Benzoxazine compound-containing composition, curable resin composition, and cured product thereof

Abstract

The present invention addresses the problem of providing a benzoxazine compound-containing composition having a low melt viscosity, a curable resin composition, and a cured product thereof. As a solution, provided is a benzoxazine compound-containing composition characterized by containing a benzoxazine compound represented by general formula (1) and a compound group (A) having a molecular weight in the range of 1,000-10,000, the peak area of the compound group (A) in gel permeation chromatography measurement using a differential refractometer as a detector being in the range of 0.1-15 area% relative to the peak area of all components detected, and the melt viscosity at 100°C being in the range of 0.1-4.5 Pa∙S.

Description

[Technical Field]

[0001] The present invention relates to a benzoxazine compound-containing composition, a curable resin composition, and a cured product thereof. More specifically, the present invention relates to a low melt viscosity benzoxazine compound-containing composition, a curable resin composition containing the low melt viscosity benzoxazine compound-containing composition, and a cured product thereof. [Background technology]

[0002] Benzoxazine compounds are known as thermosetting resin raw materials that cure by ring-opening polymerization of the benzoxazine ring when heated without producing volatile by-products, and are used as raw materials for molded articles that can be used as materials for insulating substrates (Patent Document 1), liquid crystal alignment agents (Patent Document 2), resin compositions for semiconductor encapsulation (Patent Documents 3 and 4), etc. A resin composition containing the benzoxazine compound of the present invention represented by the following general formula (1) is known to improve the heat resistance (glass transition temperature: Tg) of the cured product (Patent Document 5), and therefore its use as an encapsulating resin for semiconductors is being considered. However, the benzoxazine compounds of the present invention represented by the following general formula (1) produced by the production methods described in Patent Documents 5 and 6, etc., have a high melt viscosity, and when they are handled at a high temperature in order to lower the melt viscosity, polymerization proceeds, which causes a problem that the range of application to transfer molding and compression molding, which are typical semiconductor encapsulation methods, is limited. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2007-002064 [Patent Document 2] Japanese Patent Application Laid-Open No. 2009-175684 [Patent Document 3] Japanese Patent Application Laid-Open No. 2015-025120 [Patent Document 4] Japanese Patent Application Laid-Open No. 2011-231196 [Patent Document 5] Japanese Patent Application Publication No. 2018-184533 [Patent Document 6] Japanese Patent Application Publication No. 2018-016684 Summary of the Invention [Problem to be solved by the invention]

[0004] An object of the present invention is to provide a composition containing a benzoxazine compound represented by the following general formula (1) which has a low melt viscosity, a curable resin composition using the same, and a cured product thereof. [Means for solving the problem]

[0005] As a result of intensive research to solve the above-mentioned problems, the present inventors have found that a benzoxazine compound-containing composition having a low melt viscosity can be obtained by adjusting the content of a compound group having a specific molecular weight within a specific range, and have completed the present invention.

[0006] The present invention is as follows. 1. A composition comprising a benzoxazine compound represented by the following general formula (1) and a compound group (A) having a molecular weight in the range of 1,000 to 10,000: In a measurement by gel permeation chromatography using a differential refractometer as a detector, the peak area of ​​the compound group (A) is in the range of 0.1 area % to 15 area % of the peak areas of all detected components; A benzoxazine compound-containing composition, characterized in that the melt viscosity at 100°C is in the range of 0.1 Pa·S to 4.5 Pa·S. [ka] (In the formula, each R is independently a hydrogen atom or a methyl group.) 2. The benzoxazine compound-containing composition according to 1., wherein in the measurement by gel permeation chromatography, the peak area of ​​the benzoxazine compound represented by general formula (1) is in the range of 62 area % to 90 area % of the peak areas of all detected components (provided that the sum of the peak area of ​​the benzoxazine compound represented by general formula (1), the peak area of ​​the compound group (A), and the peak areas of other detected components is 100 area %). 3. A curable resin composition comprising the benzoxazine compound-containing composition according to 1. or 2. 4. The curable resin composition according to 3., which contains the benzoxazine compound-containing composition according to 1. or 2., and one or more members selected from the group consisting of epoxy resins, benzoxazine compounds other than the benzoxazine compound represented by general formula (1), and novolac phenolic resins. 5. A cured product obtained by curing the curable resin composition according to 3. or 4. [Effects of the Invention]

[0007] The present invention provides a benzoxazine compound-containing composition having a low melt viscosity, which contains a benzoxazine compound represented by the above general formula (1) and has a melt viscosity at 100°C in the range of 0.1 Pa·S to 4.5 Pa·S. The benzoxazine compound-containing composition of the present invention contains a benzoxazine compound represented by the above general formula (1), which improves the heat resistance of the cured product, and has a low melt viscosity at temperatures at which polymerization does not proceed. This results in excellent workability, and when made into a curable resin composition, it becomes possible to increase the addition rate of fillers, etc., which greatly contributes to improving heat dissipation, and enables the encapsulation of semiconductors with more precise structures. Therefore, the composition is very useful because it can be used in a wide range of applications. The low melt viscosity benzoxazine compound-containing composition of the present invention, as well as the curable resin composition containing the composition and the cured product thereof, 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. [Brief explanation of the drawings]

