WO2019188895A1 - Unsaturated-group-containing alkali-soluble resin, photosensitive resin composition including unsaturated-group-containing alkali-soluble resin as essential ingredient, and cured product of photosensitive resin composition including unsaturated-group-containing alkali-soluble resin as essential ingredient - Google Patents

Abstract

An alkali-soluble resin that is represented by general formula (1) and has a carboxyl group and a polymerizable unsaturated group in each molecule thereof. A photosensitive resin composition that contains: (i) the alkali-soluble resin of general formula (1); (ii) a photopolymerizable monomer that has at least one polymerizable unsaturated group; (iii) a photopolymerization initiator; and (iv) an optional epoxy compound.

Description

Unsaturated group-containing alkali-soluble resin, photosensitive resin composition containing the same, and cured product thereof

The present invention relates to an unsaturated group-containing alkali-soluble resin, a photosensitive resin composition containing it as an essential component, and a cured product obtained by curing the same. The photosensitive resin composition and the cured product thereof according to the present invention include a solder resist, a plating resist, an etching resist for manufacturing a circuit board, an insulating film for multilayering a wiring board on which a semiconductor element is mounted, and a semiconductor gate insulating film. It can be applied to photosensitive adhesives.

With recent high performance and high definition of electronic devices and display members, electronic components used there are required to be downsized and high density. And in the workability of the insulating material used for them, refinement | miniaturization and optimization of the cross-sectional shape of the processed pattern have come to be requested | required. A method of patterning by exposure and development is known as an effective means for fine processing of an insulating material, and a photosensitive resin composition has been used there, but high sensitivity, adhesion to a substrate, reliability, Many characteristics such as heat resistance and chemical resistance have been demanded. In addition, various studies have been made to use an organic insulating material in a gate insulating film for an organic TFT, but it is necessary to reduce the operating voltage of the organic TFT by reducing the thickness of the gate insulating film. Here, in the case of an organic insulating material having a dielectric breakdown voltage of about 1 MV / cm, application of a thin film having an insulating film thickness of about 0.2 μm is under consideration.

A conventional insulating material made of a photosensitive resin composition uses a photocuring reaction by a reaction between a photoreactive alkali-soluble resin and a photopolymerization initiator, and mainly uses a mercury lamp as an exposure wavelength for photocuring. I line (365 nm), which is one of the line spectra, is used. However, the i-line is absorbed by the photosensitive resin itself or the colorant, and the photocuring degree is lowered. Moreover, the amount of absorption increases if the film is thick. Therefore, the exposed portion has a difference in crosslink density with respect to the film thickness direction. Thereby, even if it is sufficiently photocured on the surface of the coating film, it is difficult to photocure on the bottom surface of the coating film, so that it is extremely difficult to make a difference in crosslink density between the exposed part and the unexposed part. Accordingly, it is difficult to obtain a photosensitive insulating material that can be developed with high resolution having desired pattern dimension stability, development margin, pattern adhesion, pattern edge shape and cross-sectional shape.

In general, a photosensitive resin composition for such an application includes a polyfunctional photocurable monomer having a polymerizable unsaturated bond, an alkali-soluble binder resin, a photopolymerization initiator, and the like. A photosensitive resin composition that is technically disclosed as an application as a color filter material can be applied. For example, Patent Literature 1 and Patent Literature 2 disclose copolymers of (meth) acrylic acid or (meth) acrylic acid ester having a carboxyl group as a binder resin, maleic anhydride, and other polymerizable monomers. Has been. Patent Document 3 discloses that an alkali-soluble unsaturated compound having a polymerizable unsaturated group and a carboxyl group in one molecule is effective for forming a negative pattern such as a color filter.

On the other hand, Patent Document 4, Patent Document 5, Patent Document 6 and Patent Document 7 disclose liquid resins using a reaction product of an epoxy (meth) acrylate having a bisphenolfluorene structure and an acid anhydride.

Furthermore, Patent Document 8 discloses polyfunctionalization of an alkali-soluble resin composition that increases the molecular weight of a carboxyl group-containing copolymer.

Japanese Patent Laid-Open No. 61-213213 Japanese Unexamined Patent Publication No. 1-152449 JP-A-4-340965 JP-A-4-345673 JP-A-4-345608 JP-A-4-355450 JP-A-4-3631111 Japanese Patent Laid-Open No. 9-325494

However, since the copolymer disclosed in Patent Document 1 and Patent Document 2 is a random copolymer, a distribution of alkali dissolution rate occurs in the light-irradiated part and in the light-unirradiated part. Since the time margin becomes narrow, it is difficult to obtain an acute-angle pattern shape or a fine pattern.

Moreover, since the alkali-soluble unsaturated compound described in Patent Document 3 is insolubilized by light irradiation, it is expected to be highly sensitive compared to the combination of the binder resin and the polyfunctional polymerizable monomer described above. . Here, examples of the compound described in Patent Document 3 include those obtained by arbitrarily adding a polymerizable unsaturated bond acrylic acid and an acid anhydride to the hydroxyl group of the phenol oligomer. Also in the compound of Patent Document 3, since a wide distribution occurs in the molecular weight of each molecule and the amount of carboxyl groups, the alkali dissolution rate distribution of the alkali-soluble resin becomes wide, so that it is difficult to form a fine negative pattern. is there.

Also, examples of the resins described in Patent Document 4, Patent Document 5, Patent Document 6, and Patent Document 7 include a reaction product of epoxy (meth) acrylate and acid monoanhydride. Since this reaction product has a low molecular weight, it is difficult to increase the difference in alkali solubility between the exposed area and the unexposed area, so that a fine pattern cannot be formed.

