Curable polymer compound and resin composition containing the same

Abstract

To provide a curable polymer compound which is excellent in solvent solubility in a low boiling point solvent and is alkali-soluble and whose cured product has a low dielectric constant, a low dielectric loss tangent, and a high glass transition temperature.SOLUTION: The polymer compound is represented by the following formula (1) (where Y and Z each independently represent a divalent residue obtained by removing amino groups from an aromatic or aliphatic diamine compound; each X independently represents an N-(4-hydroxyphenyl)succinimide group, an N-(cyclohexa-1,5-diene-3,4-dione)succinimide group, or an acryloxyethylureido group; and m represents the average number of repeating units and is a real number of 0.1-20).SELECTED DRAWING: None

Description

[Technical field]

[0001] The present invention relates to a polymer compound which, when used in combination with a radical initiator, can undergo a thermal or photo-curing reaction, and since the uncured portion is soluble in an alkaline aqueous solution, can be patterned with an aqueous developer, and the cured product has excellent dielectric properties, heat resistance, and flexibility. [Background technology]

[0002] Aromatic bismaleimides are known as compounds with excellent heat resistance and dielectric properties, but they generally have poor solvent solubility and dissolve only in amide-based solvents such as N-methylpyrrolidone (NMP) and dimethylformamide (DMF), which have high boiling points and are toxic, so their use is limited in the electronic materials field, which uses glycol ether-based solvents such as propylene glycol monomethyl ether (PGME) and propylene glycol monomethyl ether acetate (PGMEA) with relatively low boiling points, and ketone-based solvents such as cyclopentanone and methyl ethyl ketone. In addition, the cured products are generally rigid and inflexible, making them difficult to use in film applications. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2006-241300 A [Patent Document 2] Japanese Patent Publication No. 61-243869 Summary of the Invention [Problem to be solved by the invention]

[0004] Patent Document 1 discloses a method for improving solvent solubility by subjecting aromatic bismaleimide to a Michael addition reaction with an aliphatic diamine to high molecular weight, but this polymer made of a bismaleimide compound and a diamine compound has a secondary amine remaining in the molecular structure, and since the secondary amine has high polarity, the dielectric loss tangent of the cured product is high, and is not suitable for high frequency applications that require a low preferential tangent. In addition, in the resist field, a photoinitiator is used to cause a curing reaction of a specific portion, and then development is generally performed with an alkaline aqueous solution such as an aqueous TMAH (tetramethylammonium hydroxide) solution, and alkali solubility is required for resist resins. As an alkali soluble resin used in the resist field, a resin obtained by adding acrylic acid to the epoxy group of a multifunctional epoxy resin as described in Patent Document 2 and reacting the resulting alcoholic hydroxyl group with an acid anhydride such as tetrahydrophthalic anhydride through half esterification is widely used, but these resins contain highly polar carboxylic acids in the resin, so naturally the dielectric loss tangent is high and they cannot be used for high frequency applications.

[0005] The present invention has been made in consideration of the above-mentioned points, and an object of the present invention is to provide a curable polymer compound that has excellent solvent solubility in low-boiling point solvents, is alkali-soluble, and has a low dielectric constant and dielectric tangent after curing, and a high glass transition temperature. [Means for solving the problem]

[0006] That is, the present invention relates to the following [1] to [5]. Note that in this application, "(Numerical value 1) to (Numerical value 2)" indicates that the upper and lower limits are included. [1] A polymer compound represented by the following formula (1):

[0007] [ka]

[0008] (In formula (1), Y and Z each independently represent a divalent residue of an aromatic or aliphatic diamine compound excluding an amino group, and X each independently represent any of the structures of formulae (2) to (4) below. m is the average number of repeating units and is a real number of 0.1 to 20.)

[0009] [ka]

[0010] (In formulas (2) to (4), * represents the bonding position to the nitrogen atom in formula (1). R represents a hydrogen atom or a methyl group.) [2] A resin composition comprising the polymer compound according to the above item [1] and a radical initiator. [3] The resin composition according to the above item [2], which contains a radical reactive monomer having one or more functional groups in one molecule. [4] The resin composition according to the above item [2], which contains a radically reactive polymer having two or more functional groups in one molecule. [5] A cured product of the resin composition described in any one of the preceding items [2] to [4]. Effect of the Invention

[0011] The polymer compound according to the present invention and a composition containing the same are soluble in low-boiling organic solvents and alkaline aqueous solutions, and can be cured by using a radical initiator in combination with the application of heat or light energy. The cured product of the composition can provide a polymer compound having excellent dielectric properties, heat resistance, and flexibility. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0012] As a result of intensive research, the present inventors have found that the above-mentioned problems can be solved by a polymer compound represented by the following formula (1), which is obtained by subjecting a diamine compound in an excess mole number to a bismaleimide and then subjecting some of the primary and secondary amino groups present in the polymer compound (intermediate 1) to a Michael addition reaction with 4-hydroxyphenylmaleimide, and then subjecting the remaining primary and secondary amino groups in the molecule to an addition reaction with an isocyanate group of a molecule containing an isocyanate group and a (meth)acrylic group in one molecule, and thus completed the present invention.

