CN112533906A

CN112533906A - Benzoxazine compound, curable resin composition, adhesive film, cured product, circuit board, interlayer insulating material, and multilayer printed wiring board

Info

Publication number: CN112533906A
Application number: CN201980051984.7A
Authority: CN
Inventors: 胁冈纱香; 竹田幸平; 林达史; 新土诚实; 大当悠太; 川原悠子
Original assignee: Sekisui Chemical Co Ltd
Current assignee: Sekisui Chemical Co Ltd
Priority date: 2018-09-14
Filing date: 2019-07-23
Publication date: 2021-03-19
Also published as: TWI810337B; TW202012494A; JPWO2020054218A1; JP7474054B2; KR20210057004A; WO2020054218A1

Abstract

The purpose of the present invention is to provide a benzoxazine compound that can be used in a curable resin composition having excellent flexibility before curing and excellent dielectric properties after curing. Further, an object of the present invention is to provide a curable resin composition containing the benzoxazine compound, and 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 benzoxazine compound of the present invention has in the molecule: 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.

Description

Benzoxazine compound, curable resin composition, adhesive film, cured product, circuit board, interlayer insulating material, and multilayer printed wiring board

Technical Field

The present invention relates to a benzoxazine compound that can be used in a curable resin composition having excellent flexibility before curing and excellent dielectric characteristics after curing. The present invention also relates to a curable resin composition containing the benzoxazine compound, and 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.

Background

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

Documents of the prior art

Patent documents:

patent document 1: japanese patent laid-open publication No. 2017-186551

Patent document 2: international publication No. 2016/114286

Disclosure of Invention

Problems to be solved by the invention

The purpose of the present invention is to provide a benzoxazine compound that can be used in a curable resin composition having excellent flexibility before curing and excellent dielectric properties after curing. Further, an object of the present invention is to provide a curable resin composition containing the benzoxazine compound, and 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.

Means for solving the problems

The present invention is a benzoxazine compound having in a molecule: 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.

The present invention will be described in detail below.

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

The benzoxazine compound of the present invention has in the molecule: a diamine residue having an aliphatic skeleton having 4 or more carbon atoms (hereinafter, also simply referred to as "diamine residue") and/or a triamine residue having an aliphatic skeleton having 4 or more carbon atoms (hereinafter, also simply referred to as "triamine residue"). The benzoxazine compound of the present invention has the diamine residue and/or the triamine residue, and therefore, when it is blended in a curable resin composition, the benzoxazine compound can improve the flexibility of the curable resin composition before curing. Further, by providing the benzoxazine compound of the present invention with the diamine residue and/or the triamine residue and having a benzoxazine ring, the cured product of the obtained curable resin composition has excellent dielectric properties such as low dielectric constant and low dielectric loss tangent.

In the present specification, the "residue" refers to a structure of a portion other than the functional group to be bonded, and for example, the "diamine residue" refers to a structure of a portion other than the amino group in the raw diamine.

The lower limit of the number of carbon atoms of the aliphatic skeleton of the diamine residue and the triamine residue is 4. By setting the number of carbon atoms of the aliphatic skeleton included in the diamine residue and the triamine residue to 4 or more, the flexibility before curing and the dielectric characteristics after curing of the obtained curable resin composition are excellent. The lower limit of the number of carbon atoms of the aliphatic skeleton included in the diamine residue and the triamine residue is preferably 7, and more preferably 8.

The preferable upper limit of the number of carbon atoms of the aliphatic skeleton of the diamine residue and the triamine residue is not particularly limited, but the upper limit is substantially 90.

The aliphatic skeleton of the diamine residue and the triamine residue may be substituted.

Examples of the substituent in the case where the aliphatic skeleton of the diamine residue and the triamine residue is substituted include a halogen atom, an aryl group, an alkoxy group, a nitro group, a cyano group and the like.

As the diamine to be a source of the diamine residue, an aliphatic diamine can be used.

Examples of the aliphatic diamine include aliphatic diamines derived from dimer acids, linear or branched aliphatic diamines, aliphatic ether diamines, and alicyclic diamines. Among these, aliphatic diamines derived from dimer acids are preferred.

Examples of the aliphatic diamine derived from the dimer acid include dimer diamines (dimer diamines) derived from dimer acids which are dimers of aliphatic acids having 10 to 30 carbon atoms such as oleic acid, linoleic acid, linolenic acid, palmitoleic acid, and elaidic acid, 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, 1, 11-undecanediamine, 1, 12-dodecanediamine, 1, 14-tetradecanediamine, 1, 16-hexadecanediamine, 1, 18-octadecanediamine, 1, 20-eicosanediamine, 2-methyl-1, 8-octanediamine, 2-methyl-1, 9-nonanediamine, and 2, 7-dimethyl-1, 8-octanediamine.

Examples of the aliphatic ether diamine include 2, 2 '-oxybis (ethylamine), 3' -oxybis (propylamine), 1, 2-bis (2-aminoethoxy) ethane, and the like.

Examples of the alicyclic diamine include 1, 3-bis (aminomethyl) cyclohexane, 1, 4-bis (aminomethyl) cyclohexane, cyclohexanediamine, methylcyclohexanediamine, isophoronediamine, and the like.

As the diamine to be a source of the diamine residue, a diamine obtained by a reaction between the aliphatic diamine and an acid dianhydride and having an acid dianhydride residue in a main chain and amino groups derived from the aliphatic diamine at both ends may be used.

Examples of the acid dianhydride include pyromellitic dianhydride, 3, 3 ' -oxydiphthalic anhydride, 3, 4 ' -oxydiphthalic anhydride, 4 ' - (4, 4 ' -isopropyldiphenoxy) diphthalic anhydride, acid dianhydride of 4, 4 ' -bis (2, 3-dicarboxyphenoxy) diphenyl ether, p-phenylene bis (trimellitic monoester anhydride), and 2, 3, 3 ', 4 ' -biphenyltetracarboxylic anhydride. Among these, 4 '- (4, 4' -isopropyldiphenoxy) diphthalic anhydride is preferable.

As the triamine which becomes the source of the triamine residue, an aliphatic triamine can be used.

Examples of the aliphatic triamine include an aliphatic triamine derived from a trimer acid, a linear or branched aliphatic triamine, and the like. Among these, aliphatic triamines derived from the trimer acid are preferable.

Examples of the aliphatic triamine derived from the trimer acid include a trimer triamine derived from a 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, elaidic acid, and the like, and a hydrogenated trimer triamine thereof.

Examples of the linear or branched aliphatic triamine include 3, 3 ' -diamino-N-methyldipropylamine, 3 ' -diaminodipropylamine, diethylenetriamine, bis (hexamethylene) triamine, and 2, 2 ' -bis (methylamino) -N-methyldiethylamine.

The aliphatic triamine may be used in the form of a mixture with the aliphatic diamine.

Examples of commercially available products of the aliphatic diamine and/or the aliphatic triamine include aliphatic diamine and/or aliphatic triamine manufactured by BASF corporation, aliphatic diamine and/or aliphatic triamine manufactured by Croda corporation, and the like.