[0008] [Figure 1] FIG. 1 shows a chart of gel permeation chromatography analysis in Example 1. [Figure 2] FIG. 1 shows a chart of gel permeation chromatography analysis in Example 2. [Figure 3] FIG. 1 shows a chart of gel permeation chromatography analysis in Example 3. [Figure 4] FIG. 1 shows a chart of gel permeation chromatography analysis in Example 4. [Figure 5] FIG. 1 shows a chart of gel permeation chromatography analysis in Example 5. [Figure 6] FIG. 1 shows a chart of gel permeation chromatography analysis in Example 6. [Figure 7] FIG. 1 shows a chart of gel permeation chromatography analysis of Example 7. [Figure 8] FIG. 1 is a chart showing the gel permeation chromatography analysis of Comparative Example 1. [Figure 9] FIG. 1 is a chart showing the gel permeation chromatography analysis of Comparative Example 2. [Figure 10] FIG. 10 is a chart showing the gel permeation chromatography analysis of Comparative Example 3. [Figure 11] FIG. 10 is a chart showing the gel permeation chromatography analysis of Comparative Example 4. [Figure 12] FIG. 1 shows a chart of gel permeation chromatography analysis of Example 8. [Figure 13] FIG. 10 is a chart showing the gel permeation chromatography analysis of Example 9. [Figure 14] FIG. 1 shows a chromatogram and peak positions obtained by an RI detector in the "Component Analysis of a Composition Containing Compound (1a)" in the Example. [Figure 15] FIG. 15 is a diagram showing the FT-IR spectrum of peak 1 in FIG. 14 (peak of compound group (A) of the present invention having a molecular weight in the range of 1,000 to 10,000). [Figure 16] FIG. 15 is a diagram showing the FT-IR spectrum of peak 7 in FIG. 14 (the peak representing compound (1a)). [Figure 17] FIG. 17 is a diagram showing the FT-IR spectrum in the range of 2600 to 3200 cm −1 when the FT-IR spectra of FIGS. 15 and 16 are normalized by the peak at 2849 cm −1 . DETAILED DESCRIPTION OF THE INVENTION

[0009] The benzoxazine compound-containing composition of the present invention contains a benzoxazine compound represented by the following general formula (1). [ka] (In the formula, each R is independently a hydrogen atom or a methyl group.) Specific examples of the benzoxazine compound represented by the general formula (1) include compounds (1a), (1b), and (1c) shown by the following chemical structures. [ka] [ka] [ka]

[0010] The benzoxazine compound of the present invention represented by general formula (1) can be produced by a method of cyclization by dehydration condensation reaction of 3,4'-diaminodiphenyl ether, one or more phenolic compounds selected from phenol, p-cresol, o-cresol, and m-cresol, and a formaldehyde selected from an aqueous formaldehyde solution, 1,3,5-trioxane, paraformaldehyde, etc., as shown in the following reaction formula. [ka] (In the formula, each R is independently a hydrogen atom or a methyl group.)

[0011] The low melt viscosity benzoxazine compound-containing composition of the present invention represented by general formula (1) can be obtained by mixing 3,4'-diaminodiphenyl ether in the presence of formaldehyde, a phenolic compound, and a solvent, typically over 1 to 10 hours, preferably 4 to 10 hours, and more preferably 5 to 10 hours. 3,4'-Diaminodiphenyl ether is typically mixed as a solution of the phenolic compound and / or solvent. Adding 3,4'-diaminodiphenyl ether to the reaction system over time allows the content of the compound group (A) having a molecular weight in the range of 1,000 to 10,000 to fall within a specific range. The amount of the phenol compound used in the above reaction is in the range of 2.0 to 10.0 mol, preferably in the range of 2.0 to 8.0 mol, and more preferably in the range of 2.0 to 6.0 mol, per 1 mol of 3,4'-diaminodiphenyl ether. The amount of formaldehyde used in the above reaction is in the range of 4.0 to 20.0 mol, preferably in the range of 4.0 to 16.0 mol, and more preferably in the range of 4.0 to 12.0 mol, per 1 mol of 3,4'-diaminodiphenyl ether.

[0012] 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 3 to 10 times, and preferably 4 to 6 times, the weight of 3,4'-diaminodiphenyl ether. The reaction temperature is usually in the range of 70 to 100° C., preferably in the range of 75 to 90° C. The reaction may be carried out under normal pressure, or under increased pressure or reduced pressure. 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, usable acid catalysts include concentrated hydrochloric acid, hydrochloric acid gas, trifluoroacetic acid, methanesulfonic acid, p-toluenesulfonic acid, benzoic acid, and mixtures thereof, and usable base catalysts include, but are not limited to, sodium hydroxide, sodium carbonate, triethylamine, triethanolamine, and mixtures thereof. 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] The reaction mixture thus obtained can be used to obtain the benzoxazine compound-containing composition of the present invention by known methods. For example, the reaction mixture is stirred (neutralization step) after adding an aqueous solution of sodium hydroxide, potassium hydroxide, or a basic compound such as sodium carbonate or potassium carbonate to the reaction mixture, and the mixture is allowed to stand to separate and remove the aqueous layer from the organic solvent layer. Water is then added to the organic solvent layer, and the process of stirring, standing, and separating and removing the aqueous layer (water-washing step) is repeated multiple times to thoroughly wash the organic solvent layer. The washed organic solvent layer is then distilled (distillation step) to remove the solvent and phenolic compounds, thereby obtaining the benzoxazine compound-containing composition of the present invention. The neutralization step, water-washing step, and distillation step are preferably carried out at temperatures ranging from 0 to 50°C, 0 to 90°C, and 50 to 100°C, respectively.

