WO2020054218A1 - Benzoxazine compound, curable resin composition, adhesive, adhesive film, cured object, circuit board, interlayer dielectric material, and multilayered printed wiring board - Google Patents

Abstract

A purpose of the present invention is to provide a benzoxazine compound usable in a curable resin composition which has excellent pliability before curing and has excellent dielectric properties after curing. Another purpose of the present invention is to provide: a curable resin composition containing the benzoxazine compound; and an adhesive, adhesive film, cured object, circuit board, interlayer dielectric material, and multilayered printed wiring board each comprising or obtained using the curable resin composition. The benzoxazine compound of the present invention includes, in the molecule, both a benzoxazine ring and a diamine residue having a C₄ or higher aliphatic skeleton and/or a triamine residue having a C₄ or higher aliphatic skeleton.

Description

Benzoxazine compounds, curable resin compositions, adhesives, adhesive films, cured products, circuit boards, interlayer insulating materials, and multilayer printed wiring boards

The present invention relates to a benzoxazine compound that can be used for a curable resin composition having excellent flexibility before curing and having excellent dielectric properties after curing. The present invention also provides a curable resin composition containing the benzoxazine compound, an adhesive, an adhesive film, a cured product, a circuit board, an interlayer insulating material, and a multilayer printed wiring board using the curable resin composition. About.

2. Description of the Related Art Curable resins, such as epoxy resins, which have low shrinkage and are excellent in adhesion, insulation, and chemical resistance, are used in many industrial products. In particular, a curable resin composition used for an interlayer insulating material or the like of a printed wiring board requires dielectric properties such as a low dielectric constant and a low dielectric loss tangent. As curable resin compositions having such excellent dielectric properties, for example, Patent Documents 1 and 2 disclose curable resin compositions containing a curable resin and a compound having a specific structure as a curing agent. ing. However, such a curable resin composition has a problem that it is difficult to achieve both flexibility before curing and dielectric properties after curing.

JP-A-2017-186551 International Publication No. WO 2016/114286

An object of the present invention is to provide a benzoxazine compound which can be used for a curable resin composition having excellent flexibility before curing and having excellent dielectric properties after curing. The present invention also provides a curable resin composition containing the benzoxazine compound, an adhesive, an adhesive film, a cured product, a circuit board, an interlayer insulating material, and a multilayer printed wiring board using the curable resin composition. The purpose is to provide.

The present invention is a benzoxazine compound having a diamine residue having an aliphatic skeleton having 4 or more carbon atoms and / or a triamine residue having an aliphatic skeleton having 4 or more carbon atoms and a benzoxazine ring in a molecule. .
Hereinafter, the present invention will be described in detail.

The present inventors have found that by using a benzoxazine compound having a specific structure, a curable resin composition having excellent flexibility before curing and having excellent dielectric properties after curing can be obtained. Was completed.

The benzoxazine compound of the present invention has a diamine residue having an aliphatic skeleton having 4 or more carbon atoms (hereinafter, also simply referred to as “diamine residue”) and / or an aliphatic skeleton having 4 or more carbon atoms in a molecule. A triamine residue (hereinafter, also simply referred to as “triamine residue”). Since the benzoxazine compound of the present invention has the above-mentioned diamine residue and / or the above-mentioned triamine residue, it improves the flexibility of the curable resin composition before curing when it is blended with the curable resin composition. Can be. Further, when the benzoxazine compound of the present invention has the diamine residue and / or the triamine residue and has a benzoxazine ring, the resulting cured product of the curable resin composition has a low dielectric constant and low dielectric constant. It has excellent dielectric properties such as dielectric loss tangent.
In the present specification, the “residue” means a structure of a portion other than a functional group provided for bonding, for example, “diamine residue” means a structure of a portion other than an amino group in a raw material diamine. I do.

The lower limit of the number of carbon atoms in the aliphatic skeleton of the diamine residue and the triamine residue is 4. When the carbon number of the aliphatic skeleton of the diamine residue and the triamine residue is 4 or more, the resulting curable resin composition has excellent flexibility before curing and excellent dielectric properties after curing. It will be. A preferred lower limit of the number of carbon atoms in the aliphatic skeleton of the diamine residue and the triamine residue is 7, and a more preferred lower limit is 8.
The upper limit of the number of carbon atoms in the aliphatic skeleton of the diamine residue and the triamine residue is not particularly limited, but is substantially 90.

The aliphatic skeleton of the diamine residue and the triamine residue may be substituted.
When the aliphatic skeleton of the diamine residue and the triamine residue is substituted, examples of the substituent include a halogen atom, an aryl group, an alkoxy group, a nitro group, and a cyano group.

As the diamine from which the diamine residue is derived, an aliphatic diamine can be used.
Examples of the aliphatic diamine include an aliphatic diamine derived from dimer acid, a linear or branched aliphatic diamine, an aliphatic ether diamine, and an alicyclic diamine. Of these, aliphatic diamines derived from dimer acid are preferred.
Examples of the aliphatic diamine derived from the dimer acid include dimer acid which is a dimer of an aliphatic acid having 10 to 30 carbon atoms such as oleic acid, linoleic acid, linolenic acid, palmitoleic acid, and elaidic acid. Examples include dimer diamines derived therefrom and hydrogenated dimer diamines thereof.
Examples of the linear or branched aliphatic diamine include 1,4-butanediamine, 1,6-hexanediamine, 1,8-octanediamine, 1,9-nonanediamine, 1,10-decanediamine, 11-undecanediamine, 1,12-dodecanediamine, 1,14-tetradecanediamine, 1,16-hexadecanediamine, 1,18-octadecanediamine, 1,20-eicosanediamine, 2-methyl-1,8-octane Examples thereof include diamine, 2-methyl-1,9-nonanediamine, and 2,7-dimethyl-1,8-octanediamine.
Examples of the aliphatic ether diamine include 2,2′-oxybis (ethylamine), 3,3′-oxybis (propylamine), and 1,2-bis (2-aminoethoxy) ethane.
Examples of the alicyclic diamine include 1,3-bis (aminomethyl) cyclohexane, 1,4-bis (aminomethyl) cyclohexane, cyclohexanediamine, methylcyclohexanediamine, and isophoronediamine.

Further, as the diamine from which the diamine residue is derived, the main chain obtained by the reaction of the aliphatic diamine and the acid dianhydride has an acid dianhydride residue, and both ends have an aliphatic diamine. A diamine having an amino group derived therefrom can also be used.

Examples of the acid dianhydride include pyromellitic anhydride, 3,3′-oxydiphthalic anhydride, 3,4′-oxydiphthalic anhydride, 4,4′-oxydiphthalic anhydride, and 4,4 ′ -(4,4'-isopropylidenediphenoxy) diphthalic anhydride, acid dianhydride of 4,4'-bis (2,3-dicarboxylphenoxy) diphenyl ether, p-phenylenebis (trimellitic acid monoester acid) Anhydride), 2,3,3 ', 4'-biphenyltetracarboxylic anhydride, and the like. Among them, 4,4 '-(4,4'-isopropylidenediphenoxy) diphthalic anhydride is preferred.

As the triamine from which the triamine residue is derived, an aliphatic triamine can be used.
Examples of the aliphatic triamine include an aliphatic triamine derived from trimer acid, and a linear or branched aliphatic triamine. Of these, aliphatic triamines derived from the above trimer acids are preferred.
Examples of the aliphatic triamine derived from the trimer acid include trimer acid, which is a trimer of an aliphatic acid having 10 to 30 carbon atoms such as oleic acid, linoleic acid, linolenic acid, palmitoleic acid, and elaidic acid. Examples include a derived trimer triamine and its hydrogenated trimer triamine.
Examples of the linear or branched aliphatic triamine include 3,3′-diamino-N-methyldipropylamine, 3,3′-diaminodipropylamine, diethylenetriamine, bis (hexamethylene) triamine, 2,2 '-Bis (methylamino) -N-methyldiethylamine and the like.
The aliphatic triamine may be used in a state of a mixture with the aliphatic diamine.

Commercially available aliphatic diamines and / or aliphatic triamines include, for example, aliphatic diamines and / or aliphatic triamines manufactured by BASF, and aliphatic diamines and / or aliphatics manufactured by Crowda. Triamine and the like.
Examples of the aliphatic diamine and / or aliphatic triamine manufactured by BASF include Versamine 551 and Versamine 552.
Examples of the aliphatic diamine and / or aliphatic triamine manufactured by Croda include priamine 1071, priamine 1073, priamine 1074, priamine 1075, and the like.