In addition, since the copolymer described in Patent Document 8 has a low number of polymerizable unsaturated bonds and thus a sufficient crosslinking density cannot be obtained, the copolymer has an increased ratio of polymerizable unsaturated bonds in one molecule. There is room for structural improvements.

An object of the present invention is to provide a photosensitive resin composition capable of patterning with excellent resolution by alkali development. Furthermore, the cured product has a low coefficient of thermal expansion even when heat is applied in the processing process after pattern formation in a semiconductor process, etc., and has excellent chemical resistance when undergoing a processing process such as electrode formation. It is to provide a cured film having the characteristics shown.

As a result of intensive studies to solve the above-mentioned problems, the present inventors obtained (meth) acrylic acid by reacting with an epoxy compound having two or more glycidyl ether groups derived from a polymer of naphthols. A photosensitive resin composition using an alkali-soluble resin obtained by reacting a dicarboxylic acid, a tricarboxylic acid or an acid monoanhydride with a polyhydric alcohol having a polymerizable unsaturated group is an insulating material that requires photopatterning. It has been found that it is suitable for forming a cured film pattern such as a film.

That is, the embodiment of the present invention relates to (i) an alkali-soluble resin represented by the following general formula (1) and having a carboxyl group and a polymerizable unsaturated group in one molecule.

(X represents a divalent hydrocarbon group having 1 to 20 carbon atoms. The divalent hydrocarbon group may be linear or branched, and may have an aromatic ring in the main chain or branched chain. Y is a hydrocarbon group R having 1 to 5 carbon atoms or a substituent Z having a polymerizable unsaturated group and a carboxyl group in the molecule represented by the general formula (2), and the number of moles of _{R CR} , When the number of moles of _Z is C _Z , the value of C _R / C _Z is 0.05 to 2.0, the average value of n is 1 to 20. Further, the number of hydrogen atoms of the naphthalene ring A part thereof may be substituted with R ₁ , and R ₁ represents a hydrocarbon group having 1 to 5 carbon atoms, a halogen atom or a phenyl group.)

(R ₃ represents a hydrogen atom or a methyl group. L represents a substituent represented by the general formula (3).)

(M represents a divalent or trivalent carboxylic acid residue, and p is 1 or 2.)

Moreover, the embodiment of the present invention comprises (i) an alkali-soluble resin having a carboxyl group and a polymerizable unsaturated group in one molecule, and (ii) a photopolymerizable monomer having at least one polymerizable unsaturated group. And (iii) a photopolymerization initiator as an essential component.

Moreover, other embodiment of this invention is related with the hardened | cured material formed by hardening | curing the said photosensitive resin composition.

According to the present invention, a photosensitive resin composition capable of forming a fine cured film pattern by photolithography can be provided by including the alkali-soluble resin represented by the general formula (1). Furthermore, according to the present invention, it is possible to provide a cured film pattern that has low thermal expansion and excellent chemical resistance (alkali resistance and the like) and exhibits excellent properties such as adhesion to a substrate, heat resistance, and electrical reliability. it can.

Hereinafter, the photosensitive resin composition of the present invention will be described in detail. The present invention relates to a photosensitive resin composition containing an alkali-soluble resin represented by the general formula (1) as a main component, and a cured product obtained by curing the photosensitive resin composition.

The alkali-soluble resin represented by the general formula (1) is obtained by reacting (meth) acrylic acid with an epoxy compound having two or more glycidyl ether groups derived from a polymer of naphthols. It is obtained by reacting a polyhydric alcohol having a saturated group with a dicarboxylic acid, a tricarboxylic acid or an acid monoanhydride thereof.

Since the alkali-soluble resin represented by the general formula (1) has both a polymerizable unsaturated group and a carboxyl group, it has excellent photocurability, good developability, and patterning characteristics as an alkali-developable photosensitive resin composition. Have. Further, when the photosensitive resin composition is cured, it can contribute to low thermal expansion and alkali resistance.

The method for producing the alkali-soluble resin represented by the general formula (1) will be described in detail. First, the alkali-soluble resin of the general formula (1) has a naphthalene skeleton represented by the general formula (4) having two or more glycidyl ether groups obtained by converting a phenolic hydroxyl group of a naphthol polymer into glycidyl ether. It is derived from a polyhydric alcohol containing a polymerizable unsaturated group obtained by reacting an epoxy compound with (meth) acrylic acid. For the production method of the epoxy compound having a naphthol skeleton, for example, the production method described in JP-A-2006-160868 can be referred to.

In the general formula (4), X represents a divalent hydrocarbon group having 1 to 20 carbon atoms. The divalent hydrocarbon group may have a straight chain or a branch, and may have an aromatic ring in the main chain or the branched chain. Specifically, —CH ₂ —, —CH (CH ₃ ) —, —CH (C ₂ H ₅ ) —, —CH (C ₆ H ₅ ) —, general formula (5), general formula (6) and It is a bivalent coupling group represented by General formula (7). Here, it is preferable that a bivalent coupling group is General formula (5), General formula (6), and General formula (7). W represents a hydrocarbon group R or a glycidyl group G, of 1-5 carbon atoms, moles _C R of R, when the number of moles _{C G} of _G, C value of R / _{C G} 0.05-2 .0. R is preferably a methyl group or an ethyl group. When the resin of the general formula (4) is produced, it is usually obtained as a mixture of molecules having different numerical values n. The average value of n is preferably 1 to 20, and preferably 1 to 10. More preferred is 1-6. Furthermore, a part of the hydrogen atoms of the naphthalene ring of the general formula (4) may be substituted with the substituent R ₁ , and a part of the hydrogen atoms of the benzene ring of the general formulas (5) to (7) It may be substituted with R ₂ . R ₁ and R ₂ independently represent a hydrocarbon group having 1 to 5 carbon atoms, a halogen atom or a phenyl group.