[0013] [ka]

[0014] (In formula (1), Y and Z each independently represent a divalent residue of an aromatic or aliphatic diamine compound excluding an amino group, and X each independently represent any of the structures of formulae (2) to (4) below. m is the average number of repeating units and is a real number of 0.1 to 20.)

[0015] [ka]

[0016] (In formulas (2) to (4), * represents the bonding position to the nitrogen atom in formula (1). R represents a hydrogen atom or a methyl group.)

[0017] The value of m in formula (1) can be determined by GPC (gel permeation chromatography) measurement. The structure of formula (2) or formula (3) in X in formula (1) is preferably 10 to 90 mol %, more preferably 20 to 80 mol %. If the structure of formula (2) or formula (3) is too little, the alkali solubility decreases, and if it is too much, the crosslink density during curing decreases, and the heat resistance decreases.

[0018] The structure of formula (3) is the oxidation of the structure of formula (2). Therefore, for example, by heating in the presence of oxygen for a certain period of time, such as by blowing air into the mixture, the phenolic hydroxyl group in the molecule is converted into a quinone structure, and the proportion of the structure of formula (3) increases. When the oxidation reaction is carried out in air, the temperature is preferably 150°C to 250°C, and the standing time is preferably 5 minutes to 2 hours. The proportion of the structure of formula (3) in the total amount of the structures of formula (2) and formula (3) is preferably 0 to 80 mol%, and more preferably 0 to 50 mol%, at the stage of the resin liquid. After curing and high-temperature oxidation, the proportion is preferably 20 to 100 mol%, and more preferably 50 to 100 mol%. At the stage of the resin liquid, the presence of a certain amount of the structure of formula (2) provides excellent alkali solubility, and after curing and high-temperature oxidation, the increase in the amount of formula (3) provides further improved dielectric properties and moisture absorption, thereby improving electrical reliability.

[0019] Examples of bismaleimides include 4,4'-diphenylmethane bismaleimide, bis-(3-ethyl-5-methyl-4-maleimidophenyl)methane, 2,2-bis-[4-(4-maleimidophenoxy)phenyl]propane, m-phenylene bismaleimide, 4-methyl-1,3-phenylene bismaleimide, 1,6'-bismaleimido-(2,2,4-trimethyl)hexane, and the like. In particular, bis-(3-ethyl-5-methyl-4-maleimidophenyl)methane is preferred in terms of solvent solubility.

