Benzoxazine compound, resin raw material composition containing same, curable resin composition, and cured product thereof

Abstract

The present invention addresses the problem of providing: a novel benzoxazine compound which can be stored for a long period of time even under room temperature conditions; a resin raw material composition containing the compound; a curable resin composition; and a cured product thereof. As a solution, a benzoxazine compound represented by general formula (1) is provided. [chemical formula 1] # imgabs0 # (In the formula, R1 each independently represents an alkylene group having 1 to 4 carbon atoms, and X represents a cycloalkylidene group having 5 to 20 carbon atoms.

Description

Technical Field

[0001] The present invention relates to a benzoxazine compound, a resin raw material composition containing the compound, a curable resin composition and a cured product thereof. Specifically, the present invention relates to a benzoxazine compound having a benzoxazine ring at both ends of a cycloalkylidene group and further having an allyl group, a resin raw material composition containing the compound, a curable resin composition and a cured product thereof. Background Art

[0002] Benzoxazine compounds are compounds synthesized by reacting phenols, amines, and formaldehyde. They are well known as thermosetting resin raw materials that cure by ring-opening polymerization of benzoxazine rings without generating volatile byproducts by heating, and are used as raw materials for molded bodies that can be used as insulating substrate materials, liquid crystal alignment agents, semiconductor sealing resin compositions, etc. In these applications, stability at high temperatures or heat resistance with excellent reliability is required.

[0003] On the other hand, there are still problems related to heat resistance, such as lack of heat resistance at 200° C. or higher. To improve this problem, a benzoxazine composition into which an allyl group is introduced has been reported (Patent Document 1).

[0004] Patent Literature Patent Document 1: Japanese Patent Application Publication No. 2003-286320 Summary of the invention Among benzoxazine monomers having an allyl group, the benzoxazine compound represented by formula (i) undergoes polymerization reaction even at room temperature, so its purity is reduced, and it has been found that it has a problem in terms of handling properties as a resin raw material.

[0005] [Chemistry 1]

[0006] An object of the present invention is to provide a novel benzoxazine compound having an allyl group which can be stored for a long period of time even at room temperature, a resin raw material composition containing the compound, a curable resin composition, and a cured product thereof.

[0007] The present inventors have conducted intensive studies to solve the above problems and have found that a benzoxazine compound using cycloalkylidene bisphenol as a raw material, having benzoxazine rings at both ends of the cycloalkylidene group and further having an allyl group can be stored for a long time even at room temperature, thereby completing the present invention.

[0008] The present invention is as follows.

[0009] 1. A benzoxazine compound, characterized in that it is represented by the general formula (1): [Chemistry 2]

[0010] In the formula, R1 each independently represents an alkylene group having 1 to 4 carbon atoms, and X represents a cycloalkylidene group having 5 to 20 carbon atoms.

[0011] 2. The benzoxazine compound according to 1., characterized in that X is cyclohexylidene, 3-methylcyclohexylidene, 4-methylcyclohexylidene, 3,3,5-trimethylcyclohexylidene or cyclododecylidene.

[0012] 3. A resin raw material composition, characterized in that it contains the benzoxazine compound described in 1.

[0013] 4. The resin raw material composition according to 3., wherein the content of the benzoxazine compound represented by the general formula (1) is in the range of 10 to 100 area % relative to all peak areas detected by gel permeation chromatography using a differential refractometer as a detector.

[0014] 5. A curable resin composition, characterized in that it contains the benzoxazine compound described in 1. or the resin raw material composition described in 3.

[0015] 6. The curable resin composition according to 5., characterized in that it contains the benzoxazine compound according to 1. or the resin raw material composition according to 3. and one or more selected from the group consisting of epoxy resins, benzoxazine compounds other than the benzoxazine compound represented by the general formula (1), phenolic resins and bismaleimide compounds.

[0016] 7. A cured product, characterized in that it is obtained by curing the curable resin composition described in 5.

[0017] The benzoxazine compound of the present invention and the resin raw material composition containing the same are very useful because they can be stored for a long period of time even at room temperature, compared to the conventionally known benzoxazine compound represented by the formula (i).

[0018] Furthermore, the curable resin composition comprising the benzoxazine compound of the present invention and the resin raw material composition containing the compound can obtain a cured product having excellent heat resistance and dielectric properties. Therefore, it is very useful as a resin material for prepregs, printed circuit boards, sealants for semiconductors or electronic components, electric and electronic molded parts, automobile parts, laminated materials, coatings, resist inks, etc. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 is a benzoxazine compound represented by formula (1-4) obtained in Example 1. 1 Spectrum obtained from H NMR analysis.

[0020] Figure 2 is a benzoxazine compound represented by formula (1-5) obtained in Example 2. 1 Spectrum obtained from H NMR analysis. DETAILED DESCRIPTION

[0021] <Benzoxazine compound of the present invention> The benzoxazine compound of the present invention is represented by the general formula (1).

[0022] [Chemistry 3]

[0023] (In the formula, R1 each independently represents an alkylene group having 1 to 4 carbon atoms, and X represents a cycloalkylidene group having 5 to 20 carbon atoms.) R1 in the general formula (1) is independently an alkylene group having 1 to 4 carbon atoms, preferably an alkylene group having 1 to 2 carbon atoms, more preferably a methylene group or a 1,2-ethylene group, and particularly preferably a methylene group.

[0024] X in the general formula (1) represents a cycloalkylidene group having 5 to 20 carbon atoms, and may contain an alkyl group as a branch. In this case, the number of carbon atoms of the alkyl group as a branch is also included in the number of carbon atoms of 5 to 20. The cycloalkylidene group preferably has 5 to 15 carbon atoms, more preferably has 6 to 12 carbon atoms, further preferably has 6 to 10 carbon atoms, and particularly preferably has 6 to 9 carbon atoms.

