TWI883161B - Resin composition - Google Patents

Abstract

The subject of the present invention is to provide a resin composition that can obtain a hardened material with a low dielectric tangent and a high glass transition temperature. The solution of the present invention is a resin composition comprising (A) a maleimide compound, (B) an epoxy resin and (C) an active ester hardener, wherein (A) the maleimide compound comprises (A-1) a maleimide compound containing a trimethylindane skeleton.

Description

Resin composition

The present invention relates to a resin composition, and further relates to a cured product of the resin composition, and a resin sheet, a printed wiring board and a semiconductor device obtained by using the resin composition.

As a manufacturing technology for printed wiring boards, a manufacturing method using a build-up method in which insulating layers and conductive layers are alternately stacked is known. In the manufacturing method using the build-up method, generally speaking, the insulating layer is formed by hardening a resin composition. As such a resin composition, for example, the resin composition disclosed in Patent Document 1 is known. [Prior Technical Document] [Patent Document]

[Patent Document 1] Japanese Patent Application Publication No. 2020-29494

[The problem that the invention is trying to solve]

The cured product formed by curing the resin composition is used as an insulating layer of a printed wiring board of a semiconductor device. Therefore, it is required to reduce the dielectric tangent of the cured product. In addition, from the perspective of improving heat resistance, it is desired that the glass transition temperature of the cured product is high.

The present invention was created in view of the above-mentioned problem, and its purpose is to provide: a resin composition capable of obtaining a cured product having a low dielectric tangent and a high glass transition temperature; a cured product of the above-mentioned resin composition; a resin sheet having a resin composition layer including the above-mentioned resin composition; a printed wiring board including an insulating layer formed by the cured product of the above-mentioned resin composition; and a semiconductor device including the above-mentioned printed wiring board. [Means for Solving the Problem]

The inventors of the present invention have made intensive research to solve the aforementioned problems, and have found that a resin composition comprising (A) a maleimide compound, (B) an epoxy resin, and (C) an active ester hardener, wherein (A) the maleimide compound comprises (A-1) a maleimide compound containing a trimethylindane skeleton, can solve the aforementioned problems, and thus complete the present invention. That is, the present invention includes the following.

[1] A resin composition comprising (A) a maleimide compound, (B) an epoxy resin and (C) an active ester hardener, wherein the (A) maleimide compound comprises (A-1) a maleimide compound having a trimethylindane skeleton. [2] The resin composition as described in [1], wherein the component (A-1) comprises a structure represented by the following formula (A4); (In formula (A4), Ar ^a1 represents a divalent aromatic alkyl group which may have a substituent; R ^a1 each independently represents an alkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, an alkylthio group having 1 to 10 carbon atoms, an aryl group having 6 to 10 carbon atoms, an aryloxy group having 6 to 10 carbon atoms, an arylthio group having 6 to 10 carbon atoms, a cycloalkyl group having 3 to 10 carbon atoms, a halogen atom, a nitro group, a hydroxyl group or a hydroxyl group; R ^a2 each independently represents an alkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, an alkylthio group having 1 to 10 carbon atoms, an aryl group having 6 to 10 carbon atoms, an aryloxy group having 6 to 10 carbon atoms, an arylthio group having 6 to 10 carbon atoms, a cycloalkyl group having 3 to 10 carbon atoms, a halogen atom, a hydroxyl group or a hydroxyl group; R ^a3 each independently represents a divalent aliphatic alkyl group; n _a1 represents a positive integer; n _a2 each independently represents an integer from 0 to 4; n _a3 each independently represents an integer from 0 to 3; the hydrogen atom of the alkyl, alkoxy, alkylthio, aryl, aryloxy, arylthio and cycloalkyl group of R ^a1 may be substituted by a halogen atom; the hydrogen atom of the alkyl, alkoxy, alkylthio, aryl, aryloxy, arylthio and cycloalkyl group of R ^a2 may be substituted by a halogen atom; when n _a2 is 2 to 4, R ^a1 may be the same or different in the same ring; when n _a3 is 2 to 3, R ^a2 may be the same or different in the same ring). [3] The resin composition as described in [1] or [2], wherein the amount of component (A-1) is from 0.5 mass% to 70 mass% relative to 100 mass% of the resin components in the resin composition. [4] The resin composition as described in any one of [1] to [3], wherein the amount of component (A) is from 0.5 mass% to 70 mass% relative to 100 mass% of the resin components in the resin composition. [5] The resin composition as described in any one of [1] to [4], wherein the amount of component (B) is from 3 mass% to 50 mass% relative to 100 mass% of the resin components in the resin composition. [6] The resin composition as described in any one of [1] to [5], wherein the amount of component (C) is 6% by mass or more and 80% by mass or less relative to 100% by mass of the resin component in the resin composition. [7] The resin composition as described in any one of [1] to [6], further comprising (D) an inorganic filler. [8] The resin composition as described in [7], wherein the amount of component (D) is 20% by mass or more and 90% by mass or less relative to 100% by mass of the non-volatile components in the resin composition. [9] The resin composition as described in any one of [1] to [8], which is used for forming an insulating layer. [10] A cured product of the resin composition as described in any one of [1] to [9]. [11] A resin sheet comprising a support and a resin composition layer formed on the support using the resin composition described in any one of [1] to [9]. [12] A printed wiring board comprising an insulating layer formed using a cured product of the resin composition described in any one of [1] to [9]. [13] A semiconductor device comprising the printed wiring board described in [12]. [Effect of the Invention]

According to the present invention, there can be provided: a resin composition capable of obtaining a cured product having a low dielectric tangent and a high glass transition temperature; a cured product of the resin composition; a resin sheet having a resin composition layer including the resin composition; a printed wiring board including an insulating layer formed with the cured product of the resin composition; and a semiconductor device including the printed wiring board.

[Form of implementing the invention]

The present invention is described below by showing embodiments and examples. However, the present invention is not limited to the embodiments and examples shown below, and can be implemented with any modifications within the scope of the invention application and its equivalents.

[1. Overview of resin composition] The resin composition of one embodiment of the present invention comprises (A) a maleimide compound, (B) an epoxy resin and (C) an active ester curing agent. Furthermore, the (A) maleimide compound comprises (A-1) a maleimide compound containing a trimethylindane skeleton.

By using such a resin composition, a hardened material having a low dielectric tangent and a high glass transition temperature can be obtained. Moreover, the hardened material of the aforementioned resin composition can generally reduce the dielectric constant. Furthermore, when the hardened material of the aforementioned resin composition is used to form an insulating layer, the surface roughness of the insulating layer can generally be reduced, thereby improving the plating peel strength.

The resin composition may further contain optional components such as (D) an inorganic filler, (E) an optional hardener, and (F) a hardening accelerator as needed.

[2. (A) Maleimide compound] The maleimide compound as the (A) component contained in the resin composition refers to a compound containing one or more maleimide groups in the molecule. The maleimide group is represented by the following formula (A2). In formula (A2), * represents a bond. The number of maleimide groups contained in one molecule of the (A) maleimide compound is usually 1 or more, preferably 2 or more. There is no particular upper limit, and it can be, for example, 22 or less, 10 or less, 6 or less, 4 or less, or 3 or less.

The (A) maleimide compound contained in the resin composition of the present embodiment includes (A-1) a maleimide compound containing a trimethylindane skeleton. In the following description, the "maleimide compound containing a trimethylindane skeleton" is also referred to as a "specific maleimide compound". The trimethylindane skeleton represents a skeleton represented by the following formula (A3).

Substituents may be bonded to the benzene ring contained in the trimethylindane skeleton. Examples of substituents include alkyl, alkoxy, alkylthio, aryl, aryloxy, arylthio, cycloalkyl, halogen atom, hydroxyl and alkyl. The number of carbon atoms in the alkyl group is preferably 1 to 10. Examples of alkyl groups include methyl, ethyl, propyl, n-butyl, tert-butyl and the like. The number of carbon atoms in the alkoxy group is preferably 1 to 10. Examples of alkoxy groups include methoxy, ethoxy, propoxy, butoxy and the like. The number of carbon atoms in the alkylthio group is preferably 1 to 10. Examples of alkylthio groups include methylthio, ethylthio, propylthio, butylthio and the like. The number of carbon atoms in the aryl group is preferably 6 to 10. Examples of the aryl group include phenyl and naphthyl. The number of carbon atoms of the aryloxy group is preferably 6 to 10. Examples of the aryloxy group include phenoxy and naphthyl. The number of carbon atoms of the arylthio group is preferably 6 to 10. Examples of the arylthio group include phenylthio and naphthylthio. The number of carbon atoms of the cycloalkyl group is preferably 3 to 10. Examples of the cycloalkyl group include cyclopentyl, cyclohexyl, and cycloheptyl. The halogen atom includes fluorine, chlorine, and iodine.

Among the above-mentioned substituents, the hydrogen atom of the alkyl group, alkoxy group, alkylthio group, aryl group, aryloxy group, arylthio group and cycloalkyl group may be substituted with a halogen atom.

The number of substituents bonded to one benzene ring contained in the trimethylindane skeleton may be 1 or 2 or more. The number of substituents bonded to the benzene ring contained in the trimethylindane skeleton is usually 0 or more and 3 or less. When the number of substituents is 2 or more, the 2 or more substituents may be the same or different. It is preferred that no substituent is bonded to the benzene ring contained in the trimethylindane skeleton.

The number of trimethylindane skeletons contained in one molecule of the specific maleimide compound (A-1) may be 1 or 2 or more. The upper limit may be, for example, 10 or less, 8 or less, 7 or less, or 6 or less.

(A-1) The specific maleimide compound preferably contains an aromatic ring skeleton in addition to the above-mentioned trimethylindane skeleton. The number of ring-constituting carbon atoms of the aromatic ring skeleton is preferably 6 to 10. Examples of the aromatic ring skeleton include a benzene ring skeleton and a naphthalene ring skeleton. The number of the above-mentioned aromatic ring skeletons contained in one molecule of the (A-1) specific maleimide compound is preferably 1 or more, more preferably 2 or more, and preferably 6 or less, more preferably 4 or less, and particularly preferably 3 or less. When the (A-1) specific maleimide compound contains 2 or more aromatic ring skeletons in addition to the trimethylindane skeleton, those aromatic ring skeletons may be the same or different.

A substituent may be bonded to the aromatic ring contained in the aforementioned aromatic ring skeleton. As the substituent, for example, the above-mentioned substituents that can be bonded to the benzene ring contained in the trimethylindane skeleton and a nitro group can be cited. The number of substituents bonded to one aromatic ring may be 1 or 2 or more. The number of substituents bonded to the aromatic ring is usually 0 or more and 4 or less. When the number of substituents is 2 or more, the 2 or more substituents may be the same or different.

The (A-1) specific maleimide compound preferably contains a divalent aliphatic alkyl group in addition to the above-mentioned trimethylindane skeleton. In particular, when the (A-1) specific maleimide compound contains an aromatic ring skeleton other than the benzene ring contained in the trimethylindane skeleton, the (A-1) specific maleimide compound preferably contains a divalent aliphatic alkyl group. In this case, the divalent aliphatic alkyl group preferably connects the benzene ring contained in the trimethylindane skeleton and the aromatic ring skeleton. Furthermore, the divalent aliphatic alkyl group preferably connects the aromatic ring skeletons.

The number of carbon atoms in the divalent aliphatic alkyl group is preferably 1 or more, more preferably 12 or less, particularly preferably 8 or less, and particularly preferably 5 or less. The divalent aliphatic alkyl group is more preferably an alkylene group of a saturated aliphatic alkyl group. Examples of the divalent aliphatic alkyl group include straight-chain alkylene groups such as methylene, ethylene, trimethylene, tetramethylene, pentamethylene, and hexamethylene; and branched-chain alkylene groups such as ethylene (-CH(CH ₃ )-), propylene (-CH(CH ₂ CH ₃ )-), isopropylene (-C(CH _{3 ) 2} -), ethylmethylmethylene (-C(CH ₃ )(CH 2 CH ₃ )-), and diethylmethylene (-C(CH ₂ CH ₃ ) ₂ -). (A-1) When the specific maleimide compound contains two or more divalent aliphatic hydrocarbon groups in addition to the trimethylindane skeleton, these divalent aliphatic hydrocarbon groups may be the same or different.

The specific maleimide compound (A-1) preferably has a structure represented by the following formula (A4). The specific maleimide compound (A-1) may have the structure represented by the formula (A4) in its entirety or in part.

(In formula (A4), Ar ^a1 represents a divalent aromatic alkyl group which may have a substituent; ^Ra1 each independently represents an alkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, an alkylthio group having 1 to 10 carbon atoms, an aryl group having 6 to 10 carbon atoms, an aryloxy group having 6 to 10 carbon atoms, an arylthio group having 6 to 10 carbon atoms, a cycloalkyl group having 3 to 10 carbon atoms, a halogen atom, a nitro group, a hydroxyl group or a hydroxyl group; ^Ra2 each independently represents an alkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, an alkylthio group having 1 to 10 carbon atoms, an aryl group having 6 to 10 carbon atoms, an aryloxy group having 6 to 10 carbon atoms, an arylthio group having 6 to 10 carbon atoms, a cycloalkyl group having 3 to 10 carbon atoms, a halogen atom, a hydroxyl group or a hydroxyl group; R ^a3 each independently represents a divalent aliphatic alkyl group; n _a1 represents a positive integer; n _a2 each independently represents an integer of 0 to 4; n _a3 each independently represents an integer of 0 to 3; the hydrogen atom of the alkyl, alkoxy, alkylthio, aryl, aryloxy, arylthio and cycloalkyl group of ^Ra1 may be substituted by a halogen atom; the hydrogen atom of the alkyl, alkoxy, alkylthio, aryl, aryloxy, arylthio and cycloalkyl group of ^Ra2 may be substituted by a halogen atom; when n _a2 is 2 to 4, ^Ra1 may be the same or different in the same ring; when n _a3 is 2 to 3, ^Ra2 may be the same or different in the same ring).

In formula (A4), Ar ^a1 represents a divalent aromatic alkyl group which may have a substituent. The number of carbon atoms in the divalent aromatic alkyl group is preferably 6 or more, more preferably 20 or less, and particularly preferably 16 or less. Examples of the divalent aromatic alkyl group include phenylene and naphthylene. Examples of the substituent that the divalent aromatic alkyl group may have include an alkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, an alkylthio group having 1 to 10 carbon atoms, an aryl group having 6 to 10 carbon atoms, an aryloxy group having 6 to 10 carbon atoms, an arylthio group having 6 to 10 carbon atoms, a cycloalkyl group having 3 to 10 carbon atoms, a halogen atom, a hydroxyl group, and a hydroxyl group. The hydrogen atom of each substituent may be further substituted by a halogen atom. As specific examples of such substituents, for example, the same substituents as those capable of bonding to the benzene ring contained in the trimethylindane skeleton can be cited. When the divalent aromatic alkyl group has a substituent, the number of the substituents is preferably 1 to 4. When the number of substituents possessed by the divalent aromatic alkyl group is 2 or more, the 2 or more substituents may be the same or different. Among them, Ar ^a1 is preferably a divalent aromatic alkyl group having no substituent.

In formula (A4), ^Ra1 independently represents an alkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, an alkylthio group having 1 to 10 carbon atoms, an aryl group having 6 to 10 carbon atoms, an aryloxy group having 6 to 10 carbon atoms, an arylthio group having 6 to 10 carbon atoms, a cycloalkyl group having 3 to 10 carbon atoms, a halogen atom, a nitro group, a hydroxyl group or an alkyl group. The hydrogen atom of the alkyl group, the alkoxy group, the alkylthio group, the aryl group, the aryloxy group, the arylthio group and the cycloalkyl group may be substituted with a halogen atom. As specific examples of such groups, for example, the same substituents as those capable of bonding to the benzene ring contained in the trimethylindane skeleton can be cited. Among them, R ^a1 is more preferably at least one group selected from the group consisting of an alkyl group having 1 to 4 carbon atoms, a cycloalkyl group having 3 to 6 carbon atoms, and an aryl group having 6 to 10 carbon atoms, and is particularly preferably an alkyl group having 1 to 4 carbon atoms.

