JPS62153309A - Photocurable polymer 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 unsaturated compound or an addition- polymerizable compound containing this compound and a photopolymerization initiator (system). CONSTITUTION:A thermoplastic polymer binder (A) is obtained by copolymerizing a COOH group-containing adddition-plymerizable monomer (a) with a nonacidic addition-polymerizable monomer (b) such as an acrylate of formula I (wherein R1 is a 1-5 C alkylene and R2 is H, a 1-5 C alkyl or a halogen) and a nonacidic addition-polymerizable monomer (c) such as a 1-5 C alkyl methacrylate. 100pts.wt. component A is mixed with 20-200pts. wt. unsaturated compound (B) having at least three ethylenically unsaturated groups in the molecule, represented by formula II (wherein R1-3 are each H or CH3 and n is 1-6) and having a MW of 350-2000 or addition- polymerizable compound containing at least two pts.wt. above unsaturated compound and having an atmospheric b.p. >=50 deg.C and 0.01-30pts.wt. photoinitiator and/or photoinitiator system (C) (e.g., benzophenone).

Description

DETAILED DESCRIPTION OF THE INVENTION [4 Fields of Industrial Application] The present invention relates to a photopolymerizable curable 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.

The solvent can be roughly divided into those that use organic solvents such as 1,1,1-trichloroethane and those that use aqueous solvents such as aqueous sodium carbonate solution.

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 combines (1) an addition polymerization monomer (8) having a carboxyl group, the following non-acidic addition polymerization monomer (B), and the following non-acidic addition polymerization monomer (C). For 100 parts by weight of the polymerized thermoplastic polymer binder, non-acidic addition polymerization monomer (B): Acrylic acid ester CH2=CH represented by the following general formula (H (R, is carbon number 1) to 5 alkylene group, R2 is a hydrogen atom or a furkyl group having 1 to 5 carbon atoms, or a halogen atom) Non-acidic addition polymerization monomer (C): methacrylic acid alkyl ester consisting of an alkyl group having 1 to 5 carbon atoms (2) As an addition polymerizable compound, an unsaturated compound having a molecular weight of 350 to 2000 and having at least 3 or more ethylenically unsaturated groups in one molecule represented by the following formula (II), or containing at least 2 parts by weight or more of the compound 20 to 200 parts by weight of an addition polymerizable compound having a boiling point of 50°C or higher at normal pressure; ) A photocurable polymeric composition comprising: a photoinitiator and/or a photoinitiator system o, oi to 30 parts by weight.

First, the 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 (8) 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 polymeric binder is The range is from 4 to 40 weight percent. The appropriate ratio varies depending on the type of developer; for example, for a so-called semi-aqueous solution development type containing ethylene glycol monobutyl ether, it is 4 to 4.
15% by weight, 15~ for fully aqueous development type
A range of 40 weight percent can be used as a tentative guideline. 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, preferred examples of the addition polymerization monomer (A) having a carboxyl group include crotonic acid, itaconic acid, maleic acid, or anhydride thereof, maleic acid monoalkyl ester, fumaric acid, and fumaric acid monoalkyl ester. , p-vinylbenzoic acid, and these may be used alone or in combination.

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 having a specific structure, is effective for improving the resistance to alkaline aqueous solutions.

Examples of such are benzyl acrylate, phenethyl acrylate, 3-phenylbutyl acrylate,
Examples include, but are not limited to, 2-phenylbutyl acrylate, p-chlorobenzyl acrylate, p-ethylbenzyl acrylate, 2-phenylpropyl acrylate, and p-ethylbenzyl acrylate. .

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 Tg of the preferred copolymer is between 40°C and 120°C;
When used as a "dry film" in which the photosensitive layer is sandwiched between a support film and a protective film at temperatures below 40°C, "cold flow" occurs in which the photosensitive layer flows over time.
phenomenon occurs, and the adhesion of the photosensitive layer is significantly impaired at temperatures above 120°C.