The polymerization method of naphthols can be referred to general methods for producing phenol resins and phenol aralkyl resins, but is derived from a compound of the general formula (4) characterized by having a hydrocarbon group R. As a method for producing the above, the method described in JP-A-2006-160868 can be referred to. Specifically, as a first step, naphthols and a crosslinking agent are condensed in the presence of an acidic catalyst. 1-naphthol and / or 2-naphthol is used as a naphthol, and as a crosslinking agent, formaldehyde, acetaldehyde, Aldehyde compounds such as benzaldehyde; 1,4-bis (chloromethyl) benzene, 1,4-bis (chloroethyl) benzene, 4,4′-bis (chloromethyl) biphenyl, 4,4′-bis (chloromethylbiphenyl) Halogenated alkyl compounds such as ether; p-xylylene glycol, p-di (hydroxyethyl) benzene, 4,4′-bis (hydroxymethyl) biphenyl, 2,6-bis (hydroxymethyl) naphthalene, 2,2 ′ Alcohols such as bis (hydroxymethyl) diphenyl ether; p-xy Alcohols dialkyl ethers such as glycol dimethyl ether: divinyl benzene, divinyl compounds such as divinyl biphenyl can be exemplified. Here, the crosslinking agent used is 1,4-bis (chloromethyl) benzene, 1,4-bis (chloroethyl) benzene, 4,4′-bis (chloromethyl) biphenyl, p-xylylene glycol, p- Di (hydroxyethyl) benzene, p-xylylene glycol dimethyl ether, and 4,4′-bis (hydroxymethyl) biphenyl are preferred. The acidic catalyst can be appropriately selected from known inorganic acids and organic acids. For example, inorganic acids such as hydrochloric acid and sulfuric acid, organic acids such as formic acid, oxalic acid and p-toluenesulfonic acid, and Lewis acids such as aluminum chloride. Examples thereof include solid acids such as acid, activated clay, and zeolite. As a second step, a part of the hydroxyl groups of the resin obtained by reacting the naphthols with a crosslinking agent is alkoxylated. For example, the naphthol polymer of the present invention can be obtained by reacting the resin obtained in the first step with an alcohol under an acidic catalyst. Examples of the alcohol to be used include methanol, ethanol, propanol, butanol, pentanol and the like, and the catalyst exemplified in the first stage can be used as the acidic catalyst. As another method for obtaining a polymer of naphthols according to the present invention, when naphthols and a crosslinking agent are condensed in the presence of an acidic catalyst, in addition to 1-naphthol and / or 2-naphthol as naphthols, alkoxy You may use the manufacturing method of using a naphthalene together. Examples of the alkoxynaphthalene include 1-methoxynaphthalene, 2-methoxynaphthalene, 1-ethoxynaphthalene, 2-ethoxynaphthalene, 1-propoxynaphthalene and 2-propoxynaphthalene.

An epoxy compound having a naphthalene skeleton represented by the general formula (4) having two or more glycidyl ether groups can be obtained by converting a phenolic hydroxyl group of a polymer of naphthols into glycidyl ether. The production method can be carried out in the same manner as a normal hydroxyl group epoxidation reaction. For example, there is a method in which a polymer of naphthols is dissolved in excess epichlorohydrin and then reacted at 20 to 150 ° C. for 1 to 10 hours in the presence of an alkali metal hydroxide such as sodium hydroxide.

Next, a known method can be used for the reaction between such an epoxy compound and (meth) acrylic acid. For example, 2 mol of (meth) acrylic acid is used for 1 mol of epoxy group. Since (meth) acrylic acid is reacted with all of the epoxy groups, (meth) acrylic acid may be used in an amount slightly more than an equimolar amount of the epoxy group and the carboxyl group. The reaction product obtained by this reaction is an epoxy (meth) acrylate represented by the general formula (8).

(The definitions of X and n are the same as in the compound of the general formula (7), and Q has a hydrocarbon group having 1 to 5 carbon atoms or a polymerizable unsaturated group in the molecule represented by the general formula (9). Indicates a substituent.)

(R ₃ represents a hydrogen atom or a methyl group.)

The solvent, catalyst and other reaction conditions used at this time are not particularly limited. For example, the solvent preferably does not have a hydroxyl group and has a boiling point higher than the reaction temperature. Examples of such solvents include cellosolve solvents including ethyl cellosolve acetate and butyl cellosolve acetate; high boiling ethers or ester systems including diglyme, ethyl carbitol acetate, butyl carbitol acetate and propylene glycol monomethyl ether acetate. And ketone solvents including cyclohexanone and diisobutyl ketone. Examples of the catalyst include known catalysts such as ammonium salts including tetraethylammonium bromide and triethylbenzylammonium chloride; phosphines including triphenylphosphine and tris (2,6-dimethoxyphenyl) phosphine.

