Novel benzoxazine compound, resin raw material composition containing the same, curable resin composition, and cured product thereof

Abstract

The present invention addresses the problem of providing: a novel benzoxazine compound that has excellent heat resistance, and can be cured under a low-temperature condition; a resin raw material composition containing the same; a curable resin composition; and a cured product thereof. As a solution, provided is a benzoxazine compound represented by general formula (1). (In the formula, R1 represents a hydrogen atom or an alkyl group having 1-6 carbon atoms, and R2 represents an alkylene group having 1-6 carbon atoms.)

Description

[Technical Field]

[0001] The present invention relates to a novel benzoxazine compound, a resin raw material composition containing the same, a curable resin composition, and a cured product thereof. More specifically, the present invention relates to a novel benzoxazine compound having benzoxazine rings at both ends of a methylene group and further having hydroxy groups, a resin raw material composition containing the same, a curable resin composition, and a cured product thereof. [Background technology]

[0002] Benzoxazine compounds are compounds synthesized by reacting phenols, amines, and formaldehyde, and are known as thermosetting resin raw materials that cure by ring-opening polymerization of the benzoxazine ring upon heating without producing volatile by-products, and are used as raw materials for molded articles that can be used as materials for insulating substrates, liquid crystal alignment agents, semiconductor encapsulation resin compositions, etc. For such applications, heat resistance with excellent stability and reliability at high temperatures is required. On the other hand, the curing temperature of benzoxazine compounds is usually relatively high, and in order to lower the polymerization temperature, catalysts, polymerization accelerators, and highly reactive benzoxazine compounds have been developed in recent years. Among these highly reactive benzoxazine compounds, benzoxazine compositions containing a hydroxyl functional group or a nitrogen-containing heterocycle have been reported that can be cured at a relatively low temperature in a short time by an environmentally friendly method (Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Special Publication No. 2011-530570 Summary of the Invention [Problem to be solved by the invention]

[0004] There is a demand for superior materials that can be cured at even lower temperatures in order to lower the temperature in the molding process of thermosetting resins, thereby improving efficiency by shortening heating and cooling times and saving energy, and to suppress thermal degradation of materials due to exposure to high temperatures during polymerization. An object of the present invention is to provide a novel benzoxazine compound that has excellent heat resistance and can be cured at low temperatures, a resin raw material composition containing the same, a curable resin composition, and a cured product thereof. [Means for solving the problem]

[0005] As a result of extensive research to solve the above-mentioned problems, the present inventors have found that a novel benzoxazine compound, which uses bisphenol F as a raw material, has benzoxazine rings at both ends of a methylene group, and further has hydroxy groups, has excellent heat resistance and can be cured at low temperatures, and have thus completed the present invention.

[0006] The present invention is as follows. 1. A benzoxazine compound represented by the following general formula (1): [ka] (In the formula, R1 represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms, and R2 represents an alkylene group having 1 to 6 carbon atoms.) 2. A resin raw material composition containing the benzoxazine compound according to 1. 3. A curable resin composition comprising the benzoxazine compound according to 1. or the resin raw material composition according to 2. 4. The curable resin composition according to 3., which contains the benzoxazine compound according to 1. or the resin raw material composition according to 2., and one or more compounds selected from the group consisting of epoxy resins, benzoxazine compounds other than the benzoxazine compound represented by general formula (1), phenolic resins, and bismaleimide compounds. 5. A cured product obtained by curing the curable resin composition according to 3. or 4. [Effects of the Invention]

[0007] The compound of the present invention can be cured at a lower temperature than Comparative Example Compound A having the following conventionally known chemical structure, and therefore can lower the temperature in the molding process of thermosetting resins, thereby enabling efficiency improvements through shortened heating and cooling times and energy savings, and is also very useful because it can be used on materials (substrates) that are sensitive to heat. [ka] Furthermore, the cured product of the compound of the present invention has extremely superior heat resistance compared to the cured product of the conventionally known comparative compound A, and is therefore a very useful material with excellent stability and reliability at high temperatures. The novel benzoxazine compound of the present invention, as well as a resin raw material composition, a curable resin composition, and a cured product thereof containing the same can be suitably used as a resin raw material for varnishes that can be applied to various substrates, prepregs impregnated with the varnish, printed circuit boards, sealants for electronic components, electrical and electronic molded components, automobile components, laminates, paints, resist inks, etc. DETAILED DESCRIPTION OF THE INVENTION