[0014] The benzoxazine compound-containing composition of the present invention is characterized by having a melt viscosity at 100°C in the range of 0.1 Pa·S to 4.5 Pa·S. The melt viscosity in the present invention means a value measured by using 15 g of the benzoxazine compound-containing composition using a Brookfield viscometer under the following measurement conditions. [Measurement conditions] Melt temperature: 100℃ Measurement time: Within 15 minutes after the composition is completely dissolved Time required for complete dissolution: Approximately 1 hour at an oil bath temperature of 100°C (±5°C) Rotation speed: 6.0 rpm The benzoxazine compound-containing composition of the present invention preferably has a melt viscosity at 100°C in the range of 0.5 Pa·S to 4.0 Pa·S, more preferably in the range of 0.5 Pa·S to 3.5 Pa·S. When the benzoxazine compound of the present invention is heated at a temperature exceeding 100° C., the benzoxazine compound is rapidly reduced due to polymerization and the amount of high-molecular-weight components such as compound group (A) increases. However, the benzoxazine compound-containing composition of the present invention is very useful because it has a low melt viscosity at temperatures at which such polymerization does not occur.

[0015] The benzoxazine compound-containing composition of the present invention is characterized in that, in a measurement by gel permeation chromatography using a differential refractometer as a detector, the peak area of ​​a compound group (A) having a molecular weight in the range of 1,000 to 10,000 is contained in the range of 0.1 area % to 15 area % relative to the peak areas of all detected components. In the analysis by infrared spectroscopy (IR), the benzoxazine compound represented by the general formula (1) and the compound group (A) are separated by a C-H stretch of a benzene ring at 2850 cm -1 When comparing the peak intensities normalized by the peak around 3000 cm, compound group (A) -1 It is characterized by a weak peak intensity around this region. The peak area of ​​this compound group (A) is preferably in the range of 0.1 area % to 14 area %, more preferably in the range of 0.1 area % to 13 area %, and particularly preferably in the range of 0.1 area % to 12 area %, relative to the peak areas of all detected components. Furthermore, in the benzoxazine compound-containing composition of the present invention, the peak area of ​​the benzoxazine compound represented by general formula (1) may be in the range of 62 area% to 82 area% of the peak area of ​​all detected components in the measurement by gel permeation chromatography, but it is preferable that it is in the range of 62 area% to 90 area% of the peak area of ​​all detected components. However, the sum of the peak area of ​​the benzoxazine compound represented by general formula (1), the peak area of ​​compound group (A), and the peak area of ​​other detected components is 100 area%. The peak area of ​​the benzoxazine compound represented by general formula (1) is more preferably in the range of 64 area% to 90 area%, and even more preferably in the range of 65 area% to 90 area%, of the peak area of ​​all detected components.

[0016] The values ​​measured by gel permeation chromatography using a differential refractometer as a detector for the benzoxazine compound-containing composition of the present invention are measured under the following measurement conditions. [Measurement conditions] Flow rate: 1mL / min Eluent: tetrahydrofuran Temperature: 40℃ Wavelength: 254nm Sampling pitch: 100 msec Measurement sample: 10 mg of a composition containing benzoxazine compounds diluted 600 times with tetrahydrofuran Injection volume: 20μL [Column] (Use the following column or equivalent from upstream.) TSKgel Guard Column HXL-L (Tosoh Corporation) TSKgel G4000HXL (Tosoh Corporation) (filler: styrene divinylbenzene polymer, exclusion limit: 4 x 10 5 Theoretical plate number: 16,000 (catalog value) TSKgel G3000HXL (Tosoh Corporation) (filler: styrene divinylbenzene polymer, exclusion limit: 6 x 10 4 Theoretical plate number: 16,000 (catalog value) TSKgel G2000HXL (Tosoh Corporation) (filler: styrene divinylbenzene polymer, exclusion limit: 1 x 10 4 Theoretical plate count: 16,000 (catalog value) 2 [Molecular weight calculation method] The molecular weight is calculated as a standard polystyrene equivalent using a calibration curve of a third-order approximation curve using polystyrene standard samples.

[0017] In another embodiment of the method for producing the benzoxazine compound-containing composition of the present invention, the benzoxazine compound-containing composition can be produced by mixing a benzoxazine compound-containing composition represented by general formula (1) obtained by a conventionally known method or a benzoxazine compound-containing composition obtained by the above-mentioned method with a crystal of the benzoxazine compound represented by general formula (1) obtained by the method described below, so as to obtain the benzoxazine compound-containing composition of the present invention. This mixing method includes a method in which each component is mixed in a solid state and melted to form a homogeneous composition, a method in which each component is mixed in a molten state to form a homogeneous composition, etc. To prevent deterioration due to the influence of oxygen, it is preferable to carry out the mixing in an inert gas atmosphere such as nitrogen. As shown in the following reaction scheme, a method for obtaining crystals of the benzoxazine compound represented by general formula (1) involves reacting 3,4'-diaminodiphenyl ether with a 2-hydroxybenzaldehyde compound (3) to obtain a compound represented by general formula (2), which is then reduced with sodium borohydride or the like to form a compound represented by general formula (4), which is then reacted with formalin to obtain the benzoxazine compound represented by general formula (1). The benzoxazine compound represented by general formula (1) obtained by this method can be obtained as highly pure crystals. [ka] (In the formula, each R is independently a hydrogen atom or a methyl group.)