An alkali-soluble resin represented by the general formula (1) can be obtained by reacting the hydroxyl group of the compound represented by the general formula (8) with a dicarboxylic acid, a tricarboxylic acid or an acid monoanhydride thereof. Usually, since it reacts using an acid monoanhydride, it illustrates as an acid monoanhydride. Each hydrocarbon residue (structure excluding the carboxyl group) of these acid monoanhydrides may be further substituted with a substituent such as an alkyl group, a cycloalkyl group, or an aromatic group. Examples of saturated chain hydrocarbon dicarboxylic acids or tricarboxylic acid monoanhydrides include succinic acid, acetyl succinic acid, adipic acid, azelaic acid, citral malic acid, malonic acid, glutaric acid, citric acid, tartaric acid, oxoglutaric acid, Acid monoanhydrides such as pimelic acid, sebacic acid, suberic acid and diglycolic acid are included. Examples of acid monoanhydrides of saturated cyclic hydrocarbon dicarboxylic acids or tricarboxylic acids include acid monoanhydrides such as hexahydrophthalic acid, cyclobutane dicarboxylic acid, cyclopentane dicarboxylic acid, norbornane dicarboxylic acid, and hexahydrotrimellitic acid. Things are included. Examples of the acid monoanhydride of unsaturated dicarboxylic acid or tricarboxylic acid include acid monoanhydrides such as maleic acid, itaconic acid, tetrahydrophthalic acid, methylendomethylenetetrahydrophthalic acid, and chlorendic acid. Furthermore, examples of the acid monoanhydride of the aromatic hydrocarbon dicarboxylic acid or tricarboxylic acid include acid anhydrides such as phthalic acid and trimellitic acid. Among these, the acid monoanhydride is preferably an acid monoanhydride of succinic acid, itaconic acid, tetrahydrophthalic acid, hexahydrotrimellitic acid, phthalic acid, trimellitic acid, succinic acid, itaconic acid, More preferred is acid monoanhydride of tetrahydrophthalic acid. These acid monoanhydrides can be used alone or in combination of two or more.

The hydroxyl group of the compound represented by the general formula (8) is reacted with dicarboxylic acid or tricarboxylic acid or their acid monoanhydrides. The reaction temperature for synthesizing the compound represented by the general formula (1) is preferably 20 to 120 ° C., more preferably 40 to 90 ° C. The molar ratio of the acid monoanhydride when synthesizing the compound represented by the general formula (1) can be arbitrarily changed for the purpose of adjusting the acid value of the alkali-soluble resin represented by the general formula (1).

The photosensitive resin composition of the present invention comprises an alkali-soluble resin represented by the general formula (1) in (i) in a solid content excluding a solvent (the solid content includes a monomer that becomes a solid content after curing). It is preferable to contain 30 mass% or more, and it is more preferable to contain 50 mass% or more.

In order to take advantage of the characteristics of the photosensitive resin composition, it is preferable to contain the following components (i) to (iii) as essential components, and it is more preferable to contain the component (iv) as essential components.
(I) an alkali-soluble resin having a carboxyl group and a polymerizable unsaturated group in one molecule represented by the general formula (1);
(Ii) a photopolymerizable monomer having at least one polymerizable unsaturated group,
(Iii) a photopolymerization initiator,
(Iv) Epoxy compound

Among these, examples of the photopolymerizable monomer having at least one polymerizable unsaturated group as component (ii) include 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 2-hydroxy Monomers having a hydroxyl group such as ethylhexyl (meth) acrylate; ethylene glycol di (meth) acrylate, diethylene glycol di (meth) acrylate, triethylene glycol di (meth) acrylate, tetraethylene glycol di (meth) acrylate, tetramethylene glycol di ( (Meth) acrylate, trimethylolpropane tri (meth) acrylate, trimethylolethane tri (meth) acrylate, pentaerythritol di (meth) acrylate, pentaerythritol tri (meth) acrylate, pentae Examples include (meth) acrylic acid esters such as lithitol tetra (meth) acrylate, dipentaerythritol tetra (meth) acrylate, dipentaerythritol hexa (meth) acrylate, and glycerol (meth) acrylate. When it is necessary to form a crosslinked structure between molecules of the alkali-soluble resin, it is preferable to use a photopolymerizable monomer having two or more polymerizable unsaturated groups, and three or more polymerizable unsaturated groups. It is more preferable to use a photopolymerizable monomer having These compounds can be used alone or in combination of two or more.

The blending ratio [(i) / (ii)] of the component (ii) and the alkali-soluble resin [component (i)] represented by the general formula (1) is 20/80 to 90/10. Preferably, it is 40/60 to 80/20. Here, when there are few compounding ratios of alkali-soluble resin, the hardened | cured material after photocuring reaction will become weak. Moreover, since the acid value of a coating film is low and the solubility with respect to an alkaline developing solution falls in an unexposed part, the problem that a pattern edge does not become shaky and sharp arises. On the contrary, when the blending ratio of the alkali-soluble resin is larger than the above range, the ratio of the photoreactive functional group in the resin is decreased, so that the formation of the crosslinked structure by the photocuring reaction may be insufficient. In addition, when the acid value in the resin component is too high, the exposed portion is highly soluble in an alkaline developer, so that the formed pattern is likely to be narrower than the target line width, and pattern loss is likely to occur. Problems may arise.