[0008] <Novel benzoxazine compound of the present invention> The novel benzoxazine compound of the present invention is represented by the following general formula (1). [ka] (In the formula, R1 represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms, and R2 represents an alkylene group having 1 to 6 carbon atoms.) R1 in general formula (1) is preferably a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, more preferably a hydrogen atom or an alkyl group having 1 carbon atom (methyl group), and particularly preferably a hydrogen atom. When R1 is a hydrogen atom, the embodiment is represented by the following general formula (1'). [ka] (wherein R2 is the same as in general formula (1)). When R1 bonded to the benzene ring in general formula (1) is an alkyl group (R1'), the bonding position is preferably ortho to the bonding position of the oxygen atom. This embodiment is represented by the following general formula (1"). [ka] (In the formula, R1′ represents an alkyl group, and R2 is the same as in general formula (1).) R2 in general formula (1) is preferably an alkylene group having 1 to 4 carbon atoms, more preferably an alkylene group having 1 or 2 carbon atoms, and particularly preferably an alkylene group having 2 carbon atoms (ethylene group). In general formula (1), the bonding positions between the central methylene group and the two benzoxazine rings are preferably ortho or para relative to the bonding position of the oxygen atom.

[0009] Specific examples of the novel benzoxazine compound represented by general formula (1) in the present invention include compounds (p-1) to (p-32) having the following chemical structures. Among these, compounds (p-1) to (p-20) are preferred, compounds (p-1) to (p-16) are more preferred, compounds (p-1) to (p-12) are even more preferred, and compounds (p-4) to (p-6) are particularly preferred. [ka] [ka] [ka] [ka]

[0010] <Method of producing the compound of the present invention> There are no particular limitations on the starting materials and production method for the novel benzoxazine compound represented by general formula (1) in the present invention. For example, as illustrated in the following reaction scheme, a production method can be mentioned in which a bisphenol compound represented by general formula (2), an aminoalcohol compound represented by general formula (3), and formaldehyde are subjected to a dehydration condensation reaction for cyclization to obtain the target novel benzoxazine compound represented by general formula (1). [ka] (wherein R1 and R2 are the same as in general formula (1)).

[0011] In the above production method, a bisphenol compound represented by the general formula (2), an aminoalcohol compound represented by the general formula (3), and formaldehydes are used as starting materials. Specific examples of the bisphenol compound represented by general formula (2) include bisphenol F (bis(2-hydroxyphenyl)methane, 2-hydroxyphenyl-4-hydroxyphenylmethane, bis(4-hydroxyphenyl)methane), bis(4-hydroxy-3-methylphenyl)methane, bis(2-hydroxy-5-methylphenyl)methane, bis(4-hydroxy-2-methylphenyl)methane, bis(2-hydroxy-6-methylphenyl)methane, and 2-hydroxy-6-methylphenyl-4-hydroxy-2-methyl-phenylmethane. Specific examples of the amino alcohol compound represented by general formula (3) include methanolamine, 2-aminoethanol, 3-amino-1-propanol, 1-amino-2-propanol, 4-amino-1-butanol, 2-amino-1-butanol, 4-amino-2-butanol, 5-amino-1-pentanol, 6-amino-1-hexanol, 7-amino-1-heptanol, and valinol. Among these, 2-aminoethanol is preferred. Specific examples of formaldehydes include aqueous formaldehyde solutions, 1,3,5-trioxane, and paraformaldehyde. In the above production method, the amount of formaldehyde used is preferably in the range of 4.0 to 20.0 mol, more preferably in the range of 4.0 to 16.0 mol, and even more preferably in the range of 4.0 to 12.0 mol, per 1 mol of the bisphenol compound represented by general formula (2). In the above production method, the amount of the aminoalcohol compound represented by 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, per 1 mol of the bisphenol compound represented by general formula (2).