[0018] The benzoxazine compound-containing composition of the present invention can be used as a curable resin composition containing the benzoxazine compound as an essential component. One embodiment of the curable resin composition is a curable resin composition obtained by mixing the benzoxazine compound-containing composition of the present invention 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.

[0019] Another embodiment is a curable resin composition containing the benzoxazine compound-containing composition of the present invention as an essential component and other polymeric materials. The polymer material constituting the curable resin composition of the present invention is not particularly limited, but may contain raw materials for each of an epoxy resin, a phenolic resin, a bismaleimide resin, and a benzoxazine compound other than the benzoxazine compound represented by general formula (1). 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 resin and bisphenol resin, and examples of the bismaleimide resin include raw materials for bismaleimide resins having the following structure. [ka]

[0020] Examples of benzoxazine compounds other than the benzoxazine compound represented by general formula (1) include benzoxazine compounds having structures represented by the following general formulas (A) to (C). [ka] (In the formula, Ra represents a divalent group having 1 to 30 carbon atoms (excluding diphenylether-3,4'-diyl), 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.)

[0021] In the benzoxazine compound having a structure represented by general formula (A), Ra represents a divalent group having 1 to 30 carbon atoms, excluding diphenylether-3,4'-diyl. 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, 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, and JBZ-OP100N and JBZ-BP100N manufactured by JFE Chemical.

[0022] 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 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 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. 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.

[0023] 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 composition containing a benzoxazine compound represented by the above general formula (1) and one or more compounds selected from the group consisting of epoxy resins, benzoxazine compounds other than the benzoxazine compound represented by the general formula (1), and novolac phenolic resins.

[0024] In the curable resin composition of the present invention, the mixing amount of the benzoxazine compound-containing composition represented by the general formula (1) and other polymeric materials is in the range of 0.01 to 100 parts by weight per 1 part by weight of the benzoxazine compound-containing composition represented by the general formula (1). The curable resin composition of the present invention can be obtained by adding the benzoxazine compound-containing composition represented by the general formula (1) to the polymeric material, if necessary. The method of addition is not particularly limited, and any conventionally known method can be used. Examples include a method of adding the composition during synthesis or polymerization of the polymeric material, a method of adding a resin made of the polymeric material to a molten resin in, for example, a melt extrusion process, and a method of 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 resin composition of the present invention is in a molten state. However, it is preferable to perform the treatment at an upper limit of 140°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.

[0025] Next, the cured product of the present invention will be described. The cured product of the present invention can be obtained by curing the benzoxazine compound-containing composition represented by general formula (1) of the present invention or the curable resin composition of the present invention. 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.

[0026] 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 140 to 250°C, preferably 160 to 220°C, and more preferably 160 to 200°C. In order to improve the mechanical properties of the resulting cured product, a temperature range of 180 to 200°C is particularly preferred. When curing is carried out within this temperature range, the reaction time may be approximately 2 to 10 hours. 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. [Example]

[0027] The present invention will be explained in more detail below with reference to examples. In the following examples, the physical properties were measured by the following methods. <Analysis method> 1. Melt viscosity Apparatus: B-type viscometer (TVB-10, rotor: THM-12 / manufactured by Toki Sangyo Co., Ltd.) [Measurement conditions] Sample amount: 15 g of benzoxazine compound-containing composition Melt temperature: 100℃ Measurement time: Within 15 minutes after the composition is completely dissolved Time required for complete dissolution: Approximately 1 hour at an oil bath temperature of 100°C (±5°C) Rotation speed: 6.0 rpm 2. Gel Permeation Chromatography Device: HLC-8320 / Tosoh Corporation Detector: Differential refractometer (RI) [Measurement conditions] Flow rate: 1mL / min Eluent: tetrahydrofuran Temperature: 40℃ Wavelength: 254nm Sampling pitch: 100 msec Measurement sample: 10 mg of a composition containing benzoxazine compounds diluted 600 times with tetrahydrofuran Injection volume: 20μL [Column] (from upstream) Guard Column HXL-L + G4000HXL + G3000HXL + G2000HXL x 2 (7.8 mm ID x 30 cm, Tosoh Corporation) [Molecular weight calculation method] The molecular weight was calculated as a standard polystyrene equivalent using a calibration curve of a third-order approximation curve using the following polystyrene standard sample. The measurement conditions were the same as above except that the injection volume was changed to 10 μL. (Polystyrene standard sample) TSKgel Standard Polystyrene A-500: Nominal Mol.Wt. 5.9 x 102 Mw / Mn 1.19 (0005203 / Tosoh Corporation) TSKgel Standard Polystyrene A-2500: Nominal Mol.Wt. 2.63 x 103 Mw / Mn 1.05 (0005205 / Tosoh Corporation) TSKgel Standard Polystyrene A-5000: Nominal Mol.Wt. 5.06 x 103 Mw / Mn 1.02 (0005206 / Tosoh Corporation) TSKgel Standard Polystyrene F-1: Nominal Mol.Wt. 1.02 x 104 Mw / Mn 1.02 (0005207 / Tosoh Corporation) TSKgel Standard Polystyrene F-2: Nominal Mol.Wt. 1.74 x 104 Mw / Mn 1.01 (0005208 / Tosoh Corporation) TSKgel Standard Polystyrene F-4: Nominal Mol.Wt. 3.79 x 104 Mw / Mn 1.01 (0005209 / Tosoh Corporation)