Examples of the photopolymerization initiator (iii) include acetophenone, 2,2-diethoxyacetophenone, p-dimethylacetophenone, p-dimethylaminopropiophenone, dichloroacetophenone, trichloroacetophenone, p-tert-butylacetophenone. Benzophenones such as benzophenone, 2-chlorobenzophenone, p, p'-bisdimethylaminobenzophenone; benzoin ethers such as benzyl, benzoin, benzoin methyl ether, benzoin isopropyl ether, benzoin isobutyl ether; 2- ( O-chlorophenyl) -4,5-phenylbiimidazole, 2- (O-chlorophenyl) -4,5-di (m-methoxyphenyl)) biimidazole, 2- (O-fluoropheny ) -4,5-diphenylbiimidazole, 2- (O-methoxyphenyl) -4,5-diphenylbiimidazole, biimidazole compounds such as 2,4,5-triarylbiimidazole; 2-trichloromethyl- 5-styryl-1,3,4-oxadiazole, 2-trichloromethyl-5- (p-cyanostyryl) -1,3,4-oxadiazole, 2-trichloromethyl-5- (p-methoxystyryl) ) -1,3,4-oxadiazole and other halomethylthiazole compounds; 2,4,6-tris (trichloromethyl) -1,3,5-triazine, 2-methyl-4,6-bis (trichloro) Methyl) -1,3,5-triazine, 2-phenyl-4,6-bis (trichloromethyl) -1,3,5-triazine, 2- (4-chlorophenyl)- , 6-Bis (trichloromethyl) -1,3,5-triazine, 2- (4-methoxyphenyl) -4,6-bis (trichloromethyl) -1,3,5-triazine, 2- (4-methoxy Naphthyl) -4,6-bis (trichloromethyl) -1,3,5-triazine, 2- (4-methoxystyryl) -4,6-bis (trichloromethyl) -1,3,5-triazine, 2- (3,4,5-trimethoxystyryl) -4,6-bis (trichloromethyl) -1,3,5-triazine, 2- (4-methylthiostyryl) -4,6-bis (trichloromethyl) -1 Halomethyl-s-triazine compounds such as 1,3,5-triazine; 1,2-octanedione, 1- [4- (phenylthio) phenyl]-, 2- (O-benzoyloxime), 1- (4- Phenyls Fanylphenyl) butane-1,2-dione-2-oxime-O-benzoate, 1- (4-methylsulfanylphenyl) butane-1,2-dione-2-oxime-O-acetate, 1- (4- O-acyloxime compounds such as methylsulfanylphenyl) butan-1-oneoxime-O-acetate; benzyldimethyl ketal, thioxanthone, 2-chlorothioxanthone, 2,4-diethylthioxanthone, 2-methylthioxanthone Sulfur compounds such as 2-isopropylthioxanthone; anthraquinones such as 2-ethylanthraquinone, octamethylanthraquinone, 1,2-benzanthraquinone, 2,3-diphenylanthraquinone; azobisisobutylnitrile, benzoyl peroxide, cumeneper Such as oxide Organic peroxides; thiol compounds such as 2-mercaptobenzimidazole, 2-mercaptobenzoxazole, 2-mercaptobenzothiazole; and tertiary amines such as triethanolamine and triethylamine. These photopolymerization initiators may be used alone or in combination of two or more.

The addition amount of the photopolymerization initiator is preferably 0.1 to 10 parts by mass with respect to 100 parts by mass of the total amount of (i) alkali-soluble resin and (ii) photopolymerizable monomer, and 2 to 5 parts by mass. More preferably, it is a part. Here, when the addition amount of the photopolymerization initiator is less than 0.1 parts by mass, sufficient sensitivity cannot be obtained, and when the addition amount of the photopolymerization initiator exceeds 10 parts by mass, a taper shape (film of development pattern cross section) is obtained. The halation in which the shape in the thickness direction does not become sharp and the hem is pulled is likely to occur. Furthermore, decomposition gas may be generated when exposed to a high temperature in a subsequent process.

Examples of the epoxy compound (iv) include phenol novolac type epoxy resins, cresol novolac type epoxy resins, bisphenol A type epoxy resins, bisphenol F type epoxy resins, bisphenol S type epoxy resins, biphenyl type epoxy resins, and alicyclic rings. An epoxy resin such as a formula epoxy resin, a compound having at least one epoxy group such as phenyl glycidyl ether, p-butylphenol glycidyl ether, triglycidyl isocyanurate, diglycidyl isocyanurate, allyl glycidyl ether, glycidyl methacrylate, and the like are included. When there is a need to increase the crosslinking density of the alkali-soluble resin, a compound having at least two epoxy groups is preferable.

When the epoxy compound (iv) is used, the addition amount is preferably in the range of 10 to 40 parts by mass with respect to 100 parts by mass in total of the components (i) and (ii). Here, one purpose of adding an epoxy compound is to reduce the amount of carboxyl groups remaining when a cured film is formed after patterning in order to increase the reliability of the cured film. If the amount of the epoxy compound used is less than 10 parts by mass, the moisture resistance reliability when used as an insulating film may not be ensured. Moreover, when there are more usage-amounts of an epoxy compound than 40 mass parts, there exists a possibility that the quantity for the photosensitive group in the resin component in the photosensitive resin composition may reduce, and the sensitivity for patterning may not fully be obtained. .

Photosensitivity comprising, as essential components, an alkali-soluble resin represented by general formula (1) of (i), (ii) a photopolymerizable monomer, (iii) a photopolymerization initiator, and (iv) an epoxy compound. The resin composition can be used by dissolving it in a solvent or blending various additives as required. That is, when the photosensitive resin composition of the present invention is used for insulating materials, it is preferable to use a solvent in addition to the essential components (i) to (iv). Examples of solvents include alcohols such as methanol, ethanol, n-propanol, isopropanol, ethylene glycol, propylene glycol; terpenes such as α- or β-terpineol; acetone, methyl ethyl ketone, cyclohexanone, N-methyl-2-pyrrolidone Ketones such as toluene; aromatic hydrocarbons such as toluene, xylene and tetramethylbenzene; cellosolve, methyl cellosolve, ethyl cellosolve, carbitol, methyl carbitol, ethyl carbitol, butyl carbitol, propylene glycol monomethyl ether, propylene glycol Monoethyl ether, dipropylene glycol monomethyl ether, dipropylene glycol monoethyl ether, triethylene glycol monomethyl ether, triethylene Glycol ethers such as glycol monoethyl ether; ethyl acetate, butyl acetate, cellosolve acetate, ethyl cellosolve acetate, butyl cellosolve acetate, carbitol acetate, ethyl carbitol acetate, butyl carbitol acetate, propylene glycol monomethyl ether acetate, propylene glycol monoethyl Acetic esters such as ether acetate are included. By dissolving and mixing these alone or in combination of two or more, a uniform solution-like composition can be obtained.

