Resin composition, prepreg, metal foil-clad laminated sheet, composite resin sheet, printed wiring board, and semiconductor device

Abstract

To provide a novel resin composition having excellent dielectric properties, and a prepreg, a metal foil-clad laminated sheet, a composite resin sheet, a printed wiring board, and a semiconductor device.SOLUTION: This resin composition contains: a polymer (A) having a constituent unit represented by formula (V); an inorganic filler (B) containing an organic group with a carbon-carbon unsaturated bond; and another thermosetting compound (C) that does not correspond to the polymer (A) or the inorganic filler (B). In formula (V), Ar denotes an aromatic hydrocarbon linking group. * denotes a bonding position.SELECTED DRAWING: None

Description

[Technical Field]

[0001] The present invention relates to a resin composition, a prepreg, a metal foil-clad laminate, a resin composite sheet, a printed wiring board, and a semiconductor device. [Background technology]

[0002] In recent years, there has been an accelerating trend toward higher integration and miniaturization of semiconductor elements used in mobile terminals, electronic devices, communication devices, etc. This has led to a demand for technology that enables high-density packaging of semiconductor elements, and there has also been a demand for improvements in printed wiring boards, which play an important role in this process. Meanwhile, the applications of electronic devices and other devices are becoming more diverse and expanding. Accordingly, the properties required of printed wiring boards and the metal foil-clad laminates and prepregs used therein are becoming more diverse and stricter. Taking these required properties into consideration, various materials and processing methods have been proposed to obtain improved printed wiring boards. One example of this is the development of improved resin materials that make up prepregs and resin composite sheets. For example, Patent Document 1 discloses a novel soluble polyfunctional vinyl aromatic copolymer having improved heat resistance, compatibility, transparency, and toughness, a method for producing the same, and a curable composition containing the copolymer. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] International Publication No. 2017 / 115813 Summary of the Invention [Problem to be solved by the invention]

[0004] As mentioned above, the applications of electronic devices and the like are diversifying and expanding, and new resin materials are being demanded for prepregs, etc. In particular, further development of resin compositions with excellent dielectric properties is required. The present invention aims to solve the above-mentioned problems, and aims to provide a novel resin composition having excellent dielectric properties, as well as a prepreg, a metal foil-clad laminate, a resin composite sheet, a printed wiring board, and a semiconductor device. [Means for solving the problem]

