TWI863905B - Resin composition - Google Patents

Abstract

The present invention provides: a resin composition that can obtain a hardened material having a low dielectric tangent, excellent slag removal performance, and excellent adhesion to a conductive layer; a resin sheet containing the resin composition; a printed wiring board having an insulating layer formed using the resin composition; and a semiconductor device. The resin composition of the present invention comprises (A) an epoxy resin, (B) an active ester-based hardener, (C) a (meth)acrylate, and (D) an inorganic filler. The content of the component (D) is 70% by mass or more, when the non-volatile components in the resin composition are taken as 100% by mass. When the value obtained by dividing the mass of the component (A) by the epoxy equivalent is taken as a, and the value obtained by dividing the mass of the component (B) by the active ester equivalent is taken as b, b/a is 1.3 or more.

Description

Resin composition

The present invention relates to a resin composition, and further to a resin sheet, a printed wiring board and a semiconductor device containing the resin composition.

As a manufacturing technology for printed wiring boards, there is a known manufacturing method of a build-up method in which an insulating layer and a conductive layer are alternately stacked on an inner circuit substrate. The insulating layer is generally formed by curing a resin composition. For example, Patent Document 1 describes a resin composition containing (A) a free radical polymerizable compound, (B) an epoxy resin, (C) a curing agent, and (D) a roughening component. [Prior Technical Document] [Patent Document]

[Patent Document 1] Japanese Patent Application Publication No. 2014-034580

[Problems to be solved by the invention]

Although there are many resin compositions suitable for forming an insulating layer on an inner circuit substrate including the resin composition described in Patent Document 1, in recent years, there has been an increasing desire for an insulating layer having a lower dielectric tangent.

The inventors have studied and found that the cured product of the resin composition containing the material that reduces the dielectric tangent is not easy to obtain the adhesion with the conductor layer, and the glue residue removal property to ensure the conductivity is low. In recent years, when manufacturing multi-layer printed wiring boards, the cured product of the resin composition used to form the insulation layer is also required to have finer and higher density wiring, and in addition to low dielectric tangent, it is also required to have sufficient adhesion and glue residue removal properties, but the current situation cannot fully meet these requirements.

The subject of the present invention is to provide: a resin composition that can obtain a hardened material having a low dielectric tangent, excellent slag removal performance, and excellent adhesion to a conductive layer; a resin sheet containing the resin composition; a printed wiring board having an insulating layer formed using the resin composition; and a semiconductor device. [Means for solving the subject]

As a result of actively examining to solve the above-mentioned problem, the inventors of the present invention have found that the above-mentioned problem can be solved by the following resin composition, and thus completed the present invention. The resin composition includes (A) epoxy resin, (B) active ester hardener, (C) (meth) acrylate, and (D) inorganic filler, and the content of (D) inorganic filler and the ratio of (A) epoxy resin to (B) active ester hardener are set within a specific range. That is, the present invention includes the following content.

[1] A resin composition comprising (A) an epoxy resin, (B) an active ester hardener, (C) a (meth)acrylate, and (D) an inorganic filler, wherein the content of the component (D) is 70% by mass or more, when the non-volatile components in the resin composition are taken as 100% by mass, and when the value obtained by dividing the mass of the component (A) by the epoxy equivalent is a and the value obtained by dividing the mass of the component (B) by the active ester equivalent is b, b/a is 1.3 or more. [2] The resin composition of [1], wherein the component (C) has two or more (meth)acryloyl groups per molecule. [3] The resin composition of [1] or [2], wherein the component (C) has a cyclic structure. [4] The resin composition according to any one of [1] to [3], wherein the component (C) has a structure represented by the following formula (1): (In formula (1), ^R1 and ^R4 each independently represent an acryl group or a methacryl group, ^R2 and ^R3 each independently represent a divalent linking group, and ring A represents a divalent cyclic group.) [5] A resin composition as described in any one of [1] to [4], wherein component (A) comprises a liquid epoxy resin and a solid epoxy resin. [6] A resin composition as described in any one of [1] to [5], wherein the content of component (D) is 75% by mass or more when the non-volatile components in the resin composition are taken as 100% by mass. [7] A resin composition as described in any one of [1] to [6], wherein the content of component (C) is not less than 1 mass % and not more than 20 mass % when the resin component in the resin composition is set to 100 mass %. [8] A resin composition as described in any one of [1] to [7], which is used for insulation purposes. [9] A resin composition as described in any one of [1] to [8], which is used for forming an insulating layer. [10] A resin composition as described in any one of [1] to [9], which is used for forming an insulating layer for forming a conductive layer. [11] A resin composition as described in any one of [1] to [10], which is used for sealing a semiconductor chip. [12] A resin sheet comprising a support and a resin composition layer comprising a resin composition as described in any one of [1] to [11] and disposed on the support. [13] A printed wiring board comprising an insulating layer formed of a cured product of the resin composition as described in any one of [1] to [11]. [14] A semiconductor device comprising the printed wiring board as described in [13]. [Effects of the Invention]

According to the present invention, there can be provided: a resin composition which can obtain a hardened product having a low dielectric tangent, excellent slag removal performance, and excellent adhesion to a conductive layer; a resin sheet containing the resin composition; a printed wiring board having an insulating layer formed using the resin composition; and a semiconductor device.

The following shows the embodiments and examples to explain the present invention in detail. However, the present invention is not limited to the embodiments and examples listed below, and can be implemented with any changes without departing from the scope of the patent application of the present invention and its equivalent scope.

[Resin composition] The resin composition of the present invention is a resin composition comprising (A) epoxy resin, (B) active ester hardener, (C) (meth)acrylate, and (D) inorganic filler, wherein the content of component (D) is 70% by mass or more when the non-volatile components in the resin composition are taken as 100% by mass, and when the value obtained by dividing the mass of component (A) by the epoxy equivalent is taken as a, and the value obtained by dividing the mass of component (B) by the active ester equivalent is taken as b, b/a is 1.3 or more.

By using such a resin composition, a hardened material having a low dielectric tangent, excellent slag removal properties, and excellent adhesion to a conductive layer can be obtained.

The resin composition is composed of components (A) to (D), and may further include any component. Examples of the arbitrary component include (E) thermoplastic resin, (F) hardener, (G) hardening accelerator, (H) polymerization initiator, and (I) other additives. The following is a detailed description of each component contained in the resin composition of the present invention.

<(A) Epoxy resin> Examples of (A) epoxy resin include biphenylene type epoxy resin, bisphenol A type epoxy resin, bisphenol F type epoxy resin, bisphenol S type epoxy resin, bisphenol AF type epoxy resin, dicyclopentadiene type epoxy resin, trisphenol type epoxy resin, naphthol novolac type epoxy resin, phenol novolac type epoxy resin, tert-butyl-catechol type epoxy resin, naphthalene type epoxy resin, naphthol type epoxy resin, anthracene type epoxy resin, The epoxy resin may be a glycidylamine type epoxy resin, a glycidyl ester type epoxy resin, a cresol novolac type epoxy resin, a biphenyl type epoxy resin, a chain aliphatic epoxy resin, an epoxy resin having a butadiene structure, an alicyclic epoxy resin, a heterocyclic epoxy resin, an epoxy resin containing a spiro ring, an oxime type epoxy resin, an oxime dimethanol type epoxy resin, a naphthyl ether type epoxy resin, a trihydroxymethyl type epoxy resin, a tetraphenylethane type epoxy resin, etc. The epoxy resin may be used alone or in combination of two or more.

The resin composition preferably includes an epoxy resin having two or more epoxy groups in one molecule as the epoxy resin (A). From the viewpoint of significantly obtaining the desired effect of the present invention, the proportion of the epoxy resin having two or more epoxy groups in one molecule is preferably 50% by mass or more, more preferably 60% by mass or more, and particularly preferably 70% by mass or more, relative to 100% by mass of the non-volatile component of the epoxy resin (A).

Epoxy resins include epoxy resins that are liquid at 20°C (hereinafter referred to as "liquid epoxy resins") and epoxy resins that are solid at 20°C (hereinafter referred to as "solid epoxy resins"). In the resin composition, (A) epoxy resin may contain only liquid epoxy resin or only solid epoxy resin, but preferably a combination of liquid epoxy resin and solid epoxy resin is contained. By using a liquid epoxy resin and a solid epoxy resin in combination as the (A) epoxy resin, sufficient flexibility can be obtained when used in the form of a resin sheet, and the fracture strength of the cured product of the resin composition can be improved.

