Epoxy acrylate resin, alkali-soluble resin, resin composition including the same, and cured product thereof

Abstract

To provide: an epoxy acrylate resin or alkali-soluble resin that can be cured by light or heat; and a photosensitive resin composition capable of patterning through alkaline development.SOLUTION: The epoxy acrylate resin is represented by general formula (1) and obtained by reacting a (meth)acrylic acid with an epoxidized resin of dicyclopentadiene-type phenol resin. In addition, the alkali-soluble resin is obtained by reacting the epoxy acrylate resin with polyvalent carboxylic acids. In general formula (1), X is represented by formula (1a).SELECTED DRAWING: None

Description

[Technical field]

[0001] The present invention relates to an epoxy acrylate resin, a curable resin composition using the same, an unsaturated group-containing alkali-soluble resin, a photosensitive resin composition containing the same as an essential component, and a cured product thereof. The curable resin composition, photosensitive resin composition, and cured product thereof of the present invention are applicable to permanent protective films such as overcoats, undercoats, and insulating coats for producing circuit boards, solder resists, plating resists, and etching resists, insulating films for multilayering wiring boards on which semiconductor elements are mounted, semiconductor gate insulating films, photosensitive adhesives, and the like. [Background technology]

[0002] Solder resist ink is used for insulating protective coating of exposed conductor circuits of printed wiring boards and for preventing solder adhesion to solder-free parts of circuits. Screen printing has been the usual method for forming the coating, and the cured coating is required to have solder heat resistance, moisture resistance, adhesion, chemical resistance, plating resistance, and electrolytic corrosion resistance. There are two types of solder resist: heat-curing and ultraviolet-curing. The former is mainly made of epoxy resin, and the latter of epoxy acrylate resin. However, in recent years, due to the finer conductor circuit patterns and improved positional accuracy in various printed wiring boards, and further the miniaturization of mounted parts, the formation of insulating coatings using solder resist has been replaced by image formation using the photo method, which is becoming mainstream. In addition, organic solvents have been used in the past for developing resists using the photo method, but it is desirable to use dilute alkaline aqueous solutions from the viewpoint of air pollution and safety. Due to this background, there is a problem that the epoxy resins and epoxy acrylate resins compatible with conventional screen printing are not satisfactory for solder resists.

[0003] For example, phenol novolac type epoxy acrylate resins, bisphenol A epoxy acrylate resins, or half esters obtained by reacting these epoxy acrylate resins with acid dianhydrides are known as a solution for photoprocessing or dilute alkaline aqueous solution development (Patent Documents 1 and 2). However, when these known epoxy acrylate resins or their acid anhydride-modified products are used as a resin composition for solder resist, although the developability of dilute alkaline aqueous solution is satisfactory, a curing temperature of at least 180°C is required to stabilize the physical properties, which not only requires high costs for heating equipment, but also may cause discoloration or warping of the substrate when a glass epoxy substrate is used as the core substrate, for example, due to the high curing temperature. Furthermore, the cured coating obtained from these known epoxy acrylate resins or their acid anhydride-modified products has problems such as insufficient solder heat resistance, moisture resistance, adhesion, chemical resistance, plating resistance, or electrolytic corrosion resistance.

[0004] In recent years, with the increasing density of printed wiring boards, there has been a demand for reliability, resistance to pressure cookers, and resistance to thermal cycles in insulating layers for chip mounting boards, such as build-up boards for multi-chip modules (MCMs) and chip size packages (CSPs). However, when the above-mentioned known epoxy acrylate resins or their acid anhydride modified products are used as resin compositions for solder resists, there is a problem that they are unable to exhibit sufficient reliability.

[0005] In addition, with the recent trend toward higher performance and higher definition in electronic devices and display members, electronic components used therein are required to be smaller and more dense. In addition, the insulating materials used therein are also required to be finer and have a more appropriate cross-sectional shape of the processed pattern. A patterning method using exposure and development is known as an effective means for fine processing of insulating materials, and a photosensitive resin composition has been used therein, but many characteristics such as high sensitivity, adhesion to the substrate, reliability, heat resistance, and chemical resistance are required. In addition, various studies have been conducted on the use of organic insulating materials in the gate insulating film for organic TFTs, but it is necessary to reduce the operating voltage of the organic TFT by thinning the gate insulating film. Here, in the case of an organic insulating material with a dielectric strength of about 1 MV / cm, the application of a thin insulating film with a thickness of about 0.2 μm is being considered.

[0006] In the conventional insulating material made of a photosensitive resin composition, a photocuring reaction caused by a reaction between a photoreactive alkali-soluble resin and a photopolymerization initiator is utilized, and i-rays (365 nm), which are one of the line spectra of mercury lamps, are mainly used as the exposure wavelength for photocuring. However, this i-ray is absorbed by the photosensitive resin itself and the colorant, causing a decrease in the degree of photocuring. Moreover, the amount of absorption increases if the film is thick. Therefore, the exposed part has a difference in crosslink density in the film thickness direction. As a result, even if the coating film surface is sufficiently photocured, it is difficult to photocur the bottom surface of the coating film, so it is extremely difficult to make a difference in crosslink density between the exposed part and the unexposed part. As a result, it is difficult to obtain a photosensitive insulating material that can be developed with high resolution and has the desired pattern dimensional stability, development margin, pattern adhesion, pattern edge shape and cross-sectional shape.

[0007] 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 of a color filter, etc. However, since a wide distribution occurs in the molecular weight of each molecule and the amount of carboxyl group, the distribution of the alkali dissolution rate of the alkali-soluble resin becomes wide, making it difficult to form a fine negative pattern.

[0008] Furthermore, Patent Document 4 discloses multifunctionalization of an alkali-soluble resin composition to increase the molecular weight of a carboxyl group-containing copolymer. However, the number of polymerizable unsaturated bonds is small, and sufficient crosslinking density cannot be obtained, so there is room for improvement in the copolymer structure, such as increasing the proportion of polymerizable unsaturated bonds in one molecule.

[0009] In addition, the use of photosensitive resin compositions as interlayer insulating films in semiconductor devices and planarizing films for covering TFT electrodes in liquid crystal display devices is also being considered. In this case, the photosensitive resin composition is required to have a low dielectric constant so as not to impair the function of the device.

[0010] Due to the constraints of heat resistance of the substrate material and the viewpoint of manufacturing equipment, etc., there was no material that could be cured at low temperatures, could be developed using dilute alkaline water by the photo method, could reduce the dielectric constant, and fully satisfied the reliability required for an insulating layer cured film of a high-density mounting substrate, such as the adhesion and chemical resistance required for a solder resist of a printed wiring board. [Prior art documents] [Patent documents]

[0011] [Patent Document 1] Japanese Patent Application Publication No. 61-243869 [Patent Document 2] JP 2003-026762 A [Patent Document 3] Japanese Patent Application Publication No. 4-340965 [Patent Document 4] Japanese Patent Application Publication No. 9-325494 Summary of the Invention

[0012] Therefore, an object of the present invention is to provide a novel epoxy acrylate resin that can be photo- or thermally cured and has good dielectric properties, or to provide a photosensitive resin composition that can be patterned by alkaline development. Further, an object of the present invention is to provide a curable resin composition and a cured product thereof that have good dielectric properties and excellent reliability such as adhesion and chemical resistance required for solder resists and insulating films of printed wiring boards, and to provide a cured product (cured film) that shows excellent chemical resistance when subjected to processing processes such as electrode formation.

