JP7680839B2 - Resin materials and multilayer printed wiring boards - Google Patents

Description

The present invention relates to a resin material containing a compound having an imide skeleton. The present invention also relates to a multilayer printed wiring board using the resin material.

Conventionally, various resin materials have been used to obtain electronic components such as semiconductor devices, laminates, and printed wiring boards. For example, in multilayer printed wiring boards, resin materials are used to form insulating layers for insulating between internal layers and to form insulating layers located on the surface. Wiring, which is generally metal, is laminated on the surface of the insulating layer. In addition, resin films in which the resin materials are filmized may be used to form the insulating layers. The resin materials and resin films are used as insulating materials for multilayer printed wiring boards, including build-up films.

The following Patent Document 1 discloses a resin composition containing a compound having a maleimide group, a divalent group having at least two imide bonds, and a saturated or unsaturated divalent hydrocarbon group. Patent Document 1 describes that a cured product of this resin composition can be used as an insulating layer for a multilayer printed wiring board or the like.

The following Patent Document 2 discloses a resin composition comprising (A) an epoxy resin and (B) a maleimide compound, in which component (B) contains at least one of an alkyl group having 5 or more carbon atoms and an alkylene group having 5 or more carbon atoms.

The following Patent Document 3 discloses a resin composition for electronic materials that contains a bismaleimide compound having two maleimide groups and one or more polyimide groups having a specific structure. In the bismaleimide compound, the two maleimide groups are each independently bonded to both ends of the polyimide group via at least a first linking group in which eight or more atoms are linearly linked.

The following Patent Document 4 discloses a thermosetting resin composition used to form an insulating layer in a printed wiring board, the resin composition containing a maleimide compound (A) and containing at least a bismaleimide compound (A1) having a specific structure.

WO2016/114286A1 JP 2019-44128 A JP 2018-90728 A JP 2016-196549 A

When an insulating layer is formed using a conventional resin material such as that described in Patent Document 1, the thermal dimensional stability of the cured product may not be sufficiently high. Also, when an insulating layer is formed using a conventional resin material such as that described in Patent Document 2, the dielectric tangent of the cured product may not be sufficiently low. As described in Patent Documents 3 and 4, when a resin material containing a maleimide compound having a specific structure is used, the dielectric tangent and thermal dimensional stability can be improved to a certain extent, but further improvement is desired.

Furthermore, with conventional resin materials such as those described in Patent Documents 1-4, smears within the vias may not be sufficiently removed by the desmear process during the formation of the insulating layer.

Furthermore, when an insulating layer is formed using conventional resin materials, the surface roughness after etching may vary, and the plating peel strength with the metal layer laminated on the surface of the insulating layer by plating may not be sufficiently high.

The object of the present invention is to provide a resin material that can 1) reduce the dielectric tangent of the cured product, 2) increase the thermal dimensional stability of the cured product, 3) effectively remove smears by desmearing, 4) reduce the variation in surface roughness after etching, and 5) increase plating peel strength. Another object of the present invention is to provide a multilayer printed wiring board using the above resin material.

According to a broad aspect of the present invention, there is provided a resin material comprising a compound having a structure represented by the following formula (X) and a curing accelerator:

In the formula (X), R represents an organic group and n represents a number of 1 or more.

In a particular aspect of the resin material of the present invention, in formula (X), n represents a number of 2 or more.

In a particular aspect of the resin material according to the present invention, in formula (X), R is a group having an aliphatic ring.

In a particular aspect of the resin material according to the present invention, in formula (X), R has a partial skeleton derived from a dimer diamine.

In a particular aspect of the resin material according to the present invention, in formula (X), R has a partial skeleton derived from a diamine compound other than dimer diamine.

In a particular aspect of the resin material according to the present invention, in the compound, the nitrogen atoms constituting the imide skeleton are bonded only to the carbon atoms constituting the aliphatic skeleton.

In a particular aspect of the resin material of the present invention, the compound is a compound having a maleimide skeleton.

In a particular aspect of the resin material of the present invention, the compound is a compound having a maleimide skeleton at both ends.

In a particular aspect of the resin material of the present invention, the weight average molecular weight of the compound is 1,000 or more and 100,000 or less.

In a specific aspect of the resin material according to the present invention, the compound has a structure represented by the following formula (Y), and the number of repetitions of the structure represented by the formula (X) and the number of repetitions of the structure represented by the formula (Y) is 10% or more and 90% or less of the total 100% of the number of repetitions of the structure represented by the formula (X):

In the formula (Y), R1 represents a tetravalent organic group, R2 represents an organic group, and m represents a number of 1 or more.

In a particular aspect of the resin material of the present invention, in formula (Y), R1 does not have a skeleton derived from phthalimide, and in formula (Y), R2 does not have a skeleton derived from phthalimide.

In a particular aspect of the resin material of the present invention, in formula (Y), R1 does not have an aromatic skeleton.

In one particular aspect, the resin material of the present invention comprises a thermosetting compound and a curing agent, and the thermosetting compound comprises an epoxy compound.

In a particular aspect of the resin material of the present invention, the curing agent comprises an active ester compound.

In a particular aspect of the resin material of the present invention, at least one of the epoxy compound and the active ester compound has an imide skeleton or an amide skeleton.

In a particular aspect of the resin material of the present invention, the thermosetting compound includes a radically curable compound.

In a particular aspect of the resin material of the present invention, the resin material contains an inorganic filler.

In a particular aspect of the resin material of the present invention, the content of the inorganic filler is 50% by weight or more out of 100% by weight of the components excluding the solvent in the resin material.

In a particular aspect of the resin material of the present invention, the inorganic filler is silica.

In one particular aspect of the resin material of the present invention, the resin material is a resin film.

The resin material of the present invention is suitable for use in forming insulating layers in multilayer printed wiring boards.

According to a broad aspect of the present invention, there is provided a multilayer printed wiring board comprising a circuit board, a plurality of insulating layers disposed on a surface of the circuit board, and a metal layer disposed between the plurality of insulating layers, at least one of the plurality of insulating layers being a cured product of the resin material described above.

The resin material according to the present invention includes a compound having a structure represented by formula (X) and a curing accelerator. The resin material according to the present invention has the above-mentioned configuration, and therefore 1) the dielectric tangent of the cured product can be reduced, 2) the thermal dimensional stability of the cured product can be increased, 3) smears can be effectively removed by desmearing, 4) the variation in surface roughness after etching can be suppressed, and 5) plating peel strength can be increased.

FIG. 1 is a cross-sectional view showing a multilayer printed wiring board using a resin material according to one embodiment of the present invention.

The present invention is described in detail below.

The resin material according to the present invention contains a compound having a structure represented by the following formula (X) (hereinafter, sometimes referred to as compound X) and a curing accelerator.

In the above formula (X), R represents an organic group and n represents a number of 1 or more.

The resin material according to the present invention has the above-mentioned configuration, and therefore 1) the dielectric tangent of the cured product can be lowered, 2) the thermal dimensional stability of the cured product can be increased, 3) smears can be effectively removed by desmearing, 4) variations in surface roughness after etching can be suppressed, and 5) plating peel strength can be increased. The resin material according to the present invention can achieve all of the effects 1)-5).

In addition, since the resin material according to the present invention has the above-mentioned configuration, it is possible to improve the compatibility of the resin material. In addition, since the resin material according to the present invention has the above-mentioned configuration, it is possible to improve the elongation characteristics of the cured product of the resin material.

The resin material according to the present invention may be a resin composition or a resin film. The resin composition has fluidity. The resin composition may be in a paste form. The paste form includes a liquid form. Since the resin material according to the present invention has excellent handleability, it is preferable that the resin material is a resin film.

The resin material according to the present invention is preferably a thermosetting resin material. When the resin material is a resin film, the resin film is preferably a thermosetting resin film.

Below, we will explain the details of each component used in the resin material of the present invention, as well as uses of the resin material of the present invention.

[Compound X]
The resin material according to the present invention contains a compound X having a structure represented by the following formula (X). The structure represented by the following formula (X) has a skeleton derived from 3,3',4,4'-biphenyltetracarboxylic dianhydride. The structure represented by the following formula (X) has an imide skeleton. Therefore, the compound X has an imide skeleton. The compound X is preferably a thermosetting compound. Only one type of compound X may be used, or two or more types may be used in combination. Preferred structures and the like that can more effectively exert the effects of the present invention will be specifically described below.

In the above formula (X), R represents an organic group and n represents a number of 1 or more.

In the above formula (X), n preferably represents a number of 2 or more, preferably a number of 20 or less, and more preferably a number of 10 or less.

In the above formula (X), R may be a group having an aliphatic ring. Examples of the group having an aliphatic ring include a group having a cyclohexane ring and a group that forms part of a skeleton derived from dimer diamine.

In order to more effectively exert the effects of the present invention, in the above formula (X), R is preferably a group having an aliphatic ring, and more preferably a group having a cyclohexane ring.

In this specification, the cyclohexane ring means a six-membered alicyclic structure in which six carbon atoms are bonded in a ring. The carbon atoms constituting the cyclohexane ring may be bonded to a hydrocarbon group having 1 to 20 carbon atoms, or may be bonded to a hydrocarbon group having 1 to 4 carbon atoms. The compound X may have a cyclohexane ring as a ring constituting a tricyclodecane ring, a norbornane ring, an adamantane skeleton, or the like. The compound X may have a structure in which multiple cyclohexane rings are connected via a hydrocarbon group such as an alkyl group.

When R in the above formula (X) is a group having a cyclohexane ring, it is preferable that the carbon atom constituting the cyclohexane ring is directly bonded to a nitrogen atom in the skeleton derived from 3,3',4,4'-biphenyltetracarboxylic dianhydride or is bonded via three or less atoms. The atoms are preferably carbon atoms.

When R in the above formula (X) has the above tricyclodecane ring as the cyclohexane ring, it is preferable that the carbon atom constituting the tricyclodecane ring is directly bonded to the nitrogen atom in the skeleton derived from 3,3',4,4'-biphenyltetracarboxylic dianhydride or is bonded via two or less atoms. The atoms are preferably carbon atoms.

From the viewpoint of exerting the effects of the present invention even more effectively, in the above formula (X), it is preferable that R is a group represented by the following formula (A1), the following formula (A2), the following formula (A3), the following formula (A4), the following formula (A5), the following formula (A6), or the following formula (A7).

In the above formula (A1), R1 to R10 each represent a hydrogen atom or a hydrocarbon group having 1 to 20 carbon atoms. In the above formula (A1), it is preferable that R1 to R10 each represent a hydrogen atom or a methyl group. In the above formula (A1), R1 to R10 may be the same or different.

The group represented by the above formula (A1) has a cyclohexane ring.

In the structure represented by formula (X) having a group represented by formula (A1) above, the carbon atom constituting the cyclohexane ring and the nitrogen atom in the skeleton derived from 3,3',4,4'-biphenyltetracarboxylic dianhydride are bonded via one carbon atom.

In the above formula (A2), R1 to R10 each represent a hydrogen atom or a hydrocarbon group having 1 to 20 carbon atoms. In the above formula (A2), it is preferable that R1 to R10 each represent a hydrogen atom or a methyl group. In the above formula (A2), R1 to R10 may be the same or different.

The group represented by the above formula (A2) has a cyclohexane ring.

In the structure represented by formula (X) having a group represented by formula (A2), the first carbon atom (left carbon atom) constituting the cyclohexane ring is directly bonded to a nitrogen atom in the skeleton derived from 3,3',4,4'-biphenyltetracarboxylic dianhydride. In the structure represented by formula (X) having a group represented by formula (A2), the second carbon atom (right carbon atom) constituting the cyclohexane ring is bonded to a nitrogen atom in the skeleton derived from 3,3',4,4'-biphenyltetracarboxylic dianhydride via one carbon atom.

In the above formula (A3), R1 to R10 each represent a hydrogen atom or a hydrocarbon group having 1 to 20 carbon atoms. In the above formula (A3), it is preferable that R1 to R10 each represent a hydrogen atom or a methyl group. In the above formula (A3), R1 to R10 may be the same or different.

The group represented by the above formula (A3) has a cyclohexane ring.

In the structure represented by formula (X) having a group represented by formula (A3), the first carbon atom (left carbon atom) constituting the cyclohexane ring is bonded to a nitrogen atom in the skeleton derived from 3,3',4,4'-biphenyltetracarboxylic dianhydride via two carbon atoms. In the structure represented by formula (X) having a group represented by formula (A3), the second carbon atom (right carbon atom) constituting the cyclohexane ring is bonded directly to a nitrogen atom in the skeleton derived from 3,3',4,4'-biphenyltetracarboxylic dianhydride.

In the above formula (A4), R1 to R18 each represent a hydrogen atom or a hydrocarbon group having 1 to 20 carbon atoms, and Q represents any group. In the above formula (A4), it is preferable that R1 to R18 each represent a hydrogen atom or a methyl group. In the above formula (A4), it is preferable that Q represent a hydrocarbon group having 1 to 4 carbon atoms or a group having an aromatic ring, more preferably an alkylene group, and even more preferably a methylene group. In the above formula (A4), when Q represents a group having an aromatic ring, Q may be a group in which the aromatic rings are bonded to each other via an ester bond. In the above formula (A4), R1 to R18 may be the same or different.

