TWI845525B - Resin composition - Google Patents

Abstract

[Purpose] The present invention provides a resin composition capable of producing a cured product having excellent storage stability of a resin coating and a low loss factor; a resin sheet containing the resin composition; a printed wiring board having an insulating layer formed using the resin composition; and a semiconductor device. [Solution] A resin composition comprising: (A) an epoxy resin, (B) a hardener, (C) a styrene-based elastomer, and (D) a resin having a free radical polymerizable unsaturated group; the content of styrene units in the component (C) is 61% by mass or more when the component (C) is 100% by mass.

Description

Resin composition

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

At present, the manufacturing technology of printed wiring boards is known to be a manufacturing method in which an insulating layer and a conductive layer are stacked in an alternating manner on an inner circuit substrate. However, in recent years, the demand for insulating layers that can reduce electrical signal loss at high frequencies has increased, so an insulating layer with a low loss factor is urgently needed.

The resin composition that can form these insulating layers can be exemplified as follows: Patent document 1 describes a resin composition comprising: (A) a thermosetting resin having a molecular weight of 800 to 1500 and having a styrene group at the end, (B) a liquid epoxy resin, (C) a styrene-based thermoplastic elastomer, (D) a filler, and (E) a hardener, wherein the component (D) is contained in an amount of 30 to 70 parts by mass relative to 100 parts by mass of the resin composition. [Prior art document] [Patent document]

[Patent Document 1] Japanese Patent Application No. 2016-147945

[The problem the invention is trying to solve]

The inventors of the present invention have studied a resin composition containing a radical polymerizable compound that can make the entire resin composition low-polarizable in order to obtain an insulating layer with a low loss coefficient. As a result, they have found that the resin composition containing the radical polymerizable compound has a new problem of deterioration in storage stability in a resin coating formed by dissolving the resin composition in an organic solvent.

The purpose of the present invention is to provide a resin composition that can produce a cured product having excellent storage stability of a resin coating and a low loss factor; a resin sheet containing the resin composition; and a printed wiring board and a semiconductor device having an insulating layer formed using the resin composition. [Method for solving the problem]

The inventors of the present invention have conducted in-depth research to solve the above-mentioned problems and have found that a resin composition containing (D) a resin having a free radical polymerizable unsaturated group, (A) an epoxy resin, (B) a hardener, and (C) a styrene-based elastomer having a styrene unit content within a specific range can solve the above-mentioned problems, thereby completing the present invention. That is, the present invention includes the following contents.

[1] A resin composition comprising: (A) an epoxy resin, (B) a hardener, (C) a styrene-based elastomer, and (D) a resin having a free radical polymerizable unsaturated group; and the content of styrene units in the component (C) is 61% by mass or more, when the component (C) is 100% by mass. [2] The resin composition as described in [1], wherein the content of the component (C) is 0.5% by mass or more and 18% by mass or less, when the resin component in the resin composition is 100% by mass. [3] The resin composition as described in [1] or [2], wherein the component (D) contains at least one selected from vinylphenyl, acryl, and methacryl. [4] The resin composition as described in any one of [1] to [3], wherein the number average molecular weight of component (D) is 3000 or less. [5] The resin composition as described in any one of [1] to [4], further comprising (E) an inorganic filler. [6] The resin composition as described in [5], wherein the content of component (E) is 50% by mass or more when the non-volatile components in the resin composition are 100% by mass. [7] The resin composition as described in any one of [1] to [6], which is used to form an insulating layer. [8] The resin composition as described in any one of [1] to [7], which is used to form an insulating layer for the purpose of forming a conductive layer. [9] The resin composition described in any one of [1] to [8] is used as an insulating layer for forming a conductive layer by sputtering or metal foil. [10] The resin composition described in any one of [1] to [9] is used as an insulating layer for forming a via hole having a top diameter of 45 μm or less. [11] The resin composition described in any one of [1] to [10] is used as an insulating layer having a thickness of 20 μm or less. [12] A resin sheet comprising: a support body, and a resin composition layer disposed on the support body and containing the resin composition described in any one of [1] to [11]. [13] A printed wiring board comprising: an insulating layer formed by a cured product of the resin composition described in any one of [1] to [11]. [14] A semiconductor device comprising the printed wiring board described in [13]. [Effect of the Invention]

According to the present invention, a resin composition capable of producing a cured product having excellent storage stability of a resin coating and a low loss factor can be provided; a resin sheet containing the resin composition; and a printed wiring board and a semiconductor device having an insulating layer formed using the resin composition.

[Form of implementing the invention]

The following will list 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 any changes and implementations are possible as long as they do not exceed the scope of the patent application of the present invention and its equivalent scope.

[Resin composition] The resin composition of the present invention contains: (A) epoxy resin, (B) hardener, (C) styrene elastomer, and (D) resin having free radical polymerizable unsaturated groups; the content of styrene units in component (C) is 61% by mass or more when component (C) is 100% by mass. When these resin compositions are used, a hardened material having excellent storage stability of resin coating and low loss coefficient can be produced. In addition, when these resin compositions are used, the peel strength between the conductive layer and the conductive layer can usually be improved.

The resin composition may contain any other component in the combination of components (A) to (D). The optional component may include: (E) inorganic filler, (F) styrene elastomer other than components (C), (G) hardening accelerator, (H) polymerization initiator, and (I) other additives. The following is a detailed description of each component contained in the resin composition.

<(A) Epoxy resin> (A) Epoxy resins include: bimethylol epoxy resin, bisphenol A epoxy resin, bisphenol F epoxy resin, bisphenol S epoxy resin, bisphenol AF epoxy resin, dicyclopentadiene epoxy resin, trisphenol epoxy resin, naphthol-phenol novolac epoxy resin, phenol-phenol novolac epoxy resin, tert-butyl-catechol epoxy resin, naphthalene epoxy resin, naphthol epoxy resin, anthracene epoxy resin, Epoxy resins, glycidylamine type epoxy resins, glycidyl ester type epoxy resins, cresol-novolac type epoxy resins, biphenyl type epoxy resins, linear aliphatic epoxy resins, epoxy resins having a butadiene structure, alicyclic epoxy resins, heterocyclic epoxy resins, spirocyclic epoxy resins, cyclohexane type epoxy resins, cyclohexanedimethanol type epoxy resins, naphthyl ether type epoxy resins, trihydroxymethyl type epoxy resins, tetraphenylethane type epoxy resins, and the like. The epoxy resin may be used alone or in combination of two or more.

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

The epoxy resin includes an epoxy resin that is liquid at 20°C (hereinafter, also referred to as "liquid epoxy resin") and an epoxy resin that is solid at 20°C (hereinafter, also referred to as "solid epoxy resin"). In the resin composition, (A) epoxy resin may contain only a liquid epoxy resin, only a solid epoxy resin, or a combination of a liquid epoxy resin and a solid epoxy resin.

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.

Solid epoxy resins include: dimethylol type epoxy resins, naphthalene type epoxy resins, naphthalene type tetrafunctional epoxy resins, cresol-phenolic varnish 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, tetraphenylethane type epoxy resins are preferred, and naphthalene type epoxy resins are more preferred.

Specific examples of solid epoxy resins include: "HP4032H" manufactured by DIC Corporation (naphthalene-based epoxy resin); "HP-4700" and "HP-4710" manufactured by DIC Corporation (naphthalene-based tetrafunctional epoxy resin); "N-690" manufactured by DIC Corporation (cresol-phenolic varnish-based epoxy resin); "N-695" manufactured by DIC Corporation (cresol-phenolic varnish-based epoxy resin); "HP-7200", "HP-7200H ... "EXA-7311", "EXA-7311-G3", "EXA-7311-G4", "EXA-7311-G4S", "HP6000" (epoxy naphthyl ether type epoxy resin) manufactured by DIC Corporation; "EPPN-502H" (trisphenol type epoxy resin) manufactured by Nippon Kayaku Co., Ltd.; "NC7000L" (naphthol-phenol novolac type epoxy resin) manufactured by Nippon Kayaku Co., Ltd.; "NC3000H" (epoxy naphthyl phenol novolac type epoxy resin) manufactured by Nippon Kayaku Co., Ltd. ", "NC3000", "NC3000L", "NC3100" (biphenyl type epoxy resin); "ESN475V" manufactured by Nippon Steel & Sumitomo Chemical Co., Ltd. (naphthol type epoxy resin); "ESN485" manufactured by Nippon Steel & Sumitomo Chemical Co., Ltd. (naphthol-phenolic varnish 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 "YL7760" (bisphenol AF type epoxy resin) manufactured by Mitsubishi Chemical; "YL7800" (fluorene type epoxy resin) manufactured by Mitsubishi Chemical; "jER1010" (solid bisphenol A type epoxy resin) manufactured by Mitsubishi Chemical; "jER1031S" (tetraphenylethane type epoxy resin) manufactured by Mitsubishi Chemical, etc. These may be used alone or in combination of two or more.

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

Liquid epoxy resins, for example, bisphenol A type epoxy resins, bisphenol F type epoxy resins, bisphenol AF type epoxy resins, naphthalene type epoxy resins, glycidyl ester type epoxy resins, glycidyl amine type epoxy resins, phenol-novolac type epoxy resins, alicyclic epoxy resins having an ester skeleton, cyclohexane type epoxy resins, cyclohexanedimethanol type epoxy resins, glycidyl amine type epoxy resins, and epoxy resins having a butadiene structure are preferred, with bisphenol A type epoxy resins and bisphenol F type epoxy resins being more preferred.

Examples of liquid epoxy resins include HP4032, HP4032D, and HP4032SS (naphthalene epoxy resins) manufactured by DIC Corporation; 828US, jER828EL, 825, and Epikote manufactured by Mitsubishi Chemical Corporation; "828EL" (bisphenol A type epoxy resin); "jER807" and "1750" (bisphenol F type epoxy resin) manufactured by Mitsubishi Chemical Corporation; "jER152" (phenol-novolac type epoxy resin) manufactured by Mitsubishi Chemical Corporation; "630" and "630LSD" (glycidylamine type epoxy resin) manufactured by Mitsubishi Chemical Corporation; "ZX1059" (a mixture of bisphenol A type epoxy resin and bisphenol F type epoxy resin) manufactured by Nippon Steel & Sumitomo Chemical Corporation; "EX-721" (glycidyl ester type epoxy resin) manufactured by Nagase Chemical Technology Co., Ltd.; "Celloxide "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 Chemicals (liquid 1,4-glycidylcyclohexane type epoxy resins), etc. These may be used alone or in combination of two or more.