[0013] Means for Solving the Problems The present inventors have conducted intensive studies to solve the above problems, and as a result, have found that a curable resin composition using an epoxy acrylate resin obtained by reacting an epoxidized dicyclopentadiene-type phenolic resin having a dicyclopentenyl group as a substituent with (meth)acrylic acid is suitable for obtaining a cured product (insulating film) having excellent reliability, and that a photosensitive resin composition using an alkali-soluble resin obtained by reacting the epoxy acrylate resin with a dicarboxylic acid, a tricarboxylic acid, or an acid monoanhydride thereof is suitable for use as a solder resist or insulating film for printed wiring boards.

[0014] That is, the present invention relates to an epoxy acrylate resin represented by the following general formula (1). [ka] Where: R 1 each independently represents a hydrocarbon group having 1 to 8 carbon atoms; R 2 each independently represents a hydrogen atom or a dicyclopentenyl group, and one or more of them are dicyclopentenyl groups. R 3 represents a hydrogen atom or a methyl group. X is an unsaturated bond-containing group represented by the above formula (1a). n indicates the number of repetitions, and its average value is 1 to 5.

[0015] The present invention also relates to an alkali-soluble resin represented by the following general formula (2) and having a carboxyl group and a polymerizable unsaturated group in one molecule. [ka] Here, R 1 , R 2 , R 3 are synonymous with general formula (1). Y is an unsaturated bond-containing group represented by the above formula (2a), L is a hydrogen atom or a carboxyl group-containing group represented by the above formula (3), and 50 mol % or more of L are carboxyl group-containing groups. M is a carboxylic acid residue having a valence of p+1, and p is 1 or 2.

[0016] The present invention also relates to a curable resin composition comprising the above epoxy acrylate resin and a polymerization initiator.

[0017] The present invention also provides a photosensitive resin composition comprising the above-mentioned alkali-soluble resin, a photopolymerizable monomer having at least one polymerizable unsaturated group, and a photopolymerization initiator. This photosensitive resin composition preferably further comprises an epoxy resin.

[0018] Another embodiment of the present invention relates to a cured product obtained by curing the above-mentioned curable resin composition or the above-mentioned photosensitive resin composition.

[0019] The epoxy acrylate resin of the present invention can be cured by light or heat, and is also useful as an intermediate for an alkali-soluble resin, which is an acid anhydride adduct thereof. The alkali-soluble resin of the present invention provides a photosensitive resin composition capable of forming a fine cured film pattern by photolithography. Furthermore, according to the present invention, since the composition has excellent chemical resistance (alkali resistance, etc.), adhesion to a substrate, heat resistance, electrical reliability, etc., it can also provide a cured film pattern such as a solder resist for a printed wiring board or an insulating film that requires photopatterning. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0020] The present invention will be described in detail below. The epoxy acrylate resin of the present invention is represented by the above general formula (1). In the general formula (1), R 1 represents a hydrocarbon group having 1 to 8 carbon atoms, and is preferably an alkyl group having 1 to 8 carbon atoms, an aryl group having 6 to 8 carbon atoms, an aralkyl group having 7 to 8 carbon atoms, or an allyl group. The alkyl group having 1 to 8 carbon atoms may be linear, branched, or cyclic, and examples thereof include, but are not limited to, hydrocarbon groups such as methyl, ethyl, n-propyl, isopropyl, n-butyl, sec-butyl, isobutyl, t-butyl, n-pentyl, isopentyl, neopentyl, t-pentyl, methylbutyl, n-hexyl, dimethylbutyl, n-heptyl, methylhexyl, trimethylbutyl, n-octyl, dimethylpentyl, ethylpentyl, isooctyl, and ethylhexyl, and cycloalkyl groups having 5 to 8 carbon atoms such as cyclohexyl, cycloheptyl, cyclooctyl, methylcyclohexyl, dimethylcyclohexyl, ethylcyclohexyl, and methylcycloheptyl. Examples of aryl groups having 6 to 8 carbon atoms include, but are not limited to, phenyl, tolyl, xylyl, and ethylphenyl. Examples of the aralkyl group having 7 to 8 carbon atoms include, but are not limited to, a benzyl group, an α-methylbenzyl group, etc. Among these substituents, from the viewpoints of availability and reactivity when a cured product is formed, a methyl group or a phenyl group is preferred, and a methyl group is particularly preferred.

[0021] Above R 2 are independently a hydrogen atom or a dicyclopentenyl group, and one or more are dicyclopentenyl groups. The dicyclopentenyl group is a group derived from dicyclopentadiene and is represented by the following formula (1b) or formula (1c). The presence of this group can reduce the dielectric constant of the cured product of the epoxy acrylate resin of the present invention. [ka]

[0022] n is the number of repetitions and is a number equal to or greater than 1, and the average value is a number from 1 to 5, preferably from 1.1 to 4.0, more preferably from 1.2 to 3.0, and even more preferably from 1.3 to 2.0. The average value is a number average.

[0023] X is an unsaturated bond-containing group represented by formula (1a), R 3 represents a hydrogen atom or a methyl group. In formulae (1a), (2a) and (3), CO is a carbonyl group (C=O) and may be represented by either CO or OC.

[0024] The epoxy acrylate resin of general formula (1) can be advantageously obtained by reacting an epoxy resin represented by the following general formula (4) with (meth)acrylic acid. The epoxy resin is obtained by epoxidizing a dicyclopentadiene-type phenolic resin obtained by reacting a 2,6-disubstituted phenol with dicyclopentadiene.

[0025] [ka] Here, R 1 , R 2 and n are defined as in formula (1). G represents a glycidyl group.

[0026] The reaction of the epoxy resin with (meth)acrylic acid can be carried out by a known method. For example, the reaction is carried out by using an equimolar amount of (meth)acrylic acid relative to the epoxy groups. In order to react all the epoxy groups with (meth)acrylic acid, the amount of (meth)acrylic acid may be slightly in excess of the equimolar amount of the epoxy groups and the carboxyl groups. The reaction temperature is usually 50 to 150°C, and the reaction time is 1 to 20 hours. The solvent, catalyst, and other reaction conditions used at this time are not particularly limited.

[0027] The solvent is preferably one that does not have a hydroxyl group and has a boiling point higher than the reaction temperature, for example. Examples of such solvents include cellosolve-based solvents including ethyl cellosolve acetate and butyl cellosolve acetate, high-boiling ether or ester-based solvents including diglyme, ethyl carbitol acetate, butyl carbitol acetate, and propylene glycol monomethyl ether acetate, ketone-based solvents including cyclohexanone and diisobutyl ketone, and aromatic compounds such as benzene, toluene, chlorobenzene, and dichlorobenzene.

[0028] Examples of the catalyst include known catalysts such as amines such as triethylamine and 1,4-diaza[5,4,0]bicycloundecene-7; ammonium salts such as tetraethylammonium bromide and triethylbenzylammonium chloride; phosphines such as triphenylphosphine and tris(2,6-dimethoxyphenyl)phosphine; and imidazoles such as 2-methylimidazole and 2-ethyl-4-methylimidazole.

[0029] Furthermore, during the reaction, a polymerization inhibitor such as hydroquinone, 4-methylquinoline, or phenothiazine may be added. In order to inhibit a polymerization reaction due to an unsaturated bond, the reaction may be carried out under a stream of air or the like, as the case may be.

[0030] In addition, the method for producing the epoxy resin, which is the raw material of the epoxy acrylate resin, can refer to the method described in, for example, JP-A-5-339341. The epoxy resin is prepared by first synthesizing a phenolic resin represented by the following general formula (5) by reacting a 2,6-disubstituted phenolic compound with dicyclopentadiene in the presence of a catalyst such as boron trifluoride ether complex, and then reacting the resulting phenolic resin with an epihalohydrin such as epichlorohydrin to epoxidize it.

[0031] [ka] Here, R 1 , R 2 and n are each defined as in general formula (1).