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

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

Specific examples of liquid epoxy resins include "HP4032", "HP4032D", and "HP4032SS" (naphthalene-based epoxy resins) manufactured by DIC Corporation; "828US", "jER828EL", "825", and "EPICOTE" manufactured by Mitsubishi Chemical Corporation. "828EL" (bisphenol A type epoxy resin); "jER807" and "1750" (bisphenol F type epoxy resin) manufactured by Mitsubishi Chemical; "jER152" (phenol novolac type epoxy resin) manufactured by Mitsubishi Chemical; "630" and "630LSD" (glycidylamine type epoxy resin) manufactured by Mitsubishi Chemical; "ZX1059" (a mixture of bisphenol A type epoxy resin and bisphenol F type epoxy resin) manufactured by Nippon Steel & Sumitomo Chemical; "EX-721" (glycidyl ester type epoxy resin) manufactured by NAGASE CHEMTEX; "CELOXIDE "2021P" manufactured by DAICEL (epoxy resin with an ester skeleton); "PB-3600" manufactured by DAICEL (epoxy resin with a butadiene structure); "ZX1658" and "ZX1658GS" manufactured by Nippon Steel & Sumitomo Metal Chemicals (liquid 1,4-glycidylcyclohexane type epoxy resins). These may be used alone or in combination of two or more.

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

As the solid epoxy resin, preferred are bixylene type epoxy resins, naphthalene type epoxy resins, naphthalene type tetrafunctional epoxy resins, cresol novolac type epoxy resins, dicyclopentadiene type epoxy resins, trisphenol type epoxy resins, naphthol type epoxy resins, biphenyl type epoxy resins, naphthyl ether type epoxy resins, anthracene type epoxy resins, bisphenol A type epoxy resins, bisphenol AF type epoxy resins, and tetraphenylethane type epoxy resins, and more preferred are naphthol type epoxy resins and naphthalene type epoxy resins.

Specific examples of solid epoxy resins include "HP4302H" (naphthalene-based epoxy resin) manufactured by DIC Corporation; "HP-4700" and "HP-4710" (naphthalene-based tetrafunctional epoxy resin) manufactured by DIC Corporation; "N-690" (cresol novolac-based epoxy resin) manufactured by DIC Corporation; "N-695" (cresol novolac-based epoxy resin) manufactured by DIC Corporation; "HP-7200", "HP-7200HH", "HP-7200HH" and "HP-7200HH" manufactured by DIC Corporation. 0H" (dicyclopentadiene type epoxy resin); "EXA-7311", "EXA-7311-G3", "EXA-7311-G4", "EXA-7311-G4S", "HP6000" (naphthyl ether type epoxy resin) manufactured by DIC Corporation; "EPPN-502H" (trisphenol type epoxy resin) manufactured by Nippon Kayaku Co., Ltd.; "NC7000L" (naphthol novolac epoxy resin) manufactured by Nippon Kayaku Co., Ltd.; "NC3000H" manufactured by Nippon Kayaku Co., Ltd., "NC3000", "NC3000L", "NC3100" (biphenyl type epoxy resin); "ESN475V" manufactured by Nippon Steel & Sumitomo Chemical Co., Ltd. (naphthalene type epoxy resin); "ESN485" manufactured by Nippon Steel & Sumitomo Chemical Co., Ltd. (naphthol novolac type epoxy resin); "YX4000H", "YX4000", "YL6121" (biphenyl type epoxy resin) manufactured by Mitsubishi Chemical Corporation; "YX4000HK" (xylenol type epoxy resin) manufactured by Mitsubishi Chemical Corporation "YX8800" manufactured by Mitsubishi Chemical (anthracene type epoxy resin); "PG-100" and "CG-500" manufactured by Osaka Gas Chemical; "YL7760" manufactured by Mitsubishi Chemical (bisphenol AF type epoxy resin); "YL7800" manufactured by Mitsubishi Chemical (fluorene type epoxy resin); "jER1010" manufactured by Mitsubishi Chemical (solid bisphenol A type epoxy resin); "jER1031S" manufactured by Mitsubishi Chemical (tetraphenylethane type epoxy resin), etc. These may be used alone or in combination of two or more.

When a liquid epoxy resin and a solid epoxy resin are used in combination as the epoxy resin (A), the mass ratio of the liquid epoxy resin: the solid epoxy resin is preferably 1:1 to 1:20, more preferably 1:1.5 to 1:15, and particularly preferably 1:2 to 1:10. By making the mass ratio of the liquid epoxy resin to the solid epoxy resin within this range, the desired effect of the present invention can be significantly obtained. Furthermore, when it is usually used in the form of a resin sheet, it retains moderate adhesion. And when it is usually used in the form of a resin sheet, it obtains sufficient flexibility and improves handling. Furthermore, a hardened material with sufficient breaking strength can usually be obtained.

(A) The epoxy equivalent of the epoxy resin is preferably 50 g/eq. to 5000 g/eq., more preferably 50 g/eq. to 3000 g/eq., still more preferably 80 g/eq. to 2000 g/eq., and still more preferably 110 g/eq. to 1000 g/eq. By being within this range, the crosslinking density of the cured product of the resin composition can be sufficient and an insulating layer with a small surface roughness can be formed. The epoxy equivalent is the mass of the epoxy resin containing 1 equivalent of epoxy group. The epoxy equivalent can be measured according to JIS K7236.

(A) The weight average molecular weight (Mw) of the epoxy resin is preferably 100-5000, more preferably 250-3000, and even more preferably 400-1500, from the viewpoint of significantly obtaining the desired effect of the present invention. The weight average molecular weight of the resin is measured as a polystyrene-converted value by gel permeation chromatography (GPC).

(A) The content of epoxy resin is preferably 1% by mass or more, more preferably 5% by mass or more, and even more preferably 8% by mass or more, based on the viewpoint of obtaining an insulating layer showing good mechanical strength and insulation reliability, when the non-volatile components in the resin composition are set to 100% by mass. The upper limit of the content of epoxy resin is preferably 25% by mass or less, more preferably 20% by mass or less, and particularly preferably 15% by mass or less, as long as the expected effect of the present invention can be significantly obtained. In addition, in the present invention, the content of each component in the resin composition is the value when the non-volatile components in the resin composition are set to 100% by mass, unless otherwise specified.

<(B) Active ester hardener> The resin composition contains (B) active ester hardener. When an active ester hardener is used, the dielectric tangent can usually be reduced, but on the other hand, the slag removal property is poor. However, the resin composition of the present invention contains component (C) and a specific amount of component (D), and the ratio of component (A) to component (B) is adjusted within a specific range, so that the dielectric tangent can be reduced and a hardened material with excellent slag removal property and adhesion can be obtained.

As (B) active ester curing agent, it is generally preferred to use a compound having two or more highly reactive ester groups in one molecule, such as phenol esters, thiophenol esters, N-hydroxylamine esters, and esters of heterocyclic hydroxyl compounds. The active ester curing agent is preferably obtained by a condensation reaction of a carboxylic acid compound and/or a thiocarboxylic acid compound with a hydroxyl compound and/or a thiol compound. In particular, from the viewpoint of improving heat resistance, an active ester curing agent obtained from a carboxylic acid compound and a hydroxyl compound is preferred, and an active ester curing agent obtained from a carboxylic acid compound and a phenol compound and/or a naphthol compound is more preferred. Examples of carboxylic acid compounds include benzoic acid, acetic acid, succinic acid, maleic acid, itaconic acid, phthalic acid, isophthalic acid, terephthalic acid, pyromellitic acid, and the like. Examples of phenolic compounds or naphthol compounds include hydroquinone, resorcinol, bisphenol A, bisphenol F, bisphenol S, phenolphthalein, methylated bisphenol A, methylated bisphenol F, methylated bisphenol S, phenol, o-cresol, m-cresol, p-cresol, catechol, α-naphthol, β-naphthol, 1,5-dihydroxynaphthalene, 1,6-dihydroxynaphthalene, 2,6-dihydroxynaphthalene, dihydroxybenzophenone, trihydroxybenzophenone, tetrahydroxybenzophenone, phloroglucin, pyrogallol, dicyclopentadiene-type diphenol compounds, and phenol novolac. Here, the so-called "dicyclopentadiene-type diphenol compound" refers to a diphenol compound obtained by condensing two molecules of phenol into one molecule of dicyclopentadiene.

Specifically, preferred are dicyclopentadiene type active ester hardeners, active ester hardeners containing naphthalene structures, active ester hardeners containing acetylated phenol novolacs, and active ester hardeners containing benzoylated phenol novolacs. Among them, active ester hardeners containing naphthalene structures and dicyclopentadiene type active ester hardeners are more preferred, and dicyclopentadiene type active ester hardeners are still more preferred. As dicyclopentadiene type active ester hardeners, active ester hardeners containing dicyclopentadiene type diphenol structures are preferred. The so-called "dicyclopentadiene type diphenol structure" refers to a divalent structural unit consisting of phenylene-dicyclopentylene-phenylene.