[0012] Although a catalyst for promoting the reaction is not particularly required, an acid catalyst or a base catalyst can be used as necessary. In this case, examples of acid catalysts that can be used include concentrated hydrochloric acid, hydrochloric acid gas, trifluoroacetic acid, methanesulfonic acid, p-toluenesulfonic acid, benzoic acid, and mixtures thereof. Examples of base catalysts that can be used include, but are not limited to, sodium hydroxide, sodium carbonate, triethylamine, triethanolamine, and mixtures thereof. The reaction is usually carried out in the presence of a solvent. The solvent is not particularly limited as long as it does not inhibit the reaction, but preferred examples include toluene, xylene, ethyl acetate, butyl acetate, chloroform, dichloromethane, tetrahydrofuran, and dioxane. These solvents can be used alone or in combination. The amount of solvent used is not particularly limited as long as it does not interfere with the reaction, but is usually used in the range of 0.5 to 5 times by weight, preferably 1 to 3 times by weight, relative to the bisphenol compound represented by general formula (2). The reaction temperature is usually in the range of 10 to 150°C, preferably in the range of 10 to 120°C, more preferably in the range of 10 to 80°C, further preferably in the range of 20 to 70°C, and particularly preferably in the range of 20 to 60°C. The reaction may be carried out under normal pressure, or under increased pressure or reduced pressure. In another embodiment, the method may include a step of removing water derived from the raw materials or water generated during the reaction from the reaction system. The step of removing the generated water from the reaction solution is not particularly limited, and the generated water can be removed by azeotropically distilling the generated water with the solvent system in the reaction solution. The generated water can be removed from the reaction system using, for example, a pressure-equalizing dropping funnel equipped with a stopcock, a Dimroth condenser, a Dean-Stark apparatus, or the like.

[0013] After the reaction is completed, the resulting reaction mixture can be used to obtain the benzoxazine compound represented by general formula (1) by a known method. For example, the target product can be obtained as a residual liquid by distilling off the remaining raw materials and solvent from the reaction mixture after the reaction. Alternatively, the target product can be obtained by precipitating the residual liquid by adding a poor solvent, or by adding a solvent to the reaction mixture to cause crystallization and filtering the crystals to obtain a powder or granular target product. The benzoxazine compound isolated by the above method can be purified to a high purity by conventional purification means, such as washing with a solvent or water or recrystallization.

[0014] <Resin raw material composition containing a benzoxazine compound represented by general formula (1)> The resin raw material composition of the present invention is characterized by containing a benzoxazine compound represented by general formula (1) and can be obtained by distilling off the remaining raw materials and solvent from the aforementioned reaction mixture. Alternatively, the residual liquid can be added to a poor solvent to precipitate the target product, or a solvent can be added to the reaction mixture to cause crystallization, followed by filtration, to obtain a powder or granular resin raw material composition of the present invention. For example, the resin raw material composition of the present invention, which contains a high content of the benzoxazine compound represented by general formula (1), can be obtained by performing conventional purification such as washing with a solvent or water or recrystallization.

[0015] The resin raw material composition of the present invention may be produced by using a mixture of bisphenol compounds represented by general formula (2) in which the positions of methylene chains bonded to benzene rings are different in the reaction for producing the benzoxazine compound represented by general formula (1). In the bisphenol compound represented by the general formula (2) used, there is no particular limitation on the ratio of compounds having methylene chains bonded to benzene rings at different positions. To explain this using a specific example, when bisphenol F is used, a mixture of its positional isomers, i.e., bis(2-hydroxyphenyl)methane, 2-hydroxyphenyl-4-hydroxyphenylmethane, and bis(4-hydroxyphenyl)methane, can be used, and the ratio thereof is not particularly limited. Bisphenol F having a high ratio of bis(2-hydroxyphenyl)methane can be obtained, for example, by the method described in JP-A-08-245464, and bisphenol F having a high ratio of bis(4-hydroxyphenyl)methane can be obtained, for example, by the method described in JP-A-06-340565. When the benzoxazine compound of the present invention represented by general formula (1) is synthesized by the above-mentioned production method using a mixture of such positional isomers of bisphenol F and 2-aminoethanol as the aminoalcohol compound represented by general formula (3), a mixture of compounds (p-4), (p-5), and (p-6) can be obtained. In the bisphenol compound represented by general formula (2) used, the content of bisphenol (dinuclear compound) is not particularly limited, but is preferably 50% by weight or more, more preferably 70% by weight or more, even more preferably 85% by weight or more, and particularly preferably 89% by weight or more. Polynuclear compounds that are by-products in the production of bisphenol may also be contained.

