JP2013218146A - Photosensitive resin composition for protective film - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a photosensitive resin composition for a protective film having excellent heat resistance and a low thermal expansion coefficient and achieving good resolution of a via hole and electric reliability.SOLUTION: The photosensitive resin composition comprises (A) an acid-modified vinyl group-containing epoxy resin, (B) a photopolymerizable monomer having an ethylenically unsaturated bond, (C) a photopolymerization initiator, and (D) an inorganic filler. The (A) component includes a resin (A') obtained by allowing an epoxy resin (a) as a mixture of a novolac epoxy resin and a bisphenol novolac resin to react with a vinyl group-containing monocarboxylic acid (b) and further by allowing the resultant resin to react with a saturated or unsaturated group-containing polybasic acid anhydride. The content of the (D) inorganic filler is 20 mass% or more and 60 mass% or less with respect to the whole solid content.

Description

  The present invention relates to an alkali-developable photosensitive resin composition for a protective film of a printed wiring board, and more specifically, in the resist field of a substrate for a semiconductor package, the photosensitive film photosensitive film used as a permanent mask resist. The present invention relates to a functional resin composition.

  In the field of printed wiring boards, conventionally, a permanent mask resist (protective film) is formed on a printed wiring board. As a method for forming a pattern of a photosensitive resist, a colored photosensitive resin composition is applied to a substrate, dried, and then cured by selectively irradiating with ultraviolet rays, and then only an uncured portion is developed with an alkaline solution or the like. A photolithography method in which pattern formation is performed by removing the mainstream. This permanent mask resist has a role of preventing the solder from adhering to unnecessary portions of the conductor layer of the printed wiring board in the process of flip chip mounting the semiconductor element on the printed wiring board via solder. Further, the permanent mask resist has a role of preventing corrosion of the conductor layer and maintaining electrical insulation between the conductor layers when the printed wiring board is used.

  Conventionally, permanent mask resists in the production of printed wiring boards have been produced by methods such as screen printing or roll coating with thermosetting or photosensitive resin compositions.

  For example, in a flexible wiring board using mounting methods such as FC (Flip Chip), TAB (Tape Automated Bonding), and COF (Chip On Film), a rigid wiring board, an IC chip, an electronic component, or an LCD panel and a connection wiring pattern portion. The permanent mask resist is formed by screen-printing and thermosetting the thermosetting resin paste (see, for example, Patent Document 1).

  In recent years, with the increase in the density of wiring patterns, permanent mask resists are required to have high resolution, and photosensitive resin compositions that form patterns by photographic methods are actively used. Among them, the alkali development type that can be developed with a weak alkaline aqueous solution such as an aqueous sodium carbonate solution has become the mainstream from the viewpoint of working environment preservation and global environment preservation. In addition, along with the trend toward miniaturization and higher performance of electronic equipment, the tendency of higher density due to the narrower pitch of the wiring of the semiconductor chip is remarkable, and as a semiconductor mounting method corresponding to this, solder bumps are used to connect the semiconductor chip and the substrate. The flip chip connection method that joins the mainstream is the mainstream. This flip chip connection method is a semiconductor mounting method by a reflow method in which solder balls are arranged between a substrate and a semiconductor chip and the whole is heated and melt bonded. For this reason, the board itself is exposed to a high temperature environment during solder reflow, and due to thermal contraction of the board, a large stress is generated in the solder balls that connect the board and the semiconductor, resulting in poor wiring connection, cracks in the permanent mask resist and underfill (cracking). ) May occur. Therefore, an insulating material used for a printed wiring board is required to have a low thermal expansion coefficient.

  Furthermore, in recent years, high melting point solder that does not use lead has become mainstream due to laws and regulations for environmental problems, etc., and this lead-free solder has a use temperature that is about 20-40 ° C. higher than conventional eutectic solder, Photosensitive thermosetting resin compositions are required to have higher heat resistance than ever before.

As described above, insulating materials for printed wiring boards are required to have high heat resistance and low thermal expansibility. As an epoxy resin material that can meet such demands, for example, a tetrafunctional type represented by the formula (1) Naphthalene-based epoxy resins are known (see Patent Document 2).

  However, the tetrafunctional naphthalene-based epoxy resin has a higher crosslinking density than a general phenol novolac epoxy resin, and exhibits an excellent low thermal expansion coefficient and heat resistance in a cured epoxy resin, but is more favorable. Realization of via resolution and electrical reliability is required, and further improvements are required. Furthermore, since the tetrafunctional naphthalene-based epoxy resin has low solubility in a solvent generally used in the production of printed wiring boards, the properties of the cured product are not sufficiently exhibited.

JP 2003-198105 A Japanese Patent No. 3137202

  Therefore, the problem to be solved by the present invention is to provide a photosensitive resin composition that has excellent heat resistance and low thermal expansion coefficient, and that realizes better via resolution and electrical reliability.

  In order to achieve the above object, the present invention provides (A) an acid-modified vinyl group-containing epoxy resin, (B) a photopolymerizable monomer having an ethylenically unsaturated bond, (C) a photopolymerization initiator, (D) inorganic It is a photosensitive resin composition containing a filler, the component (A) contains the compounds represented by the general formula (2) and the general formula (3), and (D) the content of the inorganic filler is all Provided is a photosensitive resin composition for a protective film of a printed wiring board for a semiconductor package, wherein the content is 20% by mass to 60% by mass with respect to the solid content.

As a result of repeated studies on the solder resist characteristics and composition satisfying these high heat resistance, low thermal expansion coefficient, good via resolution and electrical reliability, (A) acid-modified vinyl group-containing epoxy resin It was found that heat resistance, low thermal expansion coefficient, and electrical reliability can be achieved without reducing via resolution by applying a resin composition having high heat resistance and containing 20 to 60% by mass of an inorganic filler.
That is, the present invention relates to the following.
<1> Photosensitive resin containing (A) acid-modified vinyl group-containing epoxy resin, (B) a photopolymerizable monomer having an ethylenically unsaturated bond, (C) a photopolymerization initiator, and (D) an inorganic filler. It is a composition, and the component (A) includes a compound represented by the following general formula (2) and a compound represented by the following general formula (3) or (4), and the (D) inorganic The photosensitive resin composition whose content of a filler is 20 to 60 mass% with respect to the total amount of solids.

［式（２）中、Ｒ^１１は水素原子又はメチル基を示し、Ｙ^１は水素原子又はグリシジル基を示し、ｎ１は１以上の整数を示す。なお、複数存在するＲ^１１及びＹ^１はそれぞれ同一でも異なっていてもよい。但し、少なくとも一つのＹ^１はグリシジル基を示す。］

[In Formula (2), R ¹¹ represents a hydrogen atom or a methyl group, Y ¹ represents a hydrogen atom or a glycidyl group, and n 1 represents an integer of 1 or more. A plurality of R ¹¹ and Y ¹ may be the same or different. However, at least one Y ¹ represents a glycidyl group. ]

［式（３）中、Ｒ^１２は水素原子又はメチル基を示し、Ｙ^２は水素原子又はグリシジル基を示す。なお、２つのＲ^１２は同一でも異なっていてもよく、２つのＹ^２は同一でも異なっていてもよい。但し、Ｙ^２の少なくとも一方はグリシジル基を示す。］

[In the formula (3), R ¹² represents a hydrogen atom or a methyl group, and Y ² represents a hydrogen atom or a glycidyl group. Two R ¹² may be the same or different, and two Y ² may be the same or different. However, at least one of Y ² represents a glycidyl group. ]

［式（４）中、Ｒ^１３は水素原子又はメチル基を示し、Ｙ^３は水素原子又はグリシジル基を示す。なお、２つのＲ^１３は同一でも異なっていてもよく、２つのＹ^３は同一でも異なっていてもよい。但し、Ｙ^３の少なくとも一方はグリシジル基を示す。］

＜２＞（Ｂ）エチレン性不飽和結合を有する光重合性モノマーが、エチレン性不飽和結合を１分子内に３つ以上有する多官能光重合性モノマーである＜１＞に記載の感光性樹脂組成物。
＜３＞更に（Ｅ）顔料を含む＜１＞又は＜２＞に記載の感光性樹脂組成物。

[In the formula (4), R ¹³ represents a hydrogen atom or a methyl group, and Y ³ represents a hydrogen atom or a glycidyl group. Two R ¹³ may be the same or different, and two Y ³ may be the same or different. However, at least one of Y ³ represents a glycidyl group. ]

<2> (B) The photosensitive resin according to <1>, wherein the photopolymerizable monomer having an ethylenically unsaturated bond is a polyfunctional photopolymerizable monomer having three or more ethylenically unsaturated bonds in one molecule. Composition.
<3> The photosensitive resin composition according to <1> or <2>, further comprising (E) a pigment.

