TWI875692B - Resin composition, sheet laminate, printed wiring board and semiconductor device - Google Patents

Abstract

The subject of the present invention is to provide a resin composition with low dielectric tangent and good coating adhesion and substrate adhesion. The solution of the present invention is a resin composition, which includes (A) epoxy resin, (B) hardener, (C) resin with free radical polymerizable unsaturated groups and (D) aliphatic phosphine compound.

Description

Resin composition, sheet laminate material, printed wiring board and semiconductor device

The present invention relates to a resin composition and further to a sheet-like laminate material, a printed wiring board and a semiconductor device using the resin composition.

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

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

[Problems to be solved by the invention]

In recent years, the demand for resin compositions that can form insulating layers with low dielectric tangent has been increasing. In addition, the miniaturization and high performance of electronic devices have progressed, and the multi-layer stacking of printed wiring boards has sought to miniaturize and increase the density of wiring.

In order to achieve further miniaturization and high density of wiring, resin compositions with low dielectric tangent and good coating adhesion and substrate adhesion are sought, but all of these have not yet been fully satisfied.

The subject of the present invention is to provide a resin composition with low dielectric tangent and good coating adhesion and substrate adhesion. [Means for solving the subject]

As a result of diligent research on the above-mentioned problems, the inventors of the present invention have found that the above-mentioned problems can be solved by combining (C) a resin having a free radical polymerizable unsaturated group and (D) an aliphatic phosphine compound and blending them into a resin composition comprising (A) an epoxy resin and (B) a hardener, 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 curing agent, (C) a resin having a free radical polymerizable unsaturated group, and (D) an aliphatic phosphine compound. [2] The resin composition as described in [1], wherein the component (D) has a phosphorus atom directly bonded to an aliphatic carbon atom. [3] The resin composition as described in [1] or [2], wherein the component (D) has 1 to 4 phosphorus atoms directly bonded to an aliphatic carbon atom in one molecule. [4] The resin composition as described in any one of [1] to [3], wherein the component (D) has 2 to 40 aliphatic carbon atoms in one molecule. [5] The resin composition according to any one of [1] to [4], wherein the component (D) is a compound represented by formula (D1) or formula (D2), (In the formula, ^Rd1 and ^Rd2 each independently represent a hydrogen atom or a monovalent group represented by the formula: -(RO) _l -R', wherein l represents an integer of 0 to 5, R represents a divalent aromatic group which may have a substituent, or a divalent aliphatic group which may have a substituent, R' represents a monovalent aromatic group which may have a substituent, or a monovalent aliphatic group which may have a substituent, and when R' exists in plural, they may be the same as or different from each other, ^Rd3 represents a monovalent group represented by the formula: -(R''-O) _m -R''', wherein m represents an integer of 0 to 5, R'' represents a divalent aliphatic group which may have a substituent, R''' represents a monovalent aliphatic group which may have a substituent, and when R'' exists in plural, they may be the same as or different from each other) (wherein, ^Rd1 and ^Rd2 have the same meanings as above, L represents a divalent group represented by the formula: -(R''-O) _n -R''-, wherein n represents an integer from 0 to 5, R'' has the same meaning as above, and when R'' is present in plural numbers, they may be the same as or different from each other, ^Rd4 and ^Rd5 each independently represent a hydrogen atom, a monovalent group represented by the formula: -(RO) _l -R', or a monovalent group represented by the formula: -LP( ^-Rd1 )(- ^Rd2 ), wherein l, R, R', L, ^Rd1 and ^Rd2 have the same meanings as above). [6] The resin composition as described in any one of [1] to [5], wherein the component (D) comprises a compound represented by any one of the following formulas, [7] A resin composition as described in any one of [1] to [6], wherein the content of component (D) is 0.001% by mass to 10% by mass, when the resin component is taken as 100% by mass. [8] A resin composition as described in any one of [1] to [7], wherein component (A) comprises a biphenyl epoxy resin. [9] A resin composition as described in any one of [1] to [8], wherein component (B) comprises an active ester hardener. [10] A resin composition as described in any one of [1] to [9], wherein component (C) comprises a carbon-carbon double bond. [11] The resin composition as described in any one of [1] to [10], wherein the component (C) has one or more groups selected from the group consisting of an acryl group, a methacryl group, a styryl group, an allyl group, a vinyl group, a propenyl group and a maleimide group. [12] The resin composition as described in any one of [1] to [11], further comprising (E) an inorganic filler. [13] The resin composition as described in [12], wherein the content of the (E) inorganic filler is 50% by mass or more when the non-volatile components in the resin composition are taken as 100% by mass. [14] The resin composition as described in any one of [1] to [13], which is used to form an insulating layer of a conductive layer. [15] A sheet-like laminate material comprising a resin composition as described in any one of [1] to [14]. [16] A printed wiring board comprising an insulating layer formed of a cured product of the resin composition as described in any one of [1] to [14]. [17] A semiconductor device comprising a cured product of the resin composition as described in any one of [1] to [14]. [Effect of the invention]

According to the present invention, a resin composition having low dielectric tangent and good coating adhesion and substrate adhesion can be provided.

<Explanation of terms> In this specification, the term "aliphatic phosphine compound" means a compound in which at least one of the organic groups bonded to a phosphorus atom among organic phosphine compounds is an aliphatic group. In this specification, the term "aliphatic group" broadly means a non-aromatic organic group, including (i) non-aromatic hydrocarbon groups and (ii) non-aromatic organic groups containing impurities such as oxygen atoms, nitrogen atoms, sulfur atoms, boron atoms and silicon atoms. When the aliphatic group is a non-aromatic organic group containing impurities, the carbon atom of the organic group is bonded to a phosphorus atom. Accordingly, the "aliphatic phosphine compound" of the present invention is characterized by containing a phosphorus atom directly bonded to an aliphatic carbon atom.

In the present specification, the term "optionally having a substituent" appended to the front of a group means both the case where the hydrogen atoms of the group are not substituted by a substituent and the case where a part or all of the hydrogen atoms of the group are substituted by a substituent.

In the present specification, the term "substituent" means, unless otherwise specified, a halogen atom, an alkyl group, a cycloalkyl group, an alkoxy group, a cycloalkoxy group, an aryl group, an aryloxy group, an arylalkyl group, an arylalkoxy group, a monovalent heterocyclic group, an alkylene group, an amino group, a silyl group, a phosphino group, a hydroxyl group, a formyl group, an acyl group, an acyloxy group, a carboxyl group, a cyano group, a nitro group, a hydroxyl group, and a pendoxy group.

As the halogen atom used as a substituent, for example, there can be listed a fluorine atom, a chlorine atom, a bromine atom and an iodine atom. The alkyl group used as a substituent may be either linear or branched. The number of carbon atoms of the alkyl group is preferably 1 to 12, more preferably 1 to 6, and even more preferably 1 to 3. The number of carbon atoms of the cycloalkyl group used as a substituent is preferably 3 to 12, more preferably 3 to 6. The alkoxy group used as a substituent may be either linear or branched. The number of carbon atoms of the alkoxy group is preferably 1 to 12, more preferably 1 to 6. The number of carbon atoms of the cycloalkoxy group used as a substituent is preferably 3 to 12, more preferably 3 to 6. The number of carbon atoms of the aryl group used as a substituent is preferably 6 to 14, more preferably 6 to 10. The number of carbon atoms of the aryloxy group used as a substituent is preferably 6 to 14, more preferably 6 to 10. The number of carbon atoms of the arylalkyl group used as a substituent is preferably 7 to 15, more preferably 7 to 11. The number of carbon atoms of the arylalkoxy group used as a substituent is preferably 7 to 15, more preferably 7 to 11. The monovalent heterocyclic group used as a substituent refers to a group in which one hydrogen atom is removed from the heterocyclic ring of the heterocyclic compound. The number of carbon atoms of the monovalent heterocyclic group is preferably 3 to 15, more preferably 3 to 9. The monovalent heterocyclic group also includes a monovalent aromatic heterocyclic group (heteroaryl group). The alkylene group used as a substituent refers to a group in which two hydrogen atoms are removed from the same carbon atom of an alkane. The number of carbon atoms of the alkylene group is preferably 1 to 12, more preferably 1 to 6, and particularly preferably 1 to 3. The amino group, silyl group, phosphino group, and alkyl group used as a substituent are groups represented by the formula: _-NH2 , _-SiH3 , _-PH2 , and -SH, respectively. The acyl group used as a substituent is a group represented by the formula: -C(=O) ^-RS (wherein ^RS is an alkyl group or an aryl group). The alkyl group represented by ^RS may be either linear or branched. The number of carbon atoms of the acyl group is preferably 2 to 13, and more preferably 2 to 7. The acyloxy group used as a substituent is a group represented by the formula: -OC(=O) ^-RS (wherein ^RS has the same meaning as above). The number of carbon atoms of the acyloxy group is preferably 2 to 13, more preferably 2 to 7. The above-mentioned substituents may further have substituents (in the case of "secondary substituents"). As secondary substituents, the same substituents as those mentioned above can be used unless otherwise specified. As substituents having secondary substituents, for example, dimethylamino can be listed.

The present invention is described in detail below according to the appropriate implementation mode.

[Resin composition] The resin composition of the present invention is characterized by comprising (A) epoxy resin, (B) hardener, (C) resin having free radical polymerizable unsaturated groups and (D) aliphatic phosphine compound.

The resin composition of the present invention, which is blended with (A) an epoxy resin and (B) a curing agent, (C) a resin having a free radical polymerizable unsaturated group and (D) an aliphatic phosphine compound, can provide a cured product having a low dielectric tangent and good coating adhesion (adhesion to a coated conductive layer) and substrate adhesion (adhesion to a substrate conductive layer).

<(A) Epoxy resin> The resin composition of the present invention includes an epoxy resin as component (A). Examples of the epoxy resin include bisphenol epoxy resins, dicyclopentadiene epoxy resins, trisphenol epoxy resins, naphthol novolac epoxy resins, phenol novolac epoxy resins, tert-butyl-ophthalic acid diol epoxy resins, naphthalene epoxy resins, naphthol epoxy resins, anthracene epoxy resins, glycidylamine epoxy resins, and glycidyl ester epoxy resins. Epoxy resins include 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, epoxy resins containing spiro rings, oxalic acid type epoxy resins, oxalic acid dimethanol type epoxy resins, naphthyl ether type epoxy resins, trihydroxymethyl type epoxy resins, and tetraphenylethane type epoxy resins. The epoxy resins may be used alone or in combination of two or more. Bisphenol type epoxy resin refers to epoxy resin having a bisphenol structure, for example, bisphenol A type epoxy resin, bisphenol F type epoxy resin, bisphenol S type epoxy resin, bisphenol AF type epoxy resin. Biphenyl type epoxy resin refers to epoxy resin having a biphenyl structure, where the biphenyl structure may have a substituent such as an alkyl group, an alkoxy group, an aryl group, etc. Accordingly, bis(dimethylphenol) type epoxy resin and biphenyl aralkyl type epoxy resin also include biphenyl type epoxy resin.

As the epoxy resin, an aromatic epoxy resin is preferred. Here, the aromatic epoxy resin refers to an epoxy resin having an aromatic ring in its molecule. The aromatic ring includes not only a monocyclic structure such as a benzene ring, but also a polycyclic aromatic structure such as a naphthalene ring and an aromatic heterocyclic structure. Among them, from the viewpoint of achieving excellent coating adhesion and substrate adhesion in the combination of component (C) and component (D), component (A) is preferably one or more selected from the group consisting of bisphenol type epoxy resin, biphenyl type epoxy resin, naphthyl ether type epoxy resin, naphthalene type tetrafunctional epoxy resin and naphthol type epoxy resin, more preferably one or more selected from the group consisting of bisphenol type epoxy resin and biphenyl type epoxy resin, and even more preferably biphenyl type epoxy resin. In a suitable embodiment, component (A) includes biphenyl type epoxy resin.

The epoxy resin preferably has two or more epoxy groups in one molecule. When the nonvolatile component of the epoxy resin is taken as 100 mass %, the ratio of the epoxy resin having two or more epoxy groups in one molecule is preferably 50 mass % or more, more preferably 60 mass % or more, and even more preferably 70 mass % or more.

Epoxy resins include epoxy resins that are liquid at 20°C (hereinafter referred to as "liquid epoxy resins") and epoxy resins that are solid at 20°C (hereinafter referred to as "solid epoxy resins"). The resin composition of the present invention may contain a liquid epoxy resin alone or a solid epoxy resin alone as component (A), or may contain a combination of a liquid epoxy resin and a solid epoxy resin. The resin composition of the present invention as component (A) preferably comprises a solid epoxy resin, preferably a solid epoxy resin alone, or a combination of a solid epoxy resin and a liquid 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.