The benzoxazine compound of the present invention has the following formula (1-1) or (1-2) or the following formula (2-) as a structure containing the diamine residue and / or the triamine residue and the benzoxazine ring. It preferably has a structure represented by 1) or (2-2), or the following formula (3). The benzoxazine of the present invention has a structure represented by the following formula (1-1) or (1-2), the following formula (2-1) or (2-2), or the following formula (3): The compounds have better flexibility before curing and dielectric properties after curing.

In the formula (1-1), A is the above-mentioned diamine residue, and X and X 'are each independently a hydrogen atom or any substituent.
In the formula (1-2), A is the above triamine residue, and X, X ′ and X ″ are each independently a hydrogen atom or any substituent.

In the formula (2-1), A is the diamine residue, B and B ′ are each independently any organic group, and R and R ′ are each independently a hydrogen atom or Any substituent, B and each R may combine to form a ring structure, B 'and each R' may combine to form a ring structure, And Y ′ are each independently a hydrogen atom or any substituent.
In the formula (2-2), A is the above triamine residue, B, B ′ and B ″ are each independently any organic group, and R, R ′ and R '' Is each independently a hydrogen atom or an optional substituent, B and each R may be bonded to form a ring structure, and B ′ and each R ′ are To form a ring structure, B '' and each R '' may be combined to form a ring structure, and Y, Y ′ and Y ″ are each independently And is a hydrogen atom or any substituent.

In the formula (3), A and A ′ are each independently the above-mentioned diamine residue, B is any organic group, and R and R ′ are each independently a hydrogen atom or any A substituent, B and R may be bonded to each other to form a ring structure, B and R ′ may be bonded to each other to form a ring structure, and X and X ′ are Each is independently a hydrogen atom or any substituent.

When X and X ′ in the above formula (1-1) and X, X ′ and X ″ in the above formula (1-2) are substituents, examples of the substituent include: Examples thereof include a halogen atom, a linear or branched alkyl group, a linear or branched alkenyl group, an alicyclic group, an aryl group, an alkoxy group, a nitro group, and a cyano group.
When X and X ′ in the above formula (1-1) and X, X ′ and X ″ in the above formula (1-2) are substituents, the hydrogen atom of the aromatic ring is May be substituted with a plurality of the substituents.

When Y and Y ′ in the above formula (2-1) and Y, Y ′ and Y ″ in the above formula (2-2) are substituents, examples of the substituent include: Examples thereof include a linear or branched alkyl group, a linear or branched alkenyl group, an alicyclic group, an aryl group, a phenyl group having an alkyl group or an alkoxy group as a substituent, and the like.
When Y and Y ′ in the above formula (2-1) and Y, Y ′ and Y ″ in the above formula (2-2) are substituents, the hydrogen atom of the aromatic ring is May be substituted with a plurality of the substituents.

B and each R in the above formula (2-1), and B 'and each R', and B and each R, B 'and each R' and B 'in the above formula (2-2) 'And each R''preferably form a ring structure. The ring structure is preferably an imide ring.
In particular, the structure represented by the above formula (2-1) is preferably a structure represented by the following formula (4).

In the formula (4), A is the above diamine residue, C and C ′ are acid dianhydride residues, and Y and Y ′ are each independently a hydrogen atom or any substituent. is there.

When Y and Y ′ in the above formula (4) are substituents, examples of the substituent include a linear or branched alkyl group, a linear or branched alkenyl group, and an alicyclic group. Examples include a phenyl group having a formula group, an aryl group, an alkyl group, or an alkoxy group as a substituent.
When Y and Y ′ in the above formula (4) are substituents, the hydrogen atom of the aromatic ring may be substituted with a plurality of the substituents.

Examples of the acid dianhydrides derived from the acid dianhydride residues represented by C and C ′ in the formula (4) include the acid dianhydrides in the above-described reaction between the aliphatic diamine and the acid dianhydride. Similar ones can be mentioned.

When X and X ′ in the above formula (3) are substituents, examples of the substituent include a halogen atom, a linear or branched alkyl group, and a linear or branched alkenyl group. , An alicyclic group, an aryl group, an alkoxy group, a nitro group, a cyano group and the like.
When X and X ′ in the above formula (3) are substituents, the hydrogen atom of the aromatic ring may be substituted with a plurality of the substituents.

It is preferable that B and R and B and R ′ in the above formula (3) form a ring structure. The ring structure is preferably an imide ring.
In particular, as the structure represented by the above formula (3), a structure represented by the following formula (5) is preferable.

In the formula (5), A and A ′ are each independently the above-described diamine residue, C is an acid dianhydride residue, and X and X ′ are each independently a hydrogen atom or It is an optional substituent.

When X and X ′ in the above formula (5) are substituents, examples of the substituent include a halogen atom, a linear or branched alkyl group, and a linear or branched alkenyl group. , An alicyclic group, an aryl group, an alkoxy group, a nitro group, a cyano group and the like.
When X and X ′ in the above formula (5) are substituents, the hydrogen atom of the aromatic ring may be substituted with a plurality of the substituents.

The benzoxazine compound of the present invention has a repeating structural unit represented by the following formula (6), the following formula (7), or the following formula (8) as a structure containing the diamine residue and the benzoxazine ring. It is also preferred. By having a repeating structural unit represented by the following formula (6), the following formula (7), or the following formula (8), the benzoxazine compound of the present invention has flexibility before curing and after curing. Is excellent due to its dielectric properties and mechanical strength.

In the formula (6), A is the diamine residue described above, and Z is a bond or any organic group. Some or all of the hydrogen atoms of the aromatic ring in the formula (6) may be substituted with any substituent.

In the formula (7), A is the diamine residue, B and B ′ are each independently any organic group, and R and R ′ are each independently a hydrogen atom or any A substituent, B and R may be bonded to each other to form a ring structure, B ′ and R ′ may be bonded to each other to form a ring structure; Organic group.

In the formula (8), A and A ′ are each independently the above-mentioned diamine residue, B is an optional organic group, and R and R ′ are each independently a hydrogen atom or an optional A substituent, B and R may combine to form a ring structure, B and R ′ may combine to form a ring structure, and Z represents a bond or Any organic group. Some or all of the hydrogen atoms of the aromatic ring in the formula (8) may be substituted with an arbitrary substituent.

When the hydrogen atom of the aromatic ring in the above formula (6) is substituted with an arbitrary substituent, examples of the substituent include a halogen atom, a linear or branched alkyl group, a linear or branched alkyl group. Examples include a chain alkenyl group, an alicyclic group, an aryl group, an alkoxy group, a nitro group, and a cyano group.

W in the above formula (7) is preferably the diamine residue or a diamine residue having no aliphatic skeleton having 4 or more carbon atoms.

It is preferable that B and each R and B 'and each R' in the above formula (7) form a ring structure. The ring structure is preferably an imide ring.

When the hydrogen atom of the aromatic ring in the above formula (8) is substituted with an arbitrary substituent, examples of the substituent include a halogen atom, a linear or branched alkyl group, a linear or branched Examples include a chain alkenyl group, an alicyclic group, an aryl group, an alkoxy group, a nitro group, and a cyano group.

It is preferable that B and R, and B and R 'in the above formula (8) form a ring structure. The ring structure is preferably an imide ring.

The preferred lower limit of the molecular weight of the benzoxazine compound of the present invention is 300, and the preferred upper limit is 200,000. When the benzoxazine compound of the present invention is used in the curable resin composition, the obtained curable resin composition has flexibility before curing, and the dielectric properties of the cured product, when the molecular weight is within this range. Will be more excellent. A more preferred lower limit of the molecular weight of the benzoxazine compound of the present invention is 400, and a more preferred upper limit is 100,000.
In the present specification, the above-mentioned `` molecular weight '' is a molecular weight determined from the structural formula for a compound whose molecular structure is specified, but for a compound having a wide distribution of the degree of polymerization and a compound whose modification site is unspecified, It may be expressed using a number average molecular weight. In the present specification, the above “number average molecular weight” is a value determined by gel permeation chromatography (GPC) using tetrahydrofuran as a solvent and measuring in terms of polystyrene. Examples of a column used for measuring the number average molecular weight in terms of polystyrene by GPC include JAIGEL-2HA (manufactured by Nippon Kagaku Kogyo Co., Ltd.).

