JP2016121209A - Benzoxazine compound, benzoxazine resin, method for producing benzoxazine compound, curable resin composition, its cured product, frp material, semiconductor sealing material, varnish, circuit board, prepreg, and build-up film - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a benzoxazine compound excellent in various physical properties such as heat resistance, resistance to heat decomposition, flame retardancy and dielectric characteristics in an obtained cured product; a benzoxazine resin; a method for producing the benzoxazine compound; a curable resin composition; its cured product; an FRP material; a semiconductor sealing material; a varnish; a circuit board; a prepreg; and a build-up film.SOLUTION: A benzoxazine compound is formed by reacting a phenol compound with a monoamine compound and formaldehyde. The phenol compound has a diarylene[b,d]furan structure, at least one arylene group in the two arylene groups forming the diarylene[b,d]furan structure has a naphthylene skeleton and each of the two arylene groups has a hydroxyl group in the aromatic ring thereof.SELECTED DRAWING: None

Description

  The present invention relates to a benzoxazine compound, a benzoxazine resin, a method for producing a benzoxazine compound, a curable resin composition, and its curing, which are excellent in various physical properties such as heat resistance, thermal decomposition resistance, flame retardancy and dielectric properties in the obtained cured product. Product, FRP material, semiconductor sealing material, varnish, circuit board, prepreg, and buildup film.

  Benzoxazine resins are used to produce prepregs, laminates, circuit boards, molding compounds, adhesives, sintered powders, castings, FRP matrix resins, and precision instrument parts. Such a resin is dimensionally stable, exhibits good electrical resistance and mechanical resistance, low shrinkage, low hygroscopicity, glass transition temperature in a cured product, and also exhibits good holding characteristics with respect to mechanical properties.

  As a typical benzoxazine compound, Patent Document 1 describes a compound obtained by reacting bisphenol F (or bisphenol A), aniline and formalin. However, when the benzoxazine compound is applied to a printed wiring board, the printed wiring board has a low dielectric constant because it can withstand higher communication speeds and transmission loss, and even when the operating environment temperature rises. Although it has been required to have high heat resistance and high heat decomposability while having properties such as rate and low dielectric loss tangent, the benzoxazine compound has not fully satisfied these properties. Furthermore, since the benzoxazine compound is inferior in flame retardancy compared to conventional benzoxazine resins and the like, it is necessary to blend various flame retardants in large amounts, but various flame retardants are blended in the benzoxazine compounds in large amounts. As a result, the workability is deteriorated and the glass transition temperature is lowered. For example, it cannot be used for circuit board materials that are becoming thinner and FRP composite materials having complicated shapes.

Japanese Patent Laid-Open No. 11-12258

  Therefore, the problem to be solved by the present invention is a method for producing a benzoxazine compound, a benzoxazine resin, a benzoxazine compound, which are excellent in various physical properties such as heat resistance, heat decomposability, flame retardancy and dielectric properties in the obtained cured product, The object is to provide a curable resin composition, a cured product thereof, an FRP material, a semiconductor sealing material, a varnish, a circuit board, a prepreg, and a buildup film.

  As a result of intensive studies to solve the above problems, the present inventors have found that a phenol compound having a diarylene [b, d] furan structure in which aromatic rings are bonded to each other without a methylene chain, a monoamine compound and formaldehyde, The benzoxazine compound obtained by reacting is found to be excellent in various physical properties such as heat resistance, heat decomposition resistance, flame retardancy, and dielectric properties in the obtained cured product, and the present invention has been completed.

  That is, the present invention has a diarylene [b, d] furan structure, and at least one of the two arylene groups forming the diarylene [b, d] furan structure has a naphthylene skeleton, and The present invention relates to a benzoxazine compound obtained by reacting a phenol compound in which each of the two arylene groups has a hydroxyl group on the aromatic ring, a monoamine compound and formaldehyde.

  The present invention further relates to a benzoxazine resin containing the benzoxazine compound.

  The present invention comprises a step of obtaining a phenol compound by reacting a compound (Q) having a quinone structure in the molecular structure with a compound (P) having a phenolic hydroxyl group in the molecular structure in the presence of an acid catalyst; And a step of reacting the phenol compound obtained in 1 above with a monoamine compound and formaldehyde, at least one of the compound (Q) having the quinone structure or the compound (P) having a phenolic hydroxyl group in the molecular structure. The compound relates to a method for producing a benzoxazine compound having a naphthalene ring in the molecule.

  The present invention further relates to a curable resin composition containing the benzoxazine compound or the benzoxazine resin as an essential component.

  The present invention further relates to a cured product obtained by curing the curable resin composition.

  The present invention further relates to an FRP material comprising the curable resin composition.

  The present invention further includes the curable resin composition and an inorganic filler, and the content of the inorganic filler is in the range of 30 to 95 parts by mass per 100 parts by mass of the curable resin composition. It relates to a stop material.

  The present invention further relates to a varnish obtained by adding an organic solvent to the curable resin composition.

  The present invention further relates to a circuit board obtained by laminating a varnish shaped like a plate with a copper foil, followed by heating and pressing.

  The present invention further relates to a prepreg obtained by impregnating a reinforcing substrate with the varnish and then semi-curing it.

  The present invention further relates to a build-up film obtained by applying the curable resin composition onto a substrate and then curing it.

  According to the present invention, a benzoxazine compound, a benzoxazine resin, a method for producing a benzoxazine compound, a curable resin composition excellent in various physical properties such as heat resistance, heat decomposition resistance, flame retardancy, and dielectric properties in the obtained cured product, The cured product, FRP material, semiconductor sealing material, varnish, circuit board, prepreg, and build-up film can be provided.

1 is a GPC chart of a phenol resin (A) obtained in Example 1. 2 is a GPC chart of a phenol resin (B) obtained in Example 2. 4 is a GPC chart of a phenol resin (C) obtained in Example 3.

Hereinafter, the present invention will be described in detail.
The benzoxazine compound of the present invention has a diarylene [b, d] furan structure, and at least one of the arylene groups forming the diarylene [b, d] furan structure has a naphthylene skeleton, In addition, each of the two arylene groups is a compound obtained by reacting a phenol compound having a hydroxyl group on the aromatic ring, a monoamine compound and formaldehyde.

  The benzoxazine compound of the present invention obtained as described above has a diarylene [b, d] furan structure in which aromatic rings are bonded to each other without a methylene chain, and is therefore rigid and has an aromatic ring in the compound. And a high concentration of the benzoxazine ring. That is, since the benzoxazine compound of the present invention has a molecular structure that does not have a methylene chain that is likely to be decomposed by heat as described above, the obtained cured product has a feature of high thermal decomposition resistance. Furthermore, since the benzoxazine compound of the present invention has a rigid molecular structure in which aromatic rings are bonded to each other as described above, molecular motion is suppressed, and the resulting cured product has a low dielectric constant and dielectric loss tangent, resulting in a dielectric property. It has the feature of being excellent. Furthermore, since the benzoxazine compound of the present invention has a high aromatic ring concentration in the compound in addition to the rigid molecular structure as described above, it has a feature that the obtained cured product is excellent in flame retardancy. In addition to the rigid molecular structure as described above, the benzoxazine compound of the present invention has a high concentration of benzoxazine rings, so that the resulting cured product has a high crosslink density and excellent heat resistance. That is, the benzoxazine compound obtained by reacting the phenol compound with a monoamine compound and formaldehyde has excellent characteristics such as heat resistance, heat decomposition resistance, flame retardancy, and dielectric properties in the obtained cured product. It is what you have.

  In general, in order to improve the heat resistance of a cured product, a method of polyfunctionalizing an aromatic ring with a nodule group such as formaldehyde is known, but a compound functionalized by such a method is known. Since the aromatic rings are knotted by only one knot group, the knot group is easily cleaved at the time of combustion, and the flame retardancy is low. In contrast, the benzoxazine compound of the present invention has a diarylene [b, d] furan structure in which aromatic rings are fixed by two bonds of an ether bond and a direct bond. These bonded bonds are not easily cleaved and exhibit high flame retardancy in the cured product. Furthermore, since at least one of the two arylene groups has a naphthalene skeleton, the aromatic ring concentration is further increased, and the resulting cured product exhibits extremely excellent flame retardancy.

  Since the benzoxazine compound of the present invention is further excellent in reactivity and excellent in heat resistance, heat decomposition resistance, and flame retardancy in a cured product, the phenol compound has the diarylene [b, d] furan structure. And at least one of the two arylene groups forming the diarylene [b, d] furan structure has a naphthylene skeleton, and each of the two arylene groups has a hydroxyl group on the aromatic ring. And it is preferable that at least one of the two arylene groups has a hydroxyl group at the para position of the carbon atom to which the oxygen atom forming the furan ring is bonded.

  Examples of the benzoxazine compound of the present invention obtained by reacting a phenol compound as described above with a monoamine compound and formaldehyde include those represented by the following structural formulas (III) to (VI).

In formulas (III) to (VI), each R ² is independently an alkyl group having 1 to 4 carbon atoms, an alkoxy group having 1 to 4 carbon atoms, an aryl group, or an aralkyl group, m is an integer of 0 to 4, and n is an integer of 0 to 3. When m or n is 2 or more, R ² may be the same or different from each other. Y and Z are bonded to adjacent carbon atoms on the aromatic ring and are each a pair represented by a hydroxyl group and a hydrogen atom, or a pair constituting a structural site represented by the following structural formula (VII). However, at least one pair of Y and Z in the molecule is a pair constituting a structural site represented by the following structural formula (VII). Further, in the formulas (III) to (V), R ² may be bonded to any of the two aromatic rings constituting the naphthalene ring, and Y bonded to the naphthalene ring to which R ² is bonded. And Z may be bonded to any of the two aromatic rings constituting the naphthalene ring.

In the formula (VII), * Y and * Z are the bonding points with the carbon atom to which Y is bonded, the carbon atom to which Z is bonded, and the compounds represented by the structural formulas (III) to (VI), respectively. R ³ is an aliphatic hydrocarbon group, an aromatic hydrocarbon group, or one or more hydrogen atoms of the aliphatic hydrocarbon group or the aromatic hydrocarbon group is a hydroxyl group, an alkoxy group or a halogen atom Any one of the structures substituted with any of the above.