As the solid epoxy resin, biphenyl type epoxy resin, naphthalene type epoxy resin, naphthalene type tetrafunctional epoxy resin, cresol novolac type epoxy resin, dicyclopentadiene type epoxy resin, trisphenol type epoxy resin, naphthol type epoxy resin, biphenyl type epoxy resin, naphthyl ether type epoxy resin are preferred. , anthracene type epoxy resins, bisphenol type epoxy resins, tetraphenylethane type epoxy resins, more preferably bis(xylenol) type epoxy resins, biphenyl aralkyl type epoxy resins, naphthyl ether type epoxy resins, naphthalene type tetrafunctional epoxy resins and naphthol type epoxy resins, and even more preferably bis(xylenol) type epoxy resins.

Specific examples of solid epoxy resins include "HP4032H" (naphthalene-based epoxy resin) manufactured by DIC Corporation; "HP-4700" and "HP-4710" (naphthalene-based tetrafunctional epoxy resin) manufactured by DIC Corporation; "N-690" (cresol-phenolic epoxy resin) manufactured by DIC Corporation; "N-695" (cresol-phenolic epoxy resin) manufactured by DIC Corporation; "HP-7200" (dicyclopentadiene-based epoxy resin) manufactured by DIC Corporation; and "HP-7 200HH", "HP-7200H", "EXA-7311", "EXA-7311-G3", "EXA-7311-G4", "EXA-7311-G4S", "HP6000" (naphthyl ether type epoxy resin); "EPPN-502H" (trisphenol type epoxy resin) manufactured by Nippon Kayaku Co., Ltd.; "NC7000L" (naphthol phenolic type epoxy resin) manufactured by Nippon Kayaku Co., Ltd.; "NC3000H", "NC3000" manufactured by Nippon Kayaku Co., Ltd. , "NC3000L", "NC3100" (biphenyl aralkyl type epoxy resin); "ESN475V" (naphthol type epoxy resin) manufactured by Nippon Steel Sumitomo Chemical Co., Ltd.; "ESN485" (naphthol phenolic type epoxy resin) manufactured by Nippon Steel Sumitomo Chemical Co., Ltd.; "YX4000H", "YX4000", "YL6121" (biphenyl type epoxy resin) manufactured by Mitsubishi Chemical Corporation; "YX4000HK" (bis(xylenol) type epoxy resin) manufactured by Mitsubishi Chemical Corporation; "YX8800" (onion type epoxy resin) manufactured by Osaka Gas Chemical Co., Ltd.; "PG-100" and "CG-500" (bisphenol AF type epoxy resin) manufactured by Mitsubishi Chemical Co., Ltd.; "YL7760" (bisphenol AF type epoxy resin) manufactured by Mitsubishi Chemical Co., Ltd.; "YL7800" (fluorene type epoxy resin) manufactured by Mitsubishi Chemical Co., Ltd.; "jER1010" (solid bisphenol A type epoxy resin) manufactured by Mitsubishi Chemical Co., Ltd.; "jER1031S" (tetraphenylethane type epoxy resin) manufactured by Mitsubishi Chemical Co., Ltd. These can be used alone or in combination of two or more.

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

As the liquid epoxy resin, bisphenol type epoxy resin, naphthalene type epoxy resin, epoxy propyl ester type epoxy resin, epoxy propyl amine type epoxy resin, phenol novolac type epoxy resin, aliphatic epoxy resin having an ester skeleton, cyclohexane type epoxy resin, cyclohexanedimethanol type epoxy resin are preferred. The preferred epoxy resins are epoxy resins of the type bisphenol A, epoxy resins of the type bisphenol F, epoxy resins of the type bisphenol AF and epoxy resins of the type naphthalene. The preferred epoxy resins are epoxy resins of the type bisphenol A, epoxy resins of the type bisphenol F, epoxy resins of the type bisphenol AF and epoxy resins of the type naphthalene. The preferred epoxy resins are epoxy resins of the type bisphenol A.

Specific examples of liquid epoxy resins include "HP4032", "HP4032D", and "HP4032SS" (naphthalene-based epoxy resins) manufactured by DIC Corporation; "828US", "jER828US", "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" (epoxypropylamine 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; Nagase "EX-721" manufactured by ChemteX (epoxypropyl ester type epoxy resin); "Celloxide 2021P" manufactured by Daicel (lipidic epoxy resin with ester skeleton); "PB-3600" manufactured by Daicel (epoxy resin with butadiene structure); "ZX1658" and "ZX1658GS" manufactured by Nippon Steel & Sumitomo Metal Chemicals (liquid 1,4-epoxypropyl cyclohexane type epoxy resin); etc. These can be used alone or in combination of two or more.

When a liquid epoxy resin and a solid epoxy resin are used in combination as epoxy resin, the mass ratio (liquid epoxy resin: solid epoxy resin) is preferably 1:0.1 to 1:15, more preferably 1:0.5 to 1:10, and particularly preferably 1:1 to 1:8. When the mass ratio of the liquid epoxy resin to the solid epoxy resin is within the above range, the following effects are achieved: i) when used in the form of a sheet-like laminated material, it has moderate adhesion; ii) when used in the form of a sheet-like laminated material, it has sufficient flexibility and improved workability; and iii) an insulating layer with sufficient breaking strength can be obtained.

The epoxy equivalent of the epoxy resin is preferably 50 to 5000, more preferably 50 to 3000, further preferably 80 to 2000, and particularly preferably 110 to 1000. When the epoxy equivalent of the epoxy resin is within the above range, the crosslinking density of the cured product of the resin composition becomes sufficient and the insulating layer with small surface roughness can be obtained. In addition, the epoxy equivalent is the mass of the resin including 1 equivalent of epoxy groups, and can be measured according to JIS K7236.

The weight average molecular weight of the epoxy resin is preferably 100 to 5000, more preferably 250 to 3000, and even more preferably 400 to 1500. The weight average molecular weight of a resin such as an epoxy resin is a weight average molecular weight in terms of polystyrene measured by gel permeation chromatography (GPC).

The content of the component (A) in the resin composition is preferably 3% by mass or more, more preferably 5% by mass or more, and even more preferably 8% by mass or more from the viewpoint of obtaining a cured product showing good mechanical strength and insulation reliability. The upper limit of the content of the component (A) is not particularly limited as long as the effect of the present invention can be exerted, but is preferably 70% by mass or less, more preferably 50% by mass or less, and even more preferably 30% by mass or less or 20% by mass or less.

In the present invention, the content of each component constituting the resin composition is a value when the total of non-volatile components in the resin composition is set to 100 mass %.

<(B) Hardener> The resin composition of the present invention includes a hardener as component (B). The hardener is not particularly limited as long as it has the function of hardening epoxy resin, and examples thereof include phenol hardeners, naphthol hardeners, active ester hardeners, benzoxazine hardeners, cyanate hardeners, and carbodiimide hardeners. The hardener may be used alone or in combination of two or more.

As the phenolic hardener and the naphthol hardener, from the viewpoint of heat resistance and water resistance, a phenolic hardener having a phenolic structure or a naphthol hardener having a phenolic structure is preferred. From the viewpoint of adhesion strength (peeling strength) with the conductive layer, a nitrogen-containing phenolic hardener or a nitrogen-containing naphthol hardener is preferred, and a phenolic hardener containing a triazine skeleton or a naphthol hardener containing a triazine skeleton is more preferred. Among them, from the viewpoint of highly satisfying heat resistance, water resistance and adhesion strength with the conductive layer, a phenolic novolac resin containing a triazine skeleton is preferred. Specific examples of the phenolic hardener and the naphthol hardener include "MEH-7700", "MEH-7810", and "MEH-7851" manufactured by Wagaku Co., Ltd., "NHN", "CBN", and "GPH" manufactured by Nippon Kayaku Co., Ltd., "SN-170", "SN-180", "SN-190", "SN-475", "SN-485", "SN-495", "SN-375", and "SN-395" manufactured by Nippon Steel & Sumitomo Chemical Co., Ltd., and "LA-7052", "LA-7054", "LA-3018", "LA-1356", and "TD2090" manufactured by DIC Co., Ltd.

As the active ester curing agent, there is no particular limitation, but generally, it is preferred to use a compound having two or more highly reactive ester groups such as phenol esters, thiophenol esters, N-hydroxylamine esters, esters of heterocyclic hydroxyl compounds, etc. in one molecule. The active ester curing agent is preferably obtained by a condensation reaction of a carboxylic acid compound and/or a thiocarboxylic acid compound with a hydroxyl compound and/or a thiol compound. In particular, from the viewpoint of improving heat resistance, an active ester curing agent obtained from a carboxylic acid compound and a hydroxyl compound is preferred, and an active ester curing agent obtained from a carboxylic acid compound and a phenol compound and/or a naphthol compound is more preferred. Examples of the carboxylic acid compound include benzoic acid, acetic acid, succinic acid, maleic acid, itaconic acid, phthalic acid, isophthalic acid, terephthalic acid, and pyromellitic acid. Examples of the phenol compound or naphthol compound include hydroquinone, resorcinol, bisphenol A, bisphenol F, bisphenol S, phenolphthalein, methylated bisphenol A, methylated bisphenol F, methylated bisphenol S, phenol, o-cresol, m-cresol, p-cresol, o-cresol, α-naphthol, β-naphthol, 1,5-dihydroxynaphthalene, 1,6-dihydroxynaphthalene, 2,6-dihydroxynaphthalene, dihydroxybenzophenone, trihydroxybenzophenone, tetrahydroxybenzophenone, phloroglucinol, benzenetriol, dicyclopentadiene-type diphenol compounds, and phenol novolac. Here, the so-called "dicyclopentadiene-type diphenol compound" refers to a diphenol compound obtained by condensing one molecule of dicyclopentadiene with two molecules of phenol.

Specifically, preferred are active ester compounds containing a dicyclopentadiene diphenol structure, active ester compounds containing a naphthalene structure, active ester compounds containing acetylated phenolic novolacs, and active ester compounds containing benzoylated phenolic novolacs. Among them, more preferred are active ester compounds containing a naphthalene structure and active ester compounds containing a dicyclopentadiene diphenol structure. The so-called "dicyclopentadiene diphenol structure" refers to a divalent structural unit composed of phenylene-dicyclopentadiene-phenylene.

As commercially available products of active ester-based hardeners, as active ester compounds containing a dicyclopentadiene-type diphenol structure, there are "EXB9451", "EXB9460", "EXB9460S", and "HPC-8000-65T" (manufactured by DIC Co., Ltd.), as active ester compounds containing a naphthalene structure, there is "EXB9416-70BK" (manufactured by DIC Co., Ltd.), as active ester compounds containing acetylated phenol novolacs, there is "DC808" (manufactured by Mitsubishi Chemical Co., Ltd.), as active ester compounds containing benzoylated phenol novolacs, there is "YLH1026" (manufactured by Mitsubishi Chemical Co., Ltd.), and the like.

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

Examples of the cyanate curing agent include bifunctional cyanate resins derived from bisphenol A dicyanate, polyphenol cyanate (oligo(3-methylene-1,5-phenylene cyanate)), 4,4'-methylenebis(2,6-dimethylphenylcyanate), 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-(methylethylene))benzene, bis(4-cyanatephenyl)sulfide and bis(4-cyanatephenyl)ether, polyfunctional cyanate resins such as phenol novolac and cresol novolac, and prepolymers of these cyanate resins partially triazinized. Specific examples of cyanate-based curing agents include "PT30" and "PT60" manufactured by Lonza Japan (both are phenolic novolac type multifunctional cyanate resins), "BA230" (a prepolymer of a trimer in which a portion or all of bisphenol A dicyanate is triazine-modified), and the like.

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

From the viewpoint of obtaining a cured product having excellent heat resistance and achieving good coating adhesion and substrate adhesion in the combination of the components (C) and (D), the component (B) preferably contains an active ester curing agent.

The amount ratio of (A) epoxy resin to (B) hardener is preferably in the range of 1:0.2 to 1:2, more preferably 1:0.3 to 1:1.5, and even more preferably 1:0.4 to 1:1.2, in the ratio of [total number of epoxy groups of epoxy resin]:[total number of reactive groups of hardener]. Here, the reactive groups of hardener are active hydroxyl groups, active ester groups, etc., which vary depending on the type of hardener. In addition, the total number of epoxy groups of epoxy resin is the total value obtained by dividing the solid content mass of each epoxy resin by the value of epoxy equivalent for all epoxy resins. The total number of reactive groups in the hardener is the total value obtained by dividing the solid component mass of each hardener by the reactive group equivalent value. By setting the ratio of epoxy resin to hardener within this range, the heat resistance of the resulting insulating layer can be further improved.