  ADVANTAGE OF THE INVENTION According to this invention, the photosensitive resin composition for protective films of the printed wiring board which can make high heat resistance, a low thermal expansion coefficient, and electrical reliability compatible, without reducing resolution can be provided.

Hereinafter, preferred embodiments of the present invention will be described in detail.
First, the photosensitive resin composition which concerns on suitable embodiment is demonstrated. The (A) acid-modified vinyl group-containing epoxy resin used in the present invention will be described. As the (A) acid-modified vinyl group-containing epoxy resin of the present invention, a novolac type epoxy resin represented by the above general formula (2) from the viewpoint of being capable of alkali development and having excellent resolution and adhesiveness; Resin obtained by reacting epoxy resin (a) mixed with bisphenol type novolak resin having a structural unit represented by the above general formula (3) or (4) and vinyl group-containing monocarboxylic acid (b) And a resin (A ′) obtained by reacting a saturated or unsaturated group-containing polybasic acid anhydride. In (a), the content of the novolak type epoxy resin represented by the general formula (2) is preferably 10 to 40% by mass, more preferably 15 to 35% by mass, based on the total amount of the component (A), and 20 to 30%. More preferred is mass%.

  In the photosensitive resin composition, the content of the component (A) is preferably 5 to 60% by mass and more preferably 10 to 50% by mass based on the total solid content of the photosensitive resin composition. Preferably, it is 15-40 mass%. When the content of the component (A) is within the above range, a coating film that is superior in heat resistance, electrical characteristics, and chemical resistance can be obtained.

  (B) As a compound which has an ethylenically unsaturated bond, the compound whose molecular weight is 1000 or less is preferable, for example, hydroxyalkyl (meth), such as 2-hydroxyethyl (meth) acrylate and 2-hydroxypropyl (meth) acrylate. (Meth) acrylamides such as acrylates, glycol mono- or di (meth) acrylates such as ethylene glycol, methoxytetraethylene glycol, polyethylene glycol, N, N-dimethyl (meth) acrylamide, N-methylol (meth) acrylamide Aminoalkyl (meth) acrylates such as N, N-dimethylaminoethyl (meth) acrylate, hexanediol, trimethylolpropane, pentaerythritol, ditrimethylolpropane, dipentaerythritol Of polyhydric alcohols such as tris-hydroxyethyl isocyanurate, or polyhydric (meth) acrylates of these ethylene oxide or propylene oxide adducts, phenoxyethyl (meth) acrylate, and phenols such as polyethoxydi (meth) acrylate of bisphenol A (Meth) acrylates of ethylene oxide or propylene oxide adducts, (meth) acrylates of glycidyl ethers such as glycerin diglycidyl ether, trimethylolpropane triglycidyl ether, triglycidyl isocyanurate, and melamine (meth) acrylate, acrylamide, Examples include acrylonitrile, diacetone acrylamide, styrene, vinyl toluene, and the like. These (B) compounds having an ethylenically unsaturated group are used singly or in combination of two or more. In addition, it is more preferable to have three or more ethylenic bonds in one molecule in order to increase the crosslinking density by photocuring and improve heat resistance and electrical reliability. Examples of the compound having such an ethylenically unsaturated bond include dipentaerythritol triacrylate.

(C) As the photopolymerization initiator, for example, benzoins such as benzoin, benzoin methyl ether, benzoin isopropyl ether; acetophenone, 2,2-dimethoxy-2-phenylacetophenone, 2,2-diethoxy-2-phenylacetophenone, 1,1-dichloroacetophenone, 1-hydroxycyclohexyl phenyl ketone, 2-benzyl-2-dimethylamino-1- (4-morpholinophenyl) -butanone-1,2-methyl-1- [4- (methylthio) phenyl] Acetophenones such as 2-morpholino-1-propanone and N, N-dimethylaminoacetophenone; 2-methylanthraquinone, 2-ethylanthraquinone, 2-tert-butylanthraquinone, 1-chloroanthraquinone, 2-amylanthraquino Anthraquinones such as 2-aminoanthraquinone; thioxanthones such as 2,4-dimethylthioxanthone, 2,4-diethylthioxanthone, 2-chlorothioxanthone and 2,4-diisopropylthioxanthone; ketals such as acetophenone dimethyl ketal and benzyldimethyl ketal Benzophenones such as benzophenone, methylbenzophenone, 4,4′-dichlorobenzophenone, 4,4′-bis (diethylamino) benzophenone, Michler's ketone, 4-benzoyl-4′-methyldiphenyl sulfide; 2- (o-chlorophenyl) -4,5-diphenylimidazole dimer, 2- (o-chlorophenyl) -4,5-di (m-methoxyphenyl) imidazole dimer, 2- (o-fluorophenyl) -4,5-di Phenylimidazole dimer, 2- (o-methoxyphenyl) -4,5-diphenylimidazole dimer, 2- (p-methoxyphenyl) -4,5-diphenylimidazole dimer, 2,4-di ( 2,4,5-triarylimidazole dimers such as p-methoxyphenyl) -5-phenylimidazole dimer, 2- (2,4-dimethoxyphenyl) -4,5-diphenylimidazole dimer, Acridines such as 9-phenylacridine, 1,7-bis (9,9'-acridinyl) heptane; acylphosphine oxides such as 2,4,6-trimethylbenzoyldiphenylphosphine oxide, 1,2-octanedione- 1- [4- (phenylthio) phenyl] -2- (O-benzoyloxime), 1- [9-ethyl-6- (2-methyl) Nzoyl) -9H-carbazol-3-yl] ethanone 1- (O-acetyloxime), 1-phenyl-1,2-propanedione-2- [O- (ethoxycarbonyl) oxime] and other oxime esters It is done. These (C) photoinitiators can be used individually by 1 type or in combination of 2 or more types. More specifically, BASF Japan Co., Ltd., which has good curability at the bottom for photobleaching, trade name: Irgacure 819 (bis (2,4,6-trimethylbenzoyl) phenylphosphine oxide, “Irgacure” is a registered trademark ), Or a product name: Irgacure 369 (2-benzyl-2-dimethylamino-1- (4-morpholinophenyl) -butanone-1) manufactured by BASF Japan Ltd., which is less likely to be generated as outgas due to being less volatile.

  Further, (C) light such as tertiary amines such as N, N-dimethylaminobenzoic acid ethyl ester, N, N-dimethylaminobenzoic acid isoamyl ester, pentyl-4-dimethylaminobenzoate, triethylamine, triethanolamine and the like. The polymerization initiation assistants can be used alone or in combination of two or more.

(D) The inorganic filler will be described below. (D) As an inorganic filler, for example, silica (SiO ₂ ), alumina (Al ₂ O ₃ ), titania (TiO ₂ ), tantalum oxide (Ta ₂ O ₅ ), zirconia (ZrO ₂ ), silicon nitride (Si ₃₎ N ₄ ), barium titanate (BaO · TiO ₂ ), barium carbonate (BaCO ₃ ), magnesium carbonate, aluminum hydroxide, magnesium hydroxide, lead titanate (PbO · TiO ₂ ), lead zirconate titanate (PZT) , lead lanthanum zirconate titanate (PLZT), gallium oxide _{(Ga 2 O} 3), spinel _{(MgO · Al 2 O 3)} , mullite _{(3Al 2 O 3 · 2SiO 2} ), cordierite (2MgO · _2Al 2 O ₃ / 5SiO _2), talc _{(3MgO · 4SiO 2 · H 2} O), aluminum titanate (TiO ₂ Al ₂ O _3), yttria-containing zirconia _{(Y 2 O 3 -ZrO 2)} , barium silicate (BaO · 8SiO _2), boron nitride (BN), calcium carbonate (CaCO _3), barium sulfate (BaSO _4), sulfuric acid Calcium (CaSO ₄ ), zinc oxide (ZnO), magnesium titanate (MgO · TiO ₂ ), hydrotalcite, mica, calcined kaolin, carbon (C) and the like can be used. These (D) inorganic fillers can be used singly or in combination of two or more.

