JP2006047501A - Photosensitive resin composition, photosensitive film for permanent resist, method for forming resist pattern, and printed wiring board - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a photosensitive resin composition from which a cured product having sufficiently excellent mechanical characteristics, in particular, sufficiently high tensile strength compared with a conventional material can be formed. <P>SOLUTION: The photosensitive resin composition contains: a cyclic curing agent as a component (A) which opens a ring by heating and can crosslink by itself; a block curing agent as a component (B) which has a group derived from a blocking agent in the molecule and is dissociable in a group derived from the blocking agent by heating; a photopolymerizable compound as a component (C) having an ethylenically unsaturated bond; and a photopolymerization initiator as a component (D). <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a photosensitive resin composition, a photosensitive film for permanent resist, a method for forming a resist pattern, and a printed wiring board.

  A photosensitive resin (photosensitive material) for forming dry film resists and solder resists for circuit formation, and photosensitive resin coating layers used in photovia methods, as electric and electronic parts become smaller, lighter, and more functional. ) Requires high resolution so as to cope with high density on the printed wiring board. These photosensitive resins are produced by exposing a photosensitive resin composition as a raw material to development and image formation. Although the photosensitive resin composition is photocured by exposure, those containing only the photosensitive resin component (photocurable resin component) as a curing component are subjected to adhesion with a substrate and other members and a thermal history. It is difficult to satisfactorily satisfy all the crack resistance and electric corrosion resistance.

  Therefore, a photosensitive resin composition containing a thermosetting resin in addition to the above-described photocurable resin as a curing component has been developed and put into practical use with the intention of satisfying the above characteristics. As the thermosetting component (resin) contained in the photosensitive resin composition, epoxy resin, oxetane resin, phenol resin, melamine resin, benzoxazine and the like are used.

  As an example of such a photosensitive resin composition, Patent Document 1 has excellent heat resistance and adhesion to a wiring layer, and development with excellent resolution is possible even using an aqueous developer that does not use an organic solvent. In order to provide a photosensitive resin composition, a compound (A) having at least one phenolic hydroxyl group and at least one acryloyl group or methacryloyl group in one molecule, an unsaturated imide compound (B), A photosensitive resin composition comprising a photopolymerization initiator (C) and an epoxy compound (D) having at least two epoxy groups in one molecule as constituents has been proposed.

On the other hand, along with further downsizing and higher performance of electronic components in recent years, miniaturization of electronic circuits and thinning of insulating layers are further progressing. The requirements for various properties are becoming more severe, and for example, development of materials with further improved mechanical properties is desired.
JP 2001-342230 A

  However, the present inventors cannot provide a material that sufficiently satisfies the mechanical properties of the level required in recent years with the conventional photosensitive resin compositions including those described in Patent Document 1. I found.

  Therefore, the present invention has been made in view of the above circumstances, and is a photosensitive resin composition capable of forming a cured product having sufficiently superior mechanical properties, in particular, a sufficiently high tensile strength, compared to conventional ones. The purpose is to provide. Moreover, it aims at providing the photosensitive film for permanent resists using such a photosensitive resin composition, the formation method of a resist pattern, and a printed wiring board.

  The photosensitive resin composition of the present invention that achieves the above object comprises: (A) component: a cyclic curing agent that can be ring-opened by heating and crosslink itself; (B) component; a group derived from a blocking agent in the molecule. A block curing agent that can be dissociated by heating and the group derived from the blocking agent, (C) component; a photopolymerizable compound having an ethylenically unsaturated bond, and (D) component; containing a photopolymerization initiator. It is characterized by.

  A cured product (cured film in the case of a film) formed using such a photosensitive resin composition has sufficient tensile strength as compared with a conventional one. The factor is not clarified in detail at present, but the present inventors consider one of the factors as follows. That is, when the photosensitive resin composition of the present invention is heated to cure the component (A), the group derived from the blocking agent in the component (B) molecule is dissociated, and the active group is present in the molecule of the component (B). Generate. The present inventors presume that this active group exerts some action on the active species generated by ring opening of the component (A). However, the factor is not limited to this. Further, the cured product obtained from the photosensitive resin composition of the present invention tends to exhibit a sufficiently good elongation and a sufficiently high glass transition temperature (Tg) in addition to the tensile strength described above from the viewpoint of mechanical properties. It is in. The present inventors consider that the improvement of these mechanical characteristics is caused by the combined use of the component (A) and the component (B).

  Moreover, the hardened | cured material obtained by the photosensitive resin composition of this invention containing each above-mentioned component comes to have the outstanding thermal shock resistance. That is, even if the cured product undergoes a thermal history such as repeated temperature increase and decrease, cracks are less likely to occur. Furthermore, when the thermoset is bonded to a substrate or the like and formed into a layer, the thermal history can sufficiently suppress the peeling of the thermoset from the substrate. The photosensitive resin composition of the present invention can further form a cured film excellent in PCT resistance, electric corrosion resistance, Ni / Au plating resistance, and solder heat resistance. Still further, the photosensitive resin composition of the present invention is excellent in storage stability, and can form a cured film having a desired pattern even after being left for a while after production.

  In the photosensitive resin composition of the present invention, the component (A) is preferably a bismaleimide compound, and the component (B) is preferably a blocked isocyanate compound. Thereby, the mechanical characteristic of the hardened | cured material obtained can be improved further. Furthermore, it is preferable that the component (C) has two or more (meth) acryloyloxy groups per molecule from the viewpoint of easy photocuring.

  The photosensitive resin composition of the present invention preferably contains (E) component; a polymer having a carboxyl group, the (E) component has an ethylenically unsaturated bond, and has a weight average molecular weight of 3000 to 100,000. And more preferred. By using such a polymer, it becomes possible to obtain a photosensitive film for a permanent resist that is less prone to cracking during film formation and that is further excellent in resolution.

  Moreover, the photosensitive resin composition of this invention contains solid content, and it is preferable from the viewpoint of obtaining favorable alkali developability that the acid value of the solid content is 10-150 mgKOH / g.

  In the photosensitive resin composition of the present invention, the component (B) is 10 to 50 parts by mass, the component (C) is 10 to 100 parts by mass, and the component (D) is 0 with respect to 20 parts by mass of the component (A). When contained in an amount of from 1 to 20 parts by mass, various properties including those described above can be made well-balanced, which is preferable.

  The photosensitive film for permanent resists of this invention is equipped with a support body and the photosensitive resin composition layer containing the above-mentioned photosensitive resin composition formed on this support body, It is characterized by the above-mentioned. The photosensitive film for permanent resist may further include a peelable cover film on the photosensitive resin composition layer for permanent resist.

  The method for forming a resist pattern according to the present invention includes the photosensitive resin composition described above so as to cover a conductive layer on an insulating substrate of a multilayer substrate including an insulating substrate and a conductive layer having a circuit pattern formed on the insulating substrate. A photosensitive resin composition layer is formed, and an exposed portion is formed by irradiating a predetermined portion of the photosensitive resin composition layer with an actinic ray, and then a portion other than the exposed portion of the photosensitive resin composition layer. It is characterized by removing.

  A printed wiring board according to the present invention includes an insulating substrate, a conductor layer having a circuit pattern formed on the insulating substrate, and a permanent resist layer formed on the insulating substrate so as to cover the conductor layer. And a permanent resist layer consists of a hardened | cured material of the above-mentioned photosensitive resin composition, and a permanent resist layer has an opening part so that a part of conductor layer may be exposed.

  ADVANTAGE OF THE INVENTION According to this invention, the photosensitive resin composition which can form the hardened | cured material which has the mechanical characteristics sufficiently superior compared with the conventional one, especially a sufficiently high tensile strength can be provided. Moreover, the photosensitive film for permanent resists using such a photosensitive resin composition, the formation method of a resist pattern, and a printed wiring board can be provided.

  Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the drawings as necessary. In the drawings, the same elements are denoted by the same reference numerals, and redundant description is omitted. Further, the positional relationship such as up, down, left and right is based on the positional relationship shown in the drawings unless otherwise specified. Further, the dimensional ratios in the drawings are not limited to the illustrated ratios. In the present specification, “(meth) acrylic acid” means “acrylic acid” and “methacrylic acid” corresponding thereto, and “(meth) acrylate” means “acrylate” and “methacrylate” corresponding thereto. As used herein, “(meth) acryloyl group” means “acryloyl group” and the corresponding “methacryloyl group”.

  The photosensitive resin composition of the present embodiment has a component (A): a cyclic curing agent that can be ring-opened by heating and can itself be crosslinked, and component (B); a group derived from a blocking agent in the molecule, A compound capable of dissociating a group derived from a blocking agent, component (C); a photopolymerizable compound having an ethylenically unsaturated bond, and component (D); a photopolymerization initiator. Hereinafter, each component will be described.

  The cyclic curing agent that is a component (A) that can be ring-opened by heating and can be crosslinked by itself has a cyclic skeleton in the molecule, and when heated, the cyclic skeleton is opened and the polymer network is opened. It means a curing agent to be formed, and a bismaleimide compound is preferred.

The bismaleimide compound is preferably a compound represented by the following general formula (1). In formula (1), R ¹ represents an alkylene group, an arylene group, or a divalent group including an alkylene group and an arylene group. The alkylene group is preferably an alkylene group having 1 to 10 carbon atoms, and more preferably an alkylene group having 1 to 6 carbon atoms. As the arylene group, an arylene group having 6 to 20 carbon atoms is preferable, and an arylene group having 6 to 16 carbon atoms is more preferable. Moreover, as a bivalent group containing an alkylene group and an arylene group, what is shown by following General formula (2) or (3) is preferable.

In formulas (2) and (3), R ³ , R ⁴ , R ⁷ and R ⁸ each independently represent an alkyl group, and R ⁵ , R ⁶ , R ⁹ , R ¹⁰ , R ¹¹ and R ¹² are each independently Represents an alkyl group or a halogen atom. N, m, o, p, q and r each represent an integer of 1 to 4. R ⁵ , R ⁶ , R ⁹ , R ¹⁰ , R ¹¹ and R ¹² may be the same or different.

When R ³ , R ⁴ , R ⁷ and R ⁸ are alkyl groups, the alkyl group is preferably an alkyl group having 1 to 10 carbon atoms, more preferably an alkyl group having 1 to 5 carbon atoms, and R ⁵ , R ^{When 6} , R ⁹ , R ¹⁰ , R ¹¹ and R ¹² are alkyl groups, the alkyl group is preferably an alkyl group having 1 to 10 carbon atoms, more preferably an alkyl group having 1 to 5 carbon atoms.

  Examples of the bismaleimide compound include 1-methyl-2,4-bismaleimide benzene, N, N′-m-phenylene bismaleimide, N, N′-p-phenylene bismaleimide, and N, N′-m-toluylene. Bismaleimide, N, N′-4,4′-biphenylenebismaleimide, N, N′-4,4 ′-[3,3′-dimethylbiphenylene] bismaleimide, N, N′-4,4 ′-[ 3,3′-dimethyldiphenylmethane] bismaleimide, N, N′-4,4 ′-[3,3′-diethyldiphenylmethane] bismaleimide, N, N′-4,4′-diphenylmethane bismaleimide, N, N '-4,4'-diphenylpropane bismaleimide, N, N'-4,4'-diphenyl ether bismaleimide, N, N'-3,3'-diphenylsulfone bis Reimide, N, N′-4,4′-diphenylsulfone bismaleimide, 2,2-bis [4- (4-maleimidophenoxy) phenyl] propane, 2,2-bis [3-tert-butyl-4- ( 4-maleimidophenoxy) phenyl] propane, 2,2-bis [3-s-butyl-4- (4-maleimidophenoxy) phenyl] propane, 1,1-bis [4- (4-maleimidophenoxy) phenyl] decane 1,1-bis [2-methyl-4- (4-maleimidophenoxy) -5-t-butylphenyl] -2-methylpropane, 4,4′-cyclohexylidene-bis [1- (4-maleimide) Phenoxy) -2- (1,1-dimethylethyl) benzene], 4,4′-methylene-bis [1- (4-maleimidophenoxy) -2,6-bis (1,1-dimethyl) Ethyl) benzene], 4,4'-methylene-bis [1- (4-maleimidophenoxy) -2,6-di-s-butylbenzene], 4,4'-cyclohexylidene-bis [1- (4 -Maleimidophenoxy) -2-cyclohexylbenzene, 4,4'-methylene-bis [1- (maleimidophenoxy) -2-nonylbenzene], 4,4 '-(1-methylethylidene) -bis [1- (maleimide) Phenoxy) -2,6-bis (1,1-dimethylethyl) benzene], 4,4 '-(2-ethylhexylidene) -bis [1- (maleimidophenoxy) -benzene], 4,4'- (1-Methylheptylidene) -bis [1- (maleimidophenoxy) -benzene], 4,4′-cyclohexylidene-bis [1- (maleimidophenoxy) -3-methylbenze 2,2-bis [4- (4-maleimidophenoxy) phenyl] propane, 2,2-bis [4- (4-maleimidophenoxy) phenyl] hexafluoropropane, 2,2-bis [3-methyl -4- (4-maleimidophenoxy) phenyl] propane, 2,2-bis [3-methyl-4- (4-maleimidophenoxy) phenyl] hexafluoropropane, 2,2-bis [3,5-dimethyl-4 -(4-maleimidophenoxy) phenyl] propane, 2,2-bis [3,5-dimethyl-4- (4-maleimidophenoxy) phenyl] hexafluoropropane, 2,2-bis [3-ethyl-4- ( 4-maleimidophenoxy) phenyl] propane, 2,2-bis [3-ethyl-4- (4-maleimidophenoxy) phenyl] hexafluoropropyl Pan, bis [3-methyl-4- (4-maleimidophenoxy) phenyl] methane, bis [3,5-dimethyl-4- (4-maleimidophenoxy) phenyl] methane, bis [3-ethyl-4- (4 -Maleimidophenoxy) phenyl] methane, 3,8-bis [4- (4-maleimidophenoxy) phenyl] -tricyclo- [5.2.1.02,6] decane, 4,8-bis [4- (4 -Maleimidophenoxy) phenyl] -tricyclo- [5.2.1.02,6] decane, 3,9-bis [4- (4-maleimidophenoxy) phenyl] -tricyclo- [5.2.1.02, 6] Decane, 4,9-bis [4- (4-maleimidophenoxy) phenyl] -tricyclo- [5.2.1.02,6] decane, 1,8-bis [4- (4-maleimidopheno) Cis) phenyl] menthane, 1,8-bis [3-methyl-4- (4-maleimidophenoxy) phenyl] menthane, 1,8-bis [3,5-dimethyl-4- (4-maleimidophenoxy) phenyl] Mentin etc. can be mentioned. These can be used alone or in combination of two or more.

  The block curing agent (occlusion curing agent) that is a component (B) and has a group derived from the blocking agent in the molecule, and the group derived from the blocking agent can be dissociated by heating, is generated by the reaction of a predetermined compound and the blocking agent. The compound is temporarily inactivated by a group derived from a blocking agent, and when heated at a predetermined temperature, the group derived from the blocking agent is dissociated to generate an active group. As the component (B), a blocked isocyanate compound is preferable. The blocked isocyanate compound generates an isocyanate group when heated. Although it does not specifically limit as a predetermined compound which can react with a blocking agent, For example, an isocyanate compound is mentioned. Examples of the isocyanate compound include isocyanurate type, biuret type, and adduct type. Among these, it is preferable to use the isocyanurate type because the adhesiveness of the photosensitive resin composition to the substrate or the like tends to be further improved. .