<(C) Resin having free radical polymerizable unsaturated groups> The resin composition of the present invention includes a resin having free radical polymerizable unsaturated groups (also called ethylene or acetylenic unsaturated groups) as component (C). In the following description, the "resin having free radical polymerizable unsaturated groups" as component (C) may be referred to as "unsaturated resin". The free radical polymerizable carbon-carbon unsaturated bond (ethylene or acetylenic unsaturated bond) may be included in not only one but also multiple carbon-carbon unsaturated bonds (ethylene or acetylenic unsaturated bonds) in one molecule of the unsaturated resin (C). The cured product of the resin composition containing the (C) unsaturated resin generally contains a molecular structure site formed by the reaction of the unsaturated bond site of the (C) unsaturated resin. As a result, the polarity of the cured product is reduced, and the value of the dielectric tangent can be reduced. The (C) component can be used alone or in combination of two or more.

(C) The free radical polymerizable unsaturated group possessed by the unsaturated resin is preferably an ethylenic unsaturated group having a carbon-carbon double bond. Accordingly, in one embodiment, the component (C) has a carbon-carbon double bond. In a more suitable embodiment, the free radical polymerizable unsaturated group is preferably one or more groups selected from the group consisting of an acryl group, a methacryl group, a styrene group, an olefinic group, and a maleimide group. As preferred examples of olefinic groups, allyl, vinyl, and propenyl can be cited. Therefore, in a suitable embodiment, the component (C) has one or more groups selected from the group consisting of an acryl group, a methacryl group, a styrene group, an allyl group, a vinyl, a propenyl group, and a maleimide group.

(C) The unsaturated resin is preferably a resin having a cyclic ether structure with 5 or more ring members (hereinafter also referred to as an "unsaturated resin containing a cyclic ether structure"). An unsaturated resin containing a cyclic ether structure can effectively reduce the dielectric tangent because the molecular motion is generally restricted.

The unsaturated resin containing a cyclic ether structure may contain only one cyclic ether structure or may contain a plurality of cyclic ether structures.

The cyclic ether structure may have a monocyclic structure including only one ring, a polycyclic structure including two or more rings, or a fused ring structure including fused rings.

The number of oxygen atoms contained in one cyclic ether structure is preferably 1 or more, more preferably 2 or more, preferably 5 or less, more preferably 4 or less, and even more preferably 3 or less, from the viewpoint of remarkably obtaining the desired effect of the present invention.

The cyclic ether structure is preferably 5-10-membered, more preferably 5-8-membered, and even more preferably 5-6-membered. Specific examples of the cyclic ether structure having 5 or more members include a furan structure, a tetrahydrofuran structure, a dioxolane structure, a pyran structure, a dihydropyran structure, a tetrahydropyran structure, and a dioxane structure. Among them, from the perspective of improving the compatibility of the resin composition, a dioxane structure is preferred. The dioxane structure includes a 1,2-dioxane structure, a 1,3-dioxane structure, and a 1,4-dioxane structure, and a 1,3-dioxane structure is preferred.

The cyclic ether structure may have a substituent. The type of the substituent is not particularly limited, and may be any of the substituents described above, such as alkyl and alkoxy. The number of carbon atoms of the substituent is as described above, but preferably 1 to 6, more preferably 1 to 3.

Among the unsaturated resins containing a cyclic ether structure, a resin having a vinyl group is preferred. By using an unsaturated resin containing a cyclic ether structure having a vinyl group (i.e., a resin having a cyclic ether structure having a vinyl group as a free radical polymerizable unsaturated group and having a 5-membered ring or more) as the unsaturated resin (C), the desired effect of the present invention can be significantly obtained. Furthermore, the dielectric tangent of the resin composition can usually be effectively reduced.

When enumerating preferred examples of the unsaturated resin (C), there can be listed compounds represented by the following formula (C1), compounds represented by the following formula (C6), compounds represented by the following formula (C7), compounds represented by the following formula (C9), and compounds represented by the following formula (C10). Among them, it is particularly preferred that the compound represented by the formula (C7) is an unsaturated resin containing a cyclic ether structure. The unsaturated resin (C) may also be a benzocyclobutene resin.

In formula (C1), R ¹ to R ⁶ each independently represent a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, preferably a hydrogen atom. In formula (C1), A represents a divalent group represented by the following formula (C2) or the following formula (C3).

In formula (C2), B represents a divalent group represented by the following formula (C2-1), (C2-2) or (C2-3).

In formula (C2-1), R ¹⁵ to R ¹⁸ each independently represent a hydrogen atom, an alkyl group having 6 or less carbon atoms, or a phenyl group, preferably a hydrogen atom or a methyl group. In formula (C2-2), R ¹⁹ to R ²⁶ each independently represent a hydrogen atom, an alkyl group having 6 or less carbon atoms, or a phenyl group, preferably a hydrogen atom or a methyl group. In formula (C2-3), R ²⁷ to R ³⁴ each independently represent a hydrogen atom, an alkyl group having 6 or less carbon atoms, or a benzene group, preferably a hydrogen atom or a methyl group. In formula (C2-3), E represents a linear, branched, or cyclic divalent hydrocarbon group having 20 or less carbon atoms.

In formula (C3), D represents a divalent group represented by the following formula (C4).

In formula (C4), ^R7 to ^R14 independently represent a hydrogen atom, an alkyl group having 6 or less carbon atoms, or a phenyl group, preferably a hydrogen atom or a methyl group. In particular, ^R7 , ^R8 , ^R13 , and ^R14 are more preferably methyl groups. In formula (C4), at least one of a and b is not 0 but an integer of 0 to 100. In formula (C4), B represents a divalent group represented by the aforementioned formula (C2-1), (C2-2), or (C2-3).

The compound represented by the aforementioned formula (C1) is preferably a compound represented by the following formula (C5).

In formula (C5), R ¹ to R ⁶ have the same meanings as R ¹ to R ⁶ in the aforementioned formula (C1), B has the same meaning as B in the aforementioned formula (C2), and a and b have the same meanings as a and b in the aforementioned formula (C4).

In formula (C7), ring F represents a divalent group having a cyclic ether structure having 5 or more members. The range of the cyclic ether structure is as described above. In addition, the cyclic ether structure may have a substituent as described above.

Examples of the divalent group having a cyclic ether structure having five or more ring members include furan-2,5-diyl, tetrahydrofuran-2,5-diyl, dioxolane-2,5-diyl, pyran-2,5-diyl, dihydropyran-2,5-diyl, tetrahydropyran-2,5-diyl, 1,2-dioxane-3,6-diyl, 1,3-dioxane-2,5-diyl, 1,4-dioxane-2,5-diyl, and 5-ethyl-1,3-dioxane-2,5-diyl. Among them, 5-ethyl-1,3-dioxane-2,5-diyl is preferred.

In formula (C7), ^B1 and ^B2 each independently represent a single bond or a divalent linking group. ^B1 and ^B2 are preferably divalent linking groups. Examples of divalent linking groups include alkylene groups which may have a substituent, alkenylene groups which may have a substituent, alkynylene groups which may have a substituent, arylene groups which may have a substituent, heteroarylene groups which may have a substituent, groups represented by -COO-, groups represented by -CO-, groups represented by -CONH-, groups represented by -NHCONH-, groups represented by -NHCOO-, groups represented by -C(=O)-, groups represented by -S-, groups represented by -SO-, groups represented by -NH-, and groups in which these groups are combined in plural numbers.

Among these, ^B1 and ^B2 are preferably a group selected from the group consisting of an alkylene group which may have a substituent, an alkenylene group which may have a substituent, an alkynylene group which may have a substituent, a group represented by -COO-, and a group represented by -O-. In particular, ^B1 and ^B2 are more preferably a group selected from the group consisting of an alkylene group which may have a substituent and a group represented by -COO-.

In formula (C7), ^C1 and ^C2 each independently represent a functional group. Examples of the functional group include vinyl, methacryl, acryl, allyl, styryl, propenyl, and epoxy. In a suitable embodiment, ^C1 and ^C2 are vinyl.

As specific examples of the compound represented by formula (C7), there can be mentioned the compound represented by the following formula (C8).

In the formula (C10), n represents 1 to 5.

Examples of the unsaturated resin (C) include "OPE-2St 1200" manufactured by Mitsubishi Gas Chemical Co., Ltd. (styrene-modified polyphenylene ether resin, number average molecular weight 1200, equivalent to the above formula (C5)), "YL7776" manufactured by Mitsubishi Chemical Co., Ltd. (bis(dimethylphenol) diallyl ether resin, number average molecular weight 331, equivalent to the above formula (C6)), "A-DOG" manufactured by Shin-Nakamura Chemical Co., Ltd. (dioxane acryloyl monomer glycol diacrylate, number average molecular weight 326, equivalent to the above formula (C8)), and "KAYARAD" manufactured by Nippon Kayaku Co., Ltd. R-604" (equivalent to the aforementioned formula (C8)), "A-DCP" manufactured by Shin-Nakamura Chemical Industry Co., Ltd. (tricyclodecanedimethanol diacrylate, number average molecular weight 304, equivalent to the aforementioned formula (C9)), and "MIR-3000-70MT" manufactured by Nippon Kayaku Co., Ltd., equivalent to the aforementioned formula (C10)). In addition, the unsaturated resin (C) may be used alone or in combination of two or more.

The number average molecular weight of the unsaturated resin (C) is preferably 100 or more, more preferably 200 or more, preferably 10,000 or less, more preferably 3,000 or less. When the number average molecular weight of the unsaturated resin (C) is within the above range, volatility during drying of the resin varnish can be suppressed, or the melt viscosity of the resin composition can be suppressed from becoming too large. The number average molecular weight can be measured by gel permeation chromatography (GPC) as a value converted to polystyrene. The number average molecular weight can be measured by the GPC method, for example, using "LC-9A/RID-6A" manufactured by Shimadzu Corporation as a measuring apparatus, "Shodex K-800P/K-804L/K-804L" manufactured by Showa Denko K.K. as a column, and chloroform as a mobile phase, and the measurement can be performed at a column temperature of 40°C.

The content of the component (C) in the resin composition is preferably 1% by mass or more, more preferably 3% by mass or more or 5% by mass or more, from the viewpoint of obtaining a resin composition having a low dielectric tangent. The upper limit of the content of the component (C) is preferably 20% by mass or less, more preferably 15% by mass or less or 10% by mass or less, from the viewpoint of improving the compatibility of the resin composition.

<(D) Aliphatic phosphine compound> The resin composition of the present invention contains an aliphatic phosphine compound as the (D) component. By combining the (D) component with the aforementioned (C) component, a resin composition having a low dielectric tangent and excellent coating adhesion and substrate adhesion can be obtained.

As mentioned above, by adding component (C), the dielectric tangent of the cured product of the resin composition can be reduced. However, on the other hand, the inventors found that the cured product had poor coating adhesion and substrate adhesion. As a result of the inventors' intensive research on this topic, by adding component (D) in combination with component (C), the dielectric tangent of the cured product of the resin composition can be reduced. In other words, the advantages of component (C) are directly maintained, and a resin composition with excellent coating adhesion and substrate adhesion is finally achieved.

As mentioned above, the (D) component is characterized by containing phosphorus atoms directly bonded to aliphatic carbon atoms. In this regard, the inventors of the present invention have confirmed that even if it is an organic phosphine compound, if it does not have phosphorus atoms directly bonded to aliphatic carbon atoms, it is impossible to achieve the desired effect when combined with the (C) component (Comparative Example 2 described below). By showing that the electron-extracting aliphatic carbon atoms are directly bonded to the phosphorus atoms, the phosphorus atoms become electron-rich. The electron-rich phosphorus atoms are believed to promote the reaction between the (A) component and the (C) component, and reproduce the cured composition that helps the adhesion to the conductor. From the perspective of achieving a resin composition that brings about a cured product with better coating adhesion and substrate adhesion, the (D) component is preferably a phosphorus atom that contains both aliphatic carbon atoms and aromatic carbon atoms.

The number of phosphorus atoms directly bonded to aliphatic carbon atoms contained in component (D) per molecule is not particularly limited, but is generally 1 to 10, preferably 1 to 8, more preferably 1 to 6, 1 to 4 or 1 to 3, and even more preferably 1 or 2. Component (D) may contain phosphorus atoms not directly bonded to aliphatic carbon atoms in the molecule as long as it contains phosphorus atoms directly bonded to aliphatic carbon atoms.

The number of aliphatic carbon atoms contained in each molecule of component (D) is not particularly limited, but is preferably 2 or more, more preferably 3 or more or 4 or more. Here, the number of aliphatic carbon atoms refers to the total number of carbon atoms other than aromatic carbon atoms contained in component (D). For example, when component (D) has 2 phenyl groups and 1 cyclohexyl group in one molecule, the number of aliphatic carbon atoms is 6. Furthermore, when component (D) has 1 phenyl group and 2 cyclooctyl groups in one molecule, the number of aliphatic carbon atoms is 16. The upper limit of the number of aliphatic carbon atoms contained in each molecule of component (D) is not particularly limited, but is generally 100 or less, preferably 80 or less, more preferably 60 or less, and even more preferably 40 or less, 20 or less, 12 or less, or 8 or less.