  The inorganic filler (D) used in the present invention preferably uses a silane coupling agent in order to disperse it in the resin without agglomeration with the primary particle size. As the silane coupling agent, generally available ones can be used, for example, alkyl silane, alkoxy silane, vinyl silane, epoxy silane, amino silane, acrylic silane, methacryl silane, mercapto silane, sulfide silane, isocyanate silane, Sulfur silane, styryl silane, alkylchlorosilane, and the like can be used. Specific compound names include methyltrimethoxysilane, dimethyldimethoxysilane, trimethylmethoxysilane, methyltriethoxysilane, methyltriphenoxysilane, ethyltrimethoxysilane, n-propyltrimethoxysilane, diisopropyldimethoxysilane, isobutyltrimethoxy. Silane, diisobutyldimethoxysilane, isobutyltriethoxysilane, n-hexyltrimethoxysilane, n-hexyltriethoxysilane, cyclohexylmethyldimethoxysilane, n-octyltriethoxysilane, n-dodecylmethoxysilane, phenyltrimethoxysilane, diphenyldimethoxy Silane, triphenylsilanol, methyltrichlorosilane, dimethyldichlorosilane, trimethylchlorosilane, n-octyldi Tylchlorosilane, tetraethoxysilane, 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, 3- (2-aminoethyl) aminopropyltrimethoxysilane, 3- (2-aminoethyl) aminopropylmethyldimethoxysilane , 3-phenylaminopropyltrimethoxysilane, 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropylmethyldimethoxysilane, 3-glycidoxypropyltriethoxysilane, 3-glycidoxypropylmethyldiethoxysilane Bis (3- (triethoxysilyl) propyl) disulfide, bis (3- (triethoxysilyl) propyl) tetrasulfide, vinyltriacetoxysilane, vinyltrimethoxysilane, vinyltriethoxysilane, Lutriisopropoxysilane, allyltrimethoxysilane, diallyldimethylsilane, 3-methacryloxypropyltrimethoxysilane, 3-methacryloxypropylmethyldimethoxysilane, 3-methacryloxypropyltriethoxysilane, 3-mercaptopropyltrimethoxysilane, 3 -Mercaptopropylmethyldimethoxysilane, 3-mercaptopropyltriethoxysilane, N- (1,3-dimethylbutylidene) -3-aminopropyltriethoxysilane, aminosilane, monomethyltriisocyanatesilane, tetraisocyanatesilane, γ-isocyanatopropyl A triethoxysilane is mentioned. As the silane coupling agent to be used, those that react with the carboxy group of the (A) acid-modified vinyl group-containing epoxy resin contained in the photosensitive resin composition are preferable. For example, epoxy silane, acrylic silane, methacryl Silane is preferred. Since these silane coupling agents strengthen the bond between silica and resin, they increase the strength of the film when used as a permanent mask resist and contribute to crack resistance and the like in a temperature cycle test. Further, mercaptosilane or isocyanate silane may be used. (B) It is thought that it reacts with the ethylenically unsaturated group of the photopolymerizable monomer having an ethylenically unsaturated bond and exhibits the same effect as when the silane coupling agent is used.

  In the photosensitive resin composition, the content of the component (D) is preferably 20 to 60% by mass based on the total solid content of the photosensitive resin composition from the viewpoint of resolution and low thermal expansion coefficient. More preferably, it is 30-55 mass%, and it is still more preferable that it is 35-50 mass%. When the content of the component (D) is within the above range, the low thermal expansion coefficient, heat resistance, insulation reliability, thermal shock resistance, resolution, film strength and the like can be further improved. When the filling amount exceeds 60% by mass, it is difficult to disperse in the resin, and the flowability of the photosensitive resin composition tends to decrease. If the filling amount is less than 5% by mass, it tends to be difficult to obtain crack resistance during reflow mounting.

  (D) The average particle diameter of the inorganic filler is preferably 0.01 to 1 μm, more preferably 0.1 to 1 μm from the viewpoints of practicality and resolution, and 0.3 to 0.7 μm. More preferably it is. Further, (D) the inorganic filler preferably has a maximum particle size of 0.1 to 5 μm, more preferably 0.1 to 3 μm, and further preferably 0.1 to 1 μm. If the maximum particle diameter exceeds 5 μm, resolution and insulation reliability tend to be impaired.

  Among the inorganic fillers (D), it is preferable to use silica fine particles from the viewpoint of improving the low expansion coefficient and heat resistance. From the viewpoint of improving the adhesive strength between the underfill material and the cured film after solder heat resistance, HAST resistance (insulation reliability), crack resistance (thermal shock resistance), and PCT (Pressure Cooker Test) resistance test. It is also preferable to use barium sulfate fine particles. Moreover, it is preferable that the said silica fine particle is surface-treated with an alumina and / or an organosilane type compound from a viewpoint which can improve the aggregation prevention effect.

  The content in the case of using the silica is preferably 25 to 60% by mass, more preferably 30 to 55% by mass, and more preferably 35 to 50% by mass based on the total solid content of the photosensitive resin composition. More preferably. When the content of the silica fine particles is within the above range, the low expansion coefficient, solder heat resistance, and the adhesive strength between the underfill material and the cured film after the PCT resistance test can be further improved.

  The photosensitive resin composition of the present invention preferably contains (E) a pigment in order to improve the identification and appearance of the production apparatus.

  The photosensitive resin composition of the present invention preferably further contains (F) a curing agent. (F) By containing a hardening | curing agent, the heat resistance of the cured film formed from the photosensitive resin composition, adhesiveness with an underfill material, chemical resistance, etc. can be improved more.

  Moreover, it is preferable that the photosensitive resin composition of this invention further contains (G) elastomer. (G) By containing an elastomer, the flexibility of the cured film formed from the photosensitive resin composition, the adhesiveness with the underfill material, and the like can be further improved.

  The resin (A ′) is presumed to have a hydroxyl group formed by an addition reaction between the epoxy group of the epoxy resin (a) and the carboxyl group of the vinyl group-containing monocarboxylic acid (b).

  The epoxy resin (a) is preferably a novolac type epoxy resin represented by the general formula (2) from the viewpoint of excellent process tolerance and improved solvent resistance.

  Examples of the novolak type epoxy resin represented by the general formula (2) include a phenol novolak type epoxy resin and a cresol novolak type epoxy resin. These novolak-type epoxy resins can be obtained, for example, by reacting a phenol novolak resin, a cresol novolak resin and epichlorohydrin by a known method.

  Examples of the phenol novolak type epoxy resin or cresol novolak type epoxy resin represented by the general formula (2) include YDCN-701, YDCN-702, YDCN-703, YDCN-704, YDCN-704L, YDPN-638, and YDPN- 602 (above, trade name, manufactured by Nippon Kayaku Epoxy Manufacturing Co., Ltd.), DEN-431, DEN-439 (above, trade name, manufactured by Dow Chemical Co., Ltd.), EOCN-120, EOCN-102S, EOCN-103S, EOCN -104S, EOCN-1012, EOCN-1025, EOCN-1027, BREN (above, Nippon Kayaku Co., Ltd., trade names ("EOCN", "BREN" are registered trademarks)), EPN-1138, EPN-1235, EPN-1299 (above, manufactured by BASF Japan Ltd., Name), N-730, N-770, N-865, N-665, N-673, VH-4150, VH-4240 (manufactured by DIC Corporation, trade name) is commercially available.