[0005] In view of the above-mentioned problems, the present inventors have conducted studies and found that the above-mentioned problems can be solved by blending a predetermined aromatic vinyl polymer with an inorganic filler containing an organic group having a carbon-carbon unsaturated bond. Specifically, the above problems were solved by the following means. <1> A resin composition comprising: a polymer (A) having a structural unit represented by formula (V); an inorganic filler (B) containing an organic group containing a carbon-carbon unsaturated bond; and another thermosetting compound (C) that does not fall under the category of the polymer (A) or the inorganic filler (B). [ka] (In formula (V), Ar represents an aromatic hydrocarbon linking group. * represents a bonding position.) <2> The weight average molecular weight of the polymer (A) is 1,000 to 160,000. <1> The resin composition according to claim 1. <3> the content of the polymer (A) is 5 to 70 parts by mass relative to 100 parts by mass of the resin solid content in the resin composition; <1> or <2> The resin composition according to claim 1. <4> the organic group containing a carbon-carbon unsaturated bond has a CH═C(X)— (X is a hydrogen atom or a methyl group) structure; <1> ~ <3> The resin composition according to any one of the above. <5> the organic group containing a carbon-carbon unsaturated bond contains at least one selected from the group consisting of a vinyl group, an allyl group, an acryl group, and a methacryl group; <1> ~ <4> The resin composition according to any one of the above. <6> The inorganic filler (B) is an inorganic filler in which the organic group containing a carbon-carbon unsaturated bond is bonded via a silicon atom. <1> ~ <5> The resin composition according to any one of the above. <7> The inorganic filler (B) contains one or more selected from the group consisting of silica, aluminum hydroxide, aluminum nitride, boron nitride, forsterite, titanium oxide, barium titanate, strontium titanate, and calcium titanate. <1> ~ <6> The resin composition according to any one of the above. <8> The inorganic filler (B) contains silica. <1> ~ <6> The resin composition according to any one of the above. <9> the inorganic filler (B) is obtained by reacting, in a slurry state, an organosilicon compound having an organic group containing a carbon-carbon unsaturated bond with silica; <1> ~ <6> The resin composition according to any one of the above. <10> the content of the inorganic filler (B) is 10 to 500 parts by mass relative to 100 parts by mass of the resin solid content in the resin composition; <1> ~ <9> The resin composition according to any one of the above. <11> the other thermosetting compound (C) includes at least one selected from the group consisting of maleimide compounds, polyphenylene ether compounds containing two or more carbon-carbon unsaturated double bonds, cyanate ester compounds, epoxy compounds, phenol compounds, alkenyl-substituted nadimide compounds, oxetane resins, and benzoxazine compounds; <1> ~ <10> The resin composition according to any one of the above. <12> the other thermosetting compound (C) comprises at least one selected from the group consisting of a compound (M1) represented by formula (M1), a compound represented by formula (M3), a compound represented by formula (M5), and a compound represented by formula (OP-1), <1> ~ <11> The resin composition according to any one of the above. [ka] (In formula (M1), R M1 , R M2 , R M3 , and R M4 R each independently represents a hydrogen atom or an organic group. M5 and R M6 each independently represents a hydrogen atom or an alkyl group. M represents a divalent aromatic group. A is a 4- to 6-membered alicyclic group. RM7 and R M8 are each independently an alkyl group. mx is 1 or 2, and lx is 0 or 1. R M9 and R M10 R each independently represents a hydrogen atom or an alkyl group. M11 , R M12 , R M13 , and R M14 R each independently represents a hydrogen atom or an organic group. M15 each independently represents an alkyl group having 1 to 10 carbon atoms, an alkyloxy group having 1 to 10 carbon atoms, an alkylthio group having 1 to 10 carbon atoms, an aryl group having 6 to 10 carbon atoms, an aryloxy group having 1 to 10 carbon atoms, an arylthio group having 1 to 10 carbon atoms, a halogen atom, a hydroxyl group, or a mercapto group. px represents an integer of 0 to 3. nx represents an integer of 1 to 20. [ka] (In formula (M3), R 55 each independently represents a hydrogen atom, an alkyl group having 1 to 8 carbon atoms, or a phenyl group, and n5 represents an integer of 1 or more and 10 or less. [ka] (In formula (M5), R 58 each independently represents a hydrogen atom, an alkyl group having 1 to 8 carbon atoms, or a phenyl group; R 59 each independently represents a hydrogen atom or a methyl group, and n6 represents an integer of 1 or greater. [ka] (In formula (OP-1), X represents an aromatic group, -(YO)n2- represents a polyphenylene ether structure, and R 1 , R 2 , and ,R 3 each independently represents a hydrogen atom, an alkyl group, an alkenyl group, or an alkynyl group, n1 represents an integer of 1 to 6, n2 represents an integer of 1 to 100, and n3 represents an integer of 2 to 4. <13> the other thermosetting compound (C) includes at least one selected from the group consisting of a compound (M1) represented by formula (M1), a compound represented by formula (M3), and a compound represented by formula (OP-1), <1> ~ <11> The resin composition according to any one of the above. [ka] (In formula (M1), R M1 , R M2 , R M3 , and R M4 R each independently represents a hydrogen atom or an organic group. M5 and R M6 each independently represents a hydrogen atom or an alkyl group. M represents a divalent aromatic group. A is a 4- to 6-membered alicyclic group. R M7 and R M8 are each independently an alkyl group. mx is 1 or 2, and lx is 0 or 1. R M9 and R M10 R each independently represents a hydrogen atom or an alkyl group. M11 , R M12 , R M13 , and R M14 R each independently represents a hydrogen atom or an organic group. M15 each independently represents an alkyl group having 1 to 10 carbon atoms, an alkyloxy group having 1 to 10 carbon atoms, an alkylthio group having 1 to 10 carbon atoms, an aryl group having 6 to 10 carbon atoms, an aryloxy group having 1 to 10 carbon atoms, an arylthio group having 1 to 10 carbon atoms, a halogen atom, a hydroxyl group, or a mercapto group. px represents an integer of 0 to 3. nx represents an