  Specific examples of isocyanate compounds that can react with the blocking agent include 4,4′-diphenylmethane diisocyanate, 2,4-tolylene diisocyanate, 2,6-tolylene diisocyanate, naphthalene-1,5-diisocyanate, and o-xylylene diene. Aromatic polyisocyanates such as isocyanate, m-xylylene diisocyanate, 2,4-tolylene dimer, aliphatic polyisocyanates such as hexamethylene diisocyanate, 4,4-methylenebis (cyclohexyl isocyanate), isophorone diisocyanate, bicycloheptane triisocyanate, etc. Of alicyclic polyisocyanate. Among these, aromatic polyisocyanates are preferable from the viewpoint of heat resistance, and aliphatic polyisocyanates or alicyclic polyisocyanates are preferable from the viewpoint of preventing coloring.

  As a blocking agent, what has active hydrogen is preferable, and an active methylene compound, a diketone compound, an oxime compound, a phenol compound, an alkanol compound, a caprolactam compound, etc. are mentioned. Specifically, methyl ethyl ketone oxime, ε-caprolactam and the like can be used.

  The block isocyanate compound may be commercially available, for example, Sumidur BL-3175, BL-4165, BL-1100, BL-1265, BL-3272, Death Module TPLS-2957, TPLS- 2062, TPLS-2957, TPLS-2078, TPLS-2117, DESLS-2117, Desmotherm 2170, Desmotherm 2265 (above, trade name, manufactured by Sumitomo Bayer Urethane Co., Ltd.), Coronate 2512, Coronate 2513, Coronate 2520 (above, Nippon Polyurethane Industry Co., Ltd.) Product name). Sumijoules BL-3175 and BL-4265 are obtained using methylethyloxime as a blocking agent, and Sumijoule BL-3272 is obtained using ε-caprolactam as a blocking agent.

  The dissociation temperature of the group derived from the blocking agent in the blocked isocyanate compound is 120 to 200 ° C. from the viewpoint of the influence on the constituent material of the electronic component using the photosensitive resin composition, the manufacturing environment, the process conditions, the material storage temperature, and the like. preferable.

  The photopolymerizable compound having an ethylenically unsaturated bond as component (C) can improve the photosensitivity and crosslinking density characteristics of the photosensitive resin composition, and toughen the resulting cured product. Is possible. Such photopolymerizable compounds include (meth) acrylic acid, (meth) acrylic acid esters having a hydroxyl group such as 2-hydroxylethyl (meth) acrylate, hydroxylpropyl (meth) acrylate, methyl (meth) acrylate, (Meth) acrylic acid and (meth) acrylic acid composed of (meth) acrylic acid ester and (meth) acrylic acid composed of aliphatic alcohol such as butyl (meth) acrylate and (meth) acrylic acid (Meth) acrylic acid ester having an epoxy group such as acrylic acid ester, glycidyl (meth) acrylate, ethylene glycol di (meth) acrylate, polyethylene glycol (meth) acrylate, polypropylene glycol (meth) acrylate, trimethylolpropane tri (meth) (Meth) acrylic acid esters of polyhydric alcohols such as acrylate, pentaerythritol tri (meth) acrylate, dipentaerythritol hexa (meth) acrylate, ethoxylated trimethylolpropane tri (meth) acrylate, tetrahydrofurfuryl (meth) acrylate (Meth) acrylic acid ester having a structure containing cyclic ether such as diglycidyl etherified product of bisphenol compound such as bisphenol A and bisphenol F, or (meth) acrylic acid ester added with (meth) acrylic acid to polyethylene glycol or polypropylene glycol , (Meth) acrylic modified novolak type epoxy resin in which (meth) acrylic acid is added to novolak type epoxy resin, N, N-dimethyl (meth) acrylamide, N-methyl (Meth) acrylamides such as (meth) acrylamide, (meth) acrylic acid ester having urethane group, (meth) acrylic acid ester of tris (2-hydroxyethyl) isocyanuric acid, triglycidyl isocyanurate (Meth) acrylic acid ester of glycidyl ether, diallyl phthalate and the like. These can be used individually by 1 type or in combination of 2 or more types.

  In addition, when a urethane compound having an ethylenically unsaturated bond and further having a diol group, a (meth) acryl group or a polyisocyanate group is used as the component (C), the cured product of the photosensitive resin composition is more excellent. It is preferable from the viewpoint of imparting flexibility. Examples of such compounds include AH-600, AT-600, and VA-306H (above, trade name, manufactured by Kyoei Chemical Co., Ltd.).

  Alternatively, it is preferable to use a photopolymerizable compound having two or more (meth) acryloyloxy groups per molecule as the component (C) from the viewpoint of easier photocuring. Examples of such compounds include DPHA (dipentaerythritol hexaacrylate), DPCA-20, DPCA-60 (above, Nippon Kayaku Co., Ltd., trade name), BPE series, G series (above, Shin-Nakamura Chemical Co., Ltd.). Etc.).

  The photopolymerization initiator that is component (D) is not particularly limited, but is preferably matched to the light wavelength of the exposure machine to be used, and known ones can be used. For example, radical photopolymerization initiators include benzophenone, 4,4′-bis (dimethylamino) benzophenone, 4,4′-bis (diethylamino) benzophenone, 4-methoxy-4′-dimethylaminobenzophenone, 2-benzyl- 2-dimethylamino-1- (4-morpholinophenyl) -butanone-1,2-methyl-1- [4- (methylthio) phenyl] -2-morpholinopropan-1-one, 2,2-dimethoxy- Aromatic ketones such as 1,2-diphenylethane-1-one, 2-ethylanthraquinone and phenanthrenequinone, benzoin ethers such as benzoin methyl ether, benzoin ethyl ether and benzoin phenyl ether, benzoins such as methyl benzoin and ethyl benzoin, benzyl Such as dimethyl ketal Derivatives, 2- (o-chlorophenyl) -4,5-diphenylimidazole dimer, 2- (o-chlorophenyl) -4,5-di (m-methoxyphenyl) imidazole dimer, 2- (o- Fluorophenyl) -4,5-diphenylimidazole dimer, 2- (o-methoxyphenyl) -4,5-diphenylimidazole dimer, 2,4-di (p-methoxyphenyl) -5-phenylimidazole dimer 2,4,5-triarylimidazole dimer such as 2- (2,4-dimethoxyphenyl) -4,5-diphenylimidazole dimer, 9-phenylacridine, 1,7-bis (9 , 9'-acridinyl) heptane and the like.

  As the photopolymerization initiator, a photopolymerization initiator that generates a Lewis acid by light irradiation can also be used. Such photopolymerization initiators are generally known, and examples of cationic photoinitiators include triphenyl sulfone hexafluoroantimonate, triphenyl sulfone hexafluorophosphate, and p-methoxybenzenediazonium hexafluorophosphate. Pate, p-chlorobenzenediazonium hexafluorophosphate, diphenyliodonium hexafluorophosphate, 4,4-di-t-butylphenyliodonium hexafluorophosphate, (1-6-n-cumene) (n-dichloropentadiniel ) Iron hexafluorophosphoric acid and the like.