[0025] Specific examples of the cycloalkylidene group include a cyclopentylidene group (carbon number 5), a cyclohexylidene group (carbon number 6), a 3-methylcyclohexylidene group (carbon number 7), a 4-methylcyclohexylidene group (carbon number 7), a 3,3,5-trimethylcyclohexylidene group (carbon number 9), a cycloheptylidene group (carbon number 7), a bicyclo[2.2.1]heptane-2,2-diyl group (carbon number 7), a 1,7,7-trimethylbicyclo[2.2.1]heptane-2,2-diyl group (carbon number 10), a 4,7,7-trimethylbicyclo[2.2.1]heptane-2,2-diyl group (carbon number 10), a tricyclo[5.2.1.0 2,6] decane-8,8-diyl (carbon number 10), 2,2-adamantanylidene (carbon number 10), cyclododecylidene (carbon number 12), etc. Preferably, it is cyclohexylidene (carbon number 6), 3-methylcyclohexylidene (carbon number 7), 4-methylcyclohexylidene (carbon number 7), 3,3,5-trimethylcyclohexylidene (carbon number 9) or cyclododecylidene (carbon number 12), more preferably cyclohexylidene (carbon number 6), 3,3,5-trimethylcyclohexylidene (carbon number 9) or cyclododecylidene (carbon number 12), and particularly preferably 3,3,5-trimethylcyclohexylidene (carbon number 9).

[0026] In the present invention, specific examples of the benzoxazine compound represented by the general formula (1) include compounds represented by the following formulas (1-1) to (1-20). Among them, compounds (1-1) to (1-5) and compounds (1-11) to (1-15) are preferred, compounds (1-1), (1-4), (1-5), (1-11), (1-14) and (1-15) are more preferred, compounds (1-4), (1-5), (1-14) and (1-15) are further preferred, and compounds (1-4) and (1-14) are particularly preferred.

[0027] [Chemistry 4]

[0028] [Chemistry 5]

[0029] [Chemistry 6]

[0030] <Method for producing the compound of the present invention> The benzoxazine compound represented by the general formula (1) in the present invention is not particularly limited in terms of starting materials or production methods. For example, as shown in the following reaction formula, a bisphenol compound represented by the general formula (2) is subjected to a dehydration condensation reaction with an amine compound represented by the general formula (3) and formaldehyde to obtain the target benzoxazine compound represented by the general formula (1).

[0031] [Chemistry 7]

[0032] (In the formula, R1 and X have the same definitions as in the general formula (1).) In the above production method, a bisphenol compound represented by the general formula (2), an amine compound represented by the general formula (3), and formaldehyde are used as starting materials.

[0033] Specific examples of the bisphenol compound represented by the general formula (2) include bisphenol Z (1,1-bis(4-hydroxyphenyl)cyclohexane), 1,1-bis(4-hydroxyphenyl)-3-methylcyclohexane, 1,1-bis(4-hydroxyphenyl)-4-methylcyclohexane, 1,1-bis(4-hydroxyphenyl)-3,3,5-trimethylcyclohexane, 1,1-bis(4-hydroxyphenyl)cyclododecane, 2,2-bis(4-hydroxyphenyl)bicyclo[2.2.1]heptane, 2,2-bis(4-hydroxyphenyl)-1,7,7-trimethylbicyclo[2.2.1]heptane, 2,2-bis(4-hydroxyphenyl)-4,7,7-trimethylbicyclo[2.2.1]heptane, 4,4′-(tricyclo[5.2.1.0]hexane)-1,7,7-trimethylbicyclo[2.2.1]heptane, 4,4′-(tricyclo[5.2.1.0]hexane)-1,7,7-trimethylbicyclo[2.2.1]heptane, 4,4′-(tricyclo[5.2.1.0]hexane)-1,7,7-trimethylbicyclo[2.2.1]heptane, 4,4′-(tricyclo[5.2.1.0]hexane)-1,7,7-trimethylbicyclo[2.2.1]heptane. 2,6 ] decane-8,8-diyl) bisphenol, 2,2-bis(4-hydroxyphenyl)adamantane, etc. Among them, bisphenol Z (1,1-bis(4-hydroxyphenyl)cyclohexane), 1,1-bis(4-hydroxyphenyl)-3-methylcyclohexane, 1,1-bis(4-hydroxyphenyl)-4-methylcyclohexane, 1,1-bis(4-hydroxyphenyl)-3,3,5-trimethylcyclohexane or 1,1-bis(4-hydroxyphenyl)cyclododecane is preferred, 1,1-bis(4-hydroxyphenyl)-3,3,5-trimethylcyclohexane or 1,1-bis(4-hydroxyphenyl)cyclododecane is more preferred, and 1,1-bis(4-hydroxyphenyl)-3,3,5-trimethylcyclohexane or 1,1-bis(4-hydroxyphenyl)cyclododecane is particularly preferred.

[0034] Specific examples of the amine compound represented by the general formula (3) include allylamine, 3-butene-1-amine, and 4-butene-1-amine. Among them, allylamine is preferred.

[0035] The amine compound represented by the general formula (3) can also be used as a salt with an inorganic acid such as hydrochloric acid or sulfuric acid. In this case, the reaction can be carried out in the presence of an alkaline aqueous solution prepared by dissolving sodium hydroxide, potassium hydroxide, sodium carbonate, potassium carbonate, sodium hydrogen carbonate, potassium hydrogen carbonate or the like in water.

[0036] Specific examples of the formaldehydes include formaldehyde aqueous solution, trioxymethylene, and paraformaldehyde.

[0037] In the above production method, the amount of formaldehyde used is preferably in the range of 4.0 to 20.0 mol, more preferably 4.0 to 16.0 mol, and even more preferably 4.0 to 12.0 mol, per 1 mol of the bisphenol compound represented by the general formula (2).

[0038] In the above production method, the amount of the amine compound represented by the general formula (3) used is preferably in the range of 2.0 to 10.0 mol, more preferably in the range of 2.0 to 8.0 mol, and even more preferably in the range of 2.0 to 6.0 mol, based on 1 mol of the bisphenol compound represented by the general formula (2).

[0039] It is not particularly necessary to use a catalyst to promote the reaction, but an acid catalyst or a base catalyst may be used as required. At this time, as usable acid catalysts, concentrated hydrochloric acid, hydrogen chloride gas, trifluoroacetic acid, methanesulfonic acid, p-toluenesulfonic acid, benzoic acid and mixtures thereof, etc. may be cited, and as usable base catalysts, sodium hydroxide, sodium carbonate, triethylamine, triethanolamine and mixtures thereof, etc. may be cited, but are not limited thereto. Among them, p-toluenesulfonic acid and sodium hydroxide are preferred, and sodium hydroxide is further preferred.