Specific examples of R ³ include alkyl groups such as methyl, ethyl, propyl, butyl, pentyl, hexyl and cyclohexyl groups; alkenyl groups such as allyl groups; alkynyls such as propargyl groups Group; hydroxyl group-containing alkyl group such as hydroxyethyl group, hydroxypropyl group; alkoxy group-containing alkyl group such as methoxyethyl group, methoxypropyl group, allyloxymethyl group, allyloxypropyl group, propargyloxymethyl group, propargyloxypropyl group, etc. A halogenated alkyl group such as a chloromethyl group, a chloroethyl group, a chloropropyl group, a bromomethyl group, a bromoethyl group, a bromopropyl group, a fluoromethyl group, a fluoroethyl group or a fluoropropyl group; a phenyl group, a tolyl group, a xylyl group, a naphthyl group; Aryl groups such as groups; Hydroxyl-containing aryl groups such as droxyphenyl and hydroxynaphthyl groups; alkoxy-containing aryl groups such as methoxyphenyl, ethoxyphenyl, allyloxyphenyl, and propargyloxyphenyl; vinylphenyl, allylphenyl, ethynylphenyl And unsaturated hydrocarbon group-containing aryl groups such as propargylphenyl group; halogenated aryl groups such as chlorophenyl group, bromophenyl group, fluorophenyl group, chloronaphthyl group, bromonaphthyl group, and fluoronaphthyl group.

  Examples of the benzoxazine resin containing the benzoxazine compound of the present invention include, in addition to the benzoxazine compounds represented by the structural formulas (III) to (VI), the following structural formulas (III-1) to (VI- The compound represented by 2) may be contained.

In formulas (III-1) to (VI-2), s is an integer of 0 to 4, t is an integer of 0 to 2, and k is an integer of 1 to 2. x and y each represent a bonding point with the naphthalene ring and represent bonding to adjacent carbons so as to form a furan ring. R ² is each independently an alkyl group having 1 to 4 carbon atoms, an alkoxy group having 1 to 4 carbon atoms, an aryl group or an aralkyl group, and when s or t is an integer of 2 or more , R ² may be the same or different. Y and Z are bonded to adjacent carbon atoms on the aromatic ring, and are each a pair represented by a hydroxyl group and a hydrogen atom, or constitute a structural site represented by the structural formula (VII-2). Although it is one set, at least one set is a set constituting the structural portion represented by the structural formula (VII-2). Furthermore, in the formulas (III-1) to (V-2), R ² may be bonded to any aromatic ring among the two aromatic rings constituting the naphthalene ring. Y and Z bonded to the naphthalene ring to which R ² is bonded may be bonded to any of the two aromatic rings constituting the naphthalene ring.

In Formula (VII-1), ** Y and ** Z are the bonding points with the carbon atom to which Y is bonded in the compounds represented by Structural Formulas (III-1) to (VI-2), respectively. , Z is a bonding point to the carbon atom to which Z is bonded, and R ³ is an aliphatic hydrocarbon group, an aromatic hydrocarbon group, or one or more hydrogen atoms possessed by an aliphatic hydrocarbon group or an aromatic hydrocarbon group Is a structure substituted with any one of a hydroxyl group, an alkoxy group and a halogen atom. Specific groups represented by R ³ are as described above.

  In the structural formulas (III-1), (V-1), (VI-1), and (VI-2), k is an integer of 1 to 2. Here, the benzoxazine compound corresponding to the case where the value of k is 1 (hereinafter abbreviated as “binuclear compound (α1)”) is heat-resistant, heat-decomposable, flame-retardant and dielectric properties in the cured product. Excellent. Furthermore, the benzoxazine compound corresponding to the case where the value of k is 2 (hereinafter abbreviated as “trinuclear compound (α2)”) has higher molecular skeleton rigidity and higher aromatic ring concentration. The cured product is more excellent in heat resistance.

  Specifically, the benzoxazine compound or the benzoxazine resin as described above is a non-catalytic reaction between a compound (Q) having a quinone structure in the molecular structure and a compound (P) having a phenolic hydroxyl group in the molecular structure. Alternatively, a step of reacting in a temperature range of 40 to 180 ° C. under acid catalyst conditions to obtain a phenol compound or a phenol resin, and a step of reacting the phenol compound or phenol resin obtained in the above step with a monoamine compound and formaldehyde. A production method comprising: at least one of the compound (Q) having a quinone structure or the compound (P) having a phenolic hydroxyl group in the molecular structure is a compound having a naphthalene ring in the molecule Manufactured by.

  Examples of the compound (Q) having a quinone structure include compounds represented by the following structural formula (Q1) or (Q2).

In formula (Q1) or (Q2), each R ¹ is independently a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, an alkoxy group having 1 to 4 carbon atoms, an aryl group, or an aralkyl group. It is.

  Specific examples of the compound represented by the structural formula (Q1) or (Q2) include parabenzoquinone, 2-methylbenzoquinone, 2,3,5-trimethyl-benzoquinone, naphthoquinone, and these benzoquinones and naphthoquinones. Examples thereof include compounds in which one or more alkyl groups having 1 to 4 carbon atoms, alkoxy groups having 1 to 4 carbon atoms, aryl groups, and aralkyl groups are substituted. These may be used alone or in combination of two or more. Among them, it is preferable to use naphthoquinone because a benzoxazine compound or the benzoxazine resin excellent in heat resistance, heat decomposition resistance, and flame retardancy in a cured product can be obtained.

  Examples of the compound (P) having a phenolic hydroxyl group include compounds represented by the following structural formula (P1) or (P2).

In formula (P1) or (P2), each R ² is independently an alkyl group having 1 to 4 carbon atoms, an alkoxy group having 1 to 4 carbon atoms, an aryl group, or an aralkyl group, m is an integer of 0 to 4, n is an integer of 0 to 3, and p and q are integers of 2 or more. When m or n is 2 or more, R ² may be the same or different from each other. In formula (P2), the hydroxyl group bonded to the naphthalene ring may be bonded to any aromatic ring among the aromatic rings constituting the naphthalene ring.

  Specific examples of the compound represented by the structural formula (P1) or (P2) include 1,2-dihydroxybenzene, 1,3-dihydroxybenzene, 1,4-dihydroxybenzene, 1,4-dihydroxynaphthalene, 1,5-dihydroxynaphthalene, 1,6-dihydroxynaphthalene, 2,6-dihydroxynaphthalene, 2,7-dihydroxynaphthalene, and these dihydroxybenzenes, dihydroxynaphthalene, alkyl groups having 1 to 4 carbon atoms, carbon atoms Examples include compounds in which one to four alkoxy groups, aryl groups, and aralkyl groups are substituted. These may be used alone or in combination of two or more. Among them, since a benzoxazine compound having excellent heat resistance, heat decomposition resistance, and flame retardancy in a cured product is obtained, 1,4-dihydroxynaphthalene, 1,5-dihydroxynaphthalene, 1,6-dihydroxynaphthalene, 2,6 Either -dihydroxynaphthalene or 2,7-dihydroxynaphthalene is preferable, and 2,7-dihydroxynaphthalene is particularly preferable.

  The reaction between the compound (Q) having a quinone structure and the compound (P) having a phenolic hydroxyl group proceeds under non-catalytic conditions because of its high reactivity, but is preferably performed using an acid catalyst as appropriate. . Examples of the acid catalyst used here include inorganic acids such as hydrochloric acid, sulfuric acid, and phosphoric acid, organic acids such as methanesulfonic acid, p-toluenesulfonic acid, and oxalic acid, boron trifluoride, anhydrous aluminum chloride, and zinc chloride. And Lewis acid. When these acid catalysts are used, they should be used in an amount of 5.0% by mass or less based on the total mass of the compound (Q) having the quinone structure and the compound (P) having a phenolic hydroxyl group in the molecular structure. Is preferred.

  The reaction is preferably performed under solvent-free conditions, but may be performed in an organic solvent as necessary. Examples of the organic solvent used here include methyl cellosolve, isopropyl alcohol, ethyl cellosolve, toluene, xylene, and methyl isobutyl ketone. When these organic solvents are used, since the reaction efficiency is improved, the organic solvent is used for 100 parts by mass in total of the compound (Q) having a quinone structure and the compound (P) having a phenolic hydroxyl group in the molecular structure. It is preferable to use it in the ratio which becomes the range of 50-200 mass parts.

  After completion of the reaction between the compound (Q) having a quinone structure in the molecular structure and the compound (P) having a phenolic hydroxyl group in the molecular structure, a phenol compound or a phenol resin can be obtained by drying under reduced pressure. I can do it.

  As a phenol compound contained in such a phenol compound or phenol resin, the compound etc. which have a structure represented by following Structural formula (1)-(4) etc. can be mentioned, for example.

In formulas (1) to (4), each R ² is independently an alkyl group having 1 to 4 carbon atoms, an alkoxy group having 1 to 4 carbon atoms, an aryl group, or an aralkyl group, m is an integer of 0 to 4, and n is an integer of 0 to 3. When m or n is 2 or more, R ² may be the same or different from each other. x and y each represent a bonding point with the naphthalene ring and represent that they are bonded to adjacent carbon atoms of the naphthalene ring so as to form a furan ring with the oxygen atom. In the formulas (1) to (3), R ² bonded to the naphthalene ring and the hydroxyl group bonded to the naphthalene ring linked to the R ² are each an aromatic ring among the aromatic rings constituting the naphthalene ring. May be bonded to.

  In the reaction, in addition to the compounds represented by the structural formulas (1) to (4), for example, compounds represented by the following structural formulas (1 ′) to (4 ′) can be obtained. The phenol resin contains, for example, compounds represented by the following structural formulas (1 ′) to (4 ′) other than the phenol compounds represented by the structural formulas (1) to (4). Also good.

  In the formulas (1 ′) to (4 ′), k and i are integers of 1 to 2, respectively. x and y each represent a bonding point with the naphthalene ring and represent bonding to adjacent carbons so as to form a furan ring.

  In the structural formula (1 ′), (3 ′), or (4 ′), k is an integer of 1 to 2. Here, the binuclear phenol compound (β1) corresponding to the case where the value of k is 1 reacts with the monoamine compound and formaldehyde to give the binuclear compound (α1). On the other hand, the trinuclear phenol compound (β2) corresponding to the case where the value of k is 2 gives the trinuclear compound (α2).