(A) When a liquid epoxy resin of an epoxy resin is used in combination with a solid epoxy resin, the ratio of these amounts (liquid epoxy resin: 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, based on the mass ratio. When the amount ratio of the liquid epoxy resin to the solid epoxy resin is within this range, the expected effect of the present invention can be significantly obtained. In addition, when it is usually used in the form of a resin sheet, appropriate adhesion can also be obtained. In addition, when it is usually used in the form of a resin sheet, sufficient flexibility can be obtained and the handling property can be improved. In addition, a hardened material with sufficient breaking strength can also 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., particularly preferably 80 g/eq. to 2000 g/eq., and most preferably 110 g/eq. to 1000 g/eq. Within this range, the resin can provide the composite layer and the cured product with sufficient crosslinking density, thereby producing an insulating layer with a smaller surface roughness. The epoxy equivalent is the mass of the epoxy resin containing 1 equivalent of epoxy group. The epoxy equivalent can be measured in accordance with JIS K7236.

(A) The weight average molecular weight (Mw) of the epoxy resin is preferably 100 to 5000, more preferably 250 to 3000, and particularly preferably 400 to 1500, in order to significantly achieve the desired effect of the present invention. The weight average molecular weight of the resin is the value converted to polystyrene measured by gel permeation chromatography (GPC).

(A) The content of epoxy resin is preferably 1% by mass or more, more preferably 2% by mass or more, and particularly preferably 3% by mass or more, from the viewpoint of obtaining an insulating layer having 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 15% by mass or less, more preferably 10% by mass or less, and particularly preferably 5% by mass or less, from the viewpoint of significantly obtaining the expected effect of the present invention. In addition, in the present invention, the content of each component in the resin composition refers to the value relative to the non-volatile components in the resin composition being set to 100% by mass, unless otherwise clearly stated.

＜(B) Hardener＞ In the resin composition, the (B) component contains a hardener. The (B) hardener usually has the function of reacting with the (A) epoxy resin to harden the resin composition.

(B) Hardeners, such as active ester hardeners, phenol hardeners, naphthol hardeners, benzophenone hardeners, (B) The hardener may be used alone or in combination of two or more.

As the active ester curing agent, a compound having one or more active ester groups in one molecule can be used. Among them, the active ester curing agent is preferably a compound having two or more ester groups having high reactivity in one molecule, such as phenol esters, thiophenol esters, N-hydroxylamine esters, esters of heterocyclic hydroxyl compounds, etc. The active ester curing agent is preferably obtained by condensing a carboxylic acid compound and/or a thiocarboxylic acid compound with a hydroxyl compound and/or a thiol compound. In particular, from the viewpoint of improving heat resistance, an active ester curing agent obtained from a carboxylic acid compound and a hydroxyl compound is preferred, and an active ester curing agent obtained from a carboxylic acid compound and a phenol compound and/or a naphthol compound is more preferred.

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

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, phloroglucinol, benzenetriol, dicyclopentadiene-type diphenolic compounds, and phenol-novolac. Among them, "dicyclopentadiene-type diphenolic compounds" refers to diphenolic compounds obtained by condensing one molecule of dicyclopentadiene with two molecules of phenol.

Preferred specific examples of active ester hardeners include active ester hardeners containing a dicyclopentadiene diphenol structure, active ester hardeners containing a naphthalene structure, active ester hardeners containing acetylated phenol-novolac, active ester hardeners containing benzoylated phenol-novolac, etc. Among them, active ester hardeners containing a naphthalene structure and active ester hardeners containing a dicyclopentadiene diphenol structure are preferred. "Dicyclopentadiene diphenol structure" refers to a divalent structural unit formed by phenylene-dicyclopentylene-phenylene.

Among the commercially available active ester hardeners, there are active ester hardeners containing a dicyclopentadiene-type diphenol structure, such as "EXB9451", "EXB9460", "EXB9460S", "HPC8000-65T", "HPC8000H-65TM", "EXB8000L-65TM", "EXB8150-65T" (manufactured by DIC Corporation); active ester hardeners containing a naphthalene structure, such as "EXB9416-70BK" (manufactured by DIC Corporation); active ester hardeners containing acetylated phenol-phenol novolacs; Chemical agents, such as "DC808" (manufactured by Mitsubishi Chemical Corporation); active ester hardeners containing benzoyl compounds of phenol-phenol novolacs, such as "YLH1026" (manufactured by Mitsubishi Chemical Corporation); active ester hardeners containing acetylated compounds of phenol-phenol novolacs, such as "DC808" (manufactured by Mitsubishi Chemical Corporation); active ester hardeners containing benzoyl compounds of phenol-phenol novolacs, such as "YLH1026" (manufactured by Mitsubishi Chemical Corporation), "YLH1030" (manufactured by Mitsubishi Chemical Corporation), "YLH1048" (manufactured by Mitsubishi Chemical Corporation); etc.

Phenol-based hardeners and naphthol-based hardeners are preferably those having a novolac structure from the viewpoint of heat resistance and water resistance. Also, nitrogen-containing phenol-based hardeners are preferably those having a tri-phenol structure from the viewpoint of adhesion to the conductive layer. Phenolic hardeners are preferred for the skeleton.

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

Benzene Specific examples of hardeners include "ODA-BOZ" manufactured by JFE Chemical Company, "HFB2006M" manufactured by Showa High Polymer Corporation, "Pd" and "Fa" manufactured by Shikoku Chemical Industry Co., Ltd.

Cyanate curing agents, for example, bifunctional cyanate resins such as bisphenol A dicyanate, polyphenol cyanate, oligo(3-methyl-1,5-phenylene cyanate), 4,4'-methylbis(2,6-dimethylphenyl cyanate), 4,4'-ethylenediphenyl dicyanate, hexafluorobisphenol A dicyanate, 2,2-bis(4-cyanate)phenylpropane, 1,1-bis(4-cyanatephenylmethane), 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; some of these cyanate resins form tris- Specific examples of cyanate curing agents include: "PT30" and "PT60" (phenol-novolac type multifunctional cyanate resins), "ULL-950S" (multifunctional cyanate resins), "BA230", "BA230S75" (a part or all of bisphenol A dicyanate forming a tri-functional cyanate resin) manufactured by LONZA JAPAN Co., Ltd. prepolymer of chemical trimer) etc.

Specific examples of carbodiimide-based hardeners include "V-03", "V-05", "V-07", and "V-09" manufactured by Nisshinbo Chemical Co., Ltd.; and Stabaxol (registered trademark) P manufactured by LENXESS.

Amine-based hardeners include hardeners having more than one amine group in one molecule, such as aliphatic amines, polyether amines, alicyclic amines, aromatic amines, etc. Among them, aromatic amines are preferred in terms of achieving the desired effect of the present invention. Amine-based hardeners are preferably primary amines or secondary amines, and primary amines are more preferred. Specific examples of amine curing agents include: 4,4'-diaminodiphenylamine, diphenyldiaminosulfonate, 4,4'-diaminodiphenylmethane, 4,4'-diaminodiphenylsulfonate, 3,3'-diaminodiphenylsulfonate, m-diphenylenediamine, m-xylenediamine, diethyltoluenediamine, 4,4'-diaminodiphenyl ether, 3,3'-dimethyl-4,4'-diaminobiphenyl, 2,2'-dimethyl-4,4'-diaminobiphenyl, 3,3'-dihydroxybenzidine, 2,2-bis(3-amino bis(4-aminophenoxy)phenyl)sulfone, bis(4-(4-aminophenoxy)phenyl)sulfone, and the like. Amine hardeners may be commercially available products, such as "KAYABOND C-200S", "KAYABOND C-100", "Kayahard A-A", "Kayahard A-B", "Kayahard A-S" manufactured by Nippon Kayaku Co., Ltd., and "Epicure W" manufactured by Mitsubishi Chemical Corporation.

Examples of acid anhydride curing agents include curing agents having one or more acid anhydride groups in one molecule. Specific examples of acid anhydride curing agents include phthalic anhydride, tetrahydrophthalic anhydride, hexahydrophthalic anhydride, methyltetrahydrophthalic anhydride, methylhexahydrophthalic anhydride, methylnadic anhydride, hydrogenated methylnadic anhydride, trialkyltetrahydrophthalic anhydride, dodecenylsuccinic anhydride, 5-(2,5-dioxo-3-furanyl)-3-methyl-3-cyclohexene-1,2-dicarboxylic anhydride, trimellitic anhydride, pyromellitic anhydride, benzophenone tetracarboxylic anhydride, biphenyl tetracarboxylic anhydride, naphthalene tetracarboxylic anhydride, oxydiphthalic anhydride, 3,3 Polymer-type acid anhydrides include '-4,4'-diphenylsulfonate tetracarboxylic dianhydride, 1,3,3a,4,5,9b-hexahydro-5-(tetrahydro-2,5-dioxo-3-furanyl)-naphthalene[1,2-c]furan-1,3-dione, ethylene glycol bis(dehydrated trimellitate), styrene-maleic acid resin obtained by copolymerization of styrene and maleic acid, etc.

Among the above, (B) hardener can significantly achieve the desired effect of the present invention. In particular, phenol hardener, active ester hardener, carbodiimide hardener, benzophenone hardener, Preferably, at least one selected from the hardener is used.

The content ratio of (A) epoxy resin to (B) hardener, i.e., the ratio of [the total number of epoxy groups in (A) component]:[the total number of reactive groups in (B) hardener], is preferably in the range of 1:0.01 to 1:20, more preferably 1:0.05 to 1:10, and even more preferably 1:0.1 to 1:8. The "number of epoxy groups in (A) epoxy resin" refers to the total value of the mass of the non-volatile components of (A) epoxy resin present in the resin composition divided by the epoxy equivalent. Furthermore, "the active group number of (B) hardener" refers to the total value of the mass of the non-volatile components of the (B) hardener present in the resin composition divided by the active group equivalent. When the content ratio of the (A) epoxy resin to the (B) hardener is within this range, the expected effect of the present invention can be significantly obtained, and the heat resistance of the hardened material of the resin composition layer can generally be further improved.

