JPH0850353A - Photosensitive resin composition and printed circuit board using same - Google Patents

Abstract

PURPOSE:To obtain a photosensitive resin compsn. developable with an aq. soln. causing no problem of safety or environmental problem and excellent in heat resistance, adhesiveness and flame retarding property and to obtain a printed circuit board using the resin compsn. CONSTITUTION:This photosensitive resin compsn. contains epoxy acrylate having a carboxyl group, epoxy resin and at least one kind of acrylate compd. as a halogen substitution product. This compsn. can be developed with a developer almost harmless to the human body and not corresponding to a dangerous article, gives a coating film excellent in resolution, heat resistance, adhesiveness and flame retarding property and can be used as a soldering resist, a plating resist or an interlaminar insulating layer for a multilayered printed circuit board.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to an interlayer insulating material for a printed wiring board, which is excellent in photocurability, thermosetting, heat resistance, adhesiveness and flame retardancy and which can be developed by an aqueous alkaline solution or an organic solvent solution. The present invention relates to a suitable photosensitive resin composition and a printed wiring board using the same.

[0002]

2. Description of the Related Art With the progress of electronic technology, multi-layer printed boards used in various electronic devices are required to have a high density. In recent years, development of multi-layer printed boards in which wiring is connected by via holes has been advanced. Has been. When using a solder resist or plating resist used in conventional printed wiring boards, etc. for the interlayer insulating material, heat resistance, adhesiveness,
There is a problem with flame retardancy. Further, it is common to use an organic solvent such as chlorocene for the developing solution, and use of such an organic solvent is concerned about safety and environmental problems.

On the other hand, a resist ink developable with an alkaline aqueous solution (Japanese Patent Publication No. 1-54390) has been proposed. However, there is a problem in flame retardancy as an interlayer insulating material.

[0004]

The object of the present invention is to develop a photosensitive resin composition which can be developed in an aqueous solution which does not cause any problems in safety and environment, and which is excellent in heat resistance, adhesiveness, especially flame retardancy. And to provide a printed wiring board using the same.

[0005]

Means for Solving the Problems The gist of the present invention for solving the above problems is that at least one of (a) a carboxyl group-containing epoxy acrylate, (b) an epoxy resin, and (c) an acrylate compound is a halogen-substituted compound. A photosensitive resin composition and a printed wiring board using the same.

The photosensitive resin composition of the present invention contains a carboxyl group-containing epoxy acrylate obtained by reacting a product obtained by reacting an epoxy resin with an unsaturated carboxylic acid with a polybasic acid anhydride.

The epoxy resin used in the (a) carboxyl group-containing epoxy acrylate of the present invention is a bisphenol A type epoxy resin, a bisphenol F type epoxy resin, a bisphenol S type epoxy resin, a phenol novolac type epoxy resin, a cresol novolac type epoxy resin. , Cycloaliphatic epoxy resins, glycidyl ester resins, glycidyl amine resins, heterocyclic epoxy resins, brominated bisphenol A type epoxy resins, brominated phenol novolac type epoxy resins, and the like.
In particular, a novolac type epoxy resin having excellent heat resistance and a brominated phenol novolac type epoxy resin having excellent flame retardancy are useful.

The unsaturated carboxylic acid used in the present invention includes acrylic acid, methacrylic acid, crotonic acid, cinnamic acid and the like.

The polybasic acid anhydrides include maleic anhydride, succinic anhydride, itaconic anhydride, phthalic anhydride, tetrahydrophthalic anhydride, tetrabromophthalic anhydride, methyltetrahydrophthalic anhydride and endomethylenetetrahydrophthalic anhydride. Acid, methylendomethylenetetrahydrophthalic anhydride, methylbutenyltetrahydrophthalic anhydride, hexahydrophthalic anhydride, methylhexahydrophthalic anhydride, trimellitic anhydride, pyromellitic anhydride, benzophenonetetracarboxylic acid anhydride, dodecenylsuccinic anhydride , Methylcyclohexene dicarboxylic acid anhydride, chlorendic acid anhydride, polyazelaic acid anhydride and the like. The addition amount of these polybasic acid anhydrides is not particularly limited, but the acid value of the obtained carboxyl group-containing epoxy acrylate is 15 to 100 mg KO.
A range of H / g is preferred.