[0028] Example 1 A four-neck flask equipped with a thermometer, stirrer, and condenser was charged with 547 g (16.8 mol) of 92 wt% paraformaldehyde, 3336 g of toluene, and 394 g (4.19 mol) of phenol. After purging the reaction vessel with nitrogen, a solution of 839 g (4.19 mol) of 3,4'-diaminodiphenyl ether, 839 g of toluene, and 394 g (4.19 mol) of phenol dissolved at 70 °C was added dropwise over 6 hours at 80 °C (at a molar ratio of 3,4'-diaminodiphenyl ether, phenol, and paraformaldehyde of 1:2:4). The mixture was then stirred at 82 °C for 18 hours. Analysis of the reaction mixture by gel permeation chromatography under the above conditions revealed that the proportion of compound (1a) present in the reaction mixture was 70.2 area %. After the reaction was completed, 1800 g of 3% aqueous sodium hydroxide solution was added at 30°C with stirring, and the mixture was stirred for 30 minutes, then allowed to stand, and the aqueous layer was separated and removed. 2200 g of water was then added to the oil layer with stirring at 30°C, and the mixture was stirred for 30 minutes, then allowed to stand, and the aqueous layer was separated and removed. The process from adding water to removing the aqueous layer was repeated four times. Toluene and phenol were removed from the resulting oil layer by vacuum distillation. The temperature and pressure during distillation were gradually increased and reduced, ultimately reaching 90°C and 1.5 kPa. The molten liquid of the composition containing compound (1a) was extracted, cooled, solidified, and then pulverized to obtain 1,383 g of the composition containing compound (1a). The resulting composition is 1 H-NMR and13 From the results of C-NMR analysis, it was confirmed that the compound (1a) was contained.

[0029] The obtained compound (1a)-containing composition was analyzed by gel permeation chromatography using a differential refractometer as a detector under the above conditions, and the peak area of ​​compound (1a) relative to the peak areas of all detected components (hereinafter referred to as the peak area ratio of compound (1a)) was 70.3 area%. Furthermore, the peak area of ​​compound group (A) having a molecular weight of 1,000 to 10,000 relative to the peak areas of all detected components (hereinafter referred to as the peak area ratio of compound group (A)) was 9.5 area%. The chart of this gel permeation chromatography analysis is shown in Figure 1. Furthermore, the melt viscosity of 15 g of the obtained composition containing compound (1a) at 100°C measured using a B-type viscometer (TVB-10 / manufactured by Toki Sangyo Co., Ltd.) under the above measurement conditions was 1.8 Pa·S.

[0030] <Example 2> After the same steps of charging, reaction, and separation as in Example 1, the final temperature of the distillation step was set to 95° C. The molten liquid of the composition containing the compound (1a) was extracted, cooled to solidify, and then pulverized to obtain 1280 g of the composition containing the compound (1a). The resulting composition containing compound (1a) was analyzed by gel permeation chromatography using a differential refractometer as a detector. The peak area ratio of compound (1a) was 69.0% by area, and the peak area ratio of compound group (A) was 11.3% by area. The chart of this gel permeation chromatography analysis is shown in Figure 2. The melt viscosity at 100°C was 2.7 Pa·S.

[0031] Example 3 The same procedure as in Example 1 was carried out except that the dissolving solution was added dropwise intermittently over 4.5 hours, to obtain a composition containing the compound (1a). The obtained composition containing compound (1a) was analyzed by gel permeation chromatography using a differential refractometer as a detector. As a result, the peak area ratio of compound (1a) was 69.4% by area, and the peak area ratio of compound group (A) was 9.4% by area. The chart of this gel permeation chromatography analysis is shown in Figure 3. The melt viscosity at 100°C was 2.0 Pa·S.

[0032] Example 4 The same procedure as in Example 1 was carried out except that 3,4'-diaminodiphenyl ether, phenol, and paraformaldehyde were charged in a molar ratio of 1:4:8, to obtain a composition containing the compound (1a). The obtained composition containing compound (1a) was analyzed by gel permeation chromatography using a differential refractometer as a detector, and the peak area ratio of compound (1a) was 72.8% by area, and the peak area ratio of compound group (A) was 8.0% by area. The chart of this gel permeation chromatography analysis is shown in Figure 4. The melt viscosity at 100°C was 1.5 Pa·S.

[0033] <Example 5> The same procedure as in Example 1 was carried out except that the dissolving solution was added dropwise intermittently over 1 hour, to obtain a composition containing the compound (1a). The resulting composition containing compound (1a) was analyzed by gel permeation chromatography using a differential refractometer as a detector. The peak area ratio of compound (1a) was 65.4% by area, and the peak area ratio of compound group (A) was 14.9% by area. The chart of this gel permeation chromatography analysis is shown in Figure 5. The melt viscosity at 100°C was 2.2 Pa·S.