(B) From the viewpoint of remarkably obtaining the expected effect of the present invention, the content of the hardener is preferably 0.1% by mass or more, more preferably 0.3% by mass or more, particularly preferably 0.5% by mass or more, preferably 20% by mass or less, more preferably 15% by mass or less, and particularly preferably 10% by mass or less, relative to 100% by mass of the non-volatile components in the resin composition.

<(C) Styrene elastomer> The resin composition contains (C) styrene elastomer. The content of styrene units in the (C) styrene elastomer is 61% by mass or more when the (C) component is 100% by mass. Since the (C) styrene elastomer contains 61% by mass or more of styrene units, the compatibility with (A) epoxy resin, (B) hardener, and (D) resin having a free radical polymerizable unsaturated group can be improved. Therefore, the phase separation between the (A) component and the (B) component and the (D) component can be suppressed. Therefore, the storage stability of the resin coating can be improved.

The content of styrene units in the (C) styrene-based elastomer is 61% by mass or more, preferably 63% by mass or more, and more preferably 65% by mass or more, when the (C) component is 100% by mass. The upper limit is preferably 80% by mass or less, more preferably 75% by mass or less, and particularly preferably 70% by mass or less. When the content of styrene units is within this range, the compatibility of the (A) epoxy resin and the (B) hardener with the (D) component can be improved, and as a result, the storage stability of the resin coating can be improved. The content of the aforementioned styrene units can be measured, for example, by weighing the amount of monomers added to constitute the (C) component.

(C) Styrene-based elastomers may be any elastomer containing repeating units (styrene units) having a structure obtained by polymerizing styrene. (C) Styrene-based elastomers may be copolymers containing styrene units and any repeating units different from the styrene units which may be combined with the styrene units.

The arbitrary repeating units include, for example, repeating units having a structure obtained by polymerization of conjugated dienes (conjugated diene units), repeating units having a structure obtained by hydrogenation of the conjugated dienes (hydrogenated conjugated diene units), and the like.

Examples of the conjugated diene include aliphatic conjugated dienes such as butadiene, isoprene, 2,3-dimethylbutadiene, 1,3-pentadiene, and 1,3-hexadiene; and halogenated aliphatic conjugated dienes such as chloroprene. The conjugated diene can significantly achieve the effect of the present invention, and aliphatic conjugated dienes are preferred, and butadiene is more preferred. The conjugated diene may be used alone or in combination of two or more.

(C) Styrene elastomers may be random copolymers, but block copolymers are preferred in order to significantly obtain the effects of the present invention. (C) Styrene elastomers may be styrene-copolymerized diene block copolymers or hydrogenated styrene-copolymerized diene copolymers. (C) Styrene elastomers are particularly preferred, and examples thereof include block copolymers having at least one polymer block containing styrene units as terminal blocks and at least one polymer block containing copolymerized diene units or hydrogenated copolymerized diene units as middle blocks.

The hydrogenated styrene-covalent diene block copolymer refers to a block copolymer having a structure in which the unsaturated bonds of the styrene-covalent diene block copolymer are hydrogenated. Generally, the hydrogenated styrene-covalent diene block copolymer is one in which the unsaturated bonds of the aliphatic group are hydrogenated, while the unsaturated bonds of the aromatic group such as the benzene ring are not hydrogenated.

(C) Specific examples of styrene-based elastomers include styrene-butadiene-styrene block copolymers (SBS), styrene-isoprene-styrene block copolymers (SIS), styrene-ethyl-butylene-styrene block copolymers (SEBS), styrene-ethyl-propylene-styrene block copolymers (SEPS), styrene-ethyl-ethyl-propylene-styrene block copolymers (SEEPS), styrene-butadiene-butylene-styrene block copolymers (SBBS), styrene-butadiene diblock copolymers, hydrogenated styrene-butadiene block copolymers, hydrogenated styrene-isoprene block copolymers, hydrogenated styrene-butadiene random copolymers, and the like.

The weight average molecular weight (Mw) of the (C) styrene elastomer is preferably 1,000 to 500,000, more preferably 2,000 to 300,000, and particularly preferably 3,000 to 200,000, in order to significantly obtain the expected effect of the present invention. The weight average molecular weight of the (C) styrene elastomer can be measured in the same manner as the weight average molecular weight of the (A) epoxy resin.

As the component (C), commercially available products may be used, for example, hydrogenated styrene-based thermoplastic elastomers "Tuftec H1043" and "Tuftec P2000" (manufactured by Asahi Kasei Corporation); styrene-based thermoplastic elastomer "Septon 2104" (manufactured by KURARAY Corporation), etc. The component (C) may be used alone or in combination of two or more.

The content of component (C) is preferably 0.1% by mass or more, more preferably 0.3% by mass or more, and particularly preferably 0.5% by mass or more, when the non-volatile components in the resin composition are set to 100% by mass, in order to significantly obtain the effect of the present invention. The upper limit is preferably 18% by mass or less, more preferably 15% by mass or less, particularly preferably 10% by mass or less, and most preferably 4% by mass or less.

When the non-volatile components in the resin composition of the component (C) are taken as 100% by mass, the content thereof is C1, and when the non-volatile components in the resin composition of the component (B) are taken as 100% by mass, the content thereof is B1. In this case, the effect of the present invention can be significantly obtained, and C1/B1 is preferably 0.01 or more, more preferably 0.05 or more, particularly preferably 0.1 or more, preferably 10 or less, more preferably 5 or less, and particularly preferably 3 or less.

<(D) Resin with free radical polymerizable unsaturated groups> The resin composition is a resin containing (D) a resin with free radical polymerizable unsaturated groups. When the resin containing (D) a resin with free radical polymerizable unsaturated groups is used as the resin composition, a cured product with a low loss factor can be obtained. However, when the resin containing (D) a resin with free radical polymerizable unsaturated groups is used, the cured product can reduce the general loss factor. On the other hand, the (D) component will cause the (A) component and the (B) component to phase separate, which will tend to reduce the storage stability of the resin coating. However, in the present invention, since the (C) component is also combined, the phase separation can be suppressed, so a cured product with excellent storage stability of the resin coating and a low loss factor can be obtained.

The free radical polymerizable unsaturated group refers to a group with an ethylene double bond that can be cured by irradiation with active energy rays. These groups include vinyl, vinylphenyl, acryl, methacryl, maleimide, fumaryl, maleyl, etc., and at least one selected from vinylphenyl, acryl, and methacryl is preferred. Among them, acryl and methacryl are also collectively referred to as "(meth)acryl". In addition, vinylphenyl is a group having the structure shown below. (＊indicates key binding).

(D) From the viewpoint that a resin having free radical polymerizable unsaturated groups can produce a cured product having a low loss factor, it is preferred that the resin has two or more free radical polymerizable unsaturated groups per molecule.

(D) From the viewpoint that a resin having a free radical polymerizable unsaturated group can produce a cured product with a low loss factor, it is preferred that the resin has a cyclic structure. The cyclic structure is preferably a divalent cyclic group. The divalent cyclic group may be any of a cyclic group containing an alicyclic structure and a cyclic group containing an aromatic cyclic structure. Furthermore, the divalent cyclic group may have a plurality of groups.

From the viewpoint that the effects expected by the present invention can be significantly obtained with a divalent cyclic group, it is preferably 3-membered or more, more preferably 4-membered or more, particularly preferably 5-membered or more, preferably 20-membered or less, more preferably 15-membered or less, particularly 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 be a ring whose skeleton is composed of heteroatoms other than carbon atoms. Heteroatoms include oxygen atoms, sulfur atoms, nitrogen atoms, etc., and oxygen atoms are preferred. The heteroatoms in the ring may be one or two or more.

Specific examples of the divalent cyclic group include the following divalent groups (i) to (xiii). (In the divalent groups (xii) and (xiii), R ¹ , R ² , R ⁵ , R ⁶ , R ⁷ , R ¹¹ , and R ¹² each independently represent a halogen atom, an alkyl group having 6 or less carbon atoms, or a phenyl group; R ³ , R ⁴ , R ⁸ , R ⁹ , and R ¹⁰ each independently represent a hydrogen atom, a halogen atom, an alkyl group having 6 or less carbon atoms, or a phenyl group).

Halogen atoms include fluorine atoms, chlorine atoms, bromine atoms, and iodine atoms. Alkyl groups with carbon atoms of 6 or less include methyl, ethyl, propyl, butyl, pentyl, and hexyl groups, and methyl groups are preferred. ^R1 , ^R2 , ^R5 , ^R6 , ^R7 , ^R11 , and ^R12 are preferably methyl groups. ^R3 , ^R4 , ^R8 , ^R9 , and ^R10 are preferably hydrogen atoms or methyl groups.

The divalent cyclic group may be a combination of plural divalent cyclic groups. Specific examples of the combination of divalent cyclic groups include a divalent cyclic group represented by the following formula (a) (divalent group (a)). (In formula (a), R ²¹ , R ²² , R ²⁵ , R ²⁶ , R ²⁷ , R ³¹ , R ³² , R ³⁵ and R ³⁶ each independently represent a halogen atom, an alkyl group having 6 or less carbon atoms, or a phenyl group; R ²³ , R ²⁴ , R ²⁸ , R ²⁹ , R ³⁰ , R ³³ and R ³⁴ each independently represent a hydrogen atom, a halogen atom, an alkyl group having 6 or less carbon atoms, or a phenyl group. n and m represent integers from 0 to 300. However, the case where one of n and m is 0 is not included).

R ²¹ , R ²² , R ³⁵ and R ³⁶ are the same as R ¹ in the divalent group (xii). R ²³ , R ²⁴ , R ³³ and R ³⁴ are the same as R ³ in the divalent group (xii). R ²⁵ , R ²⁶ , R ²⁷ , R ³¹ and R ³² are the same as R ⁵ in the formula (xiii). R ²⁸ , R ²⁹ and R ³⁰ are the same as R ⁸ in the formula (xiii).

n and m represent integers from 0 to 300. However, this does not include the case where one of n and m is 0. n and m preferably represent integers from 1 to 100, more preferably represent integers from 1 to 50, and even more preferably represent integers from 1 to 10. n and m may be the same or different.

The divalent cyclic group is preferably a divalent group (x), a divalent group (xi), or a divalent group (a), and more preferably a divalent group (x) or a divalent group (a).

The divalent cyclic group may have a substituent. Examples of such substituents include halogen atoms, alkyl groups, alkoxy groups, aryl groups, aralkyl groups, silyl groups, acyl groups, acyloxy groups, carboxyl groups, sulfonic acid groups, cyano groups, nitro groups, hydroxyl groups, thio groups, and pendoxy groups, and alkyl groups are preferred.