  The blending ratio of each component in the photosensitive resin composition of the present embodiment is such that the component (A) is 20 parts by mass, the component (B) is 10 to 50 parts by mass, and the component (C) is 10 to 100 parts by mass. Parts and the component (D) are preferably 0.1 to 20 parts by mass. When the blending ratio of the component (B) is less than 10 parts by mass, the cured product tends to be brittle, and the adhesion between the layer obtained from the photosensitive resin composition and the substrate on which the layer is formed decreases. Tend to. When the blending ratio of the component (B) exceeds 50 parts by mass, the blending ratio of the component (A) becomes relatively low, so that the Tg of the resin obtained by curing the photosensitive resin composition is low, and a sufficient cured film There is a tendency that characteristics cannot be obtained, and electric corrosion resistance tends to be lowered.

  When the blending ratio of the component (C) is less than 10 parts by mass, or when the blending ratio of the component (D) is less than 0.1 parts by mass, photocuring is insufficient, so a resist pattern is formed from the photosensitive resin composition. In this case, the sensitivity and resolution tend to decrease. When the blending ratio of component (C) exceeds 100 parts by mass, or when the blending ratio of component (D) exceeds 20 parts by mass, the heat resistance of the resulting cured product tends to decrease.

  In the photosensitive resin composition of the present embodiment, it is preferable that a polymer having a carboxyl group is further contained as the component (E) from the viewpoint of imparting good alkali developability to the cured product. The component (E) may be a photosensitive polymer (photosensitive prepolymer) or a non-photosensitive polymer. As the photosensitive polymer having a carboxyl group, a compound obtained by addition reaction of a saturated or unsaturated polybasic acid anhydride to an ester compound obtained by reacting an epoxy compound with an unsaturated carboxylic acid is preferably used. It is done.

  As an epoxy compound used as the raw material of the above-mentioned ester compound, the bisphenol-type epoxy compound obtained by making bisphenol A or bisphenol F and epichlorohydrin react is mentioned, for example. Commercially available compounds may be used as such compounds. For example, ZAR-1035, ZFR-1185 (above, Nippon Kayaku Co., Ltd., trade name), GY-260, GY-255, XB-2615 (above, Epoxy compounds such as bisphenol A type, bisphenol F type, hydrogenated bisphenol A type, brominated bisphenol A type, amino group-containing, alicyclic or polybutadiene modified, such as those manufactured by Ciba Geigy Japan Ltd., are suitably used.

  In addition to bisphenol-type epoxy compounds, novolak-type epoxy compounds obtained by further reacting epichlorohydrin with novolak compounds obtained by reacting phenol, cresol, halogenated phenol or alkylphenol compounds with formaldehyde under an acidic catalyst, (E) It is suitable as a raw material for obtaining a component. As such an epoxy compound, for example, PCR-1050, EOCN-120, BREN (above, Nippon Kayaku Co., Ltd., trade name), YDCN-701, YDCN-704, YDPN-638, YDPN-602 (above, Toto Kasei Co., Ltd., trade name), DEN-431, DEN-439 (above, Dow Chemical Co., trade name), EPN-1299 (Ciba Geigy, trade name), N-730, N-770, N- 865, N-665, N-673, VH-4150, VH-4240 (manufactured by Dainippon Ink & Chemicals, Inc., trade name) and the like.

  In addition to bisphenol type and novolak type, for example, salicylaldehyde-phenol or cresol type epoxy compounds such as EPPN502H, FAE2500 (above, Nippon Kayaku Co., Ltd., trade name) are preferably used as the epoxy compound. It is done. Alternatively, an epoxy compound having a polyamide skeleton or a polyamideimide skeleton can also be used. As such an epoxy compound, for example, Epicoat 828, Epicoat 1007, Epicoat 807 (above, Japan Epoxy Resin, trade name), Epicron 840, Epicron 860, Epicron 3050 (above, Dainippon Ink & Chemicals, Inc., Product name), DER-330, DER-337, DER-361 (above, product name manufactured by Dow Chemical Co., Ltd.), Celoxide 2021 (product name made by Daicel Chemical Industries, Ltd.), TETRAD-X, TETRAD-C (above , Mitsubishi Gas Chemical Co., Ltd., trade name), EPB-13, EPB-27 (above, Nippon Soda Co., Ltd., trade name) and the like, or those described in JP-A-8-260008, or these A mixture or a block copolymer is mentioned.

  As the above-mentioned unsaturated carboxylic acid, (meth) acrylic acid, crotonic acid, cinnamic acid, saturated or unsaturated dicarboxylic acid and (meth) acrylate having one hydroxyl group in one molecule or unsaturated monoglycidyl compound Or a carboxylic acid obtained by reacting a saturated or unsaturated polyvalent carboxylic acid anhydride with a (meth) acrylate having one hydroxyl group in one molecule, or saturated or Examples thereof include carboxylic acids obtained by further reacting a saturated or unsaturated polyvalent carboxylic acid anhydride with a carboxylic acid obtained by reacting an unsaturated dicarboxylic acid with an unsaturated monoglycidyl compound. More specifically, for example, phthalic acid, tetrahydrophthalic acid, hexahydrophthalic acid, maleic acid or succinic acid, hydroxyethyl (meth) acrylate, hydroxypropyl (meth) acrylate, tris (hydroxyethyl) isocyanurate di The compound obtained by making (meth) acrylate or glycidyl (meth) acrylate react by an equimolar ratio by a conventional method is mentioned as said unsaturated carboxylic acid. These unsaturated carboxylic acids can be used individually by 1 type or in mixture of 2 or more types. Among these, acrylic acid is preferable from the viewpoint of good photopolymerizability and heat resistance.

  Examples of the saturated or unsaturated polycarboxylic acid anhydride include anhydrides such as phthalic acid, tetrahydrophthalic acid, hexahydrophthalic acid, maleic acid, succinic acid, and trimellitic acid.

  Examples of the non-photosensitive polymer having a carboxyl group described above include an acrylic polymer and a phenoxy polymer. As an acrylic polymer, a polymerization initiator such as azobisisobutyronitrile, azobisdimethylvaleronitrile or benzoyl peroxide is used in an organic solvent to form a vinyl polymerizable polymer having a carboxyl group and a structure different from that. The polymer obtained by making it react with the vinyl polymerizable polymer which has it by normal solution polymerization can be used. Examples of the vinyl polymerizable polymer having a carboxyl group include acrylic acid, methacrylic acid, fumaric acid, cinnamic acid, crotonic acid, and itaconic acid. Examples of the vinyl polymerizable polymer having a structure different from that having a carboxyl group include methyl (meth) acrylate, ethyl (meth) acrylate, n-propyl (meth) acrylate, butyl (meth) acrylate, lauryl ( Examples include meth) acrylate, 2-ethylhexyl (meth) acrylate, vinyltoluene, N-vinylpyrrolidone, α-methylstyrene, 2-hydroxyethyl (meth) acrylate, acrylamide, acrylonitrile, and dimethylaminoethyl (meth) acrylate.

  The weight average molecular weight Mw of the polymer having a carboxyl group as the component (E) is preferably 3000 to 100,000, more preferably 5000 to 100,000, and more preferably 10,000 to 100,000 from the viewpoint of good fluidity and alkali developability. Is more preferable. From the same viewpoint, in particular, when the polymer having a carboxyl group is a non-photosensitive polymer, it is preferable to have Mw in the numerical range as described above. In addition, Mw in this specification shows what was measured in standard polystyrene conversion using gel permeation chromatography (GPC).

  What is necessary is just to adjust the acid value of the polymer which has a carboxyl group which is (E) component so that it may become an optimal numerical range with the kind etc. of the alkali developing solution to be used. In particular, when considering the balance of properties such as alkali developability and electrical properties, the acid value is preferably 30 to 250 mgKOH / g, more preferably 50 to 150 mgKOH / g.

  Further, the acid value of the solid content contained in the photosensitive resin composition of the present embodiment is preferably adjusted to 10 to 120 mgKOH / g from the same viewpoint, and is adjusted to 20 to 80 mgKOH / g. And more preferred.