[0034] Example 6 The same procedure as in Example 1 was carried out except that the dissolving solution was added dropwise intermittently over a period of 2 hours, to obtain a composition containing the compound (1a). The obtained composition containing compound (1a) was analyzed by gel permeation chromatography using a differential refractometer as a detector. As a result, the peak area ratio of compound (1a) was 68.3% by area, and the peak area ratio of compound group (A) was 11.6% by area. The chart of this gel permeation chromatography analysis is shown in Figure 6. The melt viscosity at 100°C was 2.0 Pa·S.

[0035] Example 7 The same procedure as in Example 1 was carried out except that in the reaction step after the intermittent dropwise addition, the water produced by the reaction was removed by reducing the pressure, thereby obtaining a composition containing the compound (1a). The resulting composition containing compound (1a) was analyzed by gel permeation chromatography using a differential refractometer as a detector. The peak area ratio of compound (1a) was 62.7% by area, and the peak area ratio of compound group (A) was 11.8% by area. The chart of this gel permeation chromatography analysis is shown in Figure 7. The melt viscosity at 100°C was 2.1 Pa·S.

[0036] <Comparative Example 1: Manufacturing method described in Patent Document 5> A four-neck flask equipped with a thermometer, stirrer, and condenser was charged with 176.3 g of phenol, 150.0 g of 3,4'-diaminodiphenyl ether, and 750.0 g of toluene, and 257.1 g of 35% aqueous formalin solution was added dropwise over 35 minutes at an internal temperature of 65°C while stirring. After the addition was complete, simple distillation was carried out at 85°C under atmospheric pressure to distill off water and toluene, and the distilled toluene was returned to the flask. After an additional 35.3 g of phenol was added, the mixture was allowed to react under reflux at 86°C for 2 hours. After the reaction was completed, the internal temperature was lowered to room temperature, 300 g of 10% aqueous sodium hydroxide was added to the reaction mixture, and the mixture was stirred for 20 minutes, and the aqueous layer was separated and removed. 200 g of toluene was added to the resulting oil layer, and 800 g of 3.75% aqueous sodium hydroxide was added, and the mixture was stirred for 20 minutes, and the mixture was allowed to stand, and the aqueous layer was separated and removed. Next, 300 g of water was added to the obtained oil layer, and the mixture was stirred, followed by removing the water layer. This washing procedure was repeated six times. Toluene was removed from the washed oil layer under reduced pressure, yielding 185.1 g of a composition containing the compound (1a). The obtained composition containing compound (1a) was analyzed by gel permeation chromatography using a differential refractometer as a detector, and the peak area ratio of compound (1a) was 61.6% by area, and the peak area ratio of compound group (A) was 16.4% by area. The chart of this gel permeation chromatography analysis is shown in Figure 8. The melt viscosity at 100°C was 4.7 Pa·S.

[0037] <Comparative Example 2: Manufacturing method described in Patent Document 6> A four-neck flask equipped with a thermometer, a stirrer, and a condenser was charged with 52.5 g of 3,4'-diaminodiphenyl ether, 49.5 g of phenol, 34.5 g of 92% paraformaldehyde, and 250 g of toluene, and the mixture was reacted while dehydrating at 90° C. Thereafter, the mixture was heated to 110° C. to distill off the toluene, and then the remaining toluene and unreacted materials were removed by vacuum distillation at 125° C., yielding 118.2 g of a composition containing the compound (1a) described above. The obtained composition containing compound (1a) was analyzed by gel permeation chromatography using a differential refractometer as a detector, and the peak area ratio of compound (1a) was 50.0% by area, and the peak area ratio of compound group (A) was 20.3% by area. The chart of this gel permeation chromatography analysis is shown in Figure 9. The melt viscosity at 100°C was 5.6 Pa·S.

[0038] <Comparative Example 3> The same procedure as in Example 1 was carried out except that the dissolving solution was added all at once, to obtain the above-mentioned composition containing compound (1a). The obtained composition containing compound (1a) was analyzed by gel permeation chromatography using a differential refractometer as a detector. As a result, the peak area ratio of compound (1a) was 49.5% by area, and the peak area ratio of compound group (A) was 29.8% by area. The chart of this gel permeation chromatography analysis is shown in Figure 10. The melt viscosity at 100°C was 19.1 Pa·S.