[0020] Specific examples of the diamine compound include 1,2-diaminoethane, 1,3-diaminopropane, 1,4-diaminobutane, hexamethylenediamine, 1,8-diaminooctane, 1,10-diaminodecane, 1,12-diaminododecane, 4,4'-methylenebiscyclohexanediamine, 1,2-cyclohexanediamine, 1,3-cyclohexanediamine, 1,4-cyclohexanediamine, 1,3-bis(aminomethyl)cyclohexane, 1,4-bis(aminomethyl)cyclohexane, isophoronediamine, norbornenediamine, and dimers. Diamine, 3,3'-diamino-N-methyldipropylamine, diaminomaleonitrile, 1,3-diaminopentane, 9,10-diaminophenanthrene, 4,4'-diaminooctafluorobiphenyl, 3,5-diaminobenzoic acid, 3,7-diamino-2-methoxyfluorene, 4,4'-diaminobenzophenone, 3,4-diaminobenzophenone, 3,4-diaminotoluene, 2,6-diaminoanthraquinone, 2,6-diaminotoluene, 2,3-diaminotoluene, 1,8-diaminonaphthalene, 2,4-diaminotoluene, 2,5-diamino Aminotoluene, 1,4-diaminoanthraquinone, 1,5-diaminoanthraquinone, 1,5-diaminonaphthalene, 1,2-diaminoanthraquinone, 2,4-cumenediamine, 1,3-bisaminomethylbenzene, 1,3-bisaminomethylcyclohexane, 2-chloro-1,4-diaminobenzene, 1,4-diamino-2,5-dichlorobenzene, 1,4-diamino-2,5-dimethylbenzene, 4,4'-diamino-2,2'-bistrifluoromethylbiphenyl, bis(amino-3-chlorophenyl)ethane, bis(4-amino-3,5 -dimethylphenyl)methane, bis(4-amino-3,5-diethylphenyl)methane, 2,3-diaminonaphthalene, bis(4-amino-3-methylphenyl)methane, bis(4-amino-3-ethylphenyl)methane, 4,4'-diaminophenylsulfone, 3,3'-diaminophenylsulfone, 2,2-bis(4,(4-aminophenoxy)phenyl)sulfone, 2,2-bis(4-(3-aminophenoxy)phenyl)sulfone, 4,4'-oxydianiline, 4,4'-diaminodiphenylsulfide, 3,4'-oxydianiline, 2,2-bis(4-(4-aminophenoxy)phenyl)propane, 1,3-bis(4-aminophenoxy)benzene, 4,4'-bis(4-aminophenoxy)biphenyl, 4,4'-diamino-3,3'-dimethylbiphenyl, 4,4'-diamino-3,3'-dimethoxybiphenyl, 9,9-bis(4-aminophenyl)fluorene, 1,3-bis(4-aminophenoxy)-2,2-dimethylpropane, 1,3-bis(4-aminophenoxy)propane Examples of the amines include 1,4-bis(4-aminophenoxy)butane, 1,5-bis(4-aminophenoxy)butane, 2,3,5,6-tetramethyl-1,4-phenylenediamine; 3,3',5,5'-tetramethylbenzidine, 2,2-bis(4-aminophenyl)hexafluoropropane, m-xylylenediamine, p-xylylenediamine, bis(4-amino-3-methylcyclohexyl)methane, and 1,2-bis(2-aminoethoxy)ethane. These may be used alone or in combination of two or more.

[0021] Intermediate 1 of the compound of the present invention is represented by the following formula (5) and can be obtained by subjecting bismaleimide and a diamine compound to Michael addition.

[0022] [ka]

[0023] (In formula (5), Y and Z each independently represent a divalent residue of an aromatic or aliphatic diamine compound excluding an amino group. m is the average number of repeating units and is a real number of 0.1 to 20.)

[0024] The amount of raw material used in the above reaction is preferably 0.1 to 0.9 moles of bismaleimide per mole of diamine compound, more preferably 0.2 to 0.8 moles. A solvent is preferably used in the reaction, and examples of the solvent that can be used include toluene, xylene, methyl ethyl ketone, methyl isobutyl ketone, cyclopentanone, cyclohexanone, propylene glycol monomethyl ether, propylene glycol monomethyl ether acetate, dimethylformamide, dimethylacetamide, N-methylpyrrolidone, and γ-butyrolactone. The amount of the solvent used is preferably 0 to 300% by mass, more preferably 20 to 200% by mass, based on the solid content.

[0025] In order to rapidly advance the above reaction, it is preferable to use a catalyst. As the catalyst, a tertiary amine such as triethylamine or pyridine is preferable because it is easy to remove after the reaction. The amount of the catalyst used is preferably 10 to 200 mass % based on the solid content, and more preferably 20 to 150 mass %.

[0026] The ratio of bismaleimide to diamine compound is less than 1 mole per mole of diamine compound. The higher the ratio of bismaleimide, the higher the average molecular weight of the polymer intermediate, and the lower the ratio, the lower the average molecular weight, but both ends of the intermediate always become primary amines. The reaction temperature is usually 20 to 150°C, preferably 30 to 140°C, and the reaction time is usually 0.5 to 30 hours, preferably 1 to 20 hours. The end point of the reaction may be determined by GPC (gel permeation chromatography) when the peak of the raw material bismaleimide disappears and the molecular weight no longer increases from a certain value.

[0027] The polymer compound of the present invention can be obtained by subjecting some of the primary and secondary amino groups present in the intermediate 1 obtained above to a Michael addition reaction with 4-hydroxyphenylmaleimide, and then subjecting the remaining primary and secondary amino groups in the molecule to an addition reaction with an isocyanate group of a molecule containing an isocyanate group and a (meth)acrylic group in one molecule.

[0028] The amount of 4-hydroxyphenylmaleimide used is preferably 10 to 90%, more preferably 20 to 80%, of the total amount of primary and secondary amino groups present in intermediate 1. The reaction conditions can be the same as those for the Michael addition reaction between the above-mentioned bismaleimide and diamine compound. The end point of the reaction can be determined by the disappearance of the peak of 4-hydroxyphenylmaleimide by GPC (gel permeation chromatography) and the point at which the molecular weight no longer increases from a certain value.