As for (B) commercially available active ester hardeners, examples of active ester hardeners containing a dicyclopentadiene-type diphenol structure include "EXB9451" (manufactured by DIC Corporation, active ester equivalent 223 g/eq.), "EXB9460" (manufactured by DIC Corporation, active ester equivalent 223 g/eq.), "EXB9460S" (manufactured by DIC Corporation, active ester equivalent 223 g/eq.), "HPC-8000-65T" (manufactured by DIC Corporation, active ester equivalent 223 g/eq.), "HPC-8000-65TM" (manufactured by DIC Corporation, active Examples of active ester hardeners containing naphthalene include "EXB-8100L-65T" (DIC, active ester equivalent 234 g/eq.), "EXB-8150L-60T" (DIC, active ester equivalent 226 g/eq.), "EXB-9416-70BK" (DIC, active ester equivalent 274 g/eq.), "PC1300-02" (AIR WATER Co., Ltd., active ester equivalent 200 g/eq.); as a phosphorus-containing active ester-based hardener, it is listed as "EXB9401" (manufactured by DIC Corporation, active ester equivalent 307 g/eq.); as an active ester-based hardener of acetylated phenol novolac, it is listed as "DC808" (manufactured by Mitsubishi Chemical Corporation, active ester equivalent 149 g/eq.); as an active ester-based hardener of benzoylated phenol novolac, it is listed as "YLH1026" (manufactured by Mitsubishi Chemical Corporation), "YLH1030" (manufactured by Mitsubishi Chemical Corporation), "YLH1048" (manufactured by Mitsubishi Chemical Corporation), etc.

(B) The active ester equivalent of the active ester hardener is preferably 50 g/eq. to 500 g/eq., more preferably 50 g/eq. to 400 g/eq., and even more preferably 100 g/eq. to 300 g/eq., from the viewpoint of reducing the dielectric tangent and obtaining a hardened material with excellent adhesion. The active ester equivalent is the mass of the active ester hardener containing 1 equivalent of active ester groups.

The value obtained by dividing the mass of component (A) by the epoxy equivalent is set to a. The value "a" represents the equivalent number (eq.) of the epoxy group contained in component (A). In addition, the value obtained by dividing the mass of component (B) by the active ester group equivalent is set to b. The value "b" represents the equivalent number (eq.) of the active ester group contained in component (B). In this case, b/a is greater than 1.3, preferably greater than 1.35, and more preferably greater than 1.4. The upper limit is preferably less than 5, more preferably less than 3, and more preferably less than 2. By adjusting the amount ratio of component (A) and component (B) so that b/a is within this range, the dielectric tangent can be reduced and a cured product with excellent adhesion can be obtained. Here, when the resin composition contains two or more (A) components, the above a is the total value of all values obtained by dividing the mass of each epoxy resin present in the resin composition by the value of each epoxy equivalent. And when the resin composition contains two or more (B) components, the above b is the total value of all values obtained by dividing the mass of each active ester-based curing agent present in the resin composition by the value of each active ester group equivalent.

The content of the active ester curing agent (B) is preferably 1% by mass or more, more preferably 3% by mass or more, and more preferably 5% by mass or more, when the non-volatile components in the resin composition are 100% by mass. The upper limit is preferably 30% by mass or less, more preferably 20% by mass or less, and more preferably 15% by mass or less. By making the content of the component (B) within this range, the dielectric tangent can be reduced and a cured product with excellent adhesion can be obtained.

<(C) (meth) acrylate> The resin composition contains (C) (meth) acrylate. By containing (C) (meth) acrylate in the resin composition, the dielectric tangent can be reduced and a cured product with excellent slag removal can be obtained. By adjusting the amount ratio of the (A) component and the (B) component to be within a specific range, the dielectric tangent can be reduced and a cured product with excellent adhesion can be obtained, but since there is a tendency for poor slag removal, in the present invention, by containing the (C) component in the resin composition, the slag removal can also be improved. Herein, the term "(meth) acrylic acid" includes acrylic acid and methacrylic acid and combinations thereof.

From the viewpoint of obtaining a cured product with reduced dielectric tangent and excellent scum removal properties, (C) (meth)acrylate preferably has two or more (meth)acryl groups per molecule. The term "(meth)acryl group" includes an acryl group and a methacryl group and a combination thereof.

From the viewpoint of obtaining a cured product with reduced dielectric tangent and excellent scum removal properties, (C) (meth)acrylate preferably has a cyclic structure. As the cyclic structure, a divalent cyclic group is preferably used. As the divalent cyclic group, it can be any one of a cyclic group containing an alicyclic structure and a cyclic group containing an aromatic ring structure. Among them, from the viewpoint of significantly obtaining the desired effect of the present invention, a cyclic group containing an alicyclic structure is preferred.

From the viewpoint of remarkably obtaining the expected effects of the present invention, the divalent cyclic group is preferably 3-membered or more, more preferably 4-membered or more, and even more preferably 5-membered or more, and preferably 20-membered or less, more preferably 15-membered or less, and even more preferably 10-membered or less. The divalent cyclic group may be a monocyclic structure or a polycyclic structure.

The ring in the divalent cyclic group may have a skeleton composed of heteroatoms in addition to carbon atoms. Examples of heteroatoms include oxygen atoms, sulfur atoms, and nitrogen atoms, preferably oxygen atoms. The ring may have one heteroatom or two or more heteroatoms.

Specific examples of the divalent cyclic group include the following divalent groups (i) to (xi). Among them, the divalent cyclic group is preferably (x) or (xi). [Chemistry 2]

The divalent cyclic group may have a substituent. Examples of such substituents include a halogen atom, an alkyl group, an alkoxy group, an aryl group, an arylalkyl group, a silyl group, an acyl group, an acyloxy group, a carboxyl group, a sulfo group, a cyano group, a nitro group, a hydroxyl group, a hydroxyl group, an oxo group, and the like, preferably an alkyl group.

The (meth)acryloyl group may be directly bonded to the divalent cyclic group or may be bonded via a divalent linking group. Examples of the divalent linking group include an alkylene group, an alkenylene group, an arylene group, a heteroarylene group, -C(=O)O-, -O-, -NHC(=O)-, -NC(=O)N-, -NHC(=O)O-, -C(=O)-, -S-, -SO-, -NH-, etc., and may also be a group combining a plurality of these groups. The alkylene group is preferably an alkylene group having 1 to 10 carbon atoms, more preferably an alkylene group having 1 to 6 carbon atoms, and even more preferably an alkylene group having 1 to 5 carbon atoms or an alkylene group having 1 to 4 carbon atoms. The alkylene group may be any of a straight chain, a branched group, and a cyclic group. Examples of such alkylene groups include methylene, ethylene, propylene, butylene, pentylene, hexylene, and 1,1-dimethylethylene, and methylene, ethylene, and 1,1-dimethylethylene are preferred. Alkenylene groups are preferably alkenylene groups having 2 to 10 carbon atoms, more preferably alkenylene groups having 2 to 6 carbon atoms, and still more preferably alkenylene groups having 2 to 5 carbon atoms. Arylene groups and heteroaryl groups are preferably arylene groups or heteroaryl groups having 6 to 20 carbon atoms, and more preferably arylene groups or heteroaryl groups having 6 to 10 carbon atoms. Alkylene groups are preferred as divalent linking groups, and methylene and 1,1-dimethylethylene are preferred.

(C) (meth)acrylate is preferably represented by the following formula (1). (In formula (1), ^R1 and ^R4 each independently represent an acryloyl group or a methacryloyl group, ^R2 and ^R3 each independently represent a divalent linking group, and ring A represents a divalent cyclic group)

^R1 and ^R4 each independently represent an acryl group or a methacryl group, preferably an acryl group.

^R2 and ^R3 each independently represent a divalent linking group. The divalent linking group is the same as the above-mentioned divalent linking group.

Ring A represents a divalent cyclic group. Ring A is the same as the divalent cyclic group described above.

Ring A may have a substituent. The substituent is the same as the substituent that the above-mentioned divalent cyclic group may have.

Specific examples of component (C) are shown below, but the present invention is not limited thereto.

As the component (C), a commercially available product may be used, for example, "A-DOG" manufactured by Shin-Nakamura Chemical Industry Co., Ltd., "DCP-A" manufactured by Kyoeisha Chemical Co., Ltd. The component (C) may be used alone or in combination of two or more.

The content of the component (C) is preferably 1% by mass or more, more preferably 3% by mass or more, and more preferably 5% by mass or more, based on the viewpoint of significantly obtaining the effect of the present invention, when the resin component in the resin composition is set to 100% by mass. The upper limit is preferably 20% by mass or less, more preferably 18% by mass or less, and more preferably 15% by mass or less, or 10% by mass or less. The "resin component" of the resin composition refers to the component excluding the (D) inorganic filler in the non-volatile matter contained in the resin composition.

<(D) Inorganic filler> The resin composition contains (D) inorganic filler. The content of (D) inorganic filler is preferably 70% by mass or more, more preferably 73% by mass or more, and more preferably 75% by mass or more, preferably 90% by mass or less, more preferably 85% by mass or less, and more preferably 80% by mass or less, based on the viewpoint of reducing dielectric tangent and improving slag removal performance, when the non-volatile components in the resin composition are set to 100% by mass. If the content of inorganic filler is 70% by mass or more, the adhesion tends to be reduced. However, in the resin composition of the present invention, since the ratio of the amount of (A) component to (B) component is adjusted to a specific range, the dielectric tangent can be reduced, and at the same time, a cured product with excellent slag removal performance and adhesion can be obtained.