In one embodiment, the component (D) is a compound represented by the following formula (D1) or formula (D2).

(In formula (D1), ^Rd1 and ^Rd2 each independently represent a hydrogen atom or a monovalent group represented by the formula: -(RO) _l -R', wherein l represents an integer from 0 to 5, R represents a divalent aromatic group which may have a substituent, or a divalent aliphatic group which may have a substituent, R' represents a monovalent aromatic group which may have a substituent, or a monovalent aliphatic group which may have a substituent, and when R' exists in plural, they may be the same as or different from each other, ^Rd3 represents a monovalent group represented by the formula: -(R''-O) _m -R''', wherein m represents an integer from 0 to 5, R'' represents a divalent aliphatic group which may have a substituent, R''' represents a monovalent aliphatic group which may have a substituent, and when R'' exists in plural, they may be the same as or different from each other). (In formula (D2), ^Rd1 and ^Rd2 have the same meanings as above, L represents a divalent group represented by the formula: -(R''-O) _n -R''-, wherein n represents an integer from 0 to 5, R'' has the same meaning as above, and when R'' exists in plural numbers, they may be the same as or different from each other, ^Rd4 and ^Rd5 each independently represent a hydrogen atom, a monovalent group represented by the formula: -(RO) _l -R' or a monovalent group represented by the formula: -LP( ^-Rd1 )(- ^Rd2 ), wherein l, R, R', L, ^Rd1 and ^Rd2 have the same meanings as above).

In formula (D1), ^Rd1 and ^Rd2 each independently represent a hydrogen atom or a monovalent group represented by the formula: -(RO) _l -R'. l represents an integer of 0 to 5, R represents a divalent aromatic group which may have a substituent, or a divalent aliphatic group which may have a substituent, and R' represents a monovalent aromatic group which may have a substituent, or a monovalent aliphatic group which may have a substituent. When R is present in plural numbers, they may be the same or different from each other. In a suitable embodiment, at least one of ^Rd1 and ^Rd2 represents a monovalent group represented by the formula: -(RO) _l -R', and R (when l=1 to 5) and R' (when l=0) directly bonded to the phosphorus atom represent a divalent aromatic group which may have a substituent, or a monovalent aromatic group which may have a substituent, respectively.

In the present specification, the so-called "divalent aromatic group" refers to a group obtained by removing two hydrogen atoms from an aromatic ring of an aromatic compound. In a suitable embodiment, the divalent aromatic group includes an aryl group and a heteroaryl group. The so-called heteroaryl group refers to a group obtained by removing two hydrogen atoms from a heterocyclic ring of an aromatic heterocyclic compound. The so-called heterocyclic ring refers to a ring containing not only carbon atoms but also heteroatoms such as oxygen atoms, sulfur atoms, nitrogen atoms, phosphorus atoms, boron atoms and silicon atoms as atoms constituting the ring. Furthermore, in the present specification, the so-called "monovalent aromatic group" refers to a group obtained by removing one hydrogen atom from an aromatic ring of an aromatic compound, and in a suitable embodiment, includes an aryl group and a heteroaryl group. A heteroaryl group is a group obtained by removing one hydrogen atom from a heterocyclic ring of an aromatic heterocyclic compound, and is the same as a heteroaryl group except that the number of hydrogen atoms removed from the heterocyclic ring is one.

In this specification, the so-called "divalent aliphatic group" refers to a group obtained by removing two hydrogen atoms from an aliphatic compound. Here, the aliphatic compound may be a saturated aliphatic compound or an unsaturated aliphatic compound. In a suitable embodiment, the divalent aliphatic group includes an alkylene group, an alkenylene group, a cycloalkylene group, a cycloalkenylene group, a heterocycloalkylene group, and a heterocycloalkenylene group. The so-called heterocycloalkylene group refers to a group obtained by removing two hydrogen atoms from a heterocycle of a saturated aliphatic heterocyclic compound (i.e., a saturated heterocycle), and the so-called heterocycloalkenylene group refers to a group obtained by removing two hydrogen atoms from a heterocycle of an unsaturated aliphatic heterocyclic compound having a carbon-carbon double bond (i.e., an unsaturated heterocycle having a carbon-carbon double bond). The heteroatoms contained in the heterocycle are the same as those described above. In addition, in this specification, the so-called "monovalent aliphatic group" refers to a group obtained by removing one hydrogen atom from an aliphatic compound. In a suitable embodiment, the monovalent aliphatic group includes an alkyl group, an alkenyl group, a cycloalkyl group, a cycloalkenyl group, a heterocycloalkyl group, and a heterocycloalkenyl group. A heterocycloalkyl group refers to a group obtained by removing one hydrogen atom from a heterocyclic ring of a saturated aliphatic heterocyclic compound, and is the same as a heterocycloalkylene group except that the number of hydrogen atoms removed from the heterocyclic ring is one. A heterocycloalkenyl group refers to a group obtained by removing one carbon atom from a heterocyclic ring of an unsaturated aliphatic heterocyclic compound having a carbon-carbon double bond, and is the same as a heterocycloalkenylene group except that the number of hydrogen atoms removed from the heterocyclic ring is one.

l is preferably an integer from 0 to 3, more preferably an integer from 0 to 2, further preferably 0 or 1, and further preferably 0.

In a suitable embodiment, R represents an arylene group which may have a substituent, a heteroarylene group which may have a substituent, an alkylene group which may have a substituent, an alkenylene group which may have a substituent, a cycloalkylene group which may have a substituent, a cycloalkenylene group which may have a substituent, a heterocycloalkylene group which may have a substituent, or a heterocycloalkenylene group which may have a substituent.

The number of carbon atoms in the arylene group of R is preferably 6 to 24, more preferably 6 to 18, further preferably 6 to 14, and further preferably 6 to 10. Specific examples of the arylene group include phenylene, naphthyl, and anthracenylene.

The number of carbon atoms in the heteroaryl group of R is preferably 3 to 21, more preferably 3 to 15, further preferably 3 to 9, and further preferably 3 to 6. Specific examples of the heteroaryl group include pyrenediyl, pyrrolediyl, furandiyl, thiophenediyl, pyridinediyl, oxazinediyl, pyrimidinediyl, pyrazinediyl, triazinediyl, pyrrolinediyl, piperidinediyl, triazolediyl, purinediyl, anthraquinonediyl, carbazolediyl, fluorenediyl, quinolinediyl, and isoquinolinediyl.

The alkylene group in R may be either linear or branched, and the number of carbon atoms is preferably 1 to 12, more preferably 1 to 9, and even more preferably 1 to 6 or 1 to 4. Specific examples of the alkylene group include methylene, ethyl, propyl, butyl, pentyl, hexyl, heptyl, octyl, nonyl, decyl, undecyl, and dodecyl.

The alkenylene group in R may be either linear or branched, and preferably has 2 to 12 carbon atoms, more preferably 2 to 9, and even more preferably 2 to 6 or 2 to 4. Specific examples of the alkenylene group include ethenylene, propenylene, butenylene, pentenylene, hexenylene, heptenylene, octenylene, nonenylene, decenylene, undecenylene, and dodecenylene.

The number of carbon atoms in the cycloalkylene group of R is preferably 3 to 12, more preferably 3 to 10, 3 to 8 or 3 to 6. Specific examples of the cycloalkylene group include cyclopropylene, cyclobutylene, cyclopentylene, cyclohexylene, decahydronaphthylene, norbornanylene and adamantylene.

The number of carbon atoms of the cycloalkenylene group in R is preferably 3 to 10, more preferably 3 to 6. Specific examples of the cycloalkenylene group include cyclopropenylene, cyclobutenylene, cyclopentenylene, cyclohexenylene and norbornenylene.

The number of carbon atoms in the heterocycloalkylene group of R is preferably 2 to 21, more preferably 2 to 15, and even more preferably 2 to 9, 2 to 6, or 2 to 5. The hetero atom constituting the heterocycloalkylene group preferably includes at least one selected from the group consisting of oxygen atoms, sulfur atoms, nitrogen atoms, phosphorus atoms, boron atoms, and silicon atoms, and more preferably includes at least one selected from the group consisting of oxygen atoms, sulfur atoms, and nitrogen atoms. Specific examples of the heterocycloalkylene group include oxiranediyl, aziridinediyl, azetidinediyl, oxiranediyl, thiodiyl, pyrrolidinediyl, dihydrofurandiyl, and tetrahydrofurandiyl.

The number of carbon atoms in the heterocycloalkenyl group of R is preferably 2 to 21, more preferably 2 to 15, and even more preferably 2 to 9, 2 to 6, or 2 to 5. Suitable heteroatoms are the same as those described for the heterocycloalkylene group. Specific examples of the heterocycloalkenylene group include aryloxyheteropropylene (oxylene) diyl and oxycyclobutene (oxetene) diyl.

The substituents that may be present in the divalent group of R are as described above. When the divalent group of R has a plurality of substituents, they may be the same or different.

In a suitable embodiment, R' represents an aryl group which may have a substituent, a heteroaryl group which may have a substituent, an alkyl group which may have a substituent, an alkenyl group which may have a substituent, a cycloalkyl group which may have a substituent, a cycloalkenyl group which may have a substituent, a heterocycloalkyl group which may have a substituent, or a heterocycloalkenyl group which may have a substituent.

Suitable numbers of carbon atoms in the aryl, heteroaryl, alkyl, alkenyl, cycloalkyl, cycloalkenyl, heterocycloalkyl and heterocycloalkenyl groups in R' are the same as those described for the arylene, heteroarylene, alkyllene, alkenylene, cycloalkyllene, cycloalkenylene, heterocycloalkyllene and heterocycloalkenylene groups in R, respectively.

In formula (D1), R ^d3 represents a monovalent group represented by the formula: -(R''-O) _m -R''', wherein m represents an integer of 0 to 5, R'' represents a divalent aliphatic group which may have a substituent, and R''' represents a monovalent aliphatic group which may have a substituent. When R'' exists in plural, they may be the same or different from each other.

m is preferably an integer from 0 to 3, more preferably an integer from 0 to 2, further preferably 0 or 1, and further preferably 0.

In a suitable embodiment, R″ represents an alkylene group which may have a substituent, an alkenylene group which may have a substituent, a cycloalkylene group which may have a substituent, a cycloalkenylene group which may have a substituent, a heterocycloalkylene group which may have a substituent, or a heterocycloalkenylene group which may have a substituent.

In a suitable embodiment, R''' represents an alkyl group which may have a substituent, an alkenyl group which may have a substituent, a cycloalkyl group which may have a substituent, a cycloalkenyl group which may have a substituent, a heterocycloalkyl group which may have a substituent, or a heterocycloalkenyl group which may have a substituent.

The suitable number of carbon atoms of the alkylene, alkenylene, cycloalkylene, cycloalkenylene, heterocycloalkylene and heterocycloalkenylene in R″ is the same as the suitable number of carbon atoms explained for the alkylene, alkenylene, cycloalkylene, cycloalkenylene, heterocycloalkylene and heterocycloalkenylene in R, respectively. Furthermore, the suitable number of carbon atoms of the alkyl, alkenyl, cycloalkyl, cycloalkenyl, heterocycloalkylene and heterocycloalkenyl in R″ is the same as the suitable number of carbon atoms explained for the alkylene, alkenylene, cycloalkylene, cycloalkenylene, heterocycloalkylene and heterocycloalkenyl in R, respectively.

When R'' is a heterocycloalkylene group (or heterocycloalkenylene group) which may have a substituent, the carbon atom constituting the heterocycloalkylene group (or heterocycloalkenylene group) is bonded to the phosphorus atom. When m is 0 and R''' is a heterocycloalkylene group (or heterocycloalkenyl group) which may have a substituent, the carbon atom constituting the heterocycloalkylene group (or heterocycloalkenyl group) is bonded to the phosphorus atom.

In one embodiment, in formula (D1), i) either ^Rd1 or ^Rd2 is a monovalent group represented by the formula: -(RO) _l -R', l is 0, and R' represents an aryl group which may have a substituent, ii) ^Rd3 is a monovalent group represented by the formula: -(R''-O) _m -R''', m is an integer from 0 to 2, R'' is an alkylene group which may have a substituent or a cycloalkylene group which may have a substituent, and R''' is an alkylene group which may have a substituent, an alkenyl group which may have a substituent, or a cycloalkyl group which may have a substituent.

In a suitable embodiment, in formula (D1), i) either ^Rd1 or ^Rd2 is a monovalent group represented by the formula: -(RO) _l -R', l is 0, and R' is a phenyl group which may have a substituent, ii) ^Rd3 is a monovalent group represented by the formula: -(R''-O) _m -R''', m is 0, and R''' is a cycloalkyl group which may have a substituent.