integer of 1 to 20. [ka] (In formula (M3), R 55 each independently represents a hydrogen atom, an alkyl group having 1 to 8 carbon atoms, or a phenyl group, and n5 represents an integer of 1 or more and 10 or less. [ka] (In formula (OP-1), X represents an aromatic group, -(YO)n2- represents a polyphenylene ether structure, and R 1 , R 2 , and ,R 3 each independently represents a hydrogen atom, an alkyl group, an alkenyl group, or an alkynyl group, n1 represents an integer of 1 to 6, n2 represents an integer of 1 to 100, and n3 represents an integer of 2 to 4. <14> the content of the thermosetting compound (C) is 5 to 95 parts by mass relative to 100 parts by mass of the resin solid content in the resin composition; <1> ~ <13> The resin composition according to any one of the above. <15> Relative to 100 parts by mass of resin solid content in the resin composition the content of the polymer (A) is 5 to 70 parts by mass, The content of the inorganic filler (B) is the content of the thermosetting compound (C) is 10 to 500 parts by mass, and the content of the thermosetting compound (C) is 5 to 95 parts by mass; <1> ~ <14> The resin composition according to any one of the above. <16> The weight average molecular weight of the polymer (A) is 1,000 to 160,000, the content of the polymer (A) is 5 to 70 parts by mass relative to 100 parts by mass of a resin solid content in the resin composition, the organic group containing a carbon-carbon unsaturated bond contains at least one selected from the group consisting of a vinyl group, an allyl group, an acrylic group, and a methacrylic group; the inorganic filler (B) is an inorganic filler in which the organic group containing a carbon-carbon unsaturated bond is bonded via a silicon atom, The inorganic filler (B) contains silica, the content of the inorganic filler (B) is 10 to 500 parts by mass relative to 100 parts by mass of a resin solid content in the resin composition; the other thermosetting compound (C) comprises at least one selected from the group consisting of maleimide compounds, polyphenylene ether compounds containing two or more carbon-carbon unsaturated double bonds, cyanate ester compounds, epoxy compounds, phenol compounds, alkenyl-substituted nadimide compounds, oxetane resins, and benzoxazine compounds; The content of the thermosetting compound (C) is 5 to 95 parts by mass relative to 100 parts by mass of resin solid content in the resin composition. <1> The resin composition according to claim 1. <17> The weight average molecular weight of the polymer (A) is 1,000 to 160,000, the content of the polymer (A) is 5 to 70 parts by mass relative to 100 parts by mass of a resin solid content in the resin composition, the organic group containing a carbon-carbon unsaturated bond contains at least one selected from the group consisting of a vinyl group, an allyl group, an acrylic group, and a methacrylic group; the inorganic filler (B) is an inorganic filler in which the organic group containing a carbon-carbon unsaturated bond is bonded via a silicon atom, the content of the inorganic filler (B) is 10 to 500 parts by mass relative to 100 parts by mass of a resin solid content in the resin composition; the inorganic filler (B) is obtained by reacting, in a slurry state, an organosilicon compound having an organic group containing a carbon-carbon unsaturated bond with silica; the other thermosetting compound (C) comprises at least one selected from the group consisting of a compound (M1) represented by formula (M1), a compound represented by formula (M3), a compound represented by formula (M5), and a compound represented by formula (OP-1), The content of the thermosetting compound (C) is 5 to 95 parts by mass relative to 100 parts by mass of resin solid content in the resin composition. <1> The resin composition according to claim 1. [ka] (In formula (M1), R M1 , R M2 , R M3 , and R M4 R each independently represents a hydrogen atom or an organic group. M5 and R M6 each independently represents a hydrogen atom or an alkyl group. M represents a divalent aromatic group. A is a 4- to 6-membered alicyclic group. R M7 and R M8are each independently an alkyl group. mx is 1 or 2, and lx is 0 or 1. R M9 and R M10 R each independently represents a hydrogen atom or an alkyl group. M11 , R M12 , R M13 , and R M14 R each independently represents a hydrogen atom or an organic group. M15 each independently represents an alkyl group having 1 to 10 carbon atoms, an alkyloxy group having 1 to 10 carbon atoms, an alkylthio group having 1 to 10 carbon atoms, an aryl group having 6 to 10 carbon atoms, an aryloxy group having 1 to 10 carbon atoms, an arylthio group having 1 to 10 carbon atoms, a halogen atom, a hydroxyl group, or a mercapto group. px represents an integer of 0 to 3. nx represents an integer of 1 to 20. [ka] (In formula (M3), R 55 each independently represents a hydrogen atom, an alkyl group having 1 to 8 carbon atoms, or a phenyl group, and n5 represents an integer of 1 or more and 10 or less. [ka] (In formula (M5), R 58 each independently represents a hydrogen atom, an alkyl group having 1 to 8 carbon atoms, or a phenyl group; R 59 each independently represents a hydrogen atom or a methyl group, and n6 represents an integer of 1 or greater. [ka] (In formula (OP-1), X represents an aromatic group, -(YO)n2- represents a polyphenylene ether structure, and R 1 , R 2 , and ,R 3 each independently represents a hydrogen atom, an alkyl group, an alkenyl group, or an alkynyl group, n1 represents an integer of 1 to 6, n2 represents an integer of 1 to 100, and n3 represents an integer of 2 to 4. <18> A substrate; <1> ~ <17> and a prepreg formed from the resin composition according to any one of the above. <19> <18> 1. A metal foil-clad laminate comprising: at least one layer formed from the prepreg according to claim 1; and metal foil disposed on one or both sides of the layer formed from the prepreg. <20> a support and a substrate disposed on the surface of the support <1> ~ <17> and a layer formed from the resin composition according to any one of the above. <21> A printed wiring board including an insulating layer and a conductor layer disposed on a surface of the insulating layer, wherein the insulating layer: <1> ~ <17> A printed wiring board comprising a layer formed from the resin composition according to any one of the above items. <22> <21> A semiconductor device comprising the printed wiring board according to claim 1. [Effects of the Invention]