The group represented by the above formula (A4) has a cyclohexane ring.

In the structure represented by formula (X) having a group represented by formula (A4), the first carbon atom (left carbon atom) constituting the cyclohexane ring is directly bonded to a nitrogen atom in the skeleton derived from 3,3',4,4'-biphenyltetracarboxylic dianhydride. In the structure represented by formula (X) having a group represented by formula (A4), the second carbon atom (right carbon atom) constituting the cyclohexane ring is directly bonded to a nitrogen atom in the skeleton derived from 3,3',4,4'-biphenyltetracarboxylic dianhydride.

In the above formula (A5), R1 to R8 each represent a hydrogen atom or a hydrocarbon group having 1 to 20 carbon atoms. In the above formula (A5), it is preferable that R1 to R8 each represent a hydrogen atom or a methyl group. In the above formula (A5), R1 to R8 may be the same or different.

In addition, in the above formula (X), R may be a group represented by the following formula (A5-1).

In the above formula (A5-1), R1 to R10 each represent a hydrogen atom or a hydrocarbon group having 1 to 20 carbon atoms, and two of R1 to R10 represent groups bonded to the nitrogen atom constituting the imide skeleton. In the above formula (A5-1), when R9 and R10 represent groups bonded to the nitrogen atom constituting the imide skeleton, this corresponds to the above formula (A5).

The groups represented by the above formula (A5) and formula (A5-1) have a norbornane ring.

In the structure represented by formula (X) having groups represented by formula (A5) and formula (A5-1), the carbon atom constituting the cyclohexane ring and the nitrogen atom in the skeleton derived from 3,3',4,4'-biphenyltetracarboxylic dianhydride are bonded via one carbon atom.

In the above formula (A6), R1 to R12 each represent a hydrogen atom or a hydrocarbon group having 1 to 20 carbon atoms. In the above formula (A6), it is preferable that R1 to R12 each represent a hydrogen atom or a methyl group. In the above formula (A6), R1 to R12 may be the same or different.

In addition, in the above formula (X), R may be a group represented by the following formula (A6-1).

In the above formula (A6-1), R1 to R14 each represent a hydrogen atom or a hydrocarbon group having 1 to 20 carbon atoms, and two of R1 to R14 represent a group bonded to the nitrogen atom constituting the imide skeleton. In the above formula (A6-1), when R13 and R14 represent a group bonded to the nitrogen atom constituting the imide skeleton, it corresponds to the above formula (A6).

The groups represented by the above formula (A6) and formula (A6-1) have a tricyclodecane ring.

In the structure represented by formula (X) having the groups represented by formula (A6) and formula (A6-1), the first carbon atom (left carbon atom) constituting the cyclohexane ring and the nitrogen atom in the skeleton derived from 3,3',4,4'-biphenyltetracarboxylic dianhydride are bonded via one carbon atom. In the structure represented by formula (X) having the groups represented by formula (A6) and formula (A6-1), the second carbon atom (right carbon atom) constituting the cyclohexane ring and the nitrogen atom in the skeleton derived from 3,3',4,4'-biphenyltetracarboxylic dianhydride are bonded via two carbon atoms. In the structure represented by formula (X) having the groups represented by formula (A6) and formula (A6-1), the second carbon atom (right carbon atom) constituting the tricyclodecane ring and the nitrogen atom in the skeleton derived from 3,3',4,4'-biphenyltetracarboxylic dianhydride are bonded via one carbon atom.

The group represented by the above formula (A7) has a cyclohexane ring. The group represented by the above formula (A7) is a group derived from dimer diamine. When synthesizing compound X having a group represented by the above formula (A7), dimer diamine is used as a raw material. However, since dimer diamine is a natural product (mixture), it is difficult to define the structure of the dimer diamine as a single structure. Therefore, in the obtained compound X, in addition to the group represented by the above formula (A7), for example, a compound having a group having a double bond in the above formula (A7) may be present.

From the viewpoint of exerting the effects of the present invention more effectively, it is preferable that in the compound X, in the above formula (X), R has a partial skeleton of a skeleton derived from a dimer diamine, and it is also preferable that R has a partial skeleton of a skeleton derived from a diamine compound other than dimer diamine.

From the viewpoint of exerting the effects of the present invention more effectively, in the above formula (X), it is preferable that the nitrogen atom constituting the imide skeleton is bonded only to the carbon atom constituting the aliphatic skeleton. From the viewpoint of exerting the effects of the present invention more effectively, in the above compound X, it is preferable that the nitrogen atom constituting the imide skeleton is bonded only to the carbon atom constituting the aliphatic skeleton.

From the viewpoint of exerting the effects of the present invention more effectively, it is preferable that the compound X has, as R in the formula (X), a group represented by the formula (A5), the formula (A6) or the formula (A7), and it is more preferable that the compound X has a group represented by the formula (A6) or the formula (A7).

From the viewpoint of further enhancing the desmear property and further enhancing the thermal dimensional stability, it is preferable that the compound X has a group represented by the above formula (A5) or the above formula (A6) as R in the above formula (X). This is because the compound X having the group represented by the above formula (A5) or the above formula (A6) has a shorter distance between imide skeletons than the compound X having the group represented by the above formula (A7), and therefore it is possible to increase the concentration of imide skeletons in the molecule.

The compound X may have two, two or more, or three or more of the structures represented by the formula (X).

For example, the compound X may have a structure represented by the following formula (X1) as the structure represented by the above formula (X). The two skeletons (skeleton A on the left side and skeleton B on the right side) of the structure represented by the following formula (X1) may be randomly arranged (for example, ...A/B/A/B..., etc.).

In the above formula (X1), R1 and R2 each represent an organic group, and p and q each represent a number of 1 or more.

In the above formula (X1), p and q each preferably represent a number of 2 or more, preferably a number of 10 or less, and more preferably a number of 7 or less.

In the above formula (X1), the combination of R1 and R2 is preferably the first combination below, and more preferably the second combination below.

First combination: R1 is the above formula (A1), the above formula (A2), the above formula (A3), the above formula (A4), the above formula (A5), or the above formula (A6), and R2 is the above formula (A7).

Second combination: R1 is the above formula (A6) and R2 is the above formula (A7).

When the above formula (X1) is the first combination, in the above formula (X1), p preferably represents a number of 1 or more, more preferably represents a number of 3 or more, preferably represents a number of 18 or less, and more preferably represents a number of 12 or less. When the above formula (X1) is the first combination, in the above formula (X1), q more preferably represents a number of 1 or more, preferably represents a number of 10 or less, and more preferably represents a number of 8 or less.

When the above formula (X1) is the second combination, in the above formula (X1), p preferably represents a number of 2 or more, more preferably represents a number of 3 or more, preferably represents a number of 18 or less, and more preferably represents a number of 12 or less. When the above formula (X1) is the second combination, in the above formula (X1), q preferably represents a number of 1 or more, more preferably represents a number of 2 or more, preferably represents a number of 10 or less, and more preferably represents a number of 8 or less.

Hereinafter, the compounds capable of forming the skeleton represented by the above formula (X) having groups represented by the above formulas (A1), (A2), (A3), (A4), (A5), (A6), and (A7) will be further described. Furthermore, the compounds capable of forming the skeleton represented by the above formula (X) having groups different from the groups represented by the above formulas (A1), (A2), (A3), (A4), (A5), (A6), and (A7) will be further described.

The structure represented by the above formula (X) can be obtained, for example, by reacting a diamine compound with 3,3',4,4'-biphenyltetracarboxylic dianhydride.

The above diamine compound may be an aliphatic diamine compound or may be a diamine compound different from an aliphatic diamine compound.

Examples of aliphatic diamine compounds include dimer diamine, tricyclodecane diamine, 1,3-bis(aminomethyl)cyclohexane, 1,4-bis(aminomethyl)cyclohexane, bis(aminomethyl)norbornane, 3(4),8(9)-bis(aminomethyl)tricyclo[5.2.1.02,6]decane, 1,3-cyclohexanediamine, 1,4-cyclohexanediamine, isophoronediamine, 4,4'-methylenebis(cyclohexylamine), and 4,4'-methylenebis(2-methylcyclohexylamine). Only one type of aliphatic diamine compound may be used, or two or more types may be used in combination.

Examples of the dimer diamine include VERSAMINE 551 (product name, manufactured by BASF Japan, 3,4-bis(1-aminoheptyl)-6-hexyl-5-(1-octenyl)cyclohexene), VERSAMINE 552 (product name, manufactured by Cognix Japan, hydrogenated VERSAMINE 551), and PRIAMINE 1075 and PRIAMINE 1074 (product names, both manufactured by Croda Japan).

From the viewpoint of further lowering the dielectric tangent of the cured product, it is preferable that the above dimer diamine is "PRIAMINE 1075" dimer diamine manufactured by Croda Japan.

From the viewpoint of further improving the desmearing property, it is preferable that the above dimer diamine is "PRIAMINE 1074" dimer diamine manufactured by Croda Japan.

In order to more effectively exert the effects of the present invention, it is preferable that the above-mentioned aliphatic diamine compound is a compound having 36 or less carbon atoms.

From the viewpoint of exerting the effects of the present invention more effectively, the aliphatic diamine compound is preferably dimer diamine, tricyclodecane diamine, bis(aminomethyl)norbornane, isophorone diamine, or 4,4'-methylene bis(2-methylcyclohexylamine). From the viewpoint of exerting the effects of the present invention more effectively, the aliphatic diamine compound is more preferably dimer diamine, tricyclodecane diamine, or bis(aminomethyl)norbornane. When the aliphatic diamine compound is bis(aminomethyl)norbornane, the compound X has, for example, a group represented by the above formula (A5). When the aliphatic diamine compound is tricyclodecane diamine, the compound X has, for example, a group represented by the above formula (A6). When the aliphatic diamine compound is dimer diamine, the compound X has, for example, a group represented by the above formula (A7).

Examples of diamine compounds different from the above aliphatic diamine compounds include 1,1-bis(4-aminophenyl)cyclohexane, 2,7-diaminofluorene, 4,4'-ethylenedianiline, 4,4'-methylenebis(2,6-diethylaniline), 4,4'-methylenebis(2-ethyl-6-methylaniline), 1,4-diaminobutane, 1,10-diaminodecane, 1,12-diaminododecane, 1,7-diaminoheptane, 1,6-diaminohexane, 1,5-diaminopentane, 1,8-diaminooctane, 1,3-diaminopropane, 1,11-diaminoundecane, 2-methyl-1,5-diaminopentane, 2,2-bis(3-amino-4-hydroxyphenyl)propane, and 2,2-bis(3-amino-4-hydroxyphenyl)hexafluoropropane. The diamine compound different from the aliphatic diamine compound may be used alone or in combination of two or more kinds.

The diamine compound other than the aliphatic diamine compound may be an aromatic diamine having a phenolic hydroxyl group. In this case, the linear expansion coefficient can be further reduced.

The compound X may have a skeleton derived from a reaction product of a diamine compound and an acid dianhydride other than 3,3',4,4'-biphenyltetracarboxylic dianhydride.

Examples of acid dianhydrides other than the above-mentioned 3,3',4,4'-biphenyltetracarboxylic dianhydride include tetracarboxylic dianhydrides, etc. Examples of the tetracarboxylic dianhydride include pyromellitic dianhydride, 3,3',4,4'-benzophenone tetracarboxylic dianhydride, 3,3',4,4'-biphenylsulfone tetracarboxylic dianhydride, 1,4,5,8-naphthalene tetracarboxylic dianhydride, 2,3,6,7-naphthalene tetracarboxylic dianhydride, 3,3',4,4'-biphenyl ether tetracarboxylic dianhydride, 3,3',4,4'-dimethyldiphenylsilane tetracarboxylic dianhydride, 3,3',4,4'-tetraphenylsilane tetracarboxylic dianhydride, 1,2,3,4-furan tetracarboxylic dianhydride, 4,4'-bis(3,4-dicarboxyphenoxy)diphenyl sulfide dianhydride, 4,4'-bis(3,4-dicarboxyphenoxy)diphenyl sulfone dianhydride, 4, 4'-bis(3,4-dicarboxyphenoxy)diphenylpropane dianhydride, 3,3',4,4'-perfluoroisopropylidenediphthalic dianhydride, bis(phthalic acid)phenylphosphine oxide dianhydride, p-phenylene-bis(triphenylphthalic acid) dianhydride, m-phenylene-bis(triphenylphthalic acid) dianhydride, bis(triphenylphthalic acid)-4,4'-diphenyl ether dianhydride, bis(triphenylphthalic acid)-4,4'-diphenylmethane dianhydride, 4,4'-(hexafluoroisopropylidene)diphthalic anhydride, bicyclo[2.2.2]oct-7-ene-2,3,5,6-tetracarboxylic acid dianhydride, and 5-(2,5-dioxotetrahydrofuryl)-3-methyl-3-cyclohexene-1,2-dicarboxylic acid anhydride.