The free radical polymerizable unsaturated group may be directly bonded to the divalent cyclic group or may be bonded via a divalent linking group. The divalent linking group may be exemplified by 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 obtained by combining these groups in plural numbers. 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, 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 chain, and a cyclic chain. The alkylene groups include, for example, methylene, ethylene, propylene, butylene, pentylene, hexylene, 1,1-dimethylethylene, etc., and methylene, ethylene, and 1,1-dimethylethylene are preferred. The alkenylene groups are preferably alkenylene groups having 2 to 10 carbon atoms, more preferably alkenylene groups having 2 to 6 carbon atoms, and more preferably alkenylene groups having 2 to 5 carbon atoms. The arylene groups and heteroarylene groups are preferably arylene groups or heteroarylene groups having 6 to 20 carbon atoms, and more preferably arylene groups or heteroarylene groups having 6 to 10 carbon atoms. The divalent linking group is preferably an alkylene group, and methylene and 1,1-dimethylethylene are preferred.

(D) The resin having a radical polymerizable unsaturated group is preferably represented by the following formula (1). (In formula (1), ^R1 and ^R4 each independently represent a free radical polymerizable unsaturated group, ^R2 and ^R3 each independently represent a divalent linking group. Ring A represents a divalent cyclic group).

^R1 and ^R4 each independently represent a free radical polymerizable unsaturated group, and preferably vinylphenyl or (meth)acryloyl.

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

Ring A represents a divalent cyclic group. Ring A has the same contents as the above-mentioned divalent cyclic group.

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

The following are specific examples of component (D), but the present invention is not limited to these contents. (n1 is the same as n in formula (a), and m1 is the same as m in formula (a)).

As the component (D), commercial products may be used, for example, "OPE-2St" manufactured by Mitsubishi Gas Chemical Co., Ltd., "A-DOG" manufactured by Shin-Nakamura Chemical Co., Ltd., "DCP-A" manufactured by Kyoeisha Chemical Co., Ltd., etc. The component (D) may be used alone or in combination of two or more.

The number average molecular weight of the component (D) is preferably 3000 or less, more preferably 2500 or less, particularly preferably 2000 or less, and most preferably 1500 or less, in order to remarkably obtain the expected effect of the present invention. The lower limit is preferably 100 or more, more preferably 300 or more, particularly preferably 500 or more, and most preferably 1000 or more. The number average molecular weight is the number average molecular weight in terms of polystyrene measured by gel permeation chromatography (GPC).

The content of component (D) is preferably 5% by mass or more, more preferably 10% by mass or more, and particularly preferably 15% by mass or more, when the non-volatile components in the resin composition are set to 100% by mass, in order to significantly obtain the effect of the present invention. The upper limit is preferably 50% by mass or less, more preferably 40% by mass or less, and particularly preferably 30% by mass or less.

<(E) Inorganic filler> The resin composition may contain (E) an inorganic filler as an optional component in addition to the above components.

The material of the inorganic filler is an inorganic compound. Examples of the material of the inorganic filler include: silicon dioxide, alumina, glass, cordierite, silicate, barium sulfate, barium carbonate, talc, clay, mica powder, zinc oxide, hydrotalcite, alumina, aluminum hydroxide, magnesium hydroxide, calcium carbonate, magnesium carbonate, magnesium oxide, boron nitride, aluminum nitride, manganese nitride, aluminum borate, strontium carbonate, strontium titanate, calcium titanate, magnesium titanate, bismuth titanate, titanium oxide, zirconium oxide, barium titanate, barium zirconate, barium zirconate, calcium zirconate, zirconium phosphate, and zirconium tungstate phosphate. Among them, silicon dioxide is particularly suitable. Examples of silicon dioxide include amorphous silicon dioxide, fused silicon dioxide, crystalline silicon dioxide, synthetic silicon dioxide, and hollow silicon dioxide. Moreover, spherical silicon dioxide is preferred. (E) Inorganic fillers may be used alone or in combination of two or more.

(E) Commercially available inorganic fillers include: "UFP-30" manufactured by DENKA; "SP60-05" and "SP507-05" manufactured by Nippon Steel & Sumitomo Metal Materials Corporation; "YC100C", "YA050C", "YA050C-MJE" and "YA010C" manufactured by ADMATECHS; "Selfil NSS-3N", "Selfil NSS-4N" and "Selfil NSS-5N" manufactured by Tokuyama Corporation; "SC2500SQ", "SO-C4", "SO-C2" and "SO-C1" manufactured by ADMATECHS; etc.

(E) 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 particularly preferably 1 μm or less, in order to remarkably obtain the expected effect of the present invention.

(E) The average particle size of the inorganic filler can be measured using the laser diffraction/scattering method based on the Mie scattering theory. Specifically, the particle size distribution of the inorganic filler is obtained based on the volume standard using a laser diffraction/scattering particle size distribution measuring device, and then the median diameter is used as the average particle size for measurement. The measurement sample is a sample obtained by weighing 100 mg of the inorganic filler and 10 g of methyl ethyl ketone into a sample bottle, and then dispersing it with ultrasound for 10 minutes. The sample is measured using a laser diffraction particle size distribution measuring device, the wavelength of the light source used is blue and red, and the volume-based particle size distribution of the inorganic filler (E) is measured by the flow cell method, and the median diameter is calculated from the obtained particle size distribution as the average particle size. The laser diffraction particle size distribution measuring device is, for example, the "LA-960" manufactured by Horiba, Ltd.

(E) 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 expected 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 is obtained by adsorbing nitrogen gas on the surface of the sample using a specific surface area measuring device (Macsorb HM-1210 manufactured by MOUNTECH) according to the BET method, and then calculating the specific surface area using the BET multi-point method.

(E) Inorganic fillers are preferably treated with a surface treatment agent from the viewpoint of improving moisture resistance and dispersibility. The surface treatment agent includes, for example, fluorine-containing silane coupling agents, aminosilane-based coupling agents, epoxysilane-based coupling agents, hydrosulfide-based coupling agents, silane-based coupling agents, alkoxysilanes, organic silazane compounds, and titanium ester-based coupling agents. The surface treatment agent may be used alone or in any combination of two or more.

Commercially available surface treatment agents include: "KBM403" (3-glycidoxypropyltrimethoxysilane) manufactured by Shin-Etsu Chemical Co., Ltd., "KBM803" (3-mercaptopropyltrimethoxysilane) manufactured by Shin-Etsu Chemical Co., Ltd., "KBE903" (3-aminopropyltriethoxysilane) manufactured by Shin-Etsu Chemical Co., Ltd., "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 the surface treatment agent is preferably concentrated in a specific range from the viewpoint of improving the dispersibility of the inorganic filler. Specifically, for 100 parts by mass of the inorganic filler, it is preferred to use 0.2 to 5 parts by mass of the surface treatment agent for surface treatment, 0.2 to 3 parts by mass for surface treatment, and 0.3 to 2 parts by mass for surface treatment.

The degree of surface treatment by the surface treatment agent can also be evaluated by the amount of carbon per unit surface area of each inorganic filler. From the perspective of improving the dispersibility of the inorganic filler, the amount of carbon per unit surface area of each 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. On the other hand, from the perspective of suppressing the increase in the melt viscosity of the resin coating and the melt viscosity in the form of a sheet, 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 each inorganic filler can be measured by washing the surface treated inorganic filler with a solvent (such as methyl ethyl ketone (MEK)). Specifically, a sufficient amount of MEK can be added to the inorganic filler after surface treatment with a surface treatment agent, and then ultrasonically washed at 25°C for 5 minutes. After removing the clear liquid and drying the solid components, the amount of carbon per unit surface area of each inorganic filler can be measured using a carbon analyzer. A carbon analyzer such as "EMIA-320V" manufactured by Horiba, Ltd. can be used.

(E) From the viewpoint of reducing the loss coefficient, the content of the inorganic filler is preferably 50 mass % or more, more preferably 51 mass % or more, particularly preferably 52 mass % or more, preferably 90 mass % or less, more preferably 85 mass % or less, and particularly preferably 80 mass % or less, when the non-volatile components in the resin composition are set to 100 mass %.

<Styrene elastomer other than component (F)(C)> In addition to component (C), the resin composition may contain a styrene elastomer other than component (F)(C) within a range that does not affect the effect of the present invention. The styrene elastomer (F) other than component (C) means a styrene elastomer whose content of styrene units is less than 61% by mass when component (F) is 100% by mass. The elements other than the content of styrene units in component (F) may be as described in the column <(C) Styrene elastomer>.

The content of styrene units in the component (F) is less than 61% by mass, preferably less than 50% by mass, and particularly preferably less than 45% by mass, when the component (F) is 100% by mass. The lower limit is preferably 1% by mass, more preferably 5% by mass, and particularly preferably 10% by mass. The content of styrene units can be measured by adding, for example, the amount of monomers constituting the component (F).

The component (F) may be a commercially available product, for example, hydrogenated styrene-based thermoplastic elastomer "Tuftec MP10" (manufactured by Asahi Kasei Corporation); epoxidized styrene-butadiene thermoplastic elastomer "Epogrined AT501" (manufactured by DAICEL Corporation), etc. The component (F) may be used alone or in combination of two or more.

The content of the component (F) is preferably 1% by mass or more, more preferably 2% by mass or more, and particularly preferably 3% by mass or more, when the non-volatile components in the resin composition are set to 100% by mass, in order to significantly obtain the effect of the present invention. The upper limit is preferably 15% by mass or less, more preferably 13% by mass or less, and particularly preferably 10% by mass or less.

<(G) Hardening accelerator> The resin composition may contain (G) a hardening accelerator as an optional component in addition to the above components.

The hardening accelerator includes, for example, 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.

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., with triphenylphosphine and tetrabutylphosphonium decanoate being preferred.

Amine-based hardening accelerators, for example: trialkylamines such as triethylamine and tributylamine, 4-dimethylaminopyridine, benzyldimethylamine, 2,4,6-tris(dimethylaminomethyl)phenol, 1,8-diazabicyclo(5,4,0)-undecene, etc., with 4-dimethylaminopyridine and 1,8-diazabicyclo(5,4,0)-undecene being preferred.