In formula (A4), ^Ra2 independently represents an alkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, an alkylthio group having 1 to 10 carbon atoms, an aryl group having 6 to 10 carbon atoms, an aryloxy group having 6 to 10 carbon atoms, an arylthio group having 6 to 10 carbon atoms, a cycloalkyl group having 3 to 10 carbon atoms, a halogen atom, a hydroxyl group or a cycloalkyl group. The hydrogen atom of the alkyl group, the alkoxy group, the alkylthio group, the aryl group, the aryloxy group, the arylthio group and the cycloalkyl group may be substituted with a halogen atom. As specific examples of such groups, for example, the same substituents as those capable of bonding to the benzene ring contained in the trimethylindane skeleton can be cited. Among them, R ^a2 is more preferably one or more groups selected from the group consisting of an alkyl group having 1 to 4 carbon atoms, a cycloalkyl group having 3 to 6 carbon atoms, and an aryl group having 6 to 10 carbon atoms.

In formula (A4), each of Ra ^{and Ra3} independently represents a divalent aliphatic hydrocarbon group. The preferred range of the divalent aliphatic hydrocarbon group is as described above.

In formula (A4), n _a1 represents a positive integer. n _a1 is preferably 1 or more, more preferably 10 or less, and particularly preferably 8 or less.

In formula (A4), n _a2 each independently represents an integer of 0 to 4. n _a2 is preferably 2 or 3, and more preferably 2. The plurality of n _a2 may be different, but are preferably the same. When n _a2 is 2 or more, the plurality of R ^a1 may be the same or different in the same ring.

In formula (A4), n _a3 each independently represents an integer from 0 to 3. The multiple n _a3s may be different, but are preferably the same. _{n a3} is preferably 0.

The specific maleimide compound (A-1) particularly preferably has a structure represented by the following formula (A5). The specific maleimide compound (A-1) may have the structure represented by the formula (A5) in its entirety or in part.

(In formula (A5), R ^b1 each independently represents an alkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, an alkylthio group having 1 to 10 carbon atoms, an aryl group having 6 to 10 carbon atoms, an aryloxy group having 6 to 10 carbon atoms, an arylthio group having 6 to 10 carbon atoms, a cycloalkyl group having 3 to 10 carbon atoms, a halogen atom, a nitro group, a hydroxyl group or a hydroxyl group; R ^b2 each independently represents an alkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, an alkylthio group having 1 to 10 carbon atoms, an aryl group having 6 to 10 carbon atoms, an aryloxy group having 6 to 10 carbon atoms, an arylthio group having 6 to 10 carbon atoms, a cycloalkyl group having 3 to 10 carbon atoms, a halogen atom, a hydroxyl group or a hydroxyl group; n _b1 represents a positive integer; n _b2 each independently represents an integer from 0 to 4; _b3 each independently represents an integer of 0 to 3. The hydrogen atom of the alkyl, alkoxy, alkylthio, aryl, aryloxy, arylthio and cycloalkyl group of ^{R b1} may be substituted by a halogen atom. The hydrogen atom of the alkyl, alkoxy, alkylthio, aryl, aryloxy, arylthio and cycloalkyl group of R ^b2 may be substituted by a halogen atom. When _{n b2} is 2 to 4, R ^b1 may be the same or different in the same ring. When n _b3 is 2 to 3, R ^b2 may be the same or different in the same ring).

In the formula (A5), R ^b1 , R ^b2 , n _b1 , n _b2 and n _b3 are respectively the same as ^Ra1 , ^Ra2 , n _a1 , n _a2 and n _a3 in the formula (A4).

(A-1) The specific maleimide compound may further include a structure represented by the following formula (A6).

In formula (A6), R ^c1 , R ^c2 , n _c2 and n _c3 are respectively the same as ^Ra1 , ^Ra2 , n _a2 and n _a3 in formula (A4). In formula (A6), n _c1 is the number of repeating units and represents an integer from 1 to 20. In formula (A6), * represents a bond. For example, the specific maleimide compound (A-1) is a compound in formula (A4) in which n _a2 is 3 or less and there are 2 or more of the ortho and para positions relative to the maleimide group of the benzene ring to which the maleimide group is bonded, and when not bonded to ^Ra1 , it can be combined in the structure represented by formula (A4) and include the structure represented by the aforementioned formula (A6). Furthermore, for example, the specific maleimide compound (A-1) is in formula (A5), n _b2 is 3 or less, and there are 2 or more ortho- and para-positions relative to the maleimide group of the benzene ring to which the maleimide group is bonded, and when R ^b1 is not bonded, it can be combined in the structure represented by formula (A5) and include the structure represented by the aforementioned formula (A6).

The (A-1) specific maleimide compound as the component (A-1) may be used alone or in combination of two or more thereof at an arbitrary ratio.

The maleimide group equivalent of the specific maleimide compound (A-1) is preferably 50 g/eq. or more, more preferably 100 g/eq. or more, particularly preferably 200 g/eq. or more, and preferably 2000 g/eq. or less, more preferably 1000 g/eq. or less, particularly preferably 800 g/eq. or less. The maleimide group equivalent represents the mass of the maleimide compound per 1 equivalent of maleimide groups. When the maleimide group equivalent of the specific maleimide compound (A-1) is within the above range, the effect of the present invention can be significantly obtained.

The amount of the specific maleimide compound (A-1) in the resin composition is preferably 0.1% by mass or more, more preferably 0.5% by mass or more, particularly preferably 1% by mass or more, and preferably 70% by mass or less, more preferably 60% by mass or less, particularly preferably 50% by mass or less, relative to 100% by mass of the non-volatile components in the resin composition. When the amount of the specific maleimide compound (A-1) is within the above range, the effect of the present invention can be significantly obtained.

The amount of the (A-1) specific maleimide compound in the resin composition is preferably 0.5% by mass or more, more preferably 1% by mass or more, particularly preferably 2% by mass or more, and preferably 70% by mass or less, more preferably 60% by mass or less, particularly preferably 50% by mass or less, relative to 100% by mass of the resin component in the resin composition. The resin component in the resin composition refers to the component other than the (D) inorganic filler among the non-volatile components in the resin composition. When the amount of the (A-1) specific maleimide compound is within the above range, the effect of the present invention can be significantly obtained.

The amount of the specific maleimide compound (A-1) in the resin composition is preferably 60% by mass or more, more preferably 80% by mass or more, particularly preferably 100% by mass or more, and preferably 200% by mass or less, more preferably 180% by mass or less, particularly preferably 160% by mass or less, based on 100% by mass of the radical polymerizable aromatic resin (B) in the resin composition. When the amount of the specific maleimide compound (A-1) is within the above range, the effect of the present invention can be significantly obtained.

The ratio of the total number of maleimide groups of the (A-1) specific maleimide compound to the total number of epoxy groups of the (B) epoxy resin (maleimide group/epoxy group) is preferably within a specific range. The aforementioned ratio (maleimide group/epoxy group) is preferably 0.01 or more, more preferably 0.3 or more, particularly preferably 0.5 or more, and preferably 5 or less, more preferably 3 or less, particularly preferably 2 or less. The "total number of maleimide groups of the (A-1) specific maleimide compound" is a value obtained by dividing the mass of the non-volatile components of the (A-1) specific maleimide compound present in the resin composition by the maleimide group equivalent, and adding all the values together. Furthermore, the "(B) total number of epoxy groups in the epoxy resin" is the value obtained by dividing the mass of the non-volatile components of the epoxy resin present in the resin composition by the epoxy equivalent, and giving the total value. When the aforementioned ratio (maleimide group/epoxy group) is within the aforementioned range, the effect of the present invention can be significantly obtained.

The amount of the specific maleimide compound (A-1) in the resin composition is preferably 10% by mass or more, more preferably 20% by mass or more, particularly preferably 30% by mass or more, and preferably 160% by mass or less, more preferably 130% by mass or less, particularly preferably 110% by mass or less, based on 100% by mass of the active ester hardener (C) in the resin composition. When the amount of the specific maleimide compound (A-1) is within the above range, the effect of the present invention can be significantly obtained.

The ratio of the total number of maleimide groups of the (A-1) specific maleimide compound to the total number of active ester groups of the (C) active ester curing agent (maleimide group/active ester group) is preferably within a specific range. The aforementioned ratio (maleimide group/active ester group) is preferably 0.01 or more, more preferably 0.3 or more, particularly preferably 0.5 or more, and is preferably 5 or less, more preferably 3 or less, particularly preferably 2 or less. The so-called "total number of active ester groups of the (C) active ester curing agent" is a value obtained by dividing the mass of the non-volatile components of the (C) active ester curing agent present in the resin composition by the active ester equivalent, and adding all the values together. When the aforementioned ratio (maleimide group/active ester group) is within the aforementioned range, the effect of the present invention can be significantly obtained.

The amount of the specific maleimide compound (A-1) in the resin composition is preferably 30% to 100% by mass, more preferably 40% to 100% by mass, and particularly preferably 50% to 100% by mass, relative to 100% by mass of the total amount of the maleimide compound (A). When the amount of the specific maleimide compound (A-1) is within the above range, the effect of the present invention can be significantly obtained.

The method for producing the (A-1) specific maleimide compound is not particularly limited. The (A-1) specific maleimide compound can be produced, for example, by the method described in the Japan Invention Association Publication No. 2020-500211. According to the production method described in the Japan Invention Association Publication No. 2020-500211, a maleimide compound having a distribution in the number of repeating units of the trimethylindane skeleton can be obtained. The maleimide compound obtained by this method includes the structure shown in the following formula (A1). Therefore, the (A) maleimide compound may include a maleimide compound containing the structure shown in formula (A1).

(In formula (A1), ^R1 each independently represents an alkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, an alkylthio group having 1 to 10 carbon atoms, an aryl group having 6 to 10 carbon atoms, an aryloxy group having 6 to 10 carbon atoms, an arylthio group having 6 to 10 carbon atoms, a cycloalkyl group having 3 to 10 carbon atoms, a halogen atom, a nitro group, a hydroxyl group or a hydroxyl group; R2 ^each independently represents an alkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, an alkylthio group having 1 to 10 carbon atoms, an aryl group having 6 to 10 carbon atoms, an aryloxy group having 6 to 10 carbon atoms, an arylthio group having 6 to 10 carbon atoms, a cycloalkyl group having 3 to 10 carbon atoms, a halogen atom, a hydroxyl group or a hydroxyl group; _n1 represents an average number of repeating units of 0.95 to 10.0; n _n2 each independently represents an integer from 0 to 4; _n3 each independently represents an integer from 0 to 3. The hydrogen atom of the alkyl, alkoxy, alkylthio, aryl, aryloxy, arylthio and cycloalkyl group represented by ^R1 may be substituted by a halogen atom. The hydrogen atom of the alkyl, alkoxy, alkylthio, aryl, aryloxy, arylthio and cycloalkyl group represented by ^R2 may be substituted by a halogen atom. When _n2 is 2 to 4, ^R1 may be the same or different in the same ring. When _n3 is 2 to 3, ^R2 may be the same or different in the same ring).

In the formula (A1), R ¹ , R ² , n ₂ and n ₃ are the same as ^Ra1 , ^Ra2 , n _a2 and n _a3 in the formula (A4), respectively.

In formula (A1), _n1 represents the average number of repeating units, and the range is 0.95 to 10.0. According to the production method described in the Japanese Invention Patent Publication No. 2020-500211, a group of maleimide compounds containing the structure represented by formula (A1) can be obtained. As can be seen from the fact that the average number of repeating units _n1 in formula (A1) can be less than 1.00, the maleimide compounds containing the structure represented by (A1) obtained in this way can include a maleimide compound having a repeating unit number of 0 in the trimethylindane skeleton. Therefore, from the maleimide compound having a structure represented by formula (A1), the maleimide compound having a repeating unit number of 0 in the trimethylindane skeleton is purified to obtain the specific maleimide compound (A-1), and the resin composition may contain only the obtained specific maleimide compound (A-1). However, even when the maleimide compound having a repeating unit number of 0 in the trimethylindane skeleton is contained in the resin composition, the effect of the present invention can be obtained. In addition, when the purification is omitted, the cost can be suppressed. Therefore, it is preferred that the maleimide compound having a repeating unit number of 0 in the trimethylindane skeleton is not removed, and the resin composition contains the maleimide compound having a structure represented by formula (A1).

In formula (A1), the average repeating unit number _n1 is preferably 0.95 or more, more preferably 0.98 or more, particularly preferably 1.0 or more, particularly preferably 1.1 or more, and is preferably 10.0 or less, more preferably 8.0 or less, particularly preferably 7.0 or less, particularly preferably 6.0 or less. When the average repeating unit number _n1 is within the above range, the effect of the present invention can be significantly obtained. In particular, the glass transition temperature of the resin composition can be effectively increased.

As examples of the structure represented by formula (A1), the following can be cited.

The maleimide compound containing the structure represented by formula (A1) may further include the structure represented by the aforementioned formula (A6). For example, in the maleimide compound containing the structure represented by formula (A1), in formula (A1), _n2 is 3 or less, and when there are 2 or more ortho- and para-positions relative to the maleimide group of the benzene ring to which the maleimide group is bonded, and ^R1 is not bonded, the structure represented by formula (A1) may be combined to include the structure represented by formula (A6).

The molecular weight distribution Mw/Mn of the maleimide compound having the structure represented by formula (A1) is preferably within a specific range as measured by gel permeation chromatography (GPC). The molecular weight distribution is the value obtained by dividing the weight average molecular weight Mw by the number average molecular weight Mn, and is represented by "Mw/Mn". Specifically, the molecular weight distribution Mw/Mn of the maleimide compound having the structure represented by formula (A1) is preferably 1.0 to 4.0, more preferably 1.1 to 3.8, particularly preferably 1.2 to 3.6, and particularly preferably 1.3 to 3.4. When the molecular weight distribution Mw/Mn of the maleimide compound having the structure represented by formula (A1) is within the aforementioned range, the effect of the present invention can be significantly obtained.

In the maleimide compound having a structure represented by formula (A1), the amount of the maleimide compound having an average repeating unit number _n1 of 0 is preferably within a specific range. When the maleimide compound having a structure represented by formula (A1) is subjected to the aforementioned GPC measurement, the amount of the maleimide compound having an average repeating unit number _n1 of 0 can be expressed as area % based on the result of the GPC measurement. Specifically, in the chromatogram obtained by the aforementioned GPC measurement, the amount of the maleimide compound having an average repeating unit number n1 of 0 can be expressed by the ratio (area %) of the area of the peak of the maleimide compound having an average repeating unit number _n1 of 0 relative to the total area of the peak of the maleimide compound having a structure represented by formula ( _A1 ). Specifically, the amount of the maleimide compound having an average repeating unit number _n1 of 0 is preferably 32 area % or less, more preferably 30 area % or less, and particularly preferably 28 area % or less, relative to 100 area % of the total amount of the maleimide compound having the structure represented by formula (A1). When the amount of the maleimide compound having an average repeating unit number _n1 of 0 is within the above range, the effect of the present invention can be significantly obtained.

The maleimide group equivalent of the maleimide compound having the structure represented by formula (A1) is preferably in the same range as the maleimide group equivalent of the specific maleimide compound (A-1) described above. When the maleimide group equivalent of the maleimide compound having the structure represented by formula (A1) is in the above range, the effect of the present invention can be significantly obtained.

The amount of the maleimide compound having a structure represented by formula (A1) is preferably 0.1% by mass or more, more preferably 0.5% by mass or more, particularly preferably 1% by mass or more, and preferably 70% by mass or less, more preferably 60% by mass or less, particularly preferably 50% by mass or less, relative to 100% by mass of the non-volatile components in the resin composition. When the amount of the maleimide compound having a structure represented by formula (A1) is within the above range, the effect of the present invention can be significantly obtained.

The amount of the maleimide compound having a structure represented by formula (A1) is preferably 0.5% by mass or more, more preferably 1% by mass or more, particularly preferably 2% by mass or more, and preferably 70% by mass or less, more preferably 60% by mass or less, particularly preferably 50% by mass or less, relative to 100% by mass of the resin component in the resin composition. When the amount of the maleimide compound having a structure represented by formula (A1) is within the above range, the effect of the present invention can be significantly obtained.

The amount of the maleimide compound having a structure represented by formula (A1) is preferably 60% by mass or more, more preferably 80% by mass or more, particularly preferably 100% by mass or more, and preferably 200% by mass or less, more preferably 180% by mass or less, particularly preferably 160% by mass or less, relative to 100% by mass of the epoxy resin (B) in the resin composition. When the amount of the maleimide compound having a structure represented by formula (A1) is within the above range, the effect of the present invention can be significantly obtained.