  In addition, when a phenol resin contains the binuclear phenol compound (β1) or trinuclear phenol compound (β2) represented by the structure as described above, the binuclear phenol compound (β1) or the trinuclear phenol is used. The content of the compound (β2) in the entire resin is maintained in the subsequent reaction, and in the finally obtained benzoxazine resin, the binuclear compound (α1) and the trinuclear compound occupying the entire benzoxazine resin. The content of (α2) is approximately the same. Therefore, when it is desired to obtain a benzoxazine resin excellent in heat resistance, heat decomposition resistance, flame retardancy and dielectric properties in a cured product, a binuclear phenol compound (β1) or a 33 nuclear phenol compound ( The content of β2) is important.

  Subsequently, it is made to react with the monoamine compound and formaldehyde made to react with the obtained phenol compound or phenol resin. Examples of the monoamine compound include those represented by the following structural formula (R).

In the formula (R), R ³ represents an aliphatic hydrocarbon group, an aromatic hydrocarbon group, or one or more hydrogen atoms of the aliphatic hydrocarbon group or the aromatic hydrocarbon group are a hydroxyl group, an alkoxy group, or a halogen atom. Any of the structures substituted with any of the above. Specific groups for R ³ are as described above.

Among these, R ³ is preferably an aryl group, and more preferably a phenyl group, because of excellent reactivity and excellent heat resistance and heat decomposability in a cured product.

  As the formaldehyde, formalin which is in a solution state or paraformaldehyde which is in a solid state can be used, and any of them may be used.

  The reaction between the phenol compound or the phenol resin and the monoamine compound efficiently produces the target benzoxazine resin. Therefore, one monoamine compound is added to 1 mol of the hydroxyl group in the phenol compound or the phenol resin. It is preferable to make it react in the range of 0.0-1.2 mol. In addition, since the target benzoxazine resin is generated more efficiently, the phenol compound or the phenol resin and the formaldehyde have 2 formsaldehyde per 1 mol of the hydroxyl group in the phenol compound or the phenol resin. It is more preferable to make it react in the range of 0.0-2.2 mol.

  The reaction of the phenol compound or the phenol resin with the monoamine compound and formaldehyde may be performed in the presence of a catalyst as necessary. Examples of the catalyst used here include various catalysts usually used in the production of dihydrooxazine compounds. Specifically, amide compounds such as N, N-dimethylformamide; pyridine, N, N-dimethyl-4- Pyridine compounds such as aminopyridine; amine compounds such as triethylamine and tetramethylethylenediamine; quaternary ammonium salts such as tetrabutylammonium bromide; organic acid compounds such as acetic acid, trifluoroacetic acid, paratoluenesulfonic acid and trifluoromethanesulfonic acid; water Alkali metal hydroxides or carbonates such as potassium oxide, potassium carbonate, sodium carbonate; phenolic compounds such as dibutylhydroxytoluene; palladium, tetrakis (triphenylphosphine) palladium, copper iodide, tin tetrachloride, nickel, platinum, etc. Gold Catalyst and the like. These may be used alone or in combination of two or more.

  The reaction of the phenol compound or the phenol resin with the monoamine compound and formaldehyde may be performed in an organic solvent as necessary. Examples of the organic solvent used herein include alcohol compounds such as water, methanol, ethanol, and isopropanol; ether compounds such as dioxane, tetrahydrofuran, and diethyl ether; acetic acid compounds such as acetic acid and trifluoroacetic acid; acetone, methyl ethyl ketone, methyl isobutyl ketone, Ketone compounds such as cyclohexanone; Acetic ester compounds such as ethyl acetate, butyl acetate, cellosolve acetate, propylene glycol monomethyl ether acetate and carbitol acetate; Carbitol compounds such as cellosolve and butyl carbitol; Dichloromethane, chloroform, carbon tetrachloride, dichloroethane Chlorinated hydrocarbon compounds such as chlorobenzene; Hydrocarbon compounds such as cyclohexane, benzene, toluene and xylene; Dimethylforma De, dimethyl acetamide, amide compounds such as N- methylpyrrolidone; amine compounds such as aniline; dimethyl sulfoxide, acetonitrile and the like. These may be used alone or as a mixed solvent of two or more.

  The reaction of the phenol compound or the phenol resin with the monoamine compound and formaldehyde can be performed under a temperature condition of 50 to 150 ° C., for example. After completion of the reaction, the water layer and the organic layer are separated, and then the organic solvent is dried under reduced pressure from the organic layer, whereby the target benzoxazine compound or benzoxazine resin can be obtained. In order to obtain a benzoxazine compound from a benzoxazine resin, it may be isolated by, for example, purification of a mixture by a known crystallization or solvent washing technique or a chromatography method.

  The benzoxazine compound of the present invention has a diarylene [b, d] furan structure, and at least one of the arylene groups forming the diarylene [b, d] furan structure has a naphthylene skeleton, In any case, the two arylene groups are compounds obtained by reacting a phenol compound having a hydroxyl group on the aromatic ring or a phenol resin containing such a phenol compound with a monoamine compound and formaldehyde. In addition, the obtained cured product has an effect of being excellent in various physical properties such as heat resistance, heat decomposition resistance, flame retardancy, and dielectric properties. Hereinafter, the phenol compound used to obtain the benzoxazine compound of the present invention and the phenol resin containing the phenol compound will be described in more detail.

<Phenol compound, phenol resin>
As the phenol compound, a phenol compound having a predetermined diarylene [b, d] furan structure as described above can be used. As such a phenol compound, specifically, phenol compounds represented by the following structural formulas (I) and (II) can be used.

In formulas (I) and (II), each R ¹ is independently a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, an alkoxy group having 1 to 4 carbon atoms, an aryl group, or an aralkyl group. It is. Ar ¹ is a structural moiety represented by the following structural formula (i), and Ar ² is a structural moiety represented by the following structural formula (i) or (ii).

In formulas (i) and (ii), R ² is each independently an alkyl group having 1 to 4 carbon atoms, an alkoxy group having 1 to 4 carbon atoms, an aryl group, or an aralkyl group, m Is an integer from 0 to 4, and n is an integer from 0 to 3. When m or n is 2 or more, R ² may be the same or different from each other. x and y each represent a bonding point with the naphthalene ring and represent that they are bonded to adjacent carbon atoms of the naphthalene ring so as to form a furan ring with the oxygen atom. In formula (i), R ² and a hydroxyl group bonded to the naphthalene ring may be bonded to any aromatic ring among the aromatic rings constituting the naphthalene ring.

  More specifically, a phenol compound represented by any one of the following structural formulas (1) to (4) described above can be given.

In formulas (1) to (4), each R ² is independently an alkyl group having 1 to 4 carbon atoms, an alkoxy group having 1 to 4 carbon atoms, an aryl group, or an aralkyl group, m is an integer of 0 to 4, and n is an integer of 0 to 3. When m or n is 2 or more, R ² may be the same or different from each other. x and y each represent a bonding point with the naphthalene ring and represent that they are bonded to adjacent carbon atoms of the naphthalene ring so as to form a furan ring with the oxygen atom. In the formulas (1) to (3), R ² bonded to the naphthalene ring and the hydroxyl group bonded to the naphthalene ring linked to the R ² are each an aromatic ring among the aromatic rings constituting the naphthalene ring. May be bonded to.

  More specifically, examples of the phenol compound represented by the structural formula (1) include phenol compounds represented by the following structural formulas (1-1) to (1-9).

  The phenol compound represented by the above (1) represented by the structural formulas (1-1) to (1-9) is, for example, parabenzoquinone as the compound (Q) having a quinone structure in the molecular structure, Various dihydroxynaphthalene can be used as the compound (P) having a phenolic hydroxyl group in the molecular structure, and can be produced by the method described above. At this time, since the reaction ratio of parabenzoquinone and dihydroxynaphthalene can produce the compound represented by the structural formula (1) with high efficiency, the amount of dihydroxynaphthalene is 0.1 to 10.0 mol per 1 mol of parabenzoquinone. It is preferable that the ratio is in the range.

  Among the phenol compounds represented by any one of the structural formulas (1-1) to (1-9), by reacting with a monoamine compound and formaldehyde, heat resistance, heat decomposition resistance, flame retardancy and The compound represented by the structural formula (1-8) or (1-9) is preferable because a benzoxazine compound that is superior in various physical properties of dielectric properties can be obtained. That is, a phenol compound obtained by using 2,7-dihydroxynaphthalene as the compound (P) having a phenolic hydroxyl group in the molecular structure is preferable.

  As a phenol resin, you may contain phenol compounds other than the phenol compound represented by the said Structural formula (1). Among these, since a benzoxazine resin having particularly high heat resistance can be obtained by reacting with a monoamine compound and formaldehyde, it preferably contains a polyfunctional compound represented by the following structural formula (1 ').

  In the formula (1 ′), k is an integer of 1 to 2. The hydroxyl group bonded to the naphthalene ring may be bonded to any aromatic ring among the aromatic rings constituting the naphthalene ring.

  In this case, the content ratio of each component in the phenol resin is such that the content ratio of the dinaphtho [b, d] furan compound represented by the structural formula (1) is in the range of 5 to 60% in terms of the area ratio in GPC measurement. And it is preferable that the content rate of the polyfunctional compound represented by the said structural formula (1 ') is the range of 10 to 70% by the area ratio in GPC measurement.

In addition, in this invention, the content rate of each component in a phenol resin is a ratio of the peak area of each said component with respect to the total peak area of a phenol resin computed from the GPC measurement data by the following conditions.
<GPC measurement conditions>
Measuring device: “HLC-8220 GPC” manufactured by Tosoh Corporation
Column: Guard column “HXL-L” manufactured by Tosoh Corporation
+ "TSK-GEL G2000HXL" manufactured by Tosoh Corporation
+ "TSK-GEL G2000HXL" manufactured by Tosoh Corporation
+ Tosoh Corporation “TSK-GEL G3000HXL”
+ Tosoh Corporation “TSK-GEL G4000HXL”
Detector: RI (differential refractometer)
Data processing: “GPC-8020 Model II version 4.10” manufactured by Tosoh Corporation
Measurement conditions: Column temperature 40 ° C
Developing solvent Tetrahydrofuran
Flow rate: 1.0 ml / min Standard: The following monodisperse polystyrene having a known molecular weight was used in accordance with the measurement manual of “GPC-8020 Model II version 4.10”.
(Polystyrene used)
“A-500” manufactured by Tosoh Corporation
"A-1000" manufactured by Tosoh Corporation
"A-2500" manufactured by Tosoh Corporation
"A-5000" manufactured by Tosoh Corporation
“F-1” manufactured by Tosoh Corporation
"F-2" manufactured by Tosoh Corporation
“F-4” manufactured by Tosoh Corporation
“F-10” manufactured by Tosoh Corporation
“F-20” manufactured by Tosoh Corporation
“F-40” manufactured by Tosoh Corporation
“F-80” manufactured by Tosoh Corporation
“F-128” manufactured by Tosoh Corporation
Sample: A 1.0 mass% tetrahydrofuran solution filtered in terms of resin solids and filtered through a microfilter (50 μl).