Among the benzoxazine compounds of the present invention, a method for producing a benzoxazine compound having a structure represented by the above formula (1-1) or the above formula (1-2) includes, for example, the above diamine or the above triamine, Examples thereof include a method of reacting a monofunctional phenol compound with paraformaldehyde.

Examples of the monofunctional phenol compound include phenol, o-cresol, m-cresol, p-cresol, 2,3-dimethylphenol, 2,4-dimethylphenol, 2,5-dimethylphenol, and 2,6-dimethylphenol Phenol, 2-ethylphenol, 3-ethylphenol, 4-ethylphenol, 4-tert-butylphenol, p-octylphenol, p-cumylphenol, dodecylphenol, o-phenylphenol, p-phenylphenol, 1-naphthol, Examples thereof include 2-naphthol, m-methoxyphenol, p-methoxyphenol, m-ethoxyphenol, p-ethoxyphenol, 3,4-dimethylphenol, and 3,5-dimethylphenol. Of these, phenol is preferred.
These monofunctional phenol compounds may be used alone or in combination of two or more.

Among the benzoxazine compounds of the present invention, examples of a method for producing a benzoxazine compound having a structure represented by the above formula (2-1) or the above formula (2-2) include the following methods. .
That is, first, the diamine or the triamine is reacted with a twice molar amount of the acid dianhydride to obtain an imide oligomer having an acid anhydride group at all terminals. By reacting the obtained imide oligomer having an acid anhydride group at all terminals with a 2-fold molar amount of 3-aminophenol, an imide oligomer having a phenolic hydroxyl group at all terminals is obtained. A method of reacting the obtained imide oligomer having a phenolic hydroxyl group at all terminals, a monoamine compound, and paraformaldehyde, and the like can be given.

Examples of the monoamine compound include aniline, o-toluidine, m-toluidine, p-toluidine, 2,3-dimethylaniline, 2,4-dimethylaniline, 2,5-dimethylaniline, 3,4-dimethylaniline, 3,5-dimethylaniline, 2-tert-butylaniline, 3-tert-butylaniline, 4-tert-butylaniline, 1-naphthylamine, 2-naphthylamine, 1-aminoanthracene, 2-aminoanthracene, 9-aminoanthracene , 1-aminopyrene, 3-chloroaniline, o-anisidine, m-anisidine, p-anisidine, 1-amino-2-methylnaphthalene, 4-ethylaniline, 4-ethynylaniline, 4-isopropylaniline, 4- (methylthio ) Aniline and the like. Of these, aniline is preferred.

Among the benzoxazine compounds of the present invention, examples of a method for producing a benzoxazine compound having a structure represented by the above formula (3) include the following methods.
That is, first, an acid dianhydride is reacted with twice the amount of the diamine to obtain an imide oligomer having amino groups at both ends. Next, a method of reacting the obtained imide oligomer having an amino group at both terminals, a monofunctional phenol compound, and paraformaldehyde, and the like are exemplified.

Among the benzoxazine compounds of the present invention, a method for producing a benzoxazine compound having a structure represented by the above formula (6) includes, for example, a method of reacting the above diamine, a bifunctional phenol compound, and paraformaldehyde. And the like.

Examples of the bifunctional phenol compound include 2,2-bis (4-hydroxy-3,5-dimethylphenyl) propane, 2,2-bis (4-hydroxy-3-methylphenyl) propane, 2,2- Bis (4-hydroxyphenyl) butane, 1,1-bis (4-hydroxyphenyl) cyclohexane, 2,2-bis (4-hydroxyphenyl) hexafluoropropane, 2,2-bis (4-hydroxyphenyl) hexafluoro Propane, 4,4′-dihydroxydiphenyl sulfone, 2-hydroxyphenyl ether, 1,1-bis (4-hydroxyphenyl) ethane, 1,1-bis (4-hydroxyphenyl) -1-phenylethane, 1,3 -Bis (2- (4-hydroxyphenyl) -2) propyl) benzene, 1,4-bis (2- (4 Hydroxyphenyl) -2) propyl) benzene.

In the method for producing a benzoxazine compound having a structure represented by the formula (6), a monofunctional phenol compound may be used together with the bifunctional phenol compound.
As the monofunctional phenol compound, those similar to the method for producing a benzoxazine compound having a structure represented by the above formula (1-1) or the above formula (1-2) can be used.

Among the benzoxazine compounds of the present invention, examples of a method for producing a benzoxazine compound having a structure represented by the above formula (7) include the following methods.
That is, first, the above diamine is reacted with twice the amount of an acid dianhydride to obtain an imide oligomer having an acid anhydride group at both terminals. The resulting imide oligomer having an acid anhydride group at both ends is reacted with a 2-fold molar amount of 3-aminophenol to obtain an imide oligomer having a phenolic hydroxyl group at both ends. The obtained imide oligomer having a phenolic hydroxyl group at both ends, the above diamine (diamine having an aliphatic skeleton having 4 or more carbon atoms) or diamine having no aliphatic skeleton having 4 or more carbon atoms, and paraformaldehyde A reaction method and the like can be mentioned.

Examples of the diamine having no aliphatic skeleton having 4 or more carbon atoms include, for example, 3,3′-diaminodiphenylmethane, 3,4′-diaminodiphenylmethane, 4,4′-diaminodiphenylmethane, 3,3′-diaminodiphenylether, 3,4'-diaminodiphenyl ether, 4,4'-diaminodiphenyl ether, o-phenylenediamine, m-phenylenediamine, p-phenylenediamine, 3,3'-diaminodiphenylsulfone, 4,4'-diaminodiphenylsulfone, 1,3-bis (3-aminophenoxy) benzene, 1,3-bis (4-aminophenoxy) benzene, 1,4-bis (4-aminophenoxy) benzene, bis (4- (4-aminophenoxy) phenyl) Methane, 2,2-bis (4- (4-aminophenoxy) Enyl) propane, 1,3-bis (2- (4-aminophenyl) -2-propyl) benzene, 1,4-bis (2- (4-aminophenyl) -2-propyl) benzene, 3,3 ′ -Diamino-4,4'-dihydroxyphenylmethane, 4,4'-diamino-3,3'-dihydroxyphenylmethane, 3,3'-diamino-4,4'-dihydroxyphenyl ether, bisaminophenylfluorene, bis Toluidine fluorene, 4,4'-bis (4-aminophenoxy) biphenyl, 4,4'-diamino-3,3'-dihydroxyphenyl ether, 3,3'-diamino-4,4'-dihydroxybiphenyl, 4, 4'-diamino-2,2'-dihydroxybiphenyl and the like.

Among the benzoxazine compounds of the present invention, examples of a method for producing a benzoxazine compound having a structure represented by the above formula (8) include the following methods.
That is, first, an acid dianhydride is reacted with twice the amount of the diamine to obtain an imide oligomer having amino groups at both ends. Next, a method of reacting the obtained imide oligomer having an amino group at both terminals, a bifunctional phenol compound, and paraformaldehyde, and the like can be mentioned.
As the bifunctional phenol compound, those similar to the method for producing a benzoxazine compound having a structure represented by the above formula (6) can be used.

In the method for producing a benzoxazine compound having a structure represented by the formula (8), a monofunctional phenol compound may be used together with the bifunctional phenol compound.
As the monofunctional phenol compound, those similar to the method for producing a benzoxazine compound having a structure represented by the above formula (1-1) or the above formula (1-2) can be used.

The reaction for forming the benzoxazine ring of the benzoxazine compound of the present invention can be performed in a solvent or without a solvent. When the reaction is performed in a solvent, examples of the reaction solvent to be used include aromatic nonpolar solvents and halogen solvents.
Examples of the aromatic nonpolar solvent include benzene, toluene, xylene, pseudocumene, and mesitylene.
Examples of the halogen solvent include chloroform, dichloromethane and the like.
Among them, toluene and xylene are preferred, and toluene is more preferred, because the burden on the environment and the human body is small, and the versatility is high and the cost is low.
The above solvents may be used alone or in combination of two or more.

When the aromatic non-polar solvent is used as the reaction solvent, alcohols may be used in combination with the aromatic non-polar solvent.
The alcohol is not particularly limited, but is preferably an alcohol having a boiling point lower than that of the aromatic non-polar solvent.
Examples of such alcohols include alcohols having 4 or less carbon atoms. Among them, methanol, ethanol, 1-propanol, isopropanol, 1-butanol, 2-butanol and isobutanol are preferred.
These alcohols may be used alone or in combination of two or more.

