JPH03106903A - Photosensitive thermosetting resin composition solder resist resin composition, and cured product thereof - Google Patents

Abstract

PURPOSE:To obtain a photosensitive thermosetting resin composition which can be developed with a weakly alkaline aqueous solution and is improved in photocurability, heat resistance, etc., by mixing a prepolymer having a carboxyl and an ethylenically unsaturated group with a specified compound, a photopolymerization initiator and a diluent. CONSTITUTION:This composition is formed by mixing 100 pts.wt. prepolymer (A) having a carboxyl and an ethylenically unsaturated group in the molecule and an acid value of 30-160mgKOH/g with 0.5-30wt.%, based on the nonvolatile matter of the obtained composition, compound (B) of formula I (wherein R1 is H or CH3; R2 is H, CH3, C2H5, C3H7, C4H9 or formula II), which is a compound which can be copolymerized with component A by ultraviolet radiation and whose -CH2-O-R group can be crosslinked by itself when heated and is crosslinkable with a component A/component B copolymer formed by ultraviolet radiation, 0.2-30 pts.wt. photopolymerization initiator (C), 20-300 pts.wt. diluent (D) comprising a photopolymerizable vinyl monomer and/or an organic solvent, and optionally a filler, a colorant, an antifoamer, etc.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention relates to a novel and useful resist composition, and more particularly to an ethylenically unsaturated group-containing brevolimer having a carboxyl group in its molecule, which is crosslinkable. It contains as essential components a chemical compound, a photopolymerization initiator, and a diluent, and has excellent photocurability, thermosetting properties, heat resistance, adhesion, and chemical resistance, especially for consumer printed wiring boards and industrial use. The present invention relates to a resin composition suitable for a solder resist that can be developed with a weak alkaline aqueous solution and is suitable for manufacturing printed wiring boards, etc., and a cured product thereof.

(Prior Art) In recent years, ultraviolet curable compositions have been widely used for reasons such as resource saving, energy saving, improved workability, and improved productivity. In the field of printed wiring board processing, various inks such as solder resist inks and marking inks have been shifting from conventional thermosetting compositions to ultraviolet curable compositions for the same reason. Among these, solder resist inks were the first to transition to UV-curable compositions.

(Problems to be Solved by the Invention) Screen printing methods have often been used to form resist patterns on printed wiring boards, but when such screen printing methods are used, bleed, smearing, or Phenomena such as sag and sag occur, and as a result, it is no longer possible to cope with the recent increase in the density of printed wiring boards.

To solve these problems, there are dry film type photoresists and liquid developable resist inks, but dry film type photoresists tend to produce air bubbles during thermocompression bonding and have poor heat resistance. There are also problems such as concerns about adhesion and high price. On the other hand, currently commercially available liquid resists use organic solvents as developing solutions, resulting in air pollution problems, expensive solvents, and problems with solvent resistance and acid resistance.

(Means for Solving the Problems) In order to solve the problems described above, the present inventors have conducted extensive research and found that a dilute alkali film with excellent heat resistance, adhesion, chemical resistance, plating resistance, and electrical insulation properties has been developed. Can be developed with an aqueous solution.
We have succeeded in providing a resin composition suitable for solder resist.

That is, the present invention provides: 1) an ethylenically unsaturated group-containing gleborimer (A) having a carboxyl group in the molecule, and general formula CI) (in formula CII, R is 1 or CHs, R2 is H, CH
3. C2H5, C3H7, C4H9 or -CH{
◇Yes. ) A photosensitive thermosetting resin composition containing a photopolymerization initiator (0) and a photopolymerizable vinyl monomer and/or an organic solvent as a diluent, especially a solder resist. The present invention relates to resin compositions and cured products thereof.

Each component of the photosensitive thermosetting resin composition of the present invention will be explained below.