[0039] <Comparative Example 4> The composition containing the compound (1a) was obtained according to the following reaction scheme and procedure. [ka] 127 g (0.64 mol) of 3,4'-diaminodiphenyl ether and 635 g of ethanol were placed in a four-neck flask equipped with a thermometer, stirrer, and condenser. After the atmosphere inside the reaction vessel was replaced with nitrogen, 168 g (1.38 mol) of 2-hydroxybenzaldehyde, a compound represented by formula (3a) above, was added dropwise at 40°C over 30 minutes. 630 g of ethanol was then added, and the mixture was stirred at 60°C for 2 hours and then refluxed at 78°C for 8 hours. After the reaction was complete, the reaction solution containing the compound represented by formula (2a) above was cooled to 25°C, 1138 g of ethanol was added, and 53 g (1.39 mol) of sodium borohydride was added intermittently over 2 hours. The mixture was then stirred at 25°C for 7 hours. After the reaction was completed, 1510 g of water was added and the mixture was stirred at 25°C for 14 hours. The resulting slurry was subjected to solid-liquid separation by filtration to obtain a solid. The resulting solid was washed twice with 300 g of 30% aqueous methanol solution and then with 500 g of water, and then dried under reduced pressure at 50°C to obtain 280 g of a solid compound represented by formula (4a). The purity determined by gel permeation chromatography analysis using a differential refractometer as a detector was 96.9 area %. A four-neck flask was charged with 280 g of the compound represented by general formula (4a), 2290 g of butyl acetate, 47 g (0.7 mol) of acetic acid, and 490 g of water. The atmosphere inside the reaction vessel was replaced with nitrogen, and the mixture was stirred at 70°C for 2 hours. The mixture was then allowed to stand and the aqueous layer was separated and removed. Next, 500 g of water was added to the oil layer with stirring at 70°C, and the mixture was stirred for 30 minutes. The mixture was then allowed to stand and the aqueous layer was separated and removed. The process of adding water and removing the aqueous layer was repeated four times. The pH of the oil layer at this time was 3. The resulting oil layer was cooled to 40°C, and while maintaining the temperature at 40°C, 207 g (2.4 mol) of 35% formalin was added dropwise over 30 minutes, followed by stirring at 40°C for 5 hours. Subsequently, a portion of the butyl acetate was distilled off under reduced pressure at 90°C to achieve a solids concentration of 50%. The resulting oil layer was gradually cooled to 25°C, and the precipitated crystals were filtered. The resulting crystals were heated to 60°C under reduced pressure and dried to obtain 190 g of a composition containing the compound (1a). The yield relative to 3,4'-diaminodiphenyl ether was 68%.

[0040] The resulting composition is 1 H-NMR and 13 From the results of C-NMR analysis, it was confirmed that the compound (1a) was contained. 1 H-NMR (400MHz) measurement (solvent: CDCl3): 4.64(s,2H:a),4.66(s,2H:a),5.37(s,2H:b),5.39(s,2H:b),6.53-6.55(ddd,1H:c),6.81-7.35(m,15H:others). 13 C-NMR (400MHz) measurement (solvent: CDCl3): 50.28(A), 50.36(A), 79.21(B), 80.14(B), 108.15(H), 110.60(I), 112.23(J), 114.69(C), 117.06(K), 120. 20(L),120.96(M),126.85(N),126.85(N),127,97(O),128.33(P),12 9.14(Q),130.20(R),149.90(D),151.27(E),154.38(F),159.06(G). The resulting composition containing compound (1a) was analyzed by gel permeation chromatography using a differential refractometer as a detector. The peak area of ​​compound (1a) was 92.9% by area, and the peak area of ​​compound (A) was 5.3% by area. The chart of this gel permeation chromatography analysis is shown in Figure 11. Furthermore, the obtained composition containing compound (1a) was heated to 100° C. to measure the melt viscosity at 100° C., but it did not melt.

[0041] Example 8 The compound (1a)-containing composition obtained in the same manner as in Example 3 and the compound (1a)-containing composition obtained in Comparative Example 4 were melt-mixed to obtain a compound (1a)-containing composition. The obtained composition containing compound (1a) was analyzed by gel permeation chromatography using a differential refractometer as a detector. As a result, the peak area ratio of compound (1a) was 79.7% by area, and the peak area ratio of compound group (A) was 7.8% by area. The chart of this gel permeation chromatography analysis is shown in Figure 12. The melt viscosity at 100°C was 1.4 Pa·S.

[0042] Example 9 The compound (1a)-containing composition obtained by the same method as in Example 3 and the compound (1a)-containing composition obtained in Comparative Example 4 were melt-mixed in a weight ratio different from that in Example 8 to obtain a compound (1a)-containing composition. The resulting composition containing compound (1a) was analyzed by gel permeation chromatography using a differential refractometer as a detector. The peak area ratio of compound (1a) was 87.7% by area, and the peak area ratio of compound group (A) was 4.9% by area. The chart of this gel permeation chromatography analysis is shown in Figure 13. The melt viscosity at 100°C was 1.1 Pa·S.

[0043] It was revealed that the benzoxazine compound-containing compositions of Comparative Examples 1 to 3, which are not specific examples of the present invention, have high melt viscosities, and are therefore limited in their applicability to, for example, transfer molding and compression molding, which are typical semiconductor encapsulation methods. Furthermore, it was revealed that the benzoxazine compound-containing composition of Comparative Example 4, which is not a specific example of the present invention, does not melt at 100°C, further limiting the range of application to various molding methods. In contrast, it was revealed that the benzoxazine compound-containing compositions of Examples 1 to 9, which are specific examples of the present invention, have a peak area ratio of compound group (A) within a specific range, and therefore the melt viscosity of the composition at 100° C. is significantly reduced. This demonstrates that the benzoxazine compound represented by general formula (1), which improves heat resistance, has excellent workability, allows for an increased addition rate of fillers, etc., and contributes greatly to improved heat dissipation, and enables the encapsulation of semiconductors with more precise structures, making it possible to use the compound in a wide range of applications and extremely useful.