  The content ratio of the component (E) in the photosensitive resin composition of the present embodiment is preferably 20 to 300 parts by mass with respect to 20 parts by mass of the component (A). When the content ratio of the component (E) is less than 20 parts by mass, the flowability of the photosensitive resin composition tends to be large and the tack tends to be strong, and when it exceeds 300 parts by mass, the mechanical properties tend to deteriorate.

  The photosensitive resin composition of this embodiment preferably contains an epoxy resin having two or more glycidyl groups per molecule as the component (F) from the viewpoint of good adhesion to metal and moisture resistance. Examples of such component (F) include bisphenol A type epoxy resin, bisphenol F type resin, brominated bisphenol A type epoxy resin, novolac type epoxy resin, biphenyl type epoxy resin, bisphenol S type epoxy resin, and triglycidyl isocyanate. And complex dry epoxy resins. In addition, as commercially available products, ESLV-80XY (manufactured by Nippon Steel Chemical Co., Ltd., trade name), YDCN-701, YDCN-704, YDPN-638, YDPN-602 (above, trade name, manufactured by Tohto Kasei Co., Ltd.), Epicron 840, Epicron 860, N-730, N-770, N-865, N-665, N-673 (above, Dainippon Ink & Chemicals, trade name), DEN-431, DEN-330, DEN-337 (above , Manufactured by Dow Chemical Co., Ltd.).

  The content rate of the (F) component in the photosensitive resin composition of this embodiment is preferable in it being 5-100 mass parts with respect to 20 mass parts of (A) component. When the content ratio of the component (F) is less than 5 parts by mass, the mechanical properties tend to decrease, and when it exceeds 100 parts by mass, the cured product of the photosensitive resin composition becomes brittle and the mechanical properties tend to decrease. is there.

  In the photosensitive resin composition of the present embodiment, the component (A) is used as long as the effect obtained by the present invention is not inhibited from the viewpoint of starting the curing reaction of the component (A) under desired conditions and proceeding more rapidly. It is preferable to further contain an organic peroxide other than those described above. As the component (G), it is preferable that a radical can be generated at a temperature at which the curing reaction of the component (A) is desired to start. Examples of such component (G) include t-butylcumyl peroxide, dicumyl peroxide, α, α′-bis (t-butylperoxy-m-isopropyl) benzene, and 2,5-dimethyl-2. , 5-di (t-butylperoxy) hexane, 2,5-dimethyl-2,5-di (t-butylperoxy) hexyne-3, azobisisobutyronitrile, di-t-butyl peroxide, An acetyl peroxide etc. are mentioned. Among these, from the viewpoint of storage stability and curability, an organic peroxide having a relatively high decomposition temperature is preferable as the component (G), and examples of such an organic peroxide include t-butylcumyl peroxide, Dicumyl peroxide, α, α′-bis (t-butylperoxy-m-isopropyl) benzene, 2,5-dimethyl-2,5-di (t-butylperoxy) hexane, 2,5-dimethyl- An example is 2,5-di (t-butylperoxy) hexyne-3.

  The blending ratio of the component (G) in the photosensitive resin composition of the present embodiment is preferably 0.1 to 10 parts by mass, and 0.4 to 5 parts by mass when the component (A) is 20 parts by mass. More preferably. When the blending ratio of the component (G) is less than 0.1 parts by mass, the time required for curing becomes long, so that the cured state of the obtained cured product tends to be non-uniform. When the blending ratio of the component (G) exceeds 10 parts by mass, it tends to fire at the time of curing, and the curability of the cured product tends to decrease due to the organic peroxide remaining without being decomposed. .

  If the photosensitive resin composition of this embodiment further contains a melamine compound, a triazine compound, or a derivative thereof as an adhesion improver, it is preferable from the viewpoint of improving the adhesion of the obtained cured product to a metal such as copper. Examples of the adhesion improver include melamine, acetoguanamine, benzoguanamine, melamine-phenol-formalin resin, ethyldiamino-S-triazine, 2,4-diamino-S-triazine, 2,4-diamino-6-xylyl- S-triazine etc. are mentioned. Examples of commercially available products include 2MZ-AZINE, 2E4MZ-AZINE, C11Z-AZINE, 2MA-OK (trade name, manufactured by Shikoku Kasei Kogyo Co., Ltd.). These adhesion improvers not only improve the PCT resistance by increasing the adhesion between the photosensitive resin composition layer and a metal circuit such as copper, but also exhibit the effect of improving the electrolytic corrosion resistance. These adhesion improvers are contained in an amount of 0.1 to 10% by mass based on the total amount of the photosensitive resin composition from the viewpoint of improving the adhesion to such an extent that the other functions of the photosensitive resin composition are not impaired. It is preferable.

  The photosensitive resin composition of the present embodiment comprises barium sulfate, barium titanate, powdered silicon oxide, amorphous silica, talc, clay, calcined kaolin, magnesium carbonate, calcium carbonate, aluminum oxide, aluminum hydroxide as necessary. Inorganic fillers such as mica powder are preferable from the viewpoint of cost reduction. When using these inorganic fillers, the blending ratio in the photosensitive resin composition is 70% by mass or less, so as not to impair each function of the photosensitive resin composition according to the present embodiment described above or below. It is preferable from the viewpoint of improving the adhesion with other members of the obtained cured product, curability, and the like.

  The photosensitive resin composition of the present embodiment may further include colorants such as phthalocyanine blue, phthalocyanine green, iodine green, disazo yellow, crystal violet, titanium oxide, carbon black, naphthalene black, hydroquinone, hydroquinone monomethyl, if necessary. Polymerization inhibitors such as ether, tert-butylcatechol, pyrogallol and phenothiazine, thixotropic agents such as benton, montmorillonite, aerosil and amide wax, antifoaming agents such as silicone compounds, fluorine compounds and polymers, leveling agents, or imidazole You may contain various additives like adhesion imparting agents, such as a compound, a thiazole compound, a triazole compound, and a silane coupling agent.

  The photosensitive resin composition of the present embodiment may be aliphatic alcohols such as methanol, ethanol, n-propanol, i-propanol, n-butanol, n-pentanol, hexanol, benzyl alcohol, cyclohexane, etc., if necessary. Hydrocarbon, diacetone alcohol, 3-methoxy-1-butanol, acetone, methyl ethyl ketone, methyl propyl ketone, diethyl ketone, methyl isobutyl ketone, methyl pentyl ketone, methyl hexyl ketone, ethyl butyl ketone, dibutyl ketone, cyclopentanone, cyclohexanone Γ-butyrolactone, 3-hydroxy-2-butanone, 4-hydroxy-2-pentanone, 6-hydroxy-2-hexanone, ethylene glycol, diethylene glycol, triethylene glycol, teto Ethylene glycol, propylene glycol, ethylene glycol monoacetate, ethylene glycol diacetate, propylene glycol monoacetate, propylene glycol diacetate, methyl cellosolve, ethyl cellosolve, butyl cellosolve, phenyl cellosolve, ethylene glycol dimethyl ether, ethylene glycol diethyl ether, ethylene glycol dibutyl ether , Ethylene glycol alkyl ether compounds such as methyl cellosolve acetate and ethyl cellosolve acetate or acetate thereof, diethylene glycol monoalkyl ether compound or acetate thereof, diethylene glycol dialkyl ether compound, triethylene glycol alkyl ether compound, propylene glycol amine Alkyl ether compound or its acetate, dipropylene glycol alkyl ether compound, toluene, ethyl formate, propyl formate, butyl formate, amyl formate, methyl acetate, ethyl acetate, propyl acetate, butyl acetate, methyl propionate, ethyl propionate, methyl butyrate , Carboxylic acid ester compounds such as ethyl butyrate, dimethylformamide, dimethyl sulfoxide, dioxane, tetrahydrofuran, methyl lactate, ethyl lactate, methyl benzoate, ethyl benzoate, propylene carbonate, etc. It can melt | dissolve and a viscosity can be adjusted suitably.