Imidazole hardening accelerators, for example: 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 salt trimellitate, 1-cyanoethyl-2-phenylimidazole salt trimellitate, 2,4-diamino-6-[2'-methylimidazolyl-(1')]-ethyl-s-trimethylol , 2,4-diamino-6-[2'-undecylimidazolyl-(1')]-ethyl-s-tri , 2,4-diamino-6-[2'-ethyl-4'-methylimidazolyl-(1')]-ethyl-s-tri , 2,4-diamino-6-[2'-methylimidazolyl-(1')]-ethyl-s-tri Imidazole compounds such as isocyanuric acid adduct, 2-phenylimidazole isocyanuric acid adduct, 2-phenyl-4,5-dihydroxymethylimidazole, 2-phenyl-4-methyl-5-hydroxymethylimidazole, 2,3-dihydro-1H-pyrrolo[1,2-a]benzimidazole, 1-dodecyl-2-methyl-3-benzylimidazole salt chloride, 2-methylimidazoline, 2-phenylimidazoline, and adducts of imidazole compounds with epoxy resins, etc., with 2-ethyl-4-methylimidazole and 1-benzyl-2-phenylimidazole being preferred.

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

Guanidine-based hardening accelerators, for example: 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., and dicyandiamide and 1,5,7-triazabicyclo[4.4.0]dec-5-ene are preferred.

Metal hardening accelerators, such as organic metal complexes or organic metal salts of cobalt, copper, zinc, iron, nickel, manganese, tin, etc. Specific examples of the organometallic complexes include organic cobalt complexes such as cobalt (II) acetylacetone (salt) and cobalt (III) acetylacetone (salt); organic copper complexes such as copper (II) acetylacetone (salt); organic zinc complexes such as zinc (II) acetylacetone (salt); organic iron complexes such as iron (III) acetylacetone (salt); organic nickel complexes such as nickel (II) acetylacetone (salt); and organic manganese complexes such as manganese (II) acetylacetone (salt). Organic metal salts include zinc octylate, tin octylate, zinc cycloate, cobalt cycloate, tin stearate, zinc stearate, etc.

(G) From the viewpoint of remarkably obtaining the expected effect of the present invention, the content of the hardening accelerator is preferably 0.01% by mass or more, more preferably 0.03% by mass or more, particularly preferably 0.05% by mass or more, preferably 0.3% by mass or less, more preferably 0.2% by mass or less, and particularly preferably 0.1% by mass or less, when the non-volatile components in the resin composition are set to 100% by mass.

＜(H) Polymerization initiator＞ In addition to the above components, the resin composition may further contain (H) polymerization initiator as an optional component. (H) polymerization initiator is usually in (D) component and has the function of promoting free radical polymerization unsaturated group crosslinking. (H) polymerization initiator may be used alone or in combination of two or more.

(H) A polymerization initiator, for example, peroxides such as t-butyl isopropyl peroxide, t-butyl peroxyacetate, α,α’-di(t-butylperoxy)diisopropylbenzene, t-butyl peroxylaurate, t-butyl peroxy-2-ethylhexanoate, t-butyl peroxyneodecanoate, and t-butyl peroxybenzoate.

(H) Commercially available products of polymerization initiators include, for example, "Perbutyl C", "Perbutyl A", "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% by mass or more, more preferably 0.05% by mass or more, particularly preferably 0.1% by mass or more, preferably 1% by mass or less, more preferably 0.5% by mass or less, and particularly preferably 0.4% by mass or less, when the non-volatile component in the resin composition is 100% by mass, so as to remarkably obtain the expected effect of the present invention.

<(I) Other additives> In addition to the above components, the resin composition may contain other additives as arbitrary components. Such additives include, for example, thermoplastic resins (but excluding components (C), (D) and (F)); organic fillers; resin additives such as thickeners, defoamers, leveling agents, adhesion agents, etc. These additives may be used alone or in combination of two or more.

<Physical properties and uses of resin compositions> Resin coatings obtained by dissolving resin compositions in organic solvents show excellent storage stability and other characteristics. For example, after the resin coating is placed at 5°C for 100 hours, even if it is returned to room temperature, usually no coagulation larger than 1 mm can be observed in the resin coating.

The resin composition is heat cured at 200°C for 90 minutes to form a cured product with a lower loss coefficient. Therefore, the cured product can form an insulating layer with a low loss coefficient. The loss coefficient is preferably less than 0.005, more preferably less than 0.0045, and particularly preferably less than 0.004. On the other hand, the lower limit of the loss coefficient is not particularly limited, and is generally, for example, greater than 0.0001. The evaluation of the loss coefficient can be measured according to the method described in the embodiment described below.

The cured product after the resin composition is heat-cured at 130°C for 30 minutes and then at 170°C for 30 minutes can usually show excellent adhesion strength (peel strength) and other characteristics between the coated conductive layer. Therefore, the aforementioned cured product and the coated conductive layer can form an insulating layer with excellent peel strength. The peel strength is preferably above 0.3kgf/cm, more preferably above 0.4kgf/cm, and particularly preferably above 0.5kgf/cm. On the other hand, the upper limit of the peel strength is not particularly limited, and is generally, for example, below 5kgf/cm. The evaluation of the aforementioned peel strength can be measured according to the method described in the embodiments described below.

The resin composition of the present invention, in addition to having a low loss factor, can also generally form an insulating layer with a greater peel strength. Therefore, the resin composition of the present invention is suitable as a resin composition for insulating purposes. Specifically, it is suitable for use as a resin composition that can form an insulating layer, and the insulating layer is used to form a conductive layer (including a redistribution layer (RDL)) thereon (the resin composition is used as an insulating layer for the purpose of forming a conductive layer).

Furthermore, in the multi-layer printed wiring board described later, it is suitable as a resin composition for forming an insulating layer of the multi-layer printed wiring board (resin composition for forming insulating layer of multi-layer printed wiring board), a resin composition for forming an interlayer insulating layer of the printed wiring board (resin composition for forming interlayer insulating layer of printed wiring board), etc. Among them, it is particularly preferred to be a resin composition for forming an insulating layer for forming a via hole having a top diameter of 45 μm or less, and it is most preferred to be a resin composition for forming an insulating layer having a thickness of 20 μm or less.

Furthermore, for example, when a semiconductor package chip is manufactured through the following steps (1) to (6), the resin composition of the present invention is also suitable for use as a resin composition for a wire redistribution layer (resin composition for forming a wire redistribution layer) as an insulating layer for forming a wire redistribution layer (RDL), and a resin composition for semiconductor chip packaging (resin composition for semiconductor package chip). When manufacturing a semiconductor package chip, a wire redistribution layer (RDL) can be formed on the packaging layer. (1) laminating a pseudo-fixing film on a substrate, (2) pseudo-fixing a semiconductor chip on the pseudo-fixing film, (3) forming a packaging layer on the semiconductor chip, (4) peeling the substrate and the pseudo-fixing film off the semiconductor chip, (5) forming a wire redistribution layer as an insulating layer on the surface of the substrate and the pseudo-fixing film from which the semiconductor chip is peeled, and (6) forming a wire redistribution layer (RDL) as a conductive layer on the wire redistribution layer

Furthermore, the resin composition of the present invention can produce an insulating layer with good component embedding properties, and is therefore suitable for use even when the printed wiring board is a circuit board with built-in components.

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

The thickness of the resin composition layer is preferably 30 μm or less, more preferably 20 μm or less, particularly preferably 15 μm or less, and most preferably 10 μm or less, from the viewpoints of thinning the printed wiring board and providing a cured product with excellent insulation even when the cured product of the resin composition is a thin film. There is no particular lower limit to the thickness of the resin composition layer, and it is usually, for example, 1 μm or more, 5 μm or more, etc.

The supporting body may be, for example, a film formed of a plastic material, a metal foil, a release paper, etc., and a film formed of a plastic material and a metal foil are preferred.

When the support uses a film formed of a plastic material, the plastic material may include polyesters such as polyethylene terephthalate (hereinafter, also referred to as "PET") and polyethylene naphthyl ester (hereinafter, also referred to as "PEN"); acrylates such as polycarbonate (hereinafter, also referred to as "PC") and polymethyl methacrylate (PMMA); cyclic polyolefin, triacetyl cellulose (TAC), polyether sulfide (PES), polyether ketone, polyimide, etc. Among them, polyethylene terephthalate and polyethylene naphthyl ester are preferred, and inexpensive polyethylene terephthalate is particularly preferred.

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

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

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

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

In one embodiment, the resin sheet may also contain other layers when necessary. The other layers include, for example, a protective film that is disposed on the surface of the resin composition layer that is not bonded to the support body (i.e., the surface on the opposite side of the support body) and is regarded as a quasi-support body. The thickness of the protective film is not particularly limited, and is generally 1 μm to 40 μm. When the protective film is laminated, it can inhibit impurities from adhering to the surface of the resin composition layer, or inhibit wear, etc.

The resin sheet can be prepared, for example, by first preparing a resin coating obtained by dissolving a resin composition in an organic solvent, then coating the resin coating on a support using a slit coating machine, and then drying the resin coating to form a resin composition layer.

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

The drying method can be implemented by known methods such as heating and blowing hot air. There is no particular limitation on the drying conditions. Generally, the drying is performed in such a way that the content of the organic solvent in the resin composition layer is less than 10 mass %, preferably less than 5 mass %. It varies depending on the boiling point of the organic solvent in the resin coating. Generally, for example, when a resin coating containing 30 mass % to 60 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 in a rolled-up form. If the resin sheet has a protective film, the protective film can be peeled off before use.

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

A printed wiring board, for example, can be produced using the above-mentioned resin sheet according to a method comprising the following steps (I) and (II). (I) A step of laminating a resin composition layer of the resin sheet on an inner substrate and bonding it 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 constituting the substrate of the printed wiring board, which can be exemplified by: glass epoxy substrate, metal substrate, polyester substrate, polyimide substrate, BT resin substrate, thermosetting polyphenylene ether substrate, etc. In addition, the substrate may have a conductive layer on one side or both sides, or the conductive layer may be processed by graphics. The inner layer substrate with a conductive layer (circuit) formed on one side or both sides of the substrate is also called an "inner layer circuit substrate". In addition, the intermediate product of the insulating layer and/or conductive layer formed during the manufacture of the printed wiring board is also included in the "inner layer substrate" referred to in the present invention. When the printed wiring board is a circuit board with built-in components, an inner substrate with built-in components can also be used.