During the reaction, the reaction solvent may be refluxed. In the reaction for producing a benzoxazine compound, water is generated in the reaction system. Like the alcohols, the water has an action of suppressing the progress of the synthesis reaction of the benzoxazine compound by solvation. When a solvent that azeotropes with water is used as a synthesis solvent, water generated during the reaction may be azeotropically distilled out of the system in order to allow the reaction to proceed efficiently. In this case, water generated during the reaction can be distilled off by using, for example, a constant-pressure dropping funnel with a cock, a Dimroth condenser, a Dean-Stark apparatus, or the like.

In the reaction for forming the benzoxazine ring of the benzoxazine compound of the present invention, a heating treatment is performed during the synthesis. Examples of the heating treatment method include a method in which the temperature is raised to a predetermined temperature using a temperature controller such as an oil bath, and then the temperature is kept constant.
The predetermined temperature in the heating treatment is not particularly limited, but is preferably adjusted so that the temperature of the reaction solution is 50 ° C. to 150 ° C. When the temperature of the reaction solution is 50 ° C. or higher, the synthesis reaction of the benzoxazine compound can be prevented from slowing down, and the synthesis efficiency can be improved. When the temperature of the reaction solution is 150 ° C. or lower, gelation of the reaction solution during the synthesis reaction can be suppressed.

The duration of the heating treatment is not particularly limited, but it is preferable to continue the heating for about 1 hour to 10 hours after the start of the heating. When the duration of the heating treatment is 1 hour or more, the synthesis reaction can proceed sufficiently and the synthesis yield can be improved. When the duration of the heating treatment is 10 hours or less, gelation of the reaction solution and insolubilization of the benzoxazine compound as a synthetic product can be suppressed.

After the completion of the heating treatment, the reaction medium may be released from contact with a temperature controller such as an oil bath and allowed to cool, or may be cooled using a refrigerant or the like.
Examples of the method of removing the benzoxazine compound from the reaction solution after cooling include poor solvent reprecipitation, concentration and solidification (solvent evaporation under reduced pressure), and spray drying.

The curable resin composition containing the benzoxazine compound of the present invention is also one of the present invention.
By containing the benzoxazine compound of the present invention, the curable resin composition of the present invention has excellent flexibility before curing and has excellent dielectric properties after curing.
The curable resin composition of the present invention is preferably a curable resin composition containing a curable resin, a curing agent, and the benzoxazine compound of the present invention.

The preferable lower limit of the content of the benzoxazine compound of the present invention is 100 parts by weight, and the preferable upper limit thereof is 80 parts by weight, based on 100 parts by weight of the total of the curable resin, the curing agent, and the benzoxazine compound of the present invention. When the content of the benzoxazine compound of the present invention is within this range, the obtained curable resin composition becomes more excellent in flexibility before curing and in dielectric properties after curing. A more preferred lower limit of the content of the benzoxazine compound of the present invention is 10 parts by weight, and a more preferred upper limit is 60 parts by weight.

The curable resin composition of the present invention may contain other benzoxazine compounds other than the benzoxazine compound of the present invention in addition to the benzoxazine compound of the present invention as long as the object of the present invention is not impaired.

Examples of the curable resin include an epoxy resin, a cyanate resin, a phenol resin, an imide resin, a maleimide resin, a silicone resin, an acrylic resin, and a fluororesin. In particular, the curable resin preferably contains at least one selected from the group consisting of an epoxy resin, a cyanate resin, a phenol resin, an imide resin, and a maleimide resin, and more preferably contains an epoxy resin. The curable resin may be used alone or in combination of two or more.

Examples of the epoxy resin include bisphenol A epoxy resin, bisphenol F epoxy resin, bisphenol E epoxy resin, bisphenol S epoxy resin, 2,2′-diallylbisphenol A epoxy resin, hydrogenated bisphenol epoxy resin , Propylene oxide-added bisphenol A epoxy resin, resorcinol epoxy resin, biphenyl epoxy resin, sulfide epoxy resin, diphenyl ether epoxy resin, dicyclopentadiene epoxy resin, naphthalene epoxy resin, fluorene epoxy resin, naphthylene ether Epoxy resin, phenol novolak epoxy resin, ortho-cresol novolak epoxy resin, dicyclopentadiene novolak epoxy resin, biff Nirunoborakku type epoxy resins, naphthalene phenol novolac-type epoxy resin, glycidyl amine type epoxy resin, alkyl polyol type epoxy resin, rubber-modified epoxy resins, glycidyl ester compounds.

Examples of the curing agent include a phenol-based curing agent, a thiol-based curing agent, an amine-based curing agent, an acid anhydride-based curing agent, a cyanate-based curing agent, and an active ester-based curing agent. Among them, phenol-based curing agents and active ester-based curing agents are preferred.

A preferred lower limit of the content of the curing agent in 100 parts by weight of the total of the curable resin, the curing agent, and the benzoxazine compound of the present invention is 5 parts by weight, and a preferred upper limit is 80 parts by weight. When the content of the curing agent is within this range, the curable resin composition obtained will have better curability and storage stability. A more preferred lower limit of the content of the curing agent is 10 parts by weight, and a more preferred upper limit is 60 parts by weight.

The curable resin composition of the present invention preferably contains a curing accelerator. By containing the curing accelerator, the curing time can be shortened and the productivity can be improved.

Examples of the curing accelerator include an imidazole-based curing accelerator, a tertiary amine-based curing accelerator, a phosphine-based curing accelerator, a photobase generator, and a sulfonium salt-based curing accelerator. Among them, imidazole-based curing accelerators are preferred from the viewpoint of curability and storage stability.
The curing accelerators may be used alone or in combination of two or more.

A preferable lower limit of the content of the curing accelerator to 100 parts by weight of the total of the curable resin, the curing agent, and the benzoxazine compound of the present invention is 0.8 parts by weight. When the content of the curing accelerator is 0.8 parts by weight or more, the effect of shortening the curing time is more excellent. A more preferable lower limit of the content of the curing accelerator is 1 part by weight.
Further, from the viewpoint of adhesiveness and the like, a preferable upper limit of the content of the curing accelerator is 10 parts by weight, and a more preferable upper limit is 5 parts by weight.

The curable resin composition of the present invention preferably contains an inorganic filler.
By containing the inorganic filler, the curable resin composition of the present invention becomes more excellent in moisture absorption reflow resistance and plating resistance while maintaining excellent adhesiveness and the like.

The inorganic filler is preferably at least one of silica and barium sulfate. By containing at least one of silica and barium sulfate as the inorganic filler, the curable resin composition of the present invention becomes more excellent in moisture absorption reflow resistance and plating resistance.

Examples of the inorganic filler other than the silica and the barium sulfate include alumina, aluminum nitride, boron nitride, silicon nitride, glass powder, glass frit, glass fiber, carbon fiber, and inorganic ion exchanger.

The inorganic fillers may be used alone or in combination of two or more.

The preferable lower limit of the average particle diameter of the inorganic filler is 50 nm, and the preferable upper limit is 4 μm. When the average particle diameter of the inorganic filler is within this range, the curable resin composition obtained has better coatability. A more preferred lower limit of the average particle size of the inorganic filler is 100 nm, and a more preferred upper limit is 3 μm.

A preferable lower limit of the content of the inorganic filler to 100 parts by weight of the total of the curable resin, the curing agent, and the benzoxazine compound of the present invention is 50 parts by weight, and a preferable upper limit is 500 parts by weight. When the content of the inorganic filler is within this range, the obtained curable resin composition becomes more excellent in moisture absorption reflow resistance and plating resistance. A more preferred lower limit of the content of the inorganic filler is 100 parts by weight.

The curable resin composition of the present invention may contain a flow modifier for the purpose of improving the wettability to an adherend in a short time and the shape retention.
Examples of the flow regulator include fumed silica such as Aerosil and layered silicate.
The flow regulator may be used alone or in combination of two or more.
Further, as the above-mentioned flow regulator, those having an average particle diameter of less than 100 nm are suitably used.

A preferred lower limit of the content of the flow modifier to 100 parts by weight of the total of the curable resin, the curing agent, and the benzoxazine compound of the present invention is 0.1 part by weight, and a preferred upper limit is 50 parts by weight. When the content of the flow control agent is in this range, effects such as improvement in wettability to an adherend in a short time and shape retention are improved. A more preferred lower limit of the content of the flow regulator is 0.5 part by weight, and a more preferred upper limit is 30 parts by weight.