[0040] The reaction is usually carried out in the presence of a solvent. As a solvent, there is no particular limitation as long as it does not hinder the reaction. Preferred examples include aromatic hydrocarbons with 6 to 9 carbon atoms such as toluene and xylene, aliphatic alkyls with 5 to 8 carbon atoms such as hexane, heptane, and cyclohexane, aliphatic esters with 3 to 6 carbon atoms such as methyl acetate, ethyl acetate, methyl propionate, and butyl acetate, and water. Among them, aromatic hydrocarbons with 6 to 9 carbon atoms and aliphatic esters with 3 to 6 carbon atoms are more preferred, and aliphatic esters with 3 to 6 carbon atoms are further preferred. These solvents can be used alone or in combination. In addition, the amount of the solvent used is not particularly limited as long as it does not hinder the reaction. Generally, it is preferably in the range of 200 to 400 parts by weight, and more preferably in the range of 250 to 300 parts by weight, relative to 100 parts by weight of the bisphenol compound represented by the general formula (2).

[0041] The reaction temperature is usually preferably in the range of 30 to 100°C, more preferably in the range of 30 to 80°C, and particularly preferably in the range of 40 to 70°C.

[0042] The reaction may be carried out under normal pressure, or under increased pressure or reduced pressure.

[0043] There is no limitation on the method for mixing the bisphenol compound represented by the general formula (2), formaldehydes and amine compounds represented by the general formula (3) as raw materials. For example, the following methods can be cited: (A) a method of mixing an amine compound represented by the general formula (3) into a mixture containing a bisphenol compound represented by the general formula (2) and formaldehydes to carry out a reaction; (B) a method of mixing a bisphenol compound represented by the general formula (2) into a mixture containing formaldehydes and an amine compound represented by the general formula (3). These mixtures may contain the above-mentioned solvent or catalyst, and the method for mixing the catalyst is also not limited. It is preferred to mix the catalyst before mixing the amine compound represented by the general formula (3).

[0044] In the production method of the present invention, there is no limitation on the method of mixing the raw materials and the remaining raw materials, but from the perspective of reaction selectivity and suppression of the formation of high molecular weight components as by-products, it is preferred to mix continuously or intermittently for example, for 10 minutes to 2 hours rather than mixing all at once.

[0045] As another embodiment, the step of discharging water from the raw materials or water generated in the reaction to the outside of the system may also be included. The step of removing the generated water from the reaction solution is not particularly limited, and can be performed by azeotropic distillation of the generated water with the solvent in the reaction solution. The generated water can be discharged to the outside of the reaction system using, for example, an isobaric dropping funnel equipped with a stopcock, a Dean condenser, a Dean-Stark apparatus, and the like.

[0046] As for the obtained reaction-finished mixture, the benzoxazine compound represented by the general formula (1) can be obtained from the mixture by a known method after the reaction. For example, the reaction mixture can be subjected to a deactivation treatment or water washing treatment of the catalyst used after the reaction, or the target product can be obtained in the form of a residual liquid by distilling off the residual raw materials or solvent from the reaction mixture. In addition, it is also conceivable to add the residual liquid to a poor solvent to obtain a precipitated target product, or to add a solvent to the reaction mixture for crystallization, and then obtain a powder or granular target product by filtering. The benzoxazine compound extracted by the above method can be made into a high-purity product by a conventional purification method such as washing with a solvent or water or recrystallization.

[0047] <Resin raw material composition containing a benzoxazine compound represented by the general formula (1)> The resin raw material composition of the present invention is characterized by containing a benzoxazine compound represented by the general formula (1), and can be obtained by distilling off the residual raw material or solvent from the reaction mixture. Alternatively, the target product can be precipitated by adding the residual liquid to a poor solvent, or a solvent can be added to the reaction mixture for crystallization, and then filtered to obtain a powder or granular resin raw material composition of the present invention. For example, by washing with a solvent or water or performing a conventional purification such as recrystallization, the resin raw material composition of the present invention having a high content of the benzoxazine compound represented by the general formula (1) can be obtained.

[0048] The resin raw material composition in the present invention may contain a compound produced as a byproduct in the reaction for producing the benzoxazine compound represented by the general formula (1). Examples of such byproducts include compounds having a higher molecular weight than the benzoxazine compound represented by the general formula (1).

[0049] In the resin raw material composition of the present invention, the content of the benzoxazine compound represented by the general formula (1) is not particularly limited. The content can be analyzed by gel permeation chromatography using a differential refractometer as a detector. The content is usually in the range of 10 to 100 area %, preferably in the range of 20 to 100 area %, more preferably in the range of 40 to 100 area %, and particularly preferably in the range of 60 to 100 area %, based on the areas of all peaks detected in the analysis.

[0050] <Curable resin composition comprising a benzoxazine compound represented by the general formula (1) or a resin raw material composition containing the same> The benzoxazine compound represented by the general formula (1) of the present invention or a resin raw material composition containing the compound can be used as a curable resin composition containing the compound as an essential component.

[0051] As one embodiment, there is a curable resin composition comprising a benzoxazine compound represented by the general formula (1) or a resin raw material composition containing the compound, an inorganic filler such as silicon oxide, aluminum oxide, magnesium oxide, boron nitride, aluminum nitride, silicon nitride, silicon carbide, hexagonal boron nitride, or a reinforcing fiber such as carbon fiber, glass fiber, organic fiber, boron fiber, steel fiber, aramid fiber, etc. mixed.

[0052] In another embodiment, there is a curable resin composition containing a benzoxazine compound represented by the general formula (1) or a resin raw material composition containing the compound as an essential component and containing other polymer materials.

[0053] The polymer material constituting the curable resin composition of the present invention is not particularly limited, and may contain epoxy resins, phenol resins, bismaleimide compounds, benzoxazine compounds other than the benzoxazine compound represented by the general formula (1), and respective raw materials.