Examples of the aliphatic diamine and/or aliphatic triamine manufactured by BASF include Versamine551 and Versamine 552.

Examples of the aliphatic diamine and/or aliphatic triamine manufactured by Croda include primine 1071, primine 1073, primine 1074, and primine 1075.

The benzoxazine compound of the present invention preferably 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) as a structure containing the diamine residue and/or the triamine residue and the benzoxazine ring. The benzoxazine compound 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), and thus has more excellent flexibility before curing and dielectric characteristics after curing.

[ chemical formula 1]

In the formula (1-1), A is the above-mentioned diamine residue, and X' are each independently a hydrogen atom or an optional substituent.

In the formula (1-2), A is the triamine residue, and X, X 'and X' are each independently a hydrogen atom or an optional substituent.

[ chemical formula 2 ]

In the formula (2-1), A is the above-mentioned diamine residue, B and B 'are each independently an arbitrary organic group, R and R' are each independently a hydrogen atom or an arbitrary substituent, B and each R 'may be bonded to form a ring structure, B' and each R 'may be bonded to form a ring structure, and Y' are each independently a hydrogen atom or an arbitrary substituent.

In the formula (2-2), a is the triamine residue, B, B ' and B "are each independently an arbitrary organic group, R, R ' and R" are each independently a hydrogen atom or an arbitrary substituent, B and each R may be bonded to form a ring structure, B ' and each R ' may be bonded to form a ring structure, B "and each R" may be bonded to form a ring structure, and Y, Y ' and Y "are each independently a hydrogen atom or an arbitrary substituent.

[ chemical formula 3 ]

In formula (3), A and A 'are each independently the above-mentioned diamine residue, B is an arbitrary organic group, R and R' are each independently a hydrogen atom or an arbitrary substituent, B and R 'may bond to form a ring structure, and X' are each independently a hydrogen atom or an arbitrary substituent.

When X and X ' in the formula (1-1) and X, X ' and X ' in the formula (1-2) are substituents, examples of the substituents 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, a cyano group and the like.

In addition, when X and X ' in the formula (1-1) and X, X ' and X ' in the formula (1-2) are substituents, the hydrogen atom of the aromatic ring may be substituted with a plurality of the substituents.

When Y and Y ' in the formula (2-1) and Y, Y ' and Y ' in the formula (2-2) are substituents, examples of the substituents include a linear or branched alkyl group, a linear or branched alkenyl group, an alicyclic group, an aryl group, and a phenyl group having an alkyl group or an alkoxy group as a substituent.

In addition, when Y and Y ' in the formula (2-1) and Y, Y ' and Y ' in the formula (2-2) are substituents, the hydrogen atom of the aromatic ring may be substituted with a plurality of the substituents.

Preferably, B and each R in the formula (2-1), and B 'and each R', and B and each R, B 'and each R', and B 'and each R' in the formula (2-2) 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).

[ chemical formula 4 ]

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

When Y and Y' in the formula (4) are a substituent, examples of the substituent include a linear or branched alkyl group, a linear or branched alkenyl group, an alicyclic group, an aryl group, and a phenyl group having an alkyl group or an alkoxy group as a substituent.

In addition, in the case where 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 dianhydride which is the source of the acid dianhydride residues represented by C and C' in formula (4) include the same acid dianhydrides as those used in the reaction of the aliphatic diamine and the acid dianhydride.

When X and X' in the formula (3) are substituents, examples of the substituents 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, a cyano group, and the like.

In addition, in the case where 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.

Preferably, in the formula (3), B and R, and B and R' form a ring structure. The ring structure is preferably an imide ring.

In particular, the structure represented by the above formula (3) is preferably a structure represented by the following formula (5).

[ chemical formula 5 ]

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

When X and X' in the formula (5) are substituents, examples of the substituents 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, a cyano group, and the like.

In addition, in the case where 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 preferably 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. 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), and thus has more excellent flexibility before curing, and dielectric properties and mechanical strength after curing.

[ chemical formula 6 ]

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

[ chemical formula 7 ]

In the formula (7), A is the above-mentioned diamine residue, B and B 'are each independently an arbitrary organic group, R and R' are each independently a hydrogen atom or an arbitrary substituent, B and R may bond to form a ring structure, B 'and R' may bond to form a ring structure, and W is an arbitrary organic group.

[ chemical formula 8 ]

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

Examples of the substituent in the case where the hydrogen atom of the aromatic ring in the formula (6) is substituted with an arbitrary substituent 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, a cyano group and the like.

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

Preferably, in the formula (7), B and each R, and B 'and each R' form a ring structure. The ring structure is preferably an imide ring.

Examples of the substituent in the case where the hydrogen atom of the aromatic ring in the formula (8) is substituted with an arbitrary substituent 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, a cyano group and the like.

Preferably, in the formula (8), B and R, and B and R' 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 20 ten thousand. When the benzoxazine compound of the present invention is used in a curable resin composition, the obtained curable resin composition has more excellent flexibility before curing and excellent dielectric properties of a cured product. A more preferable lower limit and a more preferable upper limit of the molecular weight of the benzoxazine compound of the present invention are 400 ten thousand.

In the present specification, the "molecular weight" is a molecular weight determined from a structural formula for a compound having a definite molecular structure, but may be expressed by a number average molecular weight for a compound having a wide distribution of polymerization degrees and a compound having an indefinite modification site. In the present specification, the "number average molecular weight" is a value obtained by measuring by Gel Permeation Chromatography (GPC) using tetrahydrofuran as a solvent and converting into polystyrene. Examples of the column used for measuring the number average molecular weight in terms of polystyrene by GPC include JAIGEL-2H-A (manufactured by Japan analytical industries, Ltd.).

Examples of the method for producing the benzoxazine compound having the structure represented by the formula (1-1) or the formula (1-2) in the benzoxazine compound of the present invention include a method of reacting the diamine or the triamine, and 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, 2, 6-dimethylphenol, 2-ethylphenol, 3-ethylphenol, 4-tert-butylphenol, p-octylphenol, p-cumylphenol, dodecylphenol, o-phenylphenol, p-phenylphenol, 1-naphthol, 2-naphthol, m-methoxyphenol, p-methoxyphenol, m-ethoxyphenol, p-ethoxyphenol, 3, 4-dimethylphenol, 3, 5-dimethylphenol, and the like. Among them, phenol is preferred.

These monofunctional phenol compounds may be used alone, or 2 or more thereof may be used in combination.

Examples of the method for producing the benzoxazine compound having the structure represented by the formula (2-1) or the formula (2-2) in the benzoxazine compound of the present invention include the following methods.

That is, first, the diamine or the triamine is reacted with an acid dianhydride in an amount of 2 times by mole to obtain an imide oligomer having an acid anhydride group at all terminals. The obtained imide oligomer having an acid anhydride group at all terminals was reacted with 2 times the molar amount of 3-aminophenol, thereby obtaining an imide oligomer having a phenolic hydroxyl group at all terminals. And a method of reacting the obtained imide oligomer or monoamine compound having a phenolic hydroxyl group at all terminals with paraformaldehyde.