The curable resin composition of the present invention may contain an organic filler for the purpose of stress relaxation, imparting toughness, and the like.
Examples of the organic filler include silicone rubber particles, acrylic rubber particles, urethane rubber particles, polyamide particles, polyamideimide particles, polyimide particles, benzoguanamine particles, and core-shell particles thereof. Among them, polyamide particles, polyamideimide particles and polyimide particles are preferred.
The organic filler may be used alone or in combination of two or more.

The preferable upper limit of the content of the organic filler to 100 parts by weight of the total of the curable resin, the curing agent, and the benzoxazine compound of the present invention is 300 parts by weight. When the content of the organic filler is 300 parts by weight or less, the obtained cured product of the curable resin composition becomes more excellent in toughness and the like while maintaining excellent adhesiveness and the like. A more preferred upper limit of the content of the organic filler is 200 parts by weight.

The curable resin composition of the present invention may contain a flame retardant.
Examples of the flame retardant include metal hydrates such as boehmite-type aluminum hydroxide, aluminum hydroxide, and magnesium hydroxide, halogen compounds, phosphorus compounds, and nitrogen compounds. Above all, boehmite-type aluminum hydroxide is preferred.
The flame retardants may be used alone or in combination of two or more.

The preferred lower limit of the content of the flame retardant to 100 parts by weight of the total of the curable resin, the curing agent and the benzoxazine compound of the present invention is 5 parts by weight, and the preferred upper limit is 200 parts by weight. When the content of the flame retardant is within this range, the resulting curable resin composition has excellent flame retardancy while maintaining excellent adhesiveness and the like. A more preferred lower limit of the content of the flame retardant is 10 parts by weight, and a more preferred upper limit is 150 parts by weight.

The curable resin composition of the present invention may contain a thermoplastic resin as long as the object of the present invention is not impaired. By using the above-mentioned thermoplastic resin, the curable resin composition of the present invention is more excellent in flow characteristics, it is easier to achieve both the filling property and the leaching prevention property at the time of thermocompression bonding, and the bending resistance after curing. It becomes more excellent by the property.

Examples of the thermoplastic resin include a polyimide resin, a phenoxy resin, a polyamide resin, a polyamideimide resin, and a polyvinyl acetal resin. Among them, phenoxy resins are preferred from the viewpoint of heat resistance and handleability.
The thermoplastic resins may be used alone or in combination of two or more.

A preferred lower limit of the number average molecular weight of the thermoplastic resin is 3,000, and a preferred upper limit is 100,000. When the number average molecular weight of the thermoplastic resin is in this range, the resulting curable resin composition has more excellent flow characteristics and flex resistance after curing. A more preferred lower limit of the number average molecular weight of the thermoplastic resin is 5,000, and a more preferred upper limit is 50,000.

The preferable lower limit of the content of the thermoplastic resin to 100 parts by weight of the total of the above-mentioned curable resin, the above-mentioned curing agent and the benzoxazine compound of the present invention is 2 parts by weight, and the preferable upper limit thereof is 60 parts by weight. When the content of the thermoplastic resin is 2 parts by weight or more, the obtained curable resin composition becomes more excellent in flow characteristics and bending resistance after curing. When the content of the thermoplastic resin is 60 parts by weight or less, the obtained curable resin composition becomes more excellent in adhesiveness and heat resistance. A more preferred lower limit of the content of the thermoplastic resin is 3 parts by weight, and a more preferred upper limit is 50 parts by weight.

The curable resin composition of the present invention may contain a solvent from the viewpoint of coatability and the like.
As the solvent, a non-polar solvent having a boiling point of 160 ° C. or less or an aprotic polar solvent having a boiling point of 160 ° C. or less is preferable from the viewpoint of coating properties and storage stability.
Examples of the non-polar solvent having a boiling point of 160 ° C. or less or an aprotic polar solvent having a boiling point of 160 ° C. or less include, for example, ketone solvents, ester solvents, hydrocarbon solvents, halogen solvents, ether solvents, and nitrogen-containing solvents. System solvents and the like.
Examples of the ketone-based solvent include acetone, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone, and the like.
Examples of the ester solvent include methyl acetate, ethyl acetate, isobutyl acetate and the like.
Examples of the hydrocarbon solvent include benzene, toluene, normal hexane, isohexane, cyclohexane, methylcyclohexane, normal heptane and the like.
Examples of the halogen-based solvent include dichloromethane, chloroform, trichloroethylene and the like.
Examples of the ether solvent include diethyl ether, tetrahydrofuran, 1,4-dioxane, 1,3-dioxolan, and the like.
Examples of the nitrogen-containing solvent include acetonitrile and the like.
Among them, from the viewpoints of handleability and solubility of the above-mentioned curing agent, a ketone-based solvent having a boiling point of 60 ° C or higher, an ester-based solvent having a boiling point of 60 ° C or higher, and an ether-based solvent having a boiling point of 60 ° C or higher are used. At least one selected from the group is preferred. Examples of such a solvent include methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone, ethyl acetate, isobutyl acetate, 1,4-dioxane, 1,3-dioxolan, tetrahydrofuran and the like.
The above “boiling point” means a value measured under a condition of 101 kPa or a value converted to 101 kPa in a boiling point conversion chart or the like.

A preferred lower limit of the content of the solvent in the curable resin composition of the present invention is 15% by weight, and a preferred upper limit is 80% by weight. When the content of the solvent is in this range, the curable resin composition of the present invention is more excellent in coatability and the like. The more preferable lower limit of the content of the solvent is 20% by weight, and the more preferable upper limit is 70% by weight.

The curable resin composition of the present invention may contain a reactive diluent as long as the object of the present invention is not impaired.
As the reactive diluent, a reactive diluent having two or more reactive functional groups in one molecule is preferable from the viewpoint of adhesion reliability.

The curable resin composition of the present invention may further contain additives such as a coupling agent, a dispersant, a storage stabilizer, an anti-bleeding agent, a fluxing agent, and a leveling agent.

As a method for producing the curable resin composition of the present invention, for example, using a homodisper, a universal mixer, a Banbury mixer, a mixer such as a kneader, a curable resin, a curing agent, and the benzoxazine compound of the present invention And a solvent or the like added as necessary.

The curable resin composition of the present invention can be obtained by applying the curable resin composition of the present invention on a base film and drying the curable resin composition. The cured product can be obtained by curing the product film.
A cured product obtained by curing the curable resin composition of the present invention is also one of the present invention.

In the curable resin composition of the present invention, the preferable upper limit of the dielectric loss tangent at 23 ° C. of the cured product is 0.0045. When the dielectric loss tangent at 23 ° C. of the cured product falls within this range, the curable resin composition of the present invention can be suitably used for an interlayer insulating material such as a multilayer printed wiring board. A more preferred upper limit of the dielectric loss tangent of the cured product at 23 ° C. is 0.0040, and a still more preferred upper limit is 0.0035.
The “dielectric tangent” is a value measured under a condition of 1.0 GHz using a dielectric constant measuring device and a network analyzer. The cured product for measuring the “dielectric tangent” can be obtained by heating the curable resin composition film having a thickness of 40 to 200 μm at 190 ° C. for 90 minutes.

The curable resin composition of the present invention can be used for a wide range of applications. For example, adhesives for printed wiring boards, adhesives for coverlays of flexible printed circuit boards, copper-clad laminates, adhesives for semiconductor bonding, interlayer insulating materials, prepregs, sealing agents for LEDs, adhesives for structural materials, etc. Can be used.
Among them, it is suitably used for adhesives. An adhesive containing the curable resin composition of the present invention is also one of the present invention.

The curable resin film can be suitably used as an adhesive film. An adhesive film using the curable resin composition of the present invention is also one of the present invention.
Further, a circuit board having the cured product of the present invention is also one of the present invention.

The curable resin composition of the present invention can be suitably used as an interlayer insulating material such as a multilayer printed wiring board because the cured product has a low dielectric constant, a low dielectric loss tangent, and excellent dielectric properties. An interlayer insulating material using the curable resin composition of the present invention is also one of the present invention.
Further, it has a circuit board, a plurality of insulating layers disposed on the circuit board, and a metal layer disposed between the plurality of insulating layers, wherein the insulating layer is a cured product of the interlayer insulating material of the present invention. Is also one of the present invention.