The ratio of the total number of maleimide groups of the maleimide compound having the structure represented by formula (A1) to the total number of epoxy groups of the epoxy resin (B) (maleimide group/epoxy group) is preferably within a specific range. The aforementioned ratio (maleimide group/epoxy group) is preferably 0.01 or more, more preferably 0.3 or more, particularly preferably 0.5 or more, and preferably 5 or less, more preferably 3 or less, and particularly preferably 2 or less. The so-called "total number of maleimide groups of the maleimide compound having the structure represented by formula (A1)" is the value obtained by dividing the mass of the non-volatile components of the maleimide compound having the structure represented by formula (A1) in the resin composition by the maleimide group equivalent, and giving the total value. When the above ratio (maleimide group/epoxy group) is within the above range, the effect of the present invention can be significantly obtained.

The amount of the maleimide compound having a structure represented by formula (A1) is preferably 10% by mass or more, more preferably 20% by mass or more, particularly preferably 30% by mass or more, and preferably 160% by mass or less, more preferably 130% by mass or less, particularly preferably 110% by mass or less, relative to 100% by mass of the active ester hardener (C) in the resin composition. When the amount of the maleimide compound having a structure represented by formula (A1) is within the above range, the effect of the present invention can be significantly obtained.

The ratio of the total number of maleimide groups of the maleimide compound having the structure represented by formula (A1) to the total number of active ester groups of the active ester curing agent (C) (maleimide group/active ester group) is preferably within a specific range. The aforementioned ratio (maleimide group/active ester group) is preferably 0.01 or more, more preferably 0.3 or more, particularly preferably 0.5 or more, and is preferably 5 or less, more preferably 3 or less, particularly preferably 2 or less. When the aforementioned ratio (maleimide group/active ester group) is within the aforementioned range, the effect of the present invention can be significantly obtained.

The amount of the maleimide compound having a structure represented by formula (A1) is preferably 30% to 100% by mass, more preferably 40% to 100% by mass, and particularly preferably 50% to 100% by mass, relative to 100% by mass of the total amount of the maleimide compound (A). When the amount of the maleimide compound having a structure represented by formula (A1) is within the above range, the effect of the present invention can be significantly obtained.

(A) The maleimide compound can be combined with the above-mentioned (A-1) specific maleimide compound, and further includes any maleimide compound that does not contain a trimethylindane skeleton. Examples of the any maleimide compound include (A-2) biphenyl maleimide compounds and (A-3) aliphatic maleimide compounds. Any maleimide compound can be used alone or in combination of two or more at any ratio.

(A-2) The biphenyl maleimide compound refers to a maleimide compound containing a biphenyl skeleton. When the biphenyl maleimide compound (A-2) is used in combination with the specific maleimide compound (A-1), the plating peel strength can be effectively improved.

The benzene ring of the biphenyl skeleton contained in the (A-2) biphenyl maleimide compound may be bonded to 1 or 2 or more substituents. Examples of the substituent include a halogen atom, -OH, -OC _1-10 alkyl, -N(C _1-10 alkyl) ₂ , C _1-10 alkyl, C _6-10 aryl, -NH ₂ , -CN, -C(O)OC _1-10 alkyl, -COOH, -C(O)H, -NO ₂ , etc. Here, the term "C _xy " (x and y are positive integers satisfying x＜y) means that the number of carbon atoms of the organic group immediately following the term is x to y. For example, the expression "C _1-10 alkyl" means an alkyl group having 1 to 10 carbon atoms. These substituents may be bonded to each other to form a ring. The aforementioned ring also includes a spiro ring or a condensed ring. The aforementioned substituent may further have a substituent (hereinafter also referred to as a "secondary substituent"). As the secondary substituent, the same as the aforementioned substituent may be used. Among them, it is preferred that the substituent is not bonded to the benzene ring of the biphenyl skeleton contained in the (A-2) biphenyl type maleimide compound.

The (A-2) biphenyl type maleimide compound is preferably a compound having a biphenyl skeleton and containing either an aliphatic alkyl group or an aromatic alkyl group, and more preferably a compound having both an aliphatic alkyl group and an aromatic alkyl group. As a preferred (A-2) biphenyl type maleimide compound, there can be mentioned a maleimide compound represented by the following formula (A7).

(In formula (A7), ^Rd1 each independently represents an alkylene group; ^Rd2 each independently represents an alkyl group which may have a substituent or an aryl group which may have a substituent; ^Rd3 each independently represents a substituent; _{nd1 each} independently represents an integer from 1 to 100; _nd2 each independently represents an integer from 0 to 2; and _nd3 each independently represents an integer from 0 to 4).

In formula (A7), ^Rd1 each independently represents an alkylene group. The number of carbon atoms in the alkylene group is preferably 1 to 10, more preferably 1 to 6, and particularly preferably 1 to 3. The alkylene group is preferably a linear alkylene group, and more preferably a methylene group.

In formula (A7), ^Rd2 each independently represents an alkyl group which may have a substituent or an aryl group which may have a substituent. The number of carbon atoms of the alkyl group is preferably 1 to 10, more preferably 1 to 6, and particularly preferably 1 to 3. The alkyl group may be any of a linear, branched, or cyclic shape. In addition, as a substituent that the alkyl group may have, for example, the same examples as those mentioned above as the substituent that can be bonded to the benzene ring of the biphenyl skeleton can be cited. The number of carbon atoms of the aryl group is preferably 6 to 20, more preferably 6 to 15, and particularly preferably 6 to 10. As a substituent that the aryl group may have, for example, the same examples as those mentioned above as the substituent that can be bonded to the benzene ring of the biphenyl skeleton can be cited.

In formula (A7), ^Rd3 each independently represents a substituent. Examples of such a substituent include the same substituents as those described above as the substituents capable of bonding to the benzene ring of the biphenyl skeleton.

In formula (A7), _nd1 represents an integer of 1 to 100, preferably 1 to 50, more preferably 1 to 20, and even more preferably 1 to 5.

In formula (A7), n _{and d2} each independently represent an integer from 0 to 2, preferably 0.

In formula (A7), n _{and d3} each independently represent an integer of 0 to 4, preferably 0 to 3, more preferably 0 or 1, and particularly preferably 0.

Examples of the (A-2) biphenyl maleimide compound represented by formula (A7) include "MIR-3000-70MT" manufactured by Nippon Kayaku Co., Ltd. (main component: compound represented by the following formula (A8)). In the following formula (A8), n _d4 represents 1 or 2.

The amount of the biphenyl maleimide compound (A-2) is preferably 0.1% by mass or more, more preferably 0.5% by mass or more, particularly preferably 1.0% by mass or more, and preferably 10.0% by mass or less, more preferably 6.0% by mass or less, particularly preferably 4.0% by mass or less, relative to 100% by mass of the non-volatile components in the resin composition. When the amount of the biphenyl maleimide compound (A-2) is within the above range, the effect of the present invention can be significantly obtained.

The amount of the biphenyl maleimide compound (A-2) is preferably 0.1% by mass or more, more preferably 0.5% by mass or more, particularly preferably 1.0% by mass or more, and is preferably 20% by mass or less, more preferably 15% by mass or less, particularly preferably 10% by mass or less, relative to 100% by mass of the resin component in the resin composition. When the amount of the biphenyl maleimide compound (A-2) is within the above range, the effect of the present invention can be significantly obtained.

(A-3) The aliphatic maleimide compound refers to a maleimide compound containing an aliphatic alkyl group having 5 or more carbon atoms. When the aliphatic maleimide compound (A-3) is used in combination with the specific maleimide compound (A-1), the plating peel strength can be effectively improved.

The carbon number of the aliphatic alkyl group contained in the (A-3) aliphatic maleimide compound is usually 5 or more, preferably 6 or more, more preferably 8 or more, and is preferably 50 or less, more preferably 45 or less, and particularly preferably 40 or less.

The aliphatic hydrocarbon group contained in the (A-3) aliphatic maleimide compound may be saturated or unsaturated, and a saturated aliphatic hydrocarbon group is preferred. The aliphatic hydrocarbon group may be a chain group or a ring group. The aliphatic hydrocarbon group may be a monovalent group or a divalent group.

Examples of the aliphatic alkyl group contained in the aliphatic maleimide compound (A-3) include alkyl groups such as pentyl, hexyl, heptyl, octyl, nonyl and decyl; and alkylene groups such as a pentyl group, a hexyl group, a heptyl group, a octyl group, a nonyl group, a decyl group, a undecyl group, a dodecanyl group, a tridecyl group, a heptadecan ... and a heptadecanyl group.

The aliphatic alkyl group contained in the aliphatic maleimide compound (A-3) may be bonded to a substituent. As the substituent, for example, the same substituent as that which can be bonded to the benzene ring of the biphenyl skeleton in the description of the biphenyl maleimide compound (A-2) may be cited. Among them, it is preferred that the aliphatic alkyl group contained in the aliphatic maleimide compound (A-3) is not bonded to a substituent.

The (A-3) aliphatic maleimide compound preferably has a polyimide structure. Preferred (A-3) aliphatic maleimide compound includes a maleimide-terminated polyimide compound represented by the following formula (A9).

(In formula (A9), each R ^e1 independently represents a divalent aliphatic alkyl group having 5 or more carbon atoms which may have a substituent; each R ^e2 independently represents a divalent linking group; and each n _e1 represents an integer from 1 to 10).

In formula (A9), each of R ^e1 independently represents a divalent aliphatic alkyl group having 5 or more carbon atoms which may have a substituent. R ^e1 preferably represents an alkylene group, an alkenylene group or a polyalkylene group (the number of double bonds is preferably 2) having 5 or more carbon atoms which may have a substituent. ^{R a1} preferably includes an alkylene group having 5 or more carbon atoms which may have a substituent, in which case the alkylene group having 5 or more carbon atoms may be a part of the alkenylene group or the polyalkylene group. Specifically, the number of carbon atoms in R ^e1 is usually 5 or more, preferably 6 or more, more preferably 8 or more, and preferably 50 or less, more preferably 45 or less, and particularly preferably 40 or less. As the substituents that the divalent aliphatic hydrocarbon groups such as alkylene, alkenylene and polyalkylene can have, for example, the same examples as those mentioned above as the substituents that can be bonded to the benzene ring of the biphenyl skeleton in the description of the biphenyl maleimide compound (A-2) can be cited. Among them, R ^e1 is preferably a divalent aliphatic hydrocarbon group having no substituent, and more preferably an alkylene group having no substituent.

In formula (A9), R ^e2 each independently represents a divalent linking group. As the divalent linking group, a divalent group composed of an oxygen atom, an arylene group, an alkylene group or a combination of two or more of these groups is preferred. The number of carbon atoms in the arylene group is preferably 6 to 24, more preferably 6 to 18, particularly preferably 6 to 14, and particularly preferably 6 to 10. Examples of preferred arylene groups include phenylene groups, naphthylene groups, anthracenyl groups, and the like. The number of carbon atoms in the alkylene group is preferably 1 to 50, more preferably 1 to 45, and particularly preferably 1 to 40. The alkylene group may be any of a linear, branched, or cyclic shape. Preferred alkylene groups include, for example, methyl ethylene, cyclohexylene, pentylene, hexylene, heptylene, octylene, nonylene, decylene, undecylene, dodecanylene, tridecylene, heptadecanylene, trihexadecylene, a group having an octyl-cyclohexyl structure, a group having an octyl-cyclohexyl-octyl structure, a group having a propyl-cyclohexyl-octyl structure, etc. Among them, R ^e2 is preferably an oxygen atom.

In formula (A9), _ne1 represents an integer from 1 to 10.

Examples of the (A-3) aliphatic maleimide compound represented by formula (A9) include "BMI-1500" (compound of formula (A10), compound of formula (A12)) and "BMI-1700" (compound of formula (A11), compound of formula (A13)) manufactured by Designer Molecules. In the following formulas (A10), (A11), (A12) and (A13), _ne2 , _ne3 , _ne4 and _ne5 each independently represent an integer of 1 to 10.

The amount of the aliphatic maleimide compound (A-3) is preferably 0.1% by mass or more, more preferably 0.5% by mass or more, particularly preferably 1.0% by mass or more, and is preferably 10.0% by mass or less, more preferably 6.0% by mass or less, particularly preferably 4.0% by mass or less, relative to 100% by mass of the non-volatile components in the resin composition. When the amount of the aliphatic maleimide compound (A-3) is within the above range, the effects of the present invention can be significantly obtained.

The amount of the aliphatic maleimide compound (A-3) is preferably 0.1% by mass or more, more preferably 0.5% by mass or more, particularly preferably 1.0% by mass or more, and is preferably 20% by mass or less, more preferably 15% by mass or less, particularly preferably 10% by mass or less, relative to 100% by mass of the resin component in the resin composition. When the amount of the aliphatic maleimide compound (A-3) is within the above range, the effect of the present invention can be significantly obtained.

The maleimide group equivalent of any maleimide compound such as (A-2) biphenyl maleimide compound and (A-3) aliphatic maleimide compound is preferably in the same range as the maleimide group equivalent of the above-mentioned specific maleimide compound (A-1). When the maleimide group equivalent of any maleimide compound is in the above range, the effect of the present invention can be significantly obtained.

The amount of the (A) maleimide compound is preferably 0.1% by mass or more, more preferably 0.5% by mass or more, particularly preferably 1% by mass or more, and preferably 70% by mass or less, more preferably 60% by mass or less, particularly preferably 50% by mass or less, relative to 100% by mass of the non-volatile components in the resin composition. When the amount of the (A) maleimide compound is within the above range, the effect of the present invention can be significantly obtained.

The amount of the (A) maleimide compound is preferably 0.5% by mass or more, more preferably 1% by mass or more, particularly preferably 2% by mass or more, and preferably 70% by mass or less, more preferably 60% by mass or less, particularly preferably 50% by mass or less, relative to 100% by mass of the resin component in the resin composition. When the amount of the (A) maleimide compound is within the above range, the effect of the present invention can be significantly obtained.

The amount of the (A) maleimide compound is preferably 60% by mass or more, more preferably 80% by mass or more, particularly preferably 100% by mass or more, and preferably 200% by mass or less, more preferably 180% by mass or less, particularly preferably 160% by mass or less, relative to 100% by mass of the (B) epoxy resin in the resin composition. When the amount of the (A) maleimide compound is within the above range, the effect of the present invention can be significantly obtained.

The ratio of the total number of maleimide groups of the (A) maleimide compound to the total number of epoxy groups of the (B) epoxy resin (maleimide group/epoxy group) is preferably within a specific range. The aforementioned ratio (maleimide group/epoxy group) is preferably 0.01 or more, more preferably 0.3 or more, particularly preferably 0.5 or more, and preferably 5 or less, more preferably 3 or less, particularly preferably 2 or less. The so-called "total number of maleimide groups of the (A) maleimide compound" is the value obtained by dividing the mass of the non-volatile components of the (A) maleimide compound present in the resin composition by the maleimide group equivalent, and giving the total value. When the ratio (maleimide group/epoxy group) is within the above range, the effect of the present invention can be significantly obtained.

The amount of the (A) maleimide compound is preferably 10% by mass or more, more preferably 20% by mass or more, particularly preferably 30% by mass or more, and preferably 160% by mass or less, more preferably 130% by mass or less, particularly preferably 110% by mass or less, relative to 100% by mass of the (C) active ester hardener in the resin composition. When the amount of the (A) maleimide compound is within the above range, the effect of the present invention can be significantly obtained.

The ratio of the total number of maleimide groups of the (A) maleimide compound to the total number of active ester groups of the (C) active ester curing agent (maleimide group/active ester group) is preferably within a specific range. The aforementioned ratio (maleimide group/active ester group) is preferably 0.01 or more, more preferably 0.3 or more, particularly preferably 0.5 or more, and is preferably 5 or less, more preferably 3 or less, particularly preferably 2 or less. When the aforementioned ratio (maleimide group/active ester group) is within the aforementioned range, the effect of the present invention can be significantly obtained.