In another embodiment, in formula (D1), i) R ^d1 is a monovalent group represented by the formula: -(RO) _l -R', l is 0, and R' is an aryl group which may have a substituent, ii) R ^d2 is a monovalent group represented by the formula: -(RO) _l -R', l is 0, and R' is an alkyl group which may have a substituent or an alkenyl group which may have a substituent, iii) R ^d3 is a monovalent group represented by the formula: -(R''-O) _m -R''', m is an integer of 0 to 2, R'' is an alkyl group which may have a substituent or a cycloalkyl group which may have a substituent, and R''' is an alkyl group which may have a substituent, an alkenyl group which may have a substituent, or a cycloalkyl group which may have a substituent.

In another suitable embodiment, in formula (D1), i) R ^d1 is represented by the formula: a monovalent group represented by -(RO) _l -R', l is 0, and R' is a phenyl group which may have a substituent, ii) R ^d1 is represented by the formula: a monovalent group represented by -(RO) _l -R', l is 0, and R' is an alkyl group which may have a substituent, iii) R ^d3 is represented by the formula: a monovalent group represented by -(R''-O) _m -R''', m is 0, and R''' is an alkyl group which may have a substituent.

In formula (D2), R ^d1 and R ^d2 have the same meanings as above, that is, the same meanings as R ^d1 and R ^d2 in formula (D1).

In formula (D2), L represents a divalent group represented by the formula: -(R''-O) _n -R''-. n represents an integer of 0 to 5, and R'' has the same meaning as above, that is, it has the same meaning as R'' described for R ^d3 in formula (D1). When R'' exists in plural, they may be the same as or different from each other.

n is preferably an integer from 0 to 3, more preferably an integer from 0 to 2, further preferably 0 or 1, and further preferably 0.

In formula (D2), ^Rd4 and ^Rd5 independently represent a hydrogen atom, a monovalent group represented by the formula: -(RO) _l -R' or a monovalent group represented by the formula: -LP( ^-Rd1 )(- ^Rd2 ), wherein I, R, R', L, ^Rd1 and ^Rd2 have the same meanings as above.

In one embodiment, in formula (D2), i) either ^Rd1 or ^Rd2 is a monovalent group represented by the formula: -(RO) _l -R', l is 0, and R' is an aryl group which may have a substituent, ii) L is a divalent group represented by the formula: -(R''-O) _n -R''-, n is an integer from 0 to 2, and R'' is an alkylene group which may have a substituent or a cycloalkylene group which may have a substituent, iii) either ^Rd4 or ^Rd5 is a monovalent group represented by the formula: -(RO) _l -R', l is 0, and R' is an aryl group which may have a substituent.

In a suitable embodiment, in formula (D2), i) either ^Rd1 or ^Rd2 is a monovalent group represented by the formula: -(RO) _l -R', l is 0, and R' is a phenyl group which may have a substituent, ii) L is a divalent group represented by the formula: -(R''-O) _n -R''-, n is 0, and R'' is an alkylene group which may have a substituent, iii) either ^Rd4 or ^Rd5 is a monovalent group represented by the formula: -(RO) _l -R', l is 0, and R' is a phenyl group which may have a substituent.

In one embodiment, the component (D) comprises a compound represented by any of the following formulae.

Examples of the component (D) include "DPPE" (1,3-bisdiphenylphosphinoethane), "DPPP" (1,3-bisdiphenylphosphinopropane), "DPPB" (1,3-bisdiphenylphosphinobutane), "DPCP" (diphenylcyclohexylphosphine), "TCHP" (tricyclohexylphosphine), and "Amphos" ([4-(N,N-dimethylamino)phenyl]di-tert-butylphosphine) manufactured by Hokushin Chemical Co., Ltd.

When the total amount of the resin components in the resin composition is defined as 100 mass %, even when the content of the component (D) is as low as 0.001 mass %, in combination with the component (C), a resin composition can be realized which provides a cured product having a low dielectric tangent and excellent coating adhesion and substrate adhesion. The content of the component (D) in the resin composition is preferably 0.001% by mass or more, more preferably 0.01% by mass or more, 0.05% by mass or more, 0.1% by mass or more, 0.2% by mass or more, 0.3% by mass or more, or 0.5% by mass or more, from the viewpoint of achieving a resin composition having a cured product with significantly excellent coating adhesion and substrate adhesion in combination with the component (C), when the total of the resin components in the resin composition is taken as 100% by mass. In addition, the so-called "resin component" refers to the component excluding the (E) inorganic filler described later from the non-volatile components constituting the resin composition.

As mentioned above, the component (D) has phosphorus atoms directly bonded to aliphatic carbon atoms. The electron-rich phosphorus atoms are considered to promote the reaction between the components (A) and (C), and reproduce the cured composition that helps the adhesion to the conductor. Due to the high reaction-promoting effect, when the component (D) is blended, the melt viscosity of the resin composition increases with time. Therefore, when the storage time from the preparation of the resin composition to its use is long, the resin composition may become noticeably thicker due to the usage. In this regard, when the total amount of the resin components in the resin composition is set to 100% by mass, the thickening can be effectively suppressed by setting the content of the component (D) to 10% by mass or less. The upper limit of the content of the component (D) is preferably 10% by mass or less, more preferably 8% by mass or less, 6% by mass or less, 5% by mass or less, or 3% by mass or less, from the viewpoint of obtaining a resin composition with a good pot life.

The resin composition of the present invention may further contain one or more additives selected from the group consisting of inorganic fillers, curing accelerators, indole resins, thermoplastic resins, flame retardants and organic fillers, if necessary.

-(E) Inorganic filler- The resin composition of the present invention may further include an inorganic filler as the (E) component. By including the inorganic filler, a cured product with a lower linear thermal expansion coefficient and dielectric tangent can be achieved.

Although the material of the inorganic filler is not particularly limited, examples thereof include silicon dioxide, aluminum oxide, glass, cordierite, silicon oxide, barium sulfate, barium carbonate, talc, clay, mica powder, zinc oxide, hydrotalcite, boehmite, aluminum hydroxide, magnesium hydroxide, calcium carbonate, magnesium carbonate, magnesium oxide, boron nitride, aluminum nitride, manganese nitride, aluminum borate, strontium carbonate, strontium titanate, calcium titanate, magnesium titanate, bismuth titanate, titanium oxide, zirconium oxide, barium titanate, barium zirconate, barium zirconate, calcium zirconate, zirconium phosphate, and zirconium tungstate phosphate, and silicon dioxide is particularly suitable. As silica, for example, amorphous silica, fused silica, crystalline silica, synthetic silica, hollow silica, etc. can be listed. Moreover, as silica, spherical silica is preferred. The inorganic filler can be used alone or in combination of two or more. As commercially available spherical silica, "SO-C2" and "SO-C1" manufactured by Admatechs, "IMSIL A-8" and "IMSIL A-10" manufactured by Unimin, etc. can be listed.

The average particle size of the inorganic filler is preferably 4 μm or less, more preferably 3 μm or less, further preferably 2.5 μm or less, further preferably 2 μm or less, particularly preferably 1 μm or less, 0.7 μm or less, or 0.5 μm or less. The lower limit of the average particle size of the inorganic filler is preferably 0.01 μm or more, more preferably 0.03 μm or more, further preferably 0.05 μm or more, 0.07 μm or more, or 0.1 μm or more. The average particle size of the inorganic filler can be measured by the laser diffraction scattering method based on the Mie scattering theory. Specifically, the particle size distribution of the inorganic filler is made on a volume basis by a laser diffraction particle size distribution measuring device, and the median diameter thereof is used as the average particle size for measurement. The sample to be measured can preferably be an inorganic filler dispersed in water by ultrasonic waves. As a laser diffraction particle size distribution measuring device, "LA-500", "LA-750", "LA-950" and the like manufactured by HORIBA, Ltd. can be used. In addition, from the viewpoint of significantly obtaining the effect of the present invention, 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 5 m ² /g or more. Although there is no particular upper limit, it 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 of the inorganic filler can be measured by the BET method.

From the viewpoint of improving moisture resistance and dispersibility, the inorganic filler is preferably treated with one or more surface treatment agents such as aminosilane coupling agents, epoxysilane coupling agents, butylsilane coupling agents, alkoxysilane compounds, organic silazane compounds, and titanium ester coupling agents. Examples of commercially available surface treatment agents include "KBM403" (3-glycidoxypropyltrimethoxysilane) manufactured by Shin-Etsu Chemical Co., Ltd., "KBM803" (3-butylenepropyltrimethoxysilane) manufactured by Shin-Etsu Chemical Co., Ltd., "KBE903" (3-aminopropyltriethoxysilane) manufactured by Shin-Etsu Chemical Co., Ltd., "KBM573" (N-phenyl-3-aminopropyltrimethoxysilane) manufactured by Shin-Etsu Chemical Co., Ltd., and "SZ-31" (hexamethyldisilazane) manufactured by Shin-Etsu Chemical Co., Ltd.

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

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

From the viewpoint of obtaining a cured product with low linear thermal expansion coefficient and dielectric tangent, the content of the inorganic filler in the resin composition is preferably 50% by mass or more, more preferably 55% by mass or more, 60% by mass or more, 65% by mass or more, or 70% by mass or more. From the viewpoint of the mechanical strength of the cured product obtained, the upper limit of the content of the inorganic filler in the resin composition is preferably 90% by mass or less, more preferably 85% by mass or less, and even more preferably 80% by mass or less.

-(F) Hardening accelerator- The resin composition of the present invention may further contain a hardening accelerator as the (F) component. Examples of the hardening accelerator include amine-based hardening accelerators, imidazole-based hardening accelerators, guanidine-based hardening accelerators, metal-based hardening accelerators, and peroxide-based hardening accelerators. Among them, amine-based hardening accelerators, imidazole-based hardening accelerators, and peroxide-based hardening accelerators are preferred. The hardening accelerator may be used alone or in combination of two or more. When a hardening accelerator is used, the content of the hardening accelerator in the resin composition is preferably 0.005% by mass to 1% by mass, and more preferably 0.01% by mass to 0.5% by mass.

-(G) Indole Resin- The resin composition of the present invention may further include an indole resin as the (G) component. By including the indole resin, the advantageous effect of the present invention by combining the (C) component and the (D) component for blending can be further enhanced. Examples of the indole resin include copolymers of indene and coumarone, and copolymers of indene, coumarone, and styrene. Specific examples of the indole resin include "H-100", "V-120S", and "V-120" manufactured by Nichiko Chemical Co., Ltd. The indole resin may be used alone or in combination of two or more. When an indenone resin is used, the content of the indenone resin in the resin composition is preferably 1 to 4 mass %, more preferably 2 to 3.5 mass %, from the viewpoint of obtaining a resin composition with good compatibility.

-Thermoplastic resin- The resin composition of the present invention may further include a thermoplastic resin. Examples of the thermoplastic resin include phenoxy resins, polyvinyl acetal resins, polyolefin resins, polybutadiene resins, polyimide resins, polyamide imide resins, polyether imide resins, polysulfone resins, polyethersulfone resins, polyphenylene ether resins, polycarbonate resins, polyetheretherketone resins, and polyester resins. The thermoplastic resin may be used alone or in combination of two or more.

The weight average molecular weight of the thermoplastic resin in terms of polystyrene is preferably in the range of 8,000 to 70,000, more preferably in the range of 10,000 to 60,000, and even more preferably in the range of 20,000 to 60,000. The weight average molecular weight of the thermoplastic resin in terms of polystyrene is measured by gel permeation chromatography (GPC). Specifically, the weight average molecular weight of the thermoplastic resin in terms of polystyrene is measured using LC-9A/RID-6A manufactured by Shimadzu Corporation as a measuring device, Shodex K-800P/K-804L/K-804L manufactured by Showa Denko Co., Ltd. as a column, and chloroform or the like as a mobile phase at a column temperature of 40°C, and can be calculated using a calibration curve of standard polystyrene.

Examples of phenoxy resins include phenoxy resins having one or more skeletons selected from the group consisting of bisphenol A skeleton, bisphenol F skeleton, bisphenol S skeleton, bisphenol acetophenone skeleton, phenolic skeleton, biphenyl skeleton, fluorene skeleton, dicyclopentadiene skeleton, norbornene skeleton, naphthalene skeleton, anthracene skeleton, adamantane skeleton, terpene skeleton, and trimethylcyclohexane skeleton. The terminal of the phenoxy resin may be any functional group such as a phenolic hydroxyl group or an epoxy group. The phenoxy resin may be used alone or in combination of two or more. Specific examples of phenoxy resins include "1256" and "4250" (both phenoxy resins containing a bisphenol A skeleton), "YX8100" (phenoxy resin containing a bisphenol S skeleton), and "YX6954" (phenoxy resin containing a bisphenol acetophenone skeleton) manufactured by Mitsubishi Chemical Co., Ltd. Other examples include "FX280" and "FX293" manufactured by Nippon Steel & Sumitomo Metal Chemical Co., Ltd., and "YX7553", "YL6794", "YL7213", "YL7290", and "YL7482" manufactured by Mitsubishi Chemical Co., Ltd.