Inorganic compounds are used as the material of the inorganic filler. Examples of the inorganic filler material include silicon oxide, aluminum oxide, glass, cordierite, silicon oxide, barium sulfate, barium carbonate, talc, clay, mica powder, zinc oxide, hydrotalcite, boehmite, aluminum hydroxide, magnesium hydroxide, calcium carbonate, magnesium carbonate, magnesium oxide, boron nitride, aluminum nitride, manganese nitride, aluminum borate, strontium carbonate, strontium titanate, calcium titanate, magnesium titanate, bismuth titanate, titanium oxide, zirconium oxide, barium titanate, barium zirconate, barium zirconate, calcium zirconate, zirconium phosphate, and zirconium tungstate phosphate. Among them, silicon oxide is particularly preferred. Examples of silicon oxide include amorphous silicon oxide, molten silicon oxide, crystalline silicon oxide, synthetic silicon oxide, hollow silicon oxide, etc. Preferably, the silicon oxide is spherical silicon oxide. (D) The inorganic filler may be used alone or in combination of two or more.

Examples of commercially available products of (D) inorganic fillers include "UFP-30" manufactured by Denka Kagaku Kogyo Co., Ltd.; "SP60-05" and "SP507-05" manufactured by Nippon Steel & Sumitomo Metal Materials Corporation; "YC100C", "YA050C", "YA050C-MJE", and "YA010C" manufactured by ADMATECHS; "UFP-30" manufactured by DENKA Corporation; "SILFIL NSS-3N", "SILFIL NSS-4N", and "SILFIL NSS-5N" manufactured by Tokuyama Corporation; "SC2500SQ", "SO-C4", "SO-C2", and "SO-C1" manufactured by ADMATECHS; and the like.

(D) The average particle size of the inorganic filler is preferably 0.01 μm or more, more preferably 0.05 μm or more, particularly preferably 0.1 μm or more, preferably 5 μm or less, more preferably 2 μm or less, and even more preferably 1 μm or less, from the viewpoint of significantly obtaining the desired effect of the present invention.

The average particle size of (D) inorganic fillers can be measured by laser diffraction/scattering method based on Mie scattering theory. Specifically, a laser diffraction particle size distribution measuring device can be used to make a particle size distribution of the inorganic filler based on volume, and the median diameter can be used for measurement. The measurement sample can preferably be made by measuring 100 mg of inorganic filler and 10 g of methyl ethyl ketone in a vial and dispersing them ultrasonically for 10 minutes. The sample is measured using a laser diffraction particle size distribution measuring device, and the wavelength of the light source is set to blue and red. The volume-based particle size distribution of (D) inorganic fillers is measured by flow cell method, and the average particle size is calculated from the obtained particle size distribution as the median diameter. An example of a laser diffraction particle size distribution measuring device is "LA-960" manufactured by Horiba, Ltd.

(D) The specific surface area of the inorganic filler is preferably 1 m ² /g or more, more preferably 2 m ² /g or more, and particularly preferably 3 m ² /g or more, from the viewpoint of significantly obtaining the desired effect of the present invention. The upper limit is not particularly limited, but is preferably 60 m ² /g or less, 50 m ² /g or less, or 40 m ² /g or less. The specific surface area can be obtained by adsorbing nitrogen on the sample surface using a specific surface area measuring device (Macsorb HM-1210 manufactured by MOUNTECH) according to the BET method, and calculating the specific surface area using the BET multipoint method.

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

Examples of commercially available surface treatment agents include "KBM403" (3-glycidyloxypropyltrimethoxysilane) manufactured by Shin-Etsu Chemical, "KBM803" (3-butylpropyltrimethoxysilane) manufactured by Shin-Etsu Chemical, "KBE903" (3-aminopropyltriethoxysilane) manufactured by Shin-Etsu Chemical, and "KBM573" (N-phenyl- 3-aminopropyltrimethoxysilane), Shin-Etsu Chemical Co., Ltd. "SZ-31" (hexamethyldisilazane), Shin-Etsu Chemical Co., Ltd. "KBM103" (phenyltrimethoxysilane), Shin-Etsu Chemical Co., Ltd. "KBM-4803" (long-chain epoxy-type silane coupling agent), Shin-Etsu Chemical Co., Ltd. "KBM-7103" (3,3,3-trifluoropropyltrimethoxysilane), etc.

The degree of surface treatment with a surface treatment agent is preferably limited to a specific range from the viewpoint of improving the dispersibility of the inorganic filler. Specifically, 0.2 to 5 parts by weight of the surface treatment agent is preferably used for surface treatment per 100 parts by weight of the inorganic filler, 0.2 to 3 parts by weight is preferably used for surface treatment, and 0.3 to 2 parts by weight is more preferably used for surface treatment.

The degree of surface treatment using a surface treatment agent can be evaluated by the amount of carbon per unit surface area of the inorganic filler. The amount of carbon per unit surface area of the inorganic filler is preferably 0.02 mg/ ^m2 or more, more preferably 0.1 mg/ ^m2 or more, and more preferably 0.2 mg/ ^m2 or more from the viewpoint of improving the dispersibility of the inorganic filler. On the other hand, from the viewpoint of suppressing the increase in the melt viscosity of the resin varnish and the melt viscosity of the flake form, it is preferably 1 mg/m2 or ^less , more preferably 0.8 mg/ ^m2 or less, and more preferably 0.5 mg/ ^m2 or less.

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

<(E) Thermoplastic resin> The resin composition may further contain (E) thermoplastic resin as an optional component in addition to the above components.

Examples of the thermoplastic resin as the component (E) include phenoxy resins, polyvinyl acetal resins, polyolefin resins, polybutadiene resins, polyimide resins, polyamide imide resins, polyether imide resins, polysulfide resins, polyethersulfide resins, polyphenylene ether resins, polycarbonate resins, polyetheretherketone resins, polyester resins, etc. Among them, phenoxy resins are preferred from the viewpoint of significantly achieving the desired effect of the present invention and obtaining an insulating layer with a small surface roughness and particularly excellent adhesion to the conductive layer. The thermoplastic resin may be used alone or in combination of two or more.

Examples of phenoxy resins include phenoxy resins having one or more skeletons selected from the group consisting of bisphenol A skeleton, bisphenol F skeleton, bisphenol S skeleton, bisphenol acetophenone skeleton, novolac skeleton, biphenyl skeleton, fluorene skeleton, dicyclopentadiene skeleton, norbornene skeleton, naphthalene skeleton, anthracene skeleton, adamantane skeleton, terpene skeleton, and trimethylcyclohexane skeleton. The terminal of the phenoxy resin may be any functional group such as a phenolic hydroxyl group or an epoxy group.

Specific examples of phenoxy resins include "1256" and "4250" manufactured by Mitsubishi Chemical Corporation (both are phenoxy resins containing bisphenol A skeleton); "YX8100" manufactured by Mitsubishi Chemical Corporation (phenoxy resin containing bisphenol S skeleton); "YX6954" manufactured by Mitsubishi Chemical Corporation (phenoxy resin containing bisphenol acetophenone skeleton); "FX280" and "FX293" manufactured by ; "YL7500BH30", "YX6954BH30", "YX7553", "YX7553BH30", "YL7769BH30", "YL6794", "YL7213", "YL7290" and "YL7482" manufactured by Mitsubishi Chemical Corporation.

Examples of polyvinyl acetal resins include polyvinyl formaldehyde resins and polyvinyl butyral resins, and polyvinyl butyral resins are preferred. Specific examples of polyvinyl acetal resins include "Denka Butyral 4000-2", "Denka Butyral 5000-A", "Denka Butyral 6000-C", and "Denka Butyral 6000-EP" manufactured by Denki Kagaku Kogyo Co., Ltd.; and S-LEC BH series, BX series (e.g., BX-5Z), KS series (e.g., KS-1), BL series, and BM series manufactured by Sekisui Chemical Kogyo Co., Ltd.

Specific examples of polyimide resins include "RIKACOAT SN20" and "RIKACOAT PN20" manufactured by Shin Nippon Rika Co., Ltd. Specific examples of polyimide resins include modified polyimides such as linear polyimides obtained by reacting bifunctional hydroxyl-terminated polybutadiene, a diisocyanate compound, and a tetrabasic acid anhydride (for example, polyimides described in Japanese Patent Application Laid-Open No. 2006-37083), polyimides containing a polysiloxane skeleton (polyimides described in Japanese Patent Application Laid-Open No. 2002-12667 and Japanese Patent Application Laid-Open No. 2000-319386, etc.).

Specific examples of polyamide imide resins include "VYLOMAX HR11NN" and "VYLOMAX HR16NN" manufactured by Toyo Boshin Co., Ltd. Specific examples of polyamide imide resins include modified polyamide imides such as "KS9100" and "KS9300" (polyamide imide containing a polysiloxane skeleton) manufactured by Hitachi Chemical Co., Ltd.

Specific examples of polyether sulphate resins include "PES5003P" manufactured by Sumitomo Chemical Co., Ltd.

Specific examples of polyphenylene ether resins include oligophenylene ether styrene resin "OPE-2St 1200" manufactured by Mitsubishi Gas Chemicals Co., Ltd.