[0032] The phenol resin can be obtained by reacting 2,6-disubstituted phenol with dicyclopentadiene at a predetermined ratio, and dicyclopentadiene may be added in several stages (two or more divided successive additions) to react intermittently. The ratio is 0.28 to 2 times the molar amount of dicyclopentadiene relative to 2,6-disubstituted phenol. When dicyclopentadiene is continuously added and reacted, the ratio is 0.25 to 1 times the molar amount of dicyclopentadiene relative to 2,6-disubstituted phenol, preferably 0.28 to 1 times the molar amount, and more preferably 0.3 to 0.5 times the molar amount. When dicyclopentadiene is added in divided successive additions and reacted, the total amount is preferably 0.8 to 2 times the molar amount, and more preferably 0.9 to 1.7 times the molar amount. In this case, the ratio of dicyclopentadiene used in each stage is preferably 0.28 to 1 times the molar amount. Dicyclopentadiene serves as a bridging group connecting 2,6-disubstituted phenols, and also serves as a dicyclopentadienyl group, R 2 It will be part or all of. R in one molecule 2 In general formula (5), R has at least one dicyclopentadienyl group on average, and preferably 0.5 to 1 dicyclopentadienyl group per phenol ring. 2 The same is true for.

[0033] Examples of phenols that can be used as a raw material for the phenolic resin represented by the above general formula (5) include 2,6-dimethylphenol, 2,6-diethylphenol, 2,6-dipropylphenol, 2,6-diisopropylphenol, 2,6-di(n-butyl)phenol, 2,6-di(t-butyl)phenol, 2,6-dihexylphenol, 2,6-dicyclohexylphenol, and 2,6-diphenylphenol. From the viewpoints of availability and reactivity when formed into a cured product, 2,6-diphenylphenol or 2,6-dimethylphenol is preferred, and 2,6-dimethylphenol is particularly preferred.

[0034] The acid catalyst used in the reaction of phenols with dicyclopentadiene is a Lewis acid, specifically boron trifluoride compounds such as boron trifluoride, boron trifluoride-phenol complex, and boron trifluoride-ether complex, metal chlorides such as aluminum chloride, tin chloride, zinc chloride, titanium tetrachloride, and iron chloride, and organic sulfonic acids such as methanesulfonic acid, ethanesulfonic acid, and propanesulfonic acid, among which boron trifluoride-ether complex is preferred due to its ease of handling. The amount of the acid catalyst used in the case of boron trifluoride-ether complex is 0.001 to 20 parts by mass, preferably 0.5 to 10 parts by mass, per 100 parts by mass of dicyclopentadiene.

[0035] To confirm that the dicyclopentenyl group represented by formula (1b) or (1c) has been introduced into the phenolic resin represented by general formula (5), mass spectrometry and FT-IR measurement can be used.

[0036] When using mass spectrometry, electrospray ionization mass spectrometry (ESI-MS) or field desorption mass spectrometry (FD-MS) can be used. By subjecting a sample in which components with different nuclei numbers have been separated using GPC or the like to mass spectrometry, it is possible to confirm that the dicyclopentenyl group has been introduced.

[0037] When using the FT-IR measurement method, a sample dissolved in an organic solvent such as THF is applied to a KRS-5 cell, and the organic solvent is dried to obtain a cell with a thin film of the sample. When this cell is measured by FT-IR, a peak due to the CO stretching vibration of the phenol nucleus is observed at 1210 cm -1 Only when a dicyclopentenyl group is introduced, a peak due to the CH stretching vibration of the olefin part of the dicyclopentadiene skeleton appears around 3040 cm -1 It appears around 3040 cm. The baseline is a straight line connecting the start and end of the peak, and the peak height is the distance from the peak to the baseline. -1 Nearby peaks (A 3040 ) and 1210cm -1 Nearby peaks (A 1210 ) ratio (A 3040 / A 1210 The amount of dicyclopentenyl groups introduced can be quantified by the ratio. It has been confirmed that the higher the ratio, the better the physical properties. 3040 / A 1210 ) is 0.05 or more, more preferably 0.1 or more.

[0038] A suitable reaction method is to charge 2,6-disubstituted phenol and a catalyst in a reactor and then dropwise add dicyclopentadiene over a period of 1 to 10 hours.

[0039] The reaction temperature is preferably 50 to 200° C., more preferably 100 to 180° C., and further preferably 120 to 160° C. The reaction time is preferably 1 to 10 hours, more preferably 3 to 10 hours, and further preferably 4 to 8 hours.

[0040] After the reaction is completed, an alkali such as sodium hydroxide, potassium hydroxide, or calcium hydroxide is added to deactivate the catalyst. Then, a solvent such as aromatic hydrocarbons such as toluene or xylene, or ketones such as methyl ethyl ketone or methyl isobutyl ketone is added and dissolved, and the mixture is washed with water, and the solvent is recovered under reduced pressure to obtain the desired phenolic resin. It is preferable to react as much of the dicyclopentadiene as possible, and leave a portion of the 2,6-disubstituted phenols unreacted, preferably 10% or less, and recover them under reduced pressure.

[0041] In addition, during the reaction, solvents such as aromatic hydrocarbons such as benzene, toluene, xylene, etc., halogenated hydrocarbons such as chlorobenzene, dichlorobenzene, etc., and ethers such as ethylene glycol dimethyl ether, diethylene glycol dimethyl ether, etc. may be used as necessary for adjusting the viscosity, etc.

[0042] The epoxy resin represented by the general formula (4) can be advantageously obtained by reacting the above-mentioned phenolic resin with an epihalohydrin such as epichlorohydrin. This reaction is carried out according to a conventionally known method.

[0043] For example, an alkali metal hydroxide such as sodium hydroxide is added as a solid or concentrated aqueous solution to a mixture of a phenolic resin and an excess molar amount of epihalohydrin relative to the hydroxyl groups of the phenolic resin, and the mixture is reacted at a reaction temperature of 30 to 120°C for 0.5 to 10 hours; alternatively, a quaternary ammonium salt such as tetraethylammonium chloride is added as a catalyst to a phenolic resin and an excess molar amount of epihalohydrin, and the mixture is reacted at a temperature of 50 to 150°C for 1 to 5 hours to obtain a polyhalohydrin ether, to which an alkali metal hydroxide such as sodium hydroxide is added as a solid or concentrated aqueous solution, and the mixture is reacted at a temperature of 30 to 120°C for 1 to 10 hours.

[0044] In the above reaction, the amount of epihalohydrin used is 1 to 10 times, and preferably 2 to 5 times, the molar amount of the hydroxyl groups of the phenolic resin, and the amount of the alkali metal hydroxide used is 0.85 to 1.1 times the molar amount of the hydroxyl groups of the phenolic resin.

[0045] The epoxy resin obtained by these reactions contains unreacted epihalohydrin and alkali metal halide, so the desired epoxy resin can be obtained by removing the unreacted epihalohydrin from the reaction mixture by evaporation, and then removing the alkali metal halide by extraction with water, filtration, or the like.

[0046] The epoxy equivalent (g / eq.) of the dicyclopentadiene type epoxy resin is preferably 244-3,700, more preferably 260-2,000, and even more preferably 270-700.

[0047] The molecular weight distribution of dicyclopentadiene type epoxy resins can be changed by changing the ratio of phenolic resin and epihalohydrin used in the epoxidation reaction, and the closer the amount of epihalohydrin used to the hydroxyl groups of the phenolic resin is to an equimolar amount, the higher the molecular weight distribution, and the closer it is to 20 times the molar amount, the lower the molecular weight distribution. It is also possible to increase the molecular weight of the obtained epoxy resin by treating it again with phenolic resin.