The reaction between the epoxy resin and the unsaturated carboxylic acid is carried out by dissolving the epoxy resin in an organic solvent such as methyl ethyl ketone, methyl cellosolve acetate, ethyl cellosolve acetate, cyclohexanone or propylene glycol monomethyl ether acetate, and using triethylamine or tri-n as a catalyst. -A tertiary amine such as butylamine and diethylcyclohexylamine, a quaternary ammonium salt such as benzyltrimethylammonium chloride and benzyltriethylammonium chloride, and hydroquinone and p-methoxyphenol as a polymerization inhibitor are used.
Stir and mix at ~ 150 ° C to react. Further, a carboxyl group-containing epoxy acrylate is obtained by adding a polybasic acid anhydride and reacting it in the same manner.

The (b) epoxy resin of the present invention is a bisphenol A type epoxy resin, a bisphenol F type epoxy resin, a bisphenol S type epoxy resin, a phenol novolac type epoxy resin, a cresol novolac type epoxy resin, a cycloaliphatic epoxy resin, Glycidyl ester resin, glycidyl amine resin, heterocyclic epoxy resin, brominated bisphenol A type epoxy resin, brominated phenol novolac type epoxy resin, modified epoxy resin such as silicone or nitrile rubber, fine particle dispersed epoxy resin such as acrylic rubber Etc. The blending amount of these is not particularly limited, but when the amount of the epoxy resin is large, the developability is poor, and when the amount is small, the adhesion, heat resistance and the like are deteriorated, so 30 to 70 parts by weight is a good blending amount. is there.

The (b) acrylate compound of the present invention includes polyethylene glycol diacrylate, trimethylolpropane triacrylate, diethylene glycol diacrylate, butylene glycol diacrylate, hexanediol diacrylate, pentaerythritol triacrylate, triethylene glycol diacrylate, neo. Pentyl glycol diacrylate, dipentaerythritol hexaacrylate, tricyclodecane dimethylol diacrylate, polycarbonate diol diacrylate, phenoxy polyethylene glycol acrylate, bis [4- (acryloxy polyethoxy)
Phenyl] propane, acrylate of bisphenol A, phenoxyethyl acrylate, nonylphenoxyethyl acrylate, tetrahydrofurfuryloxyethyl acrylate, cyclohexaneoxyethyl acrylate, tricyclodecanyloxy acrylate, glycerol acrylate and their methacrylates,
Other epoxy acrylate, urethane acrylate,
Examples thereof include polyester acrylate and the above halides. The compounding amount is not particularly limited, but is 5
-50 parts by weight are good.

As the halogen content of the above resin composition,
5 to 25% by weight is preferable, and bromide is particularly preferable.

The photosensitive resin composition of the present invention contains a photopolymerization initiator and an epoxy resin curing agent in addition to the above. As the photopolymerization initiator, benzophenone, 2,2-dimethoxy-1,2-diphenylethan-1-one, 2,4-diethylthioxanthone, P-dimethylaminobenzoic acid isoamyl ester, 1-hydroxycyclohexylphenyl ketone, 2 -Methyl-1- [4- (methylthio) phenyl] -2-monforinopropanone-1,2-gendyl-2-dimethylamino-1- (4-morpholinophenyl) -butanone-1,2-hydroxy -2-methyl-1
-Phenylpropan-1-one, 2,4,6-trimethylbenzoyldiphenylphosphine oxide, 1- [4
-(2-Hydroxyethoxy) -phenyl] -2-hydroxy-2-methyl-1-propan-1-one, bis (cyclopentadienyl) -bis [2,6-difluoro-3-
(Pyr-1-yl) titanium], bisacylphosphine oxide, (η ⁵ -2,2-cyclopentadiene)
[(1,2,3,4,5,6--η)-(1-methylethyl) benzene] -iron (1 +)-hexafluorophosphate (1-) and the like, and at least one of them is used. be able to. Further, known photopolymerization accelerators such as benzoic acid type and tertiary amine type may be used in combination. The compounding amount of such a photopolymerization initiator is used in the range of 0.2 to 10%.