As the ethylenically unsaturated group-containing Brevolimer (A) having a carboxyl group in the molecule, epoxy resins [for example, Nopolac type epoxy resin (manufactured by Toto Kasei@,
YDCN-701, YDCN-704, YDPN-63
8, YDPN-602; manufactured by Dow Chemical Company, DEN-
4 3 L DEN-4 3 9 ; Manufactured by Ciba Geigy, EPN-1138, EPN-1235, EPN-1
299; Inu Nippon Ink Chemical Industry Co., Ltd., N? 30, N-77
0, N-865, N-665, N-673, V N-695, YH-4 1 50, VH-4240, V
H-4440; manufactured by Nippon Kayaku ■, EOCN-1 20,
EOCN-104, BRPN-1020; manufactured by Asahi Kasei Industries, ECN265, ECN-293, ECN-285,
ECN-299, etc.) bisphenol A type, bisphenol F type, hydrogenated pisphenol A type, brominated and spphenol A type, amino group-containing, alicyclic or polyphtadiene modified glycidyl ether type epoxy resins (e.g. Manufactured by Yuka Ciel, Nibikoat 828, Epicor}1
007, Ebicoat 807; manufactured by Dainippon Ink and Chemicals,
Ebikuron 840, Ebikuron 8601 Epicuron 3
0 5 0, Ebicuron 830; manufactured by Dow Care Co., Ltd.
DER-330, DER-337, DER-361;
Manufactured by Daicel Chemical Industries, Ltd., Heptanoxide 2021, Heptanokide 3000; Manufactured by Mitsubishi Gas Chemical, TETRAD-X, T
ETRAD-C; manufactured by Nippon Soda, EPB-13, EPB-127; manufactured by Toto Kasei, YD-1 1 6, YD-1 2
8, YD-013, YD-020, YDG-414
,ST-3000,ST-110,YDF-190,Y
DF-2004, YDF-2007; manufactured by Ciba Geigy, GY-260, GY-255, XB-2615; manufactured by Dow Chemical, DER-332, DER-662,
DER-542, etc.) and tris(hydroxyphenyl)methane paste epoxy resins (e.g., Dow Chemical Co., Ltd., Tactex-742, XD-9053; Nippon Kayaku Co., Ltd., EPPN-502, etc.). It will be done. ]
and (meth)acrylic acid, and then polybasic carboxylic acid or its anhydride (e.g., maleic acid, phthalic acid, tetrahydrophthalic acid, hexahydrophthalic acid,
head acids, anhydrides of these acids, etc.), compounds obtained by reacting the reaction product of the epoxy resin and (meth)acrylic acid with the polybasic carboxylic acid or its anhydride, and diisocyanates. (meth)acrylates having one hydroxyl group in one molecule (e.g., tolylene diisocyanate, xylylene diisocyanate, hydrogenated xylylene diisocyanate, hexamethylene diisocyanate, isophorone diisocyanate, diphenylmethane diisocyanate, etc.); Examples include adducts with hydroxyethyl (meth)acrylate, hydroxyprobyl (meth)acrylate, hydroxybutyl (meth)acrylate, trimethylolpropane di(meth)acrylate, pentae(meth)acrylate, etc.). The preferred range of the acid value of these ethylenically unsaturated group-containing prebolimers is 30 to 16.
0 mgKoH/g, particularly preferably 4 5 to
120 mgKoH/g.

The reaction between epoxy resins and (meth)acrylic acid is based on (meth)acrylic acid per chemical equivalent of the epoxy group of the epoxy resins.
Acrylic acid approx. 0. The reaction is carried out at a ratio of 8 to 1.5 chemical equivalents, particularly preferably about 0.9 to 1.1 to 1 chemical equivalent, and during the reaction, an organic solvent such as butyl cellosolve acetate, carbitol acetate, ethyl methyl ketone, etc. It is preferable to use a catalyst (for example, penzyldimethylamine, triethylamine, penzyltrimethylammonium chloride, penzyltriethylammonium furomite, triphenylstipine, etc.) to further promote the reaction. The amount used is 01 to 10% by weight, particularly preferably 0.3 to 5% by weight, based on the reaction mixture.
Weight%. In order to prevent polymerization during the reaction, it is preferable to use a polymerization inhibitor (for example, methoquinone, hydroquinone, phenothiazine, etc.), and the amount used is 0.01 to 1% by weight based on the reaction mixture, especially Preferably it is 0.05 to 0.5% by weight. The reaction temperature is 60-1
The temperature is 50°C, particularly preferably 80 to 120°C.

The reaction between the reaction product of epoxy resins and (meth)acrylic acid obtained by the above method and polybasic carboxylic acid or its anhydride (esterification reaction of hydroxyl group in epoxy (meth)acrylate) is an epoxy resin. 0.05 to 1.00 chemical equivalents of the acid or its anhydride are reacted per chemical equivalent of hydroxyl groups in the reaction product of resins and (meth)acrylic acid. The reaction temperature is 60-150°C, particularly preferably 80-100°C.