Examples of polyvinyl acetal resins include polyvinyl formaldehyde resins and polyvinyl butyral resins, and polyvinyl butyral resins are preferred. Specific examples of polyvinyl acetal resins include "Electrochemical Butyral 4000-2", "Electrochemical Butyral 5000-A", "Electrochemical Butyral 6000-C", "Electrochemical Butyral 6000-EP" manufactured by Denki Kagaku Kogyo Co., Ltd., and S-LEC BH series, BX series, KS series, BL series, BM series, etc. manufactured by Sekisui Chemical Kogyo Co., Ltd.

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

As specific examples of polyamide imide resins, "VYLOMAX HR11NN" and "VYLOMAX HR16NN" manufactured by Toyobo Co., Ltd. are listed. As specific examples of polyamide imide resins, modified polyamide imides such as polyamide imide "KS9100" and "KS9300" containing a polysiloxane skeleton manufactured by Hitachi Chemical Industries, Ltd. are listed.

As a specific example of the polyether sulphate resin, "PES5003P" manufactured by Sumitomo Chemical Co., Ltd. can be cited.

Specific examples of the polyol resin include polyols "P1700" and "P3500" manufactured by Solvay Specialty Polymers Co., Ltd.

When a thermoplastic resin is used, the content of the thermoplastic resin in the resin composition is preferably 0.1 mass % to 20 mass %, more preferably 0.2 mass % to 10 mass %, and even more preferably 0.3 mass % to 5 mass %.

-Flame retardant- The resin composition of the present invention may further contain a flame retardant. Examples of the flame retardant include organic phosphorus flame retardants, phosphorus compounds containing organic nitrogen, nitrogen compounds, polysilicone flame retardants, metal hydroxides, etc. The flame retardant may be used alone or in combination of two or more. When the flame retardant is used, the content of the flame retardant in the resin composition is not particularly limited, but is preferably 0.1% by mass to 15% by mass, and more preferably 0.5% by mass to 10% by mass.

-Organic filler- The resin composition of the present invention may further include an organic filler. As the organic filler, any organic filler that can be used when forming an insulating layer of a printed wiring board can be used, for example, rubber particles, polyamide microparticles, polysilicone particles, etc., preferably rubber particles.

The rubber particles are obtained by chemically crosslinking a resin exhibiting rubber elasticity. The particles are not particularly limited as long as they are fine particles of a resin that is insoluble and infusible in an organic solvent. Examples thereof include acrylonitrile butadiene rubber particles, butadiene rubber particles, and acryl rubber particles. Specific examples of the rubber particles include XER-91 (manufactured by Nippon Synthetic Rubber Co., Ltd.), STAPHYLOID AC3355, AC3816, AC3816N, AC3832, AC4030, AC3364, and IM101 (manufactured by AICA Industries Co., Ltd.), and PARALOID EXL2655 and EXL2602 (manufactured by Kureha Chemical Industries Co., Ltd.).

The average particle size of the organic filler is preferably in the range of 0.005 μm to 1 μm, and more preferably in the range of 0.2 μm to 0.6 μm. The average particle size of the organic filler can be measured using a dynamic light scattering method. For example, the organic filler can be uniformly dispersed in an appropriate organic solvent by ultrasound or the like, and the particle size distribution of the organic filler can be made on a mass basis using a concentration-based particle size analyzer ("FPAR-1000" manufactured by Otsuka Electronics Co., Ltd.), and the median diameter is measured as the average particle size. When an organic filler is used, the content of the organic filler in the resin composition is preferably 1 mass % to 10 mass %, and more preferably 2 mass % to 5 mass %, when the non-volatile components in the resin composition are set to 100 mass %.

The resin composition of the present invention may contain other components if necessary. Examples of such other components include organic metal compounds such as organic copper compounds, organic zinc compounds, and organic cobalt compounds, and resin additives such as thickeners, defoamers, levelers, adhesion enhancers, and colorants.

The method for preparing the resin composition of the present invention is not particularly limited, and examples thereof include a method of adding a solvent to the blending components as necessary and mixing and dispersing the components using a rotary mixer or the like.

The resin composition of the present invention can bring about a cured product with a low dielectric tangent. The dielectric tangent of the cured product of the resin composition of the present invention can be measured by the method described in <Measurement of dielectric tangent> described later. Specifically, it can be measured by the cavity resonance propagation method at a frequency of 5.8 GHz and a measurement temperature of 23°C. From the perspective of preventing high-frequency heat generation, signal delay, and signal noise reduction, the dielectric tangent is preferably less than 0.010, more preferably less than 0.009, less than 0.008, less than 0.007, less than 0.006, or less than 0.005, and even more preferably less than 0.004 or less than 0.0035. The lower the lower limit of the dielectric tangent, the better, but it can usually be 0.001 or more.

The resin composition of the present invention can provide a cured product having excellent adhesion to a plated conductive layer (plating adhesion) and excellent adhesion to a base conductive layer (base adhesion). The plating adhesion of the cured product of the resin composition of the present invention can be measured by the method described in <Determination of Plating Adhesion> described later. Furthermore, the base adhesion of the cured product of the resin composition of the present invention can be measured by the method described in <Determination of Base Adhesion> described later. The plating adhesion of the obtained cured product, that is, the adhesion strength (peeling strength) to the plated conductive layer is preferably more than 0.40 kgf/cm. The base adhesion of the obtained cured product, that is, the adhesion strength (peel strength) with the base conductive layer is preferably more than 0.50 kgf/cm. The upper limit of the adhesion strength is not particularly limited, but is usually 1.2 kgf/cm or less.

The resin composition of the present invention can provide a cured product with low dielectric tangent and excellent coating adhesion and substrate adhesion. Accordingly, the resin composition of the present invention can be used as a resin composition for forming an insulating layer (resin composition for forming an insulating layer of a conductive layer) in contact with the conductive layer (including a redistribution layer). Furthermore, the resin composition of the present invention can be suitably used as a resin composition for forming an insulating layer of a printed wiring board (resin composition for forming an insulating layer of a printed wiring board), and can be suitably used as a resin composition for forming an interlayer insulating layer of a printed wiring board (resin composition for forming an interlayer insulating layer of a printed wiring board). Furthermore, the resin composition of the present invention can be suitably used as a resin composition for embedding semiconductor parts in a semiconductor package, or for embedding parts in a circuit board with built-in parts (resin composition for embedding parts). The resin composition of the present invention can be used in a wide range of applications such as sheet-shaped laminate materials such as bonding films and prepregs, solder resists, underfill materials, chip bonding materials, and filling resins as required by resin compositions.

[Sheet-like laminate] The resin composition of the present invention can also be used by coating in a varnish state, but in general, it is suitable for use in the form of a sheet-like laminate containing the resin composition in industry.

As the sheet-shaped laminate material, the adhesive film and prepreg shown below are preferred.

In one embodiment, the bonding film comprises a support, and a resin composition layer (bonding layer) bonded to the support, and the resin composition layer (bonding layer) is formed of the resin composition of the present invention.

The thickness of the resin composition layer is preferably 100 μm or less, more preferably 80 μm or less, and even more preferably 60 μm or less or 50 μm or less from the viewpoint of thinning the printed wiring board. The lower limit of the thickness of the resin composition layer is not particularly limited, but is usually 1 μm or more, 5 μm or more, etc.

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

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

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

The surface of the support body on the side to be bonded to the resin composition layer may be subjected to matte treatment or corona treatment. In addition, as the support body, a support body with a release layer having a release layer on the surface of the side to be bonded to the resin composition layer may be used. As a release agent for the release layer of the support body with a release layer, for example, at least one release agent selected from the group consisting of alkyd resins, olefin resins, urethane resins and silicone resins may be listed. As commercially available products of the release agent, for example, alkyd resin-based release agents such as "SK-1", "AL-5", and "AL-7" manufactured by Lintec Co., Ltd. may be listed.

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

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

Examples of the organic solvent 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, and amide solvents such as dimethylformamide, dimethylacetamide (DMAc), and N-methylpyrrolidone. The organic solvent may be used alone or in combination of two or more.

Drying can be carried out by known methods such as heating and hot air blowing. Drying conditions are not particularly limited, but drying is performed in such a manner that the content of the organic solvent in the resin composition layer becomes 10 mass % or less, preferably 5 mass % or less. Although it varies depending on the boiling point of the organic solvent in the resin varnish, for example, when a resin varnish containing 30 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.

A protective film according to the support may be further laminated on the surface of the adhesive film that is not bonded to the support of the resin composition layer (i.e., the surface opposite to the support). The thickness of the protective film is not particularly limited, but is, for example, 1 μm to 40 μm. By laminating the protective film, it is possible to prevent dust and the like from adhering to or scratching the surface of the resin composition layer. The adhesive film may be stored in a roll. When the adhesive film has a protective film, it can be used by peeling off the protective film.

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

The sheet-like fiber substrate used for the prepreg is not particularly limited, and glass cloth, aramid non-woven fabric, liquid crystal polymer non-woven fabric, etc., which are commonly used as prepreg substrates, can be used. From the viewpoint of thinning the printed wiring board, the thickness of the sheet-like fiber substrate is preferably 50 μm or less, more preferably 40 μm or less, further preferably 30 μm or less, and further preferably 20 μm or less. The lower limit of the thickness of the sheet-like fiber substrate is not particularly limited, but is usually 10 μm or more.

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

The thickness of the prepreg can be in the same range as that of the resin composition layer to which the film is attached.

In sheet laminating materials, the minimum melt viscosity of the resin composition layer varies according to the specific design of the printed wiring board (circuit thickness of the inner substrate, line/space ratio, cavity size for accommodating components when manufacturing a component-embedded circuit board, etc.), and the optimum value for achieving good circuit embedding and component embedding varies. Therefore, by manufacturing sheet laminating materials, the resin composition layer is designed in a manner that exhibits the expected minimum melt viscosity. However, with respect to sheet laminating materials using conventional resin compositions containing a curing accelerator, there are cases where the resin composition slowly hardens during storage to increase the viscosity, and when used in the manufacture of printed wiring boards, there are cases where a minimum melt viscosity significantly higher than the expected value is exhibited.

In contrast, the resin composition of the present invention in which the components (C) and (D) are mixed can achieve a cured product having a low dielectric tangent and excellent coating adhesion and substrate adhesion, and can also suppress the progress of curing of the resin composition during storage, thereby facilitating the maintenance of a desired minimum melt viscosity. In one embodiment, the sheet-like laminate material of the present invention is characterized in that the lowest melt viscosity of the resin composition layer just after manufacture is defined as V ₁ (poise), and the lowest melt viscosity of the resin composition layer after storage at room temperature (25°C) for 24 hours is defined as V ₂ (poise), and the ratio of V ₂ /V ₁ (hereinafter also referred to as "viscosity increase ratio") is preferably 2 or less, more preferably 1.8 or less, further preferably 1.6 or less, still further preferably 1.5 or less, particularly preferably 1.4 or less, 1.3 or less, 1.2 or less, or 1.1 or less. The lower limit of the viscosity increase ratio is preferably 1.

Here, the so-called "minimum melt viscosity" of the resin composition layer refers to the minimum viscosity of the resin composition layer when the resin of the resin composition layer is melted. In detail, when the resin composition layer is heated at a certain heating rate to melt the resin, the melt viscosity decreases as the temperature rises in the initial stage, and then, when it exceeds a certain temperature, the melt viscosity increases as the temperature rises. The so-called "minimum melt viscosity" refers to the melt viscosity of this extremely small point. The minimum melt viscosity of the resin composition layer can be measured by the method described in <Measurement of Minimum Melt Viscosity> described later. Specifically, the minimum melt viscosity of the resin composition layer can be obtained by performing a dynamic viscoelasticity measurement under the conditions of a measurement start temperature of 60°C, a temperature rise rate of 5°C/min, a vibration rate of 1 Hz, and a stress of 1 degree. An example of a dynamic viscoelasticity measurement device is "Rheosol-G3000" manufactured by UBM Corporation.

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

In one embodiment, the printed wiring board of the present invention can be manufactured by using the above-mentioned bonding film, comprising the following steps (I) and (II). (I) A step of laminating the bonding film on the inner substrate in such a manner that the resin composition layer of the bonding film is bonded to the inner substrate (II) A step of thermally curing the resin composition layer to form an insulating layer

The so-called "inner layer substrate" used in step (I) mainly refers to a substrate such as a glass epoxy substrate, a metal substrate, a polyester substrate, a polyimide substrate, a BT resin substrate, a thermosetting polyphenylene ether substrate, or a circuit substrate having a conductive layer (circuit) patterned on one or both sides of the substrate. In addition, when manufacturing a printed wiring board, an inner layer circuit substrate of an intermediate product on which an insulating layer and/or a conductive layer is to be formed is also included in the so-called "inner layer substrate" of the present invention. When the printed wiring board is a circuit board with built-in components, an inner layer substrate with built-in components can be used.