[0016] The resin raw material composition of the present invention may contain a compound that is a by-product in the reaction for producing the benzoxazine compound represented by general formula (1). Examples of such by-products include compounds with a higher molecular weight than the benzoxazine compound represented by general formula (1). In the resin raw material composition of the present invention, the content of the benzoxazine compound represented by general formula (1) is not particularly limited, but the content can be analyzed by gel permeation chromatography using a differential refractometer as a detector, and is usually 10 to 100 area %, preferably 20 to 100 area %, more preferably 30 to 100 area %, and particularly preferably 40 to 100 area %, based on the area of ​​all peaks detected in such analysis.

[0017] <Curable resin composition containing a benzoxazine compound represented by general formula (1) or a resin raw material composition containing the same> The benzoxazine compound of the present invention represented by general formula (1) or a resin raw material composition containing the same can be used as a curable resin composition containing it as an essential component. One embodiment of the curable resin composition is a curable resin composition obtained by mixing a benzoxazine compound represented by general formula (1) or a resin raw material composition containing the compound with an inorganic filler such as silicon oxide, aluminum oxide, magnesium oxide, boron nitride, aluminum nitride, silicon nitride, silicon carbide, or hexagonal boron nitride, or a reinforcing fiber such as carbon fiber, glass fiber, organic fiber, boron fiber, steel fiber, or aramid fiber. Another embodiment is a curable resin composition containing, as an essential component, a benzoxazine compound represented by general formula (1) or a resin raw material composition containing the same, and containing other polymeric materials. The polymer material constituting the curable resin composition of the present invention is not particularly limited, but may contain an epoxy resin, a phenolic resin, a bismaleimide compound, a benzoxazine compound other than the benzoxazine compound represented by general formula (1), and raw materials for each of these. Examples of the epoxy resin include orthocresol type epoxy resin, biphenyl type epoxy resin, biphenyl aralkyl type epoxy resin, naphthalene type epoxy resin, anthracene dihydride type epoxy resin, and brominated novolac type epoxy resin. Examples of the phenolic resin include novolac-type phenolic resins such as phenol novolac resin, cresol novolac resin, naphthol novolac resin, aminotriazine novolac resin, and trisphenylmethane-type phenol novolac resin; modified phenolic resins such as terpene-modified phenolic resin and dicyclopentadiene-modified phenolic resin; aralkyl-type resins such as phenol aralkyl resins having a phenylene skeleton and / or biphenylene skeleton and naphthol aralkyl resins having a phenylene skeleton and / or biphenylene skeleton; and resol-type phenolic resins. Examples of the bismaleimide compound include raw materials for bismaleimide compounds having the following structure: [ka]

[0018] Examples of benzoxazine compounds other than the benzoxazine compound represented by general formula (1) include benzoxazine compounds having structures represented by the following general formulae (A) to (C). [ka] (In the formula, Ra represents a divalent group having 1 to 30 carbon atoms, each Rb represents a monovalent group having 1 to 10 carbon atoms which may have a substituent, and n represents 0 or 1.) [ka] (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 each Rd independently represents a monovalent group having 1 to 10 carbon atoms.) [ka] (In the formula, each Re independently represents a monovalent group having 1 to 10 carbon atoms, and m represents 0 or 1.)