[0054] Examples of the epoxy resin include o-cresol type epoxy resin, biphenyl type epoxy resin, biphenyl aralkyl type epoxy resin, naphthalene type epoxy resin, dihydroanthracene type epoxy resin, brominated novolac type epoxy resin, bisphenol A type epoxy resin, bisphenol F type epoxy resin, bisphenol S type epoxy resin, cycloalkylidene bisphenol type epoxy resin, phenol novolac type epoxy resin, cresol novolac type epoxy resin, resorcinol type epoxy resin, triphenylmethane type epoxy resin, dicyclopentadiene type epoxy resin, alicyclic epoxy resin, and the like.

[0055] Among these, from the viewpoint of heat resistance and dielectric properties of the obtained cured product, it is preferred to use at least one epoxy resin selected from the group consisting of cycloalkylidene bisphenol epoxy resins, dicyclopentadiene epoxy resins and alicyclic epoxy resins having a cyclic aliphatic structure.

[0056] Examples of commercially available products of the biphenyl epoxy resin include: “jER” YX4000H, “jER” YX4000, and “jER” YL6616 (manufactured by Mitsubishi Chemical Corporation).

[0057] As a commercial item of a biphenyl aralkyl type epoxy resin, NC-3000 (made by Nippon Kayaku Co., Ltd.) is mentioned, for example.

[0058] Examples of commercially available products of the naphthalene-based epoxy resin include “EPICLON” HP4032 (manufactured by DIC Corporation), NC-7000, and NC-7300 (manufactured by Nippon Kayaku Co., Ltd.).

[0059] Examples of commercially available products of bisphenol A epoxy resins include: jER 825, jER 826, jER 827, jER 828, and jER 834 (manufactured by Mitsubishi Chemical Corporation), EPICLON (registered trademark, hereinafter the same) 850 (manufactured by DIC Corporation), EPOTOHTO (registered trademark, hereinafter the same) YD-128 (manufactured by Nippon Steel Chemical Corporation), and DER-331 and DER-332 (manufactured by The Dow Chemical Company).

[0060] Examples of commercially available products of bisphenol F-type epoxy resins include: jER 806, jER 807, jER 1750, jER 4007P, and jER 4010P (manufactured by Mitsubishi Chemical Corporation), EPICLON 830 (manufactured by DIC Corporation), EPOTOHTO YD-170, EPOTOHTO YDF2001, and EPOTOHTO YDF2004 (manufactured by Nippon Steel Chemical Corporation).

[0061] As a bisphenol S type epoxy resin, EXA-1515 (made by DIC Corporation) is mentioned, for example.

[0062] Specific examples of the cycloalkylidene bisphenol epoxy resin include compounds represented by the following formula.

[0063] [Chemistry 8]

[0064] Examples of commercially available products of the phenol novolac epoxy resin include: jER 152, jER 154 (manufactured by Mitsubishi Chemical Corporation), EPICLON N-740, EPICLON N-770, and EPICLON N-775 (manufactured by DIC Corporation).

[0065] Examples of commercially available products of cresol novolac epoxy resins include EPICLON N-660, EPICLON N-665, EPICLON N-670, EPICLON N-673, and EPICLON N-695 (manufactured by DIC Corporation), and EOCN-1020, EOCN-102S, and EOCN-104S (manufactured by Nippon Kayaku Co., Ltd.).

[0066] As a commercial product of a resorcinol type epoxy resin, "DENACOL" (registered trademark, the same hereinafter) EX-201 (made by Nagase ChemteX Corporation) is mentioned, for example.

[0067] As a commercial item of a triphenylmethane type epoxy resin, TMH-574 (made by Sumitomo Chemical Co., Ltd.) is mentioned, for example.

[0068] As a dicyclopentadiene type epoxy resin, the compound represented by the following formula is mentioned, for example.

[0069] [Chemistry 9]

[0070] Examples of commercially available products of dicyclopentadiene epoxy resins include “Epiclon” HP7200, “Epiclon” HP7200L, and “Epiclon” HP7200H (manufactured by DIC Corporation), “Tactix” (registered trademark) 558 (manufactured by Huntsman Advanced Materials Co., Ltd.), and XD-1000 (manufactured by Nippon Kayaku Co., Ltd.).

[0071] Examples of the alicyclic epoxy resin include 3',4'-epoxycyclohexylmethyl 3,4-epoxycyclohexylcarboxylate, 3',4'-epoxycyclohexyloctyl 3,4-epoxycyclohexylcarboxylate, 1-methyl-4-(2-methyloxiranyl)-7-oxabicyclo[4.1.0]heptane, limonene dioxide, 1,2-epoxy-4-vinylcyclohexane, and compounds represented by the following formula.

[0072] [Chemistry 10]

[0073] Examples of commercially available products of 3',4'-epoxycyclohexylmethyl 3,4-epoxycyclohexylcarboxylate include: "CELLOXIDE" (registered trademark, hereinafter the same) 2021P (manufactured by Daicel Corporation) and CY179 (manufactured by Huntsman Advanced Materials).

[0074] Examples of the phenolic resin include novolac-type phenolic resins such as phenol novolac resins, cresol novolac resins, naphthol novolac resins, aminotriazine novolac resins, and triphenylmethane-type phenol novolac resins; modified phenolic resins such as terpene-modified phenolic resins and dicyclopentadiene-modified phenolic resins; aralkyl-type resins such as phenol aralkyl resins having a phenylene skeleton and / or a biphenylene skeleton, and naphthol aralkyl resins having a phenylene skeleton and / or a biphenylene skeleton; and resol-type phenolic resins.

[0075] As a bismaleimide compound, the raw material of the bismaleimide compound which has the following structure etc. are mentioned, for example.

[0076] [Chemistry 11]

[0077] Examples of benzoxazine compounds other than the benzoxazine compound represented by the general formula (1) include benzoxazine compounds having structures represented by the following general formulae (A) to (C).