The inner substrate and the resin sheet can be laminated, for example, by heat-pressing the resin sheet to the inner substrate from the side of the support. The component for heat-pressing the resin sheet to the inner substrate (hereinafter also referred to as "heat-pressing component") can be, for example, a heated metal plate (SUS mirror plate, etc.) or a metal roller (SUS roller). In addition, the heat-pressing component is not to directly press the resin sheet, but preferably to press the resin sheet through an elastic material such as heat-resistant rubber so that the resin sheet fully follows the surface unevenness of the inner substrate.

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

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

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

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

In step (II), the resin composition layer may be 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 may 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 generally preferably 120°C to 240°C, more preferably 150°C to 220°C, and particularly preferably 170°C to 210°C. The curing time is preferably 5 minutes to 120 minutes, more preferably 10 minutes to 100 minutes, and particularly preferably 15 minutes to 100 minutes.

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

Since the insulating layer is formed by using the cured product of the resin composition of the present invention, the thickness of the insulating layer can be made thinner. The thickness of the insulating layer is preferably 30 μm or less, more preferably 20 μm or less, particularly preferably 15 μm or less, and most preferably 10 μm or less. The lower limit is not particularly limited, and can usually be 1 μm or more, 5 μm or more, etc.

When manufacturing a printed wiring board, the following steps may be further performed: (III) a step of opening holes in the insulating layer, (IV) a step of roughening the insulating layer, (V) a step of forming a conductive layer, etc. These steps (III) to (V) may be performed according to various methods known to the industry when manufacturing printed wiring boards. Furthermore, when the support is removed after step (II), the support may be removed between step (II) and step (III), between step (III) and step (IV), or between step (IV) and step (V). Furthermore, if necessary, the formation of the insulating layer and the conductive layer in steps (II) to (V) can be repeated to form a multi-layer wiring board.

Step (III) is a step of opening holes in the insulating layer. In this way, holes such as via holes and through holes can be formed on the insulating layer. Step (III) can be carried out in accordance with the composition of the resin composition used to form the insulating layer, for example, by using a drill, laser, plasma, etc. The size or shape of the hole can be appropriately determined in accordance with the design of the printed wiring board.

Since the insulating layer is formed by using the hardened resin composition of the present invention, the top diameter can be made smaller. The top diameter of the aforementioned hole is preferably 45 μm or less, more preferably 40 μm or less, and particularly preferably 35 μm or less. The lower limit can be 1 μm or more.

Step (IV) is a step of roughening the insulating layer. Usually, in step (IV), slag is also removed. There is no particular limitation on the sequence and conditions of the roughening treatment, and the known sequence and conditions commonly used when forming the insulating layer of the printed wiring board can be used. In addition, either a dry process or a wet process can be used. When the conductive layer is formed by sputtering, dry treatment such as slag removal using plasma is preferred. In particular, when the above-mentioned resin composition is used for the opening treatment in step (III) using UV (ultraviolet) laser, it is preferred to use dry slag removal because it has the tendency to effectively suppress slag.

Gas used for sputtering may be, for example, argon, oxygen, CF ₄ , etc. These may be used alone or in combination of two or more.

In one embodiment, the arithmetic mean roughness (Ra) of the insulating layer surface after the roughening treatment is preferably less than 400nm, more preferably less than 350nm, and particularly preferably less than 300nm. The lower limit is not particularly limited, and is preferably greater than 0.5nm, and more preferably greater than 1nm. In addition, the root mean square roughness (Rq) of the insulating layer surface after the roughening treatment is preferably less than 400nm, more preferably less than 350nm, and particularly preferably less than 300nm. The lower limit is not particularly limited, and is preferably greater than 0.5nm, and more preferably greater than 1nm. The arithmetic mean roughness (Ra) and root mean square roughness (Rq) of the insulating layer surface can be measured using a non-contact surface roughness meter.

Step (V) is a step of forming a conductive layer, which is to form a conductive layer on the insulating layer. The conductive material used for the conductive layer is not particularly limited. In a preferred embodiment, the conductive layer contains 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 may be a single metal layer or an alloy layer. The alloy layer may be, for example, a layer formed of 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 versatility, cost, and ease of patterning in forming a conductive layer, 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, and 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.

The conductive layer may be a single layer structure, or a multi-layer structure in which two or more single metal layers or alloy layers formed of different types of metals or alloys are laminated. When the conductive layer is a multi-layer structure, the layer that is bonded to 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 varies depending on the desired design of the printed wiring board, but is generally 3 μm to 35 μm, preferably 5 μm to 30 μm.

In one embodiment, the conductive layer can be formed by sputter plating. In the sputter plating method, a conductive thin layer is first formed on the surface of the insulating layer by sputter plating, and then a conductive sputter plating layer is formed on the conductive thin layer by sputter plating. Before forming the conductive thin layer by sputter plating, a back sputter plating treatment can be performed to clean the surface of the insulating layer. The gas used in the back sputter plating can be various gases, but Ar, _O2 , and _N2 are preferred. When the thin sheet layer is Cu and Cu alloy, it is preferred to use Ar or _O2 or Ar, _O2 mixed gas; when the thin sheet layer is Ti, it is preferred to use Ar or _N2 or Ar, _N2 mixed gas; when the thin sheet layer is Cr and Cr alloy (nickel-chromium alloy, etc.), it is preferred to use Ar or _O2 or Ar, _O2 mixed gas. Sputtering can be performed using various sputtering devices such as microwave sputtering and mirrortron sputtering. Metals forming the conductive thin sheet layer include Cr, Ni, Ti, nickel-chromium alloy, etc. Cr and Ti are particularly preferred. The thickness of the conductive thin sheet layer is usually preferably formed to be 5 nm or more, more preferably to be formed to be 10 nm or more, preferably to be formed to be 1000 nm or less, and more preferably to be formed to be 500 nm or less. The metal forming the conductor sputtering layer may be, for example, Cu, Pt, Au, Pd, etc. In particular, Cu is preferred. The thickness of the conductor sputtering layer is usually preferably formed to be 50 nm or more, more preferably to be formed to be 100 nm or more, preferably to be formed to be 3000 nm or less, and more preferably to be formed to be 1000 nm or less.

When forming a conductive thin layer, the surface roughness (Ra value) formed on the surface of the insulating layer can be measured after the conductive thin layer is removed by etching. The value is preferably below 150nm, preferably in the range of 10 to 150nm, and even more preferably below 10 to 120nm.

After forming the conductor layer by sputtering, a copper-plated layer may be formed on the conductor layer by electrolytic copper plating. The thickness of the copper-plated layer is preferably 5 μm or more, more preferably 8 μm or more, preferably 75 μm or less, and more preferably 35 μm or less. The circuit formation method may be a known method such as a subtractive process or a semi-additive process.

In another embodiment, the conductive layer can be formed by using a metal foil. When the conductive layer is formed by using a metal foil, the step (V) is preferably performed between the step (I) and the step (II). For example, after the step (I), the support is removed, and the metal foil is laminated on the surface of the exposed resin composition layer. The lamination method of the resin composition layer and the metal foil can be performed by using a vacuum lamination method. The lamination conditions can be the same as the lamination conditions of the inner substrate and the resin sheet. Subsequently, the step (II) is performed to form the insulating layer. Subsequently, a subtractive process, a modified-semi-additive process (MSAP), etc. are used to form a conductive layer with the desired wiring pattern.

Metal foil can be produced by known methods such as electrolysis and rolling. Examples of metal foil include copper foil and aluminum foil, with copper foil being preferred. Copper foil can be made of copper alone or alloys of copper and other metals (such as tin, chromium, silver, magnesium, nickel, zirconium, silicon, titanium, etc.). Commercially available metal foils include HLP foil and JXUT-III foil manufactured by JX Metal Corporation, and 3EC-III and TP-III foil manufactured by Mitsui Mining and Metals Co., Ltd.

In another embodiment, the conductive layer can be formed by plating. For example, a conductive layer having a desired wiring pattern can be formed by plating on the surface of the insulating layer using a conventionally known technique such as a semi-additive method or a fully additive method. From the perspective of simplicity in manufacturing, it is preferred to use a semi-additive method. The following is an example of a conductive layer formed by a semi-additive method.

First, a coating thin layer is formed on the surface of the insulating layer by electroless plating. Next, a mask pattern of the exposed portion of the coating thin layer corresponding to the desired wiring pattern is formed on the formed coating thin layer. A metal layer is then formed on the exposed coating thin layer by electrolytic plating, and the mask pattern is removed. Subsequently, the unnecessary coating thin layer is removed by etching or the like, and a conductive layer having the desired wiring pattern is 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.

Semiconductor devices, for example, can be used as various semiconductor devices for electrical products (such as computers, mobile phones, digital cameras and televisions) and passenger vehicles (such as bicycles, cars, trains, ships and airplanes).

The semiconductor device of the present invention can be manufactured by installing parts (semiconductor chips) at the through-holes of a printed wiring board. "Through-holes" refer to "the places in the printed wiring board where electrical signals are transmitted", and the places can be the surface or buried in the substrate. In addition, the semiconductor chip is not particularly limited as long as it is an electrical circuit component made of semiconductors.

When manufacturing semiconductor devices, there is no particular limitation on the method of mounting semiconductor chips as long as the semiconductor chips can function effectively. Specifically, there are wire bonding mounting methods, flip chip mounting methods, bumpless stacking layer (BBUL) mounting methods, anisotropic conductive film (ACF) mounting methods, non-conductive film (NCF) mounting methods, etc. Among them, "bumpless stacking layer (BBUL) mounting method" means "a mounting method of directly embedding a semiconductor chip in a recess of a printed wiring board and then connecting the semiconductor chip to the wiring on the printed wiring board." [Example]

The present invention will be specifically described below with reference to the following embodiments. However, the present invention is not limited to the following embodiments. In the following description, "parts" and "%" representing "amount" are respectively "parts by mass" and "% by mass" unless otherwise specified. In addition, the operations described below are performed at room temperature and pressure unless otherwise specified.

[Measurement of the peel strength (adhesion strength) between the insulating layer and the conductive layer] <Production of samples for measurement and evaluation> (1) Treatment of the bottom layer of the inner circuit substrate A micro-etchant ("CZ8101" manufactured by Merck) was used to etch 1μm on both sides of a glass cloth-based epoxy resin laminate (copper foil thickness 18μm, substrate thickness 0.4mm, "R1515A" manufactured by Panasonic) with copper-plated surfaces on both sides forming the inner circuits to roughen the copper surface.