[0048] A dicyclopentadiene type epoxy resin can be reacted with acrylic acid or methacrylic acid to produce an epoxy acrylate resin represented by the general formula (1). This epoxy acrylate resin can be made into a curable resin composition as described below, and can be made into a cured product.

[0049] The alkali-soluble resin represented by the general formula (2) of the present invention can be obtained from the epoxy acrylate resin represented by the general formula (1). In this sense, the epoxy acrylate resin represented by the general formula (1) is also an intermediate of the alkali-soluble resin represented by the general formula (2).

[0050] In the general formula (2), R 1 , R 2 and n are the same as those in the general formula (1), Y is an unsaturated bond-containing group represented by formula (2a), and L is a hydrogen atom or a carboxyl group-containing group represented by formula (3). Here, 50 mol % or more of L is a carboxyl group-containing group represented by formula (3). 3 is the same as formula (1a), where M represents a carboxylic acid residue having a valence of p+1, and p is 1 or 2. Here, the carboxylic acid residue is a group generated by removing a carboxyl group or an acid anhydride group from a di- or tri-valent carboxylic acid or a carboxylic acid anhydride. All of L may be carboxyl group-containing groups represented by formula (3), or may have both hydrogen atoms and carboxyl group-containing groups. The carboxyl group-containing groups are 50 mol% or more of the total L, preferably 70 to 100 mol%, more preferably 90 to 100 mol%, and even more preferably 100 mol%. The carboxyl group-containing groups are reactive with alkali, and therefore impart alkali solubility to the alkali-soluble resin or its polymerization reaction product (uncured product). By changing the ratio of the carboxyl group-containing groups in L, the alkali solubility can be adjusted and the alkali developability can be optimized. In addition, by changing the type of the carboxyl group-containing groups represented by formula (3), the resin properties including the alkali developability can be changed.

[0051] The alkali-soluble resin represented by general formula (2) can be obtained by reacting the hydroxyl group of the epoxy acrylate resin represented by general formula (1) with a carboxylic acid selected from dicarboxylic acids, tricarboxylic acids, or acid anhydrides thereof (acid monoanhydrides).

[0052] The carboxylic acids are exemplified as acid anhydrides since the reaction is often carried out using acid anhydrides. The carboxylic acid residue generated from the carboxylic acid 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 or tricarboxylic acids include acid monoanhydrides such as succinic acid, acetylsuccinic acid, adipic acid, azelaic acid, citramalic acid, malonic acid, glutaric acid, citric acid, tartaric acid, oxoglutaric acid, pimelic acid, sebacic acid, suberic acid, and diglycolic acid. Saturated cyclic hydrocarbon dicarboxylic or tricarboxylic acids include monoanhydrides of hexahydrophthalic acid, cyclobutanedicarboxylic acid, cyclopentanedicarboxylic acid, norbornanedicarboxylic acid, hexahydrotrimellitic acid, and the like. Unsaturated di- or tricarboxylic acids include monoanhydrides of maleic acid, itaconic acid, tetrahydrophthalic acid, methyl end methylene tetrahydrophthalic acid, chlorendic acid, and the like. Other dicarboxylic acids or tricarboxylic acids include acid anhydrides such as phthalic acid and trimellitic acid. Among these, acid anhydrides of succinic acid, itaconic acid, tetrahydrophthalic acid, hexahydrotrimellitic acid, phthalic acid, or trimellitic acid are preferred, and acid anhydrides of succinic acid, itaconic acid, or tetrahydrophthalic acid are more preferred. These carboxylic acids may be used alone or in combination of two or more.

[0053] The reaction temperature in synthesizing the alkali-soluble resin is preferably 20 to 120° C., more preferably 40 to 90° C. In this case, the molar ratio of the epoxy acrylate resin to the carboxylic acids is preferably selected so that the proportion of the carboxyl group-containing group in the above L is within the above range.

[0054] This alkali-soluble resin can be made into a photosensitive resin composition, which can be cured to give a cured product.

[0055] The epoxy acrylate resin or alkali-soluble resin of the present invention has, on average, two or more polymerizable unsaturated groups, and therefore can be made into a curable resin composition. When an epoxy acrylate resin is used, the resin does not have alkali developability, but when an alkali-soluble resin is used, the resin may have alkali developability. The curable resin composition of the present invention contains the epoxy acrylate resin of the present invention and a polymerization initiator. The photosensitive resin composition of the present invention contains the alkali-soluble resin of the present invention, a photopolymerizable monomer, and a photopolymerization initiator.

[0056] The curable resin composition of the present invention may contain a photopolymerization initiator or a radical polymerization initiator as an initiator, and may also contain a polyfunctional acrylate, etc. The resin component (epoxy acrylate resin and a component that becomes a resin after curing, not including a solvent) in the curable resin composition is preferably 30% by mass or more, more preferably 50% by mass or more, and even more preferably 70% by mass or more.

[0057] As the photopolymerization initiator, various known photopolymerization initiators can be used. For example, acetophenones such as acetophenone, 2,2-diethoxyacetophenone, p-dimethylacetophenone, p-dimethylaminopropiophenone, dichloroacetophenone, trichloroacetophenone, and pt-butylacetophenone, benzophenones such as benzophenone, 2-chlorobenzophenone, and p,p'-bisdimethylaminobenzophenone, benzoin ethers such as benzil, benzoin, benzoin methyl ether, benzoin isopropyl ether, and benzoin isobutyl ether, and 2-(o-chlorophenyl)acetophenones such as benzoin methyl ether, benzoin isopropyl ether, and benzoin isobutyl ether can be used. Biimidazole compounds such as 2-(o-chlorophenyl)-4,5-di(m-methoxyphenyl)biimidazole, 2-(o-fluorophenyl)-4,5-diphenylbiimidazole, 2-(o-methoxyphenyl)-4,5-diphenylbiimidazole, and 2,4,5-triarylbiimidazole; 2-trichloromethyl-5-styryl-1,3,4-oxadiazole, 2-trichloromethyl-5-(p-cyanostyryl)-1,3,4-oxadiazole, and 2-triaryl-5-(p-cyanostyryl)-1,3,4-oxadiazole; Halomethylthiazole compounds such as chloromethyl-5-(p-methoxystyryl)-1,3,4-oxadiazole, 2,4,6-tris(trichloromethyl)-1,3,5-triazine, 2-methyl-4,6-bis(trichloromethyl)-1,3,5-triazine, 2-phenyl-4,6-bis(trichloromethyl)-1,3,5-triazine, 2-(4-chlorophenyl)-4,6-bis(trichloromethyl)-1,3,5-triazine, 2-(4-methoxyphenyl)-4,6-bis(trichloromethyl)-1,3,5-triazine, Halomethyl-s-triazine compounds such as azine, 2-(4-methoxynaphthyl)-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, and 2-(4-methylthiostyryl)-4,6-bis(trichloromethyl)-1,3,5-triazine; 1,2-octanedione, 1-[4-(phenylthio)phenyl]-,o-Acyloxime compounds such as 2-(o-benzoyloxime), 1-(4-phenylsulfanylphenyl)butane-1,2-dione-2-oxime-o-benzoate, 1-(4-methylsulfanylphenyl)butane-1,2-dione-2-oxime-o-acetate, and 1-(4-methylsulfanylphenyl)butan-1-one oxime-o-acetate; benzyl dimethyl ketal, thioxanthone, 2-chlorothioxanthone, 2,4-diethylthioxanthone, 2-methylthioxanthone, 2-isopropyl ... Examples of the photopolymerization initiator include sulfur compounds such as isopropylthioxanthone, anthraquinones such as 2-ethylanthraquinone, octamethylanthraquinone, 1,2-benzanthraquinone, and 2,3-diphenylanthraquinone, organic peroxides such as azobisisobutylnitrile, benzoyl peroxide, and cumene peroxide, thiol compounds such as 2-mercaptobenzimidazole, 2-mercaptobenzoxazole, and 2-mercaptobenzothiazole, and tertiary amines such as triethanolamine and triethylamine. These photopolymerization initiators can be used alone or in combination of two or more.