[0029] Next, a compound containing an isocyanate group and a (meth)acrylic group in one molecule is added to the system to react with the amino group remaining in the system and the isocyanate group, thereby obtaining the polymer compound of the present invention.

[0030] Examples of compounds containing an isocyanate group and a (meth)acrylic group in one molecule include 2-isocyanatoethyl methacrylate (product name Karenz MOI, manufactured by Showa Denko KK), and 2-isocyanatoethyl acrylate (product name Karenz AOI, manufactured by Showa Denko KK).

[0031] The amount of the compound containing an isocyanate group and a (meth)acrylic group in one molecule is preferably the same equivalent as the total amount of primary amino groups and secondary amino groups remaining in the system. As a method for obtaining the polymer compound of the present invention, it is preferable to dilute the compound containing an isocyanate group and a (meth)acrylic group in one molecule in a solvent and dropwise add the diluted compound to the reaction solution after the Michael addition reaction of the above-mentioned 4-hydroxyphenylmaleimide while paying attention to the increase in reaction temperature. The reaction temperature is preferably 0 to 110°C, and the reaction time is preferably 30 minutes to 5 hours. After the reaction is completed, the catalyst is removed under reduced pressure with heating to obtain a solution of the polymer compound of the present invention.

[0032] The resin composition of the present invention contains the polymer compound of the present invention and a radical initiator. Preferred thermal radical initiators include peroxides such as benzoyl peroxide, cumene hydroperoxide, 2,5-dimethylhexane-2,5-dihydroperoxide, 2,5-dimethyl-2,5-di(t-butylperoxy)hexyne-3, di-t-butyl peroxide, t-butylcumyl peroxide, α,α-bis(t-butylperoxy-m-isopropyl)benzene, 2,5-dimethyl-2,5-di(t-butylperoxy)hexane, dicumyl peroxide, di-t-butylperoxyisophthalate, t-butylperoxybenzoate, 2,2-bis(t-butylperoxy)butane, 2,2-bis(t-butylperoxy)octane, 2,5-dimethyl-2,5-di(benzoylperoxy)hexane, di(trimethylsilyl)peroxide, and trimethylsilyltriphenylsilylperoxide.

[0033] Examples of preferred photoradical initiators include benzoin and its alkyl ethers such as benzoin, benzoin methyl ether, and benzoin ethyl ether; acetophenones such as acetophenone, 2,2-dimethoxy-2-phenylacetophenone, and 1,1-dichloroacetophenone; anthraquinones such as anthraquinone, 2-methylanthraquinone, 2-amylanthraquinone, 2-t-butylanthraquinone, and 1-chloroanthraquinone; thioxanthones such as 2,4-dimethylthioxanthone, 2,4-diisopropylthioxanthone, and 2-chlorothioxanthone; ketals such as acetophenone dimethyl ketal and benzyl dimethyl ketal; benzo Benzophenones such as phenone, 4,4'-bis(diethylamino)benzophenone, 4,4'-bis(dimethylamino)benzophenone; 2-methyl-1-[4-(methylthio)phenyl]-2-morpholino-propan-1-one and 2-benzyl-2-dimethylamino-1-(4-morpholinophenyl)-butanone-1; acylphosphine oxides and xanthones; oxime esters such as 1,2-octanedione, 1-[4-(phenylthio)phenyl]-, 2-(o-benzoyloxime), ethanone, 1-[9-ethyl-6-(2-methylbenzoyl)-9H-carbazol-3-yl]-, 1-(O-acetyloxime).

[0034] The content of the radical initiator in the resin composition of the present invention is usually 0.1 to 10 parts by mass, preferably 0.1 to 8 parts by mass, per 100 parts by mass of the polymer compound and the resin components such as the optional radical reactive monomer described below.