From the viewpoint of lowering the dielectric tangent of the cured product and increasing the thermal dimensional stability of the cured product, it is preferable that the above compound X has a maleimide skeleton.

The number of maleimide skeletons in the compound X is preferably 2 or more, more preferably 3 or more, and preferably 10 or less, more preferably 5 or less. When the number of maleimide skeletons is equal to or more than the above lower limit and equal to or less than the above upper limit, the effects of the present invention can be more effectively exhibited.

From the viewpoint of further lowering the dielectric tangent of the cured product and further increasing the thermal dimensional stability of the cured product, it is preferable that the above compound X has a maleimide skeleton at both ends.

The compound X may or may not have a branched structure.

In order to more effectively exert the effects of the present invention, it is preferable that the compound X has a structure represented by the following formula (Y).

In the above formula (Y), R1 represents a tetravalent organic group, R2 represents an organic group, and m represents a number of 1 or more.

In the above formula (Y), m preferably represents a number of 2 or more, preferably a number of 20 or less, and more preferably a number of 10 or less.

In the above formula (Y), R1 may be a skeleton that does not have a biphenyl skeleton, such as a skeleton derived from an acid dianhydride other than the above-mentioned 3,3',4,4'-biphenyltetracarboxylic dianhydride. In the above formula (Y), R2 may be an organic group similar to the organic group of R in the above formula (X).

From the viewpoint of exerting the effects of the present invention more effectively, it is preferable that R1 in the above formula (Y) does not have a skeleton derived from phthalimide. From the viewpoint of exerting the effects of the present invention more effectively, it is preferable that R1 in the above formula (Y) does not have an aromatic skeleton.

In order to more effectively exert the effects of the present invention, it is preferable that R2 in the above formula (Y) does not have a skeleton derived from phthalimide.

In the compound X, the number of repeats (n) of the structure represented by the formula (X) and the number of repeats (m) of the structure represented by the formula (Y) are 100% in total, and the number of repeats (n) of the structure represented by the formula (X) is preferably 10% or more, more preferably 20% or more, preferably 90% or less, more preferably 75% or less, and even more preferably 60% or less. In this case, the effect of the present invention can be exerted even more effectively.

The compound X may have an even number of imide skeletons, an odd number of imide skeletons, or a mixture of a compound having an even number of imide skeletons and a compound having an odd number of imide skeletons.

The compound X can be synthesized, for example, as follows. A diamine compound, dimer diamine, and 3,3',4,4'-biphenyltetracarboxylic dianhydride are reacted to obtain a first reactant. The obtained first reactant is reacted with maleic anhydride.

Compound X having a dimer diamine skeleton at its terminal can be synthesized, for example, as follows. A diamine compound is reacted with 3,3',4,4'-biphenyltetracarboxylic dianhydride to obtain a first reactant having an acid anhydride structure at both terminals. The obtained first compound is reacted with dimer diamine to obtain a second reactant. The obtained second reactant is reacted with maleic anhydride.

The weight average molecular weight of the compound X is preferably 1000 or more, more preferably 3100 or more, even more preferably 4500 or more, preferably 100000 or less, more preferably 70000 or less, even more preferably 25000 or less, particularly preferably 18000 or less, and most preferably 15000 or less. When the weight average molecular weight is equal to or greater than the lower limit, the linear expansion coefficient can be further reduced. In addition, when the weight average molecular weight exceeds 25000, the melt viscosity of the resin material becomes higher than when the weight average molecular weight is 25000 or less, and the embeddability in the uneven surface may decrease.

The weight average molecular weight of the above compound X indicates the weight average molecular weight in terms of polystyrene measured by gel permeation chromatography (GPC).

From the viewpoint of further enhancing the thermal dimensional stability of the cured product and further enhancing the adhesion between the insulating layer and the metal layer, the glass transition temperature of the above compound X is preferably 70°C or higher, more preferably 85°C or higher.

The above glass transition temperature can be determined from the inflection point of the reverse heat flow by heating in a nitrogen atmosphere from -30°C to 260°C at a heating rate of 3°C/min using a differential scanning calorimeter (e.g., "Q2000" manufactured by TA Instruments).

In 100% by weight of the components excluding the inorganic filler and the solvent in the resin material, the content of the compound X is preferably 3% by weight or more, more preferably 5% by weight or more, even more preferably 10% by weight or more, preferably 80% by weight or less, more preferably 70% by weight or less, and even more preferably 50% by weight or less. When the content of the compound X is equal to or more than the lower limit, the dielectric tangent of the cured product can be further lowered and the desmearing property can be further improved. When the content of the compound X is equal to or less than the upper limit, the surface roughness of the resin material after the desmearing treatment can be reduced, and the embedding property of the unevenness of the substrate, etc. can be improved.

[Thermosetting compound]
The resin material preferably contains a thermosetting compound that does not have a structure represented by the following formula (100). The thermosetting compound is a thermosetting compound different from the compound X. The thermosetting compound may be used alone or in combination of two or more kinds.

In the above formula (100), R represents an organic group and n represents a number of 1 or more.

Examples of the thermosetting compounds include phenoxy compounds, oxetane compounds, maleimide compounds, epoxy compounds, cyanate compounds, vinyl compounds, polyarylate compounds, diallyl phthalate compounds, episulfide compounds, (meth)acrylic compounds, amino compounds, unsaturated polyester compounds, polyurethane compounds, and silicone compounds.

The thermosetting compound is preferably a maleimide compound, an epoxy compound, or a vinyl compound, more preferably contains an epoxy compound or a vinyl compound, and even more preferably contains an epoxy compound. The vinyl compound preferably contains a styrene compound or an acrylate compound, and more preferably contains a styrene compound. In this case, the dielectric tangent of the cured product can be further lowered and the thermal dimensional stability of the cured product can be further increased.

<Maleimide Compound>
The maleimide compound is a maleimide compound that does not have a structure represented by the formula (100). The maleimide compound is a maleimide compound different from the compound X. The maleimide compound may be a citraconimide compound. The maleimide compound may be used alone or in combination of two or more.

The maleimide compound may be a bismaleimide compound.

Examples of the maleimide compounds include N-phenylmaleimide and N-alkylbismaleimide.

The maleimide compound may or may not have a skeleton derived from a diamine compound other than a dimer diamine or a triamine compound other than a trimer triamine.

It is preferable that the maleimide compound has an aromatic skeleton.

In the above maleimide compound, it is preferable that the nitrogen atom in the maleimide skeleton is bonded to an aromatic ring.

From the viewpoint of further enhancing the thermal dimensional stability of the cured product, the content of the above maleimide compound is preferably 0.5% by weight or more, more preferably 1% by weight or more, preferably 15% by weight or less, more preferably 10% by weight or less, based on 100% by weight of the components excluding the solvent in the resin material.

The content of the maleimide compound in 100% by weight of the components excluding the inorganic filler and the solvent in the resin material is preferably 2.5% by weight or more, more preferably 5% by weight or more, preferably 50% by weight or less, more preferably 35% by weight or less, and even more preferably 20% by weight or less. When the content of the maleimide compound is equal to or more than the lower limit and equal to or less than the upper limit, the thermal dimensional stability of the cured product can be further improved.

In order to effectively exert the effects of the present invention, the molecular weight of the above maleimide compound is preferably 500 or more, more preferably 1,000 or more, and preferably less than 30,000, more preferably less than 20,000.

The molecular weight of the maleimide compound means the molecular weight that can be calculated from the structural formula when the maleimide compound is not a polymer and when the structural formula of the maleimide compound can be specified. When the maleimide compound is a polymer, the molecular weight of the maleimide compound means the weight average molecular weight in terms of polystyrene measured by gel permeation chromatography (GPC).

Commercially available examples of the maleimide compound include "BMI4000" and "BMI5100" manufactured by Daiwa Kasei Kogyo Co., Ltd., "MIR-3000" manufactured by Nippon Kayaku Co., Ltd., and "BMI-3000" and "BMI-689" manufactured by Designer Molecules Inc.

<Epoxy Compound>
As the epoxy compound, a conventionally known epoxy compound can be used. The epoxy compound is an organic compound having at least one epoxy group. The epoxy compound may be used alone or in combination of two or more kinds.

Examples of the epoxy compounds include bisphenol A type epoxy compounds, bisphenol F type epoxy compounds, bisphenol S type epoxy compounds, phenol novolac type epoxy compounds, biphenyl type epoxy compounds, biphenyl novolac type epoxy compounds, biphenol type epoxy compounds, naphthalene type epoxy compounds, fluorene type epoxy compounds, phenol aralkyl type epoxy compounds, naphthol aralkyl type epoxy compounds, dicyclopentadiene type epoxy compounds, anthracene type epoxy compounds, epoxy compounds having an adamantane skeleton, epoxy compounds having a tricyclodecane skeleton, naphthylene ether type epoxy compounds, and epoxy compounds having a triazine nucleus in the skeleton.

The epoxy compound may be a glycidyl ether compound. The glycidyl ether compound is a compound having at least one glycidyl ether group.

The epoxy compound may be an epoxy compound having a fluorine atom.

From the viewpoint of further lowering the dielectric tangent of the cured product and improving the thermal dimensional stability and flame retardancy, it is preferable that the above epoxy compound contains an epoxy compound having an aromatic skeleton, preferably an epoxy compound having a naphthalene skeleton or a phenyl skeleton, and more preferably an epoxy compound having an aromatic skeleton.

From the viewpoint of further lowering the dielectric tangent and improving the coefficient of linear expansion (CTE) of the cured product, it is preferable that the above epoxy compound contains an epoxy compound that is liquid at 25°C and an epoxy compound that is solid at 25°C.

The viscosity of the above-mentioned epoxy compound that is liquid at 25°C is preferably 1000 mPa·s or less, and more preferably 500 mPa·s or less, at 25°C.

The viscosity of the above epoxy compound can be measured, for example, using a dynamic viscoelasticity measuring device (VAR-100 manufactured by Rheologica Instruments).

It is more preferable that the molecular weight of the epoxy compound is 1000 or less. In this case, even if the content of the inorganic filler is 50% by weight or more out of 100% by weight of the components excluding the solvent in the resin material, a resin material with high fluidity can be obtained when forming the insulating layer. Therefore, when the uncured or B-staged resin material is laminated on the circuit board, the inorganic filler can be uniformly present.

The molecular weight of the epoxy compound means the molecular weight that can be calculated from the structural formula when the epoxy compound is not a polymer and when the structural formula of the epoxy compound can be specified. When the epoxy compound is a polymer, the molecular weight means the weight average molecular weight.

From the viewpoint of further enhancing the thermal dimensional stability of the cured product, the content of the above epoxy compound is preferably 4% by weight or more, more preferably 7% by weight or more, preferably 15% by weight or less, more preferably 12% by weight or less, based on 100% by weight of the components excluding the solvent in the resin material.

The content of the epoxy compound is preferably 15% by weight or more, more preferably 25% by weight or more, preferably 50% by weight or less, more preferably 40% by weight or less, based on 100% by weight of the components in the resin material excluding the inorganic filler and the solvent. When the content of the epoxy compound is equal to or more than the lower limit and equal to or less than the upper limit, the thermal dimensional stability of the cured product can be further improved.

The weight ratio of the content of the epoxy compound to the total content of the compound X and the curing agent described later (the content of the epoxy compound/the total content of the compound X and the curing agent described later) is preferably 0.2 or more, more preferably 0.3 or more. The weight ratio of the content of the epoxy compound to the total content of the compound X and the curing agent described later (the content of the epoxy compound/the total content of the compound X and the curing agent described later) is preferably 1 or less, more preferably 0.8 or less. When the weight ratio is equal to or more than the lower limit and equal to or less than the upper limit, the dielectric tangent can be further lowered and the thermal dimensional stability can be further improved.

<Vinyl Compounds>
As the vinyl compound, a conventionally known vinyl compound can be used. The vinyl compound is an organic compound having at least one vinyl group. The vinyl compound may be used alone or in combination of two or more kinds.

Examples of the vinyl compound include a styrene compound, an acrylate compound, and a divinyl compound. Examples of the divinyl compound include a divinyl benzyl ether compound. The vinyl compound may be a divinyl compound having an aliphatic skeleton or a divinyl ether compound.

The styrene compound may be a styrene-terminated phenylene ether compound. Only one type of the styrene compound may be used, or two or more types may be used in combination.

Commercially available styrene compounds include, for example, "OPE-2St" manufactured by Mitsubishi Gas Chemical Company, Inc.

In addition, the above-mentioned styrene compound and the above-mentioned vinyl compound such as the acrylate compound also correspond to a radical curing compound. Therefore, it is preferable that the above-mentioned thermosetting compound contains a radical curing compound. It is preferable that the above-mentioned resin material contains a radical curing compound.

The content of the vinyl compound is preferably 5% by weight or more, more preferably 10% by weight or more, even more preferably 20% by weight or more, preferably 80% by weight or less, more preferably 70% by weight or less, based on 100% by weight of the components in the resin material excluding the inorganic filler and the solvent. If the content of the vinyl compound is equal to or more than the lower limit and equal to or less than the upper limit, the thermal dimensional stability of the cured product can be further improved.