[3. (B) Epoxy resin] The epoxy resin as the component (B) contained in the resin composition includes curable resins having epoxy groups, such as dimethylol epoxy resins, bisphenol A epoxy resins, bisphenol F epoxy resins, bisphenol S epoxy resins, bisphenol AF type epoxy resin, dicyclopentadiene type epoxy resin, trisphenol type epoxy resin, naphthol novolac type epoxy resin, phenol novolac type epoxy resin, tert-butylcatechol type epoxy resin, naphthalene type epoxy resin, naphthol type epoxy resin, anthracene type epoxy resin, glycidyl Amine type epoxy resin, epoxy propyl ester type epoxy resin, cresol novolac type epoxy resin, phenol aralkyl type epoxy resin, biphenyl type epoxy resin, linear aliphatic epoxy resin, epoxy resin with butadiene structure, alicyclic epoxy resin, hybrid epoxy resin, spirocyclic epoxy resin Epoxy resins of the type described herein may include epoxy resins of the type described herein, epoxide resins of the type described herein, epoxide resins of the type described herein, epoxide resins of the type described herein, epoxide resins of the type described herein, epoxide resins of the type described herein, epoxide resins of the type described herein, epoxide resins of the type described herein, epoxide resins of the type described herein, epoxide resins of the type described herein, epoxide resins of the type described herein, epoxide resins of the type described herein, epoxide resins of the type described herein, epoxide resins of the type described herein, epoxide resins of the type described herein, epoxide resins of the type described herein, epoxide resins of the type described herein, epoxide resins of the type described herein, epoxide resins of the type described herein, epoxide resins of the type described herein, epoxide resins of the type described herein, epoxide resins of the type described herein, epoxide resins of the type described herein, epoxide resins of the type described herein, epoxide resins of the type described herein, epoxide resins of the type described herein,

The resin composition preferably contains an epoxy resin having two or more epoxy groups in one molecule as the epoxy resin (B). The proportion of the epoxy resin having two or more epoxy groups in one molecule relative to 100% by mass of the non-volatile component of the epoxy resin (B) is preferably 50% by mass or more, more preferably 60% by mass or more, and particularly preferably 70% by mass or more.

Among epoxy resins, there are epoxy resins that are liquid at a temperature of 20°C (hereinafter also referred to as "liquid epoxy resin") and epoxy resins that are solid at a temperature of 20°C (hereinafter also referred to as "solid epoxy resin"). The resin composition may contain only a liquid epoxy resin, only a solid epoxy resin, or a combination of a liquid epoxy resin and a solid epoxy resin as the epoxy resin (B). Among them, it is more preferable to use only a liquid epoxy resin as the epoxy resin (B).

The liquid epoxy resin is preferably a liquid epoxy resin having two or more epoxy groups in one molecule.

As the liquid epoxy resin, preferred are bisphenol A type epoxy resin, bisphenol F type epoxy resin, bisphenol AF type epoxy resin, naphthalene type epoxy resin, glycidyl ester type epoxy resin, glycidyl amine type epoxy resin, phenol novolac type epoxy resin, alicyclic epoxy resin having an ester skeleton, cyclohexane type epoxy resin, cyclohexanedimethanol type epoxy resin and epoxy resin having a butadiene structure.

Specific examples of liquid epoxy resins include "HP-4032", "HP-4032-D", and "HP-4032-SS" (naphthalene-based epoxy resins) manufactured by DIC Corporation; "828US", "828EL", "jER828EL", "825", and "Epikote" manufactured by Mitsubishi Chemical Corporation. "828EL" (bisphenol A type epoxy resin); "jER807" and "1750" (bisphenol F type epoxy resin) manufactured by Mitsubishi Chemical; "jER152" (phenol novolac type epoxy resin) manufactured by Mitsubishi Chemical; "630", "630LSD", and "604" (epoxypropylamine type epoxy resin) manufactured by Mitsubishi Chemical; "ED-52 3T" (glycyrrhizin type epoxy resin); "EP-3950L" and "EP-3980S" (epoxypropylamine type epoxy resin) manufactured by ADEKA; "EP-4088S" (dicyclopentadiene type epoxy resin) manufactured by ADEKA; "ZX1059" (a mixture of bisphenol A type epoxy resin and bisphenol F type epoxy resin) manufactured by Nippon Steel & Sumitomo Chemicals; Nagase "EX-721" manufactured by ChemteX (epoxypropyl ester type epoxy resin); "Celloxide 2021P" manufactured by DAICEL (lipidic epoxy resin with ester skeleton); "PB-3600" manufactured by DAICEL, "JP-100" and "JP-200" manufactured by Nippon Soda (epoxy resin with butadiene structure); "ZX1658" and "ZX1658GS" manufactured by Nippon Steel & Sumitomo Chemicals (liquid 1,4-epoxypropyl cyclohexane type epoxy resin), etc. These can be used alone or in combination of two or more.

The solid epoxy resin is preferably a solid epoxy resin having three or more epoxy groups in one molecule, and more preferably an aromatic solid epoxy resin having three or more epoxy groups in one molecule.

As the solid epoxy resin, preferred are biphenylol type epoxy resin, naphthalene type epoxy resin, naphthalene type tetrafunctional epoxy resin, naphthol novolac type epoxy resin, cresol novolac type epoxy resin, dicyclopentadiene type epoxy resin, trisphenol type epoxy resin, naphthol type epoxy resin, Resins, biphenyl type epoxy resins, naphthyl ether type epoxy resins, anthracene type epoxy resins, bisphenol A type epoxy resins, bisphenol AF type epoxy resins, phenol aralkyl type epoxy resins, tetraphenylethane type epoxy resins, phenol o-phthalimide type epoxy resins, phenolphthalein type epoxy resins.

Specific examples of solid epoxy resins include "HP4032H" (naphthalene-based epoxy resin) manufactured by DIC Corporation; "HP-4700" and "HP-4710" (naphthalene-based tetrafunctional epoxy resin) manufactured by DIC Corporation; "N-690" (cresol novolac-based epoxy resin) manufactured by DIC Corporation; "N-695" (cresol novolac-based epoxy resin) manufactured by DIC Corporation; "HP-7200", "HP-7200HH", "HP-7200H", and "HP-7200L" (dicyclopentadiene-based epoxy resin) manufactured by DIC Corporation; "EXA-7311", "EXA-7311-G3", "EXA-7311-G4", "EXA-7311-G4S", "HP6000" (naphthyl ether type epoxy resin) manufactured by Company C; "EPPN-502H" (triphenol type epoxy resin) manufactured by Nippon Kayaku Co., Ltd.; "NC7000L" (naphthol novolac type epoxy resin) manufactured by Nippon Kayaku Co., Ltd.; "NC3000H", "NC3000", "NC3000L", "NC3000FH", "NC3100" (biphenyl type epoxy resin) manufactured by Nippon Kayaku Co., Ltd. ); "ESN475V" manufactured by Nippon Steel Chemicals & Materials Co., Ltd. (naphthalene type epoxy resin); "ESN485" manufactured by Nippon Steel Chemicals & Materials Co., Ltd. (naphthol type epoxy resin); "ESN375" manufactured by Nippon Steel Chemicals & Materials Co., Ltd. (dihydroxynaphthalene type epoxy resin); "YX4000H", "YX4000", "YX4000HK", "YL7890" manufactured by Mitsubishi Chemical Corporation (biphenyl type epoxy resin); "YL6121" manufactured by Mitsubishi Chemical Corporation (biphenyl type epoxy resin); "YX8800" manufactured by Mitsubishi Chemical Corporation (anthracene type epoxy resin); Mitsubishi "YX7700" (phenol aralkyl type epoxy resin) manufactured by Osaka Gas Chemical Co., Ltd.; "PG-100" and "CG-500" manufactured by Osaka Gas Chemical Co., Ltd.; "YL7760" (bisphenol AF type epoxy resin) manufactured by Mitsubishi Chemical Co., Ltd.; "YL7800" (fluorene type epoxy resin) manufactured by Mitsubishi Chemical Co., Ltd.; "jER1010" (bisphenol A type epoxy resin) manufactured by Mitsubishi Chemical Co., Ltd.; "jER1031S" (tetraphenylethane type epoxy resin) manufactured by Mitsubishi Chemical Co., Ltd.; "WHR991S" (phenol o-phthalimide type epoxy resin) manufactured by Nippon Kayaku Co., Ltd., etc. These can be used alone or in combination of two or more.

(B) The epoxy equivalent of the epoxy resin is preferably 50 g/eq. to 5000 g/eq., more preferably 50 g/eq. to 3000 g/eq., particularly preferably 80 g/eq. to 2000 g/eq., and particularly preferably 110 g/eq. to 1000 g/eq. The epoxy equivalent represents the mass of the epoxy resin per 1 equivalent of epoxy group. The epoxy equivalent can be measured in accordance with JIS K7236.

(B) The weight average molecular weight (Mw) of the epoxy resin is preferably 100 to 5,000, more preferably 250 to 3,000, and particularly preferably 400 to 1,500. The weight average molecular weight of the resin can be measured as a value converted to polystyrene by gel permeation chromatography (GPC).

The amount of the epoxy resin (B) in the resin composition is not particularly limited, but is preferably 1% by mass or more, more preferably 3% by mass or more, particularly preferably 5% by mass or more, and preferably 50% by mass or less, more preferably 40% by mass or less, and particularly preferably 30% by mass or less, relative to 100% by mass of the non-volatile components in the resin composition. When the amount of the epoxy resin (B) is within the above range, the effect of the present invention can be significantly obtained.

The amount of the epoxy resin (B) in the resin composition is not particularly limited, but is preferably 3% by mass or more, more preferably 10% by mass or more, particularly preferably 20% by mass or more, and preferably 50% by mass or less, more preferably 40% by mass or less, and particularly preferably 30% by mass or less, relative to 100% by mass of the resin component in the resin composition. When the amount of the epoxy resin (B) is within the above range, the effect of the present invention can be significantly obtained.

[4. (C) Active ester hardener] The active ester hardener of the component (C) contained in the resin composition is a compound having one or more active ester groups in the molecule, which can react with the epoxy resin (B). The active ester hardener (C) can be used alone or in combination of two or more in any ratio.

As the (C) active ester curing agent, a compound having two or more highly reactive ester groups in one molecule, such as phenol esters, thiophenol esters, N-hydroxylamine esters, and esters of heterocyclic hydroxyl compounds, is preferred. The active ester curing agent is preferably obtained by a condensation reaction of a carboxylic acid compound and/or a thiocarboxylic acid compound with a hydroxyl compound and/or a thiol compound. In particular, from the viewpoint of improving heat resistance, an active ester curing agent obtained from a carboxylic acid compound and a hydroxyl compound is preferred, and an active ester curing agent obtained from a carboxylic acid compound and a phenol compound and/or a naphthol compound is more preferred.

Examples of the carboxylic acid compound include benzoic acid, acetic acid, succinic acid, maleic acid, itaconic acid, phthalic acid, isophthalic acid, terephthalic acid, and pyromellitic acid.

Examples of the phenol compound or naphthol compound include hydroquinone, resorcinol, bisphenol A, bisphenol F, bisphenol S, reduced phenolphthalein, methylated bisphenol A, methylated bisphenol F, methylated bisphenol S, phenol, o-cresol, m-cresol, p-cresol, catechol, α-naphthol, β-naphthol, 1,5-dihydroxynaphthalene, 1,6-dihydroxynaphthalene, 2,6-dihydroxynaphthalene, dihydroxydiphenyl ketone, trihydroxydiphenyl ketone, tetrahydroxydiphenyl ketone, phloroglucinol, benzenetriol, dicyclopentadiene-type diphenol compounds, and phenol novolac. Here, the so-called "dicyclopentadiene-type diphenol compound" refers to a diphenol compound obtained by condensing one dicyclopentadiene molecule and two phenol molecules.

Specifically, as (C) active ester-based curing agent, preferred are dicyclopentadiene type active ester compounds, naphthalene type active ester compounds containing naphthalene structure, active ester compounds containing acetylated phenol novolac, and active ester compounds containing benzoylated phenol novolac. Among them, at least one selected from dicyclopentadiene type active ester compounds and naphthalene type active ester compounds is more preferred, and dicyclopentadiene type active ester compounds are particularly preferred. As dicyclopentadiene type active ester compounds, preferred are active ester compounds containing dicyclopentadiene type diphenol structure. The so-called "dicyclopentadiene type diphenol structure" means a divalent structural unit composed of phenylene-dicyclopentylene-phenylene.

(C) As commercially available products of active ester curing agents, among active ester compounds containing a dicyclopentadiene-type diphenol structure, there can be cited "EXB-9451", "EXB-9460", "EXB-9460S", "HPC-8000", "HPC-8000-65T", "HPC-8000H", "HPC-8000H-65TM", "EXB-8000L", "EXB-800 0L-65M", "HPC-8000L-65TM", "EXB-8000L-65TM"; among the active ester compounds containing naphthalene structure, there are "EXB-8100L-65T", "HPC-8150-60T", "HPC-8150-62T", "EXB-8150-60T", "EXB-9416-70BK" (DIC), "PC1300-02" (AIR WATER Co., Ltd.); among the active ester compounds containing phosphorus, "EXB9401" (manufactured by DIC Corporation) can be cited; among the active ester compounds of acetylated phenol novolacs, "DC808" (manufactured by Mitsubishi Chemical Corporation) can be cited; among the active ester compounds of benzoylated phenol novolacs, "YLH1026" (manufactured by Mitsubishi Chemical Corporation), "YLH1030" (manufactured by Mitsubishi Chemical Corporation), and "YLH1048" (manufactured by Mitsubishi Chemical Corporation) can be cited; among the active ester compounds containing styryl groups, "PC1300-02-65MA" (manufactured by AIR WATER Co., Ltd.) and the like can be cited.

(C) The active ester group equivalent of the active ester curing agent is preferably 50 g/eq. to 500 g/eq., more preferably 50 g/eq. to 400 g/eq., and particularly preferably 100 g/eq. to 300 g/eq. The active ester group equivalent refers to the mass of the active ester compound per 1 equivalent of active ester group.

The amount of the active ester hardener (C) in the resin composition is not particularly limited, but is preferably 3% by mass or more, more preferably 6% by mass or more, particularly preferably 10% by mass or more, and is preferably 80% by mass or less, more preferably 60% by mass or less, and even more preferably 50% by mass or less, relative to 100% by mass of the non-volatile components in the resin composition. When the amount of the active ester hardener (C) is within the above range, the effect of the present invention can be significantly obtained.

The amount of the active ester hardener (C) in the resin composition is not particularly limited, but is preferably 6% by mass or more, more preferably 20% by mass or more, particularly preferably 30% by mass or more, preferably 80% by mass or less, more preferably 70% by mass or less, and particularly preferably 60% by mass or less, based on 100% by mass of the resin component in the resin composition. When the amount of the active ester hardener (C) is within the above range, the effect of the present invention can be significantly obtained.

The ratio of the total number of active ester groups of the active ester curing agent (C) to the total number of epoxy groups of the epoxy resin (B) (active ester group/epoxy group) is preferably within a specific range. The aforementioned ratio (active ester group/epoxy group) is preferably 0.1 or more, more preferably 0.5 or more, particularly preferably 0.8 or more, and is preferably 5 or less, more preferably 3 or less, particularly preferably 2 or less. When the aforementioned ratio (active ester group/epoxy group) is within the aforementioned range, the effect of the present invention can be significantly obtained.

[5. (D) Inorganic filler] The resin composition may further contain (D) an inorganic filler as an arbitrary component in addition to the above components. The inorganic filler of component (D) is usually contained in the resin composition in the form of particles.

As the material of the (D) inorganic filler, an inorganic compound can be used. Examples of the material of the (D) inorganic filler include silicon dioxide, aluminum oxide, glass, cordierite, silicon oxide, barium sulfate, barium carbonate, talc, clay, mica powder, zinc oxide, hydrotalcite, alumina, aluminum hydroxide, magnesium hydroxide, calcium carbonate, magnesium carbonate, magnesium oxide, boron nitride, aluminum nitride, manganese nitride, aluminum borate, strontium carbonate, strontium titanate, calcium titanate, magnesium titanate, bismuth titanate, titanium oxide, zirconium oxide, barium titanate, barium zirconate, barium zirconate, calcium zirconate, zirconium phosphate, and zirconium tungstate phosphate. Among these, silicon dioxide is particularly preferred. Examples of silica include amorphous silica, fused silica, crystalline silica, synthetic silica, and hollow silica. Spherical silica is preferred. (D) The inorganic filler may be used alone or in combination of two or more at any ratio.