Next, the addition polymerizable compound (2) to be added to the photocurable polymer composition of the present invention has a molecular weight of 350 to 2000 and has at least three ethylenically unsaturated groups represented by the general formula (n) in one molecule. Examples of unsaturated compounds include glyceryl ethoxy triacrylate, glyceryl propoxy trimethacrylate, glyceryl propoxy triacrylate, trimethylol propane ethoxy triacrylate, trimethylol propane propoxy triacrylate, pentaerythritol ethoxy triacrylate, pentaerythritol ethoxy tetraacrylate, pentaerythritol ethoxy triacrylate, Erythritol propoxy triacrylate, glyceryl jetoxy triacrylate, glyceryl triethoxy triacrylate, glyceryl dipropoxy triacrylate, glyceryl dipropoxy trimethacrylate, trimethylolpropane jetoxy triacrylate, trimethylolpropane dipropoxy triacrylate, pentaerythritol jetoxy triacrylate Acrylate, pentaerythritol triethoxy triacrylate, and pentaerythritol triethoxy trimethacrylate. In addition, an addition polymerizable compound (2
) may also be an addition polymerizable compound containing at least 2 parts by weight of these unsaturated compounds and having a boiling point of 50° C. or higher at normal pressure.

Examples of addition-polymerizable compounds having a boiling point of 50°C or higher at normal pressure include styrene compounds such as styrene, α-methylstyrene, and chlorostyrene;
meth) acrylate (means methyl acrylate and methyl methacrylate. The same abbreviation hereinafter), ethyl (
meth)acrylate, n- and i-propyl (meth)acrylate, n-,5ec- and t-butyl (meth)acrylate, tetrahydrofurfuryl (meth)acrylate, 2-ethylhexyl (meth)acrylate, lauryl (meth)acrylate , stearyl (meth)acrylate, butoxyethyl (meth)acrylate, cyclohexyl (meth)acrylate, phenoxyethyl (meth)acrylate, methoxyethyl (meth)acrylate, ethoxyethyl (meth)acrylate, polyethylene glycol (meth)acrylate, polypropylene glycol ( -functional (meth)acrylates, etc.
Acrylate compounds, (meth)acrylonitrile, and
(meth)acrylamide, (meth)acrylamides such as N-methylol (meth)acrylamide, ethylene glycol di(meth)acrylate, diethylene glycol di(meth)acrylate, triethylene glycol di(meth)acrylate, propylene glycol di(meth)acrylate 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, 1
．． Trifunctional (meth)acrylates such as 6-hexanethiol di(meth)acrylate, trifunctional or higher functional compounds such as trimethylolpropane tri(meth)acrylate, trimethylolethane tri(meth)acrylate, and pentaerythritol tetra(meth)acrylate. (meth)acrylates, di(meth) of ethylene oxide and/or propylene oxide adducts of bisphenol A
acrylate, trifunctional (meth)acrylate such as di(meth)acrylate of hydrogenated bisphenol A adduct with ethylene and/or propylene oxide, N,N'-methylenebis(meth)acryamide, N,N'-benzylidene bis(meth)acrylate, ) bisacrylamides such as acrylamide, but are not limited thereto.

In the composition of the present invention, the addition polymerizable compound (2) as described above is used in an amount of 20 to 200 parts by weight per 100 parts by weight of the thermoplastic polymeric binder.

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-benzanthraquinone, 2,3-benzanthraquinone, 2
-Phenylanthraquinone, 2,3-diphenylanthraquinone, 1-chloroanthraquinone, 2-chloroanthraquinone, 2-methylanthraquinone, 1,4-natsutaquinone, 9. IO-phenanthraquinone, 2-methyl-1,4-natsutaquinone, 2,3-dichloronatsutaquinone, 1,4-dimethylanthraquinone, 2,3-dimethylanthraquinone, 3-chloro-2-methylanthraquinone, 7, Examples include 8,9.10-tetrahydrophtacenequinone. Other aromatic ketones include benzophenone, Michler's ketone (4,4'-bis(dimethylamino)benzophenone), 4,4'-bis(diethylamino)benzophenone, 4-methoxy-4'-dimethylaminobenzophenone, etc. . Other examples include benzoin and benzoin ethers such as benzoin methyl ether, benzoin ethyl ether, benzoin phenyl ether, methylbenzoin, and ethylbenzoin. Furthermore, combinations of 2,4.5-triarylimidazole dimer and 2-mercaptobenzoxazole, leuco crystal violet, tris(4-diethylamino-2-methylphenyl)methane, etc. can also be used.

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 and P-dimethylaminobenzoic acid ethyl ester can also be used, as well as combinations of thioxanthones with alkylaminobenzophenones such as Michler's ketone. Combinations of thioxanthone and oxime ester 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, phthalate esters such as diethyl phthalate, dibutyl phthalate, diethyl phthalate, and dioctyl phthalate, fatty acid esters such as dioctyl adipate and dibutyl diglycol adibate, phosphoric esters such as trimethylphosphine, and sulfones such as toluenesulfonamide. Examples include acid amides.