Further, the photosensitive resin composition of the present invention includes a curing accelerator, a thermal polymerization inhibitor, an antioxidant, a plasticizer, a filler, a leveling agent, an antifoaming agent, a coupling agent, and a surfactant as necessary. Etc. can be mix | blended. Among these, as the curing accelerator, for example, a known compound known as a curing accelerator, a curing catalyst, a latent curing agent and the like which are usually applied to an epoxy compound can be used, and a tertiary amine, a quaternary ammonium salt, a tertiary Examples include phosphine, quaternary phosphonium salts, boric acid esters, Lewis acids, organometallic compounds, imidazoles, diazabicyclo compounds, and the like. Examples of the thermal polymerization inhibitor and the antioxidant include hydroquinone, hydroquinone monomethyl ether, pyrogallol, tert-butylcatechol, phenothiazine, hindered phenol compounds, phosphorus heat stabilizers and the like. Examples of the plasticizer include dibutyl phthalate, dioctyl phthalate, tricresyl phosphate, and the like. Examples of the filler include glass fiber, silica, mica, alumina, precipitated barium sulfate, precipitated calcium carbonate and the like. Examples of antifoaming agents and leveling agents include silicone-based, fluorine-based, and acrylic compounds. Examples of coupling agents include vinyltrimethoxysilane, 3-methacryloxypropyltrimethoxysilane, 3- (glycidyloxy) propyltrimethoxysilane, 3-isocyanatopropyltriethoxysilane, 3-aminopropyltriethoxysilane, 3- (phenylamino) propyltrimethoxysilane, 3-ureidopropyltriethoxysilane are included. Examples of the surfactant include a fluorine-based surfactant, a silicone-based surfactant, and the like.

The photosensitive resin composition of the present invention comprises (i) an alkali-soluble resin represented by the general formula (1) in a solid content excluding a solvent (the solid content includes a monomer that becomes a solid content after curing). , (Ii) a photopolymerizable monomer, (iii) a photopolymerization initiator, and (iv) an epoxy compound in total of 70% by mass or more, preferably 80% by mass, more preferably 90% by mass or more. . The amount of the solvent varies depending on the target viscosity, but is preferably 10 to 80% by mass with respect to the total amount.

Moreover, the coating film (cured product) of the present invention is cured by, for example, applying a solution of a photosensitive resin composition to a substrate or the like, drying the solvent, and irradiating light (including ultraviolet rays and radiation). It is obtained by. Using a photomask or the like to provide a portion that is exposed to light and a portion that is not exposed to light, only the portion that is exposed to light is cured, and the other portion is dissolved in an alkaline solution to obtain a coating film having a desired pattern. .

Specific examples of each step of the film forming method by application and drying of the photosensitive resin composition are as follows. When applying the photosensitive resin composition to the substrate, a known solution dipping method, spray method, roller coater machine Any method such as a method using a land coater, a slit coater or a spinner can be adopted. After applying to a desired thickness by these methods, the film is formed by removing the solvent (pre-baking). Pre-baking is performed by heating with an oven, a hot plate or the like, vacuum drying, or a combination thereof. The heating temperature and heating time in the pre-baking can be appropriately selected depending on the solvent to be used, but for example, it is preferably performed at 80 to 120 ° C. for 1 to 10 minutes.

As the radiation used for the exposure, for example, visible light, ultraviolet light, far ultraviolet light, electron beam, X-ray or the like can be used, and the wavelength range of the radiation is preferably 250 to 450 nm. As a developer suitable for this alkali development, for example, an aqueous solution of sodium carbonate, potassium carbonate, potassium hydroxide, diethanolamine, tetramethylammonium hydroxide, or the like can be used. These developing solutions can be appropriately selected in accordance with the characteristics of the resin layer, but it is also effective to add a surfactant if necessary. The development temperature is preferably 20 to 35 ° C., and a fine image can be precisely formed using a commercially available developing machine, ultrasonic cleaner or the like. In addition, after alkali development, it is usually washed with water. As a development processing method, a shower development method, a spray development method, a dip (immersion) development method, a paddle (liquid accumulation) development method, or the like can be applied.

After the development as described above, a heat treatment (post-bake) is performed at 120 to 250 ° C. for 20 to 100 minutes. This post-baking is performed for the purpose of improving the adhesion between the patterned coating film and the substrate. This is performed by heating with an oven, a hot plate or the like, as in the pre-bake. The patterned coating film of this invention is formed through each process by the photolithographic method. Then, polymerization or curing (sometimes referred to as curing together) is completed by heat to obtain a cured film such as an insulating film having a desired pattern. The curing temperature at this time is preferably 140 to 250 ° C.

Since the photosensitive resin composition of the present invention has more polymerizable unsaturated groups in one molecule than conventional ones, photocurability is improved, and the crosslinking density after curing without increasing the amount of photopolymerization initiator. Can be increased. That is, when ultraviolet rays or electron beams are irradiated with a thick film, the cured portion is cured to the bottom, so that the difference in solubility with respect to the alkaline developer in the exposed portion and the unexposed portion is increased, so that pattern dimension stability, development margin, Pattern adhesion is improved, and a pattern can be formed with high resolution. Even in the case of a thin film, the sensitivity can be improved and the amount of remaining film in the exposed area can be greatly improved and peeling during development can be suppressed.

The photosensitive composition of the present invention includes a solder resist, a plating resist, an etching resist for manufacturing a circuit board, an insulating film for multilayering a wiring board on which a semiconductor element is mounted, a semiconductor gate insulating film, a photosensitive adhesive ( In particular, it is extremely useful for adhesives that require heat bonding performance even after pattern formation by photolithography.

Hereinafter, the present invention will be described in more detail based on examples of the alkali-soluble resin represented by the general formula (1). The scope of the present invention is not limited by these examples. Moreover, evaluation of the resin in these Examples was performed as follows unless otherwise indicated.