Next, an adduct of the residual hydroxyl group in the esterification reaction product of the hydroxyl group in the epoxy (meth)acrylate and the (meth)acrylate having one hydroxyl group in one molecule via the diisocyanate, First, for example, the diisocyanates and the (meth)acrylates having one hydroxyl group in one molecule are mixed in an equimolar ratio of 30 to 30 by a conventional method.
The reaction is carried out for 2 to 12 hours by heating and stirring at ~100°C to synthesize half-urethane (meth)acrylate.

Next, the obtained half-urethane (meth)acrylate is mixed with 0.00% incyanate of half-urethane (meth)acrylate per chemical equivalent of the remaining hydroxyl group in the esterification reaction product of the hydroxyl group in the epoxy (meth)acrylate. 1 chemical equivalent or more, preferably 0. 3 in a ratio of more than 2 chemical equivalents
It can be obtained by reacting at 0 to 100°C for 2 to 12 hours.

The composition according to the invention uses compounds of the general formula [I]. The compound (B) is copolymerized with the ethylenically unsaturated group-containing prepolymer (A) by irradiation with ultraviolet rays, and when heated, the compound (-CH2-0 in Bl) is copolymerized.
The -R group is advantageously crosslinkable by itself and is crosslinkable with a copolymer formed by ultraviolet irradiation of the ethylenically unsaturated group-containing prepolymer and compound (8). suitable. The compound (Bl is
Usually about 0.0% based on its non-volatile components in the composition. 5～
It is used in an amount of 30% by weight, preferably from 1 to 20% by weight. By heating and curing the carboxyl group of the ethylenically unsaturated group-containing prebolimer (A) having a carpoxyl group in the molecule and compound 03), various properties of the resin composition of the present invention after curing are made excellent. be able to.

Compounds (Specific examples of B include N-methylol acrylamide, N-methylol methacrylamide, N-methoxymethyl acrylamide, N-methoxymethyl methacrylamide, N-ethoxymethyl acrylamide, N-ethoxymethyl methacrylamide, −(n
-butoxymethyl)acrylamide, N-(n-butoxymethyl)methacrylamide, N-(iso-butoxymethyl)acrylamide, N-(iso
-butoxymethyl) methacrylamide, N-penzyloxymethyl acrylamide, N-penzyloxymethyl methacrylamide, and the like. Preferred examples of the compound } include N-methylol acrylamide, N-n-ptoxymethyl acrylamide, and the like.

Next, a photopolymerization initiator (typical examples of Q include penzoin, penzyl, penzoin methyl ether, penzoin isopropyl ether, acetophenone, 2.2-
Dimethoxy-2-phenylacetophenone, 2.2-diethoxy-2-phenylacetophenone, 1.1-dichloroacetophenone, 1-hydroxycyclohexyl phenyl ketone, 2-methyl-l-[4-(methylthio)
phenyl]-2-morphoIJ/-7”ropan-1-one, N,N-dimethylaminoacetophenone,
2-methylanthraquinone, 2ethylanthraquinone, 2-tert-butylanthraquinone, 1-chloroanthraquinone, 2-amylanthraquinone, 2-
Aminoanthraquinone, 2,4-dimethylthioxanthone, 2,4-diethylthioxanthone, 2,4-diisobrobyl 4,4-bisdiethylaminobenzophenone,
Michler's ketone and the like can be mentioned. These can be used alone or in combination of two or more. Furthermore, such a photopolymerization initiator (Q is a known and commonly used photosensitizer such as N,N-dimethylaminobenzoic acid ethyl ester, N,N-dimethylaminobenzoic acid isoamyl ester, triethanolamine, triethylamine) alone. Alternatively, 2a! or more can be used in combination.The preferred range of the usage amount of the photopolymerization initiator (Q) is as follows:
0.2 to 30 parts by weight, preferably 2 parts by weight
~20 parts by weight. Next, as the diluent, a photopolymerizable vinyl monomer and/or an organic solvent can be used. Typical photopolymerizable vinyl monomers include:
2-hydroxyethyl acrylate, 2-hydroxybutyl acrylate, tripropylene diacrylate}, N
, N-dimethylacrylamide, trimethylolpropane triacrylate, pentaerythritol triacrylate, dipentaerythritol penta- and hexaacrylate, tris-hydroxyethyl isocyanurate di- and triacrylate, phenoxy acrylate, ethylene oxide adduct acrylate of bisphenol A, Examples include trimethylolpropane triethoxy triacrylate and trimethylolpropane triglycidyl ether acrylate. On the other hand, examples of organic solvents include ethyl methyl ketone, cyclohexanone, toluene, xylene, methyl selon, butyl cellosolve, methyl carbitol, butyl carpitol, propylene glycol monomethyl ether, dipropylene glycol monoethyl ether, and triethylene glycol monoethyl ether. , ethyl acetate, butyl acetate, propanol, petroleum ether, petroleum naphtha, hydrogenated petroleum naphtha, nrupent naphtha, and the like. The above-mentioned diluent 0 may be used alone or as a mixture of two or more, and the preferred amount used is 20 to 20 parts by weight per 100 parts by weight of the ethylenically unsaturated group-containing prepolymer (A).
The amount is 300 parts by weight, preferably 30 to 200 parts by weight.