  In order to promote the reaction between the hydroxyl group and epichlorohydrin, the reaction is preferably carried out in a polar organic solvent such as dimethylformamide, dimethylacetamide, dimethylsulfoxide in the presence of an alkali metal hydroxide at a reaction temperature of 50 to 120 ° C. When the reaction temperature is less than 50 ° C., the reaction is slow, and when the reaction temperature is 120 ° C., there are many side reactions.

  The epoxy resin (a) is a structural unit represented by the general formula (3) and / or the general formula (4) from the viewpoint that the warpage of the thin film substrate can be further reduced and the thermal shock resistance can be further improved. It is preferable to use an epoxy resin having

In the general formula (4), when R ¹³ is a hydrogen atom and Y ³ is a glycidyl group, EXA-7376 series (trade name, manufactured by DIC Corporation), and R ¹³ is a methyl group, Y ³ having a glycidyl group is commercially available as the EPON SU8 series (trade name, manufactured by Mitsubishi Chemical Corporation).

  Examples of the vinyl group-containing monocarboxylic acid (b) include acrylic acid, dimer of acrylic acid, methacrylic acid, β-furfurylacrylic acid, β-styrylacrylic acid, cinnamic acid, crotonic acid, α- Acrylic acid derivatives such as cyanocinnamic acid, half-ester compounds which are reaction products of hydroxyl group-containing acrylates and dibasic acid anhydrides, vinyl group-containing monoglycidyl ethers or vinyl group-containing monoglycidyl esters and dibasic acid anhydrides The half-ester compound which is a reaction product of is mentioned.

  The half ester compound is obtained by reacting a hydroxyl group-containing acrylate, a vinyl group-containing monoglycidyl ether or a vinyl group-containing monoglycidyl ester with a dibasic acid anhydride in an equimolar ratio. These vinyl group-containing monocarboxylic acids (b) can be used singly or in combination of two or more.

  Examples of the hydroxyl group-containing acrylate, vinyl group-containing monoglycidyl ether, and vinyl group-containing monoglycidyl ester used in the synthesis of the half ester compound as an example of the vinyl group-containing monocarboxylic acid (b) include hydroxyethyl acrylate, hydroxyethyl Methacrylate, hydroxypropyl acrylate, hydroxypropyl methacrylate, hydroxybutyl acrylate, hydroxybutyl methacrylate, polyethylene glycol monoacrylate, polyethylene glycol monomethacrylate, trimethylolpropane diacrylate, trimethylolpropane dimethacrylate, pentaerythritol triacrylate, pentaerythritol tris Methacrylate, dipentaerythritol pentaacrylate, Data dipentaerythritol methacrylate, glycidyl acrylate, glycidyl methacrylate.

  As a dibasic acid anhydride used for the synthesis | combination of the said half ester compound, what contains a saturated group and what contains an unsaturated group can be used. Specific examples of dibasic acid anhydrides include succinic anhydride, maleic anhydride, tetrahydrophthalic anhydride, phthalic anhydride, methyltetrahydrophthalic anhydride, ethyltetrahydrophthalic anhydride, hexahydrophthalic anhydride, methylhexahydrophthalic anhydride. Examples include acid, ethylhexahydrophthalic anhydride, itaconic anhydride and the like.

  In the reaction of the epoxy resin (a) and the vinyl group-containing monocarboxylic acid (b), the vinyl group-containing monocarboxylic acid (b) is 0.6 to 1 with respect to 1 equivalent of the epoxy group of the epoxy resin (a). It is preferable to make it react by the ratio used as 1.05 equivalent, and it is more preferable to make it react by the ratio used as 0.8-1.0 equivalent.

  The epoxy resin (a) and the vinyl group-containing monocarboxylic acid (b) can be reacted by dissolving in an organic solvent. Examples of the organic solvent include ketones such as ethyl methyl ketone and cyclohexanone; aromatic hydrocarbons such as toluene, xylene and tetramethylbenzene; methyl cellosolve, butyl cellosolve, methyl carbitol, butyl carbitol, propylene glycol monomethyl ether, Glycol ethers such as dipropylene glycol monoethyl ether, dipropylene glycol diethyl ether and triethylene glycol monoethyl ether; esters such as ethyl acetate, butyl acetate, butyl cellosolve acetate and carbitol acetate; aliphatic carbonization such as octane and decane Hydrogen: petroleum-based solvents such as petroleum ether, petroleum naphtha, hydrogenated petroleum naphtha, and solvent naphtha.

  Furthermore, it is preferable to use a catalyst to promote the reaction. Examples of the catalyst that can be used include triethylamine, benzylmethylamine, methyltriethylammonium chloride, benzyltrimethylammonium chloride, benzyltrimethylammonium bromide, benzyltrimethylmethylammonium iodide, and triphenylphosphine. The amount of the catalyst used is preferably 0.1 to 10 parts by mass with respect to 100 parts by mass in total of the epoxy resin (a) and the vinyl group-containing monocarboxylic acid (b).

  Moreover, it is preferable to use a polymerization inhibitor for the purpose of preventing polymerization during the reaction. Examples of the polymerization inhibitor include hydroquinone, methyl hydroquinone, hydroquinone monomethyl ether, catechol, and pyrogallol. The amount of the polymerization inhibitor used is preferably 0.01 to 1 part by mass with respect to 100 parts by mass in total of the epoxy resin (a) and the vinyl group-containing monocarboxylic acid (b). Moreover, reaction temperature becomes like this. Preferably it is 60-150 degreeC, More preferably, it is 80-120 degreeC.

  Further, if necessary, a vinyl group-containing monocarboxylic acid (b) and a phenolic compound such as p-hydroxyphenethyl alcohol, trimellitic anhydride, pyromellitic anhydride, benzophenonetetracarboxylic anhydride, biphenyltetracarboxylic acid A polybasic acid anhydride such as an anhydride can be used in combination.

  In the present invention, (A) the acid-modified vinyl group-containing epoxy resin is a resin (A ″) obtained by reacting the above-mentioned resin (A ′) with a polybasic acid anhydride (c). Is also preferable.

  In the resin (A ″), the hydroxyl group in the resin (A ′) (including the original hydroxyl group in the epoxy resin (a)) and the acid anhydride group of the polybasic acid anhydride (c) are half-esterified. It is presumed that

  As the polybasic acid anhydride (c), one containing a saturated group or one containing an unsaturated group can be used. Specific examples of the polybasic acid anhydride (c) include succinic anhydride, maleic anhydride, tetrahydrophthalic anhydride, phthalic anhydride, methyltetrahydrophthalic anhydride, ethyltetrahydrophthalic anhydride, hexahydrophthalic anhydride, methylhexa Examples include hydrophthalic anhydride, ethylhexahydrophthalic anhydride, and itaconic anhydride.

  In the reaction of the resin (A ′) and the polybasic acid anhydride (c), the polybasic acid anhydride (c) is 0.1 to 1.0 equivalent per 1 equivalent of the hydroxyl group in the resin (A ′). By reacting, the acid value of the acid-modified vinyl group-containing epoxy resin can be adjusted.

  (A) The acid value of the acid-modified vinyl group-containing epoxy resin is preferably 30 to 150 mgKOH / g, more preferably 40 to 120 mgKOH / g, and still more preferably 50 to 100 mgKOH / g. If the acid value is less than 30 mg KOH / g, the solubility of the photosensitive resin composition in a dilute alkaline solution tends to be reduced, and if it exceeds 150 mg KOH / g, the electric properties of the cured film tend to be reduced.

  The reaction temperature between the resin (A ′) and the polybasic acid anhydride (c) is preferably 60 to 120 ° C.

  Moreover, as needed, as a epoxy resin (a), hydrogenated bisphenol A type epoxy resin can also be used together partially, for example. Further, (A) acid-modified vinyl group-containing epoxy resin, styrene-maleic acid series such as hydroxyethyl acrylate modified product of styrene-maleic anhydride copolymer or hydroxyethyl acrylate modified product of styrene-maleic anhydride copolymer A part of the resin may be used in combination.

  In the present invention, (meth) acrylic acid means acrylic acid and methacrylic acid corresponding thereto, (meth) acrylate means acrylate and corresponding methacrylate, (meth) acryloyl group means acryloyl group and The methacryloyl group corresponding to it means a (meth) acryloxy group means an acryloxy group and a methacryloxy group corresponding to it.