According to the present invention, it is possible to provide a benzoxazine compound that can be used for a curable resin composition having excellent flexibility before curing and having excellent dielectric properties after curing. Further, according to the present invention, a curable resin composition containing the benzoxazine compound, an adhesive using the curable resin composition, an adhesive film, a cured product, a circuit board, an interlayer insulating material, and a multilayer print A wiring board can be provided.

Hereinafter, the present invention will be described in more detail with reference to Examples, but the present invention is not limited to these Examples.

(Synthesis Example 1 (Preparation of Benzoxazine Compound A))
In a 500 mL flask equipped with a reflux tube, a constant pressure dropping funnel equipped with a cock, and a Dimroth condenser, 150 mL of toluene and 50 mL of methanol were added at once at 25 ° C as a mixed solvent and mixed. Next, 18.8 g (0.2 mol) of phenol (manufactured by Tokyo Chemical Industry Co., Ltd.) and 56.2 g (0.1 mol) of preamine 1074 (manufactured by Croda), which is a hydrogenated dimer diamine, were placed in a flask at 25 ° C. Was added all at once and mixed. Thereafter, 13.2 g (0.44 mol) of paraformaldehyde (manufactured by Tokyo Kasei Kogyo Co., Ltd.) was added all at once to the flask at 25 ° C. and mixed to obtain a mixed solution.
The flask containing the obtained mixed solution was immersed in an oil bath whose temperature was set to 120 ° C., and the reaction was allowed to proceed by heating while refluxing. One hour after the start of reflux, water produced in the reaction system was distilled off from the system by azeotropic distillation with toluene and methanol.
After the reaction was allowed to proceed for 4 hours from the start of the distillation, the flask was taken out of the oil bath, and the obtained reaction solution was cooled to 25 ° C. After cooling, the reaction solution was poured into 1 L of methanol to precipitate a reaction product. The precipitated solid was dried under reduced pressure to obtain benzoxazine compound A.
According to ¹ H-NMR, GPC, and FT-IR analysis, the benzoxazine compound A was a benzoxazine compound having a structure represented by the above formula (1-1) (A is a hydrogenated dimer diamine residue). , X and X ′ contained a hydrogen atom). The benzoxazine compound A had a number average molecular weight of 800.

(Synthesis Example 2 (Preparation of Benzoxazine Compound B))
A benzoxazine compound B was obtained in the same manner as in Synthesis Example 1 except that 56.8 g (0.1 mol) of diamine diamine priamine 1073 (manufactured by Croda) was used instead of priamine 1074.
According to ¹ H-NMR, GPC, and FT-IR analysis, the benzoxazine compound B was a benzoxazine compound having a structure represented by the above formula (1-1) (A is a dimer diamine residue, X and X ′ contained a hydrogen atom). The benzoxazine compound B had a number average molecular weight of 800.

(Synthesis Example 3 (Preparation of Benzoxazine Compound C))
A benzoxazine compound C was prepared in the same manner as in Synthesis Example 1 except that 61.7 g (0.1 mol) of priamine 1071 (manufactured by Croda), which was a mixture of dimer diamine and trimer triamine, was used instead of priamine 1074. I got
According to ¹ H-NMR, GPC, and FT-IR analysis, the benzoxazine compound C was a benzoxazine compound having a structure represented by the above formula (1-1) (A is a dimer diamine residue, X and X ′ contained a hydrogen atom). In addition, the benzoxazine compound C includes a benzoxazine compound having a structure represented by the above formula (1-2) (A is a trimer triamine residue, X, X ′, and X ″ are hydrogen atoms) It was confirmed. The number average molecular weight of the benzoxazine compound C was 850.

(Synthesis Example 4 (Preparation of Benzoxazine Compound D))
56.8 g (0.1 mol) of priamine 1073 (manufactured by Croda) which is a dimer diamine was dissolved in 400 g of N-methylpyrrolidone ("NMP" manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.). 104.1 g (0.2 mol) of 4,4 ′-(4,4′-isopropylidene diphenoxy) diphthalic anhydride (manufactured by Tokyo Chemical Industry Co., Ltd.) as an aromatic tetracarboxylic acid was added to the obtained solution. The mixture was stirred at 25 ° C. for 2 hours to be reacted to obtain an amic acid oligomer solution. After N-methylpyrrolidone was removed from the obtained amic acid oligomer solution under reduced pressure, the solution was heated at 300 ° C. for 2 hours to obtain an imide oligomer having an acid anhydride group at both terminals.
26.8 g (0.2 mol) of 3-aminophenol (manufactured by Tokyo Chemical Industry Co., Ltd.) was dissolved in 400 g of N-methylpyrrolidone (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd., “NMP”). To the resulting solution, 157.3 g (0.1 mol) of an imide oligomer having an acid anhydride group at both terminals was added, and the mixture was stirred at 25 ° C. for 2 hours to be reacted to obtain an amic acid oligomer solution. After removing N-methylpyrrolidone from the obtained amic acid oligomer solution under reduced pressure, the mixture was heated at 300 ° C. for 2 hours to obtain an imide oligomer having phenolic hydroxyl groups at both ends.
In a 500 mL flask equipped with a reflux tube, a constant pressure dropping funnel equipped with a cock, and a Dimroth condenser, 150 mL of toluene and 50 mL of methanol were added at once at 25 ° C as a mixed solvent and mixed. Next, 174.7 g (0.1 mol) of an imide oligomer having phenolic hydroxyl groups at both ends and 18.6 g (0.2 mol) of aniline (manufactured by Tokyo Chemical Industry Co., Ltd.) were placed in a flask at 25 ° C. Added and mixed. Thereafter, 13.2 g (0.44 mol) of paraformaldehyde (manufactured by Tokyo Kasei Kogyo Co., Ltd.) was added all at once to the flask at 25 ° C. and mixed to obtain a mixed solution.
The flask containing the obtained mixed solution was immersed in an oil bath whose temperature was set to 120 ° C., and the reaction was allowed to proceed by heating while refluxing. One hour after the start of reflux, water produced in the reaction system was distilled off from the system by azeotropic distillation with toluene and methanol.
After the reaction was allowed to proceed for 4 hours from the start of distillation, the flask was taken out of the oil bath, and the obtained reaction solution was cooled to 25 ° C. After cooling, the reaction solution was poured into 1 L of methanol to precipitate a reaction product. The precipitated solid was dried under reduced pressure to obtain a benzoxazine compound D.
According to ¹ H-NMR, GPC, and FT-IR analysis, the benzoxazine compound D was a benzoxazine compound having a structure represented by the above formula (4) (A is a dimer diamine residue, C and C ′ Contains 4,4 ′-(4,4′-isopropylidene diphenoxy) diphthalic anhydride residue, and Y and Y ′ are phenyl groups. The number average molecular weight of the benzoxazine compound D was 2,000.

(Synthesis Example 5 (Preparation of Benzoxazine Compound E))
113.6 g (0.2 mol) of priamine 1073 (manufactured by Croda), which is a dimer diamine, was dissolved in 400 g of N-methylpyrrolidone (“NMP” manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.). 52.0 g (0.1 mol) of 4,4 ′-(4,4′-isopropylidene diphenoxy) diphthalic anhydride (manufactured by Tokyo Chemical Industry Co., Ltd.) was added to the resulting solution as an aromatic tetracarboxylic acid. The mixture was stirred at 25 ° C. for 2 hours to be reacted to obtain an amic acid oligomer solution. After N-methylpyrrolidone was removed from the obtained amic acid oligomer solution under reduced pressure, the solution was heated at 300 ° C. for 2 hours to obtain an imide oligomer having amino groups at both ends.
In a 500 mL flask equipped with a reflux tube, a constant pressure dropping funnel equipped with a cock, and a Dimroth condenser, 150 mL of toluene and 50 mL of methanol were added at once at 25 ° C as a mixed solvent and mixed. Next, 18.8 g (0.2 mol) of phenol (manufactured by Tokyo Chemical Industry Co., Ltd.) and 160.7 g (0.1 mol) of the obtained imide oligomer having an amino group at both terminals were placed in a flask at 25 ° C. Was added all at once and mixed. Thereafter, 13.2 g (0.44 mol) of paraformaldehyde (manufactured by Tokyo Kasei Kogyo Co., Ltd.) was added all at once to the flask at 25 ° C. and mixed to obtain a mixed solution.
The flask containing the obtained mixed solution was immersed in an oil bath whose temperature was set to 120 ° C., and the reaction was allowed to proceed by heating while refluxing. One hour after the start of reflux, water produced in the reaction system was distilled off from the system by azeotropic distillation with toluene and methanol.
After the reaction was allowed to proceed for 4 hours from the start of the distillation, the flask was taken out of the oil bath, and the obtained reaction solution was cooled to 25 ° C. After cooling, the reaction solution was poured into 1 L of methanol to precipitate a reaction product. The precipitated solid was dried under reduced pressure to obtain a benzoxazine compound E.
In addition, ¹ H-NMR, GPC, and FT-IR analysis confirmed that the benzoxazine compound E contained a benzoxazine compound having a structure represented by the above formula (5). In the benzoxazine compound E, A and A ′ in the above formula (5) are imide oligomer residues having amino groups at both ends, and C is 4,4 ′-(4,4′-isopropylidene diphenoxy) diphthal The acid anhydride residues, X and X ', were hydrogen atoms. The number average molecular weight of the benzoxazine compound E was 1960.