Furthermore, if necessary, fillers such as barium sulfate, silicon oxide, Merck, clay, calcium carbonate, coloring pigments such as phthalocyanine blue, phthalocyanine green, titanium oxide, carbon black, antifoaming agents, adhesion imparting agents, or Various additives such as leveling agents, or polymerization inhibitors such as hydroquinone, hydroquinone monomethyl ether, birogallol, tert-butylcatechol, and phenothiazine may also be added.
Eboxy compounds containing two or more epoxy groups in one molecule, such as glycidyl-type epoxy resins or alicyclic epoxy resins, amine compounds, imidazole compounds,
It is also possible to use a small amount of an epoxy curing agent such as a phenolic photocationic polymerization catalyst. Suitable irradiation light sources for curing the composition of the present invention include low pressure, medium pressure, high pressure and extra high pressure mercury lamps, xenon lamps, metal halide lamps and the like. The composition of the present invention is particularly useful as a solder resist resin composition, but can also be used as an insulating material, an impregnating material, a surface coating material, a paint, an adhesive, and the like.

When using the composition of the present invention as a solder resist,
The thickness of the cured product is preferably about 5 to 50 μm.

(Example) Hereinafter, the present invention will be specifically explained with reference to Examples.

[Example of synthesis of ethylenically unsaturated group-containing brevolimer having a carboxyl group in the molecule]

Synthesis example 1. Phenol novolak type epoxy resin (manufactured by Nippon Kayaku@,
EPPN-201: Evoxy equivalent 180) 1800g and acrylic acid 720g, }rifenyl stipine 26g1
After charging 1.25 g of hydroquinone and 1407 g of Butyl Cetol Solv Acetate and reacting at 95°C for 24 hours, 740.6 g of hexahydrophthalic anhydride was charged.
The reaction was carried out at 0°C for 24 hours to obtain a compound having an acid value of 8 6 mgKoH/g (excluding butyl cellosolp acetate).

Synthesis example 2. Cresol nopolac type epoxy resin (manufactured by Nippon Kayaku ■,
EOCN-103: Epoxy equivalent weight 218) 2 1 8
0 g, 720.6 g of acrylic acid, 26 g of liphenyl stibine, 1.25 g of hydroquinone, and 1651 g of butyl cellosolve acetate, and then reacted at 95°C for 24 hours, followed by 925 g of tetrahydrophthalic anhydride.
g was charged and reacted at 90°C for 24 hours. 6
A compound with an acid value (excluding phtyl cellosol acetate) of mgKoH/H was obtained.

Examples 1 to 4, Comparative Example 1. A solder resist resin composition was blended according to the composition shown in Table 1, and applied to a copper through-hole printed wiring board with a film thickness of 20 to 100 μm using a screen printing method. After drying the coating film at 80°C for 60 minutes, , Apply the negative film to the paint film directly or without contacting it. then 5
Ultraviolet rays are irradiated using an Ogi ultra-high pressure mercury lamp, and then 1.
The unirradiated part of the coating film was dissolved and removed using an alkaline aqueous solution such as 5% Na2C (aqueous solution).
Heat curing was performed at 0° C. for 60 minutes, and various performance tests were conducted on each of the obtained specimens. The results are shown in Table 1.