[0006] The present invention makes it possible to provide a novel resin composition having excellent dielectric properties, as well as a prepreg, a metal foil-clad laminate, a resin composite sheet, a printed wiring board, and a semiconductor device. DETAILED DESCRIPTION OF THE INVENTION

[0007] Hereinafter, an embodiment for carrying out the present invention (hereinafter simply referred to as "the present embodiment") will be described in detail. Note that the present embodiment is an example for explaining the present invention, and the present invention is not limited to only this embodiment. In this specification, the symbol "to" is used to mean that the numerical values ​​before and after it are included as the lower limit and upper limit. In this specification, various physical properties and characteristic values ​​are those at 23°C unless otherwise specified. In the description of groups (atomic groups) in this specification, when a notation does not specify whether they are substituted or unsubstituted, it includes both groups (atomic groups) that have no substituents and groups (atomic groups) that have substituents. For example, the term "alkyl group" includes not only alkyl groups that have no substituents (unsubstituted alkyl groups) but also alkyl groups that have substituents (substituted alkyl groups). In this specification, when a notation does not specify whether they are substituted or unsubstituted, it is preferable that they be unsubstituted. In this specification, the relative dielectric constant refers to the ratio of the dielectric constant of a substance to the dielectric constant of a vacuum. Also, in this specification, the relative dielectric constant may be simply referred to as the "dielectric constant." In this specification, "(meth)acrylic" refers to both or either acrylic and methacrylic. If the standards shown in this specification differ depending on the year and the measurement method, etc., they will be based on the standards as of January 1, 2021, unless otherwise stated.

[0008] In this specification, the resin solids refer to the components excluding the inorganic filler (B) and the solvent, and include the polymer (A) having the structural unit represented by formula (V), as well as other thermosetting compounds (C) blended as necessary, elastomers, silane coupling agents, and other resin additive components (such as flame retardants). However, the surface treatment agent (such as a silane coupling agent) bonded to the inorganic filler (B) is included in the inorganic filler (B).