[0058] Furthermore, these photopolymerization initiators and one or more known photosensitizers can be used simultaneously. Examples of the photosensitizer include Michler's ketone, N,N-dimethylaminobenzoic acid ethyl ester, N,N-dimethylaminobenzoic acid isoamyl ester, triethanolamine, triethylamine, etc. The amount of the photosensitizer used is preferably 0 to 20 parts by mass, more preferably 0.02 to 10 parts by mass, and even more preferably 0.05 to 2 parts by mass, relative to 100 parts by mass of the epoxy acrylate resin.

[0059] In order to carry out thermal polymerization, it is preferable to add a radical polymerization initiator, but it is not necessary to add it when only photocuring is carried out. Preferred radical polymerization initiators include, for example, known peroxides such as benzoyl peroxide, p-chlorobenzoyl peroxide, diisopropyl peroxycarbonate, di-2-ethylhexyl peroxycarbonate, and t-butyl peroxypiperate, and azo compounds such as 1,1'-azobiscyclohexane-1-carbonitrile, 2,2'-azobis-(2,4-dimethylvaleronitrile), 2,2'-azobis-(4-methoxy-2,4-dimethylvaleronitrile), 2,2'-azobis-(methylisobutyrate), α,α-azobis-(isobutyronitrile), and 4,4'-azobis-(4-cyanovaleric acid).

[0060] The amount of the polymerization initiator used is preferably from 0.01 to 100 parts by mass, more preferably from 0.5 to 40 parts by mass, and further preferably from 1 to 10 parts by mass, based on 100 parts by mass of the epoxy acrylate resin. The thermal polymerization initiator and the photopolymerization initiator may be used simultaneously, or either one of them may be used alone. The amount of the photopolymerization initiator used is preferably 0.01 to 100 parts by mass, more preferably 0.5 to 40 parts by mass, and even more preferably 1 to 10 parts by mass, relative to 100 parts by mass of the epoxy acrylate resin, and is usually 0.01 to 50 parts by mass, and preferably 1 to 20 parts by mass, relative to 100 parts by mass of the resin composition. The amount of the thermal polymerization initiator used is preferably 0.01 to 100 parts by mass, more preferably 0.02 to 60 parts by mass, and even more preferably 0.05 to 2 parts by mass, relative to 100 parts by mass of the epoxy acrylate resin, and is preferably 0.01 to 50 parts by mass, and more preferably 0.01 to 30 parts by mass, relative to 100 parts by mass of the curable resin composition. stomach.

[0061] The photosensitive resin composition of the present invention preferably contains 30 mass % or more, and more preferably 50 mass % or more, of the alkali-soluble resin represented by general formula (2) in the solid content excluding the solvent (the solid content includes monomers that become solid after curing).

[0062] In order to make the most of the characteristics of the photosensitive resin composition, it is preferable that the composition contains the following components (A) to (C) as essential components, and it is more preferable that the composition further contains component (D). (A) the alkali-soluble resin; (B) a photopolymerizable monomer having at least one polymerizable unsaturated group; (C) a photopolymerization initiator, (D) Epoxy resin

[0063] Examples of the photopolymerizable monomer as component (B) include monomers having a hydroxyl group, such as 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, and 2-ethylhexyl (meth)acrylate, as well as (meth)acrylic acid esters, such as 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, pentaerythritol 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 the molecules of the alkali-soluble resin, it is preferable to use a photopolymerizable monomer having two or more polymerizable unsaturated groups, and it is more preferable to use a photopolymerizable monomer having three or more polymerizable unsaturated groups. These compounds can be used alone or in combination of two or more.

[0064] The blending ratio [(A) / (B)] (mass ratio) of the (B) component and the (A) component is preferably 20 / 80 to 90 / 10, more preferably 40 / 60 to 80 / 20. Here, if the blending ratio of the alkali-soluble resin is low, the cured product after the photocuring reaction becomes brittle. In addition, the unexposed part has a low acid value of the coating film, so that the solubility in an alkaline developer is reduced, and the pattern edge is loose and not sharp. On the other hand, if the blending ratio of the alkali-soluble resin is higher than the above range, the proportion of photoreactive functional groups in the resin is reduced, and the formation of a crosslinked structure by the photocuring reaction may be insufficient. In addition, if the acid value of the resin component is too high, the exposed part has a high solubility in an alkaline developer, so that the formed pattern is likely to be narrower than the target line width, and the pattern is likely to be missing.

[0065] Examples of the photopolymerization initiator of component (C) include the same photopolymerization initiators as those mentioned in the description of the curable resin composition of the present invention. The amount of the (C) component added is preferably 0.1 to 10 parts by mass, more preferably 2 to 5 parts by mass, per 100 parts by mass of the total of the (A) and (B) components. If the amount of the photopolymerization initiator added is less than 0.1 parts by mass, sufficient sensitivity cannot be obtained, and if the amount of the photopolymerization initiator added is more than 10 parts by mass, the tapered shape (thickness direction shape of the developed pattern cross section) is not sharp and tends to have a trailing edge, resulting in halation. Furthermore, there is a risk of decomposition gas being generated when exposed to high temperatures in a later process.

[0066] Examples of the (D) epoxy resin include epoxy resins such as 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 epoxy resins, as well as compounds having at least one epoxy group such as phenyl glycidyl ether, p-butylphenol glycidyl ether, triglycidyl isocyanurate, diglycidyl isocyanurate, allyl glycidyl ether, and glycidyl methacrylate. When it is necessary to increase the crosslink density of the alkali-soluble resin, a compound having at least two epoxy groups is preferred.

[0067] When the (D) component is used, the amount of the component added is preferably in the range of 10 to 40 parts by mass per 100 parts by mass of the total of the (A) and (B) components. Here, one purpose of adding the epoxy resin is to reduce the amount of carboxyl groups remaining when the cured film is formed after patterning in order to increase the reliability of the cured film. In this case, if the amount of the epoxy resin used is less than 10 parts by mass, there is a risk that the moisture resistance reliability cannot be ensured when used as an insulating film. In addition, if the amount of the epoxy resin used is more than 40 parts by mass, the amount of photosensitive groups in the resin component in the photosensitive resin composition is reduced, and there is a risk that sufficient sensitivity for patterning cannot be obtained.

[0068] The photosensitive resin composition containing the above components (A) to (C) or the components (A) to (D) can be used by dissolving in a solvent or blending various additives as necessary. For example, when the photosensitive resin composition of the present invention is used for insulating material applications, it is preferable to use a solvent in addition to the above essential components. Examples of the solvent include alcohols such as methanol, ethanol, n-propanol, isopropanol, ethylene glycol, and propylene glycol; terpenes such as α- or β-terpineol; ketones such as acetone, methyl ethyl ketone, cyclohexanone, and N-methyl-2-pyrrolidone; aromatic hydrocarbons such as toluene, xylene, and tetramethylbenzene; cellosolve, methyl cellosolve, ethyl cellosolve, carbitol, methyl carbitol, ethyl carbitol, butyl carbitol, propylene glycol monomethyl ether ... These include glycol ethers such as ethyl ether, dipropylene glycol monomethyl ether, dipropylene glycol monoethyl ether, triethylene glycol monomethyl ether, triethylene glycol monoethyl ether, and acetates such as 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 ether acetate, etc. By dissolving and mixing these alone or in combination of two or more, a uniform solution-like composition can be obtained.