[Inorganic filler]
The resin material preferably contains an inorganic filler. By using the inorganic filler, the dielectric tangent of the cured product can be further reduced. In addition, by using the inorganic filler, the dimensional change of the cured product due to heat can be further reduced. The inorganic filler may be used alone or in combination of two or more kinds.

Examples of the inorganic fillers include silica, talc, clay, mica, hydrotalcite, alumina, magnesium oxide, aluminum hydroxide, diamond, aluminum nitride, and boron nitride.

The inorganic filler is preferably an inorganic filler having a thermal conductivity of 10 W/mK or more, such as alumina or boron nitride. In this case, heat dissipation can be improved.

From the viewpoint of reducing the surface roughness of the cured product, further increasing the adhesive strength between the cured product and the metal layer, forming finer wiring on the surface of the cured product, and imparting better insulation reliability to the cured product, the inorganic filler is preferably silica or alumina, more preferably silica, and even more preferably fused silica. The silica may be hollow silica. By using silica, the thermal expansion coefficient of the cured product is further reduced, and the dielectric tangent of the cured product is further reduced. In addition, by using silica, the surface roughness of the cured product is effectively reduced, and the adhesive strength between the cured product and the metal layer is effectively increased. The silica is preferably spherical in shape.

From the viewpoint of promoting the curing of the resin regardless of the curing environment, effectively increasing the glass transition temperature of the cured product, and effectively reducing the coefficient of linear thermal expansion of the cured product, it is preferable that the above-mentioned inorganic filler is spherical silica.

From the viewpoint of increasing thermal conductivity and insulating properties, it is preferable that the inorganic filler is alumina or boron nitride. In particular, boron nitride has anisotropy, which can further reduce the coefficient of linear thermal expansion.

The average particle size of the inorganic filler is preferably 50 nm or more, more preferably 100 nm or more, even more preferably 500 nm or more, and preferably 5 μm or less, more preferably 3 μm or less, and even more preferably 1 μm or less. When the average particle size of the inorganic filler is equal to or greater than the lower limit and equal to or less than the upper limit, the surface roughness after etching can be reduced and the plating peel strength can be increased, and the adhesion between the insulating layer and the metal layer can be further improved.

The median diameter (d50) at 50% is used as the average particle diameter of the inorganic filler. The average particle diameter can be measured using a particle size distribution measuring device that uses a laser diffraction scattering method. In addition, when the inorganic filler is an agglomerated particle, the average particle diameter of the inorganic filler means the primary particle diameter.

The inorganic filler is preferably spherical, and more preferably spherical silica. In this case, the surface roughness of the cured product is effectively reduced, and the adhesive strength between the cured product and the metal layer is effectively increased. When the inorganic filler is spherical, the aspect ratio of the inorganic filler is preferably 2 or less, and more preferably 1.5 or less.

The inorganic filler is preferably surface-treated, more preferably surface-treated with a coupling agent, and even more preferably surface-treated with a silane coupling agent. By surface-treating the inorganic filler, the surface roughness of the roughened cured product is further reduced, and the adhesive strength between the cured product and the metal layer is further increased. In addition, by surface-treating the inorganic filler, finer wiring can be formed on the surface of the cured product, and better inter-wiring insulation reliability and inter-layer insulation reliability can be imparted to the cured product.

Examples of the coupling agent include silane coupling agents, titanium coupling agents, and aluminum coupling agents. Examples of the silane coupling agent include methacrylsilane, acrylic silane, aminosilane, imidazole silane, vinyl silane, and epoxy silane.

The content of the inorganic filler in 100% by weight of the resin material excluding the solvent is preferably 50% by weight or more, more preferably 60% by weight or more, even more preferably 65% by weight or more, particularly preferably 68% by weight or more, preferably 90% by weight or less, more preferably 85% by weight or less, even more preferably 80% by weight or less, particularly preferably 75% by weight or less. When the content of the inorganic filler is equal to or greater than the lower limit, the dielectric tangent is effectively lowered. When the content of the inorganic filler is equal to or less than the upper limit, the thermal dimensional stability is improved and the warping of the cured product can be effectively suppressed. When the content of the inorganic filler is equal to or greater than the lower limit and equal to or less than the upper limit, the surface roughness of the cured product can be further reduced, and finer wiring can be formed on the surface of the cured product. Furthermore, with this content of the inorganic filler, it is possible to lower the thermal expansion coefficient of the cured product and at the same time improve the smear removability.

[Curing agent]
The resin material preferably contains a curing agent. The curing agent is not particularly limited. A conventionally known curing agent can be used as the curing agent. The curing agent may be used alone or in combination of two or more kinds.

Examples of the curing agent include phenol compounds (phenol curing agents), active ester compounds, cyanate ester compounds (cyanate ester curing agents), benzoxazine compounds without imide bonds (benzoxazine curing agents), carbodiimide compounds (carbodiimide curing agents), amine compounds (amine curing agents), thiol compounds (thiol curing agents), phosphine compounds, dicyandiamide, and acid anhydrides. It is preferable that the curing agent has a functional group capable of reacting with the epoxy group of the epoxy compound.

From the viewpoint of further increasing the thermal dimensional stability and further decreasing the dielectric tangent, it is preferable that the curing agent contains at least one component selected from the group consisting of a phenolic compound, an active ester compound, a cyanate ester compound, a benzoxazine compound having no imide bond, a carbodiimide compound, and an acid anhydride. From the viewpoint of further increasing the thermal dimensional stability and further decreasing the dielectric tangent, it is more preferable that the curing agent contains at least one component selected from the group consisting of a phenolic compound, an active ester compound, a cyanate ester compound, a benzoxazine compound having no imide bond, and a carbodiimide compound, and it is even more preferable that the curing agent contains an active ester compound.

From the viewpoint of further increasing the thermal dimensional stability and further decreasing the dielectric tangent, it is preferable that the thermosetting compound contains an epoxy compound and the curing agent contains both a phenol compound and an active ester compound.

Examples of the phenol compounds include novolac-type phenols, biphenol-type phenols, naphthalene-type phenols, dicyclopentadiene-type phenols, aralkyl-type phenols, and dicyclopentadiene-type phenols.

Commercially available phenol compounds include novolac phenol (DIC Corporation's "TD-2091"), biphenyl novolac phenol (Meiwa Chemical Industry Co., Ltd.'s "MEH-7851"), aralkyl phenol compounds (Meiwa Chemical Industry Co., Ltd.'s "MEH-7800"), and phenols having an aminotriazine skeleton (DIC Corporation's "LA-1356" and "LA-3018-50P").

The above-mentioned active ester compound refers to a compound that contains at least one ester bond in the structure and has an aliphatic chain, an aliphatic ring, or an aromatic ring bonded to both sides of the ester bond. The active ester compound is obtained, for example, by a condensation reaction between a carboxylic acid compound or a thiocarboxylic acid compound and a hydroxy compound or a thiol compound. An example of an active ester compound is a compound represented by the following formula (1).

In the above formula (1), X1 represents a group containing an aliphatic chain, a group containing an aliphatic ring, or a group containing an aromatic ring, and X2 represents a group containing an aromatic ring. Preferred examples of the group containing an aromatic ring include a benzene ring which may have a substituent, and a naphthalene ring which may have a substituent. Examples of the substituent include a hydrocarbon group. The number of carbon atoms in the hydrocarbon group is preferably 12 or less, more preferably 6 or less, and even more preferably 4 or less.

In the above formula (1), examples of the combination of X1 and X2 include a combination of a benzene ring which may have a substituent and a benzene ring which may have a substituent, and a combination of a benzene ring which may have a substituent and a naphthalene ring which may have a substituent. Furthermore, in the above formula (1), examples of the combination of X1 and X2 include a combination of a naphthalene ring which may have a substituent and a naphthalene ring which may have a substituent.

The active ester compound is not particularly limited. From the viewpoint of further improving the thermal dimensional stability and flame retardancy, it is preferable that the active ester compound is an active ester compound having two or more aromatic skeletons. From the viewpoint of lowering the dielectric tangent of the cured product and improving the thermal dimensional stability of the cured product, it is more preferable that the active ester compound has a naphthalene ring or a dicyclopentadiene skeleton in the main chain skeleton.

When the resin material contains the epoxy compound and the active ester compound, it is preferable that at least one of the epoxy compound and the active ester compound has an imide skeleton or an amide skeleton. In this case, the effect of the present invention can be exerted more effectively.

Commercially available products of the above active ester compounds include "HPC-8000-65T", "EXB9416-70BK", "EXB8100-65T", "HPC-8150-62T" and "EXB-8" manufactured by DIC Corporation.

From the viewpoint of lowering the melt viscosity of the resin material, shortening the distance between crosslinking points, and further reducing the linear expansion coefficient of the cured product, it is preferable that the active ester compound is an ester compound with low molecular weight activity. Commercially available ester compounds with low molecular weight activity include the above-mentioned "EXB-8" manufactured by DIC Corporation.

Examples of the cyanate ester compounds include novolac-type cyanate ester resins, bisphenol-type cyanate ester resins, and prepolymers in which these are partially trimerized. Examples of the novolac-type cyanate ester resins include phenol novolac-type cyanate ester resins and alkylphenol-type cyanate ester resins. Examples of the bisphenol-type cyanate ester resins include bisphenol A-type cyanate ester resins, bisphenol E-type cyanate ester resins, and tetramethylbisphenol F-type cyanate ester resins.

Commercially available products of the above cyanate ester compounds include phenol novolac type cyanate ester resins (PT-30 and PT-60 manufactured by Lonza Japan) and prepolymers of trimerized bisphenol type cyanate ester resins (BA-230S, BA-3000S, BTP-1000S, and BTP-6020S manufactured by Lonza Japan).

The content of the cyanate ester compound in 100% by weight of the components excluding the inorganic filler and the solvent in the resin material is preferably 10% by weight or more, more preferably 15% by weight or more, even more preferably 20% by weight or more, preferably 85% by weight or less, more preferably 75% by weight or less. When the content of the cyanate ester compound is equal to or more than the lower limit and equal to or less than the upper limit, the thermal dimensional stability of the cured product can be further improved.

Examples of benzoxazine compounds that do not have the above-mentioned imide bond include P-d type benzoxazine and Fa type benzoxazine.

Commercially available examples of benzoxazine compounds that do not have the above imide bonds include "P-d type" manufactured by Shikoku Chemical Industry Co., Ltd. and "ODA-BOZ" manufactured by JFE Chemical Corporation.

In 100% by weight of the components in the resin material excluding the inorganic filler and the solvent, the content of the benzoxazine compound not having the imide bond is preferably 1% by weight or more, more preferably 5% by weight or more, even more preferably 10% by weight or more, preferably 70% by weight or less, more preferably 60% by weight or less. When the content of the benzoxazine compound not having the imide bond is equal to or more than the lower limit and equal to or less than the upper limit, the dielectric tangent of the cured product can be lowered and the thermal dimensional stability can be further improved.

The carbodiimide compound is a compound having a structural unit represented by the following formula (2). In the following formula (2), the right end and the left end are bonding sites with other groups. Only one type of the carbodiimide compound may be used, or two or more types may be used in combination.

In the above formula (2), X represents an alkylene group, a group in which a substituent is bonded to an alkylene group, a cycloalkylene group, a group in which a substituent is bonded to a cycloalkylene group, an arylene group, or a group in which a substituent is bonded to an arylene group, and p represents an integer of 1 to 5. When there are multiple Xs, the multiple Xs may be the same or different.

In one preferred embodiment, at least one X is an alkylene group, a group having a substituent bonded to an alkylene group, a cycloalkylene group, or a group having a substituent bonded to a cycloalkylene group.

Commercially available examples of the above carbodiimide compounds include "Carbodilite V-02B", "Carbodilite V-03", "Carbodilite V-04K", "Carbodilite V-07", "Carbodilite V-09", "Carbodilite 10M-SP", and "Carbodilite 10M-SP (modified)" manufactured by Nisshinbo Chemical Inc., as well as "Stavaxol P", "Stavaxol P400", and "Hi-Kasil 510" manufactured by Rhein Chemie.

Examples of the above acid anhydrides include tetrahydrophthalic anhydride and alkylstyrene-maleic anhydride copolymers.

Commercially available products of the above acid anhydrides include "Rikacid TDA-100" manufactured by New Japan Chemical Co., Ltd.

The content of the curing agent relative to 100 parts by weight of the epoxy compound is preferably 70 parts by weight or more, more preferably 85 parts by weight or more, preferably 150 parts by weight or less, more preferably 120 parts by weight or less. When the content of the curing agent is equal to or more than the lower limit and equal to or less than the upper limit, the curing property is more excellent, the thermal dimensional stability is further improved, and the volatilization of the remaining unreacted components can be further suppressed.