[0009] The resin composition of the present embodiment is characterized by comprising a polymer (A) having a structural unit represented by formula (V), an inorganic filler (B) containing an organic group containing a carbon-carbon unsaturated bond, and another thermosetting compound (C) that does not fall under the category of the polymer (A) or the inorganic filler (B). [ka] (In formula (V), Ar represents an aromatic hydrocarbon linking group. * represents a bonding position.) By using such a composition, a resin composition having excellent dielectric properties, particularly a low dielectric loss tangent, and excellent moisture absorption and heat resistance can be obtained. Inorganic fillers are known to improve the low thermal expansion properties of resin compositions. However, the surface of inorganic fillers typically contains functional groups, such as OH groups, that impair dielectric properties, and therefore, when used as is, the dielectric properties may be insufficient. Therefore, one method for improving the dielectric properties is to replace the functional groups on the surface of the inorganic filler with atomic groups (functional groups) that have excellent dielectric properties and compatibility with resins. In this embodiment, it has been discovered that by blending an inorganic filler (B) containing an organic group with a carbon-carbon unsaturated bond with a resin composition containing a polymer (A) having a structural unit represented by formula (V), it is possible to exhibit and maintain better dielectric properties. On the other hand, resin compositions containing a polymer (A) having a structural unit represented by formula (V) may not necessarily have sufficient dielectric properties and moisture-absorption heat resistance. For example, this may occur when the vinyl group equivalent weight of the polymer (A) having a structural unit represented by formula (V) contained in the resin composition is low. That is, when the vinyl group equivalent weight of the polymer (A) having a structural unit represented by formula (V) is low, the vinyl group content increases, and unreacted vinyl groups tend to remain when the resin composition is cured. It is believed that such unreacted vinyl groups may deteriorate the dielectric properties and moisture-absorption heat resistance. Furthermore, blending other components into the resin composition is considered as a method for lowering the dielectric properties and improving the moisture-absorption heat resistance of the cured resin composition. However, even when other components (especially resin components) are blended, the reduction of unreacted vinyl groups is often insufficient, which is believed to result in poor dielectric properties and moisture-absorption heat resistance. In this embodiment, it has been discovered that, under these circumstances, better dielectric properties can be exhibited by blending an inorganic filler (B) containing an organic group containing a carbon-carbon unsaturated bond with a resin composition containing a polymer (A) having a structural unit represented by formula (V). Furthermore, in this embodiment, it is presumed that by blending the inorganic filler (B) containing an organic group containing a carbon-carbon unsaturated bond, the organic group containing a carbon-carbon unsaturated bond reacts with the vinyl group in the polymer (A) having a structural unit represented by formula (V), thereby reducing the proportion of unreacted vinyl groups in the cured product and effectively suppressing deterioration of moisture absorption heat resistance.

[0010] <Polymer (A) Having a Structural Unit Represented by Formula (V)> The resin composition of the present embodiment contains a polymer (A) having a structural unit represented by formula (V). By containing the polymer (A) having a structural unit represented by formula (V), a resin composition having excellent low dielectric properties (low dielectric constant, low dielectric loss tangent) can be obtained. [ka] (In formula (V), Ar represents an aromatic hydrocarbon linking group. * represents a bonding position.) The aromatic hydrocarbon linking group may be a group consisting of only aromatic hydrocarbons which may have a substituent, or a group consisting of a combination of aromatic hydrocarbons which may have a substituent and other linking groups, and is preferably a group consisting of only aromatic hydrocarbons which may have a substituent. The substituent that the aromatic hydrocarbon may have includes a substituent Z (e.g., an alkyl group having 1 to 6 carbon atoms, an alkenyl group having 2 to 6 carbon atoms, an alkynyl group having 2 to 6 carbon atoms, an alkoxy group having 1 to 6 carbon atoms, a hydroxy group, an amino group, a carboxy group, a halogen atom, etc.). It is also preferable that the aromatic hydrocarbon does not have a substituent. The aromatic hydrocarbon linking group is usually a divalent linking group.