  More specifically, examples of the phenol compound represented by the structural formula (2) include a phenol compound represented by any one of the following structural formulas (2-1) to (2-9).

  The phenol compound represented by the structural formula (2) represented by the structural formulas (2-1) to (2-9) is, for example, 2 as the compound (Q) having a quinone structure in the molecular structure. 3,5-Trimethyl-parabenzoquinone can be produced by the above-described method using various dihydroxynaphthalenes as the compound (P) having a phenolic hydroxyl group in the molecular structure. At this time, since the reaction ratio of 2,3,5-trimethyl-parabenzoquinone and dihydroxynaphthalene can produce the compound represented by the structural formula (2) with high efficiency, 2,3,5-trimethyl-parabenzoquinone 1 It is preferable that the ratio of dihydroxynaphthalene is in the range of 0.1 to 10.0 moles per mole.

  Among phenol compounds represented by any one of the structural formulas (2-1) to (2-9), by reacting with a monoamine compound and formaldehyde, heat resistance, heat decomposition resistance, flame retardancy and The compound represented by the structural formula (2-8) or (2-9) is preferable because a benzoxazine compound that is more excellent in various physical properties of dielectric properties can be obtained. That is, a phenol compound obtained by using 2,7-dihydroxynaphthalene as the compound (P) having a phenolic hydroxyl group in the molecular structure is preferable.

  As a phenol resin, you may contain phenol compounds other than the phenol compound represented by the said Structural formula (2). Among these, since a benzoxazine resin having particularly high heat resistance can be obtained by reacting with a monoamine compound and formaldehyde, it preferably contains a polyfunctional compound represented by the following structural formula (2 ′).

  In formula (2 ′), the hydroxyl group bonded to the naphthalene ring may be bonded to any aromatic ring among the aromatic rings constituting the naphthalene ring.

  In this case, the content ratio of each component in the phenol resin is such that the content ratio of the dinaphtho [b, d] furan compound represented by the structural formula (2) is in the range of 50 to 95% as an area ratio in GPC measurement. And it is preferable that the content rate of the polyfunctional compound represented by the said structural formula (2 ') is the range of 1 to 50% by the area ratio in GPC measurement.

  More specifically, the phenol compound represented by the structural formula (3) includes a phenol compound represented by any one of the following structural formulas (3-1) to (3-9).

  The phenol compound represented by the structural formula (3) typified by the structural formulas (3-1) to (3-9) is, for example, 1 as the compound (Q) having a quinone structure in the molecular structure. 4-Naphthoquinone can be produced by the above-described method using various dihydroxynaphthalenes as the compound (P) having a phenolic hydroxyl group in the molecular structure. At this time, since the reaction rate of 1,4-naphthoquinone and dihydroxynaphthalene can produce the compound represented by the structural formula (1) with high efficiency, the amount of dihydroxynaphthalene is 0.1 with respect to 1 mol of 1,4-naphthoquinone. The ratio is preferably in the range of ˜10.0 mol.

  Among the phenol compounds represented by any of the structural formulas (3-1) to (3-9), by reacting with a monoamine compound and formaldehyde, heat resistance, heat decomposition resistance, flame retardancy and The compound represented by the structural formula (3-8) or (3-9) is preferable because a benzoxazine compound that is superior in various physical properties of dielectric properties can be obtained. That is, a phenol compound obtained by using 2,7-dihydroxynaphthalene as the compound (P) having a phenolic hydroxyl group in the molecular structure is preferable.

  As a phenol resin, you may contain phenol compounds other than the phenol compound represented by the said Structural formula (3). When the phenol resin contains other phenol compounds other than the compound represented by the structural formula (3), the content of the dinaphtho [b, d] furan compound represented by the structural formula (3) in the phenol resin Is preferably in the range of 5 to 70% in terms of area ratio in GPC measurement.

  Specific examples of other phenol compounds are represented by the following structural formula (3 ′) or (3 ″) because a benzoxazine resin having particularly high heat resistance can be obtained by reacting with a monoamine compound and formaldehyde. Polyfunctional compounds are preferred.

  In the formulas (3 ′) to (3 ″), k is an integer of 1 to 2. In the formula (3 ″), x and y represent points of attachment to the naphthalene ring, and are mutually connected to form a furan ring. Bond to adjacent carbon. In the formula (3 ′), the hydroxyl group on the naphthalene ring linked to 1,4-dihydroxynaphthalene may be bonded to any aromatic ring among the aromatic rings constituting the naphthalene ring. In the formula (3 ″), the hydroxyl group on dihydroxynaphthalene may be bonded to any aromatic ring among the aromatic rings constituting the dihydroxynaphthalene. Furthermore, the hydroxyl group on the naphthalene ring connected to the dihydroxynaphthalene may be bonded to any aromatic ring among the aromatic rings constituting the naphthalene ring.

  When the phenol resin contains the polyfunctional compound represented by the structural formula (3 ′), the content is preferably in the range of 2 to 60% in terms of area ratio in GPC measurement. Moreover, when a phenol resin contains the polyfunctional compound represented by the said structural formula (3 ''), it is preferable that the content rate is the range of 2-40% by the area ratio in GPC measurement.

  More specifically, the phenol compound represented by the structural formula (4) includes a phenol compound represented by any one of the following structural formulas (4-1) to (4-4).

  The phenol compound represented by the structural formula (4) represented by the structural formulas (4-1) to (4-4) is, for example, as a compound (Q) having a quinone structure in the molecular structure. 4-Naphthoquinone can be produced by the above-described method using various dihydroxybenzenes as the compound (P) having a phenolic hydroxyl group in the molecular structure. At this time, since the reaction rate of 1,4-naphthoquinone and dihydroxybenzene can produce the compound represented by the structural formula (1) with high efficiency, the amount of dihydroxybenzene is 0.1 per mol of 1,4-naphthoquinone. The ratio is preferably in the range of ˜10.0 mol.

  Among the phenolic compounds represented by any one of the structural formulas (4-1) to (4-4), by reacting with a monoamine compound and formaldehyde, heat resistance, heat decomposition resistance, flame retardancy and The compound represented by the structural formula (4-2) or (4-3) is preferable because a benzoxazine compound that is superior in various physical properties of dielectric properties can be obtained. That is, a phenol compound obtained by using 1,3-dihydroxybenzene as the compound (P) having a phenolic hydroxyl group in the molecular structure is preferable.

  As a phenol resin, you may contain phenol compounds other than the phenol compound represented by the said Structural formula (4). Among these, since a benzoxazine resin having particularly high heat resistance can be obtained by reacting with a monoamine compound and formaldehyde, it preferably contains a polyfunctional compound represented by the following structural formula (4 ′).

  In formula (4 '), k and i are each an integer of 1 to 2.

  In this case, the content ratio of each component in the phenol resin is such that the content ratio of the dinaphtho [b, d] furan compound represented by the structural formula (4) is in the range of 5 to 70% as an area ratio in GPC measurement. And it is preferable that the content rate of the polyfunctional compound represented by the said Structural formula (4 ') is the range of 1 to 60% by the area ratio in GPC measurement.

  Among these exemplified phenol compounds, the reaction with the monoamine compound and formaldehyde yields a benzoxazine compound that is excellent in balance between heat resistance, heat decomposition resistance, and flame retardancy in the cured product. ) To (3) are preferred, and phenol compounds represented by the structural formula (3) are particularly preferred.

  Next, the curable resin composition of the present invention will be described. The curable resin composition of the present invention comprises the benzoxazine compound or benzoxazine resin of the present invention described in detail above as an essential component. Since the benzoxazine compound or benzoxazine resin itself can be cured, the resin component of the curable resin composition of the present invention may be composed only of the benzoxazine compound or benzoxazine resin. Other resins may be used in combination.

  Examples of other resins include epoxy resins, phenolic hydroxyl group-containing resins, active ester resins, cyanate ester resins, vinyl benzyl compounds, acrylic compounds, maleimide compounds, and copolymers of styrene and maleic anhydride.

  Examples of the epoxy resin include bisphenol A type epoxy resin, bisphenol F type epoxy resin, bisphenol E type epoxy resin, bisphenol S type epoxy resin, bisphenol sulfide type epoxy resin, phenylene ether type epoxy resin, naphthylene ether type epoxy resin, Biphenyl type epoxy resin, tetramethyl biphenyl type epoxy resin, polyhydroxynaphthalene type epoxy resin, phenol novolac type epoxy resin, cresol novolac type epoxy resin, triphenylmethane type epoxy resin, tetraphenylethane type epoxy resin, dicyclopentadiene-phenol Addition reaction type epoxy resin, phenol aralkyl type epoxy resin, naphthol novolak type epoxy resin, naphthol aralkyl type epoxy resin Resin, naphthol-phenol co-condensed novolak type epoxy resin, naphthol-cresol co-condensed novolac type epoxy resin, aromatic hydrocarbon formaldehyde resin-modified phenol resin type epoxy resin, biphenyl-modified novolac type epoxy resin, anthracene type epoxy resin, etc. . These may be used alone or in combination of two or more.

  Among these epoxy resins, tetramethylbiphenol type epoxy resin, biphenyl aralkyl type epoxy resin, naphthylene ether type epoxy resin, polyhydroxynaphthalene type epoxy resin, novolak are particularly preferable in that a cured product having excellent flame retardancy can be obtained. It is preferable to use a type epoxy resin, and a dicyclopentadiene-phenol addition reaction type epoxy resin is preferable in that a cured product having excellent dielectric properties can be obtained.

  When an epoxy resin is used in combination with the benzoxazine resin of the present invention, the ratio between the total number of moles (a) of the oxazine structure and the phenolic hydroxyl group in the benzoxazine resin and the number of moles (b) of the epoxy groups in the epoxy resin. [(A) / (b)] is a ratio of 1.0 / 0.1 to 1.0 / 1.0, more preferably a ratio of 1.0 / 0.1 to 1.0 / 0.5 It is preferable that a cured product having excellent heat resistance and thermal decomposition resistance in the cured product is obtained.