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

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

Lamination can be performed by a commercially available vacuum laminating press. Examples of commercially available vacuum laminating presses include a vacuum press manufactured by Mingji Manufacturing Co., Ltd. and a vacuum appliquer manufactured by Nikko-Materials Co., Ltd.

After lamination, the laminated film can be smoothed by, for example, pressing a heat-pressing member from the support side under normal pressure (atmospheric pressure). The pressing conditions for the smoothing treatment can be the same as the heat-pressing conditions for the lamination described above. The smoothing treatment can be performed by a commercially available laminating press. In addition, the lamination and smoothing treatment can be performed continuously using the commercially available vacuum laminating press described above.

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

In step (II), the resin composition layer is thermally hardened to form an insulating layer.

The heat curing conditions of the resin composition layer are not particularly limited, and the conditions generally used when forming an insulating layer of a printed wiring board can be used.

For example, although the heat curing conditions of the resin composition layer vary depending on the type of the resin composition, the curing temperature can be set in the range of 120°C to 240°C (preferably in the range of 150°C to 220°C, and more preferably in the range of 170°C to 200°C), and the curing time can be set in the range of 5 minutes to 120 minutes (preferably 10 minutes to 100 minutes, and more preferably 15 minutes to 90 minutes).

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

When manufacturing a printed wiring board, the steps (III) of drilling holes in the insulating layer, (IV) of roughening the insulating layer, and (V) of forming a conductive layer on the surface of the insulating layer may be further performed. These steps (III) to (V) are used in the manufacture of printed wiring boards, and can be performed by a person having ordinary knowledge in the field of the present invention according to various known methods. In addition, when the support is removed after step (II), the removal of the support may be performed between step (II) and step (III), between step (III) and step (IV), or between step (IV) and step (V).

In other embodiments, the printed wiring board of the present invention can be manufactured using the above-mentioned prepreg. The manufacturing method is basically the same as that of the case where the bonding film is used.

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

Step (IV) is a step of roughening the insulating layer. The order and conditions of the roughening treatment are not particularly limited, and the known order and conditions commonly used when forming the insulating layer of the printed wiring board can be adopted. For example, swelling treatment by swelling liquid, roughening treatment by oxidizing agent, and neutralization treatment by neutralizing liquid can be carried out in this order to roughen the insulating layer. The swelling liquid is not particularly limited, but alkaline solution, surfactant solution, etc. can be listed, preferably alkaline solution, and as the alkaline solution, sodium hydroxide solution and potassium hydroxide solution are more preferably used. Examples of commercially available swelling liquids include "Swelling Dip Securiganth P" and "Swelling Dip Securiganth SBU" manufactured by Atotech Japan Co., Ltd. The swelling treatment with the swelling liquid is not particularly limited, but for example, the insulating layer may be immersed in a swelling liquid at 30°C to 90°C for 1 to 20 minutes. From the viewpoint of suppressing the swelling of the resin of the insulating layer to an appropriate level, it is preferred to immerse the cured body in a swelling liquid at 40°C to 80°C for 5 to 15 minutes. Although not particularly limited, examples of the oxidizing agent include alkaline permanganic acid solutions in which potassium permanganate or sodium permanganate is dissolved in an aqueous solution of sodium hydroxide. The roughening treatment using the alkaline permanganic acid solution or the like with the oxidizing agent is preferably performed by immersing the insulating layer in the oxidizing agent solution heated to 60°C to 80°C for 10 to 30 minutes. In addition, the concentration of the permanganate salt in the alkaline permanganic acid solution is preferably 5% by mass to 10% by mass. Examples of commercially available oxidizing agents include alkaline permanganic acid solutions such as "Concentrate Compact CP" and "Reduction solution Securiganth P" manufactured by Atotech Japan Co., Ltd. In addition, as a neutralizing solution, an acidic aqueous solution is preferred, and as a commercial product, for example, "Reduction solution･Securigant P" manufactured by Atotech Japan (Co., Ltd.) can be listed. Treatment with a neutralizing solution can be performed by immersing the surface treated by roughening treatment with an oxidizing agent in a neutralizing solution at 30°C to 80°C for 5 minutes to 30 minutes. From the perspective of workability, etc., it is preferred to immerse the object treated by roughening treatment with an oxidizing agent in a neutralizing solution at 40°C to 70°C for 5 minutes to 20 minutes.

Step (V) is a step of forming a conductive layer.

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

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

The thickness of the conductor layer 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 plating. For example, the surface of the insulating layer can be plated by a conventionally known technique such as a semi-additive method or a fully additive method to form a conductive layer having a desired wiring pattern.

In other embodiments, the conductive layer may be formed using a metal foil. When the conductive layer is formed using a metal foil, step (V) is preferably performed between step (I) and step (II). For example, after step (I), the support is removed and the metal foil is layered on the surface of the exposed resin composition layer. The lamination of the resin composition layer and the metal foil may be performed by vacuum lamination. The lamination conditions may be the same as those described for step (I). Next, step (II) is performed to form an insulating layer. Then, the metal foil on the insulating layer can be used to form a conductive layer having a desired wiring pattern by using conventionally known techniques such as a subtractive method and a modified semi-additive method.

Metal foil can be produced by a known method such as electrolysis or rolling. Examples of commercially available metal foil include HLP foil and JXUT-III foil manufactured by JX Nippon Mining & Metal Co., Ltd., and 3EC-III foil and TP-III foil manufactured by Mitsui Mining & Metals Co., Ltd.

When a printed wiring board is manufactured using the resin composition of the present invention comprising a specific combination of component (C) and component (D), an insulating layer having a low dielectric tangent and excellent coating adhesion and substrate adhesion can be realized.

[Semiconductor package] The semiconductor package of the present invention includes a circuit substrate, a semiconductor component mounted on the circuit substrate, and a sealing material embedded (sealed) in the semiconductor component. The semiconductor package of the present invention is characterized in that the sealing material is formed by a cured product of the resin composition of the present invention. Here, the structure and type of the circuit substrate and semiconductor component constituting the semiconductor package of the present invention are not particularly limited, and any circuit substrate and semiconductor component commonly used in forming a semiconductor package can be used.

The semiconductor package of the present invention can be manufactured by embedding (sealing) a semiconductor part with the resin composition of the present invention. The conditions for sealing the semiconductor are not particularly limited, and any sealing conditions commonly used in manufacturing semiconductor packages can be adopted.

[Semiconductor device] The semiconductor device of the present invention is a hardened product containing the resin composition of the present invention. The semiconductor device of the present invention can be manufactured using the printed wiring board or semiconductor package of the present invention.

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

The following is a detailed description of the present invention by way of example. However, the present invention is not limited to the following example. In the following description, "parts" and "%" indicating amounts refer to "parts by mass" and "% by mass" respectively unless otherwise specified.

First, the measurement and evaluation methods of the physical properties in this manual are explained.

<Preparation of samples for evaluation of cured properties> The adhesive films obtained in the examples and comparative examples were thermally cured at 200°C for 90 minutes, and the support was peeled off to prepare sheet-shaped samples for evaluation of cured products.

<Measurement of dielectric tangent> A test piece with a width of 2 mm and a length of 80 mm was cut out from the sample for evaluation of curing properties. The test piece was measured for dielectric tangent at a measurement frequency of 5.8 GHz and a measurement temperature of 23°C using the measurement device "HP8362B" manufactured by Agilent Technologies by cavity resonance spectroscopy. A dielectric tangent of 0.0035 or less was evaluated as "0" (good), a dielectric tangent exceeding 0.0035 and below 0.0040 was evaluated as "△" (acceptable), and a dielectric tangent exceeding 0.0040 was evaluated as "×" (bad).

<Evaluation of substrate conditioning> (1) Base treatment of inner circuit substrate Both sides of the glass cloth-based epoxy resin copper-clad laminate (copper foil thickness 18μm, substrate thickness 0.4mm, Panasonic (R1515A)) forming the inner circuit were immersed in a micro-etchant (MEC (CZ8101)) and etched 1μm to roughen the copper surface.

(2) Lamination of adhesive film The adhesive film produced in the embodiment and the comparative example was laminated on both sides of the inner circuit substrate using a batch vacuum pressure laminating press ("MVLP-500" manufactured by Meiki Manufacturing Co., Ltd.) in such a way that the resin composition layer was bonded to the inner circuit substrate. Lamination was performed by reducing the pressure for 30 seconds to set the air pressure to below 13 hPa, and then pressing at 100°C and a pressure of 0.74 MPa for 30 seconds.

(3) Curing of the resin composition layer The laminated adhesive film is heat-cured at 200°C for 90 minutes to form a hardened material (insulating layer) on both sides of the inner circuit substrate. Then, the support is peeled off from the adhesive film.

(4) Roughening treatment The inner circuit substrate with the insulating layer formed was immersed in a swelling solution (Atotech Japan (stock) "Swelling Dip Securiganth P", a sodium hydroxide aqueous solution containing diethylene glycol monobutyl ether) at 60°C for 10 minutes, then immersed in a roughening solution (Atotech Japan (stock) "Concentrate Compact P", a 60g/L potassium permanganate, 40g/L sodium hydroxide aqueous solution) at 80°C for 20 minutes, and finally immersed in a neutralizing solution (Atotech Japan (stock) "Reduction solution Securigant P", a hydroxylamine sulfate aqueous solution) at 40°C for 5 minutes. Then, it was dried at 80°C for 30 minutes. The resulting substrate is called "evaluation substrate A".

(5) Formation of the plated conductive layer A plated conductive layer (second conductive layer) is formed on the surface of the evaluation substrate A according to the semi-additive method. Specifically, the evaluation substrate A is immersed in an electroless plating solution containing _PdCl2 at 40°C for 5 minutes, and then immersed in an electroless copper plating solution at 25°C for 20 minutes. The obtained evaluation substrate A is heated at 150°C for 30 minutes, annealed, and then electrolytically plated with copper sulfate to form a plated conductive layer with a thickness of 30μm. The evaluation substrate A with the plated conductive layer is annealed at 190°C for 60 minutes. The obtained substrate is referred to as "evaluation substrate B".

<Measurement of coating adhesion> In the coating conductor layer (second conductor layer) of the evaluation substrate B, a section with a width of 10 mm and a length of 100 mm was placed, and one end was peeled off and clamped with a clamp. At room temperature (25°C) at a speed of 50 mm/min, the load (kgf/cm (N/cm)) when 35 mm was peeled off in the vertical direction was measured. The measurement was performed using a tensile tester ("AC-50C-SL" manufactured by TSE). The case where the load exceeded 0.4 kgf/cm was evaluated as "○" (good), and the case where it was less than 0.4 kgf/cm was evaluated as "×" (bad).

<Determination of substrate adhesion> (1) Substrate treatment of copper foil The glossy surface of "3EC-III" (electric field copper foil, 35μm) manufactured by Mitsui Metal Mining Co., Ltd. was immersed in a micro-etching agent ("CZ8101" manufactured by MEC Co., Ltd.) to roughen the copper surface (Ra value = 1μm) and perform rust prevention treatment (CL8300). This copper foil is called CZ copper foil. It was then heated in an oven at 130°C for 30 minutes.

(2) Copper foil lamination and insulating layer formation The same operation as in "(2) Lamination of film" in the above <Preparation of evaluation substrate> was performed to prepare a substrate from which the support was peeled off. On the resin composition layer, the treated surface of the CZ copper foil of "3EC-III" was laminated under the same conditions as in "(2) Lamination of film" in the above <Preparation of evaluation substrate>. Furthermore, the resin composition layer was cured at 190°C for 90 minutes to form an insulating layer to prepare a sample.

(3) Measurement of copper foil peeling strength (base adhesion) The prepared sample was cut into small pieces of 150×30 mm. A cutter was used to insert a 10 mm wide and 100 mm long section into the copper foil portion of the small piece. One end of the peeled copper foil was clamped with a clamp ("AC-50C-SL" manufactured by TSE). The load when peeling 35 mm in the vertical direction was measured at a speed of 50 mm/min at room temperature using an Instron universal testing machine in accordance with JIS C6481. The load exceeding 0.5 kgf/cm was evaluated as "○" (good), and the load below 0.5 kgf/cm was evaluated as "×" (bad).