In the present invention, when the photopolymerizable curable composition is solvent-free, it is usually applied by printing or coating, and when it is dissolved or dispersed in a solvent, it is applied or impregnated onto a suitable support. A photopolymer layer can be obtained by evaporating the solvent.

In this case, the support may be any material that does not give an adverse effect on photopolymerization (eg, various plastics, various films, paper, glass, various metals, ceramic products, etc.).

Such photopolymer layers are cured by light from a suitable light source, such as a low-pressure mercury lamp or an ultra-high pressure mercury lamp. 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.

Example 1 A photocurable polymer composition was obtained by mixing the following components.

Glyceryl propoxytriacrylate 0 g Benzophenone 1.5 g Michler's Ketone 0.15 g Victoria Blue
0.05g methyl ethyl ketone
80 g of this was coated on a 25-thick polyethylene glycol terephthalate film support and heated at 75°.
It was dried at C to obtain a photosensitive film. The thickness of the photosensitive layer is 25
-It was. This was laminated onto a copper-clad laminate that had been polished with a rubber roller heated to 100°C. Place a wiring circuit pattern mask on top and use an ultra-high pressure mercury lamp to illuminate 50cm.
The resin was irradiated for 10 seconds from a distance of 30° C., and then developed with a 1% sodium carbonate aqueous solution at 30° C. to obtain a resin relief image on the copper-clad laminate.

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

Example 2 A photocurable polymer composition was obtained by mixing the following components.

Trimethylolpropane jetoxytriacrylate
30 g hensifenone
1.5g Michler's Ketone
0.15g Victoria Blue 0.05
g Methyl ethyl ketone 80 g Example 1
When evaluated in the same manner as above, a good printed wiring board was obtained.

Example 3 A photocurable polymer composition was obtained by mixing the following components.

Glyceryl propoxy triacrylate 20 g Trimethylolpropane triacrylate 0 g 2-chlorothioxanthone 0.5 g Methyljetanolamine 0.05 g Victoria Blue
0゜05g methyl ethyl ketone
80 g When evaluated in the same manner as in Example 1, a good printed wiring board was obtained.

Comparative example 1 A photocurable polymer composition was obtained by mixing the following components.

Glyceryl propoxytriacrylate 0 g Hensiphenone 1.5 g Michler's Ketone 0.15 g Victoria Blue
0.05g methyl ethyl ketone
80 g Evaluation was carried out in the same manner as in Example 1, but disconnection was observed in the obtained printed wiring board.

Claims (1)

[Claims] 1 (1) Addition polymerization monomer having a carboxyl group (A
), the following non-acidic addition polymerized monomer (B), and the following non-acidic addition polymerized monomer (C) for 100 parts by weight of a thermoplastic polymer binder, Polymerization monomer (B): Acrylic ester represented by the following general formula (I) ▲ Numerical formula, chemical formula, table, etc. are available ▼ (I) (R_1 is an alkylene group with 1 to 5 carbon atoms, R_2
is a hydrogen atom, an alkyl group having 1 to 5 carbon atoms, or a halogen atom) Non-acidic addition polymerizable monomer (C): methacrylic acid alkyl ester (2) consisting of an alkyl group having 1 to 5 carbon atoms as an addition polymerizable compound An unsaturated compound having a molecular weight of 350 to 2,000 and having at least three ethylenically unsaturated groups in one molecule represented by the following formula (II), or a boiling point of 50°C or more at normal pressure containing at least 2 parts by weight or more of the compound 20 to 200 parts by weight of an addition polymerizable compound having ▲Mathematical formulas, chemical formulas, tables, etc.▼(II) (In the formula, R_1, R_2, R_3 are hydrogen atoms or methyl groups, and n is an integer from 1 to 6) (3) A photocurable polymer composition comprising: 0.01 to 30 parts by weight of a photoinitiator and/or a photoinitiator system. 2. The addition polymerization monomer (A) having a carboxyl group is crotonic acid, itaconic acid, maleic acid, or an anhydride thereof,
The photocurable polymer composition according to claim 1, which is at least one compound selected from monoalkyl maleate, fumaric acid, monoalkyl fumarate, and p-vinylbenzoic acid.