[0069] In addition, the photosensitive resin composition of the present invention may contain additives such as a curing accelerator, a thermal polymerization inhibitor, an antioxidant, a plasticizer, a leveling agent, an antifoaming agent, a coupling agent, and a surfactant, if necessary. Among these, the curing accelerator may be a known compound known as a curing accelerator, a curing catalyst, a latent curing agent, etc., which is usually applied to epoxy resins, and includes tertiary amines, quaternary ammonium salts, tertiary phosphines, quaternary phosphonium salts, boric acid esters, Lewis acids, organometallic compounds, imidazoles, diazabicyclo compounds, etc. Examples of thermal polymerization inhibitors and antioxidants include hydroquinone, hydroquinone monomethyl ether, pyrogallol, t-butylcatechol, phenothiazine, hindered phenol compounds, phosphorus-based heat stabilizers, etc. Examples of plasticizers include dibutyl phthalate, dioctyl phthalate, tricresyl phosphate, etc. Examples of fillers include glass fiber, silica, mica, alumina, etc. Examples of the defoaming agent and the leveling agent include silicone-based, fluorine-based, and acrylic compounds. Examples of the coupling agent include vinyltrimethoxysilane, 3-methacryloxypropyltrimethoxysilane, 3-(glycidyloxy)propyltrimethoxysilane, 3-isocyanatopropyltriethoxysilane, 3-aminopropyltriethoxysilane, 3-(phenylamino)propyltrimethoxysilane, and 3-ureidopropyltriethoxysilane. Examples of the surfactant include fluorine-based surfactants and silicone-based surfactants.

[0070] The photosensitive resin composition of the present invention contains the above components (A) to (D) in a total amount of 70% by mass or more, preferably 80% by mass or more, and more preferably 90% by mass or more, of the solid content excluding the solvent. The amount of the solvent varies depending on the target viscosity, but is preferably 10 to 80% by mass based on the total amount.

[0071] The coating film (cured product) of the present invention can be obtained, for example, by applying a solution of the photosensitive resin composition to a substrate or the like, drying the solvent, and curing by irradiating with light (including ultraviolet light, radiation, etc.). A coating film having a desired pattern can be obtained by providing areas exposed to light and areas not exposed to light using a photomask or the like, curing only the areas exposed to light, and dissolving the other areas with an alkaline solution.

[0072] Specific examples of each step of the film formation method by coating and drying the photosensitive resin composition include known methods such as solution immersion, spraying, and methods using a roller coater, land coater, slit coater, or spinner when coating the photosensitive resin composition on a substrate. After coating to a desired thickness by these methods, the solvent is removed (prebaked) to form a coating. Prebaking is performed by heating in an oven or hot plate, vacuum drying, or a combination of these. The heating temperature and heating time in prebaking can be appropriately selected depending on the solvent used, but it is preferable to perform, for example, at 80 to 120°C for 1 to 10 minutes.

[0073] Examples of radiation that can be used for exposure include visible light, ultraviolet light, far ultraviolet light, electron beams, g-rays, i-rays, and X-rays, and the wavelength of the radiation is preferably in the range of 250 to 450 nm. In addition, as a developer suitable for this alkaline development, for example, an aqueous solution of sodium carbonate, potassium carbonate, potassium hydroxide, diethanolamine, tetramethylammonium hydroxide, etc. can be used. These developers can be appropriately selected according to the characteristics of the resin layer, but it is also effective to add a surfactant as necessary. The development temperature is preferably 20 to 35°C, and fine images can be precisely formed using a commercially available developing machine, ultrasonic cleaner, etc. After the alkaline development, it is usually washed with water. As a development treatment method, a shower development method, a spray development method, a dip (immersion) development method, a puddle (liquid puddle) development method, etc. can be applied.

[0074] After the development, a heat treatment (post-baking) is performed at 180 to 250°C for 20 to 100 minutes. This post-baking is performed for the purpose of increasing 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-baking. The patterned coating film is formed through each process of the photolithography method. Then, polymerization or curing (both may be collectively referred to as curing) is completed by heat, to form a cured film such as an insulating film having a desired pattern. The curing temperature at this time is preferably 160 to 250°C. The cured product of the present invention may take various forms other than a cured film.

[0075] The photosensitive resin composition of the present invention has improved photocurability due to the large number of polymerizable unsaturated groups in one molecule of the component (A), and can increase the crosslink density after curing without increasing the amount of photopolymerization initiator. That is, when a thick film is irradiated with ultraviolet light or electron beams, the cured part is cured to the bottom, so that the difference in solubility in an alkaline developer between the exposed part and the unexposed part increases, improving the pattern dimensional stability, development margin, and pattern adhesion, and allowing a pattern to be formed with high resolution. And, even in the case of a thin film, the increased sensitivity can significantly improve the remaining film amount in the exposed part and suppress peeling during development.

[0076] The photosensitive composition of the present invention is extremely useful for applications such as solder resists, plating resists, and etching resists for producing circuit boards, insulating films for multilayering wiring boards on which semiconductor elements are mounted, semiconductor gate insulating films, and photosensitive adhesives (particularly adhesives that require heat adhesion performance even after pattern formation by photolithography). EXAMPLES

[0077] The present invention will be specifically described below based on examples, but the present invention is not limited thereto. In the examples, "parts" means parts by mass, and "%" means % by mass unless otherwise specified. In addition, the resins in these examples were evaluated as follows unless otherwise specified.

[0078] [Solid content concentration] The resin solution, photosensitive resin composition, etc. (approximately 1 g) was impregnated into a glass filter [mass: W0(g)] and precisely weighed [W1(g)]. The mass [W2(g)] after heating at 160°C for 2 hours was used to calculate the mass according to the following formula. Solids concentration (%) = 100 × (W2-W0) / (W1-W0)

[0079] [Acid value] The measurement was performed in accordance with JIS K 0070. Specifically, the resin solution was dissolved in dioxane and titrated with a 0.1N KOH aqueous solution using a potentiometric titrator "COM-1600" (manufactured by Hiranuma Sangyo Co., Ltd.), and the amount (mg) of KOH required per 1 g of solid content was taken as the acid value.

[0080] [Molecular weight] Measurement was performed using gel permeation chromatography (GPC) ("HLC-8220GPC" manufactured by Tosoh Corporation, columns: TSKgelSuperH2000 (2 columns) + TSKgelSuperH3000 (1 column) + TSKgelSuperH4000 (1 column) + TSKgelSuperH5000 (1 column) (all manufactured by Tosoh Corporation), solvent: tetrahydrofuran, temperature: 40°C, speed: 0.6 mL / min), and the value calculated in terms of standard polystyrene ("PS-Oligomer Kit" manufactured by Tosoh Corporation) was used as the weight average molecular weight (Mw).

[0081] [Dielectric constant, dielectric loss tangent] The value at 1 GHz was measured using the cavity resonance method (vector network analyzer (VNA) E8363B (Agilent Technologies), cavity resonator perturbation method dielectric constant measurement device (Kanto Electronics Application Development)) after storing the sample in a room at 23°C and 50% humidity for 24 hours after drying.

[0082] [Adhesion] At least 100 cross-cuts were made on the film of the cured film-attached glass substrate so as to form a grid pattern, and then a peeling test was carried out using cellophane tape, and the state of the grid patterns was visually evaluated. ◎: No peeling observed ○: Slight peeling of the coating film is observed △: Some peeling of the coating can be confirmed ×: The film is almost completely peeled off.