  The photosensitive resin composition of the present invention may further contain (E) a pigment, (F) a curing agent, and / or (G) an elastomer in addition to the components (A) to (D) described above. Further, (H) an epoxy resin curing agent may be included. Hereinafter, each component will be described.

<(F) Curing agent>
(F) The curing agent is preferably a compound that cures itself by heat, ultraviolet rays or the like, or (A) a compound that cures by reacting with carboxyl groups, hydroxyl groups, heat, ultraviolet rays, etc. of the acid-modified vinyl group-containing epoxy resin. . (F) By using a hardening | curing agent, the heat resistance of the cured film formed from a photosensitive resin composition, adhesiveness, chemical resistance, etc. can be improved.

  (F) As a hardening | curing agent, thermosetting compounds, such as an epoxy compound, a melamine compound, a urea compound, an oxazoline compound, block type isocyanate, are mentioned, for example. Examples of the epoxy compound include bisphenol A type epoxy resin, bisphenol F type epoxy resin, hydrogenated bisphenol A type epoxy resin, brominated bisphenol A type epoxy resin, novolac type epoxy resin, bisphenol S type epoxy resin, and biphenyl type epoxy resin. , Naphthalene type epoxy resins, dicyclo type epoxy resins, hydantoin type epoxy resins, heterocyclic epoxy resins such as triglycidyl isocyanurate, and bixylenol type epoxy resins. Examples of the melamine compound include triaminotriazine, hexamethoxymelamine, and hexabutoxylated melamine. Examples of the urea compound include dimethylol urea.

  (F) It is preferable that a hardening | curing agent contains an epoxy compound (epoxy resin) and / or block type isocyanate from a viewpoint which can improve the heat resistance of a cured film more, and an epoxy compound and block type isocyanate are included. It is more preferable to use together.

  As the block type isocyanate, an addition reaction product of a polyisocyanate compound and an isocyanate blocking agent is used. Examples of the polyisocyanate compound include tolylene diisocyanate, xylylene diisocyanate, phenylene diisocyanate, naphthylene diisocyanate, bis (isocyanate methyl) cyclohexane, tetramethylene diisocyanate, hexamethylene diisocyanate, methylene diisocyanate, trimethylhexamethylene diisocyanate, and isophorone diisocyanate. Polyisocyanate compounds, and adducts, burettes and isocyanurates of these.

  Examples of the isocyanate blocking agent include phenolic blocking agents such as phenol, cresol, xylenol, chlorophenol and ethylphenol; lactam blocking agents such as ε-caprolactam, δ-palerolactam, γ-butyrolactam and β-propiolactam; Active methylene blocking agents such as ethyl acetoacetate and acetylacetone; methanol, ethanol, propanol, butanol, amyl alcohol, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monobutyl ether, diethylene glycol monomethyl ether, propylene glycol monomethyl ether, benzyl Ether, methyl glycolate, butyl glycolate, diacetone alcohol, lactic acid And alcohol blocking agents such as ethyl lactate; oxime blocking agents such as formaldehyde oxime, acetaldoxime, acetoxime, methylethyl ketoxime, diacetyl monooxime, cyclohexane oxime; butyl mercaptan, hexyl mercaptan, t-butyl mercaptan, thiophenol, Mercaptan block agents such as methylthiophenol and ethylthiophenol; Acid amide block agents such as acetic acid amide and benzamide; Imide block agents such as succinimide and maleic imide; Amines such as xylidine, aniline, butylamine and dibutylamine Blocking agents; imidazole blocking agents such as imidazole and 2-ethylimidazole; imine blocking agents such as methyleneimine and propyleneimine The

  (F) A hardening | curing agent is used individually by 1 type or in combination of 2 or more types. (F) When using a hardening | curing agent, it is preferable that the content is 2-40 mass% on the basis of the solid content whole quantity of the photosensitive resin composition, and it is more preferable that it is 3-30 mass%. More preferably, it is 5-20 mass%. (F) By making content of a hardening | curing agent into the range of 2-40 mass%, the heat resistance of the cured film formed can be improved more, maintaining favorable developability.

<(G) Elastomer>
(G) The elastomer can be suitably used when the photosensitive resin composition of the present invention is used for a semiconductor package substrate. By adding the (G) elastomer to the photosensitive resin composition of the present invention, the crosslinking reaction (curing reaction) proceeds by ultraviolet rays or heat, so that the (A) acid-modified vinyl group-containing epoxy resin is cured and contracted. Further, the problem that distortion (internal stress) is applied to the inside of the resin and flexibility and adhesiveness are lowered can be solved.

  Examples of (G) elastomers include styrene elastomers, olefin elastomers, urethane elastomers, polyester elastomers, polyamide elastomers, acrylic elastomers, and silicone elastomers. These (G) elastomers are composed of a hard segment component and a soft segment component. In general, the former contributes to heat resistance and strength, and the latter contributes to flexibility and toughness.

  Examples of the styrenic elastomer include styrene-butadiene-styrene block copolymer, styrene-isoprene-styrene block copolymer, styrene-ethylene-butylene-styrene block copolymer, styrene-ethylene-propylene-styrene block copolymer, and the like.

  As a component constituting the styrene-based elastomer, styrene derivatives such as α-methylstyrene, 3-methylstyrene, 4-propylstyrene, and 4-cyclohexylstyrene can be used in addition to styrene. More specifically, Tufprene, Solprene T, Asaprene T, Tuftec (trade name (“Tufprene”, “Sorprene”, “Asaprene”, “Tuftec” are registered trademarks)) manufactured by Asahi Kasei Chemicals Corporation, elastomer AR (Aron Kasei Co., Ltd., trade name), Clayton G, Califlex (Craton Polymers, trade name (“Clayton”, “Califlex” are registered trademarks)), JSR-TR, TSR-SIS, Dynalon (The above is made by JSR Corporation, trade names (“JSR”, “JSR SIS”, “Dynaron” are registered trademarks)), Denka STR (made by Denki Kagaku Kogyo Co., Ltd., trade names (“Denka” is a registered trademark)) , Quintac (manufactured by ZEON CORPORATION, trade name ("Quintac" is a registered trademark)), TPE-SB series Chemical Co., Ltd., Lavalon (Mitsubishi Chemical Co., Ltd., trade name ("Lavalon" is a registered trademark)), Septon, Hibler (above, Kuraray Co., Ltd., trade names ("Septon", "Hibler" are registered trademarks) )), Sumiflex (manufactured by Sumitomo Bakelite Co., Ltd., trade name ("Sumiflex" is a registered trademark)), Reostomer, Actimer (above, made by Riken Technos Co., Ltd., trade name ("Reostomer", "Actimar" are registered) Trademark)) and the like.

  The olefin-based elastomer is a copolymer of an α-olefin having 2 to 20 carbon atoms such as ethylene, propylene, 1-butene, 1-hexene and 4-methyl-pentene. Specific examples thereof include ethylene-propylene copolymer (EPR), ethylene-propylene-diene copolymer (EPDM), dicyclopentadiene, 1,4-hexadiene, cyclooctadiene, methylene norbornene, ethylidene norbornene, butadiene, Examples thereof include carboxy-modified NBR in which methacrylic acid is copolymerized with a non-conjugated diene having 2 to 20 carbon atoms such as isoprene, an α-olefin copolymer, and a butadiene-acrylonitrile copolymer. More specifically, ethylene / α-olefin copolymer rubber, ethylene / α-olefin / non-conjugated diene copolymer rubber, propylene / α-olefin copolymer rubber, butene / α-olefin copolymer rubber Can be mentioned. More specifically, Miralastomer (made by Mitsui Chemicals, Inc., trade name (“Miralastomer” is a registered trademark)), EXACT (produced by ExxonMobil Co., Ltd., trade name (“EXACT” is a registered trademark)), ENGAGE (Dow)・ Chemical, product name (“ENGAGE” is a registered trademark), hydrogenated styrene-butadiene rubber “DYNARON HSBR” (manufactured by JSR Corporation, product name (“DYNARON” is a registered trademark)), butadiene-acrylonitrile copolymer Combined “NBR series” (trade name, manufactured by JSR Corporation), or “XER series” of both end carboxyl group-modified butadiene-acrylonitrile copolymers (trade name (“XER” is a registered trademark) manufactured by JSR Corporation), BF-100 of epoxidized polybudadiene partially epoxidized with polybutadiene (Manufactured by Nippon Soda Co., Ltd., trade name), PB-3600 (Corporation Daicel Ltd., trade name), or the like can be used.