In 100% by weight of the components excluding the inorganic filler and the solvent in the resin material, the total content of the compound X, the thermosetting compound, and the curing agent is preferably 40% by weight or more, more preferably 60% by weight or more, preferably 98% by weight or less, and more preferably 95% by weight or less. When the total content of the compound X, the thermosetting compound, and the curing agent is equal to or more than the lower limit and equal to or less than the upper limit, the curing property is more excellent and the thermal dimensional stability can be further improved.

[Curing accelerator]
The resin material includes a curing accelerator. The use of the curing accelerator further accelerates the curing speed. By quickly curing the resin material, the crosslinked structure in the cured product becomes uniform, and the number of unreacted functional groups is reduced, resulting in a high crosslink density. The curing accelerator is not particularly limited, and a conventionally known curing accelerator can be used. The curing accelerator may be used alone or in combination of two or more.

Examples of the curing accelerator include anionic curing accelerators such as imidazole compounds, cationic curing accelerators such as amine compounds, curing accelerators other than anionic and cationic curing accelerators such as phosphorus compounds and organometallic compounds, and radical curing accelerators such as peroxides.

The above imidazole compounds include 2-undecylimidazole, 2-heptadecylimidazole, 2-methylimidazole, 2-ethyl-4-methylimidazole, 2-phenylimidazole, 2-phenyl-4-methylimidazole, 1-benzyl-2-methylimidazole, 1-benzyl-2-phenylimidazole, 1,2-dimethylimidazole, 1-cyanoethyl-2-methylimidazole, 1-cyanoethyl-2-ethyl-4-methylimidazole, 1-cyanoethyl-2-undecylimidazole, 1-cyanoethyl-2-phenylimidazole, 1-cyanoethyl-2-undecylimidazole, 1-cyanoethyl-2-phenylimidazole, 1-cyanoethyl-2-undecylimidazolium trimellitate, and 1-cyanoethyl-2-phenylimidazolium trimethylate. Limellitate, 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-phenylimidazole isocyanuric acid adduct, 2-methylimidazole isocyanuric acid adduct, 2-phenyl-4,5-dihydroxymethylimidazole and 2-phenyl-4-methyl-5-dihydroxymethylimidazole.

Examples of the above amine compounds include diethylamine, triethylamine, diethylenetetramine, triethylenetetramine, and 4,4-dimethylaminopyridine.

Examples of the above phosphorus compounds include triphenylphosphine compounds.

Examples of the organometallic compounds include zinc naphthenate, cobalt naphthenate, tin octoate, cobalt octoate, cobalt bis(II) acetylacetonate, and cobalt tris(III) acetylacetonate.

Examples of the above peroxides include dicumyl peroxide and perhexyl 25B.

From the viewpoint of further reducing the curing temperature and effectively suppressing warping of the cured product, it is preferable that the curing accelerator contains the anionic curing accelerator, and it is more preferable that the curing accelerator contains the imidazole compound.

From the viewpoint of further suppressing the curing temperature and effectively suppressing warping of the cured product, the content of the anionic curing accelerator in 100% by weight of the curing accelerator is preferably 20% by weight or more, more preferably 50% by weight or more, even more preferably 70% by weight or more, and most preferably 100% by weight (total amount). Therefore, it is most preferable that the curing accelerator is the anionic curing accelerator.

When the thermosetting compound contains a radically curable compound such as the vinyl compound, the acrylate compound, and the styrene compound, radical curing proceeds, so it is preferable that the curing accelerator contains the radical curing accelerator.

The content of the curing accelerator is not particularly limited. The content of the curing accelerator is preferably 0.01% by weight or more, more preferably 0.05% by weight or more, preferably 5% by weight or less, more preferably 3% by weight or less, based on 100% by weight of the components in the resin material excluding the inorganic filler and the solvent. When the content of the curing accelerator is equal to or more than the lower limit and equal to or less than the upper limit, the resin material is cured efficiently. When the content of the curing accelerator is within a more preferred range, the storage stability of the resin material is further increased, and a better cured product is obtained.

[Thermoplastic resin]
The resin material preferably contains a thermoplastic resin. Examples of the thermoplastic resin include polyvinyl acetal resin, polyimide resin, phenoxy resin, and styrene-butadiene resin. The thermoplastic resin may be used alone or in combination of two or more kinds.

From the viewpoint of effectively lowering the dielectric tangent and effectively increasing the adhesion of metal wiring regardless of the curing environment, the thermoplastic resin is preferably a phenoxy resin. The use of phenoxy resin suppresses the deterioration of the embedding ability of the resin film into holes or irregularities in the circuit board and the non-uniformity of the inorganic filler. In addition, the use of phenoxy resin improves the dispersibility of the inorganic filler because the melt viscosity can be adjusted, and the resin composition or B-staged product is less likely to wet and spread into unintended areas during the curing process.

The phenoxy resin contained in the resin material is not particularly limited. Conventionally known phenoxy resins can be used as the phenoxy resin. Only one type of the phenoxy resin may be used, or two or more types may be used in combination.

Examples of the phenoxy resin include phenoxy resins having a skeleton such as a bisphenol A type skeleton, a bisphenol F type skeleton, a bisphenol S type skeleton, a biphenyl skeleton, a novolac skeleton, a naphthalene skeleton, and an imide skeleton.

Commercially available examples of the above phenoxy resins include "YP50", "YP55" and "YP70" manufactured by Nippon Steel & Sumitomo Metal Chemical Co., Ltd., and "1256B40", "4250", "4256H40", "4275", "YX6954BH30" and "YX8100BH30" manufactured by Mitsubishi Chemical Corporation.

From the viewpoint of improving handling properties, plating peel strength at low roughness, and adhesion between the insulating layer and the metal layer, it is preferable that the above thermoplastic resin is a polyimide resin (polyimide compound).

From the viewpoint of improving solubility, it is preferable that the polyimide compound is a polyimide compound obtained by a method of reacting a tetracarboxylic dianhydride with an aliphatic diamine compound.

Examples of the tetracarboxylic dianhydride include pyromellitic dianhydride, 3,3',4,4'-benzophenone tetracarboxylic dianhydride, 3,3',4,4'-biphenylsulfone tetracarboxylic dianhydride, 1,4,5,8-naphthalene tetracarboxylic dianhydride, 2,3,6,7-naphthalene tetracarboxylic dianhydride, 3,3',4,4'-biphenyl ether tetracarboxylic dianhydride, 3,3',4,4'-dimethyldiphenylsilane tetracarboxylic dianhydride, 3,3',4,4'-tetraphenylsilane tetracarboxylic dianhydride, 1,2,3,4-furan tetracarboxylic dianhydride, 4,4'-bis(3,4-dicarboxylic acid dianhydride, 1,2,3,4-furan tetracarboxylic dianhydride, 1,4,5,8-naphthalene tetracarboxylic dianhydride, 2,3,6,7-naphthalene tetracarboxylic dianhydride, 1,4,5,8 ... Examples of the dianhydride include 4,4'-bis(3,4-dicarboxyphenoxy)diphenyl sulfide dianhydride, 4,4'-bis(3,4-dicarboxyphenoxy)diphenyl sulfone dianhydride, 4,4'-bis(3,4-dicarboxyphenoxy)diphenylpropane dianhydride, 3,3',4,4'-perfluoroisopropylidenediphthalic dianhydride, bis(phthalic acid)phenylphosphine oxide dianhydride, p-phenylene-bis(triphenylphthalic acid) dianhydride, m-phenylene-bis(triphenylphthalic acid) dianhydride, bis(triphenylphthalic acid)-4,4'-diphenyl ether dianhydride, and bis(triphenylphthalic acid)-4,4'-diphenylmethane dianhydride.

Examples of the aliphatic diamine include dimer diamine. Examples of the dimer diamine include VERSAMINE 551 (product name, manufactured by BASF Japan, 3,4-bis(1-aminoheptyl)-6-hexyl-5-(1-octenyl)cyclohexene), VERSAMINE 552 (product name, manufactured by Cognix Japan, hydrogenated VERSAMINE 551), PRIAMINE 1075, and PRIAMINE 1074 (product names, all manufactured by Croda Japan).

The polyimide compound may have an acid anhydride structure, a maleimide structure, or a citraconic imide structure at the end. In this case, the polyimide compound can be reacted with an epoxy compound. By reacting the polyimide compound with an epoxy compound, the thermal dimensional stability of the cured product can be improved.

From the viewpoint of obtaining a resin material having even better storage stability, the weight average molecular weight of the above thermoplastic resin, the above polyimide resin and the above phenoxy resin is preferably 10,000 or more, more preferably 15,000 or more, preferably 100,000 or less, more preferably 50,000 or less.

The weight average molecular weights of the thermoplastic resin, the polyimide resin and the phenoxy resin indicate the weight average molecular weights in terms of polystyrene measured by gel permeation chromatography (GPC).

The contents of the thermoplastic resin, the polyimide resin, and the phenoxy resin are not particularly limited. In 100% by weight of the components excluding the inorganic filler and the solvent in the resin material, the content of the thermoplastic resin (when the thermoplastic resin is a polyimide resin or a phenoxy resin, the content of the polyimide resin or the phenoxy resin) is preferably 1% by weight or more, more preferably 2% by weight or more, preferably 30% by weight or less, more preferably 20% by weight or less. When the content of the thermoplastic resin is equal to or more than the lower limit and equal to or less than the upper limit, the resin material has good embedding properties in holes or irregularities in the circuit board. When the content of the thermoplastic resin is equal to or more than the lower limit, the formation of the resin film becomes easier, and a better insulating layer is obtained. When the content of the thermoplastic resin is equal to or less than the upper limit, the thermal expansion coefficient of the cured product becomes even lower. When the content of the thermoplastic resin is equal to or less than the upper limit, the surface roughness of the surface of the cured product becomes even smaller, and the adhesive strength between the cured product and the metal layer becomes even higher.

[solvent]
The resin material does not contain or contains a solvent. By using the solvent, the viscosity of the resin material can be controlled within a suitable range, and the coatability of the resin material can be improved. The solvent may be used to obtain a slurry containing the inorganic filler. Only one type of the solvent may be used, or two or more types may be used in combination.

Examples of the above solvents include acetone, methanol, ethanol, butanol, 2-propanol, 2-methoxyethanol, 2-ethoxyethanol, 1-methoxy-2-propanol, 2-acetoxy-1-methoxypropane, toluene, xylene, methyl ethyl ketone, N,N-dimethylformamide, methyl isobutyl ketone, N-methyl-pyrrolidone, n-hexane, cyclohexane, cyclohexanone, and naphtha, which is a mixture.

It is preferable that most of the solvent is removed when the resin composition is molded into a film. Therefore, the boiling point of the solvent is preferably 200°C or less, more preferably 180°C or less. The content of the solvent in the resin composition is not particularly limited. The content of the solvent can be changed as appropriate, taking into account the coatability of the resin composition, etc.

When the resin material is a B-stage film, the content of the solvent in 100% by weight of the B-stage film is preferably 1% by weight or more, more preferably 2% by weight or more, preferably 10% by weight or less, more preferably 5% by weight or less.

[Other ingredients]
For the purpose of improving impact resistance, heat resistance, resin compatibility, workability, and the like, the resin material may contain an organic filler, a leveling agent, a flame retardant, a coupling agent, a colorant, an antioxidant, an ultraviolet degradation inhibitor, a defoaming agent, a thickener, a thixotropy imparting agent, and the like.

Examples of the organic filler include particulate materials made of benzoxazine resin, benzoxazole resin, fluororesin, acrylic resin, and styrene resin. Examples of the fluororesin include polytetrafluoroethylene (PTFE). By using fluororesin particles as the organic filler, the relative dielectric constant of the cured product can be further reduced. The average particle size of the organic filler is preferably 1 μm or less. If the average particle size of the organic filler is equal to or less than the upper limit, the surface roughness after etching can be reduced and the plating peel strength can be increased, and the adhesion between the insulating layer and the metal layer can be further improved. The average particle size of the organic filler may be 50 nm or more.

The median diameter (d50) at 50% is used as the average particle size of the organic filler. The average particle size can be measured using a laser diffraction scattering particle size distribution measuring device.

Examples of the coupling agent include silane coupling agents, titanium coupling agents, and aluminum coupling agents. Examples of the silane coupling agent include vinyl silane, amino silane, imidazole silane, and epoxy silane.

(Resin film)
The resin composition described above is molded into a film to obtain a resin film (B-stage product/B-stage film). The resin material is preferably a resin film. The resin film is preferably a B-stage film.

The following methods can be used to form a resin composition into a film to obtain a resin film. An extrusion molding method in which a resin composition is melt-kneaded and extruded using an extruder, and then molded into a film using a T-die or circular die. A casting molding method in which a resin composition containing a solvent is cast into a film. Other conventionally known film molding methods. Extrusion molding and casting molding are preferred because they can be made thinner. Films include sheets.

The resin composition is molded into a film and then heated and dried for 1 to 10 minutes at, for example, 50°C to 150°C to a degree that does not cause excessive curing due to heat, to obtain a resin film that is a B-stage film.

The film-like resin composition that can be obtained by the drying process described above is called a B-stage film. The B-stage film is in a semi-cured state. The semi-cured material is not completely cured and curing can continue.