<Determination of minimum melt viscosity> For the resin composition layer connected to the film prepared in the embodiment and the comparative example, pellets for measurement (diameter 18 mm, 1.2-1.3 g) were prepared by compression using a mold. The melt viscosity of the obtained pellets for measurement was measured using a dynamic viscoelasticity measuring device ("Rheosol-G3000" manufactured by UBM). For the pellets for measurement, a parallel plate with a diameter of 18 mm was used to raise the temperature from a starting temperature of 60°C to 200°C at a heating rate of 5°C/min. The dynamic viscoelasticity was measured under the measurement conditions of a measurement temperature interval of 2.5°C, a vibration rate of 1 Hz, and a stress of 1 deg, and the minimum melt viscosity (poise) was calculated. For each resin composition layer, the initial minimum melt viscosity V ₁ (poise) immediately after film formation and the minimum melt viscosity V ₂ (poise) after storage at room temperature (25°C) for 24 hours were determined to calculate the viscosity increase ratio (V ₂ /V ₁ ). The viscosity increase ratio exceeding 2 was evaluated as "△", and the ratio below 2 was evaluated as "○".

<Example 1> 30 parts of bis(xylenol) epoxy resin ("YX4000HK" manufactured by Mitsubishi Chemical Co., Ltd., epoxy equivalent of about 185) were heated and dissolved in 30 parts of solvent naphtha while stirring, and then cooled to room temperature. 250 parts of spherical silica ("SO-C2" manufactured by Admatechs Co., Ltd., average particle size 0.5μm, carbon content per unit surface area 0.38mg/ ^m2 ) surface treated with an aminosilane coupling agent ("KBM573" manufactured by Shin-Etsu Chemical Co., Ltd.) were mixed and dispersed by three-roll kneading. 53.8 parts of active ester curing agent ("HPC-8000-65T" manufactured by DIC Corporation, a 65% toluene solution of non-volatile matter with an active group equivalent of about 223), 20 parts of acryl resin ("A-DOG" manufactured by Shin-Nakamura Chemical Industry Co., Ltd.), 10 parts of styrene resin ("OPE-2St 1200" manufactured by Mitsubishi Gas Chemical Co., Ltd., a 60% toluene solution of non-volatile matter), 5 parts of indole resin ("H-100" manufactured by Nippon Coating Chemical Co., Ltd.), 2 parts of 5% MEK solution of 4-dimethylaminopyridine (DMAP) as a curing accelerator, and diisopropylbenzene peroxide ("PERCUMYL D") 0.13 parts and 1,3-bis(diphenylphosphinopropane) ("DPPP" manufactured by Hokko Chemical Co., Ltd.) 1 part were uniformly dispersed with a rotary mixer to prepare resin varnish 1.

Next, on the release layer of the alkyd resin-based PET film ("AL-5" manufactured by Lintec, thickness 38μm), the resin varnish 1 was uniformly applied by a die coater in such a manner that the thickness of the resin composition layer after drying became 40μm, and then dried at 80-110°C (average 95°C) for 5 minutes to prepare a bonding film 1.

<Example 2> Except that the blending amount of 1,3-bis(diphenylphosphinopropane) ("DPPP" manufactured by Hokko Chemical Co., Ltd.) was changed from 1 part to 0.5 parts, the other procedures were the same as in Example 1 to prepare resin varnish 2 and adhesive film 2.

<Example 3> Except that the blending amount of 1,3-bis(diphenylphosphinopropane) ("DPPP" manufactured by Hokko Chemical Co., Ltd.) was changed from 1 part to 0.01 part, the other procedures were the same as in Example 1 to prepare resin varnish 3 and adhesive film 3.

<Example 4> Except that the blending amount of 1,3-bis(diphenylphosphinopropane) ("DPPP" manufactured by Hokko Chemical Co., Ltd.) was changed from 1 part to 10 parts, the other procedures were the same as in Example 1 to prepare resin varnish 4 and adhesive film 4.

<Example 5> Except that 1 part of 1,3-bis(diphenylphosphinopropane) ("DPPP" manufactured by Hokko Chemical Co., Ltd.) was replaced with 1 part of diphenylcyclohexylphosphine ("DPCP" manufactured by Hokko Chemical Co., Ltd.), the same procedures as in Example 1 were followed to prepare resin varnish 5 and adhesive film 5.

<Example 6> Except that 1 part of 1,3-bis(diphenylphosphinopropane) ("DPPP" manufactured by Hokko Chemical Co., Ltd.) was replaced with 1 part of 1,3-bis(diphenylphosphinobutane) ("DPBP" manufactured by Hokko Chemical Co., Ltd.), the same procedures as in Example 1 were followed to prepare resin varnish 6 and adhesive film 6.

<Example 7> Except that 1 part of 1,3-bis(diphenylphosphinopropane) ("DPPP" manufactured by Hokko Chemical Co., Ltd.) was replaced with 1 part of [4-(N,N-dimethylamino)phenyl]di-tert-butylphosphine ("Amphos" manufactured by Hokko Chemical Co., Ltd.), the other steps were the same as in Example 1 to prepare resin varnish 7 and adhesive film 7.

<Example 8> Except for changing the blending amount of 1,3-bis(diphenylphosphinopropane) ("DPPP" manufactured by Hokko Chemical Co., Ltd.) from 1 part to 15 parts, the same procedures as in Example 1 were followed to prepare resin varnish 8 and adhesive film 8.

<Comparative Example 1> Except that 1,3-bis(diphenylphosphinopropane) ("DPPP" manufactured by Hokko Chemical Co., Ltd.) was not mixed, the same procedures as in Example 1 were followed to prepare resin varnish 9 and adhesive film 9.

<Comparative Example 2> Except that 1 part of 1,3-bis(diphenylphosphinopropane) ("DPPP" manufactured by Hokko Chemical Co., Ltd.) was replaced with 1 part of triphenylphosphine ("TPPP" manufactured by Hokko Chemical Co., Ltd.), the same procedures as in Example 1 were followed to prepare a resin varnish 10 and a bonding film 10.

<Comparative Example 3> Except that 20 parts of a resin having an acryl group ("A-DOG" manufactured by Shin-Nakamura Chemical Industry Co., Ltd.) and 10 parts of a resin having a styrene group ("OPE-2St 1200" manufactured by Mitsubishi Gas Chemical Co., Ltd., a toluene solution with a non-volatile content of 60%) were not mixed, the same procedures as in Example 1 were followed to prepare a resin varnish 11 and an adhesive film 11.

The evaluation results of the embodiments and comparative examples are shown in Table 1.

Regarding the case where spherical silica "SO-C2" was not mixed, the case where a hardening accelerator (dimethylaminopyridine (DMAP) and "PERCUMYL D") was not mixed, and the case where indanecoumarone resin "H-100" was not mixed, although there were differences in degree, it was confirmed that they all returned to the same results as the above-mentioned examples.

Claims (18)

A resin composition comprises (A) an epoxy resin, (B) a hardener, (C) a resin having a free radical polymerizable unsaturated group, and (D) an aliphatic phosphine compound, wherein the free radical polymerizable unsaturated group of component (C) has one or more groups selected from the group consisting of an acryl group, a methacryl group, a styryl group, an alkenyl group, and a maleimide group, and component (D) is a compound represented by formula (D1) or formula (D2).

(In the formula, ^Rd1 and ^Rd2 are independently a hydrogen atom or a monovalent group represented by the formula: -(RO) _l -R', wherein l represents an integer of 0 to 5, R represents a divalent aromatic group which may have a substituent, or a divalent aliphatic group which may have a substituent, R' represents a monovalent aromatic group which may have a substituent, or a monovalent aliphatic group which may have a substituent, when R is present in plural numbers, they may be the same as or different from each other, at least one of ^Rd1 and ^Rd2 is a monovalent group represented by the formula: -(RO) _l -R', R (l=1 to 5) and R' (l=0) directly bonded to the phosphorus atom are a divalent aromatic group which may have a substituent, or a monovalent aromatic group which may have a substituent, respectively, and ^Rd3 is a formula: -(R"-O) _m -R''' represents a monovalent group, wherein m represents an integer of 0 to 5, R" represents a divalent aliphatic group which may have a substituent, R''' represents a monovalent aliphatic group which may have a substituent, and when R" exists in plural, they may be the same or different from each other)

(In the formula, ^Rd1 and ^Rd2 have the same meanings as above, L represents a divalent group represented by the formula: -(R"-O) _n -R"-, wherein n represents an integer of 0 to 5, R" has the same meaning as above, when R" exists in plural numbers, they may be the same as or different from each other, ^Rd4 and ^Rd5 each independently represent a hydrogen atom, a monovalent group represented by the formula: -(RO) _l -R' or a monovalent group represented by the formula: -LP( ^-Rd1 )(- ^Rd2 ), wherein l, R, R', L, ^Rd1 and ^Rd2 have the same meanings as above). The resin composition of claim 1, wherein the component (D) has 2 to 40 aliphatic carbon atoms in one molecule. The resin composition of claim 1, wherein, in formula (D1), i) either ^Rd1 or ^Rd2 is a monovalent group represented by the formula: -(RO) _l -R', where l is 0 and R' represents an aryl group which may have a substituent; ii) ^Rd3 is a monovalent group represented by the formula: -(R"-O) _m -R''', where m is an integer of 0 to 2, R" is an alkylene group which may have a substituent or a cycloalkylene group which may have a substituent, and R''' is an alkyl group which may have a substituent, an alkenyl group which may have a substituent or a cycloalkyl group which may have a substituent. The resin composition of claim 1, wherein, in formula (D1), i) ^Rd1 is a monovalent group represented by the formula: -(RO) _l -R', l is 0, and R' is an aryl group which may have a substituent, ii) ^Rd2 is a monovalent group represented by the formula: -(RO) _l -R', l is 0, and R' is an alkyl group which may have a substituent or an alkenyl group which may have a substituent, iii) ^Rd3 is a monovalent group represented by the formula: -(R"-O) _m -R''', m is an integer of 0 to 2, R" is an alkyl group which may have a substituent or a cycloalkyl group which may have a substituent, and R''' is an alkyl group which may have a substituent, an alkenyl group which may have a substituent, or a cycloalkyl group which may have a substituent. The resin composition of claim 1, wherein, in formula (D2), i) either ^Rd1 or ^Rd2 is a monovalent group represented by the formula: -(RO) _l -R', l is 0, and R' is an aryl group which may have a substituent; ii) L is a divalent group represented by the formula: -(R"-O) _n -R"-, n is an integer of 0 to 2, and R" is an alkylene group which may have a substituent or a cycloalkylene group which may have a substituent; iii) either ^Rd4 or ^Rd5 is a monovalent group represented by the formula: -(RO) _l -R', l is 0, and R' is an aryl group which may have a substituent. The resin composition of claim 1, wherein the component (D) comprises a compound represented by any one of the following formulae:

In the resin composition of claim 1, when the non-volatile components in the resin composition are taken as 100% by mass, the content of component (C) is 1% by mass or more and 20% by mass or less. In the resin composition of claim 1, when the resin component is taken as 100% by mass, the content of component (D) is 0.001% by mass to 10% by mass. The resin composition of claim 1, wherein component (A) comprises a biphenyl epoxy resin. The resin composition of claim 1, wherein component (B) comprises an active ester hardener. The resin composition of claim 1, wherein the number average molecular weight of component (C) is greater than 100 and less than 10,000. The resin composition of claim 1, wherein the component (C) is one or more selected from the group consisting of a compound represented by formula (C5), a compound represented by formula (C6), a compound represented by formula (C7), a compound represented by formula (C9) and a compound represented by formula (C10),

(In the formula, R ¹ to R ⁶ independently represent a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, at least one of a and b is not 0 but an integer between 0 and 100, B represents a divalent group represented by formula (C2-1), (C2-2) or (C2-3),

In formula (C2-1), R ¹⁵ to R ¹⁸ each independently represent a hydrogen atom, an alkyl group having 6 or less carbon atoms, or a phenyl group; in formula (C2-2), R ¹⁹ to R ²⁶ each independently represent a hydrogen atom, an alkyl group having 6 or less carbon atoms, or a phenyl group; in formula (C2-3), R ²⁷ to R ³⁴ each independently represent a hydrogen atom, an alkyl group having 6 or less carbon atoms, or a phenyl group; and E represents a linear, branched, or cyclic divalent hydrocarbon group having 20 or less carbon atoms.

(wherein, ring F represents a divalent group having a cyclic ether structure of 5 or more ring members, ^B1 and ^B2 each independently represent a single bond or a group consisting of two or more groups selected from the group consisting of an arylene group which may have a substituent and a group represented by -COO-, and ^C1 and ^C2 each independently represent a vinyl group, a methacryl group, an acryl group or a styryl group)

(where n represents 1~5). The resin composition of claim 1 further comprises (E) an inorganic filler. In the resin composition of claim 13, when the non-volatile components in the resin composition are taken as 100% by mass, the content of the (E) inorganic filler is 50% by mass or more. The resin composition of claim 1 is used to form an insulating layer of a conductive layer. A sheet-like laminate material, which contains a resin composition as described in any one of claims 1 to 15. A printed wiring board comprising an insulating layer formed of a cured product of a resin composition as described in any one of claims 1 to 15. A semiconductor device comprising a cured product of the resin composition of any one of claims 1 to 15.