(2) Lamination of resin sheets The resin sheets prepared in the embodiment and comparative example were laminated on both sides of the inner circuit substrate using a batch vacuum pressure laminator ("MVLP-500" manufactured by Meiki Seisakusho Co., Ltd.) in such a way that the resin composition layer was bonded to the inner circuit substrate. The lamination method was to reduce the pressure to below 13hPa for 30 seconds, and then perform the lamination treatment at 100°C and a pressure of 0.74MPa for 30 seconds.

(3) Hardening of the resin composition layer The laminated resin sheet is heated at 100°C for 30 minutes and then at 170°C for 30 minutes to thermally harden the resin composition layer to form an insulating layer.

(4) Forming via holes using UV-YAG laser The support was peeled off to expose the surface of the insulating layer, and a UV-YAG laser processing machine ("LU-2L212/M50L" manufactured by VIA MECHANICS) was used to form via holes on the insulating layer under the following conditions. Conditions: output 0.30W, number of shots 25, target top diameter 30μm

(5) Dry slag removal treatment After forming the through hole, the inner circuit substrate with the insulating layer formed was treated for 5 minutes using a vacuum plasma etching device (100-E PLASMA SYSTEM manufactured by Tepla) under the conditions of O ₂ /CF ₄ (mixed gas ratio) = 25/75 and a vacuum degree of 100Pa.

(6) Formation of a conductor layer using a dry method A titanium layer (30 nm thick) was formed using a sputtering device (Canon Anelva's "E-400S"), followed by a copper layer (300 nm thick). The resulting substrate was subjected to a 30-minute annealing treatment at 150°C, and then an etching resist was formed using a semi-additive method. After a pattern was formed by exposure and development, copper sulfate electroplating was performed to form a 25 μm thick conductor layer. After the conductor pattern was formed, an annealing treatment was performed at 200°C for 60 minutes. The resulting printed wiring board is referred to as "evaluation substrate A."

<Determination of peel strength> The peel strength between the insulating layer and the conductive layer was measured by measuring the evaluation substrate A in accordance with JIS C6481. Specifically, a portion of 10 mm wide and 100 mm long was cut into the conductive layer of the evaluation substrate A, and one end was peeled off and clamped with a clamp. The load (kgf/cm) when 35 mm was pulled off at a speed of 50 mm/min in the vertical direction was measured at room temperature to obtain the peel strength. A tensile tester ("AC-50C-SL" manufactured by TSE) was used for the measurement.

[Determination of loss coefficient] <Production of samples for measurement and evaluation> The resin sheets prepared in the embodiment and comparative example were heated at 200°C for 90 minutes to thermally cure the resin component layer, and then the support was peeled off. The resulting cured product is referred to as "Evaluation cured product B".

<Determination of loss coefficient> The evaluation hardened material B was cut into test pieces with a width of 2 mm and a length of 80 mm. The loss coefficient of the test piece was measured at a frequency of 5.8 GHz and a temperature of 23°C using the "HP8362B" manufactured by Agilent Technologies using the common cavity resonance method. The measurement was performed on two test pieces and the average value was calculated.

[Evaluation of storage stability of resin coating] The resin coatings prepared in the examples and comparative examples were stored at 5°C for 100 hours. After returning to room temperature (25°C), the coagulation was visually confirmed and the storage stability of the resin coating was evaluated according to the following criteria. 0: No coagulation larger than 1 mm was observed. ×: Coagulation larger than 1 mm was observed.

[Example 1] 15 parts of bisphenol A epoxy resin ("828US" manufactured by Mitsubishi Chemical Corporation, epoxy equivalent of about 180) and 3 parts of styrene elastomer (hydrogenated styrene thermoplastic elastomer "Tuftec H1043" manufactured by Asahi Kasei Corporation, styrene content 67%) were added to 25 parts of toluene and 15 parts of MEK, and heated and dissolved while stirring. After cooling to room temperature, the mixture was mixed with 46 parts of a radical polymerizable compound (OPE-2St manufactured by Mitsubishi Gas Chemical Co., Ltd., number average molecular weight 1200, non-volatile component 65% by mass in toluene solution), 30 parts of a radical polymerizable compound (NK ester A-DOG manufactured by Shin-Nakamura Chemical Co., Ltd., molecular weight 326), 28 parts of an active ester type curing agent (EXB9416-70BK manufactured by DIC Corporation, non-volatile component 70% by mass in methyl isobutyl ketone solution with an active group equivalent of about 330), and 1,2-dimethoxy-1,4 ... A phenolic hardener (LA-3018-50P manufactured by DIC Corporation, a 50% solid solution of 2-methoxypropanol with a hydroxyl equivalent of about 151) 8 parts, a hardening accelerator (N,N-dimethyl-4-aminopyridine (DMAP), a 5% solid solution of MEK) 6 parts, a polymerization initiator (Percumyl P manufactured by NOF Corporation) 1 part, and 250 parts of spherical silica (average particle size 0.5 μm, specific surface area 5.9 m ² /g, SO-C2 manufactured by ADMATECHS Corporation) surface-treated with an anilinosilane coupling agent (KBM573 manufactured by Shin-Etsu Chemical Co., Ltd.) were mixed and uniformly dispersed using a high-speed rotary grinder to prepare a resin coating.

Next, a resin coating was evenly applied on the release surface of a release-treated polyethylene terephthalate film ("AL5" manufactured by Lind Company, thickness 38 μm) so that the thickness of the resin composition layer after drying was 20 μm, and then dried at 80 to 120°C (average 100°C) for 3 minutes to obtain a resin sheet.

[Example 2] 15 parts of a biphenyl epoxy resin ("NC3000L" manufactured by Nippon Kayaku Co., Ltd., epoxy equivalent of about 269) and 3 parts of a styrene-based elastomer ("Tuftec P2000", a hydrogenated styrene-based thermoplastic elastomer manufactured by Asahi Kasei Corporation, styrene content 67%) were added to 25 parts of toluene and 15 parts of MEK, and heated and dissolved while stirring. After cooling to room temperature, the mixture was mixed with 46 parts of a radical polymerizable compound (OPE-2St manufactured by Mitsubishi Gas Chemical Co., Ltd., number average molecular weight 1200, toluene solution with non-volatile components of 65% by mass), 30 parts of a radical polymerizable compound (NK ester A-DOG manufactured by Shin-Nakamura Chemical Co., Ltd., molecular weight 326), 30 parts of an active ester type curing agent (HPC8000-65T manufactured by DIC Corporation, toluene solution with solid components of 65% by mass), and 1,000 parts of a 3-hydroxy-1,1-diol-containing ester. 4 parts of phenolic hardener (LA-3018-50P manufactured by DIC Corporation, 50% solid content 2-methoxypropanol solution with hydroxyl equivalent of about 151), 8 parts of carbodiimide hardener (V-03 manufactured by Nisshinbo Chemical Co., Ltd., active group equivalent of about 216, 50% solid content toluene solution), 6 parts of hardening accelerator (N,N-dimethyl-4-aminopyridine (DMAP), 5% solid content MEK solution), 1 part of polymerization initiator (Perbutyl C manufactured by NOF Corporation), spherical silica (average particle size 0.5μm, specific surface area ^5.9m2 ) surface treated with an anilinosilane coupling agent (KBM573 manufactured by Shin-Etsu Chemical Co., Ltd.) /g, and 250 parts of "SO-C2" manufactured by ADMATECHS Co.), and uniformly dispersed using a high-speed rotary grinder to obtain a resin coating, and a resin sheet was obtained in the same manner as in Example 1.

[Example 3] 15 parts of biphenyl epoxy resin ("NC3000L" manufactured by Nippon Kayaku Co., Ltd., epoxy equivalent of about 269) and 3 parts of styrene elastomer (hydrogenated styrene thermoplastic elastomer "Tuftec P2000" manufactured by Asahi Kasei Corporation, styrene content 67%) were added to 25 parts of toluene and 15 parts of MEK, and heated and dissolved while stirring. After cooling to room temperature, it was mixed with 60 parts of a free radical polymerizable compound ("NK Ester A-DOG" manufactured by Shin-Nakamura Chemical Industry Co., Ltd., molecular weight 326) and a 3-hydroxy-1 ... 8 parts of phenolic hardener (LA-3018-50P manufactured by DIC Corporation, 50% solid content 2-methoxypropanol solution with a hydroxyl equivalent of about 151), 6 parts of hardening accelerator (N,N-dimethyl-4-aminopyridine (DMAP), 5% solid content MEK solution), 1 part of polymerization initiator (Perbutyl C manufactured by NOF Corporation), spherical silica (average particle size 0.5μm, specific surface area ^5.9m2 ) surface treated with an anilinosilane coupling agent (KBM573 manufactured by Shin-Etsu Chemical Co., Ltd.) /g, and 250 parts of "SO-C2" manufactured by ADMATECHS Co.), and uniformly dispersed using a high-speed rotary grinder to prepare a resin coating, and a resin sheet was prepared in the same manner as in Example 1.

[Example 4] 15 parts of a bisphenol AF type epoxy resin ("YL7760" manufactured by Mitsubishi Chemical Corporation, epoxy equivalent of about 238), 20 parts of a styrene-based elastomer ("Tuftec H1043" manufactured by Asahi Kasei Corporation, styrene content 67%), and 20 parts of another styrene-based elastomer ("Tuftec MP10" manufactured by Asahi Kasei Corporation, styrene content 30%) were added to 50 parts of toluene and 20 parts of MEK, and heated and dissolved while stirring. After cooling to room temperature, the mixture was mixed with 46 parts of a radical polymerizable compound (OPE-2St manufactured by Mitsubishi Gas Chemical Co., Ltd., number average molecular weight 1200, non-volatile component 65% by mass toluene solution), 30 parts of a radical polymerizable compound (NK ester A-DOG manufactured by Shin-Nakamura Chemical Co., Ltd., molecular weight 326), 16 parts of a carbodiimide-based curing agent (V-03 manufactured by Nisshinbo Chemical Co., Ltd., active group equivalent of about 216, toluene solution with a solid content of 50% by mass), 6 parts of a curing accelerator (N,N-dimethyl-4-aminopyridine (DMAP), a MEK solution with a solid content of 5% by mass), and 10 parts of a polymerization initiator (Perbutyl C") and 250 parts of spherical silica (average particle size 0.5 μm, specific surface area 5.9 ^m2 /g, "SO-C2" manufactured by ADMATECHS) surface-treated with an anilinosilane coupling agent (manufactured by Shin-Etsu Chemical Co., Ltd., "KBM573") were mixed and uniformly dispersed using a high-speed rotary grinder to prepare a resin coating. Otherwise, a resin sheet was prepared in the same manner as in Example 1.