[Solid content]
The solid content concentration was measured by impregnating a glass filter [mass: W0 (g)] with the resin solution, photosensitive resin composition, etc. (1 g) obtained in Example 1 (and Comparative Example 1) [W1 (G)] was calculated from the following formula using the value of mass [W2 (g)] after heating at 160 ° C. for 2 hours.
Solid content concentration (mass%) = 100 × (W2-W0) / (W1-W0)

[Acid value]
The acid value was determined by dissolving the resin solution in dioxane and titrating with a 1/10 N-KOH aqueous solution using a potentiometric titrator “COM-1600” (manufactured by Hiranuma Sangyo Co., Ltd.). Was the acid value.

[Molecular weight]
The molecular weight is determined by gel permeation chromatography (GPC) ("HLC-8220GPC" manufactured by Tosoh Corporation, column: TSKgelSuperH2000 (2) + TSKgelSuperH3000 (1) + TSKgelSuperH4000 (1) + TSKgelSuperH5000 (1 east) (Made by company), solvent: tetrahydrofuran, temperature: 40 ° C., speed: 0.6 ml / min), and a value obtained as a converted value of standard polystyrene (“PS-oligomer kit” manufactured by Tosoh Corporation) is a weight average molecular weight. (Mw).

Abbreviations used in Example 1 and Comparative Example 1 are as follows.
NAMMEA: Compound obtained by reacting methanol with a reaction product of 1-naphthol and p-xylylene glycol dimethyl ether (naphthol aralkyl resin) to methoxylate a part of hydroxyl groups (the ratio of methoxy groups to the total amount of hydroxyl groups and methoxy groups is 28 %) Epoxy compound obtained by reacting chloromethyloxirane (epoxy equivalent 406, in general formula (4), X is general formula (5), W is methyl group (R) and glycidyl group (G)) the C R _/ C value of _G is 0.39), the compound was further obtained by reacting acrylic acid (equal equivalent reaction product of the epoxy group and a carboxyl group)
THPA: 1,2,3,6-tetrahydrophthalic anhydride TEAB: tetraethylammonium bromide PEGMEA: propylene glycol monomethyl ether acetate

Example 1 below is a synthesis example of an alkali-soluble resin represented by the general formula (1) and having a carboxyl group and a polymerizable unsaturated group in one molecule. Comparative Example 1 is an alkali-soluble resin having a structure different from that of the alkali-soluble resin of the general formula (1).

[Example 1]
(Synthesis of alkali-soluble resin)
Into a 1000 ml four-necked flask equipped with a reflux condenser, 50% PEGMEA solution (337.2 g), THPA (49.1 g), TEAB (0.90 g), and PEGMEA (5.4 g) were charged. The mixture was stirred at 120 to 125 ° C. for 6 hours to obtain an alkali-soluble resin (i) -1. The obtained resin had a solid content concentration of 56.0% by mass, an acid value (in terms of solid content) of 88.0 mgKOH / g, and a molecular weight (Mw) of 1000.

[Comparative Example 1]
(Synthesis of alkali-soluble resin)
50% PGMEA solution (291.0 g) of bisphenol A type epoxy compound (epoxy equivalent = 182) and equivalent reaction product of acrylic acid (epoxy group and carboxyl group are equivalent) in a 1000 ml four-necked flask with a reflux condenser Then, dimethylolpropionic acid (4.0 g), 1,6-hexanediol (11.8 g), and PGMEA (84 g) were charged, and the temperature was raised to 45 ° C. Next, isophorone diisocyanate (61.8 g) was added dropwise while paying attention to the temperature in the flask. After completion of dropping, the mixture was stirred at 75 to 80 ° C. for 6 hours. Further, THPA (21.0 g) was charged and stirred at 90 to 95 ° C. for 6 hours to obtain an alkali-soluble resin solution (i) -2. The obtained resin had a solid content concentration of 66.5% by mass, an acid value (in terms of solid content) of 38.4 mgKOH / g, and a molecular weight (Mw) of 12,220.

Next, the present invention will be specifically described based on Example 2 and Comparative Example 2 for the production and evaluation of the photosensitive resin composition and its cured product, but the present invention is not limited thereto. . Here, the raw materials and abbreviations used in Example 2 and Comparative Example 2 below are as follows.

(i) -1: Alkali-soluble resin obtained in Example 1 (i) -2: Alkali-soluble resin obtained in Comparative Example 1 (ii): Dipentaerythritol hexaacrylate (iii) -1: Irgacure 184 ( "BASF's" Irgacure "is a registered trademark of the company.)
(iii) -2: 4,4'-bis (dimethylamino) benzophenone (Michler's ketone)
(iv): Cresol novolac type epoxy resin Solvent: Propylene glycol monomethyl ether acetate

The photosensitive resin compositions of Example 2 and Comparative Example 2 were prepared by blending each component at the ratio shown in Table 1. In addition, all the numerical values in Table 1 represent mass%.

[Evaluation of Photosensitive Resin Compositions of Example 2 and Comparative Example 2]
The photosensitive resin composition shown in Table 1 was coated on a 125 mm × 125 mm glass substrate using a spin coater so that the film thickness after post-baking was 30 μm, and pre-baked at 110 ° C. for 5 minutes to be coated. Was made. Thereafter, ultraviolet light having a wavelength of 365 nm was irradiated through a photomask for pattern formation with a high-pressure mercury lamp of 500 W / cm ² to carry out photocuring reaction of the exposed portion. Next, this exposed coated plate is further developed for 30 seconds from the time when the pattern started to appear in a 0.8 mass% tetramethylammonium hydroxide (TMAH) aqueous solution and 23 ° C. shower development, and further washed with spray water. The unexposed part of the coating film was removed. Thereafter, heat curing treatment was performed at 230 ° C. for 30 minutes using a hot air dryer, and cured films according to Example 2 and Comparative Example 2 were obtained.