[0044] <Component analysis of the composition containing compound (1a)> The compound (1a)-containing composition obtained in Example 3 was subjected to GPC-FTIR analysis to analyze each component. (1) GPC-FTIR measurement conditions GPC equipment: Prominence HPLC system (DGU-20A3 / LC-20AD / SIL-20AHT / CTO-20A / SPD-20A / RID-10A / CBM-20A) (Shimadzu Corporation) Detector: Differential refractometer (RI detector) FT-IR interface: LC Tranceform 600 (Lab Connection) ·FT-IR: Nicolet iS10 (manufactured by Thermo Scientific) Column (from upstream): Guard Column HXL-L + G4000HXL + G3000HXL + G2000HXL x 2 (7.8 mm ID x 30 cm, manufactured by Tosoh Corporation) Eluent: THF (HPLC grade, manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.) ·Flow rate: 1.0mL / min. Sample concentration: 2.0 mg / mL ·Injection volume: 500μL Column temperature: 40℃ Measurement wave number: 5000~650cm -1 ·Resolution: 4cm -1 Number of scans: 8 times / 1 point (2) Sample Pretreatment The sample was weighed, the eluent was added, and it was left to dissolve overnight. Then, it was gently shaken and filtered through a 0.45 μm PTFE cartridge filter. No undissolved matter was visually confirmed. (3) Molecular Weight Calculation Method The third-order approximation curve using the following standard polystyrene (PS) manufactured by Tosoh Corporation was used as a calibration curve. Therefore, the indicated molecular weight is the molecular weight in terms of standard PS. ·TSKgel Standard Polystyrene A-500: Nominal Mol.Wt. 5.9×10 2 Mw / Mn 1.19 (0005203 / Tosoh Corporation) ·TSKgel Standard Polystyrene A-2500: Nominal Mol.Wt. 2.63×10 3 Mw / Mn 1.05 (0005205 / Tosoh Corporation) ·TSKgel Standard Polystyrene A-5000: Nominal Mol.Wt. 5.06×10 3 Mw / Mn 1.02 (0005206 / Tosoh Corporation) ·TSKgel Standard Polystyrene F-1: Nominal Mol.Wt. 1.02×10 4 Mw / Mn 1.02 (0005207 / Tosoh Corporation) ·TSKgel Standard Polystyrene F-2: Nominal Mol.Wt. 1.74×10 4 Mw / Mn 1.01 (0005208 / Tosoh Corporation) ·TSKgel Standard Polystyrene F-4: Nominal Mol.Wt. 3.79×10 4 Mw / Mn 1.01 (0005209 / Tosoh Corporation)

[0045] <GPC-FTIR Analysis Results> The chromatogram and peak positions obtained by the RI detector are shown in Fig. 14. Peak 7 in FIG. 14 is the peak of compound (1a). Note that the injection volume was increased to increase IR sensitivity, so the separation of peaks 4 and 6 was insufficient. The average molecular weight of each peak is shown in Table 1 below. In Table 1, "Mn" means number average molecular weight, "Mw" means weight average molecular weight, "Mz" means average molecular weight, and "Mw / Mn" means polydispersity.

[0046] [Table 1]

[0047] As shown in Table 1, it was confirmed that peak 1 in FIG. 14 is the peak of compound group (A) of the present invention having a molecular weight in the range of 1,000 to 10,000. FT-IR spectra at the peak tops of peak 1 (a peak representing compound group (A) in the present invention having a molecular weight in the range of 1,000 to 10,000) and peak 7 (a peak representing compound (1a)) in FIG. 14 are shown in FIGS. 15 and 16. In the FT-IR spectra of Figures 15 and 16, the benzene ring CH stretching at 2849 cm -1 2600-3200 cm when normalized by the peak -1 The FT-IR spectrum of the compound group (A) (peak 1) of the present invention having a molecular weight in the range of 1,000 to 10,000 is shown in Figure 17. Compared with compound (1a) (peak 7), the FT-IR spectrum of the compound group (A) having a molecular weight in the range of 1,000 to 10,000 is -1 It was revealed that the peak intensity around this region was weak.

Claims

1. A benzoxazine compound-containing composition containing a benzoxazine compound represented by the following general formula (1) and a compound group (A) having a molecular weight in the range of 1,000 to 10,000: The benzoxazine compound-containing composition The compound is produced by mixing 3,4'-diaminodiphenyl ether for 1 to 10 hours in the presence of an aqueous formaldehyde solution, formaldehydes selected from 1,3,5-trioxane and paraformaldehyde, one or more phenolic compounds selected from phenol, p-cresol, o-cresol and m-cresol, and a solvent; In a measurement by gel permeation chromatography using a differential refractometer as a detector, the peak area of ​​the compound group (A) is in the range of 0.1 area % to 15 area % relative to the peak areas of all detected components; In the measurement by gel permeation chromatography, the peak area of ​​the benzoxazine compound represented by the general formula (1) is in the range of 62 area % to 90 area % of the peak areas of all detected components (provided that the sum of the peak area of ​​the benzoxazine compound represented by the general formula (1), the peak area of ​​the compound group (A), and the peak areas of other detected components is 100 area %); A benzoxazine compound-containing composition characterized by having a melt viscosity at 100°C in the range of 0.1 Pa·S to 4.5 Pa·S. 【Chemistry 1】 (In the formula, each R is independently a hydrogen atom or a methyl group.)

2. A curable resin composition comprising the benzoxazine compound-containing composition according to claim 1.

3. 3. The curable resin composition according to claim 2, comprising the benzoxazine compound-containing composition according to claim 1, and one or more selected from the group consisting of epoxy resins, benzoxazine compounds other than the benzoxazine compound represented by general formula (1), and novolac phenolic resins.

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

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