[0011] Specific examples of the aromatic hydrocarbon linking group include a phenylene group, a naphthalenediyl group, an anthracenediyl group, a phenanthrenediyl group, a biphenyldiyl group, and a fluorenediyl group, which may have a substituent, and among these, a phenylene group which may have a substituent is preferred. Examples of the substituent include the above-mentioned substituent Z, but it is preferable that the above-mentioned phenylene group and other groups have no substituent.

[0012] The structural unit represented by formula (V) more preferably includes at least one of a structural unit represented by the following formula (V1), a structural unit represented by the following formula (V2), and a structural unit represented by the following formula (V3). In the following formulae, * represents a bonding position. Furthermore, hereinafter, the structural units represented by formulas (V1) to (V3) may be collectively referred to as "structural unit (a)."

[0013] [ka] In formulas (V1) to (V3), L 1 is an aromatic hydrocarbon linking group (preferably having 6 to 22 carbon atoms, more preferably 6 to 18 carbon atoms, and even more preferably 6 to 10 carbon atoms). Specific examples include phenylene groups, naphthalenediyl groups, anthracenediyl groups, phenanthrenediyl groups, biphenyldiyl groups, and fluorenediyl groups, each of which may have a substituent, and among these, phenylene groups, which may have a substituent, are preferred. Examples of the substituent include the above-mentioned substituent Z, but it is preferable that the above-mentioned phenylene groups and other groups have no substituent. The compound forming the structural unit (a) is preferably a divinyl aromatic compound, such as divinylbenzene, bis(1-methylvinyl)benzene, divinylnaphthalene, divinylanthracene, divinylbiphenyl, and divinylphenanthrene. Among these, divinylbenzene is particularly preferred. These divinyl aromatic compounds may be used alone or in combination of two or more types, as required.

[0014] As described above, the polymer (A) having the structural unit represented by formula (V) may be a homopolymer of the structural unit (a), or may be a copolymer with a structural unit derived from another monomer. When the polymer (A) having the structural unit represented by formula (V) is a copolymer, the copolymerization ratio of the structural unit (a) is preferably 3 mol% or more, more preferably 5 mol% or more, even more preferably 10 mol% or more, and may be 15 mol% or more. The upper limit is preferably 90 mol% or less, more preferably 85 mol% or less, even more preferably 80 mol% or less, even more preferably 70 mol% or less, more preferably 60 mol% or less, even more preferably 50 mol% or less, even more preferably 40 mol% or less, particularly more preferably 30 mol% or less, and may even be 25 mol% or less, or 20 mol% or less.

[0015] An example of a structural unit derived from another monomer is a structural unit (b) derived from an aromatic compound having one vinyl group (monovinyl aromatic compound).

[0016] The structural unit (b) derived from a monovinyl aromatic compound is preferably a structural unit represented by the following formula (V4).

[0017] [ka] In formula (V4), L 2 is an aromatic hydrocarbon linking group, and specific examples of preferred groups include the above L 1 Examples include: R V1 is a hydrogen atom or a hydrocarbon group having 1 to 12 carbon atoms (preferably an alkyl group). V1 When R is a hydrocarbon group, it preferably has 1 to 6 carbon atoms, more preferably 1 to 3 carbon atoms. V1 and L 2 may have the above-mentioned substituent Z.

[0018] When the polymer (A) having a structural unit represented by formula (V) is a copolymer containing a structural unit (b) derived from a monovinyl aromatic compound, examples of the monovinyl aromatic compound include vinyl aromatic compounds such as styrene, vinylnaphthalene, and vinylbiphenyl; and nuclear alkyl-substituted vinyl aromatic compounds such as o-methylstyrene, m-methylstyrene, p-methylstyrene, o,p-dimethylstyrene, o-ethylvinylbenzene, m-ethylvinylbenzene, p-ethylvinylbenzene, methylvinylbiphenyl, and ethylvinylbiphenyl. The monovinyl aromatic compounds exemplified here may optionally have the above-mentioned substituent Z. Furthermore, these monovinyl aromatic compounds may be used alone or in combination of two or more.