(Synthesis Example 6 (Preparation of Benzoxazine Compound F))
In a 500 mL flask equipped with a reflux tube, a constant pressure dropping funnel equipped with a cock, and a Dimroth condenser, 150 mL of toluene and 50 mL of methanol were added at once at 25 ° C as a mixed solvent and mixed. Next, 34.7 g (0.1 mol) of 1,3-bis (2- (4-hydroxyphenyl) -2-propyl) benzene (manufactured by Tokyo Chemical Industry Co., Ltd., “bisphenol M”) and hydrogenated dimer diamine were used. 56.2 g (0.1 mol) of a certain preamine 1074 (manufactured by Croda) were added all at once to the flask at 25 ° C. and mixed. Thereafter, 13.2 g (0.44 mol) of paraformaldehyde (manufactured by Tokyo Kasei Kogyo Co., Ltd.) was added all at once to the flask at 25 ° C. and mixed to obtain a mixed solution.
The flask containing the obtained mixed solution was immersed in an oil bath set at a temperature of 80 ° C., and the reaction was allowed to proceed by heating while refluxing. One hour after the start of reflux, water produced in the reaction system was distilled off from the system by azeotropic distillation with toluene and methanol.
After the reaction was allowed to proceed for 4 hours from the start of the distillation, the flask was taken out of the oil bath, and the obtained reaction solution was cooled to 25 ° C. After cooling, the reaction solution was poured into 1 L of methanol to precipitate a reaction product. The precipitated solid was dried under reduced pressure to obtain a benzoxazine compound F.
According to ¹ H-NMR, GPC, and FT-IR analysis, the benzoxazine compound F was a benzoxazine compound having a repeating structural unit represented by the above formula (6) (A is a hydrogenated dimer diamine residue). , And Z contain a group represented by the following formula (9)). The number average molecular weight of the benzoxazine compound F was 12,000.

In the formula (9), * is a bonding position.

(Synthesis Example 7 (Preparation of Benzoxazine Compound G))
Instead of the primamine 1074, 29.2 g of 1,3-bis (3-aminophenoxy) benzene (“APB-N”, manufactured by Mitsui Chemicals, Inc.), which is a diamine having no aliphatic skeleton having 4 or more carbon atoms, is used. Benzoxazine compound G was obtained in the same manner as in Synthesis Example 1 except that 0.1 mol) was used.
According to ¹ H-NMR, GPC and FT-IR analyses, the benzoxazine compound G was found to have a portion corresponding to A in the above formula (1-1) with 1,3-bis (3-aminophenoxy) benzene residue. It was confirmed that a benzoxazine compound which is a group and a portion corresponding to X and X ′ was a hydrogen atom was included. The number average molecular weight of the benzoxazine compound G was 600.

(Examples 1 to 7, Comparative Examples 1 and 2)
Methyl ethyl ketone was added as a solvent to each material having the compounding ratio shown in Table 1 and stirred with a stirrer at 1200 rpm for 4 hours to obtain a curable resin composition. In addition, in the composition of Table 1, the solid content excluding the solvent was described.
Using an applicator, the obtained curable resin composition was applied on a release-treated surface of a PET film (“XG284” manufactured by Toray Industries, Inc., thickness: 25 μm). Thereafter, the film is dried in a gear oven at 100 ° C. for 5 minutes to evaporate the solvent to obtain an uncured laminated film having a PET film and a curable resin composition layer having a thickness of 40 μm on the PET film. Was.

<Evaluation>
The following evaluation was performed about each uncured laminated film obtained by the Example and the comparative example. The results are shown in Table 1.

(Flexibility)
Each of the uncured laminated films obtained in Examples and Comparative Examples was cut out into a rectangle of 10 cm long × 5 cm wide. This film was folded 90 ° or 180 ° so that the PET film layer was on the inside, and then returned to a flat shape, and the state of the film was visually checked. In addition, when bent at 180 degrees, it is easier to break than when bent at 90 degrees.
"○" indicates that there was no crack when bent at 90 or 180 degrees, "△" indicates that there was a crack when bent at 180 degrees, and "△" indicates that there was no crack when bent at 90 degrees. The sample was evaluated as "x" when there was a crack in any of them, and the flexibility was evaluated.

(Dielectric properties)
Each of the uncured laminated films obtained in Examples and Comparative Examples was cut into a size of 2 mm in width and 80 mm in length. The base PET film was peeled off from the curable resin composition layer of the uncured laminated film after cutting, and five layers of the curable resin composition layer were laminated using a laminator to obtain a laminate having a thickness of about 200 μm. The obtained laminate was heated at 190 ° C. for 90 minutes to obtain a cured product. Using the cavity resonance perturbation method dielectric constant measuring device CP521 (manufactured by Kanto Electronics Applied Development Co.) and the network analyzer N5224A PNA (manufactured by Keysight Technology), the obtained cured body was subjected to a cavity resonance method at 23 ° C. The dielectric loss tangent was measured at 1.0 GHz.
When the dielectric loss tangent was 0.0035 or less, “◎”, when the dielectric loss tangent was more than 0.0035 and 0.0040 or less, “○”, when the dielectric loss tangent was more than 0.0040 and 0.0045 or less. The dielectric properties were evaluated as “Δ” when there was, and “x” when the dielectric loss tangent exceeded 0.0045.

(Desmearing property (removability of residue on via bottom))
(1) Laminate and semi-cured CCL substrate (Hitachi Kasei Kogyo Co., Ltd., "E679FG") both sides immersed in copper surface roughening agent (Mec, "Mech etch bond CZ-8100"), copper surface Was roughened. Each of the uncured laminated films obtained in Examples and Comparative Examples was set on both sides of the CCL substrate from the curable resin composition layer side, and a diaphragm type vacuum laminator (“MVLP-500” manufactured by Meiki Seisakusho Co., Ltd.) ) Was used to laminate on both sides of the CCL substrate to obtain an uncured laminated sample A. Lamination was performed by reducing the pressure to 13 hPa or less by reducing the pressure for 20 seconds, and then pressing at 100 ° C. and a pressure of 0.8 MPa for 20 seconds.
After peeling the base PET film from the obtained uncured laminated sample A, the curable resin composition was cured under the curing conditions of 170 ° C. and 30 minutes to obtain a semi-cured laminated sample.

(2) Formation of Via (Through Hole) Using a CO ₂ laser (manufactured by Hitachi Via Mechanics), the obtained semi-cured laminated sample had a diameter of 60 μm at the upper end and 40 μm at the lower end (bottom). By forming a certain via (through hole), a semi-cured product of the curable resin composition is laminated on the CCL substrate, and a via (through hole) is formed in the semi-cured product of the curable resin composition. The obtained laminated body B was obtained.

(3) Removal of Residue at the Bottom of Via (a) Swelling The obtained laminate B was placed in a swelling liquid at 70 ° C. (manufactured by Atotech Japan, “Swelling Dip Securiganto P”) for 10 minutes. Rocked. Thereafter, the substrate was washed with pure water.

(B) Permanganate treatment (roughening treatment and desmear treatment)
The swelled laminate B was placed in a roughened aqueous solution of potassium permanganate (“Concentrate Compact CP” manufactured by Atotech Japan) at 80 ° C. and shaken for 30 minutes. Next, the sample was treated for 2 minutes using a cleaning solution at 25 ° C. (“Reduction Securiganto P” manufactured by Atotech Japan), and then washed with pure water to obtain Evaluation Sample 1.