  Examples of the phenolic hydroxyl group-containing compound include phenol novolak resins, cresol novolak resins, aromatic hydrocarbon formaldehyde resin-modified phenol resins, naphthylene ether resins, dicyclopentadiene phenol addition resins, phenol aralkyl resins, naphthol aralkyl resins, triphenyl resins. Methylol methane resin, tetraphenylol ethane resin, naphthol novolac resin, naphthol-phenol co-condensed novolac resin, naphthol-cresol co-condensed novolac resin, biphenyl-modified phenol resin (polyhydric phenol compound in which phenol nucleus is linked by bismethylene group), Biphenyl-modified naphthol resin (polyvalent naphthol compound in which phenol nuclei are linked by bismethylene groups), aminotriazine-modified phenol resin (melamine) Polyhydric phenol compound phenol nuclei are connected by benzoguanamine), and the like. These may be used alone or in combination of two or more.

  Among these phenolic hydroxyl group-containing compounds, those containing a large amount of an aromatic skeleton in the molecular structure are preferred because of their excellent dielectric properties and moisture absorption resistance. Specifically, phenol novolak resins, cresol novolak resins, aromatic carbonizations are preferred. Hydrogen formaldehyde resin-modified phenol resin, naphthylene ether resin, phenol aralkyl resin, naphthol aralkyl resin, naphthol novolak resin, naphthol-phenol co-condensed novolak resin, naphthol-cresol co-condensed novolak resin, biphenyl-modified phenol resin, biphenyl-modified naphthol resin, Aminotriazine modified phenolic resins are preferred.

  Examples of the cyanate ester resin include bisphenol A type cyanate ester resin, bisphenol F type cyanate ester resin, bisphenol E type cyanate ester resin, bisphenol S type cyanate ester resin, bisphenol sulfide type cyanate ester resin, phenylene ether type cyanate ester resin, Naphthylene ether type cyanate ester resin, biphenyl type cyanate ester resin, tetramethylbiphenyl type cyanate ester resin, polyhydroxynaphthalene type cyanate ester resin, phenol novolac type cyanate ester resin, cresol novolac type cyanate ester resin, triphenylmethane type cyanate ester Resin, tetraphenylethane type cyanate ester resin, DISIC Pentadiene-phenol addition reaction type cyanate ester resin, phenol aralkyl type cyanate ester resin, naphthol novolak type cyanate ester resin, naphthol aralkyl type cyanate ester resin, naphthol-phenol co-condensed novolak type cyanate ester resin, naphthol-cresol co-condensed novolak type cyanate Examples include ester resins, aromatic hydrocarbon formaldehyde resin-modified phenol resin-type cyanate ester resins, biphenyl-modified novolac-type cyanate ester resins, anthracene-type cyanate ester resins, and the like. These may be used alone or in combination of two or more.

  Among these cyanate ester resins, bisphenol A-type cyanate ester resins, bisphenol F-type cyanate ester resins, bisphenol E-type cyanate ester resins, and polyhydroxynaphthalene-type cyanate ester resins are particularly preferred in that a cured product having excellent heat resistance can be obtained. Naphthalene ether type cyanate ester resin and novolak type cyanate ester resin are preferably used, and dicyclopentadiene-phenol addition reaction type cyanate ester resin is preferable in that a cured product having excellent dielectric properties can be obtained.

  Examples of the maleimide compound include various compounds represented by any of the following structural formulas (i) to (iii).

  In the formula (Z1), R is an n-valent organic group, x and y are each a hydrogen atom, a halogen atom, an alkyl group, or an aryl group, and n is an integer of 1 or more. )

  In the formula (Z2), R is any one of a hydrogen atom, an alkyl group, an aryl group, an aralkyl group, a halogen atom, a hydroxyl group, and an alkoxy group, n is an integer of 1 to 3, and m is an average of 0 to 0. 10.

  In the formula (Z3), R is any one of a hydrogen atom, an alkyl group, an aryl group, an aralkyl group, a halogen atom, a hydroxyl group, and an alkoxy group, n is an integer of 1 to 3, and m is an average of 0 to 0. 10.

  Although there is no restriction | limiting in particular as said active ester resin, Generally ester group with high reaction activity, such as phenol ester, thiophenol ester, N-hydroxyamine ester, ester of heterocyclic hydroxy compound, is in 1 molecule. A compound having two or more is preferably used. The active ester resin is preferably obtained by a condensation reaction between a carboxylic acid compound and / or a thiocarboxylic acid compound and a hydroxy compound and / or a thiol compound. In particular, from the viewpoint of improving heat resistance, an active ester resin obtained from a carboxylic acid compound or a halide thereof and a hydroxy compound is preferred, and an active ester resin obtained from a carboxylic acid compound or a halide thereof and a phenol compound and / or a naphthol compound is preferred. More preferred. Examples of the carboxylic acid compound include benzoic acid, acetic acid, succinic acid, maleic acid, itaconic acid, phthalic acid, isophthalic acid, terephthalic acid, pyromellitic acid, and the like, or a halide thereof. Examples of the phenol compound or naphthol compound include hydroquinone, resorcin, bisphenol A, bisphenol F, bisphenol S, dihydroxydiphenyl ether, phenolphthalein, methylated bisphenol A, methylated bisphenol F, methylated bisphenol S, phenol, o-cresol, m -Cresol, p-cresol, catechol, α-naphthol, α-naphthol, 1,5-dihydroxynaphthalene, 1,6-dihydroxynaphthalene, 2,6-dihydroxynaphthalene, dihydroxybenzophenone, trihydroxybenzophenone, tetrahydroxybenzophenone, phloroglucin , Benzenetriol, dicyclopentadiene-phenol addition resin, and the like.

  Specific examples of the active ester resin include an active ester resin containing a dicyclopentadiene-phenol addition structure, an active ester resin containing a naphthalene structure, an active ester resin that is an acetylated product of phenol novolac, and an activity that is a benzoylated product of phenol novolac. An ester resin or the like is preferable, and an active ester resin including a dicyclopentadiene-phenol addition structure and an active ester resin including a naphthalene structure are more preferable because they are excellent in improving peel strength. More specifically, examples of the active ester resin containing a dicyclopentadiene-phenol addition structure include compounds represented by the following structural formula (iv).

  In formula (d), R is a phenyl group or a naphthyl group, u represents 0 or 1, and n is 0.05 to 2.5 on the average of repeating units. From the viewpoint of reducing the dielectric loss tangent of the cured resin material and improving the heat resistance, R is preferably a naphthyl group, u is preferably 0, and n is preferably 0.25 to 1.5.

  Curing of the curable resin composition of the present invention proceeds even without a catalyst, but a catalyst can be used in combination. These catalysts include tertiary amine compounds such as imidazole and dimethylaminopyridine; phosphorus compounds such as triphenylphosphine; boron trifluoride amine complexes such as boron trifluoride and boron trifluoride monoethylamine complexes; thiodipropionic acid Examples thereof include organic acid compounds such as: benzoxazine compounds such as thiodiphenol benzoxazine and sulfonyl benzoxazine; sulfonyl compounds; phenolic hydroxyl group-containing compounds. Examples of the phenolic hydroxyl group-containing compound include phenol, cresol, dihydroxybenzene, bisphenol A type, bisphenol F type, bisphenol E type, bisphenol S type, bisphenol sulfide, dihydroxyphenylene ether, phenol novolac resin, cresol novolac resin, and aromatic. Hydrocarbon formaldehyde resin modified phenol resin, naphthylene ether resin, dicyclopentadiene phenol addition resin, phenol aralkyl resin, naphthol aralkyl resin, trimethylol methane resin, tetraphenylol ethane resin, naphthol novolak resin, naphthol-phenol co-condensed novolak Resin, naphthol-cresol co-condensed novolak resin, biphenyl modified phenolic resin Polyphenol compound with a polyol nucleus linked), biphenyl-modified naphthol resin (polyvalent naphthol compound with a phenol nucleus linked by a bismethylene group), aminotriazine-modified phenol resin (a compound with a phenol nucleus linked with melamine, benzoguanamine, etc.) Valent phenol compound) and the like. These may be used alone or in combination of two or more. It is preferable that the addition amount of these catalysts is 0.001-15 mass parts in 100 mass parts of curable resin compositions.

  When the curable resin composition of the present invention is used for applications requiring high flame retardancy such as printed wiring board applications, a non-halogen flame retardant containing substantially no halogen atoms may be blended.

  Examples of the non-halogen flame retardant include a phosphorus flame retardant, a nitrogen flame retardant, a silicone flame retardant, an inorganic flame retardant, an organic metal salt flame retardant, and the like. It is not intended to be used alone, and a plurality of the same type of flame retardants may be used, or different types of flame retardants may be used in combination.

  As the phosphorus flame retardant, either inorganic or organic can be used. Examples of the inorganic compounds include red phosphorus, monoammonium phosphate, diammonium phosphate, triammonium phosphate, ammonium phosphates such as ammonium polyphosphate, and inorganic nitrogen-containing phosphorus compounds such as phosphate amide. .

  The red phosphorus is preferably subjected to a surface treatment for the purpose of preventing hydrolysis and the like. Examples of the surface treatment method include (i) magnesium hydroxide, aluminum hydroxide, zinc hydroxide, water A method of coating with an inorganic compound such as titanium oxide, bismuth oxide, bismuth hydroxide, bismuth nitrate or a mixture thereof; (ii) an inorganic compound such as magnesium hydroxide, aluminum hydroxide, zinc hydroxide, titanium hydroxide; and A method of coating with a mixture of a thermosetting resin such as a phenol resin, (iii) thermosetting of a phenol resin or the like on a coating of an inorganic compound such as magnesium hydroxide, aluminum hydroxide, zinc hydroxide, or titanium hydroxide For example, a method of double coating with a resin may be used.

  The organic phosphorus compounds include, for example, general-purpose organic phosphorus compounds such as phosphate ester compounds, phosphonic acid compounds, phosphinic acid compounds, phosphine oxide compounds, phosphorane compounds, organic nitrogen-containing phosphorus compounds, and 9,10-dihydro -9-oxa-10-phosphaphenanthrene-10-oxide, 10- (2,5-dihydroxyphenyl) -10H-9-oxa-10-phosphaphenanthrene-10-oxide, 10- (2,7- And cyclic organic phosphorus compounds such as dihydrooxynaphthyl) -10H-9-oxa-10-phosphaphenanthrene-10-oxide and derivatives obtained by reacting them with compounds such as phenol resins and phenol resins.