  Urethane elastomers are composed of structural units consisting of a hard segment composed of low molecular weight glycol and diisocyanate and a soft segment composed of a high molecular (long chain) diol and diisocyanate.

  As the low-molecular glycol, for example, short chain diols such as ethylene glycol, propylene glycol, 1,4-butanediol, and bisphenol A can be used. The number average molecular weight of the short chain diol is preferably 48 to 500.

  Examples of the polymer (long chain) diol include polypropylene glycol, polytetramethylene oxide, poly (1,4-butylene adipate), poly (ethylene / 1,4-butylene adipate), polycaprolactone, and poly (1,6 -Hexylene carbonate) and poly (1,6-hexylene neopentylene adipate). The number average molecular weight of the polymer (long chain) diol is preferably 500 to 10,000.

  Specific examples of the urethane-based elastomer include PANDEX T-2185, T-2983N (manufactured by DIC Corporation, trade name (“PANDEX” is a registered trademark)), Miractolan E790 (manufactured by Nippon Milactolan Co., Ltd., trade name (“Milactolan”) Is a registered trademark)).

  Examples of the polyester elastomer include those obtained by polycondensation of a dicarboxylic acid or a derivative thereof and a diol compound or a derivative thereof.

  Specific examples of the dicarboxylic acid include aromatic dicarboxylic acids such as terephthalic acid, isophthalic acid, and naphthalenedicarboxylic acid, and aromatic dicarboxylic acids in which hydrogen atoms of these aromatic nuclei are substituted with methyl groups, ethyl groups, phenyl groups, and the like, Examples thereof include aliphatic dicarboxylic acids having 2 to 20 carbon atoms such as adipic acid, sebacic acid and dodecanedicarboxylic acid, and alicyclic dicarboxylic acids such as cyclohexanedicarboxylic acid. These compounds can be used individually by 1 type or in combination of 2 or more types.

  Specific examples of the diol compound include aliphatic diols such as ethylene glycol, 1,3-propanediol, 1,4-butanediol, 1,6-hexanediol, 1,10-decanediol, and 1,4-cyclohexanediol. And a dihydric phenol represented by the following general formula (5).

［式中、Ｙ^１１は炭素数１〜１０のアルキレン基、炭素数４〜８のシクロアルキレン基、−Ｏ−、−Ｓ−、又は、−ＳＯ_２−を示し、Ｒ^２１及びＲ^２２はハロゲン原子又は炭素数１〜１２のアルキル基を示し、ｐ及びｑは０〜４の整数を示し、ｒは０又は１を示す。］

[Wherein Y ¹¹ represents an alkylene group having 1 to 10 carbon atoms, a cycloalkylene group having 4 to 8 carbon atoms, —O—, —S—, or —SO ₂ —, and R ²¹ and R ²² represent halogen atoms. An atom or a C1-C12 alkyl group is shown, p and q show the integer of 0-4, r shows 0 or 1. ]

  Specific examples of the dihydric phenol represented by the general formula (5) include bisphenol A, bis- (4-hydroxyphenyl) methane, bis- (4-hydroxy-3-methylphenyl) propane, and resorcin. These compounds can be used individually by 1 type or in combination of 2 or more types.

  In addition, a multiblock copolymer having an aromatic polyester (for example, polybutylene terephthalate) portion as a hard segment component and an aliphatic polyester (for example, polytetramethylene glycol) portion as a soft segment component can be used. There are various grades depending on the type, ratio, and molecular weight of the hard and soft segments. Specific examples include Hytrel (manufactured by Toray DuPont Co., Ltd., trade name (“Hytrel” is a registered trademark)), Perprene (manufactured by Toyobo Co., Ltd., trade name (“Pelprene” is a registered trademark)), Espel (Hitachi Chemical Industries, Ltd.) Product name (“Esper” is a registered trademark)) and the like.

  Polyamide elastomers are broadly classified into two types: polyether block amide type and polyether ester block amide type using polyamide for the hard segment and polyether or polyester for the soft segment.

  As the polyamide, polyamide-6, 11, 12 or the like is used. As the polyether, polyoxyethylene, polyoxypropylene, polytetramethylene glycol or the like is used. Specifically, UBE polyamide elastomer (manufactured by Ube Industries, trade name ("UBE" is a registered trademark)), Daiamide (manufactured by Daicel Evonik, trade name ("Daiamide" is a registered trademark)), PEBAX ( Arkema, product name ("PEBAX" is a registered trademark), Grilon ELY (Ms Chemie Japan, product name ("Grillon" is a registered trademark)), Novamid (DSM, product name ("Novamid") Is a registered trademark)), and Glais (Toyobo Co., Ltd.) can be used.

  The acrylic elastomer is mainly composed of acrylic acid ester, and ethyl acrylate, butyl acrylate, methoxyethyl acrylate, ethoxyethyl acrylate, or the like is used. Moreover, glycidyl methacrylate, allyl glycidyl ether, etc. are used as a crosslinking point monomer. Furthermore, acrylonitrile and ethylene can be copolymerized. Specifically, an acrylonitrile-butyl acrylate copolymer, an acrylonitrile-butyl acrylate-ethyl acrylate copolymer, an acrylonitrile-butyl acrylate-glycidyl methacrylate copolymer, or the like can be used.

  Silicone elastomers are mainly composed of organopolysiloxane, and are classified into polydimethylsiloxane, polymethylphenylsiloxane, and polydiphenylsiloxane. Some are modified with vinyl groups, alkoxy groups, and the like. Specific examples include KE series (manufactured by Shin-Etsu Chemical Co., Ltd., trade name), SE series, CY series, SH series (above, trade name by Toray Dow Corning Co., Ltd.).

  In addition to the above-described elastomer, a rubber-modified epoxy resin can also be used. The rubber-modified epoxy resin includes, for example, a part or all of the epoxy groups of the bisphenol F type epoxy resin, bisphenol A type epoxy resin, salicylaldehyde type epoxy resin, phenol novolac type epoxy resin or cresol novolac type epoxy resin. It is obtained by modifying with a terminal carboxylic acid-modified butadiene-acrylonitrile rubber, a terminal amino-modified silicone rubber or the like. Among these elastomers, both ends carboxyl group-modified butadiene-acrylonitrile copolymer and Espel (trade name: Espel 1612, 1620, manufactured by Hitachi Chemical Co., Ltd.) which is a polyester-based elastomer having a hydroxyl group in terms of shear adhesion. ), Epoxidized polybutadiene, etc. are preferred. An elastomer that is liquid at room temperature is particularly preferred.

  (G) When using an elastomer, the content is preferably 1 to 20% by mass, more preferably 2 to 15% by mass, based on the total solid content of the photosensitive resin composition. More preferably, it is 10 mass%. (G) By making the content of the elastomer in the range of 1 to 20% by mass, the thermal shock resistance and the adhesive strength between the underfill material and the cured film can be further improved while maintaining good developability. it can. Further, when used for a thin film substrate, warpage of the thin film substrate can be reduced.

  In the photosensitive resin composition of the present invention, (H) an epoxy resin curing agent can also be added for the purpose of further improving various properties such as heat resistance, adhesiveness and chemical resistance of the cured film to be formed. .