[0019] In the benzoxazine compound having a structure represented by general formula (A), Ra 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 containing a cyclic structure such as 1,4-cyclohexylene, dicyclopentadienylene, and adamantylene, and arylene groups such as 1,4-phenylene, 4,4'-biphenylene, diphenylether-4,4'-diyl, diphenylether-3,4'-diyl, diphenylketone-4,4'-diyl, and diphenylsulfone-4,4'-diyl. In the benzoxazine compound having a structure represented by general formula (A), each Rb independently represents a monovalent group having 1 to 10 carbon atoms. Specific examples thereof include alkyl groups such as a methyl group, an ethyl group, a propyl group, and a butyl group; alkenyl groups such as a vinyl group and an allyl group; alkynyl groups such as an ethynyl group and a propargyl group; and aryl groups such as a phenyl group and a naphthyl group. 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 hydroxy group, or a thiol group. Examples of benzoxazine compounds having a structure represented by general formula (A) include Pd-type benzoxazine manufactured by Shikoku Chemicals Corporation, and JBZ-OP100N and JBZ-BP100N manufactured by JFE Chemical Corporation.

[0020] In the benzoxazine compound having a structure represented by general formula (B), 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. 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. In the benzoxazine compound having a structure represented by 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; 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 hydroxy group (excluding when Rc is methylene), or a thiol group. Examples of benzoxazine compounds having a structure represented by general formula (B) include Fa-type benzoxazine manufactured by Shikoku Chemical Industry Co., Ltd. and BS-BXZ manufactured by Konishi Chemical Industry Co., Ltd.

[0021] In the benzoxazine compound having a structure represented by general formula (C), each Re 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 hydroxy group, or a thiol group. In particular, the curable resin composition of the present invention preferably contains a benzoxazine compound represented by general formula (1) or a resin raw material composition containing the same, and one or more compounds selected from the group consisting of epoxy resins, benzoxazine compounds other than the benzoxazine compound represented by general formula (1), phenolic resins, and bismaleimide compounds.

[0022] In the curable resin composition of the present invention, the mixing amount of the benzoxazine compound represented by general formula (1) or the resin raw material composition containing it and the other polymeric materials is in the range of 0.01 to 100 parts by weight per 1 part by weight of the benzoxazine compound represented by general formula (1) or the resin raw material composition containing it. The curable resin composition of the present invention can be obtained by adding the benzoxazine compound represented by general formula (1) or a resin raw material composition containing the compound to the polymeric material, if necessary. The method of addition is not particularly limited, and any conventionally known method can be used. Examples of the method include adding the compound during synthesis or polymerization of the polymeric material, adding a resin made of the polymeric material to a molten resin in, for example, a melt extrusion process, and impregnating a resin product made of the polymeric material. If the curable resin composition of the present invention contains water or residual solvent, bubbles will form during curing. To prevent this, it is preferable to perform a vacuum degassing treatment as a pretreatment. The temperature of this vacuum degassing treatment is not particularly limited as long as it is a temperature at which the curable resin composition of the present invention is in a molten state. However, it is preferable to perform the treatment at an upper limit of 150°C because this temperature prevents curing and facilitates degassing. The pressure of the vacuum degassing treatment is not particularly limited, but a low pressure (high degree of vacuum) is preferable, and the treatment may be performed either in air or in a nitrogen-substituted atmosphere. The vacuum degassing treatment is performed until bubbles are no longer visible to the naked eye. The curable resin composition of the present invention can be used by mixing with inorganic fillers such as silicon oxide, aluminum oxide, magnesium oxide, boron nitride, aluminum nitride, silicon nitride, silicon carbide, and hexagonal boron nitride, or reinforcing fibers such as carbon fiber, glass fiber, organic fiber, boron fiber, steel fiber, and aramid fiber, depending on the application.