  The amount of these phosphorus-based flame retardants is preferably, for example, in the range of 0.1 to 2.0 parts by weight in the case of using red phosphorus in 100 parts by weight of the curable resin composition. Is preferably used in the range of 0.1 to 10.0 parts by mass, and more preferably in the range of 0.5 to 6.0 parts by mass.

  In addition, when using the phosphorous flame retardant, the phosphorous flame retardant may be used in combination with hydrotalcite, magnesium hydroxide, boric compound, zirconium oxide, black dye, calcium carbonate, zeolite, zinc molybdate, activated carbon, etc. Good.

  Examples of the nitrogen-based flame retardant include triazine compounds, cyanuric acid compounds, isocyanuric acid compounds, phenothiazines, and the like, and triazine compounds, cyanuric acid compounds, and isocyanuric acid compounds are preferable.

  Examples of the triazine compound include melamine, acetoguanamine, benzoguanamine, melon, melam, succinoguanamine, ethylene dimelamine, melamine polyphosphate, triguanamine, and the like, for example, sulfuric acid such as guanylmelamine sulfate, melem sulfate, and melam sulfate. Examples thereof include aminotriazine compounds, aminotriazine-modified phenol resins, and aminotriazine-modified phenol resins that are further modified with tung oil, isomerized linseed oil, and the like.

  Examples of the cyanuric acid compound include cyanuric acid and cyanuric acid melamine.

  The blending amount of the nitrogen-based flame retardant is preferably blended in a range of 0.05 to 10 parts by weight, for example, in a range of 0.1 to 5 parts by weight in 100 parts by weight of the curable resin composition. It is more preferable.

  Moreover, when using the said nitrogen-type flame retardant, you may use together a metal hydroxide, a molybdenum compound, etc.

  The silicone flame retardant is not particularly limited as long as it is an organic compound containing a silicon atom, and examples thereof include silicone oil, silicone rubber, and silicone resin.

  It is preferable to mix | blend the compounding quantity of the said silicone type flame retardant in the range of 0.05-20 mass parts in 100 mass parts of curable resin compositions, for example. Moreover, when using the said silicone type flame retardant, you may use a molybdenum compound, an alumina, etc. together.

  Examples of the inorganic flame retardant include metal hydroxide, metal oxide, metal carbonate compound, metal powder, boron compound, and low melting point glass.

  Examples of the metal hydroxide include aluminum hydroxide, magnesium hydroxide, dolomite, hydrotalcite, calcium hydroxide, barium hydroxide, and zirconium hydroxide.

  Examples of the metal oxide include zinc molybdate, molybdenum trioxide, zinc stannate, tin oxide, aluminum oxide, iron oxide, titanium oxide, manganese oxide, zirconium oxide, zinc oxide, molybdenum oxide, cobalt oxide, bismuth oxide, Examples thereof include chromium oxide, nickel oxide, copper oxide, and tungsten oxide.

  Examples of the metal carbonate compound include zinc carbonate, magnesium carbonate, calcium carbonate, barium carbonate, basic magnesium carbonate, aluminum carbonate, iron carbonate, cobalt carbonate, and titanium carbonate.

  Examples of the metal powder include aluminum, iron, titanium, manganese, zinc, molybdenum, cobalt, bismuth, chromium, nickel, copper, tungsten, and tin.

  Examples of the boron compound include zinc borate, zinc metaborate, barium metaborate, boric acid, and borax.

Examples of the low-melting-point glass include Sheepley (Bokusui Brown), hydrated glass SiO ₂ —MgO—H ₂ O, PbO—B ₂ O ₃ system, ZnO—P ₂ O ₅ —MgO system, and P ₂ O. Glass forms such as _5- B ₂ O ₃ —PbO—MgO, P—Sn—O—F, PbO—V ₂ O ₅ —TeO ₂ , Al ₂ O ₃ —H ₂ O, lead borosilicate, etc. A compound can be mentioned.

  The blending amount of the inorganic flame retardant is preferably blended in the range of 0.05 to 20 parts by weight, for example, in the range of 0.5 to 15 parts by weight in 100 parts by weight of the curable resin composition. It is more preferable.

  Examples of the organic metal salt flame retardant include ferrocene, acetylacetonate metal complex, organic metal carbonyl compound, organic cobalt salt compound, organic sulfonic acid metal salt, metal atom and aromatic compound or heterocyclic compound. And the like.

  It is preferable to mix | blend the compounding quantity of the said organometallic salt type flame retardant in the range of 0.005-10 mass parts in 100 mass parts of curable resin compositions, for example.

  The curable resin composition of this invention can mix | blend an inorganic filler as needed. Examples of the inorganic filler include fused silica, crystalline silica, alumina, silicon nitride, and aluminum hydroxide. When particularly increasing the blending amount of the inorganic filler, it is preferable to use fused silica. The fused silica can be used in either a crushed shape or a spherical shape. However, in order to increase the blending amount of the fused silica and suppress an increase in the melt viscosity of the molding material, it is preferable to mainly use a spherical shape. In order to further increase the blending amount of the spherical silica, it is preferable to appropriately adjust the particle size distribution of the spherical silica. The filling rate is preferably high in consideration of flame retardancy, and is particularly preferably 20% by mass or more based on the total mass of the curable resin composition. Moreover, when using for uses, such as an electrically conductive paste, electroconductive fillers, such as silver powder and copper powder, can be used.

  The curable resin composition of the present invention is optionally provided with reinforcing fibers such as glass, quartz, carbon, oriented fibers, and synthetic fibers in the normal form of short fibers, staple fibers, twisted yarns, fabrics or mats, if necessary. (Keflar, Nomex), natural fibers such as flax, burlap, sisal hemp, hemp hemp: silane coupling agent: mold release agent: pigment: dye: emulsifier and various other compounding agents can be added.

  The curable resin composition of the present invention is cured by heating and can be easily made into a cured product. Specifically, it is obtained by uniformly mixing the above-described components, and is easily cured by heating the curable resin composition at a temperature of about 100 ° C. or higher, preferably 140 to 220 ° C. It can be.

  The curable resin composition of the present invention is a known process for thermosetting resins such as phenol formaldehyde resins or epoxy resins, such as prepreg hot pressing, SMC (sheet molding compound): or molding: casting: filament winding. It is preferable to process using an injection technique or a vacuum impregnation (RTM, VaRTM) method, and since it is excellent in heat resistance, heat decomposition resistance, flame retardancy and dielectric properties in a cured product, Insulating materials for circuit boards such as resin compositions for flexible wiring boards, interlayer insulating materials for build-up boards, semiconductor sealing materials, conductive pastes, adhesive films for build-up, resin casting materials, adhesives, FRP materials, etc. It can be suitably used as various materials.

  When applied to a semiconductor sealing material, the curable resin composition is sufficiently mixed with a compounding agent such as an inorganic filler using an extruder, kneader, roll or the like as necessary until uniform. A semiconductor sealing material can be manufactured by melt-mixing. At that time, fused silica is usually used as the inorganic filler, but when used as a high thermal conductive semiconductor encapsulant for power transistors and power ICs, crystalline silica, alumina, nitridation having higher thermal conductivity than fused silica. High filling such as silicon, or fused silica, crystalline silica, alumina, silicon nitride, or the like may be used. The content of the inorganic filler is preferably in the range of 30 to 95 parts by mass per 100 parts by mass of the curable resin composition, and among them, improvement in flame retardancy, moisture resistance and solder crack resistance, and linear expansion In order to reduce the coefficient, the amount is more preferably 70 to 95 parts by mass, and still more preferably 80 to 95 parts by mass.

  When applied to circuit board applications, the varnish formed by adding an organic solvent to the curable resin composition of the present invention is formed into a plate shape, laminated with copper foil, and heated and pressed to form a circuit board. Can be manufactured. In addition, when applying to hard printed wiring board applications, a prepreg is obtained by impregnating a reinforcing base material with a varnish obtained by adding an organic solvent to a curable resin composition and semi-curing it, and then overlaying a copper foil thereon. And can be manufactured by a method of thermocompression bonding.

  The organic solvent used when varnishing the curable resin composition of the present invention is preferably a polar solvent having a boiling point of 160 ° C. or lower, such as methyl ethyl ketone, acetone, 1-methoxy-2-propanol, etc. It is preferable to use in the ratio from which the non volatile matter of a conductive resin composition will be 40-80 mass%. Examples of the reinforcing base material used for the printed wiring board include paper, glass cloth, glass nonwoven fabric, aramid paper, aramid cloth, glass mat, and glass roving cloth. More specifically, the varnish-like curable resin composition described above is first heated at a heating temperature corresponding to the solvent type used, preferably 50 to 170 ° C. to obtain a cured prepreg. obtain. At this time, the mass ratio of the curable resin composition to be used and the reinforcing substrate is not particularly limited, but it is usually preferable that the resin content in the prepreg is 20 to 60 mass%. Next, the prepreg obtained as described above is laminated by a conventional method, and a copper foil is appropriately stacked, and then subjected to thermocompression bonding at 170 to 250 ° C. for 10 minutes to 3 hours under a pressure of 1 to 10 MPa, A target circuit board can be obtained.

In order to produce a flexible wiring board from the curable resin composition of the present invention, a curable resin composition containing an organic solvent is applied to an electrical insulating film using a coating machine such as a reverse roll coater or a comma coater. Subsequently, it heats for 1 to 15 minutes at 60-170 degreeC using a heater, volatilizes a solvent, and makes curable resin composition B-stage. Next, the metal foil is thermocompression bonded to the resin layer using a heating roll or the like. At that time, the pressure is preferably ^{2 to} 200 N / cm ² and the pressure is 40 to 200 ° C. If sufficient adhesive performance can be obtained, the process may be completed here. However, when complete curing is required, it is preferably post-cured at 100 to 200 ° C. for 1 to 24 hours. The thickness of the resin layer after finally curing is preferably in the range of 5 to 100 μm.