The resin film does not have to be a prepreg. If the resin film is not a prepreg, migration will not occur along the glass cloth or the like. In addition, when the resin film is laminated or precured, irregularities caused by the glass cloth will not occur on the surface.

The resin film can be used in the form of a laminated film comprising a metal foil or a base film and a resin film laminated on the surface of the metal foil or the base film. The metal foil is preferably a copper foil.

Examples of the base film of the laminated film include polyester resin films such as polyethylene terephthalate film and polybutylene terephthalate film, olefin resin films such as polyethylene film and polypropylene film, and polyimide resin films. The surface of the base film may be subjected to a release treatment as necessary.

From the viewpoint of controlling the degree of cure of the resin film more uniformly, the thickness of the resin film is preferably 5 μm or more and preferably 200 μm or less. When the resin film is used as an insulating layer of a circuit, the thickness of the insulating layer formed by the resin film is preferably equal to or greater than the thickness of the conductor layer (metal layer) that forms the circuit. The thickness of the insulating layer is preferably 5 μm or more and preferably 200 μm or less.

(Semiconductor device, printed wiring board, copper-clad laminate, and multilayer printed wiring board)
The above-mentioned resin material is suitably used for forming a molding resin in which a semiconductor chip is embedded in a semiconductor device.

The above resin material is preferably used as an insulating material. The above resin material is preferably used to form an insulating layer in a printed wiring board.

The above printed wiring board is obtained, for example, by heating and pressurizing the above resin material.

A laminated member having a metal layer on one or both sides can be laminated onto the resin film. A laminated structure can be suitably obtained, which includes a laminated member having a metal layer on its surface and a resin film laminated on the surface of the metal layer, and the resin film is the above-mentioned resin material. The method for laminating the resin film and the laminated member having the metal layer on its surface is not particularly limited, and a known method can be used. For example, the resin film can be laminated onto the laminated member having a metal layer on its surface while applying pressure with or without heating using a device such as a parallel plate press or a roll laminator.

The material of the metal layer is preferably copper.

The laminated component having the above-mentioned metal layer on its surface may be a metal foil such as copper foil.

The above resin material is preferably used to obtain a copper-clad laminate. An example of the copper-clad laminate is a copper-clad laminate having a copper foil and a resin film laminated on one surface of the copper foil.

The thickness of the copper foil of the copper-clad laminate is not particularly limited. The thickness of the copper foil is preferably within the range of 1 μm to 50 μm. In addition, in order to increase the adhesive strength between the cured product of the resin material and the copper foil, it is preferable that the copper foil has fine irregularities on its surface. The method of forming the irregularities is not particularly limited. Examples of the method of forming the irregularities include a formation method by treatment using a known chemical solution.

The above resin materials are preferably used to obtain multilayer substrates.

An example of the multilayer board is a multilayer board including a circuit board and an insulating layer laminated on the circuit board. The insulating layer of the multilayer board is formed from the resin material. The insulating layer of the multilayer board may also be formed from the resin film of the laminate film using a laminate film. The insulating layer is preferably laminated on the surface of the circuit board on which the circuits are provided. A portion of the insulating layer is preferably embedded between the circuits.

In the above multilayer substrate, it is preferable that the surface of the insulating layer opposite to the surface on which the circuit board is laminated is roughened.

The roughening treatment method may be any conventionally known roughening treatment method, and is not particularly limited. The surface of the insulating layer may be subjected to a swelling treatment before the roughening treatment.

It is also preferable that the multilayer substrate further comprises a copper plating layer laminated on the roughened surface of the insulating layer.

Another example of the multilayer board is a multilayer board comprising a circuit board, an insulating layer laminated on a surface of the circuit board, and copper foil laminated on the surface of the insulating layer opposite to the surface on which the circuit board is laminated. It is preferable that the insulating layer is formed by using a copper-clad laminate comprising copper foil and a resin film laminated on one surface of the copper foil, and curing the resin film. Furthermore, it is preferable that the copper foil is etched to form a copper circuit.

Another example of the multilayer board is a multilayer board including a circuit board and a plurality of insulating layers laminated on a surface of the circuit board. At least one of the insulating layers arranged on the circuit board is formed using the resin material. It is preferable that the multilayer board further includes a circuit laminated on at least one surface of the insulating layer formed using the resin film.

Among multilayer substrates, multilayer printed wiring boards require a low dielectric tangent and high insulation reliability from the insulating layer. The resin material of the present invention can effectively improve insulation reliability by lowering the dielectric tangent and improving adhesion and etching performance between the insulating layer and the metal layer. Therefore, the resin material of the present invention is suitable for use in forming an insulating layer in a multilayer printed wiring board.

The multilayer printed wiring board includes, for example, a circuit board, a plurality of insulating layers disposed on a surface of the circuit board, and a metal layer disposed between the plurality of insulating layers. At least one of the insulating layers is a cured product of the resin material.

Figure 1 is a cross-sectional view showing a schematic diagram of a multilayer printed wiring board using a resin material according to one embodiment of the present invention.

In the multilayer printed wiring board 11 shown in FIG. 1, a plurality of insulating layers 13-16 are laminated on the upper surface 12a of the circuit board 12. The insulating layers 13-16 are hardened layers. A metal layer 17 is formed on a portion of the upper surface 12a of the circuit board 12. Of the plurality of insulating layers 13-16, the insulating layers 13-15 other than the insulating layer 16 located on the outer surface opposite the circuit board 12 side have a metal layer 17 formed on a portion of the upper surface. The metal layer 17 is a circuit. The metal layer 17 is disposed between the circuit board 12 and the insulating layer 13, and between each of the laminated insulating layers 13-16. The lower metal layer 17 and the upper metal layer 17 are connected to each other by at least one of a via hole connection and a through hole connection not shown.

In the multilayer printed wiring board 11, the insulating layers 13 to 16 are formed from the cured product of the above-mentioned resin material. In this embodiment, the surfaces of the insulating layers 13 to 16 are roughened, so that fine holes (not shown) are formed in the surfaces of the insulating layers 13 to 16. The metal layer 17 also reaches the inside of the fine holes. In the multilayer printed wiring board 11, the width dimension (L) of the metal layer 17 and the width dimension (S) of the portion where the metal layer 17 is not formed can be reduced. In the multilayer printed wiring board 11, good insulation reliability is provided between the upper metal layer and the lower metal layer that are not connected by via hole connections and through hole connections (not shown).

(Roughening treatment and swelling treatment)
The resin material is preferably used to obtain a cured product to be subjected to roughening treatment or desmear treatment. The cured product also includes a pre-cured product that can be further cured.

In order to form fine irregularities on the surface of the cured product obtained by pre-curing the above resin material, the cured product is preferably subjected to a roughening treatment. Before the roughening treatment, the cured product is preferably subjected to a swelling treatment. After the pre-curing and before the roughening treatment, the cured product is preferably subjected to a swelling treatment, and further to curing after the roughening treatment. However, the cured product does not necessarily have to be subjected to a swelling treatment.

The swelling treatment may be carried out, for example, by treating the cured product with an aqueous solution or an organic solvent dispersion of a compound whose main component is ethylene glycol. The swelling liquid used in the swelling treatment generally contains an alkali as a pH adjuster. The swelling liquid preferably contains sodium hydroxide. Specifically, for example, the swelling treatment is carried out by treating the cured product with a 40% by weight aqueous solution of ethylene glycol at a treatment temperature of 30°C to 85°C for 1 to 30 minutes. The temperature of the swelling treatment is preferably within the range of 50°C to 85°C. If the temperature of the swelling treatment is too low, the swelling treatment takes a long time, and the adhesive strength between the cured product and the metal layer tends to be reduced.

In the above roughening treatment, a chemical oxidizing agent such as a manganese compound, a chromium compound, or a persulfate compound is used. These chemical oxidizing agents are used as an aqueous solution or an organic solvent dispersion solution after water or an organic solvent is added. The roughening liquid used in the roughening treatment generally contains an alkali as a pH adjuster or the like. The roughening liquid preferably contains sodium hydroxide.

The manganese compounds include potassium permanganate and sodium permanganate. The chromium compounds include potassium dichromate and potassium chromate anhydride. The persulfate compounds include sodium persulfate, potassium persulfate, and ammonium persulfate.

The arithmetic mean roughness Ra of the surface of the cured product is preferably 10 nm or more, preferably less than 300 nm, more preferably less than 200 nm, and even more preferably less than 150 nm. In this case, the adhesive strength between the cured product and the metal layer is increased, and even finer wiring is formed on the surface of the insulating layer. Furthermore, conductor loss can be suppressed, and signal loss can be kept low. The arithmetic mean roughness Ra is measured in accordance with JIS B0601:1994.

(Desmearing)
Through holes may be formed in the cured product obtained by pre-curing the resin material. In the multilayer board, etc., vias or through holes are formed as the through holes. For example, vias can be formed by irradiating a laser such as a _CO2 laser. The diameter of the via is not particularly limited, but is about 60 μm to 80 μm. Due to the formation of the through holes, smears, which are resin residues derived from the resin components contained in the cured product, are often formed at the bottom of the via.

In order to remove the smears, the surface of the cured product is preferably subjected to a desmear treatment. The desmear treatment may also serve as a roughening treatment.

In the desmear treatment, a chemical oxidizing agent such as a manganese compound, a chromium compound, or a persulfate compound is used, as in the roughening treatment. These chemical oxidizing agents are used as an aqueous solution or an organic solvent dispersion solution after water or an organic solvent is added. The desmear treatment liquid used in the desmear treatment generally contains an alkali. The desmear treatment liquid preferably contains sodium hydroxide.

By using the above resin material, the surface roughness of the desmeared cured material is sufficiently reduced.

The present invention will be specifically described below by giving examples and comparative examples. The present invention is not limited to the following examples.

The following materials were prepared:

(Compound X)
Compound X-1:
According to the following Synthesis Example 1, a compound X-1 (molecular weight 4000) represented by the following formula (X-1) was synthesized.

<Synthesis Example 1>
In a 500 mL eggplant flask, 90 g of toluene, 46 g of N-methyl-2-pyrrolidone (NMP), and 9 g of methanesulfonic acid were placed. Then, 15.6 g (80 mmol) of tricyclodecanediamine was added. Then, 17.7 g (60 mmol) of 3,3',4,4'-biphenyltetracarboxylic dianhydride was added little by little. Then, the eggplant flask was attached to a Dean-Stark apparatus and heated under reflux for 3.5 hours. In this way, a compound having an acid anhydride structure at the end and a plurality of imide skeletons was obtained. After removing the moisture discharged during condensation and returning to room temperature, 4.42 g (45 mmol) of maleic anhydride was added and stirred, and similarly heated to react. The organic layer was washed with a mixed solvent of water and ethanol, and the mixed solvent was removed to obtain a toluene solution. Then, isopropanol was added to the toluene solution to reprecipitate the product. Then, the mixture was dried in a vacuum oven to obtain compound X-1.

Compound X-2:
According to Synthesis Example 2 below, compound X-2 (molecular weight 4500) represented by the following formula (X-2) was synthesized. In the obtained compound X-2, the average proportion of the first skeleton derived from tricyclodecanediamine was 72 mol %, and the average proportion of the second skeleton derived from dimer diamine was 28 mol %, relative to 100 mol % of all structural units derived from diamine compounds. Note that the following formula (X-2) is an example of compound X-2 obtained in Synthesis Example 2, and compound X-2 is obtained as a mixture of compounds in which the positions of the amines are different.

<Synthesis Example 2>
In a 500 mL eggplant flask, 90 g of toluene, 46 g of N-methyl-2-pyrrolidone (NMP), and 7 g of methanesulfonic acid were placed. Then, 6.6 g (16 mmol) of dimer diamine ("PRIAMINE 1075" manufactured by Croda Japan) and 12.5 g (64 mmol) of tricyclodecane diamine were added. Then, 17.7 g (60 mmol) of 3,3',4,4'-biphenyltetracarboxylic dianhydride was added little by little. The eggplant flask was attached to a Dean-Stark apparatus and heated under reflux for 3.5 hours. In this way, a compound having amines at both ends and multiple imide skeletons was obtained. After removing the moisture discharged during condensation and returning to room temperature, 4.42 g (45 mmol) of maleic anhydride was added and stirred, and similarly heated to react. In this way, a compound having maleimide skeletons at both ends was obtained. The organic layer was washed with a mixed solvent of water and ethanol, and the mixed solvent was removed to obtain a toluene solution. Next, isopropanol was added to the toluene solution to reprecipitate the product, which was then dried in a vacuum oven to obtain compound X-2.

Compound X-3:
According to Synthesis Example 3 below, compound X-3 (molecular weight 4200) represented by the following formula (X-3) was synthesized. In the obtained compound X-3, the average proportion of the first skeleton derived from tricyclodecanediamine was 75 mol %, and the average proportion of the second skeleton derived from dimer diamine was 25 mol %, relative to 100 mol % of all structural units derived from diamine compounds. Note that the following formula (X-3) is an example of compound X-3 obtained in Synthesis Example 3, and compound X-3 is obtained as a mixture of compounds in which the positions of the amines are different.