[Example 5] 15 parts of bisphenol AF epoxy resin ("YL7760" manufactured by Mitsubishi Chemical Corporation, epoxy equivalent of about 238) and 40 parts of styrene elastomer (hydrogenated styrene thermoplastic elastomer "Tuftec H1043" manufactured by Asahi Kasei Corporation, styrene content 67%) were added to 50 parts of toluene and 20 parts of MEK, and heated and dissolved while stirring. After cooling to room temperature, it was mixed with 46 parts of a radical polymerizable compound ("OPE-2St" manufactured by Mitsubishi Gas Chemical Corporation, number average molecular weight 1200, toluene solution with non-volatile components of 65% by mass), 30 parts of a radical polymerizable compound ("NK Ester A-DOG" manufactured by Shin-Nakamura Chemical Industry Co., Ltd., molecular weight 326), and benzoxazoline. 16 parts of a curing agent (a 50% by weight solid solution of "ODA-BOZ" manufactured by JFE Chemical Co., Ltd. in MEK), 6 parts of a curing accelerator (a 5% by weight solid solution of N,N-dimethyl-4-aminopyridine (DMAP) in MEK), 1 part of a polymerization initiator (a 5% by weight solid solution of "Perbutyl C" manufactured by NOF Corporation), and 250 parts of spherical silica (average particle size 0.5 μm, specific surface area 5.9 m ² /g, "SO-C2" manufactured by ADMATECHS Co., Ltd.) surface-treated with an anilinosilane coupling agent (a 573 manufactured by Shin-Etsu Chemical Co., Ltd.) were mixed and uniformly dispersed using a high-speed rotary grinder to prepare a resin coating. Otherwise, a resin sheet was prepared in the same manner as in Example 1.

[Example 6] 15 parts of bisphenol AF epoxy resin ("YL7760" manufactured by Mitsubishi Chemical Corporation, epoxy equivalent of about 238) and 3 parts of styrene elastomer (hydrogenated styrene thermoplastic elastomer "Tuftec H1043" manufactured by Asahi Kasei Corporation, styrene content 67%) were added to 25 parts of toluene and 15 parts of MEK, and heated and dissolved while stirring. After cooling to room temperature, the mixture was mixed with 92 parts of a radical polymerizable compound (OPE-2St manufactured by Mitsubishi Gas Chemical Co., Ltd., number average molecular weight 1200, non-volatile component 65% by mass in toluene solution), 30 parts of a radical polymerizable compound (NK ester A-DOG manufactured by Shin-Nakamura Chemical Co., Ltd., molecular weight 326), an active ester type curing agent (DIC Corporation "HPC8000-65T", solid content 6 30 parts of carbodiimide curing agent (V-03 manufactured by Nisshinbo Chemical Co., Ltd., active group equivalent of about 216, 50% by weight toluene solution), 16 parts of curing accelerator (N,N-dimethyl-4-aminopyridine (DMAP), 5% by weight MEK solution), 6 parts of polymerization initiator (Perbutyl C") and 200 parts of spherical silica (average particle size 0.3 μm, specific surface area 30.7 ^m2 /g, "UFP-30" manufactured by DENKA Corporation) surface-treated with an anilinosilane coupling agent (manufactured by Shin-Etsu Chemical Co., Ltd., "KBM573") were mixed and uniformly dispersed using a high-speed rotary grinder to prepare a resin coating. Otherwise, a resin sheet was prepared in the same manner as in Example 1.

[Example 7] 5 parts of a biphenyl type epoxy resin ("NC3000L" manufactured by Nippon Kayaku Co., Ltd., epoxy equivalent of about 269), 10 parts of a bisphenol AF type epoxy resin ("YL7760" manufactured by Mitsubishi Chemical Corporation, epoxy equivalent of about 238), 20 parts of a styrene type elastomer ("Tuftec P2000" hydrogenated styrene type thermoplastic elastomer manufactured by Asahi Kasei Corporation, styrene content 67%), and 20 parts of a styrene type elastomer other than component (C) ("Epogrined AT501" epoxy styrene-butadiene thermoplastic elastomer manufactured by Daicel Corporation, styrene content 40%) were added to 50 parts of toluene and 20 parts of MEK, and the mixture was heated and dissolved while stirring. After cooling to room temperature, the mixture was mixed with 90 parts of a radical polymerizable compound ("NK Ester A-DOG" manufactured by Shin-Nakamura Chemical Industry Co., Ltd., molecular weight 326), 30 parts of an active ester type curing agent ("HPC8000-65T" manufactured by DIC Corporation, toluene solution with a solid content of 65% by mass), and 1,2-dimethoxy- ... 4 parts of phenolic hardener (LA-3018-50P manufactured by DIC Corporation, 50% solid content 2-methoxypropanol solution with hydroxyl equivalent of about 151), 8 parts of carbodiimide hardener (V-03 manufactured by Nisshinbo Chemical Co., Ltd., active group equivalent of about 216, 50% solid content toluene solution), 6 parts of hardening accelerator (N,N-dimethyl-4-aminopyridine (DMAP), 5% solid content MEK solution), 1 part of polymerization initiator (Perbutyl C manufactured by NOF Corporation), spherical silica (average particle size 0.3μm, specific surface area ^30.7m2 ) surface treated with an anilinosilane coupling agent (KBM573 manufactured by Shin-Etsu Chemical Co., Ltd.) /g, and 200 parts of "UFP-30" manufactured by DENKA Corporation) were mixed and uniformly dispersed using a high-speed rotary grinder to prepare a resin coating. Otherwise, a resin sheet was prepared in the same manner as in Example 1.

[Comparative Example 1] In Example 1, 3 parts of styrene-based elastomer (hydrogenated styrene-based thermoplastic elastomer "Tuftec H1043" manufactured by Asahi Kasei Corporation, styrene content 67%) are not used. Except for the above matters, the resin coating and resin sheet are prepared in the same manner as in Example 1.

[Comparative Example 2] In Example 1, 1) 3 parts of styrene-based elastomer (hydrogenated styrene-based thermoplastic elastomer "Tuftec H1043" manufactured by Asahi Kasei Corporation, styrene content 67%) were not used, 2) 28 parts of active ester type hardener ("EXB9416-70BK" manufactured by DIC Corporation, methyl isobutyl ketone solution with an active group equivalent of about 330 and a non-volatile component content of 70% by mass) were not used, and 3) the three 8 parts of the phenolic hardener (LA-3018-50P manufactured by DIC Corporation, 50% solid content 2-methoxypropanol solution with a hydroxyl equivalent of about 151) of the skeleton were replaced with 16 parts of the carbodiimide hardener (V-03 manufactured by Nisshinbo Chemical Co., Ltd., active group equivalent of about 216, 50% solid content toluene solution) 4) 1 part of the polymerization initiator (Percumyl P manufactured by NOF Corporation) was replaced with 1 part of the polymerization initiator (Perbutyl C manufactured by NOF Corporation). Except for the above matters, the resin coating was prepared in the same manner as in Example 1. The resin coating was used to prepare resin sheets in the same manner as in Example 1. However, after dispersion using a high-speed rotary grinder, more than 10 agglomerates larger than 1 mm were visually observed, so the preparation of the resin sheets was discontinued.

[Comparative Example 3] In Example 6, 3 parts of styrene-based elastomer (hydrogenated styrene-based thermoplastic elastomer "Tuftec H1043" manufactured by Asahi Kasei Corporation, styrene content 67%) are not used. Except for the above matters, the resin coating and resin sheet are prepared in the same manner as in Example 6.

In Examples 1 to 7, it was confirmed that even when the components (E) to (H) were not contained, the same results as those of the above-mentioned Examples were obtained, although there were slight differences.

Claims (13)

A resin composition comprising: (A) epoxy resin, (B) a curing agent selected from phenolic curing agents, active ester curing agents, carbodiimide curing agents and benzoxazoline

(C) a styrene-based elastomer, and (D) a resin having a free radical polymerizable unsaturated group; the content of styrene units in the component (C) is 61% by mass or more when the component (C) is 100% by mass, the content of the component (A) is 1% by mass or more and 15% by mass or less when the non-volatile components in the resin composition are 100% by mass, the content of the component (B) is 0.1% by mass or more and 20% by mass or less when the non-volatile components in the resin composition are 100% by mass, and the content of the component (C) is 61% by mass or more when the component (C) is 100% by mass. ) content, when the non-volatile components in the resin composition are taken as 100 mass%, is 0.5 mass% or more and 18 mass% or less, the content of the component (D) is 5 mass% or more and 50 mass% or less, when the non-volatile components in the resin composition are taken as 100 mass%, the content of the component (C) when the non-volatile components in the resin composition are taken as 100 mass% is denoted as C1, and the content of the component (B) when the non-volatile components in the resin composition are taken as B1, C1/B1 is 0.01 or more and 10 or less. The resin composition of claim 1, wherein the component (D) contains at least one selected from vinylphenyl, acryl, and methacryl. The resin composition of claim 1, wherein the number average molecular weight of component (D) is less than 3000. The resin composition of claim 1 further contains (E) inorganic filler. In the resin composition of claim 4, the content of component (E) is 50% by mass or more when the non-volatile components in the resin composition are set to 100% by mass. 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 for the purpose of forming a conductive layer. The resin composition of claim 1 is used to form an insulating layer for the purpose of forming a conductive layer by sputtering or metal foil. The resin composition of claim 1 is used as an insulating layer for forming a through hole having a top diameter of 45 μm or less. The resin composition of claim 1 is used to form an insulating layer with a thickness of less than 20 μm. A resin sheet characterized by comprising: a support body, and a resin composition layer disposed on the support body and comprising a resin composition of any one of claims 1 to 10. A printed wiring board characterized by comprising: an insulating layer formed by a cured product of the resin composition of any one of claims 1 to 10. A semiconductor device characterized by comprising: a printed wiring board as claimed in claim 12.