  In order to produce a build-up film from the curable resin composition of the present invention, for example, a curable resin composition appropriately blended with rubber, filler or the like is spray-coated on a substrate such as a wiring board on which a circuit is formed, After applying using a curtain coating method or the like, it is cured. Then, after drilling a predetermined through-hole part etc. as needed, it treats with a roughening agent, forms the unevenness | corrugation by washing the surface with hot water, and metal-treats, such as copper. As the plating method, electroless plating or electrolytic plating treatment is preferable, and examples of the roughening agent include an oxidizing agent, an alkali, and an organic solvent. Such operations are sequentially repeated as desired, and a build-up substrate can be obtained by alternately building up and forming a resin insulating layer and a conductor layer having a predetermined circuit pattern. However, the through-hole portion is formed after the outermost resin insulating layer is formed. Moreover, a roughened surface is formed by heat-pressing a copper foil with a resin obtained by semi-curing a curable resin composition on a copper foil onto a wiring board on which a circuit is formed at 170 to 250 ° C. It is also possible to produce a build-up substrate by omitting this process.

  The method for producing an adhesive film for build-up from the curable resin composition of the present invention is, for example, applying a diluted curable resin composition of the present invention by adding an organic solvent on a support film, and The method of forming and making it the adhesive film for multilayer printed wiring boards is mentioned.

  Examples of the organic solvent used in this case include ketone solvents such as acetone, methyl ethyl ketone, and cyclohexanone, acetate solvents such as ethyl acetate, butyl acetate, cellosolve acetate, propylene glycol monomethyl ether acetate, and carbitol acetate, ethanol, propanol, butanol, and the like. Alcohol solvents, cellosolve, carbitol solvents such as butyl carbitol, dimethylformamide, dimethylacetamide, N-methylpyrrolidone, etc. are used, and the curable resin composition should be used in a ratio of 30 to 60% by mass. Is preferred.

  The adhesive film comprising the curable resin composition of the present invention is softened under the lamination temperature condition (usually 70 ° C. to 140 ° C.) in the vacuum laminating method, and simultaneously with the lamination of the circuit board, via holes or through holes existing in the circuit board. It is important to show fluidity (resin flow) that can be filled with resin, and it is preferable to blend the above-described components so as to exhibit such characteristics.

  Here, the diameter of the through hole of the multilayer printed wiring board is usually 0.1 to 0.5 mm, and the depth is usually 0.1 to 1.2 mm. It is usually preferable to allow resin filling in this range. When laminating both surfaces of the circuit board, it is desirable to fill about 1/2 of the through hole.

  Specifically, the method for producing the adhesive film described above is, after preparing the varnish-like curable resin composition of the present invention, applying the varnish-like curable resin composition to the surface of the support film, Further, it can be produced by drying the organic solvent by heating or blowing hot air to form the layer (γ) of the curable resin composition.

  The thickness of the layer (γ) to be formed is usually not less than the thickness of the conductor layer. Since the thickness of the conductor layer included in the circuit board is usually in the range of 5 to 70 μm, the thickness of the resin layer is preferably 10 to 100 μm.

  In addition, the said layer ((gamma)) may be protected with the protective film mentioned later. By protecting with a protective film, it is possible to prevent dust and the like from adhering to the resin assembly layer surface and scratches.

  The above-mentioned support film and protective film are made of polyolefin such as polyethylene, polypropylene and polyvinyl chloride, polyethylene terephthalate (hereinafter sometimes abbreviated as “PET”), polyester such as polyethylene naphthalate, polycarbonate, polyimide, and further. Examples thereof include metal foil such as pattern paper, copper foil, and aluminum foil. In addition, the support film and the protective film may be subjected to a release treatment in addition to the mud treatment and the corona treatment.

  Although the thickness of a support film is not specifically limited, Usually, it is 10-150 micrometers, Preferably it is used in 25-50 micrometers. Moreover, it is preferable that the thickness of a protective film shall be 1-40 micrometers.

  The above support film is peeled off after being laminated on the circuit board or after forming the insulating layer by heat curing. If the support film is peeled after the adhesive film is heat-cured, adhesion of dust and the like in the curing process can be prevented. In the case of peeling after curing, the support film is usually subjected to a release treatment in advance.

  Next, a method for producing a multilayer printed wiring board using the adhesive film obtained as described above is, for example, when the layer (γ) is protected with a protective film, after peeling these layers ( Lamination is performed, for example, by a vacuum laminating method on one side or both sides of the circuit board so that γ) is in direct contact with the circuit board. The laminating method may be a batch method or a continuous method using a roll. Further, the adhesive film and the circuit board may be heated (preheated) as necessary before lamination.

The laminating conditions are preferably a pressure bonding temperature (laminating temperature) of 70 to 140 ° C., a pressure bonding pressure of preferably 1 to 11 kgf / cm ² (9.8 × 10 ^{4 to} 107.9 × 10 ⁴ N / m 2), Lamination is preferably performed under reduced pressure with an air pressure of 20 mmHg (26.7 hPa) or less.

  When the curable resin composition of the present invention is used as a conductive paste, for example, a method of dispersing fine conductive particles in a curable resin composition to form a composition for an anisotropic conductive film, which is liquid at room temperature. Examples thereof include a paste resin composition for circuit connection and an anisotropic conductive adhesive.

  The curable resin composition of the present invention can also be used as a resist ink. In this case, a vinyl monomer having an ethylenically unsaturated double bond and a cationic polymerization catalyst as a curing agent are blended in the curable resin composition, and further, a pigment, talc, and filler are added to form a resist ink composition. Then, after apply | coating on a printed circuit board by a screen printing system, the method of setting it as a resist ink hardened | cured material is mentioned. Since the polyarylene ether resin alone can cause a curing reaction, in the curable resin composition of the present invention, the polyarylene aer resin may be used alone or in combination with other resins. May be.

  Next, the present invention will be specifically described with reference to Examples and Comparative Examples. In the following, “parts” and “%” are based on mass unless otherwise specified. GPC, IR, and MS were measured under the following conditions.

GPC: Measurement conditions are as follows.
Measuring device: “HLC-8220 GPC” manufactured by Tosoh Corporation
Column: Guard column “HXL-L” manufactured by Tosoh Corporation
+ "TSK-GEL G2000HXL" manufactured by Tosoh Corporation
+ "TSK-GEL G2000HXL" manufactured by Tosoh Corporation
+ Tosoh Corporation “TSK-GEL G3000HXL”
+ Tosoh Corporation “TSK-GEL G4000HXL”
Detector: RI (differential refractometer)
Data processing: “GPC-8020 Model II version 4.10” manufactured by Tosoh Corporation
Measurement conditions: Column temperature 40 ° C
Developing solvent Tetrahydrofuran
Flow rate: 1.0 ml / min Standard: The following monodisperse polystyrene having a known molecular weight was used in accordance with the measurement manual of “GPC-8020 Model II version 4.10”.
(Polystyrene used)
“A-500” manufactured by Tosoh Corporation
"A-1000" manufactured by Tosoh Corporation
"A-2500" manufactured by Tosoh Corporation
"A-5000" manufactured by Tosoh Corporation
“F-1” manufactured by Tosoh Corporation
"F-2" manufactured by Tosoh Corporation
“F-4” manufactured by Tosoh Corporation
“F-10” manufactured by Tosoh Corporation
“F-20” manufactured by Tosoh Corporation
“F-40” manufactured by Tosoh Corporation
“F-80” manufactured by Tosoh Corporation
“F-128” manufactured by Tosoh Corporation
Sample: A 1.0 mass% tetrahydrofuran solution filtered in terms of resin solids and filtered through a microfilter (50 μl).

<IR measurement device>
The following apparatus was used as an IR measurement apparatus.
Equipment: “FT / IR-550” manufactured by JASCO Corporation

<MS measuring device>
The following apparatus was used as the MS measurement apparatus.
Apparatus: Double convergence type mass spectrometer AX505H (FD505H) manufactured by JEOL Ltd.

Example 1 Production of benzoxazine resin (A-1) In a flask equipped with a thermometer, a dropping funnel, a condenser tube, a fractionating tube and a stirrer, 160 g (1.0 mol) of 2,7-dihydroxynaphthalene, 1, 158 g (1.0 mol) of 4-naphthoquinone, 6 g of paratoluenesulfonic acid, and 318 g of methyl isobutyl ketone were charged, and the temperature was raised from room temperature to 120 ° C. with stirring. After reaching 120 ° C., the reaction was allowed to stir for 3 hours. After completion of the reaction, the reaction mixture was neutralized and washed 3 times with 200 g of water. Then, it heated to 150 degreeC and dried under reduced pressure, and obtained 300 g of phenol resins (A). The GPC chart of the obtained phenol resin (A) is shown in FIG. The hydroxyl equivalent of the phenol resin (A) was 137 g / eq. The content of the component corresponding to the dinaphthofuran compound represented by the following structural formula (a) calculated from the GPC chart is 55.3%, and the value of k represented by the following structural formula (b) is 1. The content of the component corresponding to the compound corresponding to the nucleophilic phenol compound was 9.7%, and the content of the component corresponding to the trinuclear phenol compound represented by the following structural formula (c) was 22.0%. It was.

［ｘ、ｙはナフタレン環との結合点を示し、フラン環を形成するように互いに隣接する炭素に結合することを表す。］

[X and y represent a bonding point with a naphthalene ring, and represent bonding to carbons adjacent to each other so as to form a furan ring. ]

Next, 93.1 g (1.0 mol) of aniline and 137.0 g of phenol resin (A) were passed through a four-necked flask equipped with a dropping funnel, thermometer, stirring device, heating device, and cooling reflux tube. (Hydroxyl group equivalent: 1.0 equivalent) was dissolved in 400 g of toluene, 143 g (2.0 mol) of 42% formaldehyde aqueous solution was added, the temperature was raised to 80 ° C. with stirring, and the reaction was allowed to proceed at 80 ° C. for 5 hours. It was. After the reaction, it was transferred to a separatory funnel and the aqueous layer was removed. Thereafter, the solvent was removed from the organic layer under heating and reduced pressure to obtain 167 g of a benzoxazine resin. The IR spectrum showed an absorption of 948 cm ⁻¹ derived from the oxazine ring, and the mass spectrum showed a peak such as 535. Thus, it was confirmed that the target benzoxazine resin (A-1) was obtained.