The following evaluation was performed on the cured film obtained under the above conditions. In the preparation of a cured film for a film thickness test, an alkali resistance test, and an acid resistance test, development, washing with water, and heat curing treatment were performed after the entire surface exposure without passing through a photomask.

[Film thickness]
The film thickness was measured using a stylus step shape measuring device “P-10” (manufactured by KLA-Tencor Corporation) after shaving a part of the applied film.

[Alkali resistance test]
In the alkali resistance test, a glass substrate with a cured film was immersed in a solution kept at 80 ° C. of a mixed solution of 30 parts by mass of 2-aminoethanol and 70 parts by mass of glycol ether, pulled up after 10 minutes, washed with pure water, and dried. Then, a chemical-immersed sample was prepared and the adhesion was evaluated. A crosscut was put on the film of the sample immersed in the chemical so as to form at least 100 grids, and then a peeling test was performed using a cellophane tape, and the grids were visually evaluated.
A: No peeling at all ○: A slight peeling can be confirmed on the coating film Δ: A peeling can be confirmed on a part of the coating film ×: The film is almost peeled off

[Acid resistance test]
In the acid resistance test, the glass substrate with a cured film was immersed in a solution of aqua regia (hydrochloric acid: nitric acid = 7: 3) held at 50 ° C., pulled up after 10 minutes, washed with pure water, dried, and immersed in chemicals. Samples prepared were evaluated for adhesion. A crosscut was put on the film of the sample immersed in the chemical so as to form at least 100 grids, and then a peeling test was performed using a cellophane tape, and the grids were visually evaluated.
A: No peeling at all ○: A slight peeling can be confirmed on the coating film Δ: A peeling can be confirmed on a part of the coating film ×: The film is almost peeled off

[Heat resistance test]
In the heat resistance test, the photosensitive resin composition shown in Table 1 was applied on a glass substrate on which a 125 mm × 125 mm release film was pasted using a spin coater so that the film thickness after post-baking was 30 μm, A coated plate was prepared by pre-baking at 110 ° C. for 5 minutes. Thereafter, ultraviolet light having a wavelength of 365 nm was irradiated through a photomask for pattern formation with a high-pressure mercury lamp of 500 W / cm ² to carry out photocuring reaction of the exposed portion. Next, the exposed coated plate is further developed for 30 seconds from the time when the pattern started to appear by a 0.8% by weight tetramethylammonium hydroxide (TMAH) aqueous solution and 23 ° C. shower development, and further washed with spray water. The unexposed part of the coating film was removed. Thereafter, heat curing treatment was performed at 230 ° C. for 30 minutes using a hot air dryer, and the obtained pattern was peeled from the release film to obtain cured films according to Example 2 and Comparative Example 2.

The heat resistance of the insulating film obtained under the above conditions was evaluated by measuring the linear expansion coefficient (α1) using a thermomechanical analyzer (TMA).

As shown in Table 2, the photosensitive resin composition containing the alkali-soluble resin prepared in Example 2 and the cured product thereof show good results for the alkali resistance test, acid resistance test, and heat resistance test. I understood. Therefore, it is considered that the photosensitive resin composition containing the alkali-soluble resin of the present invention and the cured product thereof can form a fine cured film pattern by photolithography.

From the above, the photosensitive resin composition of the present invention and the cured product thereof are a solder resist, a plating resist, an etching resist for circuit board production, an insulating film for multilayering a wiring board on which a semiconductor element is mounted, a semiconductor It can be applied to a gate insulating film, a photosensitive adhesive, and the like.

This application claims priority based on Japanese Patent Application No. 2018-060780 filed on Mar. 27, 2018. All the contents described in the application specification are incorporated herein by reference.

Claims (6)

1. An alkali-soluble resin represented by the following general formula (1) and having a carboxyl group and a polymerizable unsaturated group in one molecule.
   

   

   (X represents a divalent hydrocarbon group having 1 to 20 carbon atoms. The divalent hydrocarbon group may be linear or branched, and may have an aromatic ring in the main chain or branched chain. Y is a hydrocarbon group R having 1 to 5 carbon atoms or a substituent Z having a polymerizable unsaturated group and a carboxyl group in the molecule represented by the general formula (2), and the number of moles of _{R CR} , When the number of moles of _Z is C _Z , the value of C _R / C _Z is 0.05 to 2.0, the average value of n is 1 to 20. Further, the number of hydrogen atoms of the naphthalene ring A part thereof may be substituted with R ₁ , and R ₁ represents a hydrocarbon group having 1 to 5 carbon atoms, a halogen atom or a phenyl group.)
   

   

   (R ₃ represents a hydrogen atom or a methyl group. L represents a substituent represented by the general formula (3).)
   

   

   (M represents a divalent or trivalent carboxylic acid residue, and p is 1 or 2.)
2. (I) an alkali-soluble resin having a carboxyl group and a polymerizable unsaturated group in one molecule according to claim 1;
   (Ii) a photopolymerizable monomer having at least one polymerizable unsaturated group;
   (Iii) a photopolymerization initiator;
   Is contained as an essential component.
3. 3. The photosensitive resin composition according to claim 2, further comprising (iv) an epoxy compound as an essential component.
4. The photosensitive property according to claim 2 or 3, wherein 0.1 to 10 parts by mass of component (iii) is contained with respect to 100 parts by mass in total of component (i) and component (ii). Resin composition.
5. (iii) 0.1 to 10 parts by mass of component (iii) and 10 to 40 parts by mass of component (iv) with respect to 100 parts by mass in total of component (i) and component (ii), Item 4. The photosensitive resin composition according to Item 3.
6. A cured product obtained by curing the photosensitive resin composition according to any one of claims 2 to 5.