylic acid alone or a mixture of methacrylic acid and acrylic acid.