Specific examples of the polyurethane resin include polyurethane "P1700" and "P3500" manufactured by Solvay Advanced Polymers.

(E) The weight average molecular weight (Mw) of the thermoplastic resin is preferably 8,000 or more, more preferably 10,000 or more, particularly preferably 20,000 or more, preferably 70,000 or less, more preferably 60,000 or less, particularly preferably 50,000 or less, from the viewpoint of remarkably obtaining the desired effect of the present invention.

(E) The content of the thermoplastic resin is preferably 0.1% by mass or more, more preferably 0.2% by mass or more, and even more preferably 0.3% by mass or more, and is preferably 5% by mass or less, more preferably 3% by mass or less, and even more preferably 1% by mass or less, when the non-volatile components in the resin composition are set to 100% by mass, from the viewpoint of significantly obtaining the desired effects of the present invention.

<(F) Hardener> The resin composition may further contain (F) hardener as an optional component in addition to the above-mentioned components. However, (B) active ester hardener is not included in (F) hardener. Examples of (F) hardener include phenol hardener, naphthol hardener, benzoxazine hardener, cyanate hardener, and carbodiimide hardener. Among them, from the viewpoint of improving insulation reliability, (F) hardener is preferably selected from any one or more of phenol hardener, naphthol hardener, cyanate hardener, and carbodiimide hardener, and more preferably contains phenol hardener. One hardener may be used alone, or two or more hardeners may be used in combination.

From the viewpoint of heat resistance and water resistance, the phenolic hardener and the naphthol hardener are preferably phenolic hardeners having a novolac structure or naphthol hardeners having a novolac structure. From the viewpoint of adhesion to the conductive layer, nitrogen-containing phenolic hardeners are preferred, and more preferably phenolic hardeners containing a triazine skeleton are preferred.

Specific examples of phenol-based hardeners and naphthol-based hardeners include "MEH-7700", "MEH-7810", and "MEH-7851" manufactured by Meiwa Chemicals, "NHN", "CBN", and "GPH" manufactured by Nippon Kayaku Co., Ltd., "SN170", "SN180", "SN190", "SN475", "SN485", "SN495", "SN-495V", "SN375", and "SN395" manufactured by Nippon Steel & Sumitomo Chemicals Corporation, and "TD-2090", "LA-7052", "LA-7054", "LA-1356", "LA-3018-50P", and "EXB-9500" manufactured by DIC Corporation.

Specific examples of benzoxazine-based hardeners include "HFB2006M" manufactured by Showa Polymer Co., Ltd., and "P-d" and "F-a" manufactured by Shikoku Chemical Industries, Ltd.

Examples of the cyanate curing agent include bisphenol A dicyanate, polyphenol cyanate, oligo(3-methylene-1,5-phenylene cyanate), 4,4'-methylenebis(2,6-dimethylphenyl cyanate), 4,4'-ethylenediphenyl dicyanate, hexafluorobisphenol A dicyanate, 2,2-bis(4-cyanate)phenylpropane, 1,1-bis(4-cyanatephenylmethane) , bifunctional cyanate resins such as bis(4-cyanate-3,5-dimethylphenyl)methane, 1,3-bis(4-cyanatephenyl-1-(methylethylidene))benzene, bis(4-cyanatephenyl)sulfide, and bis(4-cyanatephenyl)ether, polyfunctional cyanate resins derived from phenol novolac and cresol novolac, and prepolymers of these cyanate resins obtained by partially triazinizing them. Specific examples of cyanate-based curing agents include "PT30" and "PT60" (phenol novolac type multifunctional cyanate resins), "ULL-950S" (multifunctional cyanate resins), "BA230", and "BA230S75" (prepolymers of trimers of bisphenol A dicyanate that are partially or completely triazine-treated) manufactured by LONZA Corporation of Japan.

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

The value obtained by dividing the mass of the component (A) by the epoxy equivalent is set as a, and the value obtained by dividing the mass of the component (F) by the reactive group equivalent is set as f. The value "f" represents the equivalent number (eq.) of the reactive group contained in the component (F). In this case, f/a is preferably not less than 0.001, more preferably not less than 0.005, and even more preferably not less than 0.01, and is preferably not more than 3, more preferably not more than 2, and even more preferably not more than 1. Here, the reactive group of the curing agent is an active hydroxyl group, etc., which varies depending on the type of the curing agent. When the resin composition contains two or more (F) components, the above f is the total value of the value of the mass of each (F) component present in the resin composition divided by the reactive group equivalent for all (F) components. By setting the amount ratio of the epoxy resin to the hardener within this range, the heat resistance of the hardened product of the resin composition can be further improved.

(F) The content of the hardener is preferably 0.1% by mass or more, more preferably 0.2% by mass or more, and more preferably 0.3% by mass or more, based on the viewpoint of significantly obtaining the desired effect of the present invention, when the non-volatile components in the resin composition are set to 100% by mass. The upper limit is preferably 5% by mass or less, more preferably 3% by mass or less, and more preferably 1% by mass or less.

When the value obtained by dividing the mass of component (A) by the epoxy equivalent is a, the value obtained by dividing the mass of component (B) by the active ester equivalent is b, and the value obtained by dividing the mass of component (F) by the reactive group equivalent is f, (b+f)/a is preferably 1.1 or more, more preferably 1.3 or more, and more preferably 1.5 or more. The upper limit is preferably 5 or less, more preferably 3 or less, and more preferably 2 or less. By adjusting the amount ratio of component (A), component (B), and component (F) so that (b+f)/a is within this range, the dielectric tangent can be reduced and a cured product with excellent scum removal and adhesion can be obtained.

<(G) Hardening accelerator> In addition to the above-mentioned components, the resin composition may further contain (G) a hardening accelerator as an optional component.

Examples of the hardening accelerator include phosphorus-based hardening accelerators, amine-based hardening accelerators, imidazole-based hardening accelerators, guanidine-based hardening accelerators, and metal-based hardening accelerators. Among them, phosphorus-based hardening accelerators, amine-based hardening accelerators, imidazole-based hardening accelerators, and metal-based hardening accelerators are preferred, and amine-based hardening accelerators, imidazole-based hardening accelerators, and metal-based hardening accelerators are more preferred. The hardening accelerators may be used alone or in combination of two or more.

Examples of phosphorus-based hardening accelerators include triphenylphosphine, phosphonium borate compounds, tetraphenylphosphonium tetraphenylborate, n-butylphosphonium tetraphenylborate, tetrabutylphosphonium decanoate, (4-methylphenyl)triphenylphosphonium thiocyanate, tetraphenylphosphonium thiocyanate, butyltriphenylphosphonium thiocyanate, etc., preferably triphenylphosphine or tetrabutylphosphonium decanoate.

Examples of the amine-based hardening accelerator include trialkylamines such as triethylamine and tributylamine, 4-dimethylaminopyridine, benzyldimethylamine, 2,4,6-tris(dimethylaminomethyl)phenol, 1,8-diazabicyclo(5,4,0)-undecene, and the like, preferably 4-dimethylaminopyridine and 1,8-diazabicyclo(5,4,0)-undecene.

Examples of imidazole-based hardening accelerators include 2-methylimidazole, 2-undecylimidazole, 2-heptadecylimidazole, 1,2-dimethylimidazole, 2-ethyl-4-methylimidazole, 1,2-dimethylimidazole, 2-ethyl-4-methylimidazole, 2-phenylimidazole, 2-phenyl-4-methylimidazole, 1-benzyl-2-methylimidazole, 1-benzyl-2-phenylimidazole, 1-cyanoethyl-2- -methylimidazole, 1-cyanoethyl-2-undecylimidazole, 1-cyanoethyl-2-ethyl-4-methylimidazole, 1-cyanoethyl-2-phenylimidazole, 1-cyanoethyl-2-undecylimidazole trimellitate, 1-cyanoethyl-2-phenylimidazole trimellitate, 2,4-diamino-6-[2'-methylimidazolyl-(1')]-ethyl-s-triazine, 2,4-diamino-6 -[2'-Undecylimidazolyl-(1')]-ethyl-s-triazine, 2,4-diamino-6-[2'-ethyl-4'-methylimidazolyl-(1')]-ethyl-s-triazine, 2,4-diamino-6-[2'-methylimidazolyl-(1')]-ethyl-s-triazine isocyanuric acid adduct, 2-phenylimidazolyl isocyanuric acid adduct, 2-phenyl-4,5-dihydroxymethyl imidazole compounds such as imidazole, 2-phenyl-4-methyl-5-hydroxymethylimidazole, 2,3-dihydro-1H-pyrrolo[1,2-a]benzimidazole, 1-dodecyl-2-methyl-3-benzylimidazolium chloride, 2-methylimidazoline, 2-phenylimidazoline, and adducts of imidazole compounds with epoxy resins, preferably 2-ethyl-4-methylimidazole and 1-benzyl-2-phenylimidazole.

As the imidazole-based hardening accelerator, a commercially available product may be used, for example, "P200-H50" manufactured by Mitsubishi Chemical Corporation.