  As for the photosensitive resin composition of this embodiment demonstrated above, the hardened | cured material obtained by hardening it has a sufficiently high tensile strength compared with the conventional one. Furthermore, the cured product obtained from the photosensitive resin composition has excellent thermal shock resistance, good peelability when in close contact with other members, PCT resistance, electric corrosion resistance, Ni / Au plating resistance, and It tends to have solder heat resistance.

  Moreover, in the photosensitive resin composition containing the conventional epoxy resin, the high acid value polymer (for example, polymer which has a carboxyl group) and epoxy resin which are contained in order to perform favorable alkali image development are easy at room temperature. Since it reacts, the product is often sold in two parts (an epoxy resin-containing solution and a high acid value polymer-containing solution) so that it can be avoided. However, since the pot life when mixing two liquids is as short as several hours to one day, there are restrictions on the use conditions, and when two liquids are mixed in advance to form a film, it is difficult to store them in a film state. It was. However, since the photosensitive resin composition of this embodiment is sufficiently excellent in storage stability at room temperature by containing each of the above-described materials, it can be made into one liquid or a film relatively easily.

  The photosensitive resin composition described above includes an epoxy resin and a liquid composition that does not contain a polymer having a carboxyl group, and a liquid composition that does not contain an epoxy resin and contains a polymer having a carboxyl group. These liquid compositions may be mixed and cured before curing.

  The photosensitive resin composition of the present invention is particularly useful as a rigid resist and flexible printed wiring board, and a solder resist for packages such as BGA, CSP and TCP, or a build-up material for multilayer materials. It can also be used for coating materials such as glass, ceramic, plastic and paper.

  Next, preferred embodiments of the photosensitive film for permanent resist of the present invention will be described. FIG. 1 is a schematic cross-sectional view showing a photosensitive film for permanent resist of this embodiment. A photosensitive film 1 for permanent resist shown in FIG. 1 includes a support 11, a photosensitive resin composition layer 12 made of the photosensitive resin composition formed on the support, and a photosensitive resin composition layer 12. And a cover film 13 laminated thereon.

  As the support 11, a plastic film is used, and it is preferable to use a plastic film such as a polyester film such as polyethylene terephthalate, a polyimide film, a polyamideimide film, a polypropylene film, or a polystyrene film. Here, about the thickness of a support body, it selects suitably in the range of 10-150 micrometers.

  The photosensitive resin composition layer 12 is made of the photosensitive resin composition. There is no restriction | limiting in particular about the thickness, It selects suitably in the range of 10-150 micrometers. The photosensitive resin composition layer 12 is formed by coating the photosensitive resin composition on the support 11 with a uniform thickness using a comma coater, blade coater, lip coater, rod coater, squeeze coater, reverse coater, transfer roll coater, etc. -It can be formed by drying and volatilizing the solvent.

  Examples of the cover film 13 include a polyethylene film, a polypropylene film, a Teflon (registered trademark) film, and a surface-treated paper. The cover film 13 only needs to have a smaller adhesive force between the photosensitive resin composition layer 12 and the cover film 13 than the adhesive force between the photosensitive resin composition layer 12 and the support 11.

  When storing the photosensitive film for permanent resist, it is preferable that the peelable cover film 13 for protecting the adhesive surface is stacked and wound.

  The photosensitive resin composition layer 12 can be easily formed on the substrate or the wiring board by stacking the photosensitive resin composition layer 12 on the substrate or the printed wiring board and pasting them together using a hot roll laminator or the like. There is no restriction | limiting in particular about the thickness of this photosensitive resin composition layer 12, Usually, it selects suitably in the range of 10-150 micrometers.

  Exposure and development of the formed photosensitive resin composition layer 12 can be performed by a conventional method. For example, an ultrahigh pressure mercury lamp, a high pressure mercury lamp, or the like is used as a light source, and imagewise exposure can be performed through a negative mask directly on the photosensitive resin composition layer 12 or through a transparent film such as a polyethylene terephthalate film. When the transparent film remains after exposure, it is preferable to develop the film after peeling it off.

  The photosensitive resin composition layer 12 can also be formed with an image resin film by a printing method, a laser drilling method using a carbon dioxide gas laser, a YΑG laser, an excimer laser, or the like.

  The above-described photosensitive film for permanent resist can form a cured film having sufficiently high tensile strength as compared with the conventional one, and is excellent in storage stability in a one-pack type or film state.

  Subsequently, a preferred embodiment of the resist pattern forming method of the present invention will be described. In the resist pattern forming method of the present embodiment, the photosensitive resin is formed so as to cover a conductor layer on an insulating substrate of a laminated substrate having an insulating substrate and a conductor layer having a circuit pattern formed on the insulating substrate. Forming a photosensitive resin composition layer comprising the composition, irradiating a predetermined portion of the photosensitive resin composition layer with actinic rays to form an exposed portion, and then removing portions other than the exposed portion; is there.

  As a method for forming the photosensitive resin composition layer, the photosensitive resin composition of the present embodiment is directly applied, or the photosensitive resin composition layer in the photosensitive film for permanent resist is heated on the insulating substrate while heating. The formation method which carries out pressure bonding and laminates can be illustrated. Therefore, when the photosensitive resin composition contains a volatile component such as a solvent, the photosensitive resin composition layer formed on the substrate is mainly composed of components after most of the solvent is removed.

  Thereafter, an exposed portion is formed by irradiating a predetermined portion of the photosensitive resin composition layer with actinic rays. Examples of the method for forming the exposed portion include a method of irradiating an image with active light through a negative or positive mask pattern called an artwork. At this time, the mask may be directly contacted on the photosensitive resin composition, or may be contacted via a transparent film.

  As the light source of actinic light, a known light source such as a carbon arc lamp, a mercury vapor arc lamp, an ultrahigh pressure mercury lamp, a high pressure mercury lamp, or a xenon lamp that emits ultraviolet rays effectively is used. Moreover, what emits visible light effectively, such as a photographic flood light bulb and a solar lamp, is also used.

After the exposure, an alkaline aqueous solution (alkaline developer) is used, and development is performed by removing portions other than the exposed portion by a known method such as spraying, rocking immersion, brushing, and scraping, thereby forming a resist pattern. Note that after the resist pattern is formed, post-curing may be further performed by exposure at 1 to 5 J / cm ² or / and heating at 100 to 200 ° C. for 30 minutes to 12 hours (post-heating step).

  The developer used in the development process is an alkali developer as a standard, but there is no particular limitation on the type of the developer as long as it does not damage the exposed part and selectively elutes the unexposed part. It is determined depending on the development type of the composition, and common ones such as a semi-aqueous developer and a solvent developer can be used. For example, an emulsion developer containing water and an organic solvent as described in JP-A-7-234524 can be used. Particularly useful emulsion developers include, for example, propylene glycol monomethyl ether acetate, ethylene glycol ethyl ether acetate, 2,2-butoxyethoxyethanol, butyl lactate, cyclohexyl lactate, ethyl benzoate, and 3-methyl-3 as organic solvent components. An emulsion developer containing 10 to 40% by mass of an organic solvent such as methoxybutyl acetate can be mentioned. When an alkaline developer is used, an alkaline aqueous solution such as potassium hydroxide, sodium hydroxide, sodium carbonate, potassium carbonate, sodium phosphate, sodium silicate, 4-sodium borate, ammonia, amines and the above organic solvent are used. It is also possible to use an emulsion developer.

  By the above-described method, a resist pattern can be formed on the photosensitive resin composition layer laminated on the conductor layer on which the circuit pattern is formed. The photosensitive resin composition layer on which the resist pattern is formed can be used as a solder resist for preventing solder from adhering to unnecessary portions on the conductor layer at the time of mounting components.