[0035] The resin composition of the present invention may be used in combination with a radical reactive monomer. By using a radical reactive monomer in combination, the reactivity of the resin composition of the present invention and the heat resistance of the cured product can be improved. The radical reactive monomer is preferably one having one or more functional groups, and specific examples thereof include acenaphthylene, ethylene glycol dimethacrylate, diethylene glycol dimethacrylate, triethylene glycol dimethacrylate, 1,4-butanediol dimethacrylate, neopentyl glycol dimethacrylate, 1,6-hexanediol dimethacrylate, 1,9-nonanediol dimethacrylate, glycerin dimethacrylate, 2-hydroxy-3-acryloyloxypropyl methacrylate, ethylene oxide adduct methacrylate of bisphenol A, trimethylolpropane trimethacrylate, tricyclodecane dimethanol dimethacrylate, glycerin dimethacrylate, trimethylolpropane trimethacrylate, ethoxylated isocyanuric acid triacrylate, ε-caprolactone modified tris-(2-acryloxyethyl)isocyanurate, pentaerythritol triacrylate, ditrimethylolpropane tetraacrylate, ethoxylated pentaerythritol tetraacrylate, pentaerythritol tetraacrylate, dipentaerythritol polyacrylate, dipentaerythritol hexaacrylate, triallyl isocyanurate, triallyl cyanurate, divinylbenzene, divinyl isophthalate, N-phenyl-maleimide, N-phenyl-methylmaleimide, N-phenyl-chloromaleimide amide, Np-chlorophenyl-maleimide, Np-methoxyphenyl-maleimide, Np-methylphenyl-maleimide, Np-nitrophenyl-maleimide, Np-phenoxyphenyl-maleimide, Np-phenylaminophenyl-maleimide, Np-phenoxycarbonylphenyl-maleimide, 1-maleimido-4-acetoxysuccinimide-benzene, 4-maleimido-4'-acetoxysuccinimide-diphenylmethane, 4-maleimido-4'-acetoxysuccinimide- Diphenyl ether, 4-maleimide-4'-acetamido-diphenyl ether, 2-maleimide-6-acetamido-pyridine, 4-maleimide-4'-acetamido-diphenylmethane, and Np-phenylcarbonylphenyl-maleimide N-ethylmaleimide, N-2,6-xylylmaleimide, N-cyclohexylmaleimide, N-2,3-xylylmaleimide, xylylmaleimide, 2,6-xylenemaleimide, and 4,4'-bismaleimidediphenylmethane. These radical reactive monomers may be used alone or in combination of two or more.

[0036] The resin composition of the present invention may be used in combination with a radical reactive polymer. By using a radical reactive polymer in combination, it is possible to improve the adhesiveness of the resin composition of the present invention and the heat resistance of the cured product. The radical reactive polymer is preferably one having two or more functional groups, and specific examples thereof include a copolymer of styrene and butadiene, a modified polyphenylene ether resin, an imide-extended bismaleimide, or a polymer represented by the following formula (6).

[0037] [ka]

[0038] (In formula (6), n is the average number of repeating units and is a real number from 1 to 20.)

[0039] The copolymer of styrene and butadiene may be a random copolymer (commonly known as SBR) or a block copolymer. It may also be a copolymer in which the double bonds derived from butadiene in the block copolymer are hydrogenated to form saturated hydrocarbons (commonly known as SEBS resin). The ratio of styrene to butadiene in the polymer is usually 10:90 to 90:10. The number average molecular weight is usually 1000 to 100,000. Specific examples of SBR products include Ricon 100, Ricon 181, and Ricon 184 from Cray Valley Corporation, and specific examples of SEBS resin products include the Tuftech series from Asahi Kasei Corporation and the G Polymer series from Kraton Corporation.

[0040] A preferred example of the modified polyphenylene ether resin is one having a methacryloyl group, an acryloyl group, or a vinyl group at both ends of the molecule and a number average molecular weight of 1000 to 10000. Specific examples include a compound represented by the following formula (7) having a methacryloyl group at both ends and a number average molecular weight of about 1700 (product name SA9000, manufactured by SABIC Japan LLC), and a compound represented by the following formula (8) having vinyl groups at both ends and a number average molecular weight of about 1200 or 2200 (product name OPE-2St 1200 or OPE-2St 2200, manufactured by Mitsubishi Gas Chemical Co., Inc.).

[0041] [ka]

[0042] [ka]

[0043] The imide-extended bismaleimide resin used in the present invention can be obtained by a known method described in, for example, Japanese Patent Publication No. 5328006. Specifically, the resin can be obtained by carrying out a dehydration condensation reaction of an aliphatic diamine and an aromatic or aliphatic tetracarboxylic dianhydride in an organic solvent using an acid catalyst in a molar ratio in which the aliphatic diamine is in excess, followed by dehydration condensation of amino groups present in the polymer terminals with maleic anhydride, and then removing the catalyst by washing with water.

[0044] Specific examples of aliphatic diamines include 1,10-diaminodecane; 1,12-diaminododecane; dimer diamine; 1,2-diamino-2-methylpropane; 1,2-diaminocyclohexane; 1,2-diaminopropane; 1,3-diaminopropane; 1,4-diaminobutane; 1,5-diaminopentane; 1,7-diaminoheptane; 1,8-diaminomenthane; 1,8-diaminooctane; 1,9-diaminononane; 3,3'-diamino-N-methyldipropylamine; diaminomaleonitrile; 1,3-diaminopentane; and 9,10-diaminophenanthrene, with dimer diamine being particularly preferred.