[0023] <Cured product obtained by curing the curable resin composition of the present invention> Next, the cured product of the present invention will be described. The cured product of the present invention can be obtained by curing the curable resin composition of the present invention, which contains, as an essential component, the benzoxazine compound represented by general formula (1) of the present invention or a resin raw material composition containing the same. Examples of methods for producing the cured product of the present invention include a method in which the material is heated to a predetermined temperature to be cured, a method in which the material is heated and melted and poured into a mold or the like, and the mold is further heated to be cured and molded, and a method in which the molten material is poured into a preheated mold and cured.

[0024] The cured product of the present invention can be cured by ring-opening polymerization under the same curing conditions as those for ordinary benzoxazine. The curing temperature is usually in the range of 150 to 300°C, preferably 170 to 280°C, and more preferably 170 to 260°C. In order to improve the mechanical properties of the resulting cured product, a temperature range of 170 to 240°C is particularly preferred. When curing is carried out within this temperature range, the reaction time may be approximately 1 to 10 hours. The production of the cured product may be carried out either in air or in an inert gas atmosphere such as nitrogen, but it is preferable to carry out the production in an inert gas atmosphere in order to prevent deterioration of the resulting cured product due to oxygen. Although the resin composition of the present invention can be cured by heat alone, depending on the components other than the benzoxazine compound represented by general formula (1) and their content, it may be preferable to use a curing accelerator. Usable curing accelerators are not particularly limited, but include, for example, tertiary amines such as 1,8-diaza-bicyclo[5.4.0]undecene-7, triethylenediamine, and tris(2,4,6-dimethylaminomethyl)phenol; imidazoles such as 2-ethyl-4-methylimidazole and 2-methylimidazole; phosphorus compounds such as triphenylphosphine, tetraphenylphosphonium bromide, tetraphenylphosphonium tetraphenylborate, and tetra-n-butylphosphonium-O,O-diethylphosphorodithioate; quaternary ammonium salts; organometallic salts; and derivatives thereof. These may be used alone or in combination. Among these curing accelerators, tertiary amines, imidazoles, and phosphorus compounds are preferred.

[0025] The benzoxazine compound of the present invention represented by general formula (1) has a lower curing temperature than the conventionally known Comparative Example Compound A, and therefore can be used to improve efficiency by shortening heating and cooling times and saving energy in the molding process of thermosetting resins, and is also very useful because it can be used on heat-sensitive materials (substrates). Furthermore, the cured product thereof has extremely superior heat resistance compared to the conventionally known Comparative Example Compound A, and is therefore a material with excellent stability and reliability at high temperatures, making it very useful. [Example]

[0026] The present invention will be explained in more detail below with reference to examples. <Analysis method> 1. Reaction solution composition and purity analysis (gel permeation chromatography: GPC) The purity of each synthesized benzoxazine compound was expressed as the area percentage value of the benzoxazine compound obtained by this analysis. Device: HLC-8320 / Tosoh Corporation Detector: Differential refractometer (RI) [Measurement conditions] Flow rate: 1mL / min Eluent: tetrahydrofuran Temperature: 40℃ Wavelength: 254nm Measurement sample: 1 g of a composition containing a benzoxazine compound was diluted 200 times with tetrahydrofuran. 2. Curing Characterization The curing properties of the various synthesized benzoxazine compounds were evaluated by differential scanning calorimetry (DSC) under the following operating conditions: The exothermic peak temperature was taken as the curing temperature. [Measurement conditions] Equipment: DSC7020 / Hitachi High-Tech Science Co., Ltd. Heating rate: 10℃ / min Measurement temperature range: 30 to 400°C Measurement atmosphere: Nitrogen 50mL / min Measurement sample: 3 mg of various synthesized benzoxazine compounds 3. Heat resistance evaluation (5% weight loss temperature measurement) The heat resistance of the synthesized benzoxazine compounds was evaluated by curing them at 250°C (curing time: 1 hour, heating rate: 10°C / min), cooling them to room temperature (cooling rate: 10°C / min), and then measuring the 5% weight loss temperature by thermogravimetry (TG) under the following operating conditions. [Measurement conditions] Equipment: DTG-60A / Shimadzu Corporation Temperature: 30 → 500℃ (heating rate 10℃ / min) Measurement atmosphere: Open, nitrogen 50mL / min Measurement sample: 10 mg of various synthesized benzoxazine compounds 4. Heat resistance evaluation of cured benzoxazine compounds The heat resistance of the cured products of the various synthesized benzoxazine compounds was evaluated by measuring the glass transition temperature (Tg) by dynamic viscoelasticity measurement under the following operating conditions. [Measurement conditions] Device: DMA Q800 (manufactured by TA Instruments Japan Co., Ltd.) Jig: Dual cantilever Frequency: 1Hz Temperature: 30→250℃ (2℃ / min) Measurement sample: Test piece obtained by the method described below