[0083] [Alkaline resistance] The glass substrate with the cured film was immersed in a mixed solution of 30 parts of 2-aminoethanol and 70 parts of glycol ether kept at 80°C, and after 10 minutes it was removed, washed with pure water, and dried to prepare a chemically-immersed sample, and the above-mentioned adhesion was evaluated.

[0084] [Acid resistance] The glass substrate with the cured film was immersed in a solution of aqua regia (hydrochloric acid:nitric acid = 7:3) kept at 50 °C, and after 10 minutes it was removed, washed with pure water, and dried to prepare a chemically immersed sample, and the above adhesion was evaluated.

[0085] The abbreviations for the materials used are as follows: E1: Epoxy resin obtained in Synthesis Example 1 E2: Epoxy resin obtained in Synthesis Example 2 E3: Phenol novolac type epoxy resin (Nippon Steel Chemical & Material Co., Ltd., YDPN-638, epoxy equivalent 177g / eq.) E4: Bisphenol A type liquid epoxy resin (Nippon Steel Chemical & Material Co., Ltd., YD-127, epoxy equivalent 182g / eq.) E5: Cresol novolac epoxy resin (Nippon Steel Chemical & Material Co., Ltd., YDCN-700-3, epoxy equivalent 203g / eq., softening point 73°C) THPA: 1,2,3,6-Tetrahydrophthalic anhydride TPP: Triphenylphosphine HQ: Hydroquinone TEAB: Tetraethylammonium bromide MIBK: Methyl isobutyl ketone PGMEA: Propylene glycol monomethyl ether acetate B1: Dipentaerythritol hexaacrylate C1: Photopolymerization initiator (BASF, Irgacure 184) C2: Photopolymerization initiator (4,4'-bis(dimethylamino)benzophenone (Michler's ketone))

[0086] Synthesis Example 1 970 parts of 2,6-xylenol and 14.5 parts of 47% BF3 ether complex were charged into a reactor equipped with a stirrer, a temperature control device, a nitrogen introducing device, a dropping device, and a reflux condenser, and heated to 70°C while stirring. While maintaining the same temperature, 300 parts of dicyclopentadiene (0.29 times the moles of 2,6-xylenol) were dropped over 2 hours. The mixture was further reacted at a temperature of 125 to 135°C for 6 hours, and 2.3 parts of calcium hydroxide were added. 4.6 parts of a 10% aqueous oxalic acid solution were further added. After that, the mixture was heated to 160°C for dehydration, and then heated to 200°C under a reduced pressure of 5mmHg to evaporate and remove the unreacted raw materials. 1000 parts of MIBK were added to dissolve the product, and 400 parts of 80°C hot water was added to wash it, and the lower layer water tank was separated and removed. Thereafter, the mixture was heated to 160°C under a reduced pressure of 5 mmHg to evaporate and remove the MIBK, yielding 540 parts of a reddish brown phenolic resin. The hydroxyl equivalent was 213, the softening point was 71°C, and the absorption ratio (A 3040 / A 1210) The mass spectrum was measured by ESI-MS (negative), and M-=253, 375, 507, and 629 were confirmed.

[0087] In a reaction vessel equipped with a stirrer, a temperature controller, a vacuum controller, a nitrogen inlet, a dropping device, and a reflux condenser, 250 parts of the obtained phenolic resin, 544 parts of epichlorohydrin, and 163 parts of diethylene glycol dimethyl ether were added and heated to 65°C. Under a reduced pressure of 125 mmHg, while maintaining the temperature at 63 to 67°C, 108 parts of a 49% aqueous sodium hydroxide solution were dropped over 4 hours. During this time, epichlorohydrin was azeotroped with water, and the water that flowed out was sequentially removed from the system. After the reaction was completed, epichlorohydrin was recovered under conditions of 5 mmHg and 180°C, and 948 parts of MIBK were added to dissolve the product. Then, 263 parts of water were added to dissolve the by-produced salt, and the solution was left to stand and the lower layer of saline was separated and removed. After neutralization with an aqueous phosphoric acid solution, the resin solution was washed with water until the washing water became neutral, and then filtered. The mixture was heated to 180℃ under a reduced pressure of 5mmHg to remove the MIBK, yielding 298 parts of reddish brown transparent 2,6-xylenol-dicyclopentadiene type epoxy resin (E1). The epoxy equivalent was 282, the total chlorine content was 980ppm, and the resin was semi-solid at room temperature.

[0088] Synthesis Example 2 In a reaction apparatus similar to that of Synthesis Example 1, 95.0 parts of 2,6-xylenol and 6.3 parts of 47% BF3 ether complex were charged and heated to 70°C while stirring. While maintaining the same temperature, 58.8 parts of dicyclopentadiene (0.56 times the moles of 2,6-xylenol) were added dropwise over 1 hour. After further reacting at a temperature of 115 to 125°C for 3 hours, 69.2 parts of dicyclopentadiene (0.67 times the moles of 2,6-xylenol) were added dropwise over 1 hour at the same temperature, and further reacted at a temperature of 115°C to 125°C for 2 hours. 1.0 part of calcium hydroxide was added. Furthermore, 2.0 parts of a 10% aqueous oxalic acid solution was added. After that, the mixture was heated to 160°C for dehydration, and then heated to 200°C under a reduced pressure of 5mmHg to evaporate and remove unreacted raw materials. The product was dissolved by adding 520 parts of MIBK, and then washed with 150 parts of 80°C hot water, and the lower layer of water was separated and removed. Then, the mixture was heated to 160°C under a reduced pressure of 5 mmHg to evaporate and remove the MIBK, yielding 221 parts of reddish brown phenolic resin. The hydroxyl equivalent was 377, the softening point was 102°C, and the absorption ratio (A 3040 / A 1210) was 0.18. Mass spectrum was measured by ESI-MS (negative), and M-=253, 375, 507, and 629 were confirmed.

[0089] In a reaction apparatus similar to that of Synthesis Example 1, 180 parts of the obtained phenolic resin, 221 parts of epichlorohydrin, and 33 parts of diethylene glycol dimethyl ether were added and heated to 65°C. Under a reduced pressure of 125 mmHg, while maintaining the temperature at 63 to 67°C, 39 parts of a 49% aqueous sodium hydroxide solution were dropped over 4 hours. During this time, epichlorohydrin was azeotroped with water, and the water that flowed out was sequentially removed from the system. After the reaction was completed, epichlorohydrin was recovered under conditions of 5 mmHg and 180°C, and 482 parts of MIBK were added to dissolve the product. Then, 146 parts of water were added to dissolve the by-produced salt, and the solution was left to stand and the lower layer of saline was separated and removed. After neutralization with an aqueous phosphoric acid solution, the resin solution was washed with water until the washing water became neutral, and filtered. The mixture was heated to 180℃ under a reduced pressure of 5mmHg to remove the MIBK, yielding 200 parts of a reddish-brown transparent 2,6-xylenol-dicyclopentadiene type epoxy resin (E2). The epoxy equivalent was 446, the total chlorine content was 431ppm, and the softening point was 91℃.

[0090] Example 1 In a reaction vessel equipped with a stirrer, a temperature controller, a reflux condenser, and an air introduction device, 282 parts of E1 were dissolved in 63 parts of PGMEA, and 72 parts of acrylic acid, 3.5 parts of TPP, and 0.1 parts of HQ were added. The mixture was reacted at 110°C for 8 hours while blowing in air, and then 293 parts of PGMEA was added to obtain a PGMEA solution of epoxy acrylate resin (R1). The solid content of the obtained resin solution was 50%.