[0078] [Chemistry 12]

[0079] (In the formula, Ra represents a divalent group having 1 to 30 carbon atoms, Rb each independently represents a monovalent group having 1 to 10 carbon atoms which may have a substituent, and n each independently represents 0 or 1.) [Chemistry 13]

[0080] (In the formula, Rc represents a divalent group having 1 to 30 carbon atoms, a direct bond, an oxygen atom, a sulfur atom, a carbonyl group or a sulfonyl group, and Rd each independently represents a monovalent group having 1 to 10 carbon atoms.) [Chemistry 14]

[0081] (In the formula, Re each independently represents a monovalent group having 1 to 10 carbon atoms, and m represents 0 or 1.) Ra in the benzoxazine compound having a structure represented by the general formula (A) represents a divalent group having 1 to 30 carbon atoms. Specific examples thereof include alkylene groups such as 1,2-ethylene, 1,4-butylene, and 1,6-hexylene; alkylene groups having a cyclic structure such as 1,4-cyclohexylene, biscyclopentadienylene, and adamantylene; and arylene groups such as 1,4-phenylene, 4,4'-biphenylene, diphenyl ether-4,4'-diyl, diphenyl ether-3,4'-diyl, benzophenone-4,4'-diyl, and diphenyl sulfone-4,4'-diyl.

[0082] Rb in the benzoxazine compound having a structure represented by the general formula (A) each independently represents a monovalent group having 1 to 10 carbon atoms. Specific examples thereof include alkyl groups such as methyl, ethyl, propyl, and butyl, alkenyl groups such as vinyl and allyl, alkynyl groups such as ethynyl and propargyl, and aryl groups such as phenyl and naphthyl. These groups may further have a substituent such as an alkoxy group having 1 to 4 carbon atoms, an acyl group having 1 to 4 carbon atoms, a halogen atom, a carboxyl group, a sulfo group, an allyloxy group, a hydroxyl group, and a thiol group.

[0083] Examples of the benzoxazine compound having a structure represented by the general formula (A) include Pd-type benzoxazine manufactured by Shikoku Chemicals Co., Ltd., and JBZ-OP100N and JBZ-BP100N manufactured by JFE Chemicals Co., Ltd.

[0084] Rc in the benzoxazine compound having a structure represented by the general formula (B) represents a divalent group having 1 to 30 carbon atoms, a direct bond, an oxygen atom, a sulfur atom, a carbonyl group, or a sulfonyl group. Examples of the divalent group having 1 to 30 carbon atoms include alkylene groups such as methylene, 1,2-ethylene, 1,4-butylene, and 1,6-hexylene; alkylene groups having a cyclic structure such as 1,4-cyclohexylene, dicyclopentadienylene, and adamantylene; and alkylidene groups such as ethylidene, propylidene, isopropylidene, butylidene, phenylethylidene, cyclopentylidene, cyclohexylidene, cycloheptylidene, cyclododecylidene, 3,3,5-trimethylcyclohexylidene, and fluorenylidene.

[0085] In the benzoxazine compound having a structure represented by the general formula (B), each Rd independently represents a monovalent group having 1 to 10 carbon atoms. Specific examples thereof include alkyl groups such as methyl, ethyl, propyl, and butyl, alkenyl groups such as vinyl and allyl (except for the case where Rc is a cycloalkylidene group having 5 to 20 carbon atoms), alkynyl groups such as ethynyl and propargyl, and aryl groups such as phenyl and naphthyl. These substituents may further have a substituent such as an alkoxy group having 1 to 4 carbon atoms, an acyl group having 1 to 4 carbon atoms, a halogen atom, a carboxyl group, a sulfo group, an allyloxy group, a hydroxyl group, and a thiol group.

[0086] Examples of the benzoxazine compound having a structure represented by the general formula (B) include Fa-type benzoxazine manufactured by Shikoku Chemicals Co., Ltd. and BS-BXZ manufactured by Konishi Chemical Industries, Ltd.

[0087] Re in the benzoxazine compound having a structure represented by the general formula (C) each independently represents a monovalent group having 1 to 10 carbon atoms. Specific examples thereof include alkyl groups such as methyl, ethyl, propyl, and butyl; alkenyl groups such as vinyl and allyl; alkynyl groups such as ethynyl and propargyl; and aryl groups such as phenyl and naphthyl. These substituents may further have a substituent such as an alkoxy group having 1 to 4 carbon atoms, an acyl group having 1 to 4 carbon atoms, a halogen atom, a carboxyl group, a sulfo group, an allyloxy group, a hydroxyl group, and a thiol group.

[0088] The curable resin composition of the present invention preferably comprises a benzoxazine compound represented by the general formula (1) or a resin raw material composition containing the compound, and at least one selected from the group consisting of an epoxy resin, a benzoxazine compound other than the benzoxazine compound represented by the general formula (1), a phenolic resin, and a bismaleimide compound.

[0089] In the curable resin composition of the present invention, the blending amount of the benzoxazine compound represented by the general formula (1) or a resin raw material composition containing the same and other polymer materials is in the range of 0.01 parts by weight to 100 parts by weight relative to 1 part by weight of the benzoxazine compound represented by the general formula (1) or a resin raw material composition containing the same.

[0090] The curable resin composition of the present invention is obtained by adding the benzoxazine compound represented by the general formula (1) or a resin raw material composition containing the compound to other polymer materials as required. The method of adding is not particularly limited, and a conventionally known method can be used. For example, the method includes: a method of adding during the synthesis or polymerization of the polymer material; a method of adding a resin composed of a polymer material to a molten molten resin, such as in a melt extrusion process; a method of impregnating a resin product composed of a polymer material, etc.

[0091] As for the curable resin composition of the present invention, if the composition contains water or residual solvent, bubbles will be generated during curing, so in order to avoid this situation, it is preferred to perform vacuum degassing as a pretreatment. The temperature of the vacuum degassing treatment is not particularly limited as long as it is a temperature that makes the resin composition of the present invention molten, but it is preferably carried out with 150°C as the upper limit because it will not be cured and is easy to degas. The pressure of the vacuum degassing treatment is not particularly limited, but low pressure (high degree of decompression) is preferred, and it can be carried out in air or in a nitrogen replacement environment. The vacuum degassing treatment is carried out until bubbles cannot be confirmed by visual observation.

[0092] The curable resin composition of the present invention can be mixed with inorganic fillers such as silicon oxide, aluminum oxide, magnesium oxide, boron nitride, aluminum nitride, silicon nitride, silicon carbide, hexagonal boron nitride, or reinforcing fibers such as carbon fiber, glass fiber, organic fiber, boron fiber, steel fiber, aramid fiber, etc., depending on the requirements of the application.