[0045] Specific examples of aromatic or aliphatic tetracarboxylic dianhydrides include pyromellitic anhydride, 1,2,3,4-cyclobutane tetracarboxylic dianhydride, 1,4,5,8-naphthalene tetracarboxylic dianhydride, 3,4,9,10-perylene tetracarboxylic dianhydride, bicyclo(2.2.2)oct-7-ene-2,3,5,6-tetracarboxylic dianhydride, diethylenetriaminepentaacetic dianhydride, ethylenediaminetetraacetic dianhydride, 3,3',4,4'-benzophenone tetracarboxylic dianhydride, 3,3',4,4'-biphenyl tetracarboxylic dianhydride, 4,4'-oxydiphthalic anhydride, 3,3',4,4'-diphenylsulfone tetracarboxylic dianhydride, 2,2'-bis(3,4-dicarboxyphenyl)hexafluoropropane dianhydride, and 4,4'-bisphenol A. Diphthalic anhydride, 5-(2,5-dioxytetrahydro)-3-methyl-3-cyclohexene-1,2-dicarboxylic anhydride, ethylene glycol bis(trimellitic anhydride), hydroquinone diphthalic anhydride, 1,2,3,4-cyclobutane tetracarboxylic dianhydride (CBDA), 1,2-dimethyl-1,2,3,4-cyclobutane tetracarboxylic dianhydride, 1,2,3,4-tetramethyl-1,2,3,4-cyclobutane tetracarboxylic dianhydride, 1,2,3,4-cyclopentane tetracarboxylic dianhydride, 1,2,4,5-cyclohexane tetracarboxylic dianhydride, 1,1'-bicyclohexane-3,3',4,4'-tetracarboxylic dianhydride Examples of suitable dianhydrides include tetracarboxylic acid-3,4:3',4'-dianhydride, 4-(2,5-dioxotetrahydrofuran-3-yl)-1,2,3,4-tetrahydronaphthalene-1,2-dicarboxylic acid anhydride, 5-(2,5-dioxotetrahydrofuryl)-3-methyl-3-cyclohexene-1,2-dicarboxylic acid dianhydride, bicyclo[2.2.2]oct-7-ene-2,3,5,6-tetracarboxylic acid dianhydride, 2,3,4,5-tetrahydrofuran tetracarboxylic acid dianhydride, and 3,5,6-tricarboxy-2-norbornane acetic acid dianhydride, but pyromellitic anhydride and 1,2,4,5-cyclohexane tetracarboxylic acid dianhydride are particularly preferred. A specific product name is BMI-3000 by Designer Molecules, Inc.

[0046] In addition, since the polymer compound of the present invention is alkali-soluble, it can be used in combination with a conventional alkali-soluble curable resin. A specific example of the alkali-soluble curable resin is a half ester obtained by adding acrylic acid to the epoxy group of a polyfunctional epoxy resin and reacting the resulting alcoholic hydroxyl group with a polybasic acid anhydride.

[0047] Examples of polyfunctional epoxy resins include bisphenol A type epoxy resins, bisphenol F type epoxy resins, phenol novolac type epoxy resins, cresol novolac type epoxy resins, aralkylphenol novolac type epoxy resins, biphenyl novolac type epoxy resins, triphenylmethane type epoxy resins, etc. Examples of the polybasic acid anhydrides include dibasic acid anhydrides such as maleic anhydride, succinic anhydride, itaconic anhydride, phthalic anhydride, tetrahydrophthalic anhydride, hexahydrophthalic anhydride, endomethylenetetrahydrophthalic anhydride, methyltetrahydrophthalic anhydride, and chlorendic anhydride, and polybasic acid anhydrides such as trimellitic anhydride, pyromellitic anhydride, benzophenonetetracarboxylic anhydride, and biphenyltetracarboxylic anhydride.

[0048] The resin composition of the present invention may be used in combination with an organic solvent. Specific examples of the organic solvent include aromatic solvents such as toluene and xylene, ether solvents such as diethylene glycol dimethyl ether, diethylene glycol diethyl ether, propylene glycol, propylene glycol monomethyl ether, propylene glycol monomethyl ether monoacetate, and propylene glycol monobutyl ether, ketone solvents such as methyl ethyl ketone, methyl isobutyl ketone, cyclopentanone, and cyclohexanone, lactones such as γ-butyrolactone and γ-valerolactone, amide solvents such as N-methylpyrrolidone (NMP), N,N-dimethylformamide (DMF), N,N-dimethylacetamide, and N,N-dimethylimidazolidinone, and sulfones such as tetramethylene sulfone. The content of the organic solvent in the resin composition of the present invention is usually 90% by mass or less, preferably 30 to 80% by mass in the resin composition.