  Specific examples of such (H) epoxy resin curing agent include 2-methylimidazole, 2-ethyl-4-methylimidazole, 1-benzyl-2-methylimidazole, 2-phenylimidazole, 2-phenyl-4- Imidazole derivatives such as methyl-5-hydroxymethylimidazole; guanamines such as acetoguanamine and benzoguanamine; diaminodiphenylmethane, m-phenylenediamine, m-xylenediamine, diaminodiphenylsulfone, dicyandiamide, urea, urea derivatives, melamine, polybasic hydrazide These organic acid salts and / or epoxy adducts: amine complexes of boron trifluoride; ethyldiamino-S-triazine, 2,4-diamino-S-triazine, 2,4-diamino-6-xylyl -S- Triazine derivatives such as lyazine; trimethylamine, triethanolamine, N, N-dimethyloctylamine, N-benzyldimethylamine, pyridine, N-methylmorpholine, hexa (N-methyl) melamine, 2,4,6-tris ( Tertiary amines such as dimethylaminophenol), tetramethylguanidine, m-aminophenol; polyphenols such as polyvinylphenol, polyvinylphenol bromide, phenol novolac, alkylphenol novolac; tributylphosphine, triphenylphosphine, tris-2-cyanoethyl Organic phosphines such as phosphine; phosphonium salts such as tri-n-butyl (2,5-dihydroxyphenyl) phosphonium bromide and hexadecyltributylphosnium chloride Quaternary ammonium salts such as benzyltrimethylammonium chloride and phenyltributylammonium chloride; polybasic acid anhydrides as described above; diphenyliodonium tetrafluoroborate, triphenylsulfonium hexafluoroantimonate, 2,4,6-triphenylthiopyrylium hexa Fluorophosphate is mentioned. These (H) epoxy resin curing agents are used singly or in combination of two or more.

  (H) When using an epoxy resin hardening | curing agent, it is preferable that the content is 0.01-20 mass% on the basis of the solid content whole quantity of the photosensitive resin composition, and is 0.1-10 mass%. More preferably.

  Moreover, in order to further improve the flexibility of the cured film, (I) a thermoplastic resin can be added to the photosensitive resin composition of the present invention.

  (I) As a thermoplastic resin, an acrylic resin and a urethane resin are mentioned, for example. (I) When the thermoplastic resin is contained, the content is preferably 1 to 30% by mass, more preferably 5 to 20% by mass based on the total solid content of the photosensitive resin composition. .

  Furthermore, the photosensitive resin composition of the present invention includes, as necessary, organic fine particles such as melamine and organic bentonite, phthalocyanine blue, phthalocyanine green, iodine green, diazo yellow, crystal violet, titanium oxide, carbon black, naphthalene. Known colorants such as black, polymerization inhibitors such as hydroquinone, methylhydroquinone, hydroquinone monomethyl ether, catechol and pyrogallol, thickeners such as benton and montmorillonite, silicone-based, fluorine-based and vinyl resin-based antifoaming agents, silane Various commonly known additives such as coupling agents and diluents can be added. Furthermore, flame retardants such as brominated epoxy compounds, acid-modified brominated epoxy compounds, antimony compounds, phosphate compounds of phosphorus compounds, aromatic condensed phosphate esters, and halogen-containing condensed phosphate esters can also be added.

  As the diluent, for example, an organic solvent can be used. Examples of the organic solvent include ketones such as ethyl methyl ketone and cyclohexanone; aromatic hydrocarbons such as toluene, xylene and tetramethylbenzene; methyl cellosolve, butyl cellosolve, methyl carbitol, butyl carbitol, propylene glycol monomethyl ether, Glycol ethers such as dipropylene glycol monoethyl ether, dipropylene glycol diethyl ether and triethylene glycol monoethyl ether; esters such as ethyl acetate, butyl acetate, butyl cellosolve acetate and carbitol acetate; aliphatic carbonization such as octane and decane Hydrogen: petroleum-based solvents such as petroleum ether, petroleum naphtha, hydrogenated petroleum naphtha, and solvent naphtha. A diluent is used individually by 1 type or in combination of 2 or more types. Content in the case of using a diluent can be suitably adjusted from a viewpoint of the applicability | paintability of the photosensitive resin composition.

  The photosensitive resin composition of the present invention can be obtained by uniformly kneading and mixing the above-described components with a roll mill, a bead mill or the like.

  The photosensitive resin composition of the present invention can be used, for example, to form an image and produce a cured film as follows.

That is, it is applied to a copper-clad laminate with a film thickness of 10 to 200 μm by a screen printing method, a spray method, a roll coating method, a curtain coating method, an electrostatic coating method or the like, and the coating film is then applied at 60 to 110 ° C. After drying, the negative film is directly contacted (or non-contacted through a transparent film) and irradiated with active light (for example, ultraviolet light) with an exposure dose of preferably 10 to 1,000 mJ / cm ² , Thereafter, the unexposed portion is dissolved and removed (developed) with a dilute alkaline aqueous solution or an organic solvent. Next, the exposed portion is sufficiently cured by post-exposure (ultraviolet exposure) and / or post-heating to obtain a cured film. The post-exposure is preferably performed at an exposure amount of, for example, 1 to 5 J / cm ² , and the post-heating is preferably performed at 100 to 200 ° C. for 30 minutes to 12 hours.

  Moreover, the photosensitive resin composition of this invention can also be laminated | stacked on a support body, and it can also be set as a photosensitive element. The thickness of the layer made of the photosensitive resin composition is preferably 10 to 100 μm. As the support, a film having a thickness of 5 to 100 μm such as polyethylene terephthalate is preferably used. The layer made of the photosensitive resin composition is preferably formed by applying and drying a solution of the photosensitive resin composition on a support film.

  EXAMPLES Hereinafter, although this invention is demonstrated more concretely based on an Example and a comparative example, this invention is not limited to a following example.

[Synthesis Example 1: Production of acid-modified vinyl group-containing epoxy resin (A-1)]
Bisphenol F novolac type epoxy resin (trade name: EXA-7376, manufactured by DIC Corporation) 350 having a structural unit represented by the general formula (4) (R ¹³ is a hydrogen atom, two Y ³ are both glycidyl groups) Part by mass, 70 parts by mass of acrylic acid, 0.5 part by mass of methylhydroquinone, and 120 parts by mass of carbitol acetate were charged and reacted by heating to 90 ° C. and stirring to completely dissolve the mixture. Next, the obtained solution was cooled to 60 ° C., 2 parts by mass of triphenylphosphine was added, and the mixture was heated to 100 ° C. until the acid value of the solution reached 1 mgKOH / g. To the solution after the reaction, 98 parts by mass of tetrahydrophthalic anhydride (THPAC) and 85 parts by mass of carbitol acetate were added, heated to 80 ° C., reacted for about 6 hours, cooled, and the solid content was 73 parts by mass. % Solution of THPAC-modified bisphenol F type novolac epoxy acrylate (hereinafter referred to as “acid-modified vinyl group-containing epoxy resin (A-1)”) as a component (A).

(Examples 1-4, Comparative Examples 1-4)
Each material shown in the following Table 1 was blended in the blending amount (unit: parts by mass) shown in the same table, then kneaded with a three-roll mill, and carbitol acetate was added so that the solid content concentration became 70% by mass. A photosensitive resin composition was obtained. In addition, the compounding quantity of each material in following Table 1 shows the compounding quantity of solid content.