[0091] The solvent was removed from the resulting resin solution by distillation under reduced pressure, and 100 parts of the resulting solid content was placed in a fluororesin mold, 1 part of dicumyl peroxide was added, and the mixture was cured by heating in an oven at 100°C for 30 minutes and at 170°C for 1 hour to obtain a cured product. A test piece with a thickness of 0.2 mm and a size of 0.2 cm x 10 cm was prepared from this cured product, and the relative dielectric constant and dielectric loss tangent were measured.

[0092] Example 2 In the same apparatus as in Example 1, 446 parts of E2 were dissolved in 97 parts of PGMEA, and 72 parts of acrylic acid, 3.5 parts of TPP, and 0.1 parts of HQ were added. The mixture was reacted at 110°C for 8 hours while blowing in air, and then 450 parts of PGMEA was added to obtain a PGMEA solution of epoxy acrylate resin (R2). The solid content of the obtained resin solution was 50%. The relative dielectric constant and dielectric loss tangent were measured in the same manner as in Example 1.

[0093] Comparative Example 1 In the same apparatus as in Example 1, 177 parts of E3 was dissolved in 44 parts of PGMEA, and 72 parts of acrylic acid, 3.5 parts of TPP, and 0.1 parts of HQ were added. The mixture was reacted at 110°C for 8 hours while blowing air into it, and then 208 parts of PGMEA was added to obtain a PGMEA solution of epoxy acrylate resin (HR1). The solid content of the obtained resin solution was 50%. The relative dielectric constant and dielectric loss tangent were measured in the same manner as in Example 1. The results are shown in Table 1.

[0094] [Table 1]

[0095] Example 3 In the same apparatus as in Example 1, 450 parts of a 50% PGMEA solution of R1, 95 parts of THPA, 1.8 parts of TEAB, and 38 parts of PGMEA were charged and stirred at 120 to 125° C. for 6 hours to obtain an alkali-soluble resin solution (A1). The solid content of the obtained resin solution was 55%.

[0096] A photosensitive resin composition was obtained by blending 53 parts of A1, 12.5 parts of B1, 1.3 parts of C1, 0.2 parts of C2, 6.3 parts of E5, and 28 parts of PGMEA.

[0097] The obtained photosensitive resin composition was applied to a 125 mm × 125 mm glass substrate using a spin coater so that the film thickness after post-baking would be 30 μm, and the substrate was pre-baked at 110 ° C. for 5 minutes to prepare a coated plate. 2The coated plate was irradiated with ultraviolet light of 365 nm wavelength from a high-pressure mercury lamp, and a photocuring reaction was performed by exposure to the entire surface. Next, the exposed coated plate was treated with a 0.8% tetramethylammonium hydroxide (TMAH) aqueous solution at 23°C for 60 seconds in a shower development process, and then washed with water spray. After that, a heat curing process was performed at 230°C for 30 minutes using a hot air dryer, and a glass substrate with a cured film was obtained.

[0098] Example 4 In the same apparatus as in Example 1, 450 parts of a 50% PGMEA solution of R2, 62 parts of THPA, 1.8 parts of TEAB, and 11 parts of PGMEA were charged and stirred at 120 to 125° C. for 6 hours to obtain an alkali-soluble resin solution (A2). The solid content of the obtained resin solution was 55%.

[0099] The same operations as in Example 3 were carried out except that A2 was used instead of A1, to obtain a photosensitive resin composition and a glass substrate with a cured film.

[0100] Comparative Example 2 In the same apparatus as in Example 1, 450 parts of a 50% PGMEA solution of HR1, 135 parts of THPA, 1.8 parts of TEAB, and 70 parts of PGMEA were charged and stirred at 120 to 125° C. for 6 hours to obtain an alkali-soluble resin solution (HA1). The solid content of the obtained resin solution was 55%.

[0101] The same operations as in Example 3 were carried out except that HA1 was used instead of A1, to obtain a photosensitive resin composition and a glass substrate with a cured film.

[0102] Comparative Example 3 In the same apparatus as in Example 1, 182 parts of E4 were dissolved in 45 parts of PGMEA, and 72 parts of acrylic acid, 3.5 parts of TPP, and 0.1 parts of HQ were added. The mixture was reacted at 110°C for 8 hours while blowing air into it, and then 212 parts of PGMEA were added to obtain a PGMEA solution of an epoxy acrylate resin. The solid content concentration of the obtained resin solution was 50%. 291 parts of the obtained resin solution, 4.0 parts of dimethylolpropionic acid, 11.8 parts of 1,6-hexanediol, and 104 parts of PGMEA were charged and heated to 45°C. Next, 61.8 parts of isophorone diisocyanate were dropped. After the dropwise addition, the mixture was stirred at 75 to 80°C for 6 hours. Furthermore, 21 parts of THPA was charged and stirred at 90 to 95°C for 6 hours to obtain an alkali-soluble resin solution (HA2). The solid content concentration of the obtained resin solution was 55%.

[0103] The same operations as in Example 3 were carried out except that HA2 was used instead of A1, to obtain a photosensitive resin composition and a glass substrate with a cured film.

[0104] The acid value (converted into solid content) and molecular weight (Mw) of the obtained resin solution were measured, and the results of adhesion, alkali resistance, and acid resistance tests were performed on the obtained glass substrate with the cured film are shown in Table 2.

[0105] [Table 2] [Industrial Applicability]

[0106] The curable resin composition, photosensitive resin composition, and cured product thereof of the present invention can be used as a solder resist, a plating resist, an etching resist for producing a circuit board, an insulating film for multilayering a wiring board on which a semiconductor element is mounted, a gate insulating film for a semiconductor, a photosensitive adhesive, and the like.

Claims

1. An epoxy acrylate resin represented by the following general formula (1): 【Chemistry 1】 Here, R １ each independently represents a hydrocarbon group having 1 to 8 carbon atoms; R ２ each independently represents a hydrogen atom or a dicyclopentenyl group, and at least one of them is a dicyclopentenyl group. X is an unsaturated bond-containing group represented by the above formula (1a), R ３ represents a hydrogen atom or a methyl group. n indicates the number of repetitions, the average value of which is 1 to 5.

2. A curable resin composition comprising the epoxy acrylate resin according to claim 1 and a polymerization initiator.

3. A cured product obtained by curing the curable resin composition according to claim 2.

4. An alkali-soluble resin represented by the following general formula (2) and having a carboxyl group and a polymerizable unsaturated group in the molecule: 【Chemistry 2】 Here, R １ each independently represents a hydrocarbon group having 1 to 8 carbon atoms; R ２ each independently represents a hydrogen atom or a dicyclopentenyl group, and at least one of them is a dicyclopentenyl group. R ３ represents a hydrogen atom or a methyl group. Y is an unsaturated bond-containing group represented by the above formula (2a), and R ３ represents a hydrogen atom or a methyl group. n indicates the number of repetitions, the average value of which is 1 to 5. L represents a hydrogen atom or a carboxyl-containing group represented by the above formula (3), and 50 mol % or more of L are carboxyl-containing groups. M represents a carboxylic acid residue having a valence of p+1, and p is 1 or 2.

5. 5. A photosensitive resin composition comprising the alkali-soluble resin according to claim 4, a photopolymerizable monomer having at least one polymerizable unsaturated group, and a photopolymerization initiator.

6. 6. The photosensitive resin composition according to claim 5, further comprising an epoxy resin.

7. 7. The photosensitive resin composition according to claim 5, further comprising 0.1 to 10 parts by mass of a photopolymerization initiator per 100 parts by mass of the total of the alkali-soluble resin and the photopolymerizable monomer.

8. 8. The photosensitive resin composition according to claim 6, further comprising 10 to 40 parts by mass of an epoxy resin per 100 parts by mass of the alkali-soluble resin and the photopolymerizable monomer combined.

9. A cured product obtained by curing the photosensitive resin composition according to any one of claims 5 to 8.

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