As commercially available products of (D) inorganic fillers, for example, there can be cited “UFP-30” manufactured by Denka Kagaku Kogyo Co., Ltd.; “SP60-05” and “SP507-05” manufactured by Nippon Steel & Sumitomo Metal Materials Corporation; “YC100C”, “YA050C”, “YA050C-MJE” and “YA010C” manufactured by ADMATECHS; “UFP-30” manufactured by DENKA Corporation; “Silfill NSS-3N”, “Silfill NSS-4N” and “Silfill NSS-5N” manufactured by TOKUYAMA; “SC2500SQ”, “SO-C4”, “SO-C2” and “SO-C1” manufactured by ADMATECHS; and “DAW-03” and “FB-105FD” manufactured by DENKA Corporation.

(D) From the viewpoint of significantly obtaining the effect of the present invention, the average particle size of the inorganic filler is preferably 0.01 μm or more, more preferably 0.05 μm or more, particularly preferably 0.1 μm or more, and preferably 5 μm or less, more preferably 2 μm or less, and particularly preferably 1 μm or less. (D) The average particle size of the inorganic filler can be measured by a laser diffraction/scattering method based on the Mie scattering theory. Specifically, a particle size distribution of the inorganic filler can be prepared on a volume basis using a laser diffraction scattering particle size distribution measuring device, and the median particle size can be measured as the average particle size. The measurement sample can be prepared by weighing 100 mg of the inorganic filler and 10 g of methyl ethyl ketone in a small bottle and dispersing them ultrasonically for 10 minutes. For the sample to be measured, a laser diffraction particle size distribution measuring device is used, and the wavelength of the light source used is set to blue and red. The particle size distribution of the inorganic filler based on volume is measured by a flow cell method, and the average particle size is calculated from the obtained particle size distribution as the median particle size. As an example of a laser diffraction particle size distribution measuring device, the "LA-960" manufactured by Horiba, Ltd. can be cited.

(D) The specific surface area of the inorganic filler is preferably 0.1 m ² /g or more, more preferably 0.5 m ² /g or more, particularly preferably 1 m ² /g or more, and particularly preferably 3 m ^{2 /g or more, and is preferably 100 m 2} /g or less, more preferably 70 m ² /g or less, particularly preferably 50 ^{m 2 /} g or less, and particularly preferably 40 m ² /g or less, from the viewpoint of significantly obtaining the effect of the present invention. The specific surface area of the inorganic filler is calculated by the BET method using a BET fully automatic specific surface area measuring device (Macsorb HM-1210 manufactured by MOUNTECH) by adsorbing nitrogen on the sample surface and using the BET multi-point method.

(D) The inorganic filler is preferably treated with a surface treatment agent from the viewpoint of improving moisture resistance and dispersibility. Examples of the surface treatment agent include fluorine-containing silane coupling agents, aminosilane-based coupling agents, epoxysilane-based coupling agents, butylsilane-based coupling agents, silane-based coupling agents, alkoxysilanes, organic silazane compounds, and titanium ester-based coupling agents. The surface treatment agent may be used alone or in combination of two or more.

Examples of commercially available surface treatment agents include "KBM-1003", "KBE-1003" (vinyl silane coupling agents); "KBM-303", "KBM-402", "KBM-403", "KBE-402", "KBE-403" (epoxy silane coupling agents); "KBM-1403" (styrene silane coupling agent); "KBM-1403" (styrene silane coupling agent); and "KBM-1403" (styrene silane coupling agent). -502", "KBM-503", "KBE-502", "KBE-503" (methacrylic silane coupling agent); "KBM-5103" (acrylic silane coupling agent); "KBM-602", "KBM-603", "KBM-903", "KBE-903", "KBE-9103P", "KBM-573", "KBM-575" (amino-based silane coupling agent); Silane coupling agent); "KBM-9659" (isocyanurate silane coupling agent); "KBE-585" (urea silane coupling agent); "KBM-802", "KBM-803" (heptyl silane coupling agent); "KBE-9007N" (isocyanate silane coupling agent); "X-12-967C" (anhydride silane coupling agent); "KBM-13", "KBM-22", "KBM-103", "KBE-13", "KBE-22", "KBE-103", "KBM-3033", "KBE-3033", "KBM-3063", "KBE-3063", "KBE-3083", "KBM-3103C", "KBM-3066", "KBM-7103" (non-silane non-silane coupled-alkoxysilane compounds), etc.

The degree of surface treatment by the surface treatment agent is preferably within a specific range from the viewpoint of improving the dispersibility of the (D) inorganic filler. Specifically, 100% by mass of the (D) inorganic filler is preferably surface treated with 0.2% by mass to 5% by mass of the surface treatment agent, more preferably 0.2% by mass to 3% by mass, and even more preferably 0.3% by mass to 2% by mass.

The degree of surface treatment by the surface treatment agent can be evaluated by the amount of carbon per unit surface area of the inorganic filler (D). From the perspective of improving the dispersibility of the inorganic filler, the amount of carbon per unit surface area of the inorganic filler is preferably 0.02 mg/ ^m2 or more, more preferably 0.1 mg/ ^m2 or more, and particularly preferably 0.2 mg/ ^m2 or more. On the other hand, from the perspective of preventing the increase in the melt viscosity of the resin composition or the melt viscosity of the sheet form, it is preferably 1.0 mg/ ^m2 or less, more preferably 0.8 mg/m2 or ^less , and particularly preferably 0.5 mg/ ^m2 or less.

(D) The amount of carbon per unit surface area of the inorganic filler can be measured after the surface-treated inorganic filler is washed with a solvent (e.g., methyl ethyl ketone (MEK)). Specifically, a sufficient amount of MEK as a solvent is added to the inorganic filler surface-treated with the surface treatment agent, and ultrasonically washed at 25°C for 5 minutes. After removing the supernatant and drying the non-volatile components, a carbon analyzer can be used to measure the amount of carbon per unit surface area of the inorganic filler. As a carbon analyzer, "EMIA-320V" manufactured by Horiba, Ltd. can be used.

The amount of the (D) inorganic filler in the resin composition is preferably 20 mass % or more, more preferably 30 mass % or more, particularly preferably 40 mass % or more, particularly preferably 50 mass % or more, and is preferably 90 mass % or less, more preferably 80 mass % or less, and particularly preferably 70 mass % or less, relative to 100 mass % of the non-volatile components in the resin composition.

The amount of the specific maleimide compound (A-1) is preferably 2% by mass or more, more preferably 5% by mass or more, particularly preferably 8% by mass or more, and is preferably 40% by mass or less, more preferably 30% by mass or less, particularly preferably 20% by mass or less, relative to 100% by mass of the inorganic filler (D). When the inorganic filler (D) is used in an amount satisfying such a relationship, the effect of the present invention can be significantly obtained.

The amount of the maleimide compound having the structure represented by formula (A1) is preferably 2% by mass or more, more preferably 5% by mass or more, particularly preferably 8% by mass or more, and preferably 40% by mass or less, more preferably 30% by mass or less, particularly preferably 20% by mass or less, relative to 100% by mass of the inorganic filler (D). When the inorganic filler (D) is used in an amount satisfying such a relationship, the effect of the present invention can be significantly obtained.

The amount of the (A) maleimide compound is preferably 2% by mass or more, more preferably 5% by mass or more, particularly preferably 10% by mass or more, and preferably 40% by mass or less, more preferably 30% by mass or less, particularly preferably 20% by mass or less, relative to 100% by mass of the (D) inorganic filler. When the (D) inorganic filler is used in an amount satisfying such a relationship, the effect of the present invention can be significantly obtained.

[6. (E) Optional hardener] The resin composition may further include (E) an optional hardener as an optional component in addition to the above components. However, (E) the optional hardener does not include (C) an active ester hardener. Examples of the optional hardener as the component (E) include phenol hardeners, naphthol hardeners, benzophenone hardeners, cyanate hardeners, carbodiimide hardeners, and acid anhydride hardeners. Among them, from the viewpoint of significantly obtaining the effect of the present invention, the optional hardener (E) is preferably any one or more of a phenol hardener, a naphthol hardener, a cyanate hardener, and a carbodiimide hardener, more preferably any one or more of a phenol hardener and a naphthol hardener, and particularly preferably a phenol hardener. The optional hardener (E) may be used alone or in combination of two or more at an arbitrary ratio.

As the phenolic hardener and the naphthol hardener, from the viewpoint of heat resistance and water resistance, a phenolic hardener having a novolac structure or a naphthol hardener having a novolac structure is preferred. From the viewpoint of adhesion to the conductive layer, a nitrogen-containing phenolic hardener is preferred, and a phenolic hardener containing a trioxane skeleton is more preferred.

Specific examples of the phenol-based hardener and the naphthol-based hardener include "MEH-7700", "MEH-7810", and "MEH-7851" manufactured by Meiwa Chemicals, "NHN", "CBN", and "GPH" manufactured by Nippon Kayaku Co., Ltd., "SN170", "SN-180", "SN-190", "SN-475", "SN-485", "SN-495", "SN-495V", "SN-375", and "SN-395" manufactured by Nippon Steel & Sumitomo Chemicals Corporation, and "TD-2090", "LA-7052", "LA-7054", "LA-1356", "LA3018-50P", and "EXB-9500" manufactured by DIC Corporation.

Specific examples of benzophenone-based hardeners include "JBZ-OP100D" and "ODA-BOZ" manufactured by JFE Chemical Co., Ltd., "HFB2006M" manufactured by Showa High Polymer Co., Ltd., and "P-d" and "F-a" manufactured by Shikoku Chemical Industries, Ltd.

Examples of the cyanate curing agent include bisphenol A dicyanate, polyphenol cyanate, oligo(3-methylene-1,5-phenylene cyanate), 4,4'-methylenebis(2,6-dimethylphenyl cyanate), 4,4'-ethylenediphenyl dicyanate, hexafluorobisphenol A dicyanate, 2,2-bis(4-cyanate)phenylpropane, 1,1-bis(4-cyanatephenylmethane) ), bifunctional cyanate resins such as bis(4-cyanate-3,5-dimethylphenyl)methane, 1,3-bis(4-cyanatephenyl-1-(methylethylidene))benzene, bis(4-cyanatephenyl)sulfide and bis(4-cyanatephenyl)ether, polyfunctional cyanate resins derived from phenol novolac and cresol novolac, prepolymers of these cyanate resins that are partially tri-ionized, etc. Specific examples of cyanate-based hardeners include "PT30" and "PT60" (phenol novolac-type multifunctional cyanate resins), "ULL-950S" (multifunctional cyanate resin), "BA230", and "BA230S75" (prepolymers obtained by partially or completely triturating bisphenol A dicyanate to form a trimer) manufactured by LONZA Japan Co., Ltd.

Specific examples of carbodiimide-based hardeners include "V-03" and "V-07" manufactured by Nisshinbo Chemical Co., Ltd.

Examples of the acid anhydride curing agent include those having one or more acid anhydride groups in one molecule, and preferably those having two or more acid anhydride groups in one molecule. Specific examples of the acid anhydride curing agent include phthalic anhydride, tetrahydrophthalic anhydride, hexahydrophthalic anhydride, methyltetrahydrophthalic anhydride, methylhexahydrophthalic anhydride, methylnadic anhydride, hydrogenated methylnadic anhydride, trialkyltetrahydrophthalic anhydride, dodecenylsuccinic anhydride, 5-(2,5-dioxotetrahydro-3-furanyl)-3-methyl-3-cyclohexene-1,2-dicarboxylic anhydride, trimellitic anhydride, pyromellitic anhydride, diphenyl Acid anhydrides of polymer type such as ketone tetracarboxylic dianhydride, biphenyl tetracarboxylic dianhydride, naphthalene tetracarboxylic dianhydride, oxydiphthalic dianhydride, 3,3'-4,4'-diphenylsulfonate tetracarboxylic dianhydride, 1,3,3a,4,5,9b-hexahydro-5-(tetrahydro-2,5-dioxo-3-furanyl)-naphtho[1,2-c]furan-1,3-dione, ethylene glycol bis(trimellitic anhydride), styrene-maleic acid resin obtained by copolymerization of styrene and maleic acid, etc. Examples of commercially available acid anhydride hardeners include "HNA-100" and "MH-700" manufactured by Shin Nippon Rika Co., Ltd.

The amount of the optional hardener (E) in the resin composition is not particularly limited, but is preferably 0.1% by mass or more, more preferably 0.2% by mass or more, particularly preferably 0.3% by mass or more, and is preferably 8% by mass or less, more preferably 5% by mass or less, particularly preferably 3% by mass or less, based on 100% by mass of the non-volatile components in the resin composition. When the amount of the optional hardener (E) is within the above range, the effect of the present invention can be significantly obtained.

The amount of the optional hardener (E) in the resin composition is not particularly limited, but is preferably 0.1% by mass or more, more preferably 0.5% by mass or more, particularly preferably 1% by mass or more, and is preferably 10% by mass or less, more preferably 8% by mass or less, particularly preferably 6% by mass or less, based on 100% by mass of the resin component in the resin composition. When the amount of the optional hardener (E) is within the above range, the effect of the present invention can be significantly obtained.

The ratio of the total number of active groups of (E) any curing agent to the total number of epoxy groups of (B) epoxy resin (active group/epoxy group) is preferably within a specific range. The aforementioned ratio (active group/epoxy group) is preferably 0.01 or more, more preferably 0.05 or more, particularly preferably 0.1 or more, and preferably 3 or less, more preferably 1 or less, particularly preferably 0.5 or less. The so-called "the total number of active groups of (E) any curing agent" is the value obtained by dividing the mass of the non-volatile components of (E) any curing agent present in the resin composition by the active group equivalent, and adding all the values together. When the aforementioned ratio (active group/epoxy group) is within the aforementioned range, the effect of the present invention can be significantly obtained.

[7. (F) Hardening accelerator] The resin composition may further contain (F) a hardening accelerator as an arbitrary component in addition to the above-mentioned components. Examples of the hardening accelerator include phosphorus-based hardening accelerators, urea-based hardening accelerators, guanidine-based hardening accelerators, imidazole-based hardening accelerators, metal-based hardening accelerators, and amine-based hardening accelerators. (F) The hardening accelerator may be used alone or in combination of two or more types at an arbitrary ratio.

Phosphorus-based hardening accelerators include, for example, tetrabutylphosphonium bromide, tetrabutylphosphonium chloride, tetrabutylphosphonium acetate, tetrabutylphosphonium decanoate, tetrabutylphosphonium laurate, di(tetrabutylphosphonium)benzene tetraoctanoate, tetrabutylphosphonium hydrohexahydrophthalate, tetrabutylphosphonium 2,6-bis[(2-hydroxy-5-methylphenyl)methyl]-4-methylphenol ester, di-tert-butylmethylphosphonium tetraphenylborate and the like; methyltriphenylphosphonium bromide, ethyltriphenylphosphonium bromide, propyltriphenylphosphonium bromide, butyltriphenylphosphonium bromide, benzyltriphenylphosphonium chloride, tetraphenylphosphonium bromide, p-tolyltriphenylphosphonium; Aromatic phosphonium salts such as triphenylphosphonium tetra-p-tolyl borate, tetraphenylphosphonium tetraphenyl borate, tetraphenylphosphonium tetra-p-tolyl borate, triphenylethylphosphonium tetraphenyl borate, tris(3-methylphenyl)ethylphosphonium tetraphenyl borate, tris(2-methoxyphenyl)ethylphosphonium tetraphenyl borate, (4-methylphenyl)triphenylphosphonium thiocyanate, tetraphenylphosphonium thiocyanate, butyltriphenylphosphonium thiocyanate; aromatic phosphine-borane complexes such as triphenylphosphine and triphenylborane; aromatic phosphine-quinone addition reactants such as triphenylphosphine-p-benzoquinone addition reactants; tributylphosphine, tri-t-butylphosphine, trioctylphosphine, di-t-butylphosphine aliphatic phosphines such as (2-butenyl)phosphine, di-tert-butyl(3-methyl-2-butenyl)phosphine, and tricyclohexylphosphine; dibutylphenylphosphine, di-tert-butylphenylphosphine, methyldiphenylphosphine, ethyldiphenylphosphine, butyldiphenylphosphine, diphenylcyclohexylphosphine, triphenylphosphine, tri-o-tolylphosphine, tri-m-tolylphosphine, tri-p-tolylphosphine, tris(4-ethylphenyl)phosphine, tris(4-propylphenyl)phosphine, tris(4-isopropylphenyl)phosphine, tris(4-butylphenyl)phosphine, tris(4-tert-butylphenyl)phosphine, tris(2,4-dimethylphenyl)phosphine, tris(2,5-dimethylphenyl)phosphine, tris(2,6- Aromatic phosphines such as tris(2,4-dimethylphenyl)phosphine, tris(3,5-dimethylphenyl)phosphine, tris(2,4,6-trimethylphenyl)phosphine, tris(2,6-dimethyl-4-ethoxyphenyl)phosphine, tris(2-methoxyphenyl)phosphine, tris(4-methoxyphenyl)phosphine, tris(4-ethoxyphenyl)phosphine, tris(4-tert-butoxyphenyl)phosphine, diphenyl-2-pyridylphosphine, 1,2-bis(diphenylphosphino)ethane, 1,3-bis(diphenylphosphino)propane, 1,4-bis(diphenylphosphino)butane, 1,2-bis(diphenylphosphino)acetylene, and 2,2'-bis(diphenylphosphino)diphenyl ether.