[0093] <Cured product obtained by curing the curable resin composition of the present invention> The cured product of the present invention is obtained by curing the curable resin composition of the present invention, wherein the curable resin composition contains the benzoxazine compound represented by the general formula (1) of the present invention or a resin raw material composition containing the compound as an essential component.

[0094] As a method for producing the cured product of the present invention, for example, there can be listed: a method of heating to a certain temperature to cure; a method of heating and dissolving, injecting into a mold, etc., and then heating the mold to cure and shape it; a method of injecting a molten material into a mold that has been heated in advance to cure it; a method of preparing a varnish containing the curable resin composition of the present invention and a solvent, removing the solvent and drying the mixture, placing the mixture in a mold, heating and curing it; a method of preparing a varnish, casting it on a support such as a polyimide or polyester film, a glass substrate, removing the solvent and drying it to obtain a film, and heating the film to cure it, etc.

[0095] The cured product of the present invention can be cured by ring-opening polymerization under the same curing conditions as conventional benzoxazine. The curing temperature is generally in the range of 70 to 300° C., preferably in the range of 100 to 280° C., more preferably in the range of 100 to 260° C., but in order to improve the mechanical properties of the obtained cured product, it is particularly preferably set to the range of 100 to 240° C. When curing is performed within this temperature range, the reaction time may be about 1 to 10 hours.

[0096] The resin composition of the present invention can be cured only by heat, but it is preferred to use a curing accelerator according to the components other than the benzoxazine compound represented by the general formula (1) or their content. The curing accelerator that can be used is not particularly limited, and examples thereof include: tertiary amines such as 1,8-diazabicyclo[5.4.0]undec-7-ene, triethylenediamine, tris(2,4,6-dimethylaminomethyl)phenol, imidazoles such as 2-ethyl-4-methylimidazole and 2-methylimidazole, triphenylphosphine, tetraphenylphosphonium bromide, tetraphenylphosphonium tetraphenylborate, phosphorus compounds such as tetra-n-butylphosphonium-О,О-diethyldithiophosphate, quaternary ammonium salts, organic metal salts and their derivatives. These can be used alone or in combination. Among these curing accelerators, tertiary amines, imidazoles and phosphorus compounds are preferably used.

[0097] The benzoxazine compound of the present invention, the resin raw material composition containing the compound, and the curable resin composition can be suitably used as a resin raw material for varnishes that can be applied to various substrates, prepregs impregnated with varnishes, copper-clad laminates, printed circuit boards, sealants for semiconductors or electronic components, electrical and electronic molded parts, automobile parts, laminated materials, coatings, and anti-corrosion inks, and the cured products can be suitably used as material resins for these. Among them, the cured products obtained using the benzoxazine compound of the present invention are useful as resin materials for prepregs, copper-clad laminates, printed circuit boards, sealants for semiconductors or electronic components, and electrical and electronic molded parts because they have excellent heat resistance and dielectric properties.

[0098] Example The present invention is further specifically described below by way of examples.

[0099] <Analysis method> 1. Liquid chromatography: LC Measuring device: High performance liquid chromatography Analyzer: Prominence UFLC (manufactured by Shimadzu Corporation) Pump: LC-20AD Column oven: CTO-20A Detector: SPD-20A Chromatographic column: HALO-C18 (inner diameter 3mm, length 75mm) Incubator temperature: 50℃ Flow rate: 0.7mL / min. Detection wavelength: 280nm Mobile phase: (A) 0.2 vol% acetic acid aqueous solution, (B) tetrahydrofuran Gradient conditions: (A) Volume % (time elapsed from the start of analysis) 20% (0min.) → 40% (10min.) → 60% (20min.) → 100% (37min.) → 100% (40min.) 2. Gel Permeation Chromatography: GPC Device: HLC-8320 / manufactured by Tosoh Corporation Detector: Differential Refractometer (RI) [Measurement conditions] Flow rate: 1mL / min. Eluent: Tetrahydrofuran Temperature: 40℃ Wavelength: 254nm Sampling interval: 100sec. Test sample: 10 mg of benzoxazine compound diluted 50 times with tetrahydrofuran Injection volume: 10 μL [Chromatographic column] (starting from the upper stream) Guard Column HXL-L+G4000HXL+G3000HXL+G2000HXL×2pcs (7.8mm ID×30cm, manufactured by Tosoh Corporation) 3. NMR analysis Measurement device: Fourier transform nuclear magnetic resonance AVANCE III HD 400 (manufactured by BRUKER) The sample was dissolved in deuterated chloroform and the 1 H-NMR spectrum.

[0100] 4. Determination of glass transition temperature (Tg) (dynamic viscoelasticity measurement (DMA)) Device: DMA850 / TA Instruments Japan Co., Ltd. Measurement conditions: 3-point bending Measuring temperature: 30~310℃ Measuring frequency: 1.0 (Hz) Sample size: (60mm×15mm×2mm) Heating rate: 1.0℃ / min. 5. Dielectric property evaluation The relative dielectric constant and dielectric loss tangent were measured for the films (sample size: width 1.5 mm, length 8.0 mm) produced in Examples and Comparative Examples using the following apparatus (sample size: width 1.5 mm, length 8.0 mm).

[0101] Measurement device: PNA network analyzer N522B (manufactured by Keysight Technologies, Inc.) Cavity resonator: CP531 for 10 GHz (manufactured by Kanto Denshi Application Development Co., Ltd.) [Measurement conditions] Test method: According to IEC 62180 (cavity resonator perturbation method) Test conditions: Frequency: 10GHz Number of measurements: n = 2 <Example 1> (Synthesis of the benzoxazine compound of the present invention represented by formula (1-4)) [Chemistry 15]

[0102] After adding 130 g (1.3 mol) of allylamine hydrochloride to a 2L four-necked flask equipped with a thermometer, a stirrer, a cooling tube, and a dropping funnel, 110 g (1.3 mol) of a 48% NaOH aqueous solution was slowly added over 5 minutes while stirring and confirming the temperature rise. After confirming that the pH of the water layer was about 9 to 10, 107 g (3.3 mol) of paraformaldehyde (purity: 92%) was added in multiple portions over 30 minutes. At this time, it was confirmed that the temperature of the reaction system rose from 30°C to 55°C. Then, the mixture was cooled with air while stirring, and after confirming that the temperature dropped to 30°C, it was stirred at 30°C for 1 hour.