<Synthesis Example 3>
In a 500 mL eggplant flask, 90 g of toluene, 46 g of N-methyl-2-pyrrolidone (NMP), and 7 g of methanesulfonic acid were placed. Next, 6.6 g (16 mmol) of dimer diamine (PRIAMINE 1075 manufactured by Croda Japan) and 9.9 g (64 mmol) of norbornane diamine (Pro-NBDA manufactured by Mitsui Fine Chemicals, Inc.) were added. Next, 15.9 g (54 mmol) of 3,3',4,4'-biphenyltetracarboxylic dianhydride and 1.5 g (6 mmol) of bicyclo[2.2.2]oct-7-ene-2,3,5,6-tetracarboxylic dianhydride were mixed and then added little by little. The eggplant flask was attached to the Queen-Stark apparatus and heated to reflux for 3.5 hours. In this way, a compound having amines at both ends and multiple imide skeletons was obtained. After removing the moisture discharged during condensation and returning to room temperature, 4.42 g (45 mmol) of maleic anhydride was added and stirred, and similarly heated to react. In this way, a compound having maleimide skeletons at both ends was obtained. The organic layer was washed with a mixed solvent of water and ethanol, and the mixed solvent was then removed to obtain a toluene solution of compound X-3.

(Compound Y not corresponding to compound X)
Compound Y-1:
According to the following Synthesis Example 4, compound Y-1 (molecular weight 3300) was synthesized.

<Synthesis Example 4>
In a 500 mL eggplant flask, 90 g of toluene, 46 g of N-methyl-2-pyrrolidone (NMP), and 9 g of methanesulfonic acid were placed. Then, 15.6 g (80 mmol) of tricyclodecanediamine was added. Then, 13.1 g (60 mmol) of pyromellitic dianhydride was added little by little. Then, the eggplant flask was attached to a Dean-Stark apparatus and heated under reflux for 3.5 hours. In this way, a compound having an acid anhydride structure at the end and a plurality of imide skeletons was obtained. After removing the moisture discharged during condensation and returning to room temperature, 4.42 g (45 mmol) of maleic anhydride was added and stirred, and similarly heated to react. The organic layer was washed with a mixed solvent of water and ethanol, and the mixed solvent was removed to obtain a toluene solution. Then, isopropanol was added to the toluene solution to perform reprecipitation of the product. Then, the mixture was dried in a vacuum oven to obtain compound Y-1.

Compound Y-2:
According to the following Synthesis Example 5, compound Y-2 (molecular weight 5100) was synthesized.

<Synthesis Example 5>
In a 500 mL eggplant flask, 90 g of toluene, 46 g of N-methyl-2-pyrrolidone (NMP), and 7 g of methanesulfonic acid were placed. Then, 6.6 g (16 mmol) of dimer diamine ("PRIAMINE 1075" manufactured by Croda Japan) and 12.5 g (64 mmol) of tricyclodecane diamine were added. Then, 31.3 g (60 mmol) of BisA-type acid dianhydride was added little by little. The eggplant flask was attached to a Dean-Stark apparatus and heated under reflux for 3.5 hours. In this way, a compound having amines at both ends and multiple imide skeletons was obtained. After removing the moisture discharged during condensation and returning to room temperature, 4.42 g (45 mmol) of maleic anhydride was added and stirred, and similarly heated and reacted. In this way, a compound having maleimide skeletons at both ends was obtained. The organic layer was washed with a mixed solvent of water and ethanol, and the mixed solvent was removed to obtain a toluene solution. Next, isopropanol was added to the toluene solution to reprecipitate the product, which was then dried in a vacuum oven to obtain compound Y-2.

The molecular weights of compounds X and Y synthesized in Synthesis Examples 1-5 were determined as follows.

GPC (Gel Permeation Chromatography) Measurement:
Using a high performance liquid chromatograph system manufactured by Shimadzu Corporation, measurements were performed at a column temperature of 40°C and a flow rate of 1.0 ml/min, with tetrahydrofuran (THF) as the developing medium. An "SPD-10A" was used as the detector, and two "KF-804L" columns (exclusion limit molecular weight 400,000) manufactured by Shodex Corporation were used in series. "TSK Standard Polystyrene" manufactured by Tosoh Corporation was used as the standard polystyrene, and a calibration curve was created using substances with weight average molecular weights Mw = 354,000, 189,000, 98,900, 37,200, 17,100, 9,830, 5,870, 2,500, 1,050, and 500, and the molecular weight was calculated.

The average ratio of each skeleton of compounds X-2 and X-3 synthesized in Synthesis Examples 2 and 3 was calculated from the signal area ratio of hydrogen atoms bonded to carbon atoms bonded to nitrogen atoms constituting each diamine skeleton by ¹ H-NMR measurement.

(thermosetting compound)
Biphenyl type epoxy compound ("NC-3000" manufactured by Nippon Kayaku Co., Ltd.)
Naphthalene-type epoxy compound ("ESN-475V" manufactured by Nippon Steel & Sumikin Chemical Co., Ltd.)
Resorcinol diglycidyl ether ("EX-201" manufactured by Nagase Chemtex Corporation)
Epoxy compound having a glycidylamine skeleton ("630" manufactured by Mitsubishi Chemical Corporation)
Epoxy compound having a polybutadiene skeleton ("PB3600" manufactured by Daicel Corporation)
Epoxy compound having an amide skeleton ("WHR-991S" manufactured by Nippon Kayaku Co., Ltd.)
Hyperbranched aliphatic epoxy compound (Nissan Chemical's "Foldi E101")
Maleimide compound 1 ("BMI-689" manufactured by Designer Molecules Inc.)
Maleimide compound 2 (N-alkyl bismaleimide compound, "BMI-1500" manufactured by Designer Molecules Inc.)
Maleimide compound 3 (N-alkyl bismaleimide compound, "BMI-1700" manufactured by Designer Molecules Inc.)
Maleimide compound 4 (manufactured by Daiwa Kasei Co., Ltd., "BMI-4100")
Maleimide compound 5 ("MIR-3000" manufactured by Nippon Kayaku Co., Ltd.)
Styrene compounds (Mitsubishi Gas Chemical's "OPE-2St-1200", radical curing compounds, styrene compounds having a phenylene ether skeleton)
Acrylate compound (Kyoeisha Chemical's "Light Acrylate DCP-A", a radical curing compound, abbreviated as "DCP-A" in the table)

(Inorganic filler)
Silica-containing slurry (75% silica by weight: Admatechs "SC4050-HOA", average particle size 1.0 μm, aminosilane treatment, cyclohexanone 25% by weight)

(Hardening agent)
Active ester compound 1-containing solution (DIC Corporation "EXB-9416-70BK", solid content 70% by weight)
Active ester compound 2-containing liquid (DIC Corporation "HPC-8150-62T", solid content 62% by weight)
Active ester compound 3-containing liquid (DIC Corporation "HPC-8000L-65T", solid content 65% by weight)
Active ester compound 4 ("EXB-8" manufactured by DIC Corporation, solid content 100% by weight)
Carbodiimide compound ("Carbodilite V-03" manufactured by Nisshinbo Chemical Co., Ltd., abbreviated as "V-03" in the table)
Phenol compound-containing liquid (DIC Corporation "LA-1356", solid content 60% by weight, phenol compound having an aminotriazine skeleton)

(Cure Accelerator)
Dimethylaminopyridine ("DMAP" manufactured by Wako Pure Chemical Industries, Ltd.)
2-Phenyl-4-methylimidazole ("2P4MZ" manufactured by Shikoku Chemical Industry Co., Ltd., anionic curing accelerator)
Dicumyl Peroxide

(thermoplastic resin)
Styrene butadiene resin ("Tuftec H1043" manufactured by Asahi Kasei Corporation, abbreviated as "H1043" in the table)
Unhydrogenated alicyclic/aromatic hydrocarbon resin ("Neoresin EP-140" manufactured by JXTG Corporation, abbreviated as "EP-140" in the table)
Polyimide compounds (polyimide resins):
A solution containing a polyimide compound (non-volatile content: 26.8% by weight), which is a reaction product of tetracarboxylic dianhydride and dimer diamine, was synthesized according to Synthesis Example 6 below.

<Synthesis Example 6>
In a reaction vessel equipped with a stirrer, a water divider, a thermometer and a nitrogen gas inlet tube, 300.0 g of tetracarboxylic dianhydride ("BisDA-1000" manufactured by SABIC Japan LLC) and 665.5 g of cyclohexanone were placed, and the solution in the reaction vessel was heated to 60 ° C. Then, 89.0 g of dimer diamine ("PRIAMINE 1075" manufactured by Croda Japan) and 54.7 g of 1,3-bisaminomethylcyclohexane (manufactured by Mitsubishi Gas Chemical Co., Ltd.) were dropped into the reaction vessel. Next, 121.0 g of methylcyclohexane and 423.5 g of ethylene glycol dimethyl ether were added to the reaction vessel, and the imidization reaction was carried out at 140 ° C. for 10 hours. In this way, a polyimide compound-containing solution (non-volatile content 26.8 wt%) was obtained. The molecular weight (weight average molecular weight) of the obtained polyimide compound was 20,000. The molar ratio of acid component/amine component was 1.04.

The molecular weight of the polyimide compound synthesized in Synthesis Example 6 was determined as follows.

GPC (Gel Permeation Chromatography) Measurement:
Using a high performance liquid chromatograph system manufactured by Shimadzu Corporation, measurements were performed at a column temperature of 40°C and a flow rate of 1.0 ml/min, with tetrahydrofuran (THF) as the developing medium. An "SPD-10A" was used as the detector, and two "KF-804L" columns (exclusion limit molecular weight 400,000) manufactured by Shodex Corporation were used in series. "TSK Standard Polystyrene" manufactured by Tosoh Corporation was used as the standard polystyrene, and a calibration curve was created using substances with weight average molecular weights Mw = 354,000, 189,000, 98,900, 37,200, 17,100, 9,830, 5,870, 2,500, 1,050, and 500, and the molecular weight was calculated.

(Examples 1 to 9 and Comparative Examples 1 to 5)
The components shown in Tables 1 to 3 below were mixed in the amounts (unit: parts by weight of solid content) shown in Tables 1 to 3 below, and stirred at room temperature until a homogeneous solution was obtained, to obtain a resin material.

Preparation of resin film:
The obtained resin material was applied to the release-treated surface of a release-treated PET film ("XG284" manufactured by Toray Industries, Inc., thickness 25 μm) using an applicator, and then dried for 2 minutes and 30 seconds in a gear oven at 100° C. to volatilize the solvent. In this way, a laminated film (a laminated film of a PET film and a resin film) was obtained in which a resin film (B-stage film) having a thickness of 40 μm was laminated on the PET film.

(evaluation)
(1) Dielectric loss tangent The obtained resin film was heated at 190° C. for 90 minutes to obtain a cured product. The obtained cured product was cut into a size of 2 mm in width and 80 mm in length, and 10 sheets were stacked together. The dielectric loss tangent was measured at room temperature (23° C.) and a frequency of 5.8 GHz by the cavity resonance method using a "Cavity Resonance Perturbation Dielectric Constant Measurement Device CP521" manufactured by Kanto Electronics Application Development Co., Ltd. and a "Network Analyzer N5224A PNA" manufactured by Keysight Technologies, Inc.

[Criteria for dielectric tangent]
○: Dielectric tangent is less than 2.9×10 ⁻³ ×: Dielectric tangent is 2.9×10 ⁻³ or more

(2) Thermal dimensional stability (average coefficient of linear expansion (CTE))
The resulting 40 μm thick resin film (B-stage film) was heated at 190° C. for 90 minutes, and the resulting cured product was cut into pieces measuring 3 mm x 25 mm. The average linear expansion coefficient (ppm/° C.) of the cut cured product from 25° C. to 150° C. was calculated using a thermomechanical analyzer ("EXSTAR TMA/SS6100" manufactured by SII NanoTechnology Inc.) under conditions of a tensile load of 33 mN and a heating rate of 5° C./min.

[Criteria for Average Linear Expansion Coefficient]
○○: Average linear expansion coefficient is 25 ppm/°C or less. ○: Average linear expansion coefficient is more than 25 ppm/°C and less than 29 ppm/°C. ×: Average linear expansion coefficient is more than 29 ppm/°C.

(3) Desmearing ability (ability to remove residues at the bottom of vias)
Lamination and semi-curing process:
The obtained resin film was vacuum laminated onto a CCL substrate ("E679FG" manufactured by Hitachi Chemical Co., Ltd.) and semi-cured by heating at 180° C. for 30 minutes. In this way, a laminate A in which a semi-cured resin film was laminated onto a CCL substrate was obtained.

Via formation:
A via (through hole) having a diameter of 60 μm at the top and a diameter of 40 μm at the bottom (bottom) was formed using a _CO2 laser (manufactured by Hitachi Via Mechanics Co., Ltd.) in the semi-cured resin film of the obtained laminate A. In this way, a laminate B was obtained in which the semi-cured resin film was laminated on the CCL substrate and the via (through hole) was formed in the semi-cured resin film.