[0027] Example 1 (Synthesis of the compound of the present invention represented by the following chemical formula) [ka] A 1 L four-neck flask equipped with a thermometer, stirrer, condenser, and dropping funnel was charged with 97 g (0.49 mol) of bisphenol F (dinuclear content 90.1 wt%, isomer ratio of which is: bis(2-hydroxyphenyl)methane 18.8 wt%, 2-hydroxyphenyl-4-hydroxyphenylmethane 49.3 wt%, bis(4-hydroxyphenyl)methane 31.9 wt%, polynuclear content 9.9 wt%), 62 g of 94% paraformaldehyde, and 121 g of toluene. The atmosphere inside the reaction vessel was replaced with nitrogen, and the temperature of the mixed solution was brought to 70 °C. Subsequently, 60 g of 2-aminoethanol was added dropwise to the four-neck flask using the dropping funnel over 2 hours while maintaining the temperature at 70 °C. After the addition was completed, the mixture was stirred at 70 °C for an additional 3 hours. The composition of the reaction solution was analyzed by GPC using the analytical method described above. As a result, the proportion of the target compound present in the reaction solution was 51 area %. After the reaction was completed, toluene and water were removed by distillation under reduced pressure at 70°C. The pressure during distillation was gradually reduced to a final pressure of 4.8 kPa. The composition containing the target compound was extracted, cooled and solidified, pulverized, and dried at 60°C and 1.5 kPa to obtain 173 g of the target compound (purity 53%, 47% by area of ​​compounds with a higher molecular weight than the target compound). 1 The results of H-NMR analysis confirmed that the target compound with the above structure was obtained. 1 H-NMR analysis (400 MHz, solvent: CDCl3, reference material: tetramethylsilane) 2.43-2.72(2H,brm),2.71-3.16(4H,m),3.41-4.09(12H,m),4.69-5.01(4H,m),6.49-7.07(6H,m).

[0028] <Comparative Synthesis Example 1> (Synthesis of Comparative Example Compound A represented by the following chemical formula) [ka] A 1 L four-neck flask equipped with a thermometer, stirrer, condenser, and dropping funnel was charged with 100 g (0.44 mol) of bisphenol A, 56 g of 94% paraformaldehyde, and 184 g of toluene. The atmosphere inside the reaction vessel was replaced with nitrogen, and the temperature of the mixed solution was brought to 70°C. Subsequently, 53 g of 2-aminoethanol was added dropwise to the four-neck flask using the dropping funnel over 2 hours while maintaining the temperature at 70°C. After the addition was completed, the mixture was stirred at 70°C for an additional 9.5 hours. The composition of the reaction solution was analyzed by GPC using the above analytical method. As a result, the proportion of the target compound present in the reaction solution was 52 area %. After the reaction was completed, toluene and water were removed by distillation under reduced pressure at 70° C. The pressure during distillation was gradually reduced to a final pressure of 20 kPa. The composition containing comparative compound A was extracted to obtain 187 g of a composition containing comparative compound A (purity: 54%, 46% by area of ​​compounds with higher molecular weight than comparative compound A). 1 From the results of H-NMR analysis, it was confirmed that the benzoxazine compound of Comparative Example Compound A having the above chemical structure was obtained. 1 H-NMR analysis (400 MHz, solvent: CDCl3, reference material: tetramethylsilane) 1.14-1.96(6H,m),2.45-2.77(2H,brm),2.78-3.18(4H,m),3.28-4.19(10H,m),4.70-5.14(4H,m),6.56-7.13(6H,m).