[0103] After the stirring was completed, 586 g of ethyl acetate and 210 g of 1,1-bis(4-hydroxyphenyl)-3,3,5-trimethylcyclohexane were added to the flask. Then, the temperature of the liquid in the flask was raised to 55°C, and the reaction was carried out for 24 hours, 3 hours at 60°C, 5 hours at 65°C, and 1 hour at 70°C. As a result, it was confirmed that 1,1-bis(4-hydroxyphenyl)-3,3,5-trimethylcyclohexane disappeared. The temperature of the liquid in the flask was cooled to 40°C. The reaction liquid was analyzed by GPC, and the ratio of the benzoxazine compound present in the reaction liquid was 75 area%, and the remaining 25 area% was a compound with a higher molecular weight than the benzoxazine compound (high molecular weight component).

[0104] After 400 g of pure water was mixed with the reaction completed liquid, the mixture was stirred for 30 minutes, and after the mixture was allowed to stand and separation from the organic layer was confirmed, the aqueous layer was removed. This water washing operation was performed 6 times, and the pH of the aqueous layer was confirmed to be 7 to 8.

[0105] Then, the solvent was removed by distillation under reduced pressure at 40° C. After the solvent was removed, the mixture was cooled to obtain a non-fluid solid benzoxazine compound. The obtained benzoxazine compound was measured by GPC under the above-mentioned analysis conditions, and the purity was 70% by area, and the content of high molecular weight components was 30% by area.

[0106] The obtained distillation residue was heated to 90°C, flowed into a metal bucket, cooled to room temperature, and crushed to obtain 250 g of a yellow solid benzoxazine compound. The amount of solvent contained in the solid was 1.0% by weight. The yield was 78 mol% relative to the 1,1-bis(4-hydroxyphenyl)-3,3,5-trimethylcyclohexane used.

[0107] The obtained solid was 1 As a result of H-NMR analysis, peaks derived from 3,3,5-trimethylcyclohexylidene were observed at around 0.4 and 0.8-1.0 ppm, a peak derived from benzoxazine was observed at around 3.3-4.0 ppm, a peak derived from allylamine was observed at 4.8-5.2 ppm, and a peak derived from aromatics was observed at around 6.6-7.3 ppm. 1 The H-NMR spectrum is shown in Figure 1 From the analysis results, it was clear that it was the target compound, the benzoxazine compound represented by the formula (1-4).

[0108] <Example 2> (Synthesis of the benzoxazine compound of the present invention represented by formula (1-5)) [Chemistry 16]

[0109] After adding 120 g (1.2 mol) of allylamine hydrochloride to a 2L four-necked flask equipped with a thermometer, a stirrer, a cooling tube, and a dropping funnel, 101 g (1.2 mol) of a 48% NaOH aqueous solution was slowly added over 5 minutes while stirring and confirming the temperature rise. After confirming that the pH of the water layer was about 9 to 10, 96 g (3.0 mol) of paraformaldehyde (purity: 92%) was added several times over 1 hour. At this time, it was confirmed that the temperature of the reaction system rose from 30°C to 45°C. Then, the mixture was cooled with air while stirring, and after confirming that the temperature dropped to 30°C, it was stirred at 30°C for 1 hour.

[0110] After the stirring was completed, 584 g of ethyl acetate and 211 g of 1,1-bis(4-hydroxyphenyl)cyclododecane were added to the flask. Then, the temperature of the liquid in the flask was raised to 55°C and the reaction was carried out for 32 hours. Since 1,1-bis(4-hydroxyphenyl)cyclododecane remained, the reaction was further carried out at 60°C for 4 hours, and the disappearance of 1,1-bis(4-hydroxyphenyl)cyclododecane was confirmed. The temperature of the liquid in the flask was cooled to 40°C. The reaction solution was analyzed by GPC, and the proportion of benzoxazine compounds present in the reaction solution was 73% by area, and the remaining 27% by area was a compound with a higher molecular weight than the benzoxazine compound (high molecular weight component).

[0111] After 400 g of pure water was mixed with the reaction completed liquid, the mixture was stirred for 30 minutes, and after the mixture was allowed to stand and separation from the organic layer was confirmed, the aqueous layer was removed. This water washing operation was performed 6 times, and the pH of the aqueous layer was confirmed to be 7 to 8.

[0112] Then, the solvent was removed by distillation under reduced pressure at 40° C. After the solvent was removed, the mixture was cooled to obtain a non-fluid solid benzoxazine compound. The obtained benzoxazine compound was measured by GPC under the above-mentioned analysis conditions, and the purity was 70% by area, and the content of high molecular weight components was 30% by area.

[0113] The obtained distillation residue was heated to 90°C, poured into a metal bucket, cooled to room temperature, and crushed to obtain 308 g of a yellow solid benzoxazine compound. The amount of solvent contained in the solid was 9.9% by weight. The yield was 90 mol% relative to the 1,1-bis(4-hydroxyphenyl)cyclododecane used.

[0114] The obtained solid was 1 H-NMR analysis revealed peaks at 0.4 and 0.8-1.0 ppm derived from cyclododecane, at 3.3-4.0 ppm derived from benzoxazine, at 4.8-5.2 ppm derived from allylamine, and at 6.6-7.3 ppm derived from aromatics. 1 The H-NMR spectrum is shown in Figure 2 From the analysis results, it was clear that it was the target compound, the benzoxazine compound represented by the formula (1-5).

[0115] <Comparative Synthesis Example 1> (Synthesis of Benzoxazine Compound Represented by Formula (i)) [Chemistry 17]

[0116] 19.5 g of water and 19.5 g of NaOH (granular) were placed in a 500 mL four-necked flask equipped with a thermometer, a stirrer, and a cooling tube, and stirred. 19.5 g of allylamine hydrochloride was added to the alkaline solution, and stirred for 1 hour under a nitrogen environment. Then, 39.1 g of paraformaldehyde (purity: 92%) was added in small amounts and stirred for 5 hours. 93 g of ethyl acetate and 50 g of bisphenol F were added to the solution, and stirred at 30-40°C for 13 hours. During the process, 46 g of ethyl acetate was added due to increased viscosity. The disappearance of bisphenol F was confirmed by high performance liquid chromatography (HPLC). The reaction solution was analyzed by GPC, and the proportion of the benzoxazine compound represented by formula (i) present in the reaction solution was 65% by area, and the remaining 35% by area was a high molecular weight component.