Examples of the urea-based hardening accelerator include 1,1-dimethylurea; aliphatic dimethylureas such as 1,1,3-trimethylurea, 3-ethyl-1,1-dimethylurea, 3-cyclohexyl-1,1-dimethylurea, and 3-cyclooctyl-1,1-dimethylurea; 3-phenyl-1,1-dimethylurea, 3-(4-chlorophenyl)-1,1-dimethylurea, 3-(3,4-dichlorophenyl)-1,1-dimethylurea, 3-(3-chloro-4-methylphenyl)-1,1-dimethylurea, 3-(2-methylphenyl)-1,1-dimethylurea, 3-(4-methylphenyl)-1,1-dimethylurea, 3-(3,4-dimethylphenyl)-1,1 -dimethylurea, 3-(4-isopropylphenyl)-1,1-dimethylurea, 3-(4-methoxyphenyl)-1,1-dimethylurea, 3-(4-nitrophenyl)-1,1-dimethylurea, 3-[4-(4-methoxyphenoxy)phenyl]-1,1-dimethylurea, 3-[4-(4-chlorophenoxy)phenyl]-1,1-dimethylurea, 3-[3-(trifluoromethyl)phenyl]-1,1-dimethylurea, N,N-(1,4-phenylene)bis(N’,N’-dimethylurea), N,N-(4-methyl-1,3-phenylene)bis(N’,N’-dimethylurea) [toluenebisdimethylurea] and the like.

Examples of the guanidine-based hardening accelerator include cyanoguanidine, 1-methylguanidine, 1-ethylguanidine, 1-cyclohexylguanidine, 1-phenylguanidine, 1-(o-tolyl)guanidine, dimethylguanidine, diphenylguanidine, trimethylguanidine, tetramethylguanidine, pentamethylguanidine, 1,5,7-triazabicyclo[4.4.0]dec-5-ene, 7-methyl-1,5,7-triazabicyclo[4.4.0]dec-5-ene, 1-methylbiguanidine, 1-ethylbiguanidine, 1-n-butylbiguanidine, 1-n-octadecylbiguanidine, 1,1-dimethylbiguanidine, 1,1-diethylbiguanidine, 1-cyclohexylbiguanidine, 1-allylbiguanidine, 1-phenylbiguanidine, and 1-(o-tolyl)biguanidine.

Examples of the imidazole-based hardening accelerator include 2-methylimidazole, 2-undecylimidazole, 2-heptadecylimidazole, 1,2-dimethylimidazole, 2-ethyl-4-methylimidazole, 1,2-dimethylimidazole, 2-ethyl-4-methylimidazole, 2-phenylimidazole, 2-phenyl-4-methylimidazole, 1-benzyl-2-methylimidazole, 1-benzyl-2-phenylimidazole, 1-cyanoethyl-2-methylimidazole, 1-cyanoethyl-2-undecylimidazole, 1-cyanoethyl-2-ethyl-4-methylimidazole, 1-cyanoethyl-2-phenylimidazole, 1-cyanoethyl-2-undecylimidazole, 1-cyanoethyl-2-ethyl-4-methylimidazole, 1-cyanoethyl-2-phenylimidazole, 1-cyanoethyl-2-undecylimidazole trimellitate, 1-cyanoethyl-2-phenylimidazole trimellitate, 2,4-diamino-6-[2'-methylimidazolyl-(1')]-ethyl- s-triazine, 2,4-diamino-6-[2'-undecylimidazolyl-(1')]-ethyl-s-triazine, 2,4-diamino-6-[2'-ethyl-4'-methylimidazolyl-(1')]-ethyl-s-triazine, 2,4-diamino-6-[2'-methylimidazolyl-(1')]-ethyl-s-triazine isocyanuric acid adduct, 2-phenylimidazolyl isocyanuric acid Imidazole compounds such as cyanuric acid adducts, 2-phenyl-4,5-dihydroxymethylimidazole, 2-phenyl-4-methyl-5-hydroxymethylimidazole, 2,3-dihydro-1H-pyrrolo[1,2-a]benzimidazole, 1-dodecyl-2-methyl-3-benzylimidazolium chloride, 2-methylimidazoline, 2-phenylimidazoline, and adducts of imidazole compounds and epoxy resins. As imidazole-based hardening accelerators, commercially available products can be used, for example, "1B2PZ", "2MZA-PW", "2PHZ-PW" manufactured by Shikoku Chemical Industries, Ltd., and "P200-H50" manufactured by Mitsubishi Chemical Corporation.

Examples of the metal hardening accelerator include organic metal complexes or organic metal salts of metals such as cobalt, copper, zinc, iron, nickel, manganese, and tin. Specific examples of the organic metal complex include organic cobalt complexes such as cobalt (II) acetylacetonate and cobalt (III) acetylacetonate, organic copper complexes such as copper (II) acetylacetonate, organic zinc complexes such as zinc (II) acetylacetonate, organic iron complexes such as iron (III) acetylacetonate, organic nickel complexes such as nickel (II) acetylacetonate, and organic manganese complexes such as manganese (II) acetylacetonate. Examples of the organic metal salt include zinc octylate, tin octylate, zinc cycloalkanoate, cobalt cycloalkanoate, tin stearate, zinc stearate, and the like.

Examples of the amine-based hardening accelerator include trialkylamines such as triethylamine and tributylamine, 4-dimethylaminopyridine, benzyldimethylamine, 2,4,6-tris(dimethylaminomethyl)phenol, and 1,8-diazabicyclo(5,4,0)-undecene. Amine-based hardening accelerators that can be used include commercially available products, such as "MY-25" manufactured by Ajinomoto Precision Technology Co., Ltd.

The amount of the (F) hardening accelerator in the resin composition is not particularly limited, but is preferably 0.001% by mass or more, more preferably 0.01% by mass or more, particularly preferably 0.05% by mass or more, and preferably 15% by mass or less, more preferably 10% by mass or less, particularly preferably 5% by mass or less, relative to 100% by mass of the non-volatile components in the resin composition. When the amount of the (F) hardening accelerator is within the above range, the effect of the present invention can be significantly obtained.

The amount of the (F) hardening accelerator in the resin composition is not particularly limited, but is preferably 0.001% by mass or more, more preferably 0.01% by mass or more, particularly preferably 0.1% by mass or more, and preferably 15% by mass or less, more preferably 10% by mass or less, particularly preferably 5% by mass or less, relative to 100% by mass of the resin component in the resin composition. When the amount of the (F) hardening accelerator is within the above range, the effect of the present invention can be significantly obtained.

[8. (G) Solvent] The resin composition may further contain (G) solvent as an arbitrary component in addition to the above-mentioned components. The solvent is usually a volatile component, and an organic solvent may be used. Examples of (G) solvents include ketone solvents such as acetone, methyl ethyl ketone (MEK) and cyclohexanone; acetate solvents such as ethyl acetate, butyl acetate, cellosol acetate, propylene glycol monomethyl ether acetate and carbitol acetate; carbitol solvents such as cellosol and butyl carbitol; aromatic hydrocarbon solvents such as toluene and xylene; amide solvents such as dimethylformamide, dimethylacetamide (DMAc) and N-methylpyrrolidone, etc. (G) The solvent may be used alone or in combination of two or more kinds at any ratio.

The amount of the (G) solvent is not particularly limited. The amount of the (G) solvent is relative to 100% by mass of all components in the resin composition, for example, it can be 60% by mass or less, 40% by mass or less, 30% by mass or less, 20% by mass or less, 15% by mass or less, 10% by mass or less, etc.

[9. Other components] The resin composition may further contain any additives as arbitrary components in addition to the above components. Examples of such additives include thermosetting resins, organic fillers, thickeners, defoamers, leveling agents, adhesion promoters, flame retardants, etc. These may be used alone or in combination of two or more at any ratio.

[10. Method for producing resin composition] The resin composition can be produced, for example, by mixing the above-mentioned components in any order. In addition, during the mixing of the components, heating and/or cooling can be performed by appropriately adjusting the temperature. In addition, during or after the mixing of the components, stirring can be performed using a stirring device such as a mixer to uniformly disperse the components. Furthermore, the resin composition can be subjected to a defoaming treatment as required.

[11. Properties of resin composition] The above resin composition can produce a hardened material with a low dielectric tangent and a high glass transition temperature.

For example, the dielectric tangent Df of the cured product obtained by curing the resin composition under the conditions described in the embodiments described below is preferably 0.010 or less, more preferably 0.005 or less, and particularly preferably 0.004 or less. The lower limit of the dielectric tangent Df of the cured product is not particularly limited, but can be 0.001 or more. The dielectric tangent of the cured product can be measured by the method described in the embodiments.

For example, the glass transition temperature Tg of the cured product obtained by curing the resin composition under the conditions described in the embodiments described below is preferably 130° C. or higher, more preferably 140° C. or higher, and particularly preferably 150° C. or higher. The upper limit of the glass transition temperature Tg of the cured product is not particularly limited, but may be 260° C. or lower.

The cured product of the resin composition may generally have a small dielectric constant. For example, the dielectric constant Dk of the cured product obtained by curing the resin composition under the conditions described in the embodiments described below is preferably 3.5 or less, more preferably 3.2 or less, and particularly preferably 3.0 or less. The lower limit of the dielectric constant of the cured product is not particularly limited, but may be, for example, 2.0 or more. The dielectric constant of the cured product can be measured by the method described in the embodiments.

When the insulating layer is formed by the hardened material of the resin composition, the surface roughness of the insulating layer after the roughening treatment can usually be reduced. For example, when the insulating layer is formed and roughened by the method described in the embodiments described below, the arithmetic average roughness Ra of the surface of the insulating layer is preferably less than 200nm, more preferably less than 100nm, and particularly preferably less than 70nm. The lower limit of the arithmetic average roughness Ra is not particularly limited, but can be, for example, more than 10nm. The arithmetic average roughness Ra of the surface of the insulating layer can be measured by the method described in the embodiments.

Furthermore, when an insulating layer is formed by hardening the resin composition and a conductive layer is formed on the insulating layer by plating, the plating peel strength, which is the adhesion strength between the insulating layer and the conductive layer, can be increased. For example, when the insulating layer and the conductive layer are formed by the method described in the embodiment described later, the plating peel strength between the insulating layer and the conductive layer is preferably 0.3 kgf/cm or more, more preferably 0.4 kgf/cm or more, and particularly preferably 0.5 kgf/cm or more. The upper limit of the plating peel strength is not particularly limited, but can be, for example, 2.0 kgf/cm or less. The plating peel strength between the insulating layer and the conductive layer can be measured by the method described in the embodiments.

[12. Use of resin composition] The resin composition of one embodiment of the present invention is a resin composition suitable for insulating purposes, and is particularly suitable as a resin composition for forming an insulating layer. Therefore, for example, the resin composition is suitable as a resin composition for forming an insulating layer of a printed wiring board (resin composition for forming an insulating layer of a printed wiring board). In addition, the resin composition is suitable as a resin composition for forming a conductive layer (including a redistribution layer) formed on the conductive layer to form the conductive layer (resin composition for forming an insulating layer for forming a conductive layer). Furthermore, the resin composition can be widely used in applications where the resin composition can be used, such as resin sheets, prepreg and other sheet-shaped lamination materials, solder resists, underfill materials, die attach materials, semiconductor sealing materials, via embedding resins, and component embedding resins.

Furthermore, for example, when a semiconductor chip package is manufactured through the following steps (1) to (6), the resin composition of the present embodiment can also be suitable as a resin composition for a redistribution forming layer (resin composition for forming a redistribution forming layer) used to form an insulating layer of a redistribution layer and a resin composition for sealing a semiconductor chip (resin composition for sealing a semiconductor chip). When manufacturing a semiconductor chip package, a redistribution layer can be further formed on the sealing layer. (1) a step of laminating a temporary fixing film on a substrate, (2) a step of temporarily fixing a semiconductor chip on the temporary fixing film, (3) a step of forming a sealing layer on the semiconductor chip, (4) a step of peeling the substrate and the temporary fixing film from the semiconductor chip, (5) a step of forming a redistribution layer as an insulating layer on the surface of the semiconductor chip after the substrate and the temporary fixing film are peeled off, and (6) a step of forming a redistribution layer as a conductive layer on the redistribution layer.

The above resin composition can also be used in the case where the printed wiring board is a circuit board with built-in parts.

[13. Laminated sheet material] The resin composition of one embodiment of the present invention can be used by coating in a varnish state, but it is industrially preferred to use it in the form of a laminated sheet material containing the resin composition. The laminated sheet material is preferably a resin sheet or prepreg as shown below.

The resin sheet comprises a support and a resin composition layer formed on the support using the resin composition.

The thickness of the resin composition layer is preferably 50 μm or less, more preferably 40 μm or less, and particularly preferably 30 μm or less, from the viewpoint of thinning the printed wiring board and providing a cured product having excellent insulation even if the cured product of the resin composition is a thin film. The lower limit of the thickness of the resin composition layer is not particularly limited, but may be, for example, 3 μm or more, 5 μm or more, etc.

As the support, for example, a film made of a plastic material, a metal foil, and a release paper can be cited, and a film made of a plastic material and a metal foil are preferred.

When a film made of a plastic material is used as a support, examples of the plastic material include polyesters such as polyethylene terephthalate (hereinafter also referred to as "PET") and polyethylene naphthalate (hereinafter also referred to as "PEN"), polycarbonate (hereinafter also referred to as "PC"), acrylics such as polymethyl methacrylate (PMMA), cyclic polyolefins, triacetyl cellulose (TAC), polyether sulfide (PES), polyether ketone, polyimide, etc. Among them, polyethylene terephthalate and polyethylene naphthalate are preferred, and inexpensive polyethylene terephthalate is particularly preferred.

When a metal foil is used as a support, examples of the metal foil include copper foil and aluminum foil, and copper foil is preferred. The copper foil may be a foil made of copper alone or an alloy of copper and other metals (such as tin, chromium, silver, magnesium, nickel, zirconium, silicon, titanium, etc.).

The surface of the support body that is bonded to the resin composition layer may be subjected to surface treatments such as matte treatment, corona treatment, and antistatic treatment.

Furthermore, as the support, a support with a release layer having a release layer on the surface bonded to the resin composition layer may be used. As a release agent for the release layer of the support with a release layer, for example, one or more release agents selected from the group consisting of alkyd resins, polyolefin resins, urethane resins, and silicone resins may be cited. The support body with a release layer can be a commercially available product, for example, PET film having a release layer with an alkyd resin release agent as the main component, such as "SK-1", "AL-5", and "AL-7" manufactured by LINTEC, "Lumirror T60" manufactured by Toray, "Purex" manufactured by Teijin, and "Unipeel" manufactured by UNITIKA.

The thickness of the support is not particularly limited, but is preferably in the range of 5 μm to 75 μm, more preferably in the range of 10 μm to 60 μm. Furthermore, when a support with a release layer is used, the thickness of the entire support with a release layer is preferably in the above range.

In one embodiment, the resin sheet may further include an arbitrary layer as needed. As the arbitrary layer, for example, a protective film that conforms to the support and is provided on the surface of the resin composition layer that is not bonded to the support (i.e., the surface on the opposite side of the support). The thickness of the protective film is not particularly limited, but is, for example, 1 μm to 40 μm. By laminating the protective film, dust and the like can be prevented from adhering to or damaging the surface of the resin composition layer.