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, and 2-naphthylamine, 1-aminoanthracene, 2-aminoanthracene, 9-aminoanthracene, 1-aminopyrene, 3-chloroaniline, o-methoxyaniline, m-methoxyaniline, p-methoxyaniline, 1-amino-2-methylnaphthalene, 4-ethylaniline, 4-ethynylaniline, 4-isopropylaniline, 4- (methylthio) aniline, etc. Among them, aniline is preferred.

As a method for producing the benzoxazine compound having the structure represented by the above formula (3) among the benzoxazine compounds of the present invention, for example, the following method and the like can be exemplified.

That is, first, an acid dianhydride is reacted with 2 times the molar amount of the diamine to obtain an imide oligomer having amino groups at both ends. And a method of reacting the resulting imide oligomer having amino groups at both ends, monofunctional phenol compound, and paraformaldehyde.

As a method for producing the benzoxazine compound having the structure represented by the formula (6) in the benzoxazine compound of the present invention, for example, a method of reacting the diamine and the bifunctional phenol compound with paraformaldehyde may be mentioned.

Examples of the bifunctional phenol compound include 2, 2-bis (4-hydroxy-3, 5-dimethylphenyl) propane, 2-bis (4-hydroxy-3-methylphenyl) propane, 2-bis (4-hydroxyphenyl) butane, 1-bis (4-hydroxyphenyl) cyclohexane, 2-bis (4-hydroxyphenyl) hexafluoropropane, 2-bis (4-hydroxyphenyl) hexafluoropropane, 4' -dihydroxydiphenylsulfone, 2-hydroxyphenyl ether, 1-bis (4-hydroxyphenyl) ethane, 1-bis (4-hydroxyphenyl) -1-phenylethane, 1, 3-bis (2- (4-hydroxyphenyl) -2) propyl) benzene, and mixtures thereof, 1, 4-bis (2- (4-hydroxyphenyl) -2) propyl) benzene, and the like.

In the method for producing the benzoxazine compound having the structure represented by the above formula (6), a monofunctional phenol compound may be used together with the above bifunctional phenol compound.

As the above monofunctional phenol compound, the same monofunctional phenol compound as 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.

As a method for producing the benzoxazine compound having the structure represented by the above formula (7) among the benzoxazine compounds of the present invention, for example, the following method and the like can be mentioned.

That is, first, the diamine is reacted with an acid dianhydride in an amount of 2 times the molar amount thereof to obtain an imide oligomer having an acid anhydride group at both ends. The obtained imide oligomer having an acid anhydride group at both terminals was reacted with 2 times the molar amount of 3-aminophenol to obtain an imide oligomer having a phenolic hydroxyl group at both terminals. A method of reacting the resulting imide oligomer having phenolic hydroxyl groups at both ends, the diamine (a diamine having an aliphatic skeleton having 4 or more carbon atoms) or a diamine having no aliphatic skeleton having 4 or more carbon atoms with paraformaldehyde, or the like.

Examples of the diamine having no aliphatic skeleton having 4 or more carbon atoms include 3, 3 '-diaminodiphenylmethane, 3, 4' -diaminodiphenylmethane, 4 '-diaminodiphenylmethane, 3' -diaminodiphenyl ether, 3, 4 '-diaminodiphenyl ether, 4' -diaminodiphenyl ether, o-phenylenediamine, m-phenylenediamine, p-phenylenediamine, 3 '-diaminodiphenyl sulfone, 4' -diaminodiphenyl sulfone, 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-bis [4- (4-aminophenoxy) phenyl ] propane, 1, 3-bis [2- (4-aminophenyl) -2-propyl ] benzene, 1, 4-bis [2- (4-aminophenyl) -2-propyl ] benzene, 3 '-diamino-4, 4' -dihydroxyphenylmethane, 4 '-diamino-3, 3' -dihydroxyphenylmethane, 3 '-diamino-4, 4' -dihydroxyphenyl ether, bisaminophenylfluorene, bistoluidine fluorene, 4 ' -bis (4-aminophenoxy) biphenyl, 4 ' -diamino-3, 3 ' -dihydroxyphenyl ether, 3 ' -diamino-4, 4 ' -dihydroxybiphenyl, 4 ' -diamino-2, 2 ' -dihydroxybiphenyl, and the like.

As a method for producing the benzoxazine compound having the structure represented by the above formula (8) among the benzoxazine compounds of the present invention, for example, the following method and the like can be exemplified.

That is, first, an acid dianhydride is reacted with 2 times the molar amount of the diamine to obtain an imide oligomer having amino groups at both ends. And a method of reacting the resulting imide oligomer having amino groups at both ends, bifunctional phenol compound and paraformaldehyde.

As the bifunctional phenol compound, the same bifunctional phenol compound as the method for producing a benzoxazine compound having the structure represented by the above formula (6) can be used.

In the method for producing a benzoxazine compound having the structure represented by the above formula (8), a monofunctional phenol compound may be used together with the above bifunctional phenol compound.

The reaction to form the benzoxazine ring of the benzoxazine compound of the present invention may be carried out in a solvent or without a solvent. When the reaction is carried out in a solvent, examples of the reaction solvent to be used include an aromatic nonpolar solvent, a halogen solvent, and the like.

Examples of the aromatic nonpolar solvent include benzene, toluene, xylene, pseudocumene (pseudocumene), mesitylene, and the like.

Examples of the halogen solvent include chloroform and dichloromethane.

Among them, toluene and xylene are preferable, and toluene is more preferable, because of low burden on the environment and human body, high versatility, and low price.

The above solvents may be used alone, or 2 or more thereof may be used in combination.

When the aromatic nonpolar solvent is used as the reaction solvent, an alcohol may be used in combination with the aromatic nonpolar solvent.

The alcohol is not particularly limited, but is preferably an alcohol having a lower boiling point than the aromatic nonpolar 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 preferable.

These alcohols may be used alone, or 2 or more of them may be used in combination.

In the reaction, the reaction solvent may be refluxed. In the reaction for producing the benzoxazine compound, water is produced in the reaction system. The water has an effect of inhibiting the progress of the synthesis reaction of the benzoxazine compound by solvation action, similarly to alcohols. When a solvent that azeotropes with water is used as the synthesis solvent, water produced during the reaction can be removed by azeotropic distillation to the outside of the system in order to efficiently proceed the reaction. In this case, the water produced in the reaction can be distilled off by using, for example, an isobaric dropping funnel with a cock, a diemol condenser, a dean stark apparatus, or the like.

In the reaction for forming the benzoxazine ring of the benzoxazine compound of the present invention, heat treatment is performed at the time of synthesis. Examples of the heating method include a method in which a temperature is raised to a predetermined temperature by using a temperature controller such as an oil bath, and then the temperature is kept constant.

The predetermined temperature in the heat treatment is not particularly limited, but is preferably adjusted so that the temperature of the reaction solution is 50 to 150 ℃. By setting the temperature of the reaction solution to 50 ℃ or higher, the synthesis reaction of the benzoxazine compound can be prevented from slowing down, and the synthesis efficiency can be improved. By setting the temperature of the reaction solution to 150 ℃ or lower, gelation of the reaction solution during the synthesis reaction can be suppressed.

The duration of the heating treatment is not particularly limited, and the heating is preferably continued for about 1 to 10 hours after the start of heating. By setting the duration of the heating treatment to 1 hour or more, the synthesis reaction can be sufficiently performed, and the synthesis yield can be improved. By setting the duration of the heating treatment to 10 hours or less, gelation of the reaction solution and insolubilization of the benzoxazine compound as a composite can be suppressed.

After the completion of the heat treatment, the reaction medium may be released from contact with a temperature controller such as an oil bath and cooled, or the reaction medium may be cooled using a refrigerant or the like.

Examples of the method for removing the benzoxazine compound from the reaction solution after cooling include a poor solvent reprecipitation method, a concentration and solidification method (solvent is distilled off under reduced pressure), a spray drying method, and the like.

A curable resin composition containing the benzoxazine compound of the present invention is also one of the present invention.

The curable resin composition of the present invention contains the benzoxazine compound of the present invention, and thus has excellent flexibility before curing and 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 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 the preferable upper limit is 80 parts by weight. When the content of the benzoxazine compound of the present invention is in this range, the flexibility of the obtained curable resin composition before curing and the dielectric characteristics after curing are more excellent. A more preferable lower limit of the content of the benzoxazine compound of the present invention is 10 parts by weight, and a more preferable upper limit is 60 parts by weight.

The curable resin composition of the present invention may contain a benzoxazine compound other than the benzoxazine compound of the present invention, in addition to the benzoxazine compound of the present invention, within a range not interfering with the object of the present invention.

Examples of the curable resin include epoxy resins, cyanate resins, phenol resins, imide resins, maleimide resins, silicone resins, acrylic resins, and fluorine resins. Among them, the curable resin preferably contains at least 1 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 resins may be used alone or in combination of 2 or more.

Examples of the epoxy resin include bisphenol A type epoxy resins, bisphenol F type epoxy resins, bisphenol E type epoxy resins, bisphenol S type epoxy resins, 2' -diallylbisphenol A type epoxy resins, hydrogenated bisphenol type epoxy resins, propylene oxide-added bisphenol A type epoxy resins, resorcinol type epoxy resins, biphenyl type epoxy resins, thioether type epoxy resins, diphenyl ether type epoxy resins, dicyclopentadiene type epoxy resins, naphthalene type epoxy resin, fluorene type epoxy resin, naphthylene ether type epoxy resin, phenol novolac type epoxy resin, o-cresol novolac type epoxy resin, dicyclopentadiene novolac type epoxy resin, biphenol aldehyde type epoxy resin, naphthol novolac type epoxy resin, glycidylamine type epoxy resin, alkyl polyol type epoxy resin, rubber modified type epoxy resin, glycidyl ester compound, and the like.

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

The 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 preferably 5 parts by weight, and the upper limit is preferably 80 parts by weight. When the content of the curing agent is in this range, the obtained curable resin composition is more excellent in curability and storage stability. The lower limit of the content of the curing agent is more preferably 10 parts by weight, and the upper limit is more preferably 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 imidazole-based curing accelerators, tertiary amine-based curing accelerators, phosphine-based curing accelerators, photobase generators, sulfonium salt-based curing accelerators, and the like. Among them, imidazole curing accelerators are preferred from the viewpoint of curability and storage stability.

The curing accelerator may be used alone, or 2 or more kinds may be used in combination.

The preferable lower limit of the content of the curing accelerator is 0.8 part by weight with respect to 100 parts by weight of the total of the curable resin, the curing agent, and the benzoxazine compound of the present invention. The curing accelerator is contained in an amount of 0.8 parts by weight or more, whereby the effect of shortening the curing time is further excellent. A more preferable lower limit of the content of the curing accelerator is 1 part by weight.

From the viewpoint of adhesiveness and the like, the content of the curing accelerator is preferably 10 parts by weight or more, and more preferably 5 parts by weight or more.

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 has more excellent 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 moisture absorption reflow resistance and plating resistance of the curable resin composition of the present invention are further improved.

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

The inorganic filler may be used alone, or 2 or more kinds may be used in combination.

The lower limit of the average particle diameter of the inorganic filler is preferably 50nm, and the upper limit is preferably 4 μm. When the average particle diameter of the inorganic filler is in this range, the coating property of the obtained curable resin composition is further improved. The lower limit of the average particle diameter of the inorganic filler is more preferably 100nm, and the upper limit is more preferably 3 μm.

The content of the inorganic filler is preferably 50 parts by weight at the lower limit and 500 parts by weight at the upper limit, 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 inorganic filler is in this range, the obtained curable resin composition is more excellent in moisture absorption reflow resistance and plating resistance. The more preferable 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 control agent for the purpose of improving coatability to an adherend and shape retentivity in a short time.

Examples of the flow control agent include fumed silica such as AEROSIL, and layered silicate.

The flow control agent can be used alone, also can be combined with more than 2.

As the flow control agent, a flow control agent having an average particle diameter of less than 100nm is preferably used.

The lower limit of the content of the flow control agent is preferably 0.1 part by weight, and the upper limit is preferably 50 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 flow control agent is in this range, the effects of improving the coatability to an adherend and the shape retention property in a short time are more excellent. The lower limit of the content of the flow control agent is more preferably 0.5 parts by weight, and the upper limit is more preferably 30 parts by weight.

The curable resin composition of the present invention may contain an organic filler for the purpose of relaxing stress, 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 preferable.

The organic fillers may be used alone, or 2 or more of them may be used in combination.

The preferable upper limit of the content of the organic filler is 300 parts by weight with respect to 100 parts by weight of the total of the curable resin, the curing agent, and the benzoxazine compound of the present invention. By setting the content of the organic filler to 300 parts by weight or less, the toughness and the like of the cured product of the obtained curable resin composition are more excellent while maintaining excellent adhesiveness and the like. The content of the organic filler is more preferably 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, and magnesium hydroxide, halogen compounds, phosphorus compounds, and nitrogen compounds. Among them, boehmite type aluminum hydroxide is preferable.

The flame retardants mentioned above may be used alone, or 2 or more of them may be used in combination.

The preferable lower limit of the content of the flame retardant is 5 parts by weight, and the preferable upper limit is 200 parts by weight, with respect to 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 flame retardant is in this range, the obtained curable resin composition has excellent flame retardancy while maintaining excellent adhesiveness and the like. The lower limit of the content of the flame retardant is more preferably 10 parts by weight, and the upper limit is more preferably 150 parts by weight.

The curable resin composition of the present invention may contain a thermoplastic resin within a range not interfering with the object of the present invention. By using the thermoplastic resin, the curable resin composition of the present invention has more excellent flow characteristics, can more easily achieve both filling properties and leaching resistance during thermocompression bonding, and has more excellent bending resistance after curing.

Examples of the thermoplastic resin include polyimide resins, phenoxy resins, polyamide resins, polyamideimide resins, polyvinyl acetal resins, and the like. Among them, phenoxy resins are preferred in terms of heat resistance and handling properties.

The thermoplastic resin can be used alone, also can be combined with more than 2.

The lower limit of the number average molecular weight of the thermoplastic resin is preferably 3000, and the upper limit thereof is preferably 10 ten thousand. When the number average molecular weight of the thermoplastic resin is in this range, the flow characteristics and the bending resistance after curing of the obtained curable resin composition are further improved. The lower limit of the number average molecular weight of the thermoplastic resin is 5000, and the upper limit is 5 ten thousand.

The preferable lower limit of the content of the thermoplastic resin is 2 parts by weight, and the preferable upper limit is 60 parts by weight, with respect to 100 parts by weight of the total of the curable resin, the curing agent, and the benzoxazine compound of the present invention. By setting the content of the thermoplastic resin to 2 parts by weight or more, the flow property and the bending resistance after curing of the obtained curable resin composition are more excellent. By setting the content of the thermoplastic resin to 60 parts by weight or less, the obtained curable resin composition is more excellent in adhesiveness and heat resistance. The lower limit of the content of the thermoplastic resin is more preferably 3 parts by weight, and the upper limit is more preferably 50 parts by weight.

The curable resin composition of the present invention may contain a solvent from the viewpoint of coatability and the like.

The solvent is preferably an apolar solvent having a boiling point of 160 ℃ or less or an aprotic polar solvent having a boiling point of 160 ℃ or less, from the viewpoints of coatability, storage stability, and the like.

Examples of the nonpolar solvent having a boiling point of 160 ℃ or less or the aprotic polar solvent having a boiling point of 160 ℃ or less include ketone solvents, ester solvents, hydrocarbon solvents, halogen solvents, ether solvents, nitrogen-containing solvents, and the like.

Examples of the ketone solvent include acetone, methyl ethyl ketone, methyl isobutyl ketone, and cyclohexanone.

Examples of the ester-based solvent include methyl acetate, ethyl acetate, and isobutyl acetate.

Examples of the hydrocarbon solvent include benzene, toluene, n-hexane, isohexane, cyclohexane, methylcyclohexane, and n-heptane.

Examples of the halogen-based solvent include dichloromethane, chloroform, and trichloroethylene.

Examples of the ether solvent include diethyl ether, tetrahydrofuran, 1, 4-dioxane, 1, 3-dioxolane, and the like.

Examples of the nitrogen-containing solvent include acetonitrile.

Among them, from the viewpoint of handling properties, solubility of the curing agent, and the like, at least 1 selected from ketone solvents having a boiling point of 60 ℃ or higher, ester solvents having a boiling point of 60 ℃ or higher, and ether solvents having a boiling point of 60 ℃ or higher is preferable. Examples of such a solvent include methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone, ethyl acetate, isobutyl acetate, 1, 4-dioxane, 1, 3-dioxolane, and tetrahydrofuran.

The "boiling point" refers to a value measured under a condition of 101kPa, or a value converted to 101kPa using a boiling point conversion chart or the like.

The lower limit of the content of the solvent in the curable resin composition of the present invention is preferably 15% by weight, and the upper limit is preferably 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 lower limit of the content of the solvent is more preferably 20% by weight, and the upper limit is more preferably 70% by weight.

The curable resin composition of the present invention may contain a reactive diluent within a range not interfering with the object of the present invention.

As the reactive diluent, a reactive diluent having 2 or more reactive functional groups in 1 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, a bleeding inhibitor, a flux, a leveling agent, and the like.

Examples of the method for producing the curable resin composition of the present invention include a method of mixing a curable resin, a curing agent, the benzoxazine compound of the present invention, and a solvent added as needed, using a mixer such as a homomixer, a universal mixer, a banbury mixer, or a kneader.

The curable resin composition of the present invention is applied to a substrate film and dried to obtain a curable resin composition film containing the curable resin composition of the present invention, and the curable resin composition film is cured to obtain a cured product.

A cured product obtained by curing the curable resin composition of the present invention is also one aspect of the present invention.

The preferable upper limit of the dielectric loss tangent of the cured product of the curable resin composition of the present invention at 23 ℃ is 0.0045. When the dielectric loss tangent of the cured product at 23 ℃ is in this range, the curable resin composition of the present invention can be preferably used for an interlayer insulating material such as a multilayer printed wiring board. The cured product has a dielectric loss tangent at 23 ℃ of preferably 0.0040 and more preferably 0.0035.

The "dielectric loss tangent" is a value measured at 1.0GHz using a dielectric constant measuring device and a network analyzer. The cured product for measuring the "dielectric loss tangent" can be obtained by heating the curable resin composition film having a thickness of 40 to 200 μm at 190 ℃ for 90 minutes.

The curable resin composition of the present invention can be used in a wide range of applications. For example, the resin composition can be used as an adhesive for a printed wiring board, an adhesive for a coverlay layer of a flexible printed circuit board, a copper-clad laminate, an adhesive for bonding a semiconductor, an interlayer insulating material, a prepreg, an encapsulant for an LED, an adhesive for a structural material, and the like.

Among them, the use in adhesive applications is preferable. An adhesive comprising the curable resin composition of the present invention is also one aspect of the present invention.

The curable resin composition film can be preferably used as an adhesive film. An adhesive film formed using the curable resin composition of the present invention is also one aspect of the present invention.

Further, a circuit board having the cured product of the present invention is also one aspect of the present invention.

The curable resin composition of the present invention can be preferably used as an interlayer insulating material for a multilayer printed wiring board or the like because a cured product thereof has a low dielectric constant, a low dielectric loss tangent and excellent dielectric characteristics. An interlayer insulating material using the curable resin composition of the present invention is also one aspect of the present invention.

A multilayer printed wiring board including a circuit board, a plurality of insulating layers disposed on the circuit board, and a metal layer disposed between the insulating layers, wherein the insulating layers include a cured product of the interlayer insulating material of the present invention is also one aspect of the present invention.

ADVANTAGEOUS EFFECTS OF INVENTION

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

Detailed Description

The present invention will be described in more detail below 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-capacity flask equipped with a reflux tube, an isobaric dropping funnel with a cock and a Dimerosal condenser, 150mL of toluene and 50mL of methanol as a mixed solvent were added at once at 25 ℃ and mixed. Subsequently, 18.8g (0.2 mol) of phenol (manufactured by Tokyo chemical industry Co., Ltd.) and 56.2g (0.1 mol) of primamine 1074 (manufactured by Croda) as a hydrogenated dimer diamine were added to the flask at one time at 25 ℃ and mixed. Then, 13.2g (0.44 mol) of paraformaldehyde (manufactured by Tokyo chemical industry Co., Ltd.) was added to the flask at one time at 25 ℃ and mixed to obtain a mixed solution.

The flask containing the obtained mixed solution was immersed in an oil bath at a temperature of 120 ℃ and heated while refluxing to allow the reaction to proceed. After 1 hour from the start of reflux, water produced in the reaction system was distilled off by azeotroping it with toluene and methanol.

After the reaction was allowed to proceed for 4 hours from the start of the removal by distillation, the flask was taken out of the oil bath, and the resulting reaction solution was cooled to 25 ℃. After cooling, the reaction solution was poured into 1L of methanol to precipitate the reaction product. The precipitated solid was dried under reduced pressure to obtain a benzoxazine compound a.

By the way of illustration¹H-NMR, GPC and FT-IR spectroscopyThe analysis confirmed that the benzoxazine compound a contained a benzoxazine compound having a structure represented by the above formula (1-1) (a was a hydrogenated dimer diamine residue, and X' were hydrogen atoms). In addition, the number average molecular weight of the benzoxazine compound a was 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 56.8g (0.1 mol) of Priamine1073 (manufactured by Croda) as a dimer diamine was used in place of Priamine 1074.

By the way of illustration¹H-NMR, GPC and FT-IR analyses confirmed that the benzoxazine compound B contained a benzoxazine compound having the structure shown in the above formula (1-1) (A was a dimer diamine residue, and X' were hydrogen atoms). In addition, the number average molecular weight of the benzoxazine compound B was 800.

Synthesis example 3 (preparation of benzoxazine Compound C)

A benzoxazine compound C was obtained in the same manner as in Synthesis example 1 except that 61.7g (0.1 mol) of Priamine1071 (manufactured by Croda) as a mixture of dimer diamine and trimer triamine was used in place of Priamine 1074.

By the way of illustration¹H-NMR, GPC, and FT-IR analysis confirmed that the benzoxazine compound C contained a benzoxazine compound having the structure represented by the above formula (1-1) (a was a dimer diamine residue, and X' were hydrogen atoms). In addition, it was confirmed that this benzoxazine compound C contained a benzoxazine compound having a structure represented by the above formula (1-2) (a was a trimer triamine residue, X, X' and X "were hydrogen atoms). In addition, the number average molecular weight of the benzoxazine compound C was 850.

Synthesis example 4 (preparation of benzoxazine Compound D)

56.8g (0.1 mol) of Priamine1073 (manufactured by Croda) as a dimer diamine was dissolved in 400g of N-methylpyrrolidone ("NMP" manufactured by Fuji film and Wako pure chemical industries, Ltd.). To the obtained solution, 104.1g (0.2 mol) of 4, 4 '- (4, 4' -isopropyldiphenoxy) diphthalic anhydride (manufactured by Tokyo chemical industries, Ltd.) as an aromatic tetracarboxylic acid was added, and the mixture was stirred at 25 ℃ for 2 hours to react, thereby obtaining an amic acid oligomer solution. After removing N-methylpyrrolidone from the obtained amic acid oligomer solution under reduced pressure, the resulting amic acid oligomer solution was heated at 300 ℃ for 2 hours to obtain an imide oligomer having acid anhydride groups at both ends.

26.8g (0.2 mol) of 3-aminophenol (manufactured by Tokyo chemical industry Co., Ltd.) was dissolved in 400g of N-methylpyrrolidone (manufactured by Fuji film and Wako pure chemical industries, Ltd. "NMP"). 157.3g (0.1 mol) of an imide oligomer having an acid anhydride group at both ends was added to the obtained solution, and the mixture was stirred at 25 ℃ for 2 hours to react, thereby obtaining an amic acid oligomer solution. After removing N-methylpyrrolidone from the obtained amic acid oligomer solution under reduced pressure, the resulting amic acid oligomer solution was heated at 300 ℃ for 2 hours to obtain an imide oligomer having phenolic hydroxyl groups at both ends.

In a 500 mL-capacity flask equipped with a reflux tube, an isobaric dropping funnel with a cock and a Dimerosal condenser, 150mL of toluene and 50mL of methanol as a mixed solvent were added at once at 25 ℃ and mixed. Next, 174.7g (0.1 mol) of an imide oligomer having a phenolic hydroxyl group at both ends and 18.6g (0.2 mol) of aniline (manufactured by tokyo chemical industry co.) were added to the flask at once at 25 ℃. Then, 13.2g (0.44 mol) of paraformaldehyde (manufactured by Tokyo chemical industry Co., Ltd.) was added to the flask at one time at 25 ℃ and mixed to obtain a mixed solution.

After the reaction was allowed to proceed for 4 hours from the start of the removal by distillation, the flask was taken out of the oil bath, and the resulting reaction solution was cooled to 25 ℃. After cooling, the reaction solution was poured into 1L of methanol to precipitate the reaction product. The precipitated solid was dried under reduced pressure to obtain a benzoxazine compound D.

By the way of illustration¹H-NMR, GPC, and FT-IR analysis confirmed that the benzoxazine compound D contained a benzoxazine compound having the structure shown in the above formula (4) (a was a dimer diamine residue, C and C 'were 4, 4' - (4, 4 '-isopropyldiphenoxy) diphthalic anhydride residues, and Y' were phenyl groups). The number average molecular weight of the benzoxazine compound D was 2000.

Synthesis example 5 (preparation of benzoxazine Compound E)

113.6g (0.2 mol) of Priamine1073 (manufactured by Croda) as a dimer diamine was dissolved in 400g of N-methylpyrrolidone ("NMP" manufactured by Fuji film and Wako pure chemical industries, Ltd.). To the obtained solution, 52.0g (0.1 mol) of 4, 4 '- (4, 4' -isopropyldiphenoxy) diphthalic anhydride (manufactured by Tokyo chemical industries, Ltd.) as an aromatic tetracarboxylic acid was added, and the mixture was stirred at 25 ℃ for 2 hours to react, thereby obtaining an amic acid oligomer solution. After removing N-methylpyrrolidone from the obtained amic acid oligomer solution under reduced pressure, the resulting amic acid oligomer solution was heated at 300 ℃ for 2 hours to obtain an imide oligomer having amino groups at both ends.

In a 500 mL-capacity flask equipped with a reflux tube, an isobaric dropping funnel with a cock and a Dimerosal condenser, 150mL of toluene and 50mL of methanol as a mixed solvent were added at once at 25 ℃ and mixed. Then, 18.8g (0.2 mol) of phenol (manufactured by Tokyo chemical industry Co., Ltd.) and 160.7g (0.1 mol) of the obtained imide oligomer having amino groups at both ends were added to the flask in one portion at 25 ℃ and mixed. Then, 13.2g (0.44 mol) of paraformaldehyde (manufactured by Tokyo chemical industry Co., Ltd.) was added to the flask at one time at 25 ℃ and mixed to obtain a mixed solution.

After the reaction was allowed to proceed for 4 hours from the start of the removal by distillation, the flask was taken out of the oil bath, and the resulting reaction solution was cooled to 25 ℃. After cooling, the reaction solution was poured into 1L of methanol to precipitate the reaction product. The precipitated solid was dried under reduced pressure to obtain a benzoxazine compound E.