The details of each material in Table 1 are as follows.
* 1 (UE-EXP-3165): acid-modified vinyl group-containing epoxy resin (manufactured by DIC Corporation, trade name), structure represented by general formula (2) (in formula (2), R ¹¹ is a hydrogen atom, Y ¹ is acrylated glycidyl group, modifying the hydroxyl group in THPAC), weight average molecular weight of 3300, an acid value 42.4 mg / KOH. (The weight average molecular weight increases the softening point as the molecular weight increases, which contributes to improved heat resistance.)
* 2 (Acid-modified vinyl group-containing epoxy resin (A-1)): THPAC-modified bisphenol F type novolac epoxy acrylate prepared in Synthesis Example 1.
* 3 (Aronix M402): Dipentaerythritol hexaacrylate (manufactured by Toagosei Co., Ltd., trade name (“Aronix” is a registered trademark)).
* 4 (Irgacure 369): (trade name, manufactured by BASF Japan Ltd.).
* 5 (SFP-20M): silica fine particles (manufactured by Denki Kagaku Kogyo Co., Ltd., trade name (“SFP” is a registered trademark))
* 6 (ASA): Barium sulfate fine particles (trade name, manufactured by Solvay Chemicals)
* 7 (YSLV-80XY): Epoxy resin (manufactured by Nippon Steel Chemical Co., Ltd., trade name)
* 8 (RE-306): Epoxy resin (trade name, manufactured by Nippon Kayaku Co., Ltd.)
* 9 (PB-3600): Epoxidized polybutadiene (manufactured by Daicel Corporation, trade name)

[Light sensitivity]
The film thickness after drying is applied to the photosensitive resin compositions of Examples and Comparative Examples on a copper-clad laminate (manufactured by Hitachi Chemical Co., Ltd., trade name: MCL-E-67 ("MCL" is a registered trademark)). After applying by screen printing so as to be 15 μm, it was dried at 75 ° C. for 30 minutes using a hot air circulating dryer. On the surface of the obtained coating film, the density region is 0.00 to 2.00, the density step is 0.05, the size of the tablet (rectangle) is 20 mm × 187 mm, and the size of each step (rectangle) is 3 mm × 12 mm. A 41-step tablet with a phototool (Stofer) is closely attached, irradiated with ultraviolet rays with an integrated exposure amount of 100 mJ / cm ² and developed with a 1% by weight aqueous sodium carbonate solution for 60 seconds. The sensitivity was evaluated. The greater the number of remaining steps, the higher the sensitivity, and it is preferable that 8 or more steps remain. The evaluation results are shown in Table 2.

[Aperture diameter]
The photosensitive resin composition of an Example and a comparative example was screen-printed so that the film thickness after drying might be set to 15 micrometers on a copper clad laminated board (The Hitachi Chemical Co., Ltd. make, brand name: MCL-E-67). Then, it was dried at 75 ° C. for 30 minutes using a hot air circulating dryer. The obtained coating film was irradiated with ultraviolet rays having an accumulated exposure amount of 100 mJ / cm ² through a negative film in which light non-transparent portions having a diameter of 80 μm and a diameter of 110 μm were scattered in an area of 1 cm × 1 cm square, and 1% by mass Spray development was performed with an aqueous sodium carbonate solution for 60 seconds at a pressure of 1.8 kgf / cm ² , and the unexposed area was dissolved and developed to form an image. Thereafter, the opening diameter was measured using a microscope (trade name: KH-3000, manufactured by Hilox Co., Ltd.) and evaluated according to the following criteria. The evaluation results are shown in Table 2.
A: The aperture diameter is 80% or more (64 μm or more for a negative film having a diameter of 80 μm and 88 μm or more for a negative film having a diameter of 110 μm).
B: The aperture diameter is 70% or more and less than 80% (56 μm or more and less than 64 μm for a negative film with a diameter of 80 μm, 77 μm or more and less than 88 μm for a negative film with a diameter of 110 μm).
C: The aperture diameter is less than 70% (less than 56 μm for a negative film having a diameter of 80 μm and less than 77 μm for a negative film having a diameter of 110 μm).

[HAST resistance evaluation]
By etching the copper surface of a printed wiring board substrate (trade name: E-679, manufactured by Hitachi Chemical Co., Ltd.) in which a 12 μm thick copper foil is laminated on a glass epoxy substrate, the line / space is 28 μm / 32 μm. A comb electrode was formed. This substrate was used as an evaluation substrate, and a cured product of the resist was formed on the substrate as described above, and then exposed to conditions of 135 ° C., relative humidity 85%, and applied voltage 5 V for 200 hours. Thereafter, the degree of occurrence of migration was observed with a 100-fold metal microscope and evaluated according to the following criteria. That is, if the permanent resist film did not migrate and the resistance value did not decrease, the value was “3”, and the resistance value did not decrease, but if the migration value was “2”, a large migration occurred. In addition, the case where the resistance value also decreased was evaluated as “1”. The evaluation results are shown in Table 2.

[Evaluation of thermal expansion coefficient and glass transition point]
The photosensitive resin composition solution was uniformly applied on a 16 μm-thick polyethylene terephthalate film (trade name: G2-16, manufactured by Teijin Ltd.) as a support layer so that the film thickness after drying was 30 μm. Was dried at 75 ° C. for about 30 minutes using a hot air convection dryer. Subsequently, on the surface of the photosensitive resin composition layer opposite to the side in contact with the support, a polyethylene film (manufactured by Tamapoly Co., Ltd., trade name: NF-15) is bonded as a protective film, and photosensitive. A film laminate was obtained. The entire surface of the photosensitive film was exposed and then allowed to stand at room temperature (25 ° C.) for 1 hour, and then the polyethylene film was peeled off and spray-developed with a 1% by mass aqueous sodium carbonate solution at 30 ° C. After spray development, ultraviolet irradiation of ² J / cm ² was performed using an ultraviolet irradiation device manufactured by Oak Manufacturing Co., Ltd., followed by heat treatment at 170 ° C. for 60 minutes. Subsequently, after cutting out to 3 mm in width and 30 mm in length with a cutter knife, the polyethylene terephthalate on the cut-out laminated body was peeled, and the cured photosensitive resin (test piece) for thermal expansion coefficient evaluation was obtained. About the obtained test piece, the thermal expansion coefficient in a tension mode was measured using the TMA apparatus (the Seiko Instruments Inc. make, brand name: SS6000). The tensile load is 5 g, the span (distance between chucks) is 15 mm, and the heating rate is 10 ° C./min. First, the test piece was attached to the apparatus, heated from room temperature (25 ° C.) to 160 ° C., and left for 15 minutes. Then, it cooled to -60 degreeC, it measured on conditions with a temperature increase rate of 10 degree-C / min from -60 degreeC to 250 degreeC, and computed the glass transition point and the thermal expansion coefficient. The evaluation results are shown in Table 2.

  As is apparent from Table 2, Examples 1 to 4 are excellent in general characteristics such as resolution, electrical reliability (HAST resistance), low thermal expansion coefficient, and high Tg. Moreover, it turns out that what filled highly the inorganic filler is excellent in a thermal expansion coefficient and heat resistance, without degrading resolution. On the other hand, as is clear from Table 2, it can be seen that Comparative Examples 1 to 4 are insufficient in any of resolution, electrical reliability, coefficient of thermal expansion, and heat resistance. Therefore, according to the photosensitive resin composition of the present invention, it is possible to obtain a permanent mask resist that achieves a low coefficient of thermal expansion while maintaining resolution, is excellent in HAST resistance, and has a high Tg.

Claims (3)

A photosensitive resin composition comprising (A) an acid-modified vinyl group-containing epoxy resin, (B) a photopolymerizable monomer having an ethylenically unsaturated bond, (C) a photopolymerization initiator, and (D) an inorganic filler. Yes, the component (A) contains a compound represented by the following general formula (2) and a compound represented by the following general formula (3) or (4), and the content of the (D) inorganic filler The photosensitive resin composition whose is 20 mass% or more and 60 mass% or less with respect to the total solid content.

[In Formula (2), R ¹¹ represents a hydrogen atom or a methyl group, Y ¹ represents a hydrogen atom or a glycidyl group, and n 1 represents an integer of 1 or more. A plurality of R ¹¹ and Y ¹ may be the same or different. However, at least one Y ¹ represents a glycidyl group. ]

[In the formula (3), R ¹² represents a hydrogen atom or a methyl group, and Y ² represents a hydrogen atom or a glycidyl group. Two R ¹² may be the same or different, and two Y ² may be the same or different. However, at least one of Y ² represents a glycidyl group. ]

[In the formula (4), R ¹³ represents a hydrogen atom or a methyl group, and Y ³ represents a hydrogen atom or a glycidyl group. Two R ¹³ may be the same or different, and two Y ³ may be the same or different. However, at least one of Y ³ represents a glycidyl group. ]   (B) The photosensitive resin composition of Claim 1 whose photopolymerizable monomer which has an ethylenically unsaturated bond is a polyfunctional photopolymerizable monomer which has 3 or more of ethylenically unsaturated bonds in 1 molecule.   The photosensitive resin composition according to claim 1, further comprising (E) a pigment.