Via bottom residue removal process:
(a) Swelling Treatment The obtained laminate B was placed in a swelling liquid (Swelling Dip Securigant P, manufactured by Atotech Japan) at 60° C. and shaken for 10 minutes. Thereafter, it was washed with pure water.

(b) Permanganate treatment (roughening treatment and desmear treatment)
The laminate B after the swelling treatment was placed in a roughening aqueous solution of potassium permanganate ("Concentrate Compact CP" manufactured by Atotech Japan) at 80° C. and was shaken for 30 minutes. Next, it was treated for 2 minutes using a cleaning solution ("Reduction Securigant P" manufactured by Atotech Japan) at 25° C., and then washed with pure water to obtain evaluation sample 1.

The bottom of the via of evaluation sample 1 was observed with a scanning electron microscope (SEM) and the maximum smear length from the wall surface of the via bottom was measured. The removability of the residue at the via bottom was evaluated according to the following criteria.

[Criteria for Removability of Residue at Via Bottom]
○○: The maximum smear length is less than 2 μm. ○: The maximum smear length is 2 μm or more and less than 5 μm. ×: The maximum smear length is 5 μm or more.

(4) Surface roughness after etching (surface roughness) and uniformity of surface roughness Lamination process and semi-curing treatment:
A double-sided copper-clad laminate (CCL substrate) (Hitachi Chemical Co., Ltd. "E679FG") was prepared. Both sides of the copper foil surface of this double-sided copper-clad laminate were immersed in MEC Co., Ltd.'s "Cz8101" to roughen the copper foil surface. On both sides of the roughened copper-clad laminate, the resin film (B stage film) side of the laminate film was laminated on the copper-clad laminate using Meiki Seisakusho Co., Ltd.'s "batch vacuum laminator MVLP-500-IIA" to obtain a laminated structure. The lamination conditions were reduced pressure for 30 seconds to make the air pressure 13 hPa or less, and then pressed at 100 ° C and a pressure of 0.4 MPa for 30 seconds. Then, the resin film was heated at 180 ° C for 30 minutes to semi-cure. In this way, a laminate in which a semi-cured resin film was laminated on a CCL substrate was obtained.

Roughening treatment:
(a) Swelling treatment:
The obtained laminate was placed in a swelling liquid (Swelling Dip Securigant P, manufactured by Atotech Japan) at 60° C. and shaken for 10 minutes, and then washed with pure water.

(b) Permanganate treatment (roughening treatment and desmear treatment):
The laminate after the swelling treatment was placed in a roughening aqueous solution of potassium permanganate ("Concentrate Compact CP" manufactured by Atotech Japan) at 80° C. and swung for 30 minutes. Next, the laminate was treated for 2 minutes using a cleaning solution ("Reduction Securigant P" manufactured by Atotech Japan) at 25° C., and then washed with pure water to obtain an evaluation sample.

Surface roughness measurement:
On the surface of the evaluation sample (roughened cured product), 10 areas of 94 μm × 123 μm were arbitrarily selected. For each of the 10 areas, the arithmetic mean roughness Ra was measured using a non-contact three-dimensional surface profiler (Veeco's "WYKO NT1100"). The following surface roughness was evaluated from the average value of the arithmetic mean roughness Ra measured at the 10 points, and the following surface roughness uniformity was evaluated from the absolute value of the difference between the maximum and minimum values of the arithmetic mean roughness Ra measured at the 10 points. The arithmetic mean roughness Ra was measured in accordance with JIS B0601:1994.

[Criteria for surface roughness after etching]
◯: The average value of the arithmetic mean roughness Ra is less than 50 nm Δ: The average value of the arithmetic mean roughness Ra is 50 nm or more and less than 80 nm ×: The average value of the arithmetic mean roughness Ra is 80 nm or more

[Criteria for judging uniformity of surface roughness after etching]
◯: The absolute value of the difference between the maximum and minimum values of the arithmetic mean roughness Ra is less than 10 nm. Δ: The absolute value of the difference between the maximum and minimum values of the arithmetic mean roughness Ra is 10 nm or more and less than 20 nm. ×: The absolute value of the difference between the maximum and minimum values of the arithmetic mean roughness Ra is 20 nm or more.

(5) Plating peel strength Lamination process and semi-curing treatment:
A 100 mm square double-sided copper-clad laminate (CCL substrate) (Hitachi Chemical Co., Ltd. "E679FG") was prepared. Both sides of the copper foil surface of this double-sided copper-clad laminate were immersed in MEC Co., Ltd.'s "Cz8101" to roughen the copper foil surface. Using Meiki Seisakusho Co., Ltd.'s "batch vacuum laminator MVLP-500-IIA", the resin film (B stage film) side of the laminate film was laminated on both sides of the roughened copper-clad laminate to obtain a laminated structure. The lamination conditions were reduced pressure for 30 seconds to make the air pressure 13 hPa or less, and then laminated at 100 ° C. and a pressure of 0.7 MPa for 30 seconds, and further pressed at a press pressure of 0.8 MPa and a press temperature of 100 ° C. for 60 seconds. Thereafter, with the PET film still attached, the resin film in the laminate structure was heated at 100° C. for 30 minutes, and then further heated at 180° C. for 30 minutes to semi-cure the resin film. Thereafter, the PET film was peeled off to obtain a laminate in which a semi-cured product of the resin film was laminated on the CCL substrate.

Roughening treatment:
(a) Swelling treatment:
The obtained laminate was placed in a swelling liquid (Swelling Dip Securigant P, manufactured by Atotech Japan) at 60° C. and shaken for 10 minutes, and then washed with pure water.

(b) Permanganate treatment (roughening treatment and desmear treatment):
The laminate after the swelling treatment was placed in a roughening aqueous solution of potassium permanganate ("Concentrate Compact CP" manufactured by Atotech Japan) at 80° C. and was shaken for 30 minutes. Next, the laminate was treated for 2 minutes using a cleaning solution ("Reduction Securigant P" manufactured by Atotech Japan) at 25° C., and then washed with pure water to perform a roughening treatment.

Electroless plating process:
The surface of the roughened cured product was treated with an alkaline cleaner at 60°C (Atotech Japan's "Cleaner Securigant 902") for 5 minutes and degreased. After cleaning, the cured product was treated with a pre-dip liquid at 25°C (Atotech Japan's "Pre-dip Neogant B") for 2 minutes. The cured product was then treated with an activator liquid at 40°C (Atotech Japan's "Activator Neogant 834") for 5 minutes to attach a palladium catalyst. Next, the cured product was treated with a reducing liquid at 30°C (Atotech Japan's "Reducer Neogant WA") for 5 minutes.

Next, the above cured material was placed in a chemical copper liquid (Atotech Japan's "Basic Printganth MSK-DK", "Copper Printganth MSK", "Stabilizer Printganth MSK", and "Reducer Cu") and electroless plating was carried out until the plating thickness reached approximately 0.5 μm. After electroless plating, an annealing treatment was carried out at a temperature of 120°C for 30 minutes to remove any remaining hydrogen gas. All steps up to the electroless plating step were carried out using 2 L of treatment liquid on a beaker scale, while the cured material was agitated.

Electrolytic plating process:
Next, electrolytic plating was performed on the electroless plated cured product until the plating thickness reached 25 μm. As electrolytic copper plating, a copper sulfate solution ("copper sulfate pentahydrate" manufactured by Wako Pure Chemical Industries, Ltd., "sulfuric acid" manufactured by Wako Pure Chemical Industries, Ltd., "basic leveler Cupracid HL" manufactured by Atotech Japan, and "corrector Cupracid GS" manufactured by Atotech Japan) was used, and electrolytic plating was performed by passing a current of 0.6 A/cm ² until the plating thickness reached about 25 μm. After the copper plating, the cured product was heated at 200° C. for 60 minutes to further cure the cured product. In this way, a cured product having a copper plating layer laminated on the upper surface was obtained.

Measurement of plating peel strength:
A total of six 10 mm-wide rectangular cuts were made at 5 mm intervals on the surface of the copper plating layer of the cured product having a copper plating layer laminated on the upper surface. The cured product having a copper plating layer laminated on the upper surface was set in a 90° peel tester (TE-3001 manufactured by Tester Sangyo Co., Ltd.), the end of the copper plating layer with the cut was picked up with a gripper, and the copper plating layer was peeled off by 20 mm to measure the peel strength (plating peel strength). The peel strength (plating peel strength) was measured for each of the six cut locations, and the average plating peel strength was calculated. The plating peel strength was judged according to the following criteria.

[Criteria for plating peel strength]
○○: The average value of the plating peel strength is 0.5 kgf/cm or more. ○: The average value of the plating peel strength is 0.45 kgf/cm or more and less than 0.5 kgf/cm. △: The average value of the plating peel strength is 0.35 kgf/cm or more and less than 0.45 kgf/cm. ×: The average value of the plating peel strength is less than 0.35 kgf/cm.

The composition and results are shown in Tables 1 to 3 below.

11: multilayer printed wiring board 12: circuit board 12a: upper surface 13-16: insulating layers 17: metal layer

Claims (20)

The composition includes a compound having a structure represented by the following formula (X) and a curing accelerator:
the compound is a thermosetting compound,
the compound is a compound having a maleimide skeleton,
The resin material , wherein the curing accelerator comprises an anionic curing accelerator or a radical curing accelerator .

In the formula (X), R is a group having an aliphatic ring, and R has a partial skeleton derived from a diamine compound other than dimer diamine , and n is a number of 1 or more. The resin material according to claim 1, wherein in formula (X), n is a number of 2 or more. The resin material according to claim 1 or 2 , wherein in formula (X), R has a partial skeleton derived from a dimer diamine. The resin material according to any one of claims 1 to 3, wherein the compound has a structure represented by the following formula (X1):

In the formula (X1), R1 is a group represented by the following formula (A1), (A2), (A3), (A4), (A5), or (A6); R2 is a group represented by the following formula (A7); and p and q each represent a number of 1 or more.

In the formula (A1), R1 to R10 each represent a hydrogen atom or a hydrocarbon group having 1 to 20 carbon atoms.

In the formula (A2), R1 to R10 each represent a hydrogen atom or a hydrocarbon group having 1 to 20 carbon atoms.

In the formula (A3), R1 to R10 each represent a hydrogen atom or a hydrocarbon group having 1 to 20 carbon atoms.

In the formula (A4), R1 to R18 each represent a hydrogen atom or a hydrocarbon group having 1 to 20 carbon atoms, and Q represents any group.

In the formula (A5), R1 to R8 each represent a hydrogen atom or a hydrocarbon group having 1 to 20 carbon atoms.

In the formula (A6), R1 to R12 each represent a hydrogen atom or a hydrocarbon group having 1 to 20 carbon atoms.

4. The resin material according to claim 1 , wherein in the compound, a nitrogen atom constituting the imide skeleton is bonded only to a carbon atom constituting the aliphatic skeleton. The resin material according to any one of claims 1 to 5 , wherein the compound has a maleimide skeleton at both ends. The resin material according to any one of claims 1 to 6 , wherein the compound has a weight average molecular weight of 1,000 or more and 100,000 or less. The compound has a structure represented by the following formula (Y):
The resin material according to any one of claims 1 to 7, wherein the number of repetitions of the structure represented by formula (X) is 10% or more and 90% or less of a total of 100% of the number of repetitions of the structure represented by formula ( Y) :

In the formula (Y), R1 represents a tetravalent organic group, R2 represents an organic group, and m represents a number of 1 or more. In the formula (Y), R1 does not have a skeleton derived from phthalimide,
The resin material according to claim 8 , wherein in formula (Y), R2 does not have a skeleton derived from phthalimide. The resin material according to claim 8 or 9 , wherein, in formula (Y), R1 does not have an aromatic skeleton. The present invention includes a thermosetting compound not having a structure represented by the following formula (100) and a curing agent,
The resin material according to any one of claims 1 to 10 , wherein the thermosetting compound not having a structure represented by the formula (100) includes an epoxy compound.

In the formula (100), R represents an organic group, and n represents a number of 1 or more. The resin material of claim 11 , wherein the hardener comprises an active ester compound. The resin material according to claim 12 , wherein at least one of the epoxy compound and the active ester compound has an imide skeleton or an amide skeleton. The resin material according to claim 11 , wherein the thermosetting compound not having a structure represented by formula (100) includes a radically curable compound. The resin material according to any one of claims 1 to 14 , further comprising an inorganic filler. The resin material according to claim 15 , wherein the content of the inorganic filler is 50% by weight or more based on 100% by weight of components excluding the solvent in the resin material. The resin material according to claim 15 or 16 , wherein the inorganic filler is silica. The resin material according to any one of claims 1 to 17 , which is a resin film. The resin material according to any one of claims 1 to 18 , which is used to form an insulating layer in a multilayer printed wiring board. A circuit board;
a plurality of insulating layers disposed on a surface of the circuit board;
a metal layer disposed between a plurality of the insulating layers;
A multilayer printed wiring board, wherein at least one of the insulating layers is a cured product of the resin material according to any one of claims 1 to 19 .

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