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

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

(G) The content of the hardening accelerator is preferably 0.01 mass % or more, more preferably 0.03 mass % or more, and further preferably 0.05 mass % or more, and is preferably 0.3 mass % or less, more preferably 0.2 mass % or less, and further preferably 0.1 mass % or less, based on 100 mass % of the non-volatile components in the resin composition.

＜(H) Polymerization initiator＞ In addition to the above components, the resin composition may further contain (H) a polymerization initiator as an optional component. The (H) polymerization initiator generally has a function of promoting the crosslinking of the (meth)acryloyl group of the (C) component. The (H) polymerization initiator may be used alone or in combination of two or more.

Examples of the (H) polymerization initiator include peroxides such as tert-butylcumyl peroxide, tert-butyl peroxyacetate, α,α'-di(tert-butylperoxy)diisopropylbenzene, tert-butylperoxylaurate, tert-butylperoxy-2-ethylhexanoate, tert-butylperoxyneodecanoate, and tert-butylperoxybenzoate.

Examples of commercially available products of the (H) polymerization initiator include "PERBUTYL C", "PERBUTYL P", "PERBUTYL L", "PERBUTYL O", "PERBUTYL ND", "PERBUTYL Z", "PERCUMYL P", "PERCUMYL D" and the like manufactured by NOF Corporation.

(H) The content of the polymerization initiator is preferably 0.01 mass % or more, more preferably 0.03 mass % or more, further preferably 0.05 mass % or more, and preferably 0.5 mass % or less, more preferably 0.3 mass % or less, further preferably 0.1 mass % or less, based on 100 mass % of the non-volatile components in the resin composition, and is preferably 0.5 mass % or less, more preferably 0.3 mass % or less, and further preferably 0.1 mass % or less.

<(I) Other additives> In addition to the above-mentioned components, the resin composition may further contain other additives as arbitrary components. Examples of such additives include organic fillers, thickeners, defoamers, leveling agents, adhesion-imparting agents, and other resin additives. These additives may be used alone or in combination of two or more.

<Physical properties and uses of resin composition> The resin composition was heat-cured at 130°C for 30 minutes and then heat-cured at 170°C for 30 minutes to produce a cured product that exhibited excellent slag removal properties. Therefore, when the cured product was used to form a through hole, an insulating layer was formed with a maximum slag length of less than 5 μm at the bottom of the through hole. The slag removal properties can be measured by the method described in the following embodiments.

The cured product obtained by heat curing the resin composition at 130°C for 30 minutes and then at 170°C for 30 minutes shows excellent adhesion (peeling strength) to the coated conductor layer. Therefore, the cured product obtains an insulating layer with excellent adhesion to the coated conductor layer. The adhesion strength to the coated conductor layer is preferably 0.2kgf/cm or more, more preferably 0.3kgf/cm or more, and even more preferably 0.4kgf/cm or more. On the other hand, the upper limit of the adhesion strength is not particularly limited, but can be set to 5kgf/cm or less. The evaluation of the adhesion strength to the coated conductor layer can be measured according to the method described in the embodiments described later.

The cured product obtained by heat curing the resin composition at 200°C for 90 minutes shows a property of low dielectric tangent. Therefore, the cured product obtains an insulating layer with low dielectric tangent. The dielectric tangent is preferably 0.005 or less, more preferably 0.004 or less, or 0.003 or less. On the other hand, the lower limit of the dielectric tangent is not particularly limited, but may be 0.0001 or more. The evaluation of the dielectric tangent can be measured according to the method described in the embodiment described later.

The resin composition of the present invention can reduce the dielectric tangent and obtain an insulating layer with excellent slag removal and adhesion. Therefore, the resin composition of the present invention can be preferably used as a resin composition for insulating purposes. Specifically, it can be preferably used as a resin composition for forming a conductive layer (including a redistribution layer) formed on an insulating layer (a resin composition for forming an insulating layer for forming a conductive layer).

Furthermore, it can be preferably used in a multilayer printed wiring board described later, as a resin composition for forming an insulating layer of a multilayer printed wiring board (resin composition for forming an insulating layer of a multilayer printed wiring board), or as a resin composition for forming an interlayer insulating layer of a printed wiring board (resin composition for forming an interlayer insulating layer of a printed wiring board).

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

Furthermore, the resin composition of the present invention can obtain an insulating layer with good component embedding properties, so it can also be preferably applied to the case where the printed wiring board is a circuit board with built-in components.

[Resin sheet] The resin sheet of the present invention comprises a support and a resin composition layer formed of the resin composition of the present invention and disposed on the support.

The thickness of the resin composition layer is preferably 50 μm or less, more preferably 40 μm or less, and even more preferably 30 μm or less, based on the viewpoint of thinning the printed wiring board and providing a cured product with excellent insulation even if the cured product of the resin composition is a thin film. The lower limit of the thickness of the resin composition layer is not particularly limited, but can generally be set to 5 μm or more, 10 μm or more, etc.

Examples of the support include films made of plastic materials, metal foils, and release paper, and films made of plastic materials and metal foils are preferred.

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

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

The support body may also be subjected to a matte treatment, a corona treatment, or an antistatic treatment on the surface that is bonded to the resin composition layer.

Furthermore, as a support, a support with a release layer having a release layer on the surface bonded to the resin composition layer can also be used. Examples of release agents used in the release layer of the support with a release layer include at least one release agent selected from the group consisting of alkyd resins, polyolefin resins, urethane resins, and silicone resins. The support body with a release layer may also use commercially available products, such as "SK-1", "AL-5", "AL-7" manufactured by LINTEC, "LUMIRROR T60" manufactured by Toray Industries, "PUREX" manufactured by Teijin, "UNIPEEL" manufactured by UNITIKA, etc., which are PET films having a release layer with an alkyd resin-based release agent as the main component.

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

In one embodiment, the resin sheet may further include other layers as needed. Examples of such other layers include a protective film for the support provided on the surface of the resin composition layer that is not bonded to the support (i.e., the surface on the opposite side of the support). The thickness of the protective film is not particularly limited, but may be, for example, 1 μm to 40 μm. By laminating the protective film, it is possible to suppress the adhesion or scratching of dirt and the like on the surface of the resin composition layer.

The resin sheet can be manufactured by, for example, preparing a resin varnish in which a resin composition is dissolved in an organic solvent, applying the resin varnish on a support using a die-mouth coater, and then drying to form a resin composition layer.

Examples of organic solvents include ketones such as acetone, methyl ethyl ketone (MEK), and cyclohexanone; acetates such as ethyl acetate, butyl acetate, cellulose acetate, propylene glycol monomethyl ether acetate, and carbitol acetate; carbitols such as cellulose and butyl carbitol; aromatic hydrocarbons such as toluene and xylene; amide solvents such as dimethylformamide, dimethylacetamide (DMAc), and N-methylpyrrolidone. The organic solvents may be used alone or in combination of two or more.

Drying can be carried out by known methods such as heating and hot air blowing. The drying conditions are not particularly limited, but the resin composition layer is dried until the organic solvent content is 10% by mass or less, preferably 5% by mass or less. Although it varies depending on the boiling point of the organic solvent in the resin varnish, for example, when a resin varnish containing 30% to 60% by mass of an organic solvent is used, the resin composition layer can be formed by drying at 50°C to 150°C for 3 minutes to 10 minutes.

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

[Printed wiring board] The printed wiring board of the present invention includes an insulating layer formed by a cured product of the resin composition of the present invention.

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

The "inner layer substrate" used in step (I) is a component that becomes the substrate of the printed wiring board, and examples include glass epoxy substrates, metal substrates, polyester substrates, polyimide substrates, BT resin substrates, thermosetting polyphenylene ether substrates, etc. The substrate may also have a conductive layer on one or both sides, and the conductive layer may also be processed by graphics. The inner layer substrate with a conductive layer (circuit) formed on one or both sides of the substrate is sometimes called an "inner layer circuit substrate". When manufacturing a printed wiring board, all intermediate products that further form an insulating layer and/or a conductive layer are included in the "inner layer substrate" referred to in the present invention. When the printed wiring board is a circuit board with built-in components, an inner layer substrate with built-in components can be used.

The inner substrate and the resin sheet can be laminated by, for example, heating and pressing the resin sheet onto the inner substrate from the support body side. Examples of the member for heating and pressing the resin sheet onto the inner substrate (hereinafter also referred to as the "heating and pressing member") include a heated metal plate (SUS mirror plate, etc.) or a metal roller (SUS roller). In addition, it is preferred that the heating and pressing member is not directly pressed onto the resin sheet, but is pressed via an elastic material such as heat-resistant rubber in a manner that allows the resin sheet to fully follow the surface irregularities of the inner substrate.

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

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

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

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

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

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

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

When manufacturing a printed wiring board, the steps (III) of drilling holes in the insulating layer, (IV) of roughening the insulating layer, and (V) of forming a conductive layer may be further performed. The steps (III) to (V) may be performed according to various methods known to those skilled in the art for manufacturing printed wiring boards. Furthermore, when the support is removed after step (II), the removal of the support may be performed between step (II) and step (III), between step (III) and step (IV), or between step (IV) and step (V). Furthermore, as required, the formation of the insulating layer and the conductive layer in steps (II) to (V) may be repeated to form a multi-layer wiring board.