The resin sheet can be produced, for example, by preparing a resin varnish in which a resin composition is dissolved in a solvent, applying the resin varnish on a support using a coating device such as a die coater, and drying the resin varnish to form a resin composition layer. As the solvent, for example, the same as those explained as the component (G) that can be contained in the resin composition can be cited. The solvent can be used alone or in combination of two or more types in any ratio.

Drying can be carried out by heating, hot air blowing, etc. There is no particular limitation on the drying conditions, but the resin composition layer is dried in such a manner that the content of the organic solvent is 10% by mass or less, preferably 5% by mass or less. Although it also varies with the boiling point of the organic solvent in the resin varnish, for example, when a resin varnish containing 30% to 60% by mass of an organic solvent is used, the resin composition layer can be formed by drying at 50°C to 150°C for 1 minute to 10 minutes.

The resin sheet can be stored by being rolled into a roll. If the resin sheet has a protective film, it can be used by peeling off the protective film.

In one embodiment, the prepreg is formed by impregnating a sheet-like fiber substrate with a resin composition.

The sheet-like fiber substrate used for the prepreg is not particularly limited, and examples thereof include glass cloth, polyaramid non-woven fabric, liquid crystal polymer non-woven fabric, etc. From the perspective of thinning the printed wiring board, the thickness of the sheet-like fiber substrate is preferably 50 μm or less, more preferably 40 μm or less, particularly preferably 30 μm or less, and particularly preferably 20 μm or less. The lower limit of the thickness of the sheet-like fiber substrate is not particularly limited, but is usually 10 μm or more.

The prepreg can be produced by a well-known method such as a hot melt method or a solvent method.

The thickness of the prepreg can be set to the same range as that of the resin composition layer in the above-mentioned resin sheet.

[14. Printed wiring board] A printed wiring board according to one embodiment of the present invention includes an insulating layer formed of a cured product obtained by curing the above-mentioned resin composition.

A printed wiring board can be manufactured, for example, using the above-mentioned resin sheet by a method comprising the following steps (I) and (II). (I) A step of laminating the resin sheet on the inner substrate in such a manner that the resin composition layer of the resin sheet is bonded to the inner substrate, (II) A step of hardening the resin composition layer to form an insulating layer.

The "inner layer substrate" used in step (I) is a component that becomes the substrate of the printed wiring board, and examples thereof include glass epoxy substrates, metal substrates, polyester substrates, polyimide substrates, BT resin substrates, and thermosetting polyphenylene ether substrates. In addition, the substrate may have a conductive layer on one or both sides thereof, and the conductive layer may be patterned. An inner layer substrate having a conductive layer formed on one or both sides of a substrate is sometimes referred to as an "inner layer circuit substrate." In addition, when manufacturing a printed wiring board, an intermediate product that forms an insulating layer and/or a conductive layer is also included in the "inner layer substrate" referred to in the present invention. When the printed wiring board is a circuit board with built-in components, an inner layer substrate with built-in components can be used.

The inner substrate and the resin sheet can be laminated, for example, by heating and pressing the resin sheet to the inner substrate from the support body side. As a member for heating and pressing the resin sheet to the inner substrate (hereinafter, also referred to as a "heating and pressing member"), for example, a heated metal plate (SUS end plate, etc.) or a metal roller (SUS roller) can be cited. Moreover, it is preferred not to press the heating and pressing member directly on the resin sheet, but to press it through an elastic material such as heat-resistant rubber in a manner that the resin sheet fully follows the surface unevenness of the inner substrate.

The lamination of the inner substrate and the resin sheet can be performed by vacuum lamination. In the vacuum lamination, the heating and pressing temperature is preferably 60°C to 160°C, more preferably 80°C to 140°C, the heating and pressing pressure is preferably 0.098MPa to 1.77MPa, more preferably 0.29MPa to 1.47MPa, and the heating and pressing time is preferably 20 seconds to 400 seconds, more preferably 30 seconds to 300 seconds. Lamination can be preferably performed under reduced pressure conditions with a pressure of less than 26.7hPa.

Lamination can be performed by a commercially available vacuum laminator. Examples of commercially available vacuum laminators include a vacuum pressure laminator manufactured by Meiki Seisakusho Co., Ltd., a vacuum applicator manufactured by NIKKO Materials Co., Ltd., and a batch vacuum pressure laminator.

After lamination, the laminated resin sheets can be smoothed by, for example, applying pressure to the heat-pressing member from the side of the support under atmospheric pressure. The pressurizing conditions for the smoothing treatment can be set to the same conditions as the heat-pressing conditions for the above-mentioned lamination. The smoothing treatment can be performed by a commercially available laminator. Moreover, the lamination and smoothing treatment can also be performed continuously using the above-mentioned commercially available vacuum laminator.

The support may be removed between step (I) and step (II), or after step (II).

In step (II), the resin composition layer is cured to form an insulating layer composed of a cured product of the resin composition. The curing conditions of the resin composition layer are not particularly limited, and the conditions used when forming an insulating layer of a printed wiring board can be used. Generally, the curing of the resin composition layer can be performed by thermal curing.

For example, although the heat curing conditions of the resin composition layer vary depending on the type of the resin composition, in one embodiment, the curing temperature is preferably 120° C. to 240° C., more preferably 150° C. to 220° C., and particularly preferably 170° C. to 210° C. The curing time is preferably 5 minutes to 120 minutes, more preferably 10 minutes to 100 minutes, and particularly preferably 15 minutes to 100 minutes.

Before the resin composition layer is heat-hardened, the resin composition layer may be preheated at a temperature lower than the hardening temperature. For example, before the resin composition layer is heat-hardened, the resin composition layer may be preheated at a temperature of 50°C to 120°C, preferably 60°C to 115°C, more preferably 70°C to 110°C, for more than 5 minutes, preferably 5 minutes to 150 minutes, more preferably 15 minutes to 120 minutes, and particularly preferably 15 minutes to 100 minutes.

When manufacturing a printed wiring board, the step (III) of opening holes in the insulating layer, the step (IV) of roughening the insulating layer, and the step (V) of forming a conductive layer may be further performed. When the support is removed after the step (II), the removal of the support may be performed between the step (II) and the step (III), between the step (III) and the step (IV), or between the step (IV) and the step (V). Furthermore, the formation of the insulating layer and the conductive layer in the steps (I) to (V) may be repeated as needed to form a multi-layer wiring board.

In other embodiments, a printed wiring board can be manufactured using the above-mentioned prepreg. The manufacturing method is basically the same as that using a resin sheet.

Step (III) is a step of drilling holes in the insulating layer, thereby forming holes such as through holes and through holes in the insulating layer. Step (III) can be performed, for example, using a drilling machine, laser, plasma, etc., depending on the composition of the resin composition used to form the insulating layer. The size or shape of the hole can be appropriately determined according to the design of the printed wiring board.

Step (IV) is a step of roughening the insulating layer. Usually, in this step (IV), the scum is also removed. The order and conditions of the roughening treatment are not particularly limited. For example, the insulating layer can be roughened by carrying out swelling treatment with a swelling liquid, roughening treatment with an oxidizing agent, and neutralization treatment with a neutralizing liquid in this order.

As the swelling liquid used for the roughening treatment, for example, an alkaline solution, a surfactant solution, etc. can be cited, and the alkaline solution is preferred. As the alkaline solution, a sodium hydroxide solution and a potassium hydroxide solution are more preferred. As commercially available swelling liquid, for example, "Swelling Dip Securiganth P" and "Swelling Dip Securiganth SBU" manufactured by ATOTECH Japan Co., Ltd. can be cited. The swelling treatment of the swelling liquid is not particularly limited, and for example, it can be performed by immersing the insulating layer in a swelling liquid at 30°C to 90°C for 1 minute to 20 minutes. From the viewpoint of suppressing the swelling of the resin of the insulating layer to an appropriate degree, it is preferred to immerse the insulating layer in a swelling liquid at 40°C to 80°C for 5 minutes to 15 minutes.

As an oxidizing agent used for the roughening treatment, for example, an alkaline permanganic acid solution in which potassium permanganate or sodium permanganate is dissolved in an aqueous solution of sodium hydroxide can be cited. The roughening treatment with an oxidizing agent such as an alkaline permanganic acid solution is preferably carried out by immersing the insulating layer in the oxidizing agent solution heated to 60°C to 100°C for 10 minutes to 30 minutes. In addition, the concentration of permanganate in the alkaline permanganic acid solution is preferably 5% by mass to 10% by mass. As a commercially available oxidizing agent, for example, alkaline permanganic acid solutions such as "Concentrate Compact CP" and "Dosing Solution Securiganth P" manufactured by ATOTECH Japan Co., Ltd. can be cited.

As the neutralizing solution used for the roughening treatment, an acidic aqueous solution is preferred. As a commercially available product, for example, "Reduction Solution Securigant P" manufactured by ATOTECH Japan Co., Ltd. can be cited. The treatment with the neutralizing solution can be performed by immersing the roughening treatment surface treated with an oxidizing agent in a neutralizing solution at 30°C to 80°C for 5 to 30 minutes. From the perspective of workability, etc., it is more preferred to immerse the roughening treatment object treated with an oxidizing agent in a neutralizing solution at 40°C to 70°C for 5 to 20 minutes.

In one embodiment, the arithmetic average roughness Ra of the insulating layer surface after the roughening treatment is preferably less than 500nm, more preferably less than 400nm, and particularly preferably less than 300nm. There is no special limitation on the lower limit, for example, it can be set to more than 1nm, more than 2nm, etc. In addition, the root mean square roughness (Rq) of the insulating layer surface after the roughening treatment is preferably less than 500nm, more preferably less than 400nm, and particularly preferably less than 300nm. There is no special limitation on the lower limit, for example, it can be set to more than 1nm, more than 2nm, etc. The arithmetic average roughness (Ra) and root mean square roughness (Rq) of the insulating layer surface can be measured using a non-contact surface roughness meter.

Step (V) is a step of forming a conductive layer, and the conductive layer is formed on the insulating layer. The conductive material used for the conductive layer is not particularly limited. In a suitable embodiment, the conductive layer includes one or more metals selected from the group consisting of gold, platinum, palladium, silver, copper, aluminum, cobalt, chromium, zinc, nickel, titanium, tungsten, iron, tin and indium. The conductive layer can be a single metal layer or an alloy layer. As an alloy layer, for example, a layer formed by an alloy of two or more metals selected from the above group (for example, nickel-chromium alloy, copper-nickel alloy and copper-titanium alloy) can be cited. Among them, from the viewpoint of versatility of conductor layer formation, cost, ease of patterning, etc., a single metal layer of chromium, nickel, titanium, aluminum, zinc, gold, palladium, silver or copper, or an alloy layer of nickel-chromium alloy, copper-nickel alloy, or copper-titanium alloy is preferred, a single metal layer of chromium, nickel, titanium, aluminum, zinc, gold, palladium, silver or copper, or an alloy layer of nickel-chromium alloy is more preferred, and a single metal layer of copper is particularly preferred.

The conductive layer may be a single layer structure or a composite structure of two or more single metal layers or alloy layers made of different types of metals or alloys. When the conductive layer is a composite structure, the layer in contact with the insulating layer is preferably a single metal layer of chromium, zinc or titanium, or an alloy layer of nickel-chromium alloy.

The thickness of the conductor layer depends on the desired design of the printed wiring board, but is generally 3μm to 35μm, preferably 5μm to 30μm.

The conductive layer is preferably formed by plating. For example, a conductive layer having a desired wiring pattern can be formed by plating on the surface of the insulating layer by a semi-additive method, a full-additive method, etc. From the perspective of simplicity of manufacturing, it is preferably formed by a semi-additive method. The following shows an example of forming a conductive layer by a semi-additive method.

A plating seed layer is formed on the surface of the insulating layer by electroless plating. Then, a mask pattern is formed on the formed plating seed layer to expose a portion of the plating seed layer corresponding to the desired wiring pattern. After a metal layer is formed on the exposed plating seed layer by electrolytic plating, the mask pattern is removed. Then, the unnecessary plating seed layer can be removed by etching or the like to form a conductor layer having the desired wiring pattern.

[15. Semiconductor device] A semiconductor device according to one embodiment of the present invention includes the above-mentioned printed wiring board. This semiconductor device can be manufactured using the above-mentioned printed wiring board.

As semiconductor devices, various semiconductor devices used in electrical products (such as computers, mobile phones, digital cameras, and televisions) and transportation vehicles (such as motorcycles, cars, trains, ships, and aircrafts) can be cited. [Example]

The following examples are shown to more specifically illustrate the present invention, but the present invention is not limited to the following examples. In the following description, "parts" and "%" indicating quantity mean "parts by mass" and "% by mass" respectively unless otherwise specified. In addition, the operations described below are performed under normal temperature and pressure unless otherwise specified.

[Preparation of maleimide compound] A MEK solution (non-volatile component 70 mass %) of maleimide compound _A1 synthesized by the method described in Synthesis Example 1 of Japan Invention Patent Publication No. 2020-500211 was prepared. This maleimide compound _A1 has a structure shown in the following formula.

When the FD-MS spectrum of the maleimide compound _A1 was measured, peaks of M+=560, 718 and 876 were confirmed. These peaks correspond to the cases where _n1 is 0, 1 and 2, respectively. In addition, when the value of the repeating unit number _n1 of the indane skeleton part was calculated from the number average molecular weight by GPC analysis of the maleimide compound _A1 , _n1 =1.47, and the molecular weight distribution (Mw/Mn)=1.81. Furthermore, in the total amount of 100 area % of the maleimide compound _A1 , the content ratio of the maleimide compound whose average repeating unit number _n1 is 0 is 26.5 area %.

The FD-MS spectrum of the maleimide compound _A1 is measured using the following measuring device and measuring conditions. (FD-MS spectrum measuring device and measuring conditions) Measuring device: JMS-T100GC AccuTOF Measuring conditions Measuring range: m/z = 4.00 to 2000.00 Rate of change: 51.2 mA/min Final current value: 45 mA Cathode voltage: -10 kV Recording interval: 0.07 sec

The GPC of the maleimide compound _A1 is measured using the following measuring apparatus and measuring conditions. Measuring apparatus: "HLC-8320 GPC" manufactured by Tosoh Corporation Column: Guard column "HXL-L" manufactured by Tosoh Corporation, "TSK-GEL G2000HXL" manufactured by Tosoh Corporation, "TSK-GEL G2000HXL" manufactured by Tosoh Corporation, "TSK-GEL G3000HXL" manufactured by Tosoh Corporation, and "TSK-GEL G4000HXL" manufactured by Tosoh Corporation Detector: RI (differential refractometer) Data processing: "GPC Workstation EcoSEC-WorkStation" manufactured by Tosoh Corporation Measurement conditions: Column temperature 40°C Developing solvent Tetrahydrofuran Flow rate 1.0 ml/min Standard: According to the measurement manual of the aforementioned "GPC Workstation EcoSEC-WorkStation", the molecular weight uses known monodisperse polystyrene. Sample: A tetrahydrofuran solution (50 μl) containing 1.0 mass % of the nonvolatile component of the maleimide compound was filtered through a microfilter.

The molecular weight distribution (weight average molecular weight (Mw)/number average molecular weight (Mn)) of the maleimide compound _A1 and the average repeating unit number " _n1 " of the indane skeleton contributing to the maleimide compound are calculated from the GPC chart obtained by the aforementioned GPC measurement. The average repeating unit number " _n1 " is calculated from the number average molecular weight (Mn). Specifically, for compounds where _n1 is 0 to 4, the theoretical molecular weight and the molecular weight measured by GPC are plotted on a scatter plot and an approximate straight line is drawn. Then, from the point indicated by the measured value Mn (1) on the straight line, the number average molecular weight (Mn) is calculated, and the average repeating unit " _n1 " is further calculated. Furthermore, based on the results of GPC measurement, the content ratio (area %) of the maleimide compound _A1 in which the average repeating unit number _n1 is 0 is calculated in the total amount of 100 area % of the maleimide compound A1. For details, please refer to the Japanese Invention Patent Publication No. 2020-500211.