  Since the above-described solder resist uses the photosensitive resin composition of the present embodiment or the photosensitive film for permanent resist, the mechanical properties, particularly the tensile strength, are sufficiently high.

  Next, a preferred embodiment of the printed wiring board of the present invention will be described. FIG. 2 is a schematic cross-sectional view showing the printed wiring board of the present embodiment. The printed wiring board 2 shown in FIG. 2 has an insulating substrate 22, a conductor layer 23 having a circuit pattern formed on one surface of the insulating substrate 22, and a circuit pattern formed on the other surface of the insulating substrate 22. And a permanent resist layer 24 formed on the insulating substrate 22 so as to cover the conductor layer 23 having a circuit pattern. The permanent resist layer 24 is made of a cured product of the photosensitive resin composition, and the permanent resist layer 24 has an opening 26 so that at least a part of the conductor layer 23 having a circuit pattern is exposed. .

  Since the printed wiring board 2 has the opening 26, a mounting component such as CSP or BGA can be joined to the conductor layer 23 having a circuit pattern by solder or the like, and so-called surface mounting becomes possible. The permanent resist layer 24 has a role as a solder resist for preventing the solder from adhering to unnecessary portions of the conductor layer during soldering for joining, and after the mounting parts are joined. Functions as a permanent mask for protecting the conductor layer.

  Next, an example of a method for manufacturing the printed wiring board 2 will be schematically described. FIG. 3 is a process diagram schematically showing a method of manufacturing the printed wiring board 2 shown in FIG. 3A shows an insulating substrate 22 having a conductor layer 23 having a circuit pattern on one side and a conductor layer 21 having no circuit pattern on the other side. FIG. 3B and FIG. And (d) are the printed wiring board 4 after laminating the photosensitive resin composition layer 24 on the insulating substrate 22, the state of irradiating the photosensitive resin composition layer 24 with actinic rays, and the print after development, respectively. The wiring board 2 is shown.

  First, the pattern of the conductor layer 23 is formed on the insulating substrate 22 as shown in FIG. 3A by a known method or the like for etching one side of a double-sided metal laminate (for example, double-sided copper-clad laminate). The printed wiring board 3 on which the conductor layer 23 is formed is obtained. Next, as shown in FIG. 3B, on the double-sided metal-clad laminate 3 on which the conductor layer 23 is formed, the photosensitivity of the photosensitive film for permanent resist according to this embodiment so as to cover the conductor layer 23. The photosensitive resin composition layer 24 which consists of a resin composition is formed, and the printed wiring board 4 in which the photosensitive resin composition layer 24 was formed is obtained. Next, a predetermined portion of the photosensitive resin composition layer 24 is irradiated by irradiating the photosensitive resin composition layer 24 laminated as shown in FIG. 3C with actinic rays through the mask 5 having a predetermined pattern. Is cured. Finally, the printed wiring board 2 is obtained by removing a non-exposed portion (for example, alkali development) to form a permanent resist layer 24 having an opening 26 as shown in FIG. When the photosensitive resin composition contains a volatile component such as an organic solvent, the permanent resist layer 24 is a cured product of the photosensitive resin composition after most of the volatile component is removed. .

  In addition, lamination | stacking of the photosensitive resin composition layer 24 on the insulated substrate 22, irradiation of actinic light, and removal of an unexposed part can be performed by the method similar to the case in the formation method of the above-mentioned resist pattern.

  The permanent resist layer 24 in the printed wiring board 2 thus obtained is made of a cured product of the photosensitive resin composition of the present embodiment, and is particularly excellent in mechanical properties such as tensile strength. , Solder heat resistance and Ni / Au plating resistance tend to be excellent.

  The preferred embodiment of the present invention has been described above, but the present invention is not limited to the above embodiment. For example, the photosensitive resin composition of the present invention can also be used to form photo vias that are one type of micro vias. That is, after the photosensitive resin composition layer according to the present invention is formed on the core substrate, a photovia is formed by batch exposure and development by irradiation with light such as UV using a mask. Since the photovia is formed from the photosensitive resin composition of the present invention, the mechanical properties, particularly the tensile strength, are sufficiently high.

  Moreover, the above-mentioned photosensitive resin composition, the photosensitive film for permanent resists, a printed wiring board, etc. can be used for a semiconductor package similarly to the conventional photosensitive resin composition. A semiconductor package formed using the photosensitive resin composition or the like of the present invention is sufficiently excellent in mechanical properties, and further tends to be excellent in thermal shock resistance and electric corrosion resistance.

  EXAMPLES Hereinafter, although an Example demonstrates this invention further in detail, this invention is not limited to these Examples.

Example 1
Each component shown in Table 1 was mixed at a blending ratio (unit: parts by mass) described in the column of Example 1 in Table 2 to prepare a liquid photosensitive resin composition according to Example 1. Next, the photosensitive resin composition is uniformly coated on a polyethylene terephthalate (PET) film having a film thickness of 16 μm, dried by a hot air convection dryer at 95 ° C. for 10 minutes to remove the solvent, and the photosensitive resin. A composition layer was formed. Then, the 25-micrometer-thick polyethylene film was stuck on the said photosensitive resin composition layer as a protective film, and the photosensitive film which concerns on Example 1 was obtained. In addition, the film thickness after drying of the photosensitive resin composition was 30 micrometers.

(Examples 2-4, Comparative Examples 1-3)
In the same manner as in Example 1 except that the components shown in Table 1 were mixed at the blending ratios described in the columns of Examples 2 to 4 and Comparative Examples 1 to 3 in Table 2, Examples 2 to 4, The photosensitive film which concerns on Comparative Examples 1-3 was obtained.

<Production of evaluation substrate>
Then, the evaluation board | substrate which concerns on Examples 1-4 and Comparative Examples 1-3 was formed using each above-mentioned photosensitive film. Hereinafter, a method for producing the evaluation substrate will be described.

  First, etching is performed on a glass cloth base epoxy resin double-sided copper-clad laminate [Hitachi Kasei Kogyo Co., Ltd. trade name MCL-E-679 (trade name) having a copper foil thickness of 18 μm and double-sided roughened foil on both sides]. The printed wiring board (circuit board) which has applied and has a conductor layer (henceforth a circuit layer) on both surfaces was produced. Next, after peeling off the polyethylene film of the above-described photosensitive film, the photosensitive film was pressed using a press-type vacuum laminator (trade name: MVLP-500, manufactured by Meiki Seisakusho Co., Ltd.) with an upper plate temperature of 50 ° C. Under the conditions of a plate temperature of 50 ° C., a degree of vacuum of 5 hPa or less, and a press time of 30 seconds, a laminate is obtained by thermocompression bonding with one side of the circuit board facing the photosensitive resin composition layer side. It was.

  The resulting laminate was allowed to stand at room temperature in the atmosphere for 1 hour or longer, and then a phototool having a stove 21-step tablet (manufactured by Eastman Kodak Company) and a line width / space width of 6/400 to 47 / A photo tool having a wiring pattern of 400 (unit: μm) is brought into close contact with the laminated PET film, and the remaining 21-step tablet is left using an exposure machine (trade name: HMW-201GX, manufactured by Oak Manufacturing Co., Ltd.). The exposure was performed with an energy amount of 8 steps.

After the exposure, the laminate was further allowed to stand in the atmosphere at room temperature for 10 minutes, and then the PET film was peeled off and sprayed onto the photosensitive resin composition layer with a 1% by mass aqueous sodium carbonate solution at 30 ° C. for 40 seconds, and the unexposed part. The film was removed and developed. The laminate obtained after development was irradiated with 1 J / cm ² of ultraviolet rays using an ultraviolet irradiation device (trade name: QRM-2317-F-00, manufactured by Oak Manufacturing Co., Ltd.), and then at 160 ° C. in the air. The evaluation board | substrate which performed the heat processing for 1 hour and formed the permanent resist layer according to Examples 1-4 and Comparative Examples 1-3 was obtained.