[0049] The resin composition of the present invention may be used in combination with a polymerization inhibitor to improve storage stability. The polymerization inhibitor that can be used in combination is not particularly limited as long as it is a generally known one, and examples thereof include quinones such as hydroquinone, methylhydroquinone, p-benzoquinone, chloranil, and trimethylquinone, aromatic diols, and di-t-butylhydroxytoluene.

[0050] The resin composition of the present invention can be used by blending fillers and additives in amounts that do not impair the inherent performance, for the purpose of imparting desired performance depending on the application. The fillers may be in the form of fibers or powders, and examples of such fillers include silica, carbon black, alumina, talc, mica, glass beads, and glass hollow spheres.

[0051] The resin composition of the present invention can also be used in combination with a flame-retardant compound, an additive, and the like. These are not particularly limited as long as they are commonly used. For example, flame-retardant compounds include bromine compounds such as 4,4-dibromobiphenyl, phosphate esters, melamine phosphate, phosphorus-containing epoxy resins, nitrogen compounds such as melamine and benzoguanamine, oxazine ring-containing compounds, silicon-based compounds, and the like. Additives include ultraviolet absorbers, antioxidants, photopolymerization initiators, fluorescent brighteners, photosensitizers, dyes, pigments, thickeners, lubricants, defoamers, dispersants, leveling agents, gloss agents, and the like, and can be used in appropriate combination as desired.

[0052] The resin composition of the present invention can be used by coating or impregnating it on various substrates. For example, when a thermal radical initiator is used, it can be used as an interlayer insulating layer of a multilayer printed circuit board by coating it on a PET film, as a coverlay by coating it on a polyimide film, or as a resin-coated copper foil by coating and drying it on copper foil. It can also be used as a printed wiring board or a CFRP prepreg by impregnating it into glass cloth, glass paper, carbon fiber, various nonwoven fabrics, etc. Furthermore, by using a photoradical initiator, it is possible to develop a specific pattern by curing only the part irradiated with light of a specific wavelength and washing the other parts with an alkaline aqueous solution, and it can also be used as various resists such as a rewiring layer for semiconductors and a solder resist for printed circuit boards. It is also possible to convert the phenolic hydroxyl group in the molecule to a quinone structure and improve the dielectric properties and hygroscopicity by blowing air into the composition and heating it in the presence of oxygen for a certain period of time after thermal curing in a vacuum or in an inert gas such as nitrogen. The temperature when the oxidation reaction is carried out in air is preferably 150°C to 250°C, and the leaving time is preferably 5 minutes to 2 hours.

[0053] The interlayer insulating layer, coverlay, resin-coated copper foil, prepreg, and the like of the present invention can be heated and pressurized in a hot press or the like to form a cured product. EXAMPLES

[0054] The present invention will be described in more detail below with reference to examples and comparative examples. Unless otherwise specified, all parts are by weight. However, the present invention is not limited to these examples.

[0055] [Example 1 (Synthesis of polymer compound of the present invention)] A flask equipped with a thermometer, a condenser, a nitrogen gas inlet tube, and a stirrer was charged with 21.64 parts of dimer diamine (product name Priamine 1074, Croda), 10.62 parts of bis-(3-ethyl-5-methyl-4-maleimidophenyl)methane (product name BMI-70, KI Chemical Co., Ltd.), and 30 parts of propylene glycol monomethyl ether (PGME), and reacted for 8 hours at 100°C under a nitrogen atmosphere to obtain a PGME solution of intermediate 1 represented by the following formula (9). The value of n calculated from the number average molecular weight 2015 by GPC was 1.5.

[0056] [ka]

[0057] 15.12 parts of 4-hydroxyphenylmaleimide and 15 parts of PGME were added to the solution of intermediate 1, and the mixture was reacted at 100° C. under a nitrogen atmosphere for 10 hours. After confirming that the peak of 4-hydroxyphenylmaleimide disappeared by gel permeation chromatography (GPC), the temperature was lowered to room temperature, and 4.96 parts of 2-isocyanatoethyl methacrylate (product name Karenz MOI, manufactured by Showa Denko K.K.) was dissolved in 5 parts of PGME and added dropwise over 10 minutes. The mixture was reacted at room temperature for 1 hour to obtain a PGME solution of 52.34 parts of the polymer compound of the present invention having a structure represented by the following formula (10). Then, a small amount of PGME was added to adjust the solid content concentration to 50% by mass.