The bottom of the via of the evaluation sample 1 was observed with a scanning electron microscope (SEM), and the maximum smear length from the wall surface of the via bottom was measured.
"◎" indicates that the maximum smear length was less than 2 μm, "最大" indicates that the maximum smear length was 2 μm or more and less than 2.5 μm, and “○” indicates that the maximum smear length was 2.5 μm or more and less than 3 μm. Δ, the case where the maximum smear length was 3 μm or more was evaluated as “x”, and the desmear property (removability of the residue at the bottom of the via) was evaluated.

(Plating adhesion)
A 70 ° C. swelling solution (aqueous solution prepared from “Swelling Dip Securigant P” manufactured by Atotech Japan and sodium hydroxide (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.)) was added to the above “(desmear property (via bottom (Removability of residue)) The semi-cured laminated sample produced in the same manner as in the above) was put into the container and rocked for 10 minutes. Thereafter, the substrate was washed with pure water.
A semi-cured solution that has been swelled in a roughened aqueous solution of sodium permanganate at 80 ° C (aqueous solution prepared from “Concentrate Compact CP” manufactured by Atotech Japan and sodium hydroxide (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.)). The laminated sample was put and rocked for 30 minutes. Then, after washing for 2 minutes with a washing liquid of 25 ° C. (aqueous solution prepared from Atotech Japan, “Reduction Securiganto P” and sulfuric acid (manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.)), further washing with pure water Thus, a roughened semi-cured product was formed on the CCL substrate.
The surface of the roughened semi-cured product was treated with an alkaline cleaner at 60 ° C. (“Cleaner Securigant 902” manufactured by Atotech Japan) for 5 minutes, and degreased and washed. After washing, the semi-cured product was treated with a pre-dip liquid at 25 ° C. (manufactured by Atotech Japan, “Pre-Dip Neo Gant B”) for 2 minutes. Thereafter, the semi-cured product was treated with an activator solution ("Activator Neo Gant 834", manufactured by Atotech Japan) at 40 ° C for 5 minutes to attach a palladium catalyst.
Next, the semi-cured product is treated with a reducing solution at 30 ° C. (manufactured by Atotech Japan, “Reducer Neogant WA”) for 5 minutes, and then a chemical copper solution (all manufactured by Atotech Japan, “Basic Print Gant MSK-DK”). , "Copper Print Gant MSK", "Stabilizer Print Gant MSK", "Reducer Cu"). Electroless plating was performed until the plating thickness became about 0.5 μm. After the electroless plating, annealing was performed at a temperature of 120 ° C. for 30 minutes to remove the remaining hydrogen gas. All steps up to the step of electroless plating were performed while the semi-cured material was oscillated with a treatment liquid of 2 L on a beaker scale.
Electroplating was performed on the semi-cured material subjected to the electroless plating. Electroplating is performed using copper sulfate solution (copper sulfate pentahydrate (manufactured by Fujifilm Wako Pure Chemical), sulfuric acid (manufactured by Fujifilm Wako Pure Chemical), Atotech Japan, "Basic Leveler Capparaside HL", and Aqueous current of 0.6 A / cm ² was passed using an aqueous solution prepared from “Correcting Agent Capalaside GS” manufactured by Atotech Japan Co., Ltd., and the plating was performed until the plating thickness became about 25 μm. After the electrolytic plating, the semi-cured product was heated at 190 ° C. for 90 minutes to further cure the semi-cured product, thereby obtaining a cured product having a copper plating layer laminated on the upper surface.
In the cured product on which the obtained copper plating layer was laminated, a notch having a width of 10 mm was formed on the surface of the copper plating layer. Thereafter, the adhesion strength between the cured product (insulating layer) and the metal layer (copper plating layer) was measured using a tensile tester (“AG-5000B” manufactured by Shimadzu Corporation) at a crosshead speed of 5 mm / min. 90 ° peel strength).
“◎” indicates that the peel strength was 0.50 kgf / cm or more, “○” indicates that the peel strength was 0.45 kgf / cm or more and less than 0.50 kgf / cm, and 0.40 kgf / cm. The plating adhesion was evaluated as “△” when the value was less than 0.45 kgf / cm and “×” when the peel strength was less than 0.40 kgf / cm.

According to the present invention, it is possible to provide a benzoxazine compound that can be used for a curable resin composition having excellent flexibility before curing and having excellent dielectric properties after curing. Further, according to the present invention, a curable resin composition containing the benzoxazine compound, an adhesive using the curable resin composition, an adhesive film, a cured product, a circuit board, an interlayer insulating material, and a multilayer print A wiring board can be provided.

Claims (13)

1. A benzoxazine compound having a diamine residue having an aliphatic skeleton having 4 or more carbon atoms and / or a triamine residue having an aliphatic skeleton having 4 or more carbon atoms and a benzoxazine ring in a molecule.
2. 2. The benzo according to claim 1, wherein the diamine and / or triamine from which the diamine residue and / or the triamine residue is derived is an aliphatic diamine and / or an aliphatic triamine derived from dimer acid and / or trimer acid. Oxazine compounds.
3. 3. The benzole according to claim 1, which has a structure represented by the following formula (1-1) or (1-2), the following formula (2-1) or (2-2), or the following formula (3). Oxazine compounds.
   

   

   In the formula (1-1), A is the diamine residue, and X and X ′ are each independently a hydrogen atom or any substituent.
   In the formula (1-2), A is the aforementioned triamine residue, and X, X ′ and X ″ are each independently a hydrogen atom or any substituent.
   

   

   In the formula (2-1), A is the diamine residue, B and B ′ are each independently any organic group, and R and R ′ are each independently a hydrogen atom or Any substituent, B and each R may combine to form a ring structure, B 'and each R' may combine to form a ring structure, And Y ′ are each independently a hydrogen atom or any substituent.
   In the formula (2-2), A is the triamine residue, B, B ′ and B ″ are each independently an arbitrary organic group, and R, R ′ and R '' Is each independently a hydrogen atom or an optional substituent, B and each R may be bonded to form a ring structure, and B ′ and each R ′ are And B '' and each R '' may combine to form a ring structure, and Y, Y ′ and Y ″ are each independently And is a hydrogen atom or any substituent.
   

   

   In the formula (3), A and A ′ are each independently the diamine residue, B is an optional organic group, and R and R ′ are each independently a hydrogen atom or an optional A substituent, B and R may be bonded to each other to form a ring structure, B and R ′ may be bonded to each other to form a ring structure, and X and X ′ are Each is independently a hydrogen atom or any substituent.
4. The benzoxazine compound according to claim 1 or 2, which has a repeating structural unit represented by the following formula (6), the following formula (7), or the following formula (8).
   

   

   In the formula (6), A is the diamine residue, and Z is a bond or any organic group. Some or all of the hydrogen atoms of the aromatic ring in the formula (6) may be substituted with any substituent.
   

   

   In the formula (7), A is the diamine residue, B and B ′ are each independently any organic group, and R and R ′ are each independently a hydrogen atom or any A substituent, B and R may be bonded to each other to form a ring structure, B ′ and R ′ may be bonded to each other to form a ring structure; Organic group.
   

   

   In the formula (8), A and A ′ are each independently the diamine residue, B is an optional organic group, and R and R ′ are each independently a hydrogen atom or an optional A substituent, B and R may combine to form a ring structure, B and R ′ may combine to form a ring structure, and Z represents a bond or Any organic group. Some or all of the hydrogen atoms of the aromatic ring in the formula (8) may be substituted with an arbitrary substituent.
5. A curable resin composition containing the benzoxazine compound according to claim 1.
6. The curable resin composition according to claim 5, comprising a curable resin, a curing agent, and the benzoxazine compound according to claim 1.
7. The curable resin composition according to claim 6, wherein the curable resin includes at least one selected from the group consisting of an epoxy resin, a cyanate resin, a phenol resin, an imide resin, and a maleimide resin.
8. An adhesive comprising the curable resin composition according to claim 5, 6, or 7.
9. An adhesive film using the curable resin composition according to claim 5, 6, or 7.
10. A cured product obtained by curing the curable resin composition according to claim 5, 6, or 7.
11. A circuit board having the cured product according to claim 10.
12. An interlayer insulating material comprising the curable resin composition according to claim 5, 6 or 7.
13. 13. A cured product of the interlayer insulating material according to claim 12, comprising: a circuit board; a plurality of insulating layers disposed on the circuit board; and a metal layer disposed between the plurality of insulating layers. A multilayer printed wiring board consisting of: