Heat-curable ester resin, production method therefor, heat-curable resin composition, cured object formed therefrom, prepreg, resin sheet, laminate, and material for circuit boards

Abstract

Provided are: a heat-curable resin composition which comes to have excellent low-dielectric characteristics and have excellent heat resistance in applications such as printed wiring boards; and a heat-curable resin which gives the heat-curable resin composition. 　The heat-curable resin comprises a polyaryloxy unit and a polyarylcarbonyl unit, and is characterized by having a reactive-group-containing unit represented by formula (1) as the polyaryloxy unit. In formula (1), R1 represents a C1-C8 hydrocarbon group, R2 represents a hydrogen atom or a C1-C12 hydrocarbon group, Y represents a site of combining with a polyarylcarbonyl unit or represents a reactive group represented by formula (2), 1-99 mol% of all the Y moieties being the reactive group represented by formula (2), R represents a hydrogen atom or a C1-C8 alkyl or alkenyl group, i is an integer of 0-2, and n indicates the number of repetitions and is a number of 0-5 on average.

Description

Thermosetting ester resin, its manufacturing method, thermosetting resin composition, cured product thereof, prepreg, resin sheet, laminate, and circuit board material

[0001] The present invention relates to a thermosetting ester resin having excellent dielectric properties, a method for producing the same, and a thermosetting resin composition, a cured product, a prepreg, a resin sheet, a laminate, and a circuit board material using the same.

[0002] Thermosetting resins have excellent adhesive properties, flexibility, heat resistance, chemical resistance, insulating properties, and curing reactivity, and are therefore used in a wide range of applications, including paints, civil engineering adhesives, casting, electrical and electronic materials, film materials, etc. In particular, thermosetting resins are widely used in printed wiring boards, which are one type of electrical and electronic material, by imparting flame retardancy to them.

[0003] In recent years, information devices have rapidly become smaller and more powerful, and as a result, higher performance is being demanded of materials used in the fields of semiconductors and electronic components. In particular, thermosetting resin compositions used as materials for electric and electronic components are required to have low dielectric properties in response to the trend toward thinner substrates and higher performance.

[0004] In order to achieve such low dielectric properties in a thermosetting resin composition, Patent Document 1 proposes an epoxy resin composition containing, as an essential component, a polyester having an arylcarbonyloxy group at the molecular chain terminal, which polyester is composed of an aromatic polycarboxylic acid residue and an aromatic polyhydroxy compound residue.

[0005] Patent Document 2 proposes an epoxy resin composition containing, as an essential component, an active ester compound obtained by reacting a specific phenolic resin, an aromatic dicarboxylic acid or its halide, and an aromatic monohydroxy compound.

[0006] However, the thermosetting resins disclosed in these documents do not fully satisfy the performance requirements based on the recent trend toward higher functionality, and are insufficient to ensure low dielectric properties and heat resistance.

[0007] On the other hand, Patent Document 3 proposes an epoxy resin composition containing a 2,6-xylenol-dicyclopentadiene type epoxy resin as an essential component.

[0008] Japanese Patent Application Laid-Open No. 2004-277461 Japanese Patent Application Laid-Open No. 2009-235165 Japanese Patent Application Laid-Open No. 5-339341

[0009] Therefore, an object of the present invention is to provide a curable resin composition which exhibits excellent dielectric properties in the cured product and which also has excellent heat resistance for use in printed wiring boards.

[0010] As a result of extensive research into solving the problems, the present inventors have found that the above problems can be solved by a thermosetting resin represented by the following general formula (1), and have thus completed the present invention.

[0011] That is, the present invention is a thermosetting resin comprising a polyaryloxy unit and a polyarylcarbonyl unit, characterized in that the polyaryloxy unit contains a reactive group-containing unit represented by the following formula (1): Here, R1 independently represents a hydrocarbon group having 1 to 8 carbon atoms, R2 independently represents a hydrogen atom or a hydrocarbon group having 1 to 12 carbon atoms, Y independently represents a bonding site with a polyarylcarbonyl unit or a reactive group represented by formula (2), and 1 to 99 mol % of all Ys are reactive groups represented by formula (2), R represents a hydrogen atom or an alkyl or alkenyl group having 1 to 8 carbon atoms, i is an integer from 0 to 2, and n represents the number of repetitions, the average value of which is a number from 0 to 5.

[0012] The polyaryloxy unit contains other polyaryloxy units than the unit represented by the above formula (1), and the other polyaryloxy units are preferably units represented by the following formula (3) and / or formula (4). Here, Ar1 is independently an aromatic ring group selected from the group consisting of a benzene ring, a naphthalene ring, a furan ring, and a biphenyl ring, and these aromatic rings may have, as a substituent, an alkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, an aryl group having 6 to 11 carbon atoms, an aralkyl group having 7 to 12 carbon atoms, an aryloxy group having 6 to 11 carbon atoms, or an aralkyloxy group having 7 to 12 carbon atoms. Ar11 is a divalent hydrocarbon group having 1 to 10 carbon atoms or a divalent group represented by formula (3a). R11 is independently a hydrogen atom or a hydrocarbon group having 1 to 8 carbon atoms. R3 is a direct bond, a hydrocarbon group having 1 to 20 carbon atoms, -CO-, -O-, -S-, -SO ２ -, and -C(CF ３ ) ２ - is a divalent group selected from the group consisting of. m represents the number of repetitions, the average value of which is a number from 1 to 5. r is 1 or 2. k is 0 or 1.

[0013] The thermosetting ester resin may further contain a monoaryloxy unit, and the monoaryloxy unit is preferably a group represented by the following formula (6). Here, Ar2 is independently an aromatic ring group of a benzene ring, a naphthalene ring, a furan ring, or a biphenyl ring, and these aromatic rings may have, as a substituent, an alkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, an aryl group having 6 to 11 carbon atoms, an aralkyl group having 7 to 12 carbon atoms, an aryloxy group having 6 to 11 carbon atoms, or an aralkyloxy group having 7 to 12 carbon atoms. R4 is a direct bond, —CH ２ -, -C(CH ３ ) ２ -, -CH(CH ３ )-, -CO-, -O-, -S-, -SO ２ -, and -C(CF ３ ) ２ - is a divalent group selected from the group consisting of a direct bond, -CH ２ -, -C(CH ３ ) ２ -, -CH(CH ３ )-, and -C(CF ３ ) ２ - is a divalent group selected from the group consisting of , and k is 0 or 1.

[0014] The thermosetting ester resin has a polyarylcarbonyl unit, and the polyarylcarbonyl unit is preferably a unit represented by the following formula (7). Here, Ar3 is independently an aromatic ring group of any one of a benzene ring, a naphthalene ring, a furan ring, and a biphenyl ring, and these aromatic rings may have, as a substituent, an alkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, an aryl group having 6 to 11 carbon atoms, an aralkyl group having 7 to 12 carbon atoms, an aryloxy group having 6 to 11 carbon atoms, or an aralkyloxy group having 7 to 12 carbon atoms. R5 is a direct bond, a hydrocarbon group having 1 to 20 carbon atoms, -CO-, -O-, -S-, -SO ２ -, and -C(CF ３ ) ２ - is a divalent group selected from the group consisting of 1 and 2. k is 0 or 1.

[0015] The present invention is a method for producing the above-mentioned curable ester resin, characterized in that it uses, as raw materials, an aromatic polyhydric hydroxy compound (A1) containing a polyhydric hydroxy compound represented by the following formula (11), an unsaturated group-containing carboxylic acid anhydride (B1) represented by the following formula (12a) or an unsaturated group-containing carboxylic acid halide (B2) represented by the following formula (12b), and an aromatic polyhydric carboxylic acid (C1) represented by the following formula (17a) or an aromatic polyhydric carboxylic acid halide (C2) represented by the following formula (17b). Here, R1, R2, i, and n are each defined as in the above formula (1). Here, R has the same definition as in the above formula (2), and X represents a halogen. Here, Ar3, R5, and k are each defined as in the above formula (7), and X represents a halogen.

[0016] In the above production method, an aromatic monohydroxy compound (A2) may further be contained, and the aromatic monohydroxy compound (A2) is preferably a compound represented by the following formula (16). Here, Ar2, R4, R14, and k are each defined as in the above formula (6).

[0017] The present invention is a thermosetting resin composition containing the above-mentioned thermosetting ester resin as an essential component.

[0018] The present invention relates to a cured product obtained by curing the above-mentioned thermosetting resin composition, and also to a prepreg, a resin sheet, a laminate, and a circuit board material using the above-mentioned thermosetting resin composition.

[0019] When the thermosetting ester resin of the present invention is blended with other thermosetting resins or compounds and cured, the cured product exhibits excellent dielectric properties and provides a thermosetting resin composition with excellent heat resistance for printed wiring board applications, which is particularly suitable for mobile applications, server applications, and the like, where a low dielectric loss tangent is strongly required.

[0020] 1 is a GPC chart of the thermosetting ester resin obtained in Example 1. FIG. 2 is an IR chart of the thermosetting ester resin obtained in Example 1.

[0021] Hereinafter, embodiments of the present invention will be described in detail.

[0022] The thermosetting ester resin of the present invention is composed of polyaryloxy units and polyarylcarbonyl units, and the polyaryloxy units essentially comprise reactive group-containing units represented by formula (1), and may contain monoaryloxy groups. The polyaryloxy units are structural units derived from a raw aromatic polyhydroxy compound containing an aromatic polyhydroxy compound represented by formula (11), and the polyarylcarbonyl units are structural units derived from a raw aromatic polycarboxylic acid (aromatic polycarboxylic acid halide). In this specification, aromatic polyhydroxy compounds and aromatic monohydroxy compounds are sometimes collectively referred to as "aromatic hydroxy compounds." Aromatic polycarboxylic acids or their acid halides and aromatic monocarboxylic acids or their acid halides are sometimes collectively referred to as "aromatic carboxylic acids or their acid halides." When simply referred to as "reactive group," it refers to the reactive group represented by formula (2). In this specification, monoaralkyloxy groups may also be treated as monoaryloxy units (monoaryloxy groups).

[0023] The resin composition obtained from the thermosetting ester resin of the present invention exhibits high heat resistance while exhibiting low dielectric constant and dielectric dissipation factor when cured. Furthermore, since the resin contains ester bonds in its structure, it can also be used as a curing agent for epoxy resins. Furthermore, since highly polar hydroxyl groups are not generated during curing, the resulting cured product can have low dielectric dissipation factor and dielectric constant. Because the resin contains numerous ester bonds within the molecular chain that are reactive with epoxy groups, the cured product has a high crosslink density and high heat resistance (glass transition temperature: Tg).

[0024] The thermosetting ester resin of the present invention must have a reactive group-containing unit represented by formula (1) as a polyaryloxy unit.

[0025] In formula (1), R1 independently represents a hydrocarbon group having 1 to 8 carbon atoms, and is preferably an alkyl group having 1 to 8 carbon atoms, an aryl group having 6 to 8 carbon atoms, an aralkyl group having 7 to 8 carbon atoms, or an allyl group. The alkyl group having 1 to 8 carbon atoms may be linear, branched, or cyclic, and examples thereof include, but are not limited to, a methyl group, an ethyl group, a propyl group, an isopropyl group, an n-butyl group, a t-butyl group, a pentyl group, an isopentyl group, a neopentyl group, a cyclopentyl group, a hexyl group, a methylpentyl group, a dimethylbutane group, a cyclohexyl group, and a methylcyclohexyl group. Examples of aryl groups having 6 to 8 carbon atoms include, but are not limited to, a phenyl group, a tolyl group, a xylyl group, and an ethylphenyl group. Examples of aralkyl groups having 7 to 8 carbon atoms include, but are not limited to, a benzyl group and an α-methylbenzyl group. Among these substituents, from the viewpoints of availability and reactivity when formed into a cured product, a phenyl group and a methyl group are preferred, and a methyl group is particularly preferred. The substitution position of R1 may be any of the ortho-, meta-, and para-positions relative to the oxy group, but the ortho-position is preferred.

[0026] In formula (1), R2 independently represents a hydrogen atom or a hydrocarbon group having 1 to 12 carbon atoms, and is preferably a hydrogen atom, an alkyl group having 1 to 12 carbon atoms, an aryl group having 6 to 12 carbon atoms, an aralkyl group having 7 to 12 carbon atoms, or an allyl group.

[0027] The alkyl group having 1 to 12 carbon atoms may be linear, branched, or cyclic, and examples thereof include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, a sec-butyl group, an isobutyl group, a t-butyl group, an n-pentyl group, an isopentyl group, a neopentyl group, a t-pentyl group, a methylbutyl group, a cyclopentyl group, an n-hexyl group, a methylpentyl group, a dimethylbutyl group, a cyclohexyl group, an n-heptyl group, a methylhexyl group, a dimethylpentyl group, a trimethylbutyl group, an ethylpentyl group, a cyclo ... Examples of alkyl groups include, but are not limited to, cycloheptyl, methylcyclohexyl, n-octyl, isooctyl, methylheptyl, dimethylhexyl, trimethylpentyl, ethylhexyl, cyclooctyl, methylcycloheptyl, dimethylcyclohexyl, ethylhexyl, n-octyl, n-nonyl, n-decyl, n-dodecyl, methylcyclohexyl, ethylcyclohexyl, trimethylcyclohexyl, cyclodecyl, n-undecyl, and cyclododecyl.

[0028] Examples of the aryl group having 6 to 12 carbon atoms include, but are not limited to, a phenyl group, a tolyl group, a xylyl group, an ethylphenyl group, a styryl group, an n-propylphenyl group, an isopropylphenyl group, a mesityl group, an ethynylphenyl group, a naphthyl group, and a vinylnaphthyl group.

[0029] Examples of the aralkyl group having 7 to 12 carbon atoms include, but are not limited to, a benzyl group, an α-methylbenzyl group, a dimethylbenzyl group, a trimethylbenzyl group, a naphthylmethyl group, a phenethyl group, and a 2-phenylisopropyl group.

[0030] Other examples include, but are not limited to, an indanyl group, a norbornyl group, a decahydronaphthyl group, a dicyclopentenyl group represented by the following formula (1a) or (1b), or a cyclopentenyl group represented by the following formula (1c):

[0031] Among these substituents, from the viewpoints of availability and reactivity when formed into a cured product, methyl, phenyl, benzyl, α-methylbenzyl, dicyclopentenyl, and cyclopentenyl are preferred. The substitution position of R2 may be any of the ortho, meta, and para positions relative to the oxy group.

[0032] In formula (1), Y independently represents a bonding site with a polyarylcarbonyl unit or a reactive group represented by the following formula (2), and the reactive group accounts for 1 to 99 mol % of all Y, preferably 10 to 80 mol %, and more preferably 15 to 70 mol %. 40 to 60 mol % is particularly preferred. The reactive group represented by formula (2) below, such as an acrylate group or a methacrylate group, is an α,β-unsaturated carbonyl group and has a conjugated double bond, so it is self-polymerizable and can be cured by itself. In this respect, its reactivity is completely different from that of an allyl group (-CH2-CR=CH2) that does not have a conjugated double bond.

[0033] Here, R represents a hydrogen atom or an alkyl or alkenyl group having 1 to 8 carbon atoms, i represents an integer of 0 to 2, and n represents the number of repetitions, the average of which is a number of 0 to 5.

[0034] In formula (2), R is a hydrogen atom or an alkyl or alkenyl group having 1 to 8 carbon atoms. Examples of the alkyl group include a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, a hexyl group, a heptyl group, and an octyl group. Examples of the alkenyl group include a vinyl group, a reactive group, a butenyl group, a pentenyl group, a hexenyl group, a heptenyl group, and an octenyl group. R is preferably a hydrogen atom or a methyl group.

[0035] In formula (1), i is the number of substituents R1 and is an integer of 0 to 2, preferably 1 or 2, and more preferably 2.

[0036] In formula (1), n ​​is the number of repeats, and is a number of 0 or more, and its average value (number average) is 0 to 5. For the purpose of improving heat resistance, trifunctional or more functional groups are preferred, and therefore n is preferably 1.1 to 4.0, more preferably 1.2 to 3.0.

[0037] The polyaryloxy units may contain units other than the reactive group-containing units represented by formula (1) above, as long as the object of the present invention is not impaired, and such units are preferably units represented by formula (3) and / or formula (4). However, it is desirable that the reactive group-containing polyaryloxy units represented by formula (1) above account for preferably 20 mol % or more, more preferably 30 mol % or more, and even more preferably 50 mol % or more of the total amount of polyaryloxy units constituting the thermosetting ester resin of the present invention.

[0038] When the dicyclopentadienylene group-containing polyaryloxy unit represented by the following formula (3') is contained, the total amount of the reactive group-containing polyaryloxy unit represented by formula (1) and the dicyclopentadienylene group-containing polyaryloxy unit represented by formula (3') is preferably 30 mol % or more, more preferably 50 mol % or more.

[0039] The thermosetting ester resin of the present invention can contain, as the polyaryloxy unit, a unit represented by the following formula (3) in addition to the reactive group-containing unit represented by the above formula (1).

[0040] In formula (3), Ar1 independently represents an aromatic ring group selected from the group consisting of a benzene ring, a naphthalene ring, a furan ring, and a biphenyl ring. These aromatic rings may consist solely of a benzene ring, a naphthalene ring, a furan ring, or a biphenyl ring, or may have a substituent R6. Here, the substituent R6 is an alkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, an aryl group having 6 to 11 carbon atoms, an aralkyl group having 7 to 12 carbon atoms, an aryloxy group having 6 to 11 carbon atoms, or an aralkyloxy group having 7 to 12 carbon atoms.

[0041] In formula (3), Ar11 is a divalent hydrocarbon group having 1 to 10 carbon atoms or a divalent group represented by the following formula (3a), which represents a linking group for a novolak resin. Examples of the divalent hydrocarbon group having 1 to 10 carbon atoms include a methylene group and a dicyclopentadienylene group.

[0042] In formula (1), m represents the number of repeating units, and its average value is 1 to 5, preferably 1.0 to 4.0, more preferably 1.0 to 3.0, and even more preferably 1.0 to 2.0. r represents the number of oxy groups, and is 1 or 2.

[0043] In formula (3a), R11 independently represents a hydrogen atom or a hydrocarbon group having 1 to 8 carbon atoms. Examples of hydrocarbon groups having 1 to 8 carbon atoms include alkyl groups having 1 to 6 carbon atoms and aryl groups having 6 to 8 carbon atoms. Preferred are hydrogen atoms, alkyl groups having 1 to 6 carbon atoms, and aryl groups having 6 to 7 carbon atoms (more preferably 6 carbon atoms), and particularly preferred are hydrogen atoms or alkyl groups having 1 to 3 carbon atoms. Examples of alkyl groups having 1 to 6 carbon atoms include linear, branched, and cyclic alkyl groups. Examples include methyl, ethyl, propyl, isopropyl, butyl, isobutyl, sec-butyl, t-butyl, pentyl, hexyl, and cyclohexyl groups. Among these, branched or cyclic alkyl groups tend to provide higher heat resistance than linear alkyl groups. The number of carbon atoms is preferably 1 to 4 for linear alkyl groups, and 6 for cyclic alkyl groups. From the viewpoint of improving heat resistance, an isopropyl group, an isobutyl group, a t-butyl group, or a cyclohexyl group is preferable, and a t-butyl group or a cyclohexyl group is more preferable. A methyl group is also preferable because it tends to improve flame retardancy.

[0044] Examples of the divalent group represented by formula (3a) include —CH ２ -Ph-CH ２ -, -CH ２ -Ph-Ph-CH ２ -, -CH ２ -Ph-CH ２ -Ph-CH ２ -, -CH ２ -Ph-C(CH ３ ) ２ -Ph-CH ２ -, -CH ２ -Ph-CH(CH ３ )-Ph-CH ２ -, -CH ２ -Ph-CH(C ６ H ５ )-Ph-CH ２-, -CH ２ -Ph-Flu-Ph-CH ２ -, -CH ２ -Np-CH ２ -, -CH ２ -Np-Np-CH ２ -, -CH ２ -Np-CH ２ -Np-CH ２ - and -CH ２ -Np-Flu-Np-CH ２ -, etc. These aromatic rings (Ph, Np, and Flu) may further have, as a substituent, an alkyl group having 1 to 6 carbon atoms, an alkoxy group having 1 to 6 carbon atoms, an aryl group having 6 to 12 carbon atoms, an aryloxy group having 6 to 12 carbon atoms, an aralkyl group having 7 to 12 carbon atoms, or an aralkyloxy group having 7 to 12 carbon atoms. The total number of carbon atoms is 6 to 50, and more preferably 6 to 20. Here, Ph is a phenylene group (-C ６ H ４ -), and Np represents a naphthylene group (-C １０ H ６ -), and Flu represents a fluorenyl group (-C １３ H ８ -), and Ph-Ph represents a biphenylene group. More preferably, it is an unsubstituted, alkyl group-substituted, alkoxy group-substituted, or phenyl group-substituted —CH ２ -Ph-CH ２ -, -CH ２ -Ph-Ph-CH ２ - or -CH ２ -Np-CH ２ -, and more preferably unsubstituted, alkyl group-substituted, alkoxy group-substituted, or phenyl group-substituted -CH ２ -Ph-CH ２ - or -CH ２ -Ph-Ph-CH ２ - is.

[0045] The thermosetting ester resin of the present invention can contain, as the polyaryloxy unit, a unit represented by the following formula (4) in addition to the reactive group-containing unit represented by formula (1). The polyaryloxy unit represented by formula (4) is a generalized formula of units represented by the following formulas (4a) to (4h).

[0046]

[0047] Similarly, the monoaryloxy group represented by formula (6) is a generalization of the monoaryloxy group (a unit in which an oxy group is combined into one) corresponding to formulas (4a) to (4h), and the polyarylcarbonyl unit represented by formula (7) is a generalization of the polyarylcarbonyl unit (a unit in which all oxy groups are replaced with carbonyl groups) corresponding to formulas (4a) to (4h).

[0048] In the formula, R3 has the same meaning as R3 in formula (4). R6 is an alkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, an aryl group having 6 to 11 carbon atoms, an aralkyl group having 7 to 12 carbon atoms, an aryloxy group having 6 to 11 carbon atoms, or an aralkyloxy group having 7 to 12 carbon atoms. p is an integer of 0 to 4, and q is an integer of 0 to 6.

[0049] In formula (4), Ar1 represents an aromatic ring group selected from the group consisting of a benzene ring, a naphthalene ring, a furan ring, and a biphenyl ring. These aromatic rings may consist solely of a benzene ring, a naphthalene ring, a furan ring, or a biphenyl ring, or may have a substituent R6. Here, the substituent R6 is an alkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, an aryl group having 6 to 11 carbon atoms, an aralkyl group having 7 to 12 carbon atoms, an aryloxy group having 6 to 11 carbon atoms, or an aralkyloxy group having 7 to 12 carbon atoms. Ar1 is preferably a phenylene group, a naphthylene group, or an aromatic ring group in which a methyl group or a 1-phenylethyl group is substituted on one of these groups.

[0050] The alkyl group having 1 to 10 carbon atoms may be linear, branched, or cyclic, and examples thereof include a methyl group, an ethyl group, an n-propyl group, an n-butyl group, an n-pentyl group, an n-hexyl group, an n-heptyl group, an n-octyl group, an n-nonyl group, an n-decyl group, an isopropyl group, a sec-butyl group, a t-butyl group, an isopentyl group, a neopentyl group, a t-pentyl group, an isohexyl group, a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, a methylcyclohexyl group, a cyclooctyl group, a dimethylcyclohexyl group, an ethylcyclohexyl group, a trimethylcyclohexyl group, and a cyclodecyl group.

[0051] The alkoxy group having 1 to 10 carbon atoms may be linear, branched, or cyclic, and examples thereof include a methoxy group, an ethoxy group, an n-propoxy group, an n-butoxy group, an n-pentyloxy group, an n-hexyloxy group, an n-heptyloxy group, an n-octyloxy group, an n-nonyloxy group, an n-decyloxy group, an isopropoxy group, a sec-butoxy group, a t-butoxy group, an isopentyloxy group, a neopentyloxy group, a t-pentyloxy group, an isohexyloxy group, a cyclopentyloxy group, a cyclohexyloxy group, a cycloheptyloxy group, a methylcyclohexyloxy group, a cyclooctyloxy group, a dimethylcyclohexyloxy group, an ethylcyclohexyloxy group, a trimethylcyclohexyloxy group, and a cyclodecyloxy group.

[0052] Examples of the aryl group or aryloxy group having 6 to 11 carbon atoms include a phenyl group, a tolyl group, an ethylphenyl group, a xylyl group, a propylphenyl group, a mesityl group, a naphthyl group, a methylnaphthyl group, a phenoxy group, a tolyloxy group, an ethylphenoxy group, a xylyloxy group, a propylphenoxy group, a mesityloxy group, a naphthyloxy group, and a methylnaphthyloxy group.

[0053] Examples of the aralkyl group or aralkyloxy group having 7 to 12 carbon atoms include a benzyl group, a methylbenzyl group, a dimethylbenzyl group, a trimethylbenzyl group, a phenethyl group, a 1-phenylethyl group, a 2-phenylisopropyl group, a naphthylmethyl group, a benzyloxy group, a methylbenzyloxy group, a dimethylbenzyloxy group, a trimethylbenzyloxy group, a phenethyloxy group, a 1-phenylethyloxy group, a 2-phenylisopropyloxy group, and a naphthylmethyloxy group.

[0054] In formula (4) and formulas (4a) to (4h), R3 is a direct bond or a hydrocarbon group having 1 to 20 carbon atoms, —CO—, —O—, —S—, or —SO ２ -, and -C(CF ３ ) ２ - is a divalent group selected from

[0055] Examples of hydrocarbon groups having 1 to 20 carbon atoms include —CH ２ -, -CH(CH ３ ) -, -C ２ H ４ -, -C(CH ３ ) ２-, cyclohexylene group, methylcyclohexylene group, dimethylcyclohexylene group, methylisopropylcyclohexylene group, cyclohexylcyclohexylene group, cyclohexylidene group, methylcyclohexylidene group, dimethylcyclohexylidene group, trimethylcyclohexylidene group, tetramethylcyclohexylidene group, ethylcyclohexylidene group, isopropylcyclohexylidene group, t-butylcyclohexylidene group, phenylcyclohexylidene group, cyclohexylcyclohexylidene group, (methylcyclohexyl)cyclohexylidene group, (ethylcyclohexyl)cyclohexylidene group, (phenyl Examples of divalent groups include a cyclohexyl)cyclohexylidene group, a cyclododecylene group, a cyclopentylidene group, a methylcyclopentylidene group, a trimethylcyclopentylidene group, a cyclooctylidene group, a cyclododecylidene group, a 9H-fluorene-9,9-diyl group, a bicyclo[4.4.0]decylidene group, a bicyclohexanediyl group, a phenylene group, a xylylene group, a phenylmethylene group, a diphenylmethylene group, a norbornylene group, an adamantylene group, a tetrahydrodicyclopentadienylene group, a tetrahydrotricyclopentadienylene group, a norbornane structure, a tetrahydrotricyclopentadiene structure, or the like.

[0056] Preferred R3 is a direct bond, —CH ２ -, -CH(CH ３ ) -, -C(CH ３ ) ２ -, -CO-, -O-, -S-, -SO ２ -, trimethylcyclohexylidene group, cyclooctylidene group, cyclododecylidene group, bicyclohexanediyl group, 9H-fluorene-9,9-diyl group, and phenylmethylene group.

[0057] In formula (4), k is 0 or 1.

[0058] The thermosetting ester resin of the present invention may have a monoaryloxy group at the molecular chain terminal. The monoaryloxy group is preferably a group represented by formula (6). The amount of monoaryloxy groups used is preferably 1 mol % or more, more preferably 10 mol % or more, and even more preferably 20 mol % or more of the aromatic monohydroxy compound, which is the raw material from which the monoaryloxy unit represented by the above formula (6) is derived, relative to the total amount of aromatic hydroxy compounds used as raw materials.

[0059] In formula (6), Ar2 is an aromatic ring group similar to Ar1 in formula (4), and may have the same substituents as Ar1, and the preferred substituents are also the same. R4 is a direct bond, —CH ２ -, -C(CH ３ ) ２ -, -CH(CH ３ )-, -CO-, -O-, -S-, -SO ２ -, and -C(CF ３ ) ２ R14 is a divalent group selected from a direct bond, —CH ２ -, -C(CH ３ ) ２ -, -CH(CH ３ )-, and -C(CF ３ ) ２ - is a divalent group selected from the group consisting of. When R14 is other than a direct bond, the group represented by formula (6) is a monoaralkyloxy group but is treated as a monoaryloxy group. k is 0 or 1.

[0060] The polyarylcarbonyl unit is not particularly limited, but is preferably a unit represented by formula (7). In formula (7), Ar3 is an aromatic ring group similar to Ar1 in formula (4), and may have the same substituents as Ar1, and the preferred substituents are also the same. R5 has the same meaning as R3 in formula (4). k is 0 or 1.

[0061] The aromatic hydroxy compound, which is an essential raw material for synthesizing the thermosetting ester resin, is an aromatic polyhydroxy compound represented by formula (11). In formula (11), R1, R2, i, and n are each defined as in formula (1) above.

[0062] The aromatic hydroxy resin represented by general formula (11) can be obtained, for example, by reacting a substituent-containing phenol represented by the following general formula (5) with dicyclopentadiene in the presence of a Lewis acid such as a boron trifluoride ether catalyst.

[0063]

[0064] In the general formula (5), R1 and i have the same meanings as R1 and i in the general formula (1), respectively, and the preferred substituents are also the same.

[0065] Examples of the substituent-containing phenols include cresol, ethylphenol, propylphenol, isopropylphenol, n-butylphenol, t-butylphenol, pentylphenol, isopentylphenol, neopentylphenol, cyclopentylphenol, hexylphenol, (methylpentyl)phenol, (dimethylbutane)phenol, cyclohexylphenol, phenylphenol, tolylphenol, xylylphenol, benzylphenol, α-methylbenzylphenol, allylphenol, dimethylphenol, diethylphenol, dipropylphenol, diisopropylphenol, di(n-butyl)phenol, di(t-butyl)phenol, dipentylphenol, diisopentylphenol, dineopentylphenol, dicyclopentylphenol, dihexylphenol, dicyclohexylphenol, diphenylphenol, ditolylphenol, dixylylphenol, dibenzylphenol, bis(α-methylbenzyl)phenol, methylethylphenol, methyl-t-butylphenol, methylallylphenol, and tolylphenylphenol. From the viewpoints of availability and reactivity when cured, cresol, phenylphenol, benzylphenol, dimethylphenol, diphenylphenol, and dibenzylphenol are preferred, and cresol, phenylphenol, and dimethylphenol are particularly preferred.

[0066] The substitution position is preferably the ortho position, and 2,6-disubstituted phenols having two substituents and represented by the following general formula (5-1) are more preferred.

[0067] R1 has the same definition as in the general formula (2) above.

[0068] Examples of the 2,6-disubstituted phenols include 2,6-dimethylphenol, 2,6-diethylphenol, 2,6-dipropylphenol, 2,6-diisopropylphenol, 2,6-di(n-butyl)phenol, 2,6-di(t-butyl)phenol, 2,6-dihexylphenol, 2,6-dicyclohexylphenol, 2,6-diphenylphenol, 2,6-ditolylphenol, 2,6-dibenzylphenol, 2,6-bis(α-methylbenzyl)phenol, 2-ethyl-6-methylphenol, 2-allyl-6-methylphenol, 2-tolyl-6-phenylphenol, etc. From the viewpoints of ease of availability and reactivity when formed into a cured product, 2,6-diphenylphenol and 2,6-dimethylphenol are preferred, and 2,6-dimethylphenol is particularly preferred.

[0069] The catalyst used in the above reaction is a Lewis acid, specifically boron trifluoride, boron trifluoride phenol complex, boron trifluoride ether complex, aluminum chloride, tin chloride, zinc chloride, iron chloride, etc., with boron trifluoride ether complex being preferred due to ease of handling. In the case of boron trifluoride ether complex, the amount of catalyst used is 0.001 to 20 parts by mass, preferably 0.1 to 15 parts by mass, and more preferably 0.5 to 12 parts by mass per 100 parts by mass of dicyclopentadiene.

[0070] The ratio of phenols to dicyclopentadiene in the reaction is 0.08 to 0.80 moles, preferably 0.09 to 0.60 moles, more preferably 0.10 to 0.50 moles, even more preferably 0.10 to 0.40 moles, and particularly preferably 0.10 to 0.20 moles of dicyclopentadiene per mole of phenols. This reaction may contain not only the aromatic hydroxy resin represented by general formula (11) but also a structure in which a dicyclopentadiene structure is bonded to a hydroxyl group of a phenol. Within this molar ratio range, a compound containing a large amount of components with n=1 or more can be obtained.

[0071] This reaction is preferably carried out by charging the substituted phenol and the catalyst into a reactor and then adding dicyclopentadiene dropwise over 1 to 10 hours.

[0072] The reaction temperature is preferably 50 to 200° C., more preferably 100 to 180° C., and even more preferably 120 to 160° C. The reaction time is preferably 1 to 10 hours, more preferably 3 to 10 hours, and even more preferably 4 to 8 hours.

[0073] After the reaction is complete, an alkali such as sodium hydroxide, potassium hydroxide, or calcium hydroxide is added to deactivate the catalyst. The resulting product is then dissolved in a solvent such as an aromatic hydrocarbon such as toluene or xylene, or a ketone such as methyl ethyl ketone or methyl isobutyl ketone, washed with water, and the solvent is recovered under reduced pressure to obtain the desired aromatic hydroxy compound. It is preferable to react as much of the dicyclopentadiene as possible, leaving a portion of the substituent-containing phenol unreacted, preferably 10% or less, which is then recovered under reduced pressure.

[0074] In the reaction, if necessary, a solvent such as an aromatic hydrocarbon such as benzene, toluene, or xylene, a halogenated hydrocarbon such as chlorobenzene or dichlorobenzene, or an ether such as ethylene glycol dimethyl ether or diethylene glycol dimethyl ether may be used.

[0075] The hydroxyl group equivalent (g / eq.) of the aromatic hydroxy compound used as a raw material for producing the thermosetting ester resin of the present invention is preferably 150 to 500, more preferably 160 to 400, even more preferably 165 to 300, and most preferably 170 to 250. The average molecular weight is preferably a weight average molecular weight (Mw) of 280 to 1,000, more preferably 300 to 700, and even more preferably 400 to 600, and a number average molecular weight (Mn) of 230 to 1,000, more preferably 300 to 700, and even more preferably 400 to 600. The softening point is preferably 50 to 100°C, and more preferably 60 to 90°C.

[0076] When producing the thermosetting ester resin of the present invention, an aromatic polyhydroxy compound other than the aromatic hydroxy compound represented by the above formula (11) may be used in combination, as long as it does not impair the object of the present invention.

[0077] The aromatic polyhydroxy compound that may be used in combination with the reactive group-containing aromatic hydroxy compound represented by formula (11) is not particularly limited, but aromatic polyhydroxy compounds represented by the following formula (13) and / or formula (14) are preferred. In the formula, Ar1, Ar11, m, and r are each defined as in the above formula (3). In the formula, Ar1, R3, and k are each defined as in the above formula (4).

[0078] Examples of the aromatic hydroxy compound represented by formula (13) include novolac resins such as phenol novolac resin (e.g., Shounol BRG-555 (manufactured by Aica Kogyo Co., Ltd.)), cresol novolac resin (e.g., DC-5 (manufactured by Nippon Steel Chemical & Material Co., Ltd.)), xylenol novolac resin, biphenol novolac resin, aromatic modified phenol novolac resin, naphthol novolac resin, and the like; reaction products of phenols and dicyclopentadiene (dicyclopentadiene-type phenol resin), reaction products of naphthols and dicyclopentadiene (dicyclopentadiene-type naphthol resin), and reaction products of phenols and terpenes. and aralkyl novolak resins such as reaction products of phenols and naphthols with xylylene glycol (terpene-type phenolic resins), reaction products of naphthols and terpenes (terpene-type naphthol resins), condensates of phenols and / or naphthols with xylylene glycol (for example, SN-160, SN-395, SN-485 (all manufactured by Nippon Steel Chemical & Material Co., Ltd.)), condensates of phenols and / or naphthols with isopropenylacetophenone, reaction products of phenols and / or naphthols with divinylbenzene, and condensates of phenols and / or naphthols with biphenyl-based crosslinking agents (for example, MEH-7851 (manufactured by UBE Co., Ltd.)).

[0079] When aromatic polyhydroxy compounds represented by formula (13) having an average value of m exceeding 1.2 are used in large quantities, gelation may occur when the compounds are dissolved in a solvent to synthesize a thermosetting ester resin. Therefore, when aromatic polyhydroxy compounds represented by formula (13) are used in combination, it is preferable to use compounds having an average value of m in the range of 1 to 2. Gelation can be prevented by appropriately adjusting the amount of aromatic polyhydroxy compound represented by formula (14) used depending on the value of m. For example, when m is 2, the amount used is preferably 20 mol% or less based on the total amount of aromatic polyhydroxy compound used. In particular, aromatic polyhydroxy compounds represented by the following formula (13') are preferred. In the formula, m has the same meaning as m in the above formula (3).

[0080] Examples of the aromatic dihydroxy compound represented by formula (14) include dihydroxybenzenes such as catechol, resorcinol, methylresorcinol, hydroquinone, monomethylhydroquinone, dimethylhydroquinone, trimethylhydroquinone, mono-t-butylhydroquinone, and di-t-butylhydroquinone; naphthalenediols such as naphthalenediol, methylnaphthalenediol, and methylmethoxynaphthalenediol; biphenols such as biphenol, dimethylbiphenol, and tetramethylbiphenol; and bisphenols such as bisphenol A, bisphenol F, bisphenol C, bisphenol K, bisphenol Z, bisphenol S, tetramethylbisphenol A, tetramethylbisphenol F, tetramethylbisphenol S, tetramethylbisphenol Z, dihydroxydiphenyl sulfide, 4,4'-thiobis(3-methyl-6-t-butylphenol), bisphenolfluorene, biscresolfluorene, and 9,9-bis(3,5-dimethyl-4-hydroxyphenyl)-9H-fluorene.

[0081] The aromatic monohydroxy compound used in combination is not particularly limited, but an aromatic monohydroxy compound represented by the following formula (16) (where R14 is a direct bond) is preferred. As the aromatic monohydroxy compound, an aromatic monoalcohol compound may be used instead of an aromatic monophenol compound. The aromatic monoalcohol compound that may be used is not particularly limited, but an aromatic monoalcohol compound represented by the following formula (16) (where R14 is other than a direct bond) is preferred.

[0082] In the formula, Ar2, R4, R14, and k are each defined as in the above formula (6).

[0083] Examples of aromatic monohydroxy compounds represented by formula (16) include phenol, o-cresol, m-cresol, p-cresol, 3,5-xylenol, o-phenylphenol, p-phenylphenol, 2-benzylphenol, 4-benzylphenol, 4-(α-cumyl)phenol, octylphenol, α-naphthol, β-naphthol, etc., as well as benzyl alcohol, tolylmethanol, dimethylbenzyl alcohol, biphenylmethanol, benzylbenzyl alcohol, and naphthylmethanol, with α-naphthol, β-naphthol, o-phenylphenol, p-phenylphenol, 4-(α-cumyl)phenol, benzyl alcohol, biphenylmethanol, and naphthylmethanol being preferred. In particular, cured products using thermosetting resins containing α-naphthol, β-naphthol, o-phenylphenol, p-phenylphenol, or 4-(α-cumyl)phenol in combination as a curing agent have particularly low dielectric tangents.

[0084] The thermosetting ester resin of the present invention can be obtained by reacting an aromatic polyhydric hydroxy compound, an unsaturated group-containing carboxylic acid chloride or an unsaturated group-containing carboxylic acid anhydride, and an aromatic polycarboxylic acid or its acid halide, in which the aromatic hydroxy compound represented by the above formula (11) is an essential component.

[0085] Examples of the unsaturated group-containing carboxylic acid anhydride or unsaturated group-containing carboxylic acid halide include vinyl group-containing acid anhydrides represented by general formula (12a) or acid halides represented by general formula (12b). In the formula, R has the same definition as in the above formula (2), and X represents a halogen.

[0086] Examples of the vinyl group-containing acid anhydride of formula (12a) include acrylic anhydride and methacrylic anhydride, with methacrylic anhydride being preferred. Examples of the vinyl group-containing acid halide of formula (12b) include acrylic acid chloride, methacrylic acid chloride, and methacrylic acid bromide, with methacrylic acid chloride and methacrylic acid bromide being preferred.

[0087] Examples of aromatic polycarboxylic acids or acid halides thereof include aromatic dicarboxylic acids or halides thereof represented by the following formula (17), and aromatic tricarboxylic acids or halides thereof such as trimesic acid and trimellitic acid. Aromatic monocarboxylic acids or acid halides thereof may also be used in combination. Chlorine or bromine is generally used as the halogen atom in the aromatic carboxylic acid halide. In the formula, Ar3, R3, and k have the same meanings as Ar3, R3, and k in the above formula (7), respectively.

[0088] Examples of the aromatic dicarboxylic acid represented by the formula (17) include phthalic acid, isophthalic acid, terephthalic acid, 1,4-naphthalenedicarboxylic acid, 2,3-naphthalenedicarboxylic acid, 2,6-naphthalenedicarboxylic acid, 1,6-naphthalenedicarboxylic acid, 2,7-naphthalenedicarboxylic acid, 4,4-biphenyldicarboxylic acid, 4,4'-methylenebisbenzoic acid, 4,4'-carbonylbisbenzoic acid, 4,4'-isopropylidenedibenzoic acid, furandicarboxylic acid, etc. Among these, isophthalic acid chloride and terephthalic acid chloride are preferred from the viewpoint of the balance between solvent solubility and heat resistance.

[0089] Examples of aromatic monocarboxylic acid halides include halides of aromatic monocarboxylic acids represented by the following formula (18): When aromatic monocarboxylic acid halides are used in combination, part of the molecular chain terminals becomes an arylcarbonyloxy group. In the formula, Ar2, R4, and k have the same meanings as Ar2, R4, and k in the above formula (6), respectively. Examples of the aromatic monocarboxylic acid represented by formula (18) include benzoic acid, 1-naphthalenecarboxylic acid, 2-naphthalenecarboxylic acid, biphenylcarboxylic acid, and furancarboxylic acid.

[0090] The reaction of aromatic polyvalent hydroxy compound, unsaturated group-containing carboxylic anhydride or its acid halide, and aromatic polyvalent carboxylic acid or its acid halide can be carried out by reacting aromatic polyvalent hydroxy compound in a solvent in the presence of a basic compound.In this case, it is preferable to charge aromatic polyvalent hydroxy compound, unsaturated group-containing carboxylic anhydride or its acid halide, and aromatic polyvalent carboxylic acid or its acid halide into a reactor, dissolve them, and then add a basic compound to carry out the reaction.The aromatic polyvalent hydroxy compound can also be reacted stepwise with aromatic polyvalent carboxylic acid or its acid halide, and unsaturated group-containing carboxylic anhydride or its acid halide.

[0091] The aromatic polyvalent hydroxy compound, the unsaturated group-containing carboxylic anhydride or acid halide, and the aromatic polyvalent carboxylic acid or acid halide thereof are reacted in such proportions that the total of the unsaturated group-containing carboxylic anhydride or acid halide and the aromatic polyvalent carboxylic acid or acid halide thereof is preferably 0.1 to 2.0 equivalents, more preferably 0.8 to 1.5 equivalents, per equivalent of the phenolic hydroxyl group of the aromatic polyvalent hydroxy compound.

[0092] Examples of alkali catalysts that can be used here include inorganic bases such as sodium hydroxide, potassium hydroxide, potassium carbonate, and sodium carbonate, and organic bases such as triethylamine, diisopropylethylamine, dimethylaminopyridine, and pyridine, and among these, sodium hydroxide and potassium hydroxide are preferred because of their excellent reactivity and cost.

[0093] The reaction can be carried out by mixing an aromatic hydroxy compound with an aromatic carboxylic acid or its acid halide in the presence of an organic solvent and adding the alkali catalyst. The amount of alkali catalyst added is preferably 0.9 to 2.0 moles per mole of the phenolic hydroxyl group of the aromatic hydroxy compound.

[0094] Examples of organic solvents that can be used in the above reaction include toluene, dichloromethane, and chloroform, with toluene being preferred from the viewpoints of cost, availability, and liquid separation. When a hydrophobic organic solvent such as toluene is used, there is a possibility that an aqueous solution of an inorganic base such as sodium hydroxide may separate. Therefore, it is desirable to add a phase transfer catalyst such as tetra-n-butylammonium bromide (TBAB) to rapidly react with the phenolic resin dissolved in the organic solvent.

[0095] After the reaction is completed, the reaction solution is neutralized and washed with water to obtain the desired resin.

[0096] The active ester equivalent of the thermosetting ester resin of the present invention is preferably 200 to 3000 g / eq., more preferably 500 to 2000 g / eq., and even more preferably 500 to 1500 g / eq. If it is less than this range, the dielectric properties may deteriorate, and if it is greater, the heat resistance and adhesiveness may decrease. The active ester group refers to an aryloxycarbonyl group in the thermosetting ester resin.

[0097] The reaction temperature when producing the thermosetting ester resin of the present invention is usually 0 to 150°C, preferably 10 to 50°C. The reaction time is usually 0.5 to 10 hours, preferably 1 to 8 hours, and particularly preferably 1 to 5 hours. A reaction time of 0.5 hours or more allows the reaction to proceed sufficiently, while a reaction time of 10 hours or less makes it possible to keep the amount of by-products produced low.

[0098] When there is a concern about self-polymerization of the vinyl group-containing acid anhydride or acid halide, a polymerization inhibitor such as quinones, nitro compounds, nitrophenols, nitroso compounds, nitrone compounds, phenols, or oxygen may be used.

[0099] After completion of the reaction, the solvent may be distilled off under heating and reduced pressure, or the product may be dissolved directly in a ketone solvent having 4 to 7 carbon atoms (e.g., methyl isobutyl ketone, methyl ethyl ketone, cyclopentanone, cyclohexanone, methylcyclohexanone, etc.) or an aromatic hydrocarbon such as benzene, toluene, or xylene, and washed with water, a lower alcohol such as methanol, or a mixed solvent of these, which has low solubility for the target product, to remove by-produced salts and impurities.

[0100] The production of the thermosetting ester resin of the present invention is usually carried out while blowing an inert gas such as nitrogen into the system (air or liquid). By carrying out the reaction while blowing an inert gas into the system, it is possible to prevent the resulting product from becoming discolored. The amount of inert gas blown in per unit time varies depending on the volume of the reactor used in the reaction, and it is preferable to adjust the amount of inert gas blown in per unit time so that the volume of the reactor can be replaced in, for example, 0.5 to 20 hours.

[0101] By using such a thermosetting ester resin, the thermosetting resin composition of the present invention can be obtained.

[0102] The thermosetting resin composition of the present invention contains the above-mentioned thermosetting ester resin as an essential component, and may contain other thermosetting resins. In the resin composition, part or all of the thermosetting resins is the thermosetting ester resin of the present invention, and the thermosetting resin of the present invention preferably accounts for at least 30% by mass, more preferably 50% by mass or more, and even more preferably 75% by mass or more of the total thermosetting resins. If the amount is less than this, the dielectric properties may be deteriorated.

[0103] The epoxy resin used to obtain the thermosetting resin composition of the present invention may be any ordinary epoxy resin having two or more epoxy groups in the molecule, such as bisphenol A type epoxy resin, bisphenol F type epoxy resin, tetramethylbisphenol F type epoxy resin, hydroquinone type epoxy resin, biphenyl type epoxy resin, bisphenol fluorene type epoxy resin, bisphenol S type epoxy resin, bisthioether type epoxy resin, resorcinol type epoxy resin, biphenyl aralkylphenol type epoxy resin, naphthalenediol type epoxy resin, phenol novolac type epoxy resin, styrenated phenol novolac type epoxy resin, cresol novolac type epoxy resin, alkyl novolac type epoxy resin, bisphenol novolac type epoxy resin, Examples of epoxy resins that can be used include, but are not limited to, cyclopentadiene-type epoxy resins, naphthol novolac-type epoxy resins, β-naphthol aralkyl-type epoxy resins, dinaphthol aralkyl-type epoxy resins, α-naphthol aralkyl-type epoxy resins, trisphenylmethane-type epoxy resins, trisphenylmethane-type epoxy resins, dicyclopentadiene-type epoxy resins other than those of the present invention, alkylene glycol-type epoxy resins, aliphatic cyclic epoxy resins, diaminodiphenylmethane tetraglycidylamine, aminophenol-type epoxy resins, phosphorus-containing epoxy resins, urethane-modified epoxy resins, and oxazolidone ring-containing epoxy resins. These epoxy resins may be used alone or in combination of two or more.

[0104] From the viewpoint of availability, it is preferable to use naphthalenediol-type epoxy resins, phenol novolac-type epoxy resins, aromatic-modified phenol novolac-type epoxy resins, cresol novolac-type epoxy resins, α-naphthol aralkyl-type epoxy resins, dicyclopentadiene-type epoxy resins, phosphorus-containing epoxy resins, and oxazolidone ring-containing epoxy resins.

[0105] In addition to the thermosetting ester resin of the present invention, one or more commonly used curing agents such as various phenolic resins, acid anhydrides, amines, hydrazides, and acidic polyesters may be used in combination as needed. When these curing agents are used in combination, the amount of the combined curing agent is preferably 70% by mass or less, more preferably 50% by mass or less, and even more preferably 25% by mass or less, of the total curing agents. If the proportion of the combined curing agent is too high, the dielectric properties of the thermosetting resin composition may be deteriorated.

[0106] In the thermosetting resin composition of the present invention, the active hydrogen groups of the curing agent are preferably 0.2 to 1.5 mol per mol of epoxy groups of the epoxy resin, more preferably 0.3 to 1.4 mol, even more preferably 0.5 to 1.3 mol, and particularly preferably 0.8 to 1.2 mol, per mol of epoxy groups of the epoxy resin. Outside this range, curing may be incomplete, resulting in poor curing properties. For example, when a phenolic resin-based curing agent or an amine-based curing agent is used in combination, the active hydrogen groups are blended in an approximately equimolar amount relative to the epoxy groups. When an acid anhydride-based curing agent is used in combination, the acid anhydride groups are blended in an amount of 0.5 to 1.2 mol, preferably 0.6 to 1.0 mol, per mol of epoxy groups. When the thermosetting resin of the present invention is used alone as a curing agent, the amount used is in the range of 0.5 to 1.5 mol, preferably 0.9 to 1.1 mol, per mol of epoxy resin.

[0107] The active hydrogen group in the present invention refers to a functional group having active hydrogen reactive with an epoxy group (including a functional group having latent active hydrogen that generates active hydrogen by hydrolysis or the like, and a functional group that exhibits an equivalent curing action), and specific examples thereof include an ester group, an acid anhydride group, a carboxyl group, an amino group, and a phenolic hydroxyl group. Note that, with regard to the active hydrogen group, 1 mole of a carboxyl group or a phenolic hydroxyl group is 1 mole of an amino group (NH ２ ) is calculated as 2 moles. If the active hydrogen group is unclear, the active hydrogen equivalent can be determined by measurement. For example, the active hydrogen equivalent of the curing agent used can be determined by reacting a monoepoxy resin such as phenyl glycidyl ether, whose epoxy equivalent is known, with a curing agent whose active hydrogen equivalent is unknown, and measuring the amount of monoepoxy resin consumed.

[0108] Specific examples of the phenolic resin-based curing agent that can be used in combination with the thermosetting resin composition of the present invention include bisphenols such as bisphenol A, bisphenol F, bisphenol C, bisphenol K, bisphenol Z, bisphenol S, tetramethylbisphenol A, tetramethylbisphenol F, tetramethylbisphenol S, tetramethylbisphenol Z, dihydroxydiphenyl sulfide, and 4,4'-thiobis(3-methyl-6-t-butylphenol); dihydroxybenzenes such as catechol, resorcinol, methylresorcinol, hydroquinone, monomethylhydroquinone, dimethylhydroquinone, trimethylhydroquinone, mono-t-butylhydroquinone, and di-t-butylhydroquinone; dihydroxynaphthalene (naphthalenediol), dihydroxymethylnaphthalene (methylnaphthalenediol), dihydroxydimethylnaphthalene (dimethylnaphthalenediol), and dihydroxymethylmethoxynaphthalene (methylmethoxynaphthalenediol); phenol compounds such as phenol compounds called novolak phenol resins, such as condensates of phenols, naphthols, and / or bisphenols with aldehydes, condensates of phenols, naphthols, and / or bisphenols with xylylene glycol, condensates of phenols and / or naphthols with isopropenylacetophenone, reaction products of phenols, naphthols, and / or bisphenols with dicyclopentadiene, and condensates of phenols, naphthols, and / or bisphenols with biphenyl-based crosslinking agents, such as phenol novolak resin, cresol novolak resin, aromatic-modified phenol novolak resin, bisphenol A novolak resin, trishydroxyphenylmethane novolak resin, Resitop TPM-100 (Gunei Chemical Industry Co., Ltd.), naphthol novolak resin, and the like. From the viewpoint of availability, phenol novolac resin, dicyclopentadiene type phenol resin, trishydroxyphenylmethane type novolac resin, aromatic modified phenol novolac resin, etc. are preferred.

[0109] In the case of novolac phenolic resins, examples of phenols include phenol, cresol, xylenol, butylphenol, amylphenol, nonylphenol, butylmethylphenol, trimethylphenol, phenylphenol, etc., examples of naphthols include 1-naphthol, 2-naphthol, etc., and other examples include the above-mentioned bisphenols. Examples of aldehydes include formaldehyde, acetaldehyde, propylaldehyde, butyraldehyde, valeraldehyde, capronaldehyde, benzaldehyde, chloraldehyde, bromaldehyde, glyoxal, malonaldehyde, succinaldehyde, glutaraldehyde, adipic aldehyde, pimelic aldehyde, sebacic aldehyde, acrolein, crotonaldehyde, salicylic aldehyde, phthalaldehyde, hydroxybenzaldehyde, etc. Examples of biphenyl-based crosslinking agents include bis(methylol)biphenyl, bis(methoxymethyl)biphenyl, bis(ethoxymethyl)biphenyl, and bis(chloromethyl)biphenyl.

[0110] Specific examples of the acid anhydride curing agent include methyltetrahydrophthalic anhydride, hexahydrophthalic anhydride, pyromellitic anhydride, phthalic anhydride, trimellitic anhydride, and methylnadic acid.

[0111] Specific examples of the amine-based curing agent include diethylenetriamine, triethylenetetramine, metaxylenediamine, isophoronediamine, diaminodiphenylmethane, diaminodiphenylsulfone, diaminodiphenylether, benzyldimethylamine, 2,4,6-tris(dimethylaminomethyl)phenol, dicyandiamide, and amine-based compounds such as polyamidoamines, which are condensates of acids such as dimer acid and polyamines.

[0112] Specific examples of other curing agents include phosphine compounds such as triphenylphosphine, phosphonium salts such as tetraphenylphosphonium bromide, imidazoles such as 2-methylimidazole, 2-phenylimidazole, 2-ethyl-4-methylimidazole, 2-undecylimidazole, and 1-cyanoethyl-2-methylimidazole, imidazole salts which are salts of imidazoles with trimellitic acid, isocyanuric acid, boron, or the like, quaternary ammonium salts such as trimethylammonium chloride, diazabicyclo compounds, salts of diazabicyclo compounds with phenols, phenol novolac resins, or the like, complex compounds of boron trifluoride with amines, ether compounds, or the like, aromatic phosphonium, or iodonium salts.

[0113] Examples of the curing accelerator include amines, imidazoles, organic phosphines, Lewis acids, and organic peroxides. Specific examples include tertiary amines such as 1,8-diazabicyclo(4,4,0)undecene-7, triethylenediamine, benzyldimethylamine, triethanolamine, dimethylaminoethanol, 4-dimethylaminopyridine, 2-(dimethylaminomethyl)phenol, and tris(dimethylaminomethyl)phenol; imidazoles such as 2-methylimidazole, 2-ethylimidazole, 2-phenylimidazole, 2-ethyl-4-methylimidazole, 1-benzyl-2-methylimidazole, 2-phenyl-4-methylimidazole, 2-heptadecylimidazole, and 2-undecylimidazole; tributylphosphine, methyldiphenylphosphine, and triphenyl Examples of suitable additives include organic phosphines such as phosphine, diphenylphosphine, phenylphosphine, tricyclohexylphosphine, and triphenylphosphine triphenylborane; addition reaction products of organic phosphines with quinone compounds; tetra-substituted phosphonium tetra-substituted borates such as tetraphenylphosphonium tetraphenylborate, tetraphenylphosphonium ethyltriphenylborate, and tetrabutylphosphonium tetrabutylborate; tetraphenylboron salts such as 2-ethyl-4-methylimidazole tetraphenylborate and N-methylmorpholine tetraphenylborate; and organic peroxides such as ketone peroxides, peroxyketals, hydroperoxides, dialkyl peroxides, diacyl peroxides, peroxydicarbonates, and peroxyesters. The amount added is in the range of 0.2 to 5 parts by mass per 100 parts by mass of the resin composition.

[0114] If necessary, a known, commonly used epoxy resin curing accelerator can be used in the thermosetting resin composition of the present invention. Examples of usable curing accelerators include urea compounds such as 3-phenyl-1,1-dimethylurea, 3-(3-methylphenyl)-1,1-dimethylurea, chlorophenylurea, 3-(3-chlorophenyl)-1,1-dimethylurea, and 3-(3,4-dichlorophenyl)-1,1-dimethylurea; quaternary phosphonium salts such as TBP-DA, TBP-3PC, TBP-3S, and TPP-phthalic acid manufactured by Hokko Chemical Industry Co., Ltd.; and metal compounds such as tin octylate. These curing accelerators may be used alone or in combination of two or more. Among these, 4-dimethylaminopyridine and imidazoles are preferred.

[0115] When a curing accelerator is used, the amount used may be appropriately selected depending on the intended use, but 0.01 to 15 parts by mass is used as needed, preferably 0.02 to 10 parts by mass, more preferably 0.05 to 8 parts by mass, and even more preferably 0.1 to 5 parts by mass, per 100 parts by mass of the epoxy resin component in the thermosetting resin composition. Use of a curing accelerator can lower the curing temperature and shorten the curing time.

[0116] A maleimide compound can be used in the thermosetting resin composition of the present invention, if necessary. The maleimide compound that can be used is not particularly limited as long as it is a compound having one or more maleimide groups in one molecule. For example, N-phenylmaleimide, phenylmethanemaleimide, N-hydroxyphenylmaleimide, 4,4'-diphenylmethane bismaleimide, 4,4-diphenylether bismaleimide, polyphenylmethanemaleimide, m-phenylenebismaleimide, p-phenylenebismaleimide, 2,2'-[4-(3-maleimidophenoxy)phenyl]propane, 3,3'-dimethyl-5,5'-diethyl-4,4'-diphenylmethane bismaleimide, bis(3,5-dimethyl-4-maleimidophenyl)methane, bis-(3-ethyl-5-methyl-4-maleimidophenyl) Examples of suitable maleimide compounds include methane, bis(3,5-diethyl-4-maleimidophenyl)methane, 4-methyl-1,3-phenylene bismaleimide, 4,4'-diphenyl ether bismaleimide, 4,4'-diphenylsulfone bismaleimide, 1,3-bis(3-maleimidophenoxy)benzene, 1,3-bis(3-maleimidophenoxy)benzene, N,N'-ethylene dimaleimide, N,N'-hexamethylene dimaleimide, maleimide compounds represented by the following general formula (19), prepolymers of these maleimide compounds, and prepolymers of maleimide compounds and amine compounds. These maleimide compounds can be used alone or in combination of two or more. Among these, the maleimide compounds represented by the following general formula (19) are preferred. Here, R7 independently represents an alkyl group or an aromatic group having 1 to 5 carbon atoms. R8 independently represents a hydrogen atom or a methyl group. a represents an integer of 0 to 4, preferably 0 or 1. b represents an integer of 0 to 3, preferably 0 or 1. c and d are 0 or 1. e is the number of repetitions, the average value of which is 1 to 10, preferably 1 to 7, and more preferably 1 to 5.

[0117] The resin composition of the present invention may contain one or more allyl ether compounds as needed. However, the thermosetting resin of the present invention preferably accounts for 30% by mass, and more preferably 50% by mass or more. If the content is less than this, the dielectric properties may be deteriorated.

[0118] Examples of allyl ether compounds that can be used in combination with the thermosetting resin of the present invention include allyl ether compounds obtained by allyl etherifying bisphenols such as bisphenol A, bisphenol F, bisphenol C, bisphenol K, bisphenol Z, bisphenol S, tetramethylbisphenol A, tetramethylbisphenol F, tetramethylbisphenol S, tetramethylbisphenol Z, dihydroxydiphenyl sulfide, and 4,4'-thiobis(3-methyl-6-t-butylphenol); allyl ether compounds obtained by allyl etherifying dihydroxybenzenes such as catechol, resorcinol, methylresorcinol, hydroquinone, monomethylhydroquinone, dimethylhydroquinone, trimethylhydroquinone, mono-t-butylhydroquinone, and di-t-butylhydroquinone; allyl ether compounds obtained by allyl etherifying hydroxynaphthalenes such as dihydroxynaphthalene, dihydroxymethylnaphthalene, dihydroxymethylnaphthalene, and trihydroxynaphthalene; and Shounol BRG-555 (manufactured by AICA Kogyo Co., Ltd.). phenol novolac resins such as DC-5 (manufactured by Nippon Steel Chemical & Material Co., Ltd.), cresol novolac resins such as DC-5 (manufactured by Nippon Steel Chemical & Material Co., Ltd.), aromatic modified phenol novolac resins, bisphenol A novolac resins, trishydroxyphenylmethane novolac resins such as Resitop TPM-100 (manufactured by Gunei Chemical Industry Co., Ltd.), naphthol novolac resins and other condensates of phenols, naphthols and / or bisphenols with aldehydes, phenols such as SN-160, SN-395, SN-485 (manufactured by Nippon Steel Chemical & Material Co., Ltd.), Examples of such phenolic resins include allyl ether compounds obtained by allylic etherifying polyhydric hydroxy resins known as novolak phenolic resins, such as condensates of phenols, naphthols and / or bisphenols with xylylene glycol, condensates of phenols and / or naphthols with isopropenylacetophenone, reaction products of phenols, naphthols and / or bisphenols with dicyclopentadiene, and condensates of phenols, naphthols and / or bisphenols with a biphenyl-based crosslinking agent; and triallyl isocyanurate.From the viewpoints of reactivity and availability, allyl ether compounds obtained by allylic etherification of bisphenols such as bisphenol A and bisphenol F are preferred.

[0119] The thermosetting resin composition may contain an organic solvent or a reactive diluent for adjusting viscosity.

[0120] Examples of organic solvents include amides such as N,N-dimethylformamide and N,N-dimethylacetamide, ethers such as ethylene glycol monomethyl ether, dimethoxydiethylene glycol, ethylene glycol diethyl ether, diethylene glycol diethyl ether and triethylene glycol dimethyl ether, ketones such as acetone, methyl ethyl ketone, methyl isobutyl ketone and cyclohexanone, alcohols such as methanol, ethanol, 1-methoxy-2-propanol, 2-ethyl-1-hexanol, benzyl alcohol, ethylene glycol, propylene glycol, butyl diglycol and pine oil, and vinegar. Examples of suitable solvents include acetate esters such as butyl acetate, methoxybutyl acetate, methyl cellosolve acetate, cellosolve acetate, ethyl diglycol acetate, propylene glycol monomethyl ether acetate, carbitol acetate, and benzyl alcohol acetate; benzoate esters such as methyl benzoate and ethyl benzoate; cellosolves such as methyl cellosolve, cellosolve, and butyl cellosolve; carbitols such as methyl carbitol, carbitol, and butyl carbitol; aromatic hydrocarbons such as benzene, toluene, and xylene; dimethyl sulfoxide, acetonitrile, and N-methylpyrrolidone, but are not limited to these.

[0121] Examples of reactive diluents include monofunctional glycidyl ethers such as allyl glycidyl ether, butyl glycidyl ether, 2-ethylhexyl glycidyl ether, phenyl glycidyl ether, and tolyl glycidyl ether; bifunctional glycidyl ethers such as resorcinol diglycidyl ether, neopentyl glycol diglycidyl ether, 1,4-butanediol diglycidyl ether, 1,6-hexanediol diglycidyl ether, cyclohexanedimethanol diglycidyl ether, and propylene glycol diglycidyl ether; polyfunctional glycidyl ethers such as glycerol polyglycidyl ether, trimethylolpropane polyglycidyl ether, trimethylolethane polyglycidyl ether, and pentaerythritol polyglycidyl ether; glycidyl esters such as neodecanoic acid glycidyl ester; and glycidyl amines such as phenyl diglycidyl amine and tolyl diglycidyl amine, but are not limited to these.

[0122] These organic solvents or reactive diluents are preferably used alone or in combination in an amount of 90% by mass or less in terms of nonvolatile content, with the appropriate type and amount being selected appropriately depending on the application. For example, for printed wiring board applications, polar solvents with a boiling point of 160°C or less, such as methyl ethyl ketone, acetone, and 1-methoxy-2-propanol, are preferred, with the amount used being 40 to 80% by mass in terms of nonvolatile content. For adhesive film applications, for example, ketones, acetate esters, carbitols, aromatic hydrocarbons, dimethylformamide, dimethylacetamide, and N-methylpyrrolidone are preferred, with the amount used being 30 to 60% by mass in terms of nonvolatile content.

[0123] The thermosetting resin composition may contain other thermosetting resins or thermoplastic resins to the extent that the properties are not impaired. Examples of such resins include, but are not limited to, phenolic resins, acrylic resins, petroleum resins, indene resins, coumarone-indene resins, phenoxy resins, polyurethane resins, polyester resins, polyamide resins, polyimide resins, polyamideimide resins, polyetherimide resins, polyphenylene ether resins, modified polyphenylene ether resins, polyethersulfone resins, polysulfone resins, polyetheretherketone resins, polyphenylene sulfide resins, and polyvinyl formal resins.

[0124] The thermosetting resin composition of the present invention can be blended with vinyl resins and other thermosetting resins, such as vinyl ester resins, polyvinylbenzyl resins, polyallyl resins, epoxy resins, oxetane resins, maleimide resins, acrylate resins, polyester resins, polyurethane resins, polycyanate resins, phenolic resins, and benzoxazine resins.

[0125] It is also possible to compound thermoplastic resins such as polystyrene resin, polyphenylene ether resin, polyetherimide resin, polyethersulfone resin, PPS resin, polycyclopentadiene resin, and polycycloolefin resin; thermoplastic elastomers such as styrene-ethylene-propylene copolymer, styrene-ethylene-butylene copolymer, styrene-butadiene copolymer, styrene-isoprene copolymer, hydrogenated styrene-butadiene copolymer, and hydrogenated styrene-isoprene copolymer; and rubbers such as polybutadiene and polyisoprene.

[0126] When the vinyl resin to be blended is one or more vinyl compounds having one or more polymerizable unsaturated hydrocarbon groups in the molecule, the type of vinyl compound is not particularly limited. That is, the vinyl compound may be any vinyl compound that can form crosslinks and harden by reacting with the thermosetting resin of the present invention. The polymerizable unsaturated hydrocarbon group is preferably a carbon-carbon unsaturated double bond, and more preferably a compound having two or more carbon-carbon unsaturated double bonds in the molecule.

[0127] The average number of carbon-carbon unsaturated double bonds (the number of vinyl groups (including substituted vinyl groups); also referred to as the number of terminal double bonds) per molecule of vinyl compounds as curable resins varies depending on the Mw of the vinyl compounds, but is, for example, preferably 1 to 20, and more preferably 2 to 18. If the number of terminal double bonds is too small, it tends to be difficult to obtain a cured product with sufficient heat resistance. If the number of terminal double bonds is too large, the reactivity becomes too high, and problems such as reduced storage stability and reduced fluidity of the composition may occur.

[0128] Examples of vinyl compounds include trialkenyl isocyanurate compounds such as triallyl isocyanurate (TAIC), modified polyphenylene ethers (PPE) whose terminals are modified with (meth)acryloyl or styryl groups, polyfunctional (meth)acrylate compounds having two or more (meth)acryloyl groups in the molecule, vinyl compounds having two or more vinyl groups in the molecule (polyfunctional vinyl compounds) such as polybutadiene, and vinylbenzyl compounds such as styrene and divinylbenzene. Among these, compounds having two or more carbon-carbon double bonds in the molecule are preferred, and specific examples include TAIC, polyfunctional (meth)acrylate compounds, modified PPE resins, polyfunctional vinyl compounds, and divinylbenzene compounds. The use of these compounds is believed to more favorably form crosslinks through the curing reaction, thereby further enhancing the heat resistance of the cured resin composition. These compounds may be used alone or in combination of two or more. A compound having one carbon-carbon unsaturated double bond in the molecule may also be used in combination. Examples of compounds having one carbon-carbon unsaturated double bond in the molecule include compounds having one vinyl group in the molecule (monovinyl compounds).

[0129] Various known flame retardants can be used in the thermosetting resin composition to improve the flame retardancy of the resulting cured product. Examples of flame retardants that can be used include halogen-based flame retardants, phosphorus-based flame retardants, nitrogen-based flame retardants, silicone-based flame retardants, inorganic flame retardants, and organic metal salt-based flame retardants. From an environmental perspective, halogen-free flame retardants are preferred, and phosphorus-based flame retardants are particularly preferred. These flame retardants may be used alone or in combination of two or more.

[0130] The phosphorus-based flame retardant may be either an inorganic phosphorus-based compound or an organic phosphorus-based compound, such as red phosphorus, ammonium phosphates such as monoammonium phosphate, diammonium phosphate, triammonium phosphate, and ammonium polyphosphate, or inorganic nitrogen-containing phosphorus compounds such as phosphoric acid amide. Examples of the organic phosphorus compounds include general-purpose organic phosphorus compounds such as aliphatic phosphoric acid esters, phosphoric acid ester compounds, condensed phosphoric acid esters such as PX-200 (manufactured by Daihachi Chemical Industry Co., Ltd.), phosphonic acid compounds, phosphinic acid compounds, phosphine oxide compounds, phosphorane compounds, and organic nitrogen-containing phosphorus compounds; metal salts of phosphinic acid; and cyclic organic phosphorus compounds such as 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide, 10-(2,5-dihydroxyphenyl)-10H-9-oxa-10-phosphaphenanthrene-10-oxide, and 10-(2,7-dihydroxynaphthyl)-10H-9-oxa-10-phosphaphenanthrene-10-oxide; and phosphorus-containing epoxy resins and phosphorus-containing curing agents, which are derivatives of these compounds obtained by reacting them with compounds such as epoxy resins and phenolic resins.

[0131] The amount of flame retardant to be added is appropriately selected depending on the type of phosphorus-based flame retardant, the components of the thermosetting resin composition, and the desired level of flame retardancy. For example, the phosphorus content in the organic components (excluding organic solvents) in the thermosetting resin composition is preferably 0.2 to 4 mass%, more preferably 0.4 to 3.5 mass%, and even more preferably 0.6 to 3 mass%. If the phosphorus content is too low, it may be difficult to ensure flame retardancy, while if it is too high, it may have a negative impact on heat resistance. When a phosphorus-based flame retardant is used, a flame retardant aid such as magnesium hydroxide may be used in combination.

[0132] A filler can be used in the thermosetting resin composition as needed. Specific examples include fused silica, crystalline silica, alumina, silicon nitride, aluminum hydroxide, boehmite, magnesium hydroxide, talc, mica, calcium carbonate, calcium silicate, calcium hydroxide, magnesium carbonate, barium carbonate, barium sulfate, boron nitride, carbon, carbon fiber, glass fiber, alumina fiber, silica-alumina fiber, silicon carbide fiber, polyester fiber, cellulose fiber, aramid fiber, ceramic fiber, fine rubber particles, thermoplastic elastomer, and pigment. A common reason for using a filler is to improve impact resistance. When metal hydroxides such as aluminum hydroxide, boehmite, and magnesium hydroxide are used, they function as flame retardant aids, improving flame retardancy. The amount of these fillers added is preferably 1 to 150% by mass, more preferably 10 to 70% by mass, of the total thermosetting resin composition. Higher amounts may result in reduced adhesion, which is necessary for laminate applications, and may also result in brittle cured products, which may not achieve sufficient mechanical properties. If the blending amount is too small, the effects of blending the filler, such as improving the impact resistance of the cured product, may not be achieved.

[0133] The thermosetting resin composition may further contain various additives, such as a silane coupling agent, an antioxidant, a release agent, an antifoaming agent, an emulsifier, a thixotropic agent, a smoothing agent, a flame retardant, a pigment, etc. The amount of these additives to be added is preferably in the range of 0.01 to 20% by mass relative to the thermosetting resin composition.

[0134] The thermosetting resin composition of the present invention can be obtained by uniformly mixing the above-mentioned components. A thermosetting resin composition containing a thermosetting resin, an epoxy resin, and optionally various other materials can be cured to obtain a cured thermosetting resin product by a method similar to that used for known thermosetting resin compositions. Examples of cured products include molded cured products such as laminates, cast products, molded products, adhesive layers, insulating layers, and films. Methods similar to those used for known thermosetting resin compositions can be used to obtain the cured product. Suitable methods include casting, injection, potting, dipping, drip coating, transfer molding, compression molding, and laminating resin sheets, resin-coated copper foils, prepregs, etc., and curing them under heat and pressure to form laminates.

[0135] The curing method for a thermosetting resin composition varies depending on the components and their amounts in the thermosetting resin composition, but typically involves a curing temperature of 80 to 300°C and a curing time of 10 to 360 minutes. This heating is preferably performed in two stages: a primary heating at 80 to 180°C for 10 to 90 minutes, followed by a secondary heating at 120 to 200°C for 60 to 150 minutes. For formulations in which the glass transition temperature (Tg) exceeds the secondary heating temperature, a tertiary heating at 150 to 280°C for 60 to 120 minutes is also preferred. Such secondary and tertiary heating can reduce curing defects. When preparing semi-cured resin products such as resin sheets, resin-coated copper foils, and prepregs, the curing reaction of the thermosetting resin composition is typically allowed to proceed to a degree that allows the product to maintain its shape by heating or other means. When a thermosetting resin composition contains a solvent, the majority of the solvent is typically removed by techniques such as heating, reduced pressure, and air drying. However, up to 5% by mass of the solvent may remain in the semi-cured resin product. An uncured or partially cured sheet of the thermosetting resin composition of the present invention can be suitably used, for example, as a build-up film, a bonding sheet, a coverlay sheet, a bump sheet for a flip-chip bonder, or an insulating layer or adhesive layer for a substrate.

[0136] The thermosetting resin composition can be used in a variety of fields, including as a circuit board material, sealing material, casting material, conductive paste, adhesive, insulating material, etc., and is particularly useful in the electrical and electronic fields as an insulating casting material, laminate material, sealing material, etc. Examples of applications include printed wiring boards, flexible wiring boards, laminates for electrical and electronic circuits such as capacitors, resin-coated metal foils, adhesives such as film adhesives and liquid adhesives, semiconductor sealing materials, underfill materials, interchip fill materials for 3D-LSI, insulating materials for circuit boards, insulating sheets, prepregs, heat dissipation substrates, and resist inks, but are not limited to these.

[0137] Among these various applications, in applications such as printed wiring board materials, insulating materials for circuit boards, and adhesive films for build-up, they can be used as insulating materials for so-called substrates with built-in electronic components, in which passive components such as capacitors and active components such as IC chips are embedded in the substrate. Among these, due to their properties such as high flame retardancy, high heat resistance, and solvent solubility, they are preferably used as printed wiring board materials, thermosetting resin compositions for flexible wiring boards, materials for circuit boards (laminates) such as interlayer insulating materials for build-up boards, and semiconductor encapsulation materials.

[0138] When the thermosetting resin composition is formed into a plate such as a laminate, the filler to be used is preferably a fibrous one in terms of dimensional stability, bending strength, etc., and more preferably a glass cloth, glass mat, or glass roving cloth.

[0139] The thermosetting resin composition can be impregnated into a fibrous reinforcing substrate to produce a prepreg for use in printed wiring boards, etc. Examples of fibrous reinforcing substrates that can be used include, but are not limited to, inorganic fibers such as glass, and woven or nonwoven fabrics of organic fibers such as polyester resin, polyamine resin, polyacrylic resin, polyimide resin, and aromatic polyamide resin.

[0140] The method for producing a prepreg from a thermosetting resin composition is not particularly limited. For example, the thermosetting resin composition is prepared into a resin varnish by adjusting the viscosity to an appropriate level with an organic solvent. The resin varnish is then impregnated into the fibrous reinforcing substrate, and the resin component is semi-cured (B-staged) by heating and drying. The heating temperature is preferably 50 to 200°C, more preferably 100 to 170°C, depending on the type of organic solvent used. The heating time is adjusted depending on the type of organic solvent used and the curability of the prepreg, and is preferably 1 to 40 minutes, more preferably 3 to 20 minutes. In this case, the mass ratio of the thermosetting resin composition to the reinforcing substrate used is not particularly limited, but it is usually preferable to adjust it so that the resin content in the prepreg is 20 to 80% by mass.

[0141] The thermosetting resin composition of the present invention can be formed into a sheet or film for use. In this case, it can be formed into a sheet or film using a conventionally known method. The method for producing a resin sheet is not particularly limited, but examples include: (1) an extrusion molding method in which a thermosetting resin composition is kneaded in an extruder, extruded, and formed into a sheet using a T-die, circular die, or the like; (2) a casting molding method in which a thermosetting resin composition is dissolved or dispersed in a solvent such as an organic solvent, and then cast to form a sheet; and (3) other conventionally known sheet molding methods. The thickness (μm) of the resin sheet is not particularly limited, but is preferably 10 to 300, more preferably 25 to 200, and even more preferably 40 to 180. When used in a build-up method, the thickness of the resin sheet is particularly preferably 40 to 90 μm. A thickness of 10 μm or more ensures insulation, while a thickness of 300 μm or less prevents the circuit distance between electrodes from becoming unnecessarily long. The solvent content of the resin sheet is not particularly limited, but is preferably 0.01 to 5% by mass relative to the entire thermosetting resin composition. If the solvent content in the film is 0.01% by mass or more relative to the entire thermosetting resin composition, adhesion and bonding are easily obtained when laminating to a circuit board, and if it is 5% by mass or less, flatness after heat curing is easily obtained.

[0142] A more specific method for producing an adhesive sheet is to apply a varnish-like thermosetting resin composition containing the organic solvent onto a supporting base film that is insoluble in organic solvents using a coater such as a reverse roll coater, comma coater, or die coater, and then heat and dry the film to bring the resin component into a B-stage. If necessary, another supporting base film is placed on the coated surface (adhesive layer) as a protective film, and the film is dried to obtain an adhesive sheet having release layers on both sides of the adhesive layer.

[0143] Examples of the supporting base film include metal foils such as copper foil, polyolefin films such as polyethylene film and polypropylene film, polyester films such as polyethylene terephthalate film, polycarbonate film, silicone film, and polyimide film. Among these, polyethylene terephthalate film is preferred because it is free of defects, has excellent dimensional accuracy, and is cost-effective. Metal foils, particularly copper foils, are preferred because they are easy to form into multilayer laminates. The thickness of the supporting base film is not particularly limited, but is preferably 10 to 150 μm, more preferably 25 to 50 μm, because it has the strength to serve as a support and is less likely to cause lamination defects.

[0144] The thickness of the protective film is not particularly limited, but is generally 5 to 50 μm. It is preferable to preliminarily treat the surface with a release agent to facilitate peeling of the molded adhesive sheet. The thickness of the applied resin varnish, after drying, is preferably 5 to 200 μm, more preferably 5 to 100 μm.

[0145] The heating temperature depends on the type of organic solvent used and is preferably 50 to 200° C., more preferably 100 to 170° C. The heating time is adjusted depending on the type of organic solvent used and the curing properties of the prepreg, and is preferably 1 to 40 minutes, more preferably 3 to 20 minutes.

[0146] The resin sheet obtained in this manner usually becomes an insulating adhesive sheet having insulating properties, but a conductive adhesive sheet can also be obtained by mixing conductive metal or metal-coated fine particles into the thermosetting resin composition. The supporting base film is peeled off after laminating it to the circuit board or after heat curing to form the insulating layer. Peeling off the supporting base film after heat curing the adhesive sheet can prevent the adhesion of dust and other particles during the curing process. Here, the insulating adhesive sheet also serves as an insulating sheet.

[0147] When the resin sheet of the present invention is used as a bonding sheet, for example, two substrates can be bonded with the resin sheet. Each of the two substrates is, for example, a laminate or a printed wiring board. Specifically, for example, a resin sheet is produced by forming a multifunctional vinyl resin composition into a sheet on a support film by a coating method or the like, and then heating it to dry or semi-cure it. This resin sheet is then placed on a substrate (first substrate), the support film is peeled off from the resin sheet, and another substrate (second substrate) is placed on top of it. That is, the first substrate, the resin sheet (multifunctional vinyl resin composition), and the second substrate are laminated in this order. Subsequently, the first substrate and the second substrate are bonded together via the cured product of the multifunctional vinyl resin composition by heating and curing.

[0148] The resin-coated metal foil obtained from the thermosetting resin composition of the present invention will now be described. The metal foil can be a single metal, alloy, or composite foil of copper, aluminum, brass, nickel, or the like. A metal foil with a thickness of 9 to 70 μm is preferably used. The method for producing the resin-coated metal foil from the thermosetting resin composition and metal foil of the present invention is not particularly limited. For example, the resin-coated metal foil can be obtained by applying a resin varnish, in which the viscosity of the thermosetting resin composition is adjusted with a solvent, to one side of the metal foil using a roll coater or the like, followed by heating and drying to semi-cure (B-stage) the resin component to form a resin layer. To semi-cure the resin component, for example, heating and drying can be performed at 100 to 200°C for 1 to 40 minutes. The thickness of the resin portion of the resin-coated metal foil is preferably 5 to 110 μm.

[0149] To harden the prepreg or insulating adhesive sheet, a laminate hardening method generally used in the manufacture of printed wiring boards can be used, but is not limited to this. For example, when forming a laminate using prepreg, one or more prepregs are stacked, and metal foil is placed on one or both sides to form a laminate, and this laminate is then pressurized and heated to harden and integrate the prepregs to obtain a laminate. Here, the metal foil can be a single, alloy, or composite metal foil of copper, aluminum, brass, nickel, etc.

[0150] The conditions for heating and pressing the laminate can be appropriately adjusted to cure the thermosetting resin composition. However, if the pressure is too low, air bubbles may remain inside the resulting laminate, resulting in reduced electrical properties. Therefore, it is preferable to pressurize the laminate under conditions that satisfy moldability. The heating temperature is preferably 160 to 250°C, more preferably 170 to 220°C. The pressure is preferably 0.5 to 10 MPa, more preferably 1 to 5 MPa. The heating and pressing time is preferably 10 minutes to 4 hours, more preferably 40 minutes to 3 hours. If the heating temperature is too low, the curing reaction may not proceed sufficiently, while if the pressure is too high, thermal decomposition of the cured product may occur. If the pressure is too low, air bubbles may remain inside the resulting laminate, resulting in reduced electrical properties. If the pressure is too high, the resin may flow before curing, preventing the desired thickness from being obtained. If the heating and pressing time is too short, the curing reaction may not proceed sufficiently, while if it is too long, thermal decomposition of the cured product may occur.

[0151] A multilayer board can be produced using the single-layer laminate thus obtained as an inner layer material. In this case, a circuit is first formed on the laminate by an additive process, subtractive process, or the like, and the circuit surface is then blackened with an acid solution to obtain an inner layer material. An insulating layer is formed on one or both circuit-forming surfaces of this inner layer material using a prepreg, resin sheet, insulating adhesive sheet, or resin-coated metal foil, and a conductor layer is then formed on the surface of the insulating layer to form a multilayer board.

[0152] When forming an insulating layer using prepreg, one or more prepreg sheets are placed on the circuit-forming surface of the inner layer material, and a metal foil is placed on the outer surface to form a laminate. This laminate is heated and pressurized to form an integral molding, whereby the cured prepreg is formed as an insulating layer, and the outer metal foil is formed as a conductor layer. The metal foil can be the same as that used in the laminate used as the inner layer material. The heat and pressure molding can be performed under the same conditions as for molding the inner layer material. The surface of the multilayer laminate thus formed can then be further subjected to via hole formation and circuit formation by an additive or subtractive method to form a printed wiring board. By repeating the above process using this printed wiring board as the inner layer material, further multilayer boards can be formed.

[0153] For example, when forming an insulating layer using an insulating adhesive sheet, a laminate is formed by placing an insulating adhesive sheet on the circuit-forming surfaces of multiple inner layer materials. Alternatively, a laminate is formed by placing an insulating adhesive sheet between the circuit-forming surfaces of the inner layer materials and a metal foil. This laminate is then heated and pressurized to form an integral molding, thereby forming a cured product of the insulating adhesive sheet as an insulating layer and forming a multilayered inner layer material. Alternatively, the cured product of the insulating adhesive sheet is formed as an insulating layer between the inner layer material and the metal foil, which is the conductor layer. Here, the same metal foil as that used in the laminate used as the inner layer material can be used. The heat and pressure molding can be performed under the same conditions as those used to mold the inner layer material.

[0154] When forming an insulating layer by applying a thermosetting resin composition to a laminate, the thermosetting resin composition is preferably applied to a thickness of 5 to 100 μm, and then heated and dried at 100 to 200°C, preferably 150 to 200°C, for 1 to 120 minutes, preferably 30 to 90 minutes, to form a sheet. This is generally formed by a method known as the casting method. The thickness after drying is preferably 5 to 150 μm, preferably 5 to 80 μm. The viscosity of the thermosetting resin composition is preferably 10 to 40,000 mPa·s at 25°C, and more preferably 200 to 30,000 mPa·s, because this ensures a sufficient film thickness and reduces the occurrence of uneven coating or streaks. A printed wiring board can be formed by further forming via holes and circuits on the surface of the multilayer laminate formed in this manner using an additive or subtractive method. Further multilayer laminates can be formed by repeating the above process using this printed wiring board as an inner layer material.

[0155] The thermosetting resin composition of the present invention can be used as a sealing material for tape-shaped semiconductor chips, potting-type liquid sealing, underfill, semiconductor interlayer insulating film, etc. For example, semiconductor package molding can be performed by molding the thermosetting resin composition using a casting machine, a transfer molding machine, an injection molding machine, or the like, and then heating the molded product at 50 to 200°C for 2 to 10 hours.

[0156] In order to prepare a thermosetting resin composition for use as a semiconductor encapsulating material, a method can be used in which the thermosetting resin composition is premixed with compounding agents such as an inorganic filler, and additives such as a coupling agent and a mold release agent, which are to be compounded as needed, and then the mixture is melt-mixed thoroughly until homogeneous using an extruder, kneader, roll, etc. In this case, silica is usually used as the inorganic filler, and in this case, the inorganic filler is preferably compounded in a proportion of 70 to 95 mass % in the thermosetting resin composition.

[0157] When the thermosetting resin composition thus obtained is used as a tape-shaped sealing material, it can be heated to prepare a semi-cured sheet to form a sealing tape, and then this sealing tape can be placed on a semiconductor chip, heated to 100 to 150° C. to soften and mold, and then completely cured at 170 to 250° C. When used as a potting-type liquid sealing material, the obtained thermosetting resin composition can be dissolved in a solvent as needed, applied to a semiconductor chip or an electronic component, and directly cured.

[0158] The thermosetting resin composition of the present invention can also be used as a resist ink. In this case, a vinyl monomer having an ethylenically unsaturated double bond and a cationic polymerization catalyst as a curing agent are blended with the thermosetting resin composition, and a pigment, talc, and a filler are further added to form a resist ink composition, which is then applied to a printed circuit board by screen printing to form a cured resist ink. The curing temperature in this case is preferably in the range of about 20 to 250°C.

[0159] A thermosetting resin composition was prepared, and the laminate and cured product were evaluated after heat curing. As a result, it was found that the cured product exhibited excellent low dielectric properties, and furthermore, a thermosetting resin composition with excellent heat resistance suitable for printed wiring board applications was provided.

[0160] The present invention will be specifically described with reference to examples and comparative examples, but the present invention is not limited thereto. Unless otherwise specified, "parts" means parts by mass, "%" means % by mass, and "ppm" means ppm by mass. Each physical property was measured by the following method.

[0161] (1) Hydroxyl group equivalent: Measured in accordance with JIS K0070, and expressed in units of g / eq. Unless otherwise specified, the hydroxyl group equivalent of an aromatic polyhydroxy compound means the phenolic hydroxyl group equivalent.

[0162] (2) Softening point: Measured in accordance with the ring and ball method of JIS K7234. Specifically, an automatic softening point analyzer (ASP-MG4, manufactured by Meitec Corporation) was used.

[0163] (3) Dielectric Constant and Dielectric Loss Tangent: The dielectric constant and dielectric loss tangent were evaluated by determining them at a frequency of 1 GHz by the capacitance method using a material analyzer (manufactured by AGILENT Technologies) in accordance with IPC-TM-650 2.5.5.9.

[0164] (4) Glass transition temperature (Tg): In accordance with IPC-TM-650 2.4.25.c, the glass transition temperature (Tg) was expressed as the DSC Tgm (the intermediate temperature on the displacement curve with respect to the tangent line between the glassy state and the rubbery state) when measured using a differential scanning calorimeter (EXSTAR6000 DSC6200, manufactured by Hitachi High-Tech Science Corporation) at a temperature rise rate of 20°C / min.

[0165] (5) GPC (Gel Permeation Chromatography) Measurement: A column (TSKgel G4000H, manufactured by Tosoh Corporation) was attached to the main body (HLC-8220GPC, manufactured by Tosoh Corporation). ＸＬ ,TSKgelG3000H ＸＬ ,TSKgelG2000H ＸＬ ) in series was used, and the column temperature was 40°C. Tetrahydrofuran (THF) was used as the eluent, with a flow rate of 1 mL / min, and a differential refractive index detector was used as the detector. 0.1 g of sample was dissolved in 10 mL of THF and filtered through a microfilter, and 50 μL of the sample was used for measurement. Mw and Mn were calculated from a calibration curve obtained from standard polystyrene (PStQuick Kit-H, manufactured by Tosoh Corporation). Data processing was performed using GPC-8020 Model II Version 6.00 manufactured by Tosoh Corporation.

[0166] (6) IR: Fourier transform infrared spectrophotometer (Spectrum One FT-IR Spectrometer 1760X, manufactured by Perkin Elmer Precisly) was used, and diamond ATR was used, and the wave number was 650 to 4000 cm －１ The absorbance was measured.

[0167] The abbreviations used in the examples and comparative examples are as follows: [Aromatic hydroxy compounds] PH1: Aromatic hydroxy compound obtained in Synthesis Example 1 PH2: Aromatic hydroxy compound obtained in Synthesis Example 2 PH3: 1-naphthol PH4: Biphenylaralkyl polyhydric hydroxy resin (MEH-7851, manufactured by Meiwa Kasei Co., Ltd., phenolic hydroxyl group equivalent weight 223)

[0168] [Aromatic carboxylic acid halides] B1: isophthalic acid chloride B2: terephthalic acid chloride

[0169] [Unsaturated group-containing carboxylic acid anhydrides and unsaturated group-containing carboxylic acid halides] C1: methacrylic acid anhydride C2: methacrylic acid chloride

[0170] [Epoxy Resin] E1: Phenol-dicyclopentadiene type epoxy resin (KDCP-130, manufactured by Kokuto Chemical Co., Ltd., epoxy equivalent 254, softening point 72°C)

[0171] [Thermosetting ester resins] A1: Thermosetting ester resin obtained in Example 1 A2: Thermosetting ester resin obtained in Example 2 A3: Thermosetting ester resin obtained in Example 3 A4: Thermosetting ester resin obtained in Example 4 A5: Thermosetting ester resin obtained in Example 5 A6: Thermosetting ester resin obtained in Example 6 A7: Thermosetting ester resin obtained in Example 7 A8: Thermosetting ester resin obtained in Example 8 A9: Thermosetting ester resin obtained in Example 9 A10: Thermosetting ester resin obtained in Reference Example 1 A11: Thermosetting ester resin obtained in Reference Example 2 [Vinyl group-containing resins] VH1: Multifunctional vinyl resin (manufactured by Mitsubishi Gas Chemical Company, Inc., vinylbenzyl ether-terminated PPE resin, OPE-2ST, Mn1187) VH2: Multifunctional vinyl resin (manufactured by SABIC Japan, LLC, methacrylic-terminated PPE resin, SA9000, Mw1600)

[0172] [Curing accelerator] PO: organic peroxide (manufactured by NOF Corporation, Perbutyl P) C1: 4-dimethylaminopyridine (manufactured by Kishida Chemical Co., Ltd.)

[0173] [Others] AO: Antioxidant (ADEKA CORPORATION, Adekastab AO-60)

[0174] Synthesis Example 1 2,6-xylenol (structural formula below) was added to a reaction apparatus consisting of a separable glass flask equipped with a stirrer, a thermometer, a nitrogen inlet tube, a dropping funnel, and a condenser. 500 copies, 47% BF ３ 7.3 parts of an ether complex was added and heated to 100°C with stirring. While maintaining the temperature, dicyclopentadiene (structural formula below) To the mixture, 67.6 parts (0.12 times the moles of 2,6-xylenol) of 2,6-xylenol was added dropwise over 1 hour. The mixture was further reacted at 115-125°C for 4 hours, and then 11 parts of calcium hydroxide was added. 19 parts of a 10% aqueous oxalic acid solution were then added. The mixture was then heated to 160°C for dehydration, and then heated to 200°C under a reduced pressure of 5 mmHg to remove unreacted raw materials by evaporation. 1,320 parts of methyl isobutyl ketone (MIBK) were added to dissolve the product, and 400 parts of 80°C hot water was added for water washing, and the lower layer of water was separated and removed. The mixture was then heated to 160°C under a reduced pressure of 5 mmHg to remove the MIBK by evaporation, yielding 164 parts of a reddish-brown aromatic hydroxy compound (PH1). The resulting aromatic hydroxy compound (PH1) had a hydroxyl equivalent of 195 and a softening point of 73°C. The aromatic hydroxy compound represented by formula (8): R1 was a methyl group, i was 2, and as measured by GPC, Mw was 470, Mn was 440, the content of u=0 isomer was 2.8 area%, the content of u=1 isomer was 86.2 area%, and the content of u=2 or more isomers was 11.0 area%.

[0175] Synthesis Example 2: Into the same reaction apparatus as in Synthesis Example 1, 400 parts of phenol, 47% BF ３7.5 parts of an ether complex was charged and heated to 70°C with stirring. While maintaining the same temperature, 70.2 parts of dicyclopentadiene was added dropwise over 2 hours. The reaction was continued for another 4 hours at 125-135°C, and 11.7 parts of calcium hydroxide was added. 20 parts of a 10% aqueous oxalic acid solution were then added. The mixture was then heated to 160°C for dehydration, and then heated to 200°C under a reduced pressure of 5 mmHg to remove unreacted raw materials by evaporation. 1100 parts of MIBK was added to dissolve the product, and 330 parts of 80°C hot water was added for water washing, and the lower layer of water was separated and removed. The mixture was then heated to 160°C under a reduced pressure of 5 mmHg to remove the MIBK by evaporation, yielding 158 parts of a reddish-brown aromatic hydroxy compound (PH2). The resulting aromatic hydroxy compound (PH2) had a hydroxyl equivalent of 177 and a softening point of 92°C. The aromatic hydroxy compound was represented by formula (11), in which i was 0, and the Mw was 460 and Mn was 394 as measured by GPC. The content of m=0 isomer was 0 area %, the content of m=1 isomer was 66.7 area %, and the content of m=2 or more isomers was 33.3 area %.

[0176] Example 1 A reaction apparatus equipped with a stirrer, a thermometer, a nitrogen inlet, a dropping funnel, and a condenser was charged with 100 parts of the reactive group-containing aromatic hydroxy compound (PH1) obtained in Synthesis Example 1, 1.7 parts of tetra-n-butylammonium bromide (TBAB), 20.8 parts of isophthalic acid chloride (B1) as an aromatic carboxylic acid halide (0.20 equivalents relative to the hydroxyl group equivalent of PH1), 400 parts of PH1 and toluene (TL) were added and heated to 50°C to dissolve them. While controlling the temperature in the system to 20°C or less, 56.9 parts of methacrylic anhydride (MA: structural formula below) (0.72 equivalents relative to the hydroxyl group equivalent of PH1) were added. To the mixture, 106.7 parts of a 25% aqueous sodium hydroxide solution (25% NaOH) was added dropwise over 3 hours, and stirring was then continued at the same temperature for another 4 hours. The reaction mixture was allowed to stand for liquid separation, and the water bath was removed. This procedure was repeated until the pH of the water bath reached 7. Water was then removed by reflux dehydration, yielding 213 parts of thermosetting ester resin (A1) in the form of a toluene solution with a nonvolatile content of 60%. The active ester equivalent of the obtained thermosetting ester resin (A1), calculated from the amounts of raw materials charged, was 660. The reactive groups in all of the Y in general formula (1) accounted for 60 mol%. GPC and FT-IR spectra of the obtained thermosetting ester resin (A1) are shown in Figure 1 and Figure 2, respectively.

[0177] Example 2 A reaction apparatus equipped with a stirrer, a thermometer, a nitrogen inlet, a dropping funnel, and a condenser was charged with 100 parts of the aromatic hydroxy compound (PH1) obtained in Synthesis Example 1, 1.7 parts of tetra-n-butylammonium bromide (TBAB), 10.4 parts of isophthalic acid chloride (B1) as an aromatic carboxylic acid halide (0.10 equivalents relative to the hydroxyl group equivalent of PH1), 400 parts of PH1 and toluene (TL) were added, and the temperature was raised to 50°C to dissolve the mixture. While controlling the temperature in the system to 20°C or less, 51.5 parts of methacrylic acid chloride (MC: structural formula below) (0.96 equivalents relative to the hydroxyl group equivalent of PH1) were added. To the mixture, 106.7 parts of a 25% aqueous sodium hydroxide solution (25% NaOH) was added dropwise over 3 hours, and then stirring was continued for another 4 hours at the same temperature. The reaction mixture was allowed to stand for liquid separation, and the water bath was removed. This operation was repeated until the pH of the water bath reached 7. Water was then removed by reflux dehydration, yielding 214 parts of a thermosetting ester resin (A2) in the form of a toluene solution with a nonvolatile content of 60%. The active ester equivalent of the obtained thermosetting ester resin (A2), calculated from the amounts of raw materials charged, was 1,320. The reactive groups in all of Y in general formula (1) accounted for 80 mol%.

[0178] Example 3 The same procedure as in Example 2 was carried out, except that the amount of isophthalic acid chloride (B1) was changed to 20.8 parts and the amount of methacrylic acid chloride was changed to 38.6 parts, to obtain 213 parts of a thermosetting ester resin (A3). The active ester equivalent of the obtained resin (A3), calculated from the amounts of the raw materials charged, was 660. The proportion of reactive groups in all Xs in general formula (1) was 60 mol %.

[0179] Example 4 The same procedure as in Example 2 was carried out, except that the amount of isophthalic acid chloride (B1) was changed to 26.0 parts and the amount of methacrylic acid chloride was changed to 32.2 parts, to obtain 212 parts of a thermosetting ester resin (A4). The active ester equivalent of the obtained resin (A4), calculated from the amounts of the raw materials charged, was 530. The proportion of reactive groups in all Xs in general formula (1) was 50 mol %.

[0180] Example 5: The same procedure as in Example 2 was carried out, except that 20.8 parts of terephthalic acid chloride (B2) and 38.6 parts of methacrylic acid chloride were used instead of isophthalic acid chloride (B1), to obtain 213 parts of a thermosetting ester resin (A5). The active ester equivalent of the obtained resin (A5), calculated from the amounts of the raw materials charged, was 660. The proportion of reactive groups in all Xs in general formula (1) was 60 mol%.

[0181] Example 6 The same procedure as in Example 2 was carried out, except that 7.4 parts of 1-naphthol (PH3) was added per 100 parts of the aromatic hydroxy compound (PH1), and the amounts of tetra n-butylammonium bromide (TBAB) were changed to 1.8 parts, isophthalic acid chloride (B1) to 22.9 parts, methacrylic acid chloride to 42.5 parts, and toluene to 430 parts, to obtain 231 parts of a thermosetting ester resin (A6). The active ester equivalent of the obtained resin (A6), calculated from the amounts of the raw materials charged, was 650. The proportion of reactive groups in all Xs in general formula (1) was 60 mol%.

[0182] Example 7 The same procedure as in Example 2 was carried out, except that 14.8 parts of 1-naphthol (PH3) was added per 100 parts of the aromatic hydroxy compound (PH1), and the amounts of tetra n-butylammonium bromide (TBAB), isophthalic acid chloride (B1), 25.0 parts, methacrylic acid chloride, and 46.3 parts and toluene were changed to 460 parts, to obtain 248 parts of a thermosetting ester resin (A7). The active ester equivalent of the obtained resin (A7), calculated from the amounts of the raw materials charged, was 640. The proportion of reactive groups in all Xs in general formula (1) was 60 mol%.

[0183] Example 8 100 parts of aromatic hydroxy compound (PH2) was added to 100 parts of aromatic hydroxy compound (PH1), and the same procedure as in Example 2 was carried out except that the amounts of tetra-n-butylammonium bromide (TBAB), isophthalic acid chloride (B1) and methacrylic acid chloride were changed to 3.5 parts (0.20 equivalents relative to the hydroxyl group equivalents of PH1 and PH2), 43.8 parts (0.72 equivalents relative to the hydroxyl group equivalents of PH1 and PH2), and 800 parts of toluene were changed to 432 parts. The active ester equivalent of the resulting resin (A8) calculated from the amounts of raw materials charged was 630. The reactive groups in all X in general formula (1) were 60 mol%.

[0184] Example 9 100 parts of aromatic hydroxy compound (PH4) was added to 100 parts of aromatic hydroxy compound (PH1), and the same operations as in Example 2 were carried out except that the amounts of tetra-n-butylammonium bromide (TBAB) and isophthalic acid chloride (B1) were changed to 3.1 parts (0.20 equivalents relative to the hydroxyl group equivalents of PH1 and PH2), and methacrylic acid chloride were changed to 72.3 parts (0.72 equivalents relative to the hydroxyl group equivalents of PH1 and PH2), and toluene was changed to 800 parts. 420 parts of thermosetting ester resin (A9) were obtained. The active ester equivalent of the obtained resin (A9) calculated from the amount of raw materials charged was 690. The reactive groups in all X in general formula (1) were 60 mol%.

[0185] Reference Example 1 The same operation as in Example 1 was carried out, except that the aromatic hydroxy compound (PH1) was 100 parts, 1-naphthol (PH3) was 24.4 parts, tetra n-butylammonium bromide (TBAB) was 1.9 parts, isophthalic acid chloride (B1) was 69.2 parts, 20% aqueous sodium hydroxide solution (20% NaOH) was 136 parts, and toluene (TL) was 480 parts, and methacrylic acid anhydride was not added. A thermosetting ester resin (A10) was obtained. Note that, since methacrylic acid anhydride was not added, the reaction proceeds even in a low-concentration aqueous NaOH solution. For the obtained resin (A10), the active ester equivalent calculated from the amount of raw materials charged was 248.

[0186] Reference Example 2 The aromatic hydroxy compound (PH2) was 100 parts, 1-naphthol (PH3) was 26.9 parts, tetra n-butylammonium bromide (TBAB) was 2.1 parts, isophthalic acid chloride (B1) was 76.3 parts, 20% aqueous sodium hydroxide solution (20% NaOH) was 150 parts, and toluene (TL) was 510 parts, but methacrylic acid anhydride was not added. The same operation as in Example 1 was carried out to obtain a thermosetting ester resin (A11). Since methacrylic acid anhydride was not added, the reaction proceeded even with a low-concentration NaOH aqueous solution. For the obtained resin (A11), the active ester equivalent calculated from the amount of raw materials charged was 235.

[0187] The raw material blending ratios and physical properties of Examples 1 to 9 and Reference Examples 1 and 2 are summarized in Table 1.

[0188] Example 10: 100 parts of the thermosetting ester resin (A1) obtained in Example 1, 100 parts of the vinyl resin (E), and 1.0 part of PO as a curing accelerator were blended in solids equivalent, and dissolved in toluene to a nonvolatile content of 50% to obtain a thermosetting resin composition varnish. The obtained thermosetting resin composition varnish was impregnated into glass cloth (manufactured by Nitto Boseki Co., Ltd., WEA 7628 XS13, 0.18 mm thick). The impregnated glass cloth was dried in a hot air circulating oven at 150°C for 5 minutes to obtain a prepreg.

[0189] The resulting prepreg was loosened and sieved to obtain prepreg powder (100 mesh pass). The resulting prepreg powder was placed in a fluororesin mold and vacuum pressed at 2 MPa under the following temperature conditions: 130°C for 15 minutes and 210°C for 80 minutes, yielding test pieces measuring 50 mm square and 2 mm thick. The dielectric constant and dielectric loss tangent of the test pieces are shown in Table 2.

[0190] Examples 11 to 19 and Comparative Examples 1 to 6: Prepregs and test pieces were obtained by compounding the amounts (parts) shown in Table 1 and carrying out the same operations as in Example 10. The results of the relative permittivity and dielectric loss tangent of the obtained test pieces are shown in Table 2. The compounding amounts of A1 to A11, etc., are shown as solid content converted values.

[0191]

[0192] The thermosetting ester resin and resin composition of the present invention are applicable to various fields such as paints, civil engineering adhesives, casting, electric and electronic materials, film materials, etc. They are particularly useful for printed wiring boards, which are one type of electric and electronic material.

Claims

1. A thermosetting resin comprising polyaryloxy units and polyarylcarbonyl units, characterized in that the polyaryloxy units contain reactive group-containing units represented by the following formula (1): Here, R1 independently represents a hydrocarbon group having 1 to 8 carbon atoms, R2 independently represents a hydrogen atom or a hydrocarbon group having 1 to 12 carbon atoms, Y independently represents a bonding site with a polyarylcarbonyl unit or a reactive group represented by formula (2), and 1 to 99 mol % of all Y's are reactive groups represented by formula (2), R represents a hydrogen atom or an alkyl or alkenyl group having 1 to 8 carbon atoms, i is an integer from 0 to 2, and n represents the number of repetitions, the average of which is a number from 0 to 5.

2. A thermosetting ester resin according to claim 1, which contains polyaryloxy units other than the unit represented by the above formula (1) as the polyaryloxy units, and the other polyaryloxy units are units represented by the following formula (3) and / or formula (4). Here, Ar1 is independently an aromatic ring group of any one of a benzene ring, a naphthalene ring, a furan ring, and a biphenyl ring, and these aromatic rings may have an alkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, an aryl group having 6 to 11 carbon atoms, an aralkyl group having 7 to 12 carbon atoms, an aryloxy group having 6 to 11 carbon atoms, or an aralkyloxy group having 7 to 12 carbon atoms as a substituent. Ar11 is a divalent hydrocarbon group having 1 to 10 carbon atoms or a divalent group represented by formula (3a). R11 is independently a hydrogen atom or a hydrocarbon group having 1 to 8 carbon atoms. R3 is a direct bond or a hydrocarbon group having 1 to 20 carbon atoms, -CO-, -O-, -S-, -SO ２ -, and -C(CF ３ ) ２ - is a divalent group selected from the group consisting of. m represents the number of repetitions, the average value of which is a number from 1 to 5. r is 1 or 2. k is 0 or 1.

3. The thermosetting ester resin according to claim 1, further comprising a monoaryloxy unit, the monoaryloxy unit being a group represented by the following formula (6): Here, Ar2 is independently an aromatic ring group of a benzene ring, a naphthalene ring, a furan ring, or a biphenyl ring, and these aromatic rings may have, as a substituent, an alkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, an aryl group having 6 to 11 carbon atoms, an aralkyl group having 7 to 12 carbon atoms, an aryloxy group having 6 to 11 carbon atoms, or an aralkyloxy group having 7 to 12 carbon atoms. R4 is a direct bond, -CH ２ -, -C(CH ３ ) ２ -, -CH(CH ３ )-, -CO-, -O-, -S-, -SO ２ -, and -C(CF ３ ) ２ - is a divalent group selected from the group consisting of a direct bond, -CH ２ -, -C(CH ３ ) ２ -, -CH(CH ３ )-, and -C(CF ３ ) ２ - is a divalent group selected from the group consisting of -, and k is 0 or 1.

4. The thermosetting ester resin according to claim 1, wherein the polyarylcarbonyl unit is a unit represented by the following formula (7): Here, Ar3 is independently an aromatic ring group of any one of a benzene ring, a naphthalene ring, a furan ring, and a biphenyl ring, and these aromatic rings may have, as a substituent, an alkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, an aryl group having 6 to 11 carbon atoms, an aralkyl group having 7 to 12 carbon atoms, an aryloxy group having 6 to 11 carbon atoms, or an aralkyloxy group having 7 to 12 carbon atoms. R5 is a direct bond, a hydrocarbon group having 1 to 20 carbon atoms, -CO-, -O-, -S-, -SO ２ -, and -C(CF ３ ) ２ - is a divalent group selected from the group consisting of 0 and 1.

5. A method for producing the thermosetting ester resin of claim 1, comprising using as raw materials an aromatic polyhydric hydroxy compound (A1) containing a polyhydric hydroxy compound represented by the following formula (11), an unsaturated group-containing carboxylic anhydride (B1) represented by the following formula (12a) or an unsaturated group-containing carboxylic acid halide (B2) represented by the following formula (12b), and an aromatic polyhydric carboxylic acid (C1) represented by the following formula (17a) or an aromatic polyhydric carboxylic acid halide (C2) represented by the following formula (17b). Here, R1, R2, i, and n are each defined as in formula (1) above. Here, R is defined as in the above formula (2), and X represents a halogen. Here, Ar3, R5, and k are each defined as in the above formula (7), and X represents a halogen.

6. A method for producing a thermosetting ester resin according to claim 5, in which the total of the unsaturated group-containing carboxylic acid anhydride or acid halide and the aromatic polycarboxylic acid or its acid halide is reacted in an amount of 0.1 to 2.0 equivalents per equivalent of the phenolic hydroxyl group of the aromatic polyhydric hydroxy compound.

7. A method for producing a thermosetting ester resin according to claim 5, further comprising an aromatic monohydroxy compound (A2), the aromatic monohydroxy compound (A2) being a compound represented by the following formula (16): Here, Ar2, R4, R14, and k are each defined as in formula (6) above.

8. A thermosetting resin composition comprising, as an essential component, the thermosetting ester resin according to any one of claims 1 to 4.

9. A cured product obtained by curing the thermosetting resin composition according to claim 8.

10. A prepreg comprising the thermosetting resin composition or a semi-cured product thereof according to claim 8 and a fibrous base material.

11. A resin sheet comprising a resin layer of the thermosetting resin composition or a semi-cured product thereof according to claim 8, and a support film.

12. A laminate comprising the prepreg according to claim 10.

13. A laminate comprising the resin sheet according to claim 11.

14. A material for circuit boards, comprising the thermosetting resin composition according to claim 8.

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