[0058] [ka]

[0059] (In formula (10), 71 mol % of X is represented by the following formula (11) or formula (12), and 29 mol % is represented by the following formula (13).)

[0060] [ka]

[0061] (In formulas (11) to (13), * represents the bonding position to the nitrogen atom in formula (10).)

[0062] [Comparative Example 1 (Synthesis of Comparative Polymer Compound)] A flask equipped with a thermometer, a cooling tube, a nitrogen gas inlet tube, and a stirrer was charged with 12.98 parts of dimer diamine (product name Priamine 1074 manufactured by Croda), 17.70 parts of bis-(3-ethyl-5-methyl-4-maleimidophenyl)methane (product name BMI-70 manufactured by Keiai Kasei Co., Ltd.), and 30 parts of propylene glycol monomethyl ether acetate (PGMEA), and reacted for 8 hours at 100°C under a nitrogen atmosphere to obtain 30.68 parts of a comparative resin represented by the following formula (14). The value of n calculated from the number average molecular weight of 1918 by GPC was 1.5. A small amount of PGMEA was then added to obtain a PGMEA solution with a solid content of 50% by mass.

[0063] [ka]

[0064] [Example 2, Comparative Example 2] (Alkaline solubility evaluation) 0.16 parts of each of the resin solutions obtained in Example 1 and Comparative Example 1 were placed in a 20 ml sample tube, and left to stand at 130°C under vacuum for 1 hour to completely evaporate the solvent. After that, 10 ml of a 2.38% aqueous solution of TMAH (tetramethylammonium hydroxide) was added, and the time until complete dissolution was measured.

[0065] [Table 1]

[0066] [Example 3, Comparative Example 3 (Preparation of Resin Composition)] To 10 parts of a PGME solution of the polymer compound 1 of the present invention obtained in Example 1 and 10 parts of a PGMEA solution of the comparative resin 1 obtained in Comparative Example 1, 0.1 parts of dicumyl peroxide as a radical initiator was added and mixed uniformly to obtain a resin composition 1 of the present invention and a comparative resin composition 2.

[0067] (Evaluation of dielectric properties and heat resistance of cured resin compositions) Resin compositions 1 and 2 obtained in Example 3 and Comparative Example 3 were applied to a thickness of 140 μm on the mirror surface of a copper foil having a thickness of 18 μm using an applicator, and the solvent was dried by heating at 130° C. for 10 minutes. The obtained film-like adhesive on the copper foil was heated and cured at 215° C. for 1 hour using a vacuum oven, and then immersed in an etching solution to remove the copper foil, thereby obtaining a cured product having a thickness of 70 μm that can be handled as a film. The obtained cured product was measured for the dielectric constant and dielectric loss tangent at 10 GHz by a cavity resonance method using a network analyzer 8719ET (manufactured by Agilent Technologies). The glass transition temperature of the test piece was also measured using a TMA (thermomechanical analyzer). The results are shown in Table 2.

[0068] (Evaluation of dielectric properties of cured resin composition 2) The sample whose dielectric properties had been measured in the above test was left in air at 215° C. for 1 hour, and then the dielectric properties and glass transition temperature were measured in the same manner as above.

[0069] [Table 2]

[0070] As described above, the polymer compound of the present invention is soluble in a low boiling point solvent and exhibits good solubility in an alkaline aqueous solution, and when the composition is cured using a radical initiator, it forms a flexible film and exhibits excellent dielectric properties and heat resistance. Furthermore, by leaving the composition in air at 215°C for 1 hour, the glass transition temperature was maintained and the dielectric properties became even better.

Claims

1. A polymer compound represented by the following formula (1): 【Chemistry 1】 (In formula (1), Y and Z each independently represent a divalent residue of an aromatic or aliphatic diamine compound excluding an amino group, and X each independently represent a structure represented by any one of the following formulae (2) to (4). m is the average number of repeating units and is a real number from 0.1 to 20.) 【Chemistry 2】 (In formulas (2) to (4), * represents the bonding position to the nitrogen atom in formula (1). R represents a hydrogen atom or a methyl group.)

2. A resin composition comprising the polymer compound according to claim 1 and a radical initiator.

3. The resin composition according to claim 2, further comprising a radical reactive monomer having one or more functional groups in one molecule.

4. The resin composition according to claim 2, which comprises a radically reactive polymer having two or more functional groups in one molecule.

5. A cured product of the resin composition according to any one of claims 2 to 4.

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