By the way of illustration¹It was confirmed by H-NMR, GPC and FT-IR analysis 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 terminals, C is a 4, 4' - (4, 4 '-isopropyldiphenoxy) diphthalic anhydride residue, and X' are 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-capacity flask equipped with a reflux tube, an isobaric dropping funnel with a cock and a Dimerosal condenser, 150mL of toluene and 50mL of methanol as a mixed solvent were added at once at 25 ℃ and mixed. Then, 34.7g (0.1 mol) of 1, 3-bis (2- (4-hydroxyphenyl) -2-propyl) benzene ("bisphenol M" manufactured by Tokyo chemical industry Co., Ltd.) and 56.2g (0.1 mol) of Priamine1074 (manufactured by Croda Co., Ltd.) as a hydrogenated dimer diamine were added to the flask at 25 ℃ in one portion and mixed. Then, 13.2g (0.44 mol) of paraformaldehyde (manufactured by Tokyo chemical industry Co., Ltd.) was added to the flask at one time at 25 ℃ and mixed to obtain a mixed solution.

The flask containing the obtained mixed solution was immersed in an oil bath at 80 ℃ and heated while refluxing to allow the reaction to proceed. After 1 hour from the start of reflux, water produced in the reaction system was distilled off by azeotroping it with toluene and methanol.

After the reaction was allowed to proceed for 4 hours from the start of the removal by distillation, the flask was taken out of the oil bath, and the resulting reaction solution was cooled to 25 ℃. After cooling, the reaction solution was poured into 1L of methanol to precipitate the reaction product. The precipitated solid was dried under reduced pressure to obtain a benzoxazine compound F.

By the way of illustration¹It was confirmed by H-NMR, GPC and FT-IR analysis that the benzoxazine compound F contained a benzoxazine compound having a repeating structural unit represented by the above formula (6) (A was a hydrogenated dimer diamine residue, and Z was a group represented by the following formula (9)). The number average molecular weight of the benzoxazine compound F was 12000.

[ chemical formula 9 ]

In the formula (9), the bonding position is represented by the formula.

Synthesis example 7 (preparation of benzoxazine Compound G)

A benzoxazine compound G was obtained in the same manner as in Synthesis example 1 except that 29.2G (0.1 mol) of 1, 3-bis (3-aminophenoxy) benzene (manufactured by MITSUI FINE CHEMICALS Co., Ltd. "APB-N") which is a diamine having no aliphatic skeleton having 4 or more carbon atoms was used instead of Priamine 1074.

By the way of illustration¹H-NMR, GPC and FT-IR analyses confirmed that the benzoxazine compound G contained a benzoxazine compound in which the moiety corresponding to A in the above formula (1-1) was a 1, 3-bis (3-aminophenoxy) benzene residue and the moieties corresponding to X and X' were hydrogen atoms. In addition, the number average molecular weight of the benzoxazine compound G was 600.

(examples 1 to 7, comparative examples 1 and 2)

Methyl ethyl ketone as a solvent was added to each of the materials at the mixing ratios shown in table 1, and the mixture was stirred at 1200rpm for 4 hours using a stirrer, thereby obtaining a curable resin composition. The compositions in table 1 show solid components other than the solvent.

The obtained curable resin composition was applied to a release-treated surface of a PET film (XG 284, 25 μm thick, manufactured by Toray corporation) using an applicator. Then, the film was dried in a gill oven at 100 ℃ for 5 minutes to volatilize the solvent, thereby obtaining an uncured laminate film having a PET film and a curable resin composition layer having a thickness of 40 μm on the PET film.

< evaluation >

The uncured laminated films obtained in examples and comparative examples were evaluated as follows. The results are shown in Table 1.

(flexibility)

Each of the uncured laminate films obtained in examples and comparative examples was cut into a rectangular shape of 10cm in the longitudinal direction by 5cm in the transverse direction. The film was folded by 90 degrees or 180 degrees 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 confirmed. In the case of bending at 180 degrees, the film is more likely to be broken than in the case of bending at 90 degrees.

Flexibility was evaluated by marking "o" for the case where no crack was present at either of 90 degrees and 180 degrees, by marking "Δ" for the case where no crack was present at either of 180 degrees and 90 degrees, and by marking "x" for the case where no crack was present at either of 90 degrees and 180 degrees.

(dielectric characteristics)

Each of the uncured laminated films obtained in examples and comparative examples was cut into a size of 2mm in width and 80mm in length. The base PET film was peeled from the curable resin composition layer of the uncured laminated film after cutting, and 5 curable resin composition layers were laminated using a laminator to obtain a laminate having a thickness of about 200 μm. The obtained laminate was heated at 190 ℃ for 90 minutes to obtain a cured product. The resulting cured product was measured for dielectric loss tangent at a frequency of 1.0GHz at 23 ℃ by cavity resonance using a cavity resonance perturbation dielectric constant measuring apparatus CP521 (manufactured by Kanto electronic applications and developers) and a network analyzer N5224A PNA (manufactured by Keysight Technologies).

The dielectric loss tangent was "very good" when it was 0.0035 or less, as "good" when it was more than 0.0035 and 0.0040 or less, as "Δ" when it was more than 0.0040 and 0.0045 or less, and as "x" when it was more than 0.0045, and the dielectric properties were evaluated.

(removability of desmearing (removability of residue at bottom of via))

(1) Lamination and semi-curing

Both surfaces of a CCL substrate ("E679 FG" manufactured by hitachi chemical industry) were immersed in a copper surface roughening agent ("mectchbond CZ-8100" manufactured by MEC) to roughen the copper surface. Each of the uncured laminate films obtained in examples and comparative examples was provided on both sides of the CCL substrate from the curable resin composition layer side, and was laminated on both sides of the CCL substrate using a membrane vacuum laminator (product of business corporation, "MVLP-500") to obtain an uncured laminate sample a. The lamination was carried out by reducing the pressure for 20 seconds to a pressure of 13hPa or less and then pressing at 100 ℃ under a pressure of 0.8MPa for 20 seconds.

After the base PET film was peeled from the obtained uncured laminate sample a, the curable resin composition was cured at 170 ℃ for 30 minutes to obtain a semi-cured laminate sample.

(2) Formation of via holes

Using CO₂A laser (manufactured by hitachi Via Mechanics) produced a prepreg laminate B in which a prepreg of a curable resin composition was laminated on a CCL substrate and vias (through holes) were formed in the prepreg, by forming vias (through holes) having an upper end diameter of 60 μm and a lower end (bottom) diameter of 40 μm on the obtained prepreg laminate sample.

(3) Removal treatment of residue at bottom of via

(a) Swelling treatment

The resulting laminate B was put in a Swelling solution (manufactured by Atotech Japan, "spinning Dip Securigant P") at 70 ℃ and shaken for 10 minutes. Then, the substrate was washed with pure water.

(b) Permanganate treatment (roughening treatment and desmearing treatment)

The laminate B after the swelling treatment was placed in a roughened potassium permanganate (manufactured by Atotech Japan Co., Ltd. "Concentrate compact CP") aqueous solution at 80 ℃ and shaken for 30 minutes. Subsequently, the sample was treated with a 25 ℃ washing solution ("Reduction Securigant P" manufactured by Atotech Japan corporation) for 2 minutes, and then washed with pure water, thereby obtaining an evaluation sample 1.

The bottom of the via hole of the evaluation sample 1 was observed by a Scanning Electron Microscope (SEM), and the maximum smear length from the wall surface of the via hole bottom was measured.