[0029] <Comparative Synthesis Example 2> A Fa-type benzoxazine compound (comparative compound B) represented by the following structure, which is widely used as a benzoxazine compound, was synthesized as follows. [ka] A 1 L four-neck flask equipped with a thermometer, stirrer, condenser, and dropping funnel was charged with 83 g (0.41 mol) of bisphenol F, 77 g of aniline, 56 g of 94% paraformaldehyde, and 153 g of toluene. The atmosphere in the reaction vessel was replaced with nitrogen, and the temperature of the mixed solution was then raised to 90°C. The mixture was then stirred for 2 hours while maintaining the temperature at 90°C. The composition of the reaction solution was analyzed by GPC using the above analytical method, and the proportion of the target comparative compound B present in the reaction solution was found to be 71 area %. After the reaction was completed, toluene and water were removed by distillation under reduced pressure at 90° C. The pressure during distillation was gradually reduced to 20 kPa. The composition containing comparative compound B was extracted to obtain 178 g of a composition containing comparative compound B (purity: 69%, 31 area % of compounds with higher molecular weight than comparative compound B).

[0030] (Method for preparing test pieces of cured product of Example 1 compound) Comparative Example Compound A was filled into a silicone casting plate for DMA measurement. It was then heated at 175°C for 2 hours in a dryer (DP32, manufactured by Yamato Scientific Co., Ltd.) and then cooled. The surface of the obtained plate-shaped cured resin was polished with sandpaper to prepare a test piece of the cured resin.

[0031] <Curing characteristics evaluation, heat resistance evaluation> For each of the benzoxazine compounds obtained in Example 1, Comparative Synthesis Example 1, and Comparative Synthesis Example 2, evaluation of curing characteristics and heat resistance of the cured products (measurement of 5% weight loss temperature and glass transition temperature (Tg)) were carried out according to the above analytical methods. The results are summarized in the following Table 1. In the table, "-" indicates that the measurement was not performed, and the glass transition temperature (Tg) of Comparative Example Compound B indicates the value described in the Journal of Electronics Packaging, Vol. 14, No. 3, pp. 204-211, 2011. [Table 1]

[0032] As shown in Table 1, it was revealed that the compound of Example 1, which is a compound of the present invention, cures at a lower temperature than Comparative Example Compound A and the commonly used Fa-type benzoxazine compound (Comparative Example Compound B). This result indicates that the use of the novel benzoxazine compound represented by general formula (1) of the present invention can lower the temperature in the molding process of thermosetting resins, thereby enabling efficiency improvements through shorter heating and cooling times and energy savings, and is therefore extremely useful because it can also be used on materials (substrates) that are sensitive to heat. Furthermore, as shown in Table 1, when the 5% weight loss temperature of the cured product of Example 1 compound, which is a compound of the present invention, was compared, it was revealed that the cured product of Example Compound 1 was also superior in heat resistance to the cured product of Comparative Example Compound A. Compared to the cured product of Comparative Example Compound B, the cured product of Example Compound 1 was slightly inferior in 5% weight loss temperature, but it was revealed that it had sufficient heat resistance for applications in which benzoxazine compounds are used and was superior in glass transition temperature (Tg).

Claims

1. A benzoxazine compound represented by the following general formula (1): 【Chemistry 1】 (In the formula, R １ represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms, and R ２ represents an alkylene group having 1 to 6 carbon atoms.

2. A resin raw material composition comprising the benzoxazine compound according to claim 1.

3. A curable resin composition comprising the benzoxazine compound according to claim 1 or the resin raw material composition according to claim 2.

4. 4. The curable resin composition according to claim 3, comprising the benzoxazine compound according to claim 1 or the resin raw material composition according to claim 2, and one or more compounds selected from the group consisting of an epoxy resin, a benzoxazine compound other than the benzoxazine compound according to claim 1, a phenolic resin, and a bismaleimide compound.

5. A cured product obtained by curing the curable resin composition according to claim 3 or 4.

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