[0117] After the reaction was completed, the salt and unreacted paraformaldehyde were removed by filtration, and the filtrate was washed with 50 mL of water for 5 times.

[0118] The washed filtrate was distilled under reduced pressure at 40° C. to remove the solvent. The pressure during distillation was gradually reduced to 1.4 kPa in the end.

[0119] After the solvent was distilled off and cooled, 55 g of the benzoxazine compound represented by formula (i) was obtained as a fluid oily substance. The amount of solvent contained in the oily substance was 1.0 wt %. The obtained oily substance was measured by GPC under the above-mentioned analysis conditions, and the purity was 61 area %, and the high molecular weight component was 39 area %.

[0120] (Evaluation of storage stability) 5 g of the benzoxazine compound obtained in Examples 1 and 2 and Comparative Synthesis Example 1 were placed in test tubes under the atmosphere and sealed, and the test tubes containing the samples were placed in a constant temperature bath and heated under the conditions of temperature and time shown in Table 1 below. The purity before and after heating was measured by GPC, and the change was calculated. The results are summarized in Table 1.

[0121] [Table 1]

[0122] As shown in Table 1, the purity of the benzoxazine compound represented by formula (i) obtained in Comparative Synthesis Example 1 decreased by 5.4 area % after storage at room temperature (30°C) for 7 days, and decreased by 29.7 area % after storage at a higher temperature of 50°C for 7 hours, compared with that before heating.

[0123] From this result, it is clear that the benzoxazine compound represented by the formula (i) undergoes polymerization reaction during storage, resulting in a decrease in purity, and therefore has a problem in terms of handling properties as a resin raw material.

[0124] On the other hand, the purity of the compound of formula (1-4) obtained in Example 1 of the present invention did not change at room temperature (30°C) and at a higher temperature of 50°C compared to before heating, and thus it was clear that it could be stored for a long period of time.

[0125] In addition, compared with before heating, the purity of the compound of formula (1-5) obtained in Example 2 did not change at a high temperature of 50°C, and the change was suppressed at room temperature (30°C), so it was clear that it can be stored for a long time.

[0126] <Example 3> 15 g of the compound of formula (1-4) obtained in Example 1, 16.5 g of dicyclopentadiene epoxy resin (manufactured by Nippon Kayaku Co., Ltd.: trade name "XD-1000"), 0.64 g of triphenylphosphine as a curing accelerator, and 40.0 g of methyl ethyl ketone were allowed to stand until completely dissolved. After preparing a varnish in which each component was completely dissolved, the solution was transferred to a bucket and dried in a ventilation device overnight, and then dried at 60°C for 4 to 5 hours in a vacuum dryer. Then, the film of the obtained composition was placed in a mold (φ100 mm press-in type) and cured using a hot press tester at 3 MPa at 100°C / 1 hour and 130°C / 2 hours. Then, a hot air circulation oven was used to perform post-curing treatment at 140°C / 2 hours, 150°C / 2 hours, 160°C / 2 hours, and 180°C / 2 hours to obtain a cured product.

[0127] <Comparative Synthesis Example 2> A cured product was obtained in the same manner as in Example 3 except that 10.0 g of a novolac curing agent (manufactured by AICA Industries, Ltd.: trade name “BRG-555”), 24.0 g of a dicyclopentadiene epoxy resin (manufactured by Nippon Kayaku Co., Ltd.: trade name “XD-1000”), 0.64 g of triphenylphosphine and 40.0 g of methyl ethyl ketone were used.

[0128] The glass transition temperature (Tg) and dielectric property evaluation were performed on the cured products obtained in Example 3 and Comparative Synthesis Example 2 under the above-mentioned analysis conditions. The results are summarized in Table 2.

[0129] [Table 2]

[0130] It was confirmed that the obtained cured product exhibited good heat resistance (Tg) and dielectric properties by using the compound of formula (1-4) obtained in Example 1 as a component of the curable resin.

[0131] As is apparent from the above, the benzoxazine compound of the present invention can be cured by mixing it with an epoxy resin or the like to obtain a cured product of a curable resin composition having excellent heat resistance and dielectric properties.

[0132] Therefore, it is very useful as a resin material such as a prepreg, a copper-clad laminate, a printed circuit board, a sealant for a semiconductor or an electronic component, an electric or electronic molded component, an automobile component, a laminated material, a coating material, and a resist ink.

Claims

1. A benzoxazine compound, characterized in that: It is expressed by the general formula (1): [Chemistry 1] In the formula, R1 each independently represents an alkylene group having 1 to 4 carbon atoms, and X represents a cycloalkylidene group having 5 to 20 carbon atoms.

2. The benzoxazine compound according to claim 1, characterized in that The X is cyclohexylidene, 3-methylcyclohexylidene, 4-methylcyclohexylidene, 3,3,5-trimethylcyclohexylidene or cyclododecylidene.

3. A resin raw material composition, characterized in that Contains the benzoxazine compound according to claim 1.

4. The resin raw material composition according to claim 3, characterized in that The content of the benzoxazine compound represented by the general formula (1) is in the range of 10 to 100 area % relative to the total peak area detected by gel permeation chromatography using a differential refractometer as a detector.

5. A curable resin composition, characterized in that A resin raw material composition comprising the benzoxazine compound according to claim 1 or the resin raw material composition according to claim 3.

6. The curable resin composition according to claim 5, characterized in that A benzoxazine compound according to claim 1 or a resin raw material composition according to claim 3, and at least one selected from the group consisting of an epoxy resin, a benzoxazine compound other than the benzoxazine compound represented by the general formula (1), a phenolic resin, and a bismaleimide compound.

7. A solidified product, characterized in that: The curable resin composition according to claim 5 is cured.

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