[Example 1] 20 parts of the maleimide compound _A1 (solution containing 70% by mass of non-volatile components), 10 parts of a liquid epoxy resin containing a naphthalene skeleton ("HP-4032-SS" manufactured by DIC Corporation, epoxy equivalent 144 g/eq.), 30 parts of an active ester curing agent containing a dicyclopentadiene-type diphenol structure ("HPC-8000-65T" manufactured by DIC Corporation, toluene solution containing 65% by mass of non-volatile components, active ester group equivalent 223 g/eq.), and spherical silica ("SO-C2" manufactured by ADMATECHS Corporation, average particle size 0.5 μm, specific surface area 5.8 ^m2) surface-treated with an inorganic filler (amine-based alkoxysilane compound ("KBM573" manufactured by Shin-Etsu Chemical Co., Ltd.) were mixed. /g) and 0.5 parts of a curing accelerator (imidazole compound "1B2PZ" manufactured by Shikoku Chemical Co., Ltd.), and they were uniformly dispersed using a high-speed rotary mixer to obtain a resin varnish.

As a support, a polyethylene terephthalate film ("AL5" manufactured by LINTEC, thickness 38μm) with a release layer was used. The resin varnish was evenly applied on the release layer of the support so that the thickness of the resin composition layer after drying was 40μm. Then, the resin varnish was dried at 80℃ to 100℃ (average 90℃) for 4 minutes to obtain a resin sheet containing the support and the resin composition layer.

[Example 2] Instead of the active ester curing agent containing a dicyclopentadiene-type diphenol structure ("HPC-8000-65T" manufactured by DIC Corporation), 30 parts of an active ester compound containing a naphthalene structure ("HPC-8150-62T" manufactured by DIC Corporation, a toluene solution containing 62% by mass of non-volatile components, an active ester group equivalent of 229 g/eq.) were used. The resin sheet was produced in the same manner as in Example 1 except for the above matters.

[Example 3] The amount of maleimide compound _A1 (solution with 70% non-volatile content by mass) was changed from 20 parts to 15 parts. In addition, 30 parts of active ester compound containing naphthalene structure ("HPC-8150-62T" manufactured by DIC, toluene solution with 62% non-volatile content by mass, active ester group equivalent 229 g/eq.) were used instead of active ester curing agent containing dicyclopentadiene type diphenol structure ("HPC-8000-65T" manufactured by DIC), and 5 parts of biphenyl aralkyl type maleimide compound ("MIR-3000-70MT" manufactured by Nippon Kayaku Co., Ltd., maleimide group equivalent: 275 g/eq., MEK/toluene mixed solution with 70% non-volatile content) were added to the resin composition. The resin sheet was produced in the same manner as in Example 1 except for the above matters.

[Example 4] The amount of maleimide compound _A1 (solution containing 70% by mass of nonvolatile components) was changed from 20 parts to 18 parts. In addition, 30 parts of active ester compound containing naphthalene structure ("HPC-8150-62T" manufactured by DIC, toluene solution containing 62% by mass of nonvolatile components, active ester group equivalent 229 g/eq.) were used instead of active ester curing agent containing dicyclopentadiene-type diphenol structure ("HPC-8000-65T" manufactured by DIC). Furthermore, 2 parts of liquid aliphatic maleimide compound ("BMI-1500" manufactured by Designer Molecules, maleimide group equivalent 750 g/eq.) were added to the resin composition. Resin sheets were produced in the same manner as in Example 1 except for the above matters.

[Example 5] Instead of the active ester curing agent containing a dicyclopentadiene-type diphenol structure ("HPC-8000-65T" manufactured by DIC Corporation), 25 parts of an active ester compound containing a naphthalene structure ("HPC-8150-62T" manufactured by DIC Corporation, a toluene solution containing 62% of non-volatile components by mass, an active ester group equivalent of 229 g/eq.) were used. In addition, the amount of the curing accelerator (the imidazole compound "1B2PZ" manufactured by Shikoku Chemical Co., Ltd.) was changed from 0.5 parts to 0.1 parts. Furthermore, 5 parts of a cresol novolac curing agent containing a tris-bonded skeleton ("LA-3018-50P" manufactured by DIC Corporation, a hydroxyl equivalent: about 151, a 2-methoxypropanol solution containing 50% of non-volatile components) were added to the resin composition. The resin sheet was produced in the same manner as in Example 1 except for the above matters.

[Comparative Example 1] Maleimide compound _A1 was not used. In addition, 30 parts of an active ester compound containing a naphthalene structure (DIC "HPC-8150-62T", a toluene solution containing 62% by mass of nonvolatile components, and an active ester group equivalent of 229 g/eq.) were used instead of an active ester curing agent containing a dicyclopentadiene-type diphenol structure (DIC "HPC-8000-65T"). Furthermore, the amount of the inorganic filler was changed from 80 parts to 55 parts. The resin sheet was produced in the same manner as in Example 1 except for the above matters.

[Comparative Example 2] 20 parts of a biphenylaralkyl maleimide compound ("MIR-3000-70MT" manufactured by Nippon Kayaku Co., Ltd., maleimide equivalent: ₂₇₅ g/eq., MEK/toluene mixed solution with 70% non-volatile content) were used instead of 20 parts of the maleimide compound A1 (solution with 70% non-volatile content by mass). Furthermore, 30 parts of an active ester compound containing a naphthalene structure ("HPC-8150-62T" manufactured by DIC Corporation, toluene solution with 62% non-volatile content by mass, active ester equivalent 229 g/eq.) were used instead of an active ester curing agent containing a dicyclopentadiene-type diphenol structure ("HPC-8000-65T" manufactured by DIC Corporation). A resin sheet was produced in the same manner as in Example 1 except for the above matters.

[Comparative Example 3] 14 parts of a liquid aliphatic maleimide compound ("BMI-1500" manufactured by Designer Molecules, maleimide group equivalent 750 g/eq.) were used instead of 20 parts of maleimide compound _A1 (solution containing 70% by mass of nonvolatile components). Also, 30 parts of an active ester compound containing a naphthalene structure ("HPC-8150-62T" manufactured by DIC, toluene solution containing 62% by mass of nonvolatile components, active ester group equivalent 229 g/eq.) were used instead of an active ester curing agent containing a dicyclopentadiene-type diphenol structure ("HPC-8000-65T" manufactured by DIC). A resin sheet was produced in the same manner as in Example 1 except for the above matters.

[Measurement of dielectric properties] The resin sheets prepared in the examples and comparative examples were heated at 200°C for 90 minutes to thermally cure the resin composition layer. Then, the support was peeled off to obtain a cured product of the resin composition. This cured product was cut into test pieces with a width of 2 mm and a length of 80 mm. For the test piece, the dielectric constant Dk and dielectric tangent Df were measured by the cavity resonance perturbation method at a measurement frequency of 5.8 GHz and a measurement temperature of 23°C using "HP8362B" manufactured by Agilent Technologies. The measurements were performed on 3 test pieces, and the average values are shown in the following table.

[Determination of plating peel strength] (1) Base treatment of inner circuit substrate: As the inner circuit substrate, a glass cloth-based epoxy resin copper-coated laminate (copper foil thickness 18μm, substrate thickness 0.4mm, "R1515A" manufactured by PANASONIC) with inner circuits (copper foil) on both sides was prepared. Both sides of the inner circuit substrate were etched 1μm with "CZ8101" manufactured by MEC to roughen the copper surface.

(2) Lamination of resin sheets: A batch vacuum pressure laminator (manufactured by NIKKO Materials Co., Ltd., 2-stage expansion laminator, CVP700) is used to laminate the resin sheets to both sides of the inner circuit substrate. The lamination is performed by bringing the resin composition layer of the resin sheet into contact with the inner circuit substrate. The lamination is performed by reducing the pressure for 30 seconds to reduce the air pressure to below 13hPa, and by pressing at 130°C and a pressure of 0.74MPa for 45 seconds. Then, hot pressing is performed at 120°C and a pressure of 0.5MPa for 75 seconds.

(3) Curing of the resin composition: The laminated resin sheet and inner circuit substrate are heated at 130°C for 30 minutes and then at 170°C for 30 minutes to cure the resin composition and form an insulating layer. Then, the support is peeled off to obtain a laminate substrate having an insulating layer, an inner circuit substrate and an insulating layer in sequence.

(4) Roughening treatment: The laminated substrate is immersed in a swelling liquid (Swelling Dip Securigant P (glycol ethers, aqueous solution of sodium hydroxide) containing diethylene glycol monobutyl ether manufactured by ATOTECH Japan) for 10 minutes at 60°C. Next, the laminated substrate is immersed in a roughening liquid (Concentrate Compact P (an aqueous solution of _KMnO4 : 60 g/L, NaOH: 40 g/L) manufactured by ATOTECH Japan) for 20 minutes at 80°C. Then, the laminated substrate is immersed in a neutralizing liquid (Reduction Solution Securigant P (an aqueous solution of sulfuric acid) manufactured by ATOTECH Japan) for 5 minutes at 40°C. Then, the laminated substrate is dried at 80°C for 30 minutes to obtain an "evaluation substrate A".

(5) Semi-additive plating: Evaluation substrate A was immersed in an electroless plating solution containing _PdCl2 at 40°C for 5 minutes, and then immersed in an electroless copper plating solution at 25°C for 20 minutes. Then, it was heated at 150°C for 30 minutes to perform an annealing treatment. Then, an etching resist was formed to form a pattern caused by etching. Then, copper sulfate electrolytic plating was performed to form a conductive layer with a thickness of 20μm. Then, an annealing treatment was performed at 200°C for 60 minutes to obtain "evaluation substrate B".

(6) Determination of coating peel strength: In the conductive layer of the evaluation substrate B, a rectangular portion with a width of 10 mm and a length of 100 mm was cut. One end of the rectangular portion was peeled off and grasped with a clamp (Autocom tester "AC-50C-SL" manufactured by TSE). At room temperature, the load (kgf/cm) when the rectangular portion of 35 mm was torn off in the vertical direction at a speed of 50 mm/min was measured. This was taken as the coating peel strength.

[Measurement of surface roughness Ra] The arithmetic average roughness Ra of the insulating layer of the evaluation substrate A prepared in the above-mentioned [Measurement of coating peel strength] was measured. The measurement was performed using a non-contact surface roughness meter (WYKO NT3300 manufactured by VEECO Instruments) in VSI mode and a 50x lens with the measurement range set to 121μm×92μm. This measurement was performed at 10 measurement points, and the average values are shown in the following table.

[Measurement of glass transition temperature Tg] The resin sheet was heated in an oven at 190°C for 90 minutes to harden the resin composition layer. Then, the support was peeled off to obtain a hardened material of the resin composition layer. From this hardened material, a length of 20 mm and a width of 6 mm were cut to obtain a hardened material for evaluation. For this hardened material for evaluation, a thermomechanical analyzer (TMA) manufactured by RIGAKU was used to obtain the first TMA curve from 25°C to 250°C at a heating rate of 5°C/min by the tensile weight method. Then, the same measurement was performed on the same hardened material for evaluation to obtain the second TMA curve. From the TMA curve obtained for the second time, the value of the glass transition temperature Tg (°C) was calculated.

[Results] The following Table 1 shows the results of the embodiment and the comparative example.

Claims (13)

A resin composition comprising (A) a maleimide compound, (B) an epoxy resin, (C) an active ester-based hardener, and (D) an inorganic filler, wherein the (A) maleimide compound comprises (A-1) a maleimide compound having a trimethylindane skeleton, the component (A-1) comprises a structure represented by the following formula (A4), the amount of the component (D) is 20% to 90% by mass relative to 100% by mass of a non-volatile component in the resin composition, the amount of the component (A-1) is 2% to 40% by mass relative to 100% by mass of the inorganic filler (D), In formula (A4), Ar ^a1 represents a divalent aromatic alkyl group which may have a substituent; R ^a1 each independently represents an alkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, an alkylthio group having 1 to 10 carbon atoms, an aryl group having 6 to 10 carbon atoms, an aryloxy group having 6 to 10 carbon atoms, an arylthio group having 6 to 10 carbon atoms, a cycloalkyl group having 3 to 10 carbon atoms, a halogen atom, a nitro group, a hydroxyl group or a hydroxyl group; R ^a2 each independently represents an alkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, an alkylthio group having 1 to 10 carbon atoms, an aryl group having 6 to 10 carbon atoms, an aryloxy group having 6 to 10 carbon atoms, an arylthio group having 6 to 10 carbon atoms, a cycloalkyl group having 3 to 10 carbon atoms, a halogen atom, a hydroxyl group or a hydroxyl group; R ^a3 each independently represents a divalent aliphatic alkyl group; n _a1 represents a positive integer; n _a2 each independently represents an integer from 0 to 4; n _a3 each independently represents an integer from 0 to 3; the hydrogen atom of the alkyl group, alkoxy group, alkylthio group, aryl group, aryloxy group, arylthio group and cycloalkyl group of R ^a1 may be substituted by a halogen atom; the hydrogen atom of the alkyl group, alkoxy group, alkylthio group, aryl group, aryloxy group, arylthio group and cycloalkyl group of R ^a2 may be substituted by a halogen atom; when n _a2 is 2 to 4, R ^a1 may be the same or different in the same ring; when n _a3 is 2 to 3, R ^a2 may be the same or different in the same ring. A resin composition comprising (A) a maleimide compound, (B) an epoxy resin, (C) an active ester-based hardener, and (D) an inorganic filler, wherein the (A) maleimide compound comprises (A-1) a maleimide compound having a trimethylindane skeleton, and the component (A-1) comprises a structure represented by the following formula (A4); the amount of the component (A-1) is 60% by mass to 200% by mass relative to 100% by mass of the epoxy resin (B) in the resin composition, the amount of the component (D) is 20% by mass to 90% by mass relative to 100% by mass of a non-volatile component in the resin composition, In formula (A4), Ar ^a1 represents a divalent aromatic alkyl group which may have a substituent; R ^a1 each independently represents an alkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, an alkylthio group having 1 to 10 carbon atoms, an aryl group having 6 to 10 carbon atoms, an aryloxy group having 6 to 10 carbon atoms, an arylthio group having 6 to 10 carbon atoms, a cycloalkyl group having 3 to 10 carbon atoms, a halogen atom, a nitro group, a hydroxyl group or a hydroxyl group; R ^a2 each independently represents an alkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, an alkylthio group having 1 to 10 carbon atoms, an aryl group having 6 to 10 carbon atoms, an aryloxy group having 6 to 10 carbon atoms, an arylthio group having 6 to 10 carbon atoms, a cycloalkyl group having 3 to 10 carbon atoms, a halogen atom, a hydroxyl group or a hydroxyl group; R ^a3 each independently represents a divalent aliphatic alkyl group; n _a1 represents a positive integer; n _a2 each independently represents an integer from 0 to 4; n _a3 each independently represents an integer from 0 to 3; the hydrogen atom of the alkyl group, alkoxy group, alkylthio group, aryl group, aryloxy group, arylthio group and cycloalkyl group of R ^a1 may be substituted by a halogen atom; the hydrogen atom of the alkyl group, alkoxy group, alkylthio group, aryl group, aryloxy group, arylthio group and cycloalkyl group of R ^a2 may be substituted by a halogen atom; when n _a2 is 2 to 4, R ^a1 may be the same or different in the same ring; when n _a3 is 2 to 3, R ^a2 may be the same or different in the same ring. The resin composition of claim 1, wherein the amount of the component (A-1) is 0.5 mass % to 70 mass % relative to 100 mass % of the resin component in the resin composition. The resin composition of claim 1, wherein the amount of component (A) is 0.5 mass % or more and 70 mass % or less relative to 100 mass % of the resin component in the resin composition. The resin composition of claim 2, wherein the amount of the component (A-1) is 0.5 mass % to 60 mass % relative to 100 mass % of the resin component in the resin composition. The resin composition of claim 2, wherein the amount of component (A) is not less than 0.5 mass % and not more than 60 mass % relative to 100 mass % of the resin component in the resin composition. The resin composition of claim 1 or 2, wherein the amount of component (B) is 3 mass % or more and 50 mass % or less relative to 100 mass % of the resin component in the resin composition. The resin composition of claim 1 or 2, wherein the amount of the component (C) is 6 mass % or more and 80 mass % or less relative to 100 mass % of the resin component in the resin composition. The resin composition of claim 1 or 2 is used to form an insulating layer. A cured product of the resin composition according to any one of claims 1 to 9. A resin sheet comprises a support and a resin composition layer formed on the support using the resin composition of any one of claims 1 to 9. A printed wiring board comprising an insulating layer formed of a cured product of the resin composition according to any one of claims 1 to 9. A semiconductor device comprising a printed wiring board as claimed in claim 12.