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

Step (IV) is a step of roughening the insulating layer. Usually, in step (IV), the slurry is also removed. The order and conditions of the roughening treatment are not particularly limited, and the known order and conditions commonly used when forming the insulating layer of the printed wiring board can be adopted. For example, the insulating layer is roughened by swelling treatment with a swelling liquid, roughening treatment with an oxidizing agent, and neutralization treatment with a neutralizing liquid in sequence. The swelling liquid used for the roughening treatment is not particularly limited, but examples include alkaline solutions, surfactant solutions, etc., preferably alkaline solutions, and more preferably sodium hydroxide solutions and potassium hydroxide solutions as the alkaline solution. Examples of commercially available swelling liquids include "Swelling Dip Securiganth P" and "Swelling Dip Securiganth SBU" manufactured by ATOTECH Co., Ltd. of Japan. The swelling treatment using the swelling liquid is not particularly limited, but for example, the insulating layer may be immersed in a swelling liquid at 30°C to 90°C for 1 minute to 20 minutes. From the viewpoint of suppressing the swelling of the resin of the insulating layer to an appropriate degree, it is preferred that the insulating layer be immersed in a swelling liquid at 40°C to 80°C for 5 minutes to 15 minutes. The oxidizing agent used for the roughening treatment is not particularly limited, but an example is an alkaline permanganic acid solution in which potassium permanganate or sodium permanganate is dissolved in an aqueous sodium hydroxide solution. The roughening treatment using an oxidizing agent such as an alkaline permanganic acid solution is preferably performed by immersing the insulating layer in the oxidizing agent solution heated to 60°C to 100°C for 10 minutes to 30 minutes. Moreover, the concentration of permanganate in the alkaline permanganic acid solution is preferably 5% by mass to 10% by mass. Examples of commercially available oxidizing agent solutions include alkaline permanganic acid solutions such as "Concentrate Compact CP" and "Doesing Solution Securiganth P" manufactured by ATOTECH Corporation of Japan. The neutralizing solution used for the roughening treatment is preferably an acidic aqueous solution, and a commercially available product is, for example, "Reduction Solution Securiganth P" manufactured by ATOTECH Co., Ltd. of Japan. The treatment using the neutralizing solution is performed by immersing the treated surface after the roughening treatment with the oxidant in the neutralizing solution at 30°C to 80°C for 5 minutes to 30 minutes. From the perspective of workability, it is better to immerse the object roughening treatment with the oxidant in the neutralizing solution at 40°C to 70°C for 5 minutes to 20 minutes.

In one embodiment, the arithmetic mean roughness (Ra) of the insulating layer surface after the roughening treatment is preferably 400 nm or less, more preferably 350 nm or less, and more preferably 300 nm or less. There is no particular limitation on the lower limit, but it is preferably 0.5 nm or more, and more preferably 1 nm or more. And the average square root roughness (Rq) of the insulating layer surface after the roughening treatment is preferably 400 nm or less, more preferably 350 nm or less, and more preferably 300 nm or less. There is no particular limitation on the lower limit, but it is preferably 0.5 nm or more, and more preferably 1 nm or more. The arithmetic mean roughness (Ra) and average square root roughness (Rq) of the insulating layer surface can be measured using a non-contact surface roughness meter.

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

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

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

In one embodiment, the conductive layer can also be formed by plating. For example, by plating on the surface of the insulating layer using conventional techniques such as semi-additive method and full-additive method, a conductive layer having a desired wiring pattern can be formed. From the perspective of manufacturing simplicity, it is preferably formed by semi-additive method. The following shows an example of forming a conductive layer using semi-additive method.

First, a seed layer is formed on the surface of the insulating layer by electroless plating. Next, a mask pattern is formed on the formed seed layer to expose a portion of the seed layer corresponding to the desired wiring pattern. After a metal layer is formed on the exposed seed layer by electrolytic plating, the mask pattern is removed. Subsequently, the unnecessary seed layer is removed by etching, etc., and a conductor layer with a desired wiring pattern can be formed.

[Semiconductor device] The semiconductor device of the present invention includes the printed wiring board of the present invention. The semiconductor device of the present invention can be manufactured using the printed wiring board of the present invention.

Examples of semiconductor devices include various semiconductor devices used in electrical products (such as computers, mobile phones, digital cameras, and televisions) and vehicles (such as motorcycles, cars, trains, ships, and airplanes).

The semiconductor device of the present invention can be manufactured by mounting a component (semiconductor chip) on the conductive part of a printed wiring board. The so-called "conductive part" is "the part of the printed wiring board that transmits electrical signals", and the location can be the surface or the embedded part. Moreover, the semiconductor chip is not particularly limited as long as it is an electrical circuit element made of semiconductor.

The semiconductor chip mounting method when manufacturing semiconductor devices is not particularly limited as long as it can effectively exert the function of the semiconductor chip. Specific examples include wire bonding mounting method, flip chip mounting method, mounting method using bumpless build-up layer (BBUL), mounting method using anisotropic conductive film (ACF), mounting method using non-conductive film (NCF), etc. Here, the so-called "mounting method using bumpless build-up layer (BBUL)" is "a mounting method of directly embedding a semiconductor chip in a recess of a printed wiring board and connecting the semiconductor chip to the wiring on the printed wiring board." [Example]

The present invention is specifically described below by way of examples. However, the present invention is not limited to the following examples. In the following description, "parts" and "%" indicating quantities mean "parts by mass" and "% by mass" respectively unless otherwise specified. The operations described below are performed at room temperature and pressure unless otherwise specified.

[Example 1] 10 parts of bisphenol epoxy resin ("ZX1059" manufactured by Nippon Steel & Sumitomo Chemical Co., Ltd., a 1:1 mixture of bisphenol A and bisphenol F, epoxy equivalent 169 g/eq.) and 50 parts of naphthol epoxy resin ("ESN475V" manufactured by Nippon Steel & Sumitomo Chemical Co., Ltd., epoxy equivalent about 330 g/eq.) were dissolved in 40 parts of naphtha solvent while stirring. The mixture was cooled to room temperature to prepare a dissolving composition of epoxy resin.

In the epoxy resin solution, 5 parts of phenoxy resin ("YX7553BH30" manufactured by Mitsubishi Chemical, a 1:1 solution of MEK and cyclohexanone with a non-volatile content of 30% by mass), 5 parts of phenolic hardener having a triazine skeleton and a novolac structure ("LA-3018-50P" manufactured by DIC, an active group equivalent of about 151 g/eq., a 2-methoxypropanol solution with a non-volatile content of 50%), 110 parts of active ester hardener ("HPC-8000-65T" manufactured by DIC, an active group equivalent of about 223 g/eq., a toluene solution with a non-volatile content of 65% by mass), and (meth)acrylate (A-DOG, manufactured by Shin-Nakamura Chemical Co., Ltd.) were mixed. 15 parts, a curing accelerator (1-benzyl-2-phenylimidazole (1B2PZ), a MEK solution with a non-volatile content of 10% by mass), 5 parts, PERBUTYL P as a polymerization initiator (manufactured by NOF Corporation, a MEK solution with a non-volatile content of 20%), 2 parts, spherical silica (average particle size 0.5μm, specific surface area ^5.9m2 /g, "SO-C2" manufactured by ADMATECHS) surface-treated with an amine-based alkoxysilane compound ("KBM573" manufactured by Shin-Etsu Chemical Co., Ltd.), 10 parts of cyclohexanone, and 10 parts of MEK were uniformly dispersed in a high-speed rotary mixer to prepare a resin varnish.

A-DOG has the following structure.

A polyethylene terephthalate (PET) film ("AL5" manufactured by LINTEC, thickness 38 μm) with a release layer was prepared as a support. The resin varnish was uniformly applied on the release layer of the support so that the thickness of the resin composition layer after drying would be 25 μm. The resin varnish was then dried at 80°C to 100°C (average 90°C) for 6 minutes to obtain a resin sheet including the support and the resin composition layer.

[Example 2] In Example 1, 110 parts of active ester hardener ("HPC-8000-65T" manufactured by DIC Corporation, active group equivalent of about 223 g/eq., toluene solution with non-volatile matter of 65% by mass) were replaced with 110 parts of active ester hardener ("HPC-8000L-65TM" manufactured by DIC Corporation, active group equivalent of 220 g/eq., toluene-MEK mixed solution with non-volatile matter of 65%). Except for the above matters, resin varnish and resin sheet were produced in the same manner as in Example 1.

[Example 3] In Example 1, 110 parts of active ester hardener ("HPC-8000-65T" manufactured by DIC Corporation, active group equivalent of about 223 g/eq., toluene solution with non-volatile matter of 65% by mass) were replaced with 120 parts of active ester hardener ("EXB-8150-60T" manufactured by DIC Corporation, active group equivalent of 230 g/eq., toluene solution with non-volatile matter of 60%). Except for the above matters, resin varnish and resin sheet were manufactured in the same manner as in Example 1.