<Evaluation of solder heat resistance>
After applying a rosin flux (MH-820V, manufactured by Tamura Kaken Co., Ltd., trade name) to the evaluation substrate obtained as described above, it was immersed in a solder bath at 260 ° C. for 10 seconds and then taken out from the solder bath. The operation was repeated three times to perform soldering. Thus, the floating, swelling, and peeling degree of the permanent resist layer of the evaluation substrate on which the solder plating was performed were visually observed and evaluated according to the following criteria. That is, “A” indicates that the permanent resist layer could not be lifted, swollen, or peeled off, and “B” indicates that any of them could be confirmed. The results are shown in Table 3.

<Evaluation of electroless Ni / Au plating resistance>
The obtained evaluation substrate was immersed in an 85 ° C. plating bath containing an electroless Ni plating solution (Melplate NI-865T, manufactured by Meltex, Inc., trade name) for 15 minutes, followed by electroless Au plating solution ( The plate was immersed for 10 minutes in a 90 ° C. plating tank containing Melplate AU-601 (trade name, manufactured by Meltex). Thus, the floating, swelling and peeling degree of the permanent resist layer of the evaluation substrate on which the electroless Ni / Au plating was applied were visually observed and evaluated according to the following criteria. That is, “A” indicates that the permanent resist layer could not be lifted, swollen, or peeled off, and “B” indicates that any of them could be confirmed. The results are shown in Table 3.

<Evaluation of PCT resistance (high temperature and humidity resistance)>
The obtained evaluation substrate was allowed to stand in an atmosphere of 121 ° C., 100% RH, 2.1 atm for 100 hours, and then the degree of floating, swelling, and peeling of the permanent resist layer was visually observed and evaluated according to the following criteria. did. That is, “A” indicates that the permanent resist layer could not be lifted, swollen, or peeled off, and “B” indicates that any of them could be confirmed. The results are shown in Table 3.

<Evaluation of thermal shock resistance>
The obtained evaluation substrate was exposed to 55 ° C. air for 15 minutes, then heated at a rate of 180 ° C./min, then exposed to 125 ° C. air for 15 minutes, and then 180 ° C./min. The thermal cycle of lowering the temperature at a temperature lowering rate was repeated 1000 times. The crack and peeling degree of the permanent resist layer of the evaluation substrate after being exposed to such an environment were observed with a 100-fold metal microscope and evaluated according to the following criteria. That is, “A” indicates that the permanent resist layer could not be cracked and peeled, and “B” indicates that any of them could be confirmed. The results are shown in Table 3.

<Evaluation of electric corrosion resistance>
After connecting the polytetrafluoroethylene shield wire to the conductor layer with Sn / Pb solder so that a voltage was applied to the conductor layers on both sides of the obtained evaluation board, a voltage of 5 V was applied to the evaluation board. In this state, the evaluation substrate was allowed to stand in a super accelerated high temperature high humidity life test (HAST) bath at 131 ° C. and 85% RH for 100 hours. Subsequent migration, swelling, and peeling of the permanent resist layer of the evaluation substrate were observed with a 100-fold metal microscope and evaluated according to the following criteria. That is, “A” indicates that the migration, swelling and peeling of the permanent resist layer could not be confirmed, and “B” indicates that any of them could be confirmed. The results are shown in Table 3.

<Evaluation of storage stability>
After the photosensitive films according to Examples 1 to 4 and Comparative Examples 1 to 3 were left in the atmosphere at 25 ° C. for 1 month, an evaluation substrate on which a permanent resist layer was formed was obtained in the same manner as the above-described evaluation substrate. . The pattern of the permanent resist layer of the evaluation substrate was observed with a stereomicroscope and evaluated according to the following criteria. That is, “A” indicates that the remaining of the photosensitive resin composition could not be confirmed in the unexposed portion of the permanent resist layer, and “B” indicates that the remaining of the photosensitive resin composition could be confirmed. The results are shown in Table 3.

<Evaluation of physical properties of cured film>
The cured film which hardened the photosensitive resin composition layer by exposing and heating the photosensitive film which concerns on Examples 1-4 and Comparative Examples 1-3 on the conditions similar to the above was obtained. Tg of the cured film was measured by TMA. Moreover, the tensile strength and elongation rate of the cured film were measured according to JIS K 7127 “Plastic Film and Sheet Tensile Test Method”. The results are shown in Table 3.

It is a schematic cross section which shows one Embodiment of the photosensitive film for permanent resists. It is a schematic cross section showing one embodiment of a printed wiring board. (A)-(d) is process drawing which shows the manufacturing method of the printed wiring board 2 shown in FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Photosensitive film for permanent resists 2, 3, 4 ... Printed wiring board, 5 ... Photomask, 11 ... Support body, 12 ... Photosensitive resin composition layer, 13 ... Cover film, 21 ... It does not have a circuit pattern Conductor layer, 22 ... insulating substrate, 23 ... conductor layer having a circuit pattern, 24 ... permanent resist layer, 26 ... opening.

Claims (11)

(A) component: a cyclic curing agent that can be ring-opened by heating and cross-linked by itself;
(B) component; a block curing agent having a group derived from a blocking agent in the molecule and capable of dissociating the group derived from the blocking agent by heating,
(C) component; a photopolymerizable compound having an ethylenically unsaturated bond; and (D) component; a photopolymerization initiator,
The photosensitive resin composition containing this.   The photosensitive resin composition of Claim 1 whose said (A) component is a bismaleimide compound.   The photosensitive resin composition of Claim 1 or 2 whose said (B) component is a blocked isocyanate compound.   The photosensitive resin composition as described in any one of Claims 1-3 in which the said (C) component has a 2 or more (meth) acryloyloxy group per molecule.   (E) component; The photosensitive resin composition as described in any one of Claims 1-4 which further contains the polymer which has a carboxyl group.   The photosensitive resin composition according to claim 5, wherein the component (E) has an ethylenically unsaturated bond and has a weight average molecular weight of 3000 to 100,000.   The photosensitive resin composition of Claim 5 or 6 which contains solid content and whose acid value of the solid content is 10-150 mgKOH / g.   The component (B) is 10 to 50 parts by mass, the component (C) is 10 to 100 parts by mass, and the component (D) is 0.1 to 20 parts by mass with respect to 20 parts by mass of the component (A). The photosensitive resin composition as described in any one of Claims 1-7 which contains.   A photosensitive film for permanent resist, comprising: a support; and a photosensitive resin composition layer containing the photosensitive resin composition according to any one of claims 1 to 8 formed on the support. .   The photosensitive as described in any one of Claims 1-8 so that the said conductor layer may be covered on the said insulated substrate of a laminated substrate provided with the insulated substrate and the conductor layer which has a circuit pattern formed on this insulated substrate. Forming a photosensitive resin composition layer comprising a photosensitive resin composition, irradiating a predetermined portion of the photosensitive resin composition layer with an actinic ray to form an exposed portion, and then forming the exposed portion of the photosensitive resin composition layer A method for forming a resist pattern, wherein a portion other than an exposed portion is removed. A printed wiring board comprising an insulating substrate, a conductor layer having a circuit pattern formed on the insulating substrate, and a permanent resist layer formed on the insulating substrate so as to cover the conductor layer,
The said permanent resist layer consists of a hardened | cured material of the photosensitive resin composition as described in any one of Claims 1-8, and the said permanent resist layer is such that a part of said conductor layer is exposed. A printed wiring board having an opening.

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