(Developability) Using a 5KW ultra-high pressure mercury lamp, irradiate ultraviolet rays and develop 9X-
The non-irradiated portion was dissolved and removed with a 1.5% Na2CO3 aqueous solution at 30° C., and the quality of the product was evaluated. The judgment criteria are as follows.

○・・・・・・Dissolution rate is fast.

×・・・・・・Does not dissolve or dissolves extremely slowly.

(Solder heat resistance) The state of the coating film after being immersed in molten solder at 260° C. for 2 minutes was evaluated. The judgment criteria are as follows.

○・・・・・・No abnormality in the appearance of the paint film.

×・・・・・・・The coating film swells, melts, and peels off.

(Solvent Resistance) After being immersed in methylene chloride at 20° C. for 1 hour, the state and adhesion of the coating film were comprehensively evaluated. The criteria for judgment are exactly what they say.

○・・・・・・No abnormality in the appearance of the paint film.

×・・・・・・・・・The paint film swells, blisters, and falls off.

(Adhesion) 10 goblets of 1×IIOI size are placed on the coating film of the specimen.
The adhesion after peeling off with cellophane tape in 0-piece increments was evaluated.

(Pencil hardness) The highest hardness that does not cause scratches on the film is indicated using a pencil hardness tester according to the test method of JIS K-5400 when a load of 1 kg is applied.

(Acid resistance) The condition and adhesion of the coating film after immersion in a 10% by weight aqueous hydrochloric acid solution at 20° C. for 30 minutes were comprehensively evaluated. The judgment criteria are as follows.

○・・・・・・・・・The paint film has completely changed to red.

×・・・・・・・・・The paint film swells and falls off.

(Gold Plating Resistance) After gold plating was performed for 15 minutes at a current density of IA/dm using Autoronex CI (plating solution) manufactured by Cellex, a peeling test of the coating film was performed using Sellotape. The judgment criteria are as follows.

○・・・・・・・・・Does not peel off at all.

x: Part or all of the paint film peeled off.

(Insulation Resistance) According to JISZ-3197K, the film was left in an atmosphere of 80° C. and 95% RH for 240 hours, and the insulation resistance of the coating film was measured.

DETX: manufactured by Nippon Kayaku ■, photoinitiator, diethylthioxanthone EPA: manufactured by Nippon Kayaku ■, photosensitizer, N,N-dimethylbenzoic acid ethyl ester KAYARAD DPHA: Made by Nippon Kayaku ■, polyfunctional acrylate, dipentaerythritol benta and hexaacrylate EPPN-2 01: Made by Nippon Kayaku ■, phenol noporac type epoxy resin SP-170: Made by Asahi Denka 7■, photocationic polymerization catalyst (invention) (Effect) The resin composition of the present invention is a solder resist resin composition that can be developed with a dilute alkaline aqueous solution and has excellent heat resistance, adhesion, solvent resistance, acid resistance, plating resistance, moisture resistance, electrical properties, etc. suitable for

Claims (1)

[Claims] 1) Ethylenically unsaturated group-containing prepolymer (A) having a carboxyl group in the molecule and the general formula [I]▲There are mathematical formulas, chemical formulas, tables, etc.▼[I] (in the formula, R_1 is H or CH_3, and R_2 is
H, CH_3, C_2H_5, C_3H_7, C_4H
＿9 or ▲There are mathematical formulas, chemical formulas, tables, etc.▼. ) A photosensitive thermosetting resin composition comprising a compound (B) represented by (B), a photopolymerization initiator (C), and a photopolymerizable vinyl monomer and/or an organic solvent as a diluent (D). 2) Ethylenically unsaturated group-containing prepolymer (A) that has a carboxyl group in the molecule and the general formula [I] ▲ Numerical formula, chemical formula, table, etc. ▼ [I] (In the formula, R_1 is H or CH_3 Yes, R_2 is
H, CH_3, C_2H_5, C_3H_7, C_4H
＿9 or ▲There are mathematical formulas, chemical formulas, tables, etc.▼. ) A solder resist resin composition comprising a compound (B) represented by the formula (B), a photopolymerization initiator (C), and a photopolymerizable vinyl monomer and/or an organic solvent as a diluent (D). 3) A cured product of the resin composition according to item 1 or 2.