[Example 4] In Example 3, 15 parts of acrylate (A-DOG, manufactured by Shin-Nakamura Chemical Co., Ltd.) was replaced with 15 parts of acrylate (DCP-A, manufactured by Kyoeisha Chemical Co., Ltd.). Except for the above matters, the resin varnish and resin sheet were prepared in the same manner as in Example 3.

DCP-A has the structure shown below.

[Example 5] In Example 4, the amount of active ester hardener (DIC "EXB-8150-60T", active group equivalent 230g/eq., 60% non-volatile matter toluene solution) was changed from 120 parts to 140 parts, and the amount of spherical silica (average particle size 0.5μm, ADMATECHS "SO-C2") surface-treated with an amine alkoxysilane compound (Shin-Etsu Chemical "KBM573") was changed from 510 parts to 520 parts. Except for the above matters, the resin varnish and resin sheet were produced in the same manner as in Example 4.

[Comparative Example 1] In Example 3, 15 parts of acrylate (A-DOG, manufactured by Shin-Nakamura Chemical Co., Ltd.) were not used, and the amount of spherical silica (average particle size 0.5 μm, "SO-C2" manufactured by ADMATECHS Co., Ltd.) surface-treated with an amine-based alkoxysilane compound ("KBM573" manufactured by Shin-Etsu Chemical Co., Ltd.) was changed from 510 parts to 480 parts. Except for the above matters, the resin varnish and resin sheet were manufactured in the same manner as in Example 3.

[Comparative Example 2] In Example 3, the amount of active ester hardener (DIC "EXB-8150-60T", active group equivalent 230g/eq., 60% non-volatile matter toluene solution) was changed from 120 parts to 80 parts, and the amount of spherical silica (average particle size 0.5μm, ADMATECHS "SO-C2") surface-treated with an amine alkoxysilane compound (Shin-Etsu Chemical "KBM573") was changed from 510 parts to 450 parts. Except for the above matters, the resin varnish and resin sheet were produced in the same manner as in Example 3.

[Evaluation of slag removal and plating peel strength] <Evaluation of substrate A production> (1) Base treatment of interior substrate: A glass cloth-based epoxy resin double-sided copper laminate with copper foil on the surface (copper foil thickness 18μm, substrate thickness 0.8mm, "R1515A" manufactured by PANASONIC) was prepared as the inner substrate. The copper foil on the surface of the inner substrate was etched with a micro-etching agent ("ZC8101" manufactured by MERCK) with a copper etching amount of 1μm to perform a roughening treatment. Then, it was dried at 190°C for 30 minutes.

(2) Lamination and curing of resin sheets The resin sheets obtained in the above-mentioned embodiments and comparative examples were laminated on both sides of the inner substrate using a batch vacuum pressure laminator (2-stage build-up laminator "CVP700" manufactured by NIKKO MATERIALS) in such a way that the resin composition layer was bonded to the inner substrate. The lamination was performed by reducing the pressure for 30 seconds to a pressure of 13 hPa or less, and then pressing at a temperature of 100°C and a pressure of 0.74 MPa for 30 seconds.

Next, the laminated resin sheet was smoothed by hot pressing at 100°C and 0.5 MPa for 60 seconds under atmospheric pressure. It was then placed in an oven at 130°C for 30 minutes, and then moved to an oven at 170°C for 30 minutes.

(3) Formation of through holes The insulating layer was processed using a _CO2 laser processing machine (LK-2K212/2C) manufactured by VIA MECHANICS at a frequency of 2000 Hz, a pulse width of 3 μs, an output of 0.95 W, and a shot number of 3 to form through holes with a top diameter (diameter) of 50 μm on the insulating layer surface and a bottom diameter of 40 μm. The PET film was then peeled off.

(4) Roughening treatment: The inner layer substrate was immersed in the swelling liquid Swelling Dip Securiganth P of Japan ATOTECH Co., Ltd. at 60°C for 10 minutes. Then, it was immersed in the roughening liquid Concentrate Compact P (KMnO ₄ : 60g/L, NaOH: 40g/L aqueous solution) of Japan ATOTECH Co., Ltd. at 80°C for 20 minutes. Finally, it was immersed in the neutralizing liquid Reduction Solution Securiganth P of Japan ATOTECH Co., Ltd. at 40°C for 5 minutes. The obtained substrate was used as the evaluation substrate A.

<Evaluation of residue at the bottom of through-hole (evaluation of slag removal performance)> The bottom of the through-hole of substrate A was observed and evaluated using a scanning electron microscope (SEM). The maximum slag length from the wall surface at the bottom of the through-hole was measured from the obtained image and evaluated according to the following criteria. ○: The maximum slag length is less than 5μm. ×: The maximum slag length is more than 5μm.

<Determination of plating peel strength> The evaluation substrate A was immersed in an electroless plating solution containing PdCl ₂ at 40°C for 5 minutes, and then immersed in an electroless copper plating solution at 25°C for 20 minutes. After heating at 150°C for 30 minutes for annealing, an etching resist was formed. After patterning was formed by etching, copper sulfate electrolytic plating was performed to form a 30μm thick conductor layer. Next, annealing was performed at 200°C for 60 minutes, and the resulting substrate was used as the evaluation substrate B.

A portion of 10 mm wide and 150 mm long was cut into the conductive layer of the evaluation substrate B, and one end was peeled off and pinched with a pinching tool (manufactured by DSE, Autocom tester AC-50C-SL). The load (kgf/cm) when 100 mm was torn off in the vertical direction at a speed of 50 mm/min at room temperature (25°C) was measured.

[Determination of dielectric tangent] The resin sheets obtained in the above-mentioned examples and comparative examples were heat-cured at 190°C for 90 minutes, and the PET film was peeled off to obtain a thin sheet of cured product. The cured product was cut into test pieces with a width of 2 mm and a length of 80 mm. The dielectric tangent (tanδ) was measured using the cavity oscillator propagation method dielectric constant measuring device CP521 manufactured by Kanto Applied Electronics Development Co., Ltd. and the network analyzer E8362B manufactured by Agilent Technologies Co., Ltd. using the cavity resonance method at a measuring frequency of 5.8 GHz. The measurement was performed on two test pieces and the average value was calculated.

In the table, "a" represents the value obtained by dividing the mass of component (A) by the epoxy equivalent, "b" represents the value obtained by dividing the mass of component (B) by the active ester equivalent, and "f" represents the value obtained by dividing the mass of component (F) by the reactive group equivalent. "Content of component (C)" represents the content of component (C) when the resin component in the resin composition is assumed to be 100% by mass, and "Content of component (D)" represents the content of component (D) when the non-volatile component in the resin composition is assumed to be 100% by mass.

In Examples 1 to 5, even when the components (E) to (H) were not contained, the results were confirmed to be the same as those of the above examples, although the degree was different.

Claims (14)

A resin composition comprising (A) an epoxy resin, (B) an active ester hardener, (C) a (meth)acrylate, (D) an inorganic filler, and (F) a hardener; however, the active ester hardener (B) is not included in the hardener (F); the content of the component (D) is 70% by mass or more when the non-volatile components in the resin composition are taken as 100% by mass; when the value obtained by dividing the mass of the component (A) by the epoxy equivalent is a, and the value obtained by dividing the mass of the component (B) by the active ester equivalent is b, b/a is 1.3 or more and 5 or less; when the value obtained by dividing the mass of the component (F) by the reactive group equivalent is f, f/a is 0.001 or more and 3 or less. The resin composition of claim 1, wherein component (C) has two or more (meth)acryloyl groups per molecule. The resin composition of claim 1, wherein component (C) has a ring structure. The resin composition of claim 1, wherein the component (C) has a structure represented by the following formula (1):

(In formula (1), ^R1 and ^R4 each independently represent an acryl group or a methacryl group, ^R2 and ^R3 each independently represent an alkylene group, an alkenylene group, an arylene group, a heteroarylene group, -C(=O)O-, -O-, -NHC(=O)-, -NC(=O)N-, -NHC(=O)O-, -C(=O)-, -S-, -SO- or -NH-, and ring A represents a divalent cyclic group selected from the following (i) to (xi))

The resin composition of claim 1, wherein component (A) comprises a liquid epoxy resin and a solid epoxy resin. In the resin composition of claim 1, the content of component (D) is 75% by mass or more when the non-volatile components in the resin composition are set to 100% by mass. In the resin composition of claim 1, the content of component (C) is 1% by mass or more and 20% by mass or less when the resin component in the resin composition is set to 100% by mass. The resin composition of claim 1 is used for insulation purposes. The resin composition of claim 1 is used to form an insulating layer. The resin composition of claim 1 is used to form an insulating layer of a conductive layer. The resin composition of claim 1 is used for sealing semiconductor chips. A resin sheet comprising a support body and a resin composition layer disposed on the support body and containing a resin composition as described in any one of claims 1 to 11. A printed wiring board comprising an insulating layer formed by a cured product of a resin composition as recited in any one of claims 1 to 11. A semiconductor device comprising a printed wiring board as claimed in claim 13.