Example 2 Production of benzoxazine resin (B-1) In a flask equipped with a thermometer, a dropping funnel, a condenser tube, a fractionating tube, and a stirrer, 160 g (1.0 mol) of 2,7-dihydroxynaphthalene, 1, 158 g (1.0 mol) of 4-naphthoquinone, 6 g of paratoluenesulfonic acid, and 333 g of isopropyl alcohol were charged, and the temperature was raised from room temperature to 80 ° C. with stirring. After reaching 80 ° C., the reaction was allowed to stir for 3 hours. After completion of the reaction, the reaction mixture was neutralized and washed 3 times with 200 g of water. Then, it heated to 150 degreeC and dried under reduced pressure, and obtained 295g of phenol resins (B). The GPC chart of the obtained phenol resin (B) is shown in FIG. The hydroxyl equivalent of the phenol resin was 119 g / eq. Further, the content of the component corresponding to the dinaphthofuran compound represented by the structural formula (a) calculated from the GPC chart is 50.2%, and the value of k represented by the structural formula (b) is 1. The content of the component corresponding to the compound corresponding to the nucleophilic phenol compound was 14.8%, and the content of the component corresponding to the trinuclear phenol compound represented by the structural formula (c) was 24.2%. It was.

Next, while flowing nitrogen gas through a four-necked flask equipped with a dropping funnel, thermometer, stirring device, heating device, and cooling reflux tube, 93.1 g (1.0 mol) of aniline and 119 g of phenol resin (B) (hydroxyl group) 1.0 equivalent) was dissolved in 400 g of toluene, 143 g (2.0 mol) of a 42% formaldehyde aqueous solution was added, the temperature was raised to 80 ° C. with stirring, and the mixture was reacted at 80 ° C. for 5 hours. After the reaction, it was transferred to a separatory funnel and the aqueous layer was removed. Thereafter, the solvent was removed from the organic layer under heating and reduced pressure to obtain 152 g of a benzoxazine resin. The IR spectrum showed an absorption of 948 cm ⁻¹ derived from the oxazine ring, and the mass spectrum showed a peak such as 535. Thus, it was confirmed that the target benzoxazine resin (B-1) was obtained.

Example 3 Production of benzoxazine resin (C-1) Into a flask equipped with a thermometer, a dropping funnel, a condenser tube, a fractionating tube and a stirrer, 160 g (1.0 mol) of 1,5-dihydroxynaphthalene, 1, 158 g (1.0 mol) of 4-naphthoquinone, 6 g of paratoluenesulfonic acid, and 333 g of isopropyl alcohol were charged, and the temperature was raised from room temperature to 80 ° C. with stirring. After reaching 80 ° C., the reaction was allowed to stir for 3 hours. After completion of the reaction, the reaction mixture was neutralized and washed 3 times with 200 g of water. Then, it heated to 150 degreeC and dried under reduced pressure, and obtained 292g of phenol resins (C). The GPC chart of the obtained phenol resin (C) is shown in FIG. The hydroxyl equivalent of the phenol resin was 132 g / eq. The content of the component corresponding to the dinaphthofuran compound calculated from the GPC chart and represented by the structural formula (a) was 24.1%.

Subsequently, 93.1 g (1.0 mol) of aniline and 132 g of phenol resin (C) (hydroxyl group) were passed through a four-necked flask equipped with a dropping funnel, thermometer, stirring device, heating device, and cooling reflux tube. 1.0 equivalent) was dissolved in 400 g of toluene, 143 g (2.0 mol) of a 42% formaldehyde aqueous solution was added, the temperature was raised to 80 ° C. with stirring, and the mixture was reacted at 80 ° C. for 5 hours. After the reaction, it was transferred to a separatory funnel and the aqueous layer was removed. Thereafter, the solvent was removed from the organic layer under heating and reduced pressure to obtain 177 g of a benzoxazine resin. The IR spectrum showed an absorption of 948 cm ⁻¹ derived from the oxazine ring, and the mass spectrum showed a peak such as 535. Thus, it was confirmed that the target benzoxazine resin (C-1) was obtained.

Examples 4-6 Manufacture of a composition and hardened | cured material The benzoxazine resin (A-1) obtained in Examples 1-3, (B-1), (C-1), and a phenol novolak resin (DIC Corporation) “TD-2131”) and fused silica (“FB3SDC” manufactured by Denki Kagaku Co., Ltd.) are mixed as shown in Table 1, molded at a temperature of 200 ° C. for 10 minutes with a press, and then at a temperature of 200 ° C. After curing for 5 hours, a cured product having a thickness of 0.8 mm was obtained.

Comparative Example 1 Production of Composition and Cured Product A benzoxazine compound (manufactured by Huntsman, reaction product of bisphenol F, formalin and aniline (shown as “MT35700” in the table)) and a phenol novolac resin (manufactured by DIC Corporation “TD” -2131 ") and fused silica (" FB3SDC "manufactured by Electrochemical Co., Ltd.) are mixed as shown in Table 1 and molded at a temperature of 200 ° C for 10 minutes with a press, and then 5 at a temperature of 200 ° C. After time, it was cured to obtain a cured product having a thickness of 0.8 mm.

  About the hardened | cured material obtained in Examples 4-6 and the comparative example 1, the glass transition point, the thermal decomposition resistance, a dielectric constant, a dielectric loss tangent, and the flame retardance were measured. The results are shown in Table 1, and the measurement method is shown below.

<Measurement of glass transition point>
From the cured product obtained above, a cured product having a thickness of 0.8 mm was cut into a size of 5 mm in width and 54 mm in length. Using this test piece 1 with a viscoelasticity measuring device (DMA: solid viscoelasticity measuring device “RSAII” manufactured by Rheometric Co., Ltd., rectangular tension method: frequency 1 HZ, heating rate 3 ° C./min) Temperature (the largest rate of change in tan δ) was measured as the glass transition point.

<Measurement of thermal decomposition resistance>
After holding the test piece 1 at 250 ° C. for 72 hours, the mass reduction rate when compared with the initial mass was measured.

<Measurement of dielectric constant and tangent>
In accordance with JIS-C-6481, the impedance material analyzer “HP4291B” manufactured by Agilent Technologies, Inc. was used to dry the test piece 1 at 1 GHZ after being stored in a room at 23 ° C. and 50% humidity for 24 hours. The dielectric constant and tangent were measured.
<Measurement of flame retardancy>
From the cured product obtained above, a cured product having a thickness of 0.8 mm was cut into a size having a width of 12.7 mm and a length of 127 mm. About this test piece 2, the measurement of the combustion test was performed based on the UL-94 test method. The combustion test was performed using five test pieces 2 each.

Claims (14)

  A diarylene [b, d] furan structure, at least one of the two arylene groups forming the diarylene [b, d] furan structure has a naphthylene skeleton, and the two arylene groups are Both are benzoxazine compounds obtained by reacting a phenolic compound having a hydroxyl group on the aromatic ring with a monoamine compound and formaldehyde.   Carbon to which an oxygen atom forming a furan ring of the diarylene [b, d] furan bond is bonded to at least one of the two arylene groups forming the diarylene [b, d] furan structure of the phenol compound. The benzoxazine compound according to claim 1, which has a hydroxyl group at the para position of the atom. The benzoxazine compound according to claim 2, wherein the phenol compound has a molecular structure represented by the following structural formula (I) or the following structural formula (II).

[In formulas (I) and (II), each R ¹ independently represents a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, an alkoxy group having 1 to 4 carbon atoms, an aryl group, or an aralkyl group. Either. Ar ¹ is a structural moiety represented by the following structural formula (i), and Ar ² is a structural moiety represented by the following structural formula (i) or (ii). ]

[In the formulas (i) and (ii), each R ² is independently an alkyl group having 1 to 4 carbon atoms, an alkoxy group having 1 to 4 carbon atoms, an aryl group, or an aralkyl group. m is an integer of 0 to 4, and n is an integer of 0 to 3. When m or n is 2 or more, R ² may be the same or different from each other. x and y each represent a bonding point with the naphthalene ring and represent that they are bonded to adjacent carbon atoms of the naphthalene ring so as to form a furan ring with the oxygen atom. In formula (i), R ² and a hydroxyl group bonded to the naphthalene ring may be bonded to any aromatic ring among the aromatic rings constituting the naphthalene ring. ] The benzoxazine compound according to claim 3, wherein the phenol compound has a molecular structure represented by any one of the following structural formulas (1) to (4).

[In the formulas (1) to (4), each R ² is independently an alkyl group having 1 to 4 carbon atoms, an alkoxy group having 1 to 4 carbon atoms, an aryl group, or an aralkyl group. , M is an integer from 0 to 4, and n is an integer from 0 to 3. When m or n is 2 or more, R ² may be the same or different from each other. x and y each represent a bonding point with the naphthalene ring and represent that they are bonded to adjacent carbon atoms of the naphthalene ring so as to form a furan ring with the oxygen atom. In the formulas (1) to (3), R ² bonded to the naphthalene ring and the hydroxyl group bonded to the naphthalene ring linked to the R ² are each an aromatic ring constituting the naphthalene ring. It may be bonded to an aromatic ring. ]   A benzoxazine resin containing the benzoxazine compound according to any one of claims 1 to 4.   A step of obtaining a phenol compound by reacting a compound (Q) having a quinone structure in the molecular structure with a compound (P) having a phenolic hydroxyl group in the molecular structure in the presence of an acid catalyst; A step of reacting a phenol compound with a monoamine compound and formaldehyde, wherein at least one of the compound (Q) having the quinone structure or the compound (P) having a phenolic hydroxyl group in the molecular structure is intramolecular A method for producing a benzoxazine compound having a naphthalene ring.   A curable resin composition comprising the benzoxazine compound according to any one of claims 1 to 4 or the benzoxazine resin according to claim 5 as an essential component.   A cured product obtained by curing the curable resin composition according to claim 7.   An FRP material comprising the curable resin composition according to claim 7.   A semiconductor package comprising the curable resin composition according to claim 7 and an inorganic filler, wherein the content of the inorganic filler is in the range of 30 to 95 parts by mass per 100 parts by mass of the curable resin composition. Stop material.   A varnish obtained by adding an organic solvent to the curable resin composition according to claim 7.   A circuit board obtained by laminating the varnish according to claim 11 in a plate shape with a copper foil and molding by heating and pressing.   A prepreg obtained by impregnating a varnish according to claim 11 into a reinforcing base material and then semi-curing it.   The buildup film formed by making it harden | cure after apply | coating the curable resin composition of Claim 7 on a board | substrate.

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