The desmear property (removability of residue on the bottom of a pilot hole) was evaluated by designating "very good" for the maximum smear length of less than 2 μm, as "good" for the maximum smear length of 2 μm or more and less than 2.5 μm, as "Δ" for the maximum smear length of 2.5 μm or more and less than 3 μm, and as "x" for the maximum smear length of 3 μm or more.

(plating adhesion)

The semi-cured laminate sample prepared in the same manner as the above-mentioned "desmear property (removability of residue on the bottom of a via hole") "was placed in a Swelling solution (aqueous solution prepared from Atotech Japan, inc." Swelling Dip Securigant P "and sodium hydroxide (fuji film and Wako pure chemical industries, Ltd.) (70 ℃) and shaken for 10 minutes. Then, the substrate was washed with pure water.

The swollen semi-cured laminate sample was placed in an aqueous sodium permanganate roughening solution (an aqueous solution prepared from Atotech Japan corporation, "Concentrate compact CP" and sodium hydroxide (fuji film and wako pure chemical industries, inc.) at 80 ℃ and shaken for 30 minutes. Then, the substrate was washed with a 25 ℃ washing solution (an aqueous solution prepared from "Reduction Securigant P" manufactured by Atotech Japan corporation and sulfuric acid (manufactured by fuji film and wako pure chemical industries, inc.) for 2 minutes, and then further washed with pure water, thereby forming a roughened semi-cured product on the CCL substrate.

The roughened surface of the semi-cured product was treated with an alkaline Cleaner (manufactured by Atotech Japan, clean Securigant 902) at 60 ℃ for 5 minutes, and then degreased and cleaned. After the washing, the semi-cured product was treated with a 25 ℃ pre-dip solution ("Predip Neodant B" manufactured by Atotech Japan) for 2 minutes. Then, the prepreg was treated with an activating solution (manufactured by Atotech Japan, inc. "Activator reagent 834") at 40 ℃ for 5 minutes to attach the palladium catalyst.

Next, the prepreg WAs treated with a 30 ℃ reducing solution ("Reducer Neodant WA" manufactured by Atotech Japan) for 5 minutes, and then placed in a chemical Copper solution ("Basic print MSK-DK", "coater print MSK", "Stabilizer print MSK", or "Reducer Cu" manufactured by Atotech Japan). Electroless plating was performed until the plating thickness reached about 0.5 μm. After the electroless plating, annealing was performed at a temperature of 120 ℃ for 30 minutes in order to remove residual hydrogen. All steps up to the step of electroless plating were performed on a beaker scale with the treatment solution set to 2L while shaking the prepreg.

And performing electrolytic plating on the electroless plating treated semi-solidified material. Copper sulfate solution (aqueous solution prepared from copper sulfate pentahydrate (Fuji film and Wako Junyaku Co., Ltd.), sulfuric acid (Fuji film and Wako Junyaku Co., Ltd.), Basic level Capacide HL (Atotech Japan Co., Ltd.) and calibrator CAPARASSID GS (Atotech Japan Co., Ltd.) was used for electrolytic plating, and 0.6A/cm was passed through the solution²Until the plating thickness reaches about 25 μm. After the electrolytic plating, the semi-cured product was heated at 190 ℃ for 90 minutes to further cure the semi-cured product, thereby obtaining a cured product in which a copper plating layer was laminated on the upper surface.

In the obtained cured product having the copper plating layer laminated thereon, a 10 mm-wide notch was cut in the surface of the copper plating layer. Then, the adhesion strength (90 ℃ peel strength) between the cured product (insulating layer) and the metal layer (copper-plated layer) was measured using a tensile tester ("AG-5000B" manufactured by Shimadzu corporation) at a crosshead speed of 5 mm/min.

The plating adhesion was evaluated by designating the case where the peel strength was 0.50kgf/cm or more as "excellent", the case where the peel strength was 0.45kgf/cm or more and less than 0.50kgf/cm as "o", the case where the peel strength was 0.40kgf/cm or more and less than 0.45kgf/cm as "Δ", and the case where the peel strength was less than 0.40kgf/cm as "x".

[ Table 1]

Industrial applicability

Claims

1. A benzoxazine compound characterized in that,

having in a molecule: 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.

2. The benzoxazine compound of claim 1, wherein the diamine and/or triamine that becomes the source of the diamine residues and/or the triamine residues is an aliphatic diamine and/or triamine derived from dimer acids and/or trimer acids.

3. The benzoxazine compound according to claim 1 or 2, 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),

in the formula (1-1), A is the diamine residue, X and X' are each independently a hydrogen atom or an optional substituent,

in the formula (1-2), A is the triamine residue, X, X 'and X' are each independently a hydrogen atom or an optional substituent,

in the formula (2-1), A is the diamine residue, B and B ' are each independently an arbitrary organic group, R and R ' are each independently a hydrogen atom or an arbitrary substituent, B is optionally bonded to each R to form a ring structure, B ' is optionally bonded to each R ' to form a ring structure, Y and Y ' are each independently a hydrogen atom or an arbitrary substituent,

in the formula (2-2), A is the triamine residue, B, B 'and B' are each independently an arbitrary organic group, R, R 'and R' are each independently a hydrogen atom or an arbitrary substituent, B is optionally bonded to each R to form a ring structure, B 'is optionally bonded to each R' to form a ring structure, B 'is optionally bonded to each R' to form a ring structure, Y, Y 'and Y' are each independently a hydrogen atom or an arbitrary substituent,

in formula (3), a and a 'are each independently the diamine residue, B is an arbitrary organic group, R and R' are each independently a hydrogen atom or an arbitrary substituent, B and R are optionally bonded to form a ring structure, B and R 'are optionally bonded to form a ring structure, and X' are each independently a hydrogen atom or an arbitrary 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, Z is a bonding bond or an arbitrary organic group, a part or all of hydrogen atoms of the aromatic ring in the formula (6) is optionally substituted with an arbitrary substituent,

in the formula (7), A is the diamine residue, B and B 'are each independently an arbitrary organic group, R and R' are each independently a hydrogen atom or an arbitrary substituent, B and R are optionally bonded to form a ring structure, B 'and R' are optionally bonded to form a ring structure, W is an arbitrary organic group,

in formula (8), a and a ' are each independently the diamine residue, B is an arbitrary organic group, R and R ' are each independently a hydrogen atom or an arbitrary substituent, B and R are optionally bonded to form a ring structure, B and R ' are optionally bonded to form a ring structure, Z is a bonding bond or an arbitrary organic group, and a part or all of the hydrogen atoms of the aromatic ring in formula (8) is optionally substituted with an arbitrary substituent.

5. A curable resin composition containing the benzoxazine compound according to claim 1, 2, 3 or 4.

6. The curable resin composition according to claim 5, which contains a curable resin, a curing agent, and the benzoxazine compound according to claim 1, 2, 3 or 4.

7. The curable resin composition according to claim 6, wherein the curable resin comprises 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 comprising 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 comprising 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. A multilayer printed wiring board comprising a circuit board, a plurality of insulating layers disposed on the circuit board, and a metal layer disposed between the insulating layers, wherein the insulating layers comprise a cured product of the interlayer insulating material according to claim 12.