As the epoxy resin curing agent, amine type curing agents such as diaminodiphenyl sulfone, diaminodiphenylmethane, piperidine and tetramethylguanidine,
Acid anhydrides such as trimellitic anhydride, tetrahydrophthalic anhydride, hexahydrophthalic anhydride, polyazelainic anhydride, 2-heptadecylimidazole, 1-cyanoethyl-2-ethyl-4-methylimidazole, 2,4
-Diamino-6- [2-undecylimidazolyl-
(1)]-Ethyl-S-triazine, 1-dodecyl-2-
Imidazoles such as methyl-3-benzylimidazolium chloride, boron trifluoride amine complex, dicyandiamide and its derivatives, organic acid hydrazide, melamine, aromatic diazonium salts, diallyl iodonium salts,
Triallyl sulfonium salt, triallyl selenium salt,
Phenol resin, amino resin, polyvinyl phenol and the like are used, and one or more of them may be used.

Further, in the photosensitive resin composition of the present invention, talc, silica, titanium oxide, clay, calcium carbonate, magnesium carbonate, ammonium hydroxide, alumina, barium sulfate, antimony trioxide, as a particulate filler,
Aluminum silicate, magnesium silicate, etc. can be blended.
Further, brominated ethylene, brominated imide, brominated polystyrene, brominated diphenyl oxide, brominated aromatic phosphate, antimony oxide, molybdenum compounds and the like may be contained within a range not deteriorating the characteristics, and the surface treatment of the filler. Alternatively, a silane coupling agent can be used. In addition, dyes, pigments, coatability improvers, defoaming agents and the like may be contained.

In the method for producing a printed wiring board using the photosensitive resin composition of the present invention, first, the photosensitive resin composition, a photopolymerization initiator and an epoxy resin curing agent are mixed in a solvent and uniformly dissolved and dispersed. Make a solution. This solution is directly coated on the substrate by a conventional method such as a screen printing method, a dip coating method or a flow coating method, and the solvent is dried to a thickness of 10 to 10.
A photosensitive layer of 0 μm is formed. As the solvent, methyl ethyl ketone, methyl cellosolve, methyl cellosolve acetate, ethyl cellosolve acetate, cyclohexanone, propylene glycol monomethyl ether acetate, diethylene glycol monobutyl ether, diethylene glycol monoethyl ether acetate, or the like is used.

Further, this solution is applied onto a film such as a polyethylene terephthalate film or a polyimide film by a knife coating method or a roll coating method, and dried to obtain a photosensitive material, which is heated on a substrate using a heating roll.
Pressurize to form a photosensitive layer.

The photosensitive layer formed as described above is exposed to a low pressure mercury lamp, a medium high pressure mercury lamp, an ultrahigh pressure mercury lamp, a metal halide lamp, a xenon lamp, a krypton lamp, etc., and developed.

As the developing solution, an alkaline aqueous solution containing sodium carbonate and water and a mixed aqueous solution containing a water-soluble solvent and water are used. As the water-soluble solvent, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol monobutyl ether,
Dipropylene glycol monomethyl ether, methyl lactate, ethyl lactate, butyl lactate, ethyl pyruvate, diethylene glycol, ethanol, γ-butyl lactone,
Methyl cellosolve or the like is used. These organic solvents are used in the range of 10 to 80% with respect to water. Further, it is possible to add an alkali agent such as sodium silicate, sodium hydroxide, sodium borate, monoethanolamine or the like in order to enhance the developability.

The film after development is subjected to a heat treatment at 100 to 200 ° C. and the like to form wiring and an interlayer conductive circuit by electroless plating or the like, whereby a printed wiring board excellent in heat resistance, flame retardancy and the like. Can be obtained.

[0022]

The photosensitive resin composition of the present invention has excellent developability due to the addition of unsaturated carboxylic acid and polybasic acid anhydride, and has excellent heat resistance and adhesiveness due to the epoxy resin. It is considered that the halogen group has excellent flame retardancy.

[0023]

EXAMPLES Next, the present invention will be specifically described based on examples.

Example 1 1 equivalent of bisphenol A type epoxy resin having an epoxy equivalent of 950 and acrylic acid 1.05
Equivalent amount is dissolved in ethyl cellosolve acetate, benzyltrimethylammonium chloride is added as a catalyst, hydroquinone is added as a polymerization inhibitor, and tetrahydrophthalic anhydride is added to the reaction product obtained by reacting at 90 ° C. with respect to 1 equivalent of hydroxyl group. React with 5 equivalents, acid value 63m
An epoxy acrylate of gKOH / g was obtained.

50 parts by weight of the obtained compound, 20 parts by weight of a brominated epoxy resin (BREN-S: made by Nippon Kayaku), 25 parts by weight of an acrylic rubber-dispersed epoxy resin (YR-528: made by Toto Kasei), bis [ 5 parts by weight of 4- (acryloxypolyethoxy) phenyl] propane, photoinitiator 2,2-dimethoxy-1,2-diphenylethane-1-
A photosensitive resin composition containing 5 parts by weight of ON and 3 parts by weight of an epoxy resin curing agent 2-heptadecyl imidazole was obtained.

Example 2 One equivalent of a brominated phenol novolac type epoxy resin having an epoxy equivalent of 280 and 1.05 equivalent of acrylic acid were dissolved in ethyl cellosolve acetate and benzyltrimethylammonium chloride was used as a catalyst.
Hydroquinone was added as a polymerization inhibitor, and the reaction product obtained by reacting at 90 ° C. was reacted with tetrahydrophthalic anhydride in an amount of 0.5 equivalent per 1 equivalent of a hydroxyl group,
An epoxy acrylate having an acid value of 75 mgKOH / g was obtained. 40 parts by weight of the obtained compound and a cresol novolac type epoxy resin (ESCN-220: manufactured by Sumitomo Chemical Co., Ltd.)
30 parts by weight and acrylic rubber-dispersed epoxy resin (YR
-528: manufactured by Toto Kasei Co., Ltd.) 20 parts by weight, bis [4- (methacryloxypolyethoxy) phenyl] propane 10 parts by weight, photopolymerization initiator 1-hydroxycyclohexyl phenyl ketone 3 parts by weight, epoxy resin curing agent 2-hepta A photosensitive resin composition containing 3 parts by weight of decylimidazole was obtained.

Example 3 1 equivalent of a phenol novolac type epoxy resin having an epoxy equivalent of 190 and 0.6 equivalent of methacrylic acid were dissolved in ethyl cellosolve acetate,
Benzyltrimethylammonium chloride as a catalyst and hydroquinone as a polymerization inhibitor are added, and the reaction product obtained by reacting at 90 ° C. is reacted with tetrahydrophthalic anhydride in an amount of 0.5 equivalent per 1 equivalent of a hydroxyl group to give an acid value of 42 mgKOH. / G of epoxy acrylate was obtained. 40 parts by weight of the obtained compound and a brominated epoxy resin (E
BR-700: Manac) 30 parts by weight and acrylic rubber dispersed epoxy resin (YR-528: Toto Kasei) 2
0 parts by weight, 10 parts by weight of bis [4- (methacryloxypolyethoxy) phenyl] propane, a photopolymerization initiator 2,2-
5 parts by weight of dimethoxy-1,2-diphenylethan-1-one, epoxy resin curing agent 2,4-diamino-6- [2
-Undecylimidazoline- (1)] ethyl-S-tothiazine 3 parts by weight of a photosensitive resin composition was obtained.

Example 4 One equivalent of a phenol novolac type epoxy resin having an epoxy equivalent of 190 and acrylic acid of 0.1.
5 equivalents were dissolved in ethyl cellosolve acetate, benzyltrimethylammonium chloride as a catalyst and hydroquinone as a polymerization inhibitor were added, and tetrahydrophthalic anhydride was added to a reaction product obtained by reacting at 90 ° C. with respect to 1 equivalent of a hydroxyl group. After reacting 0.5 equivalent, an acid value of 44
Epoxy acrylate of mg KOH / g was obtained. 50 parts by weight of the obtained compound, 10 parts by weight of a cresol novolac type epoxy resin (ESCN-220: manufactured by Sumitomo Chemical Co., Ltd.) and an acrylic rubber-dispersed epoxy resin (YR-528:
20 parts by weight, brominated bisphenol A methacrylate 20 parts by weight, photopolymerization initiator 2,2-dimethoxy-1,2-diphenylethan-1-one 5 parts by weight,
An epoxy resin curing agent 2-phenyl-4,5-dihydroxymethyl imidazole 3 parts by weight of a photosensitive resin composition was added.

Example 5 One equivalent of a phenol novolac type epoxy resin having an epoxy equivalent of 190 and acrylic acid of 0.1.
5 equivalents were dissolved in ethyl cellosolve acetate, benzyltrimethylammonium chloride as a catalyst and hydroquinone as a polymerization inhibitor were added, and tetrahydrophthalic anhydride was added to a reaction product obtained by reacting at 90 ° C. with respect to 1 equivalent of a hydroxyl group. After reacting 0.5 equivalent, an acid value of 44
Epoxy acrylate of mg KOH / g was obtained. 40 parts by weight of the obtained compound and a brominated epoxy resin (BRE
NS: Nippon Kayaku) 10 parts by weight and acrylic rubber-dispersed epoxy resin (YR-528: Toto Kasei) 20 parts by weight, brominated bisphenol A methacrylate 30 parts by weight, photopolymerization initiator 2-hydroxy-2. A photosensitive resin composition containing 3 parts by weight of methyl-1-phenylpropan-1-one and 3 parts by weight of an epoxy resin curing agent 2-heptadecylimidazole was obtained.

Example 6 40 parts by weight of the epoxy acrylate obtained in Example 1 and brominated epoxy resin (BRE)
N-S) 15 parts by weight and epoxy resin (DT-820
8: Daito Sangyo) 30 parts by weight, diallyl chlorendate (TRIAM605: Wako Pure Chemical Industries, Ltd.) 15 parts by weight, photopolymerization initiator 2,2-dimethoxy-1,2-diphenylethane-
5 parts by weight of 1-one and 3 parts by weight of an epoxy resin curing agent 2-heptadecyl imidazole were mixed to obtain a photosensitive resin composition.

[Comparative Example 1] 1 equivalent of bisphenol A type epoxy resin having an epoxy equivalent of 500 and acrylic acid 1.05
Equivalent amount was dissolved in propylene glycol monomethyl ether acetate, benzyltrimethylammonium chloride as a catalyst and p-methoxyphenol as a polymerization inhibitor were added, and reacted at 90 ° C. to obtain an epoxy acrylate. 50 parts by weight of the obtained compound, 30 parts by weight of polyethylene glycol diacrylate, 20 parts by weight of acrylate-modified NBR (N650: manufactured by Nippon Synthetic Rubber Co., Ltd.), photopolymerization initiator 2,2-dimethoxy-1,2-diphenylethane- A photosensitive resin composition containing 5 parts by weight of 1-one and 3 parts by weight of an epoxy resin curing agent 2-heptadecyl imidazole was obtained.

[Comparative Example 2] 1 equivalent of a cresol novolac type epoxy resin having an epoxy equivalent of 215 and acrylic acid of 0.
Six equivalents were dissolved in propylene glycol monomethyl ether acetate, benzyltrimethylammonium chloride as a catalyst and p-methoxyphenol as a polymerization inhibitor were added, and reacted at 90 ° C. to obtain an epoxy acrylate. 50 parts by weight of the obtained compound, 30 parts by weight of a bisphenol A type epoxy resin (DER661: manufactured by Dow), 20 parts by weight of an acrylate-modified NBR (N650: manufactured by Nippon Synthetic Rubber Co., Ltd.), and a photopolymerization initiator 2,2-dimethoxy. A photosensitive resin composition containing 5 parts by weight of 1,2-diphenylethane-1-one and 3 parts by weight of an epoxy resin curing agent 2-heptadecylimidazole was obtained.

[Comparative Example 3] 1 equivalent of a phenol novolac type epoxy resin having an epoxy equivalent of 190 and acrylic acid 1.
(05 equivalents) were dissolved in ethyl cellosolve acetate, benzyltrimethylammonium chloride as a catalyst and hydroquinone as a polymerization inhibitor were added, and tetrahydrophthalic anhydride was added to the reaction product obtained by reacting at 90 ° C. with respect to 1 equivalent of hydroxyl groups. After reacting 0.5 equivalent, acid value 7
2 mg KOH / g of epoxy acrylate was obtained. 40 parts by weight of the obtained compound, 30 parts by weight of a cresol novolac type epoxy resin (ESCN-220: manufactured by Sumitomo Chemical Co., Ltd.) and an acrylic rubber-dispersed epoxy resin (YR-52).
8: Toto Kasei) 20 parts by weight, bis [4- (methacryloxypolyethoxy) phenyl] propane 10 parts by weight,
A photosensitive resin composition containing 5 parts by weight of a photopolymerization initiator 2,2-dimethoxy-1,2-diphenylethane-1-one and 3 parts by weight of an epoxy resin curing agent 2-heptadecylimidazole was obtained.

15 parts by weight of calcium carbonate was blended with these photosensitive resin compositions, the viscosity was adjusted with a solvent, and the mixture was dispersed by a roll mill to prepare a solution.

This solution was applied onto a copper-clad laminate and dried at room temperature for 20 minutes and at 70 ° C. for 20 minutes to form a photosensitive layer having a thickness of 40 μm. Then, after passing through a negative mask to form a via hole at a predetermined position and exposing at 600 mJ / cm ² using an ultra-high pressure mercury lamp, diethylene glycol monomethyl ether 30% solution at 30 ° C., 120
Spray developed for seconds. Then, after heating at 130 ° C., the surface was roughened with a permanganate solution, and a surface conductor was formed by electroless copper plating.

Table 1 shows the characteristics of the photosensitive resin compositions obtained in the above Examples and Comparative Examples.

Regarding the resolution, the minimum diameter after exposure and development was observed through a mask having a pore size of 30 to 250 μm. The adhesiveness was measured by measuring the adhesive strength after post-curing at 150 ° C. after forming the copper plating.
Regarding the soldering heat resistance, the presence or absence of swelling or peeling was observed with a float at 260 ° C. for 1 minute, and those having no abnormalities are indicated by ◯, and those having swelling or the like are indicated by X. Flame retardance is a result of measurement according to UL standard, and combustion time is within 10 seconds at maximum, V within 5 seconds on average
-0, maximum 30 seconds or less, average 25 seconds or less were evaluated as V-1, and those that burned out were evaluated as HB.

[0038]

[Table 1]

[0039]

According to the present invention, there is little harm to the human body,
It can be developed with a developer that does not correspond to a dangerous substance, and a coating film with excellent resolution, heat resistance, adhesiveness and flame retardancy can be formed. Therefore, it can be used as a solder resist, plating resist, and interlayer insulating layer of multilayer printed wiring boards. Can be used.

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Internal reference number FI Technical display location H05K 3/06 H 3/18 D 7511-4E 3/28 D 3/46 T 6921-4E (72 ) Inventor Yoshinori Kawai 7-1-1 Omika-cho, Hitachi-shi, Ibaraki Hitachi Co., Ltd. Hitachi Research Laboratory (72) Inventor Masanori Nemoto 7-1-1 Omika-cho, Hitachi-shi, Ibaraki Hitachi Hitachi Co., Ltd. (72) Inventor Haruo Akahoshi 7-1-1 Omika-cho, Hitachi-shi, Ibaraki Hitachi Ltd. Hitachi Research Laboratory, Hitachi Ltd.

Claims (7)

[Claims] 1. A photosensitive resin composition, wherein at least one of (a) a carboxyl group-containing epoxy acrylate, (b) an epoxy resin, and (c) an acrylate compound is a halogen-substituted compound. 2. The photosensitive resin composition according to claim 1, wherein the carboxyl group-containing epoxy acrylate has an epoxy residue. 3. The photosensitive resin composition according to claim 1, which has a halogen content of 5 to 25% by weight. 4. The halogen according to claim 1, wherein the halogen is Br.
Alternatively, the photosensitive resin composition as described in 3 above. 5. A print in which the insulating layer is a cured product of a photosensitive resin composition in which at least one of (a) a carboxyl group-containing epoxy acrylate, (b) an epoxy resin, and (c) an acrylate compound is a halogen substitution product. Wiring board. 6. The printed wiring board according to claim 5, wherein the halogen content is 5 to 25% by weight. 7. The printed wiring board according to claim 5, wherein the halogen is Br.