[0019] When the polymer (A) having the structural unit represented by formula (V) is a copolymer containing the structural unit (b), the copolymerization ratio of the structural unit (b) is preferably 10 mol% or more, more preferably 15 mol% or more, and may even be 20 mol% or more, 30 mol% or more, 40 mol% or more, 50 mol% or more, 60 mol% or more, 70 mol% or more, or 75 mol% or more. The upper limit is preferably 98 mol% or less, more preferably 90 mol% or less, and even more preferably 85 mol% or less.

[0020] The polymer (A) having the structural unit represented by formula (V) may contain structural units other than the structural unit (a) and the structural unit (b). Examples of such structural units include structural units (c) derived from cycloolefin compounds. Examples of cycloolefin compounds include hydrocarbons having a double bond within the ring structure. Specific examples include monocyclic olefins such as cyclobutene, cyclopentene, cyclohexene, and cyclooctene, as well as compounds having a norbornene ring structure such as norbornene and dicyclopentadiene, and cycloolefin compounds having condensed aromatic rings such as indene and acenaphthylene. Examples of norbornene compounds include those described in paragraphs 0037 to 0043 of JP 2018-39995 A, the contents of which are incorporated herein by reference. The cycloolefin compounds exemplified here may further contain the aforementioned substituent Z.

[0021] When the polymer (A) having the structural unit represented by formula (V) is a copolymer containing the structural unit (c), the copolymerization ratio of the structural unit (c) is preferably 10 mol% or more, more preferably 20 mol% or more, and even more preferably 30 mol% or more. The upper limit is preferably 90 mol% or less, more preferably 80 mol% or less, and even more preferably 70 mol% or less, and may be 50 mol% or less, or may be 30 mol% or less.

[0022] The polymer (A) having the structural unit represented by formula (V) may further incorporate a structural unit (d) derived from a different polymerizable compound (hereinafter also referred to as "other polymerizable compound"). Examples of other polymerizable compounds (monomers) include compounds containing three vinyl groups. Specific examples include 1,3,5-trivinylbenzene, 1,3,5-trivinylnaphthalene, and 1,2,4-trivinylcyclohexane. Alternatively, examples include ethylene glycol diacrylate and butadiene. The copolymerization ratio of the structural unit (d) derived from other polymerizable compounds is preferably 30 mol% or less, more preferably 20 mol% or less, and even more preferably 10 mol% or less.

[0023] One embodiment of the polymer (A) having the structural unit represented by formula (V) is a polymer that essentially contains the structural unit (a) and includes at least one of the structural units (b) to (d). Further, an embodiment in which the total of the structural units (a) to (d) accounts for 95 mol % or more, and even 98 mol % or more, of all the structural units is exemplified. In another embodiment of the polymer (A) having a structural unit represented by formula (V), the structural unit (a) is essential, and of all structural units excluding the terminals, structural units containing an aromatic ring preferably account for 90 mol % or more, more preferably 95 mol % or more, and may even account for 100 mol %. In calculating the mole percentage per total structural units, one structural unit is defined as being derived from one molecule of a monomer (e.g., a divinyl aromatic compound, a monovinyl aromatic compound, etc.) used in the production of polymer (A) having a structural unit represented by formula (V).

[0024] The method for producing the polymer (A) having the structural unit represented by formula (V) is not particularly limited and may be a conventional method, for example, by polymerizing a raw material containing a divinyl aromatic compound (optionally in the presence of a monovinyl aromatic compound, a cycloolefin compound, etc.) in the presence of a Lewis acid catalyst. The Lewis acid catalyst may be a metal fluoride such as boron trifluoride or a complex thereof.

[0025] The structure of the chain end of the polymer (A) having the structural unit represented by formula (V) is not particularly limited, but in terms of the group derived from the above-mentioned divinyl aromatic compound, it may have the structure of the following formula (E1). 1 is the same as defined in the above formula (V1). * represents the bonding position. *-CH=CH-L 1 -CH=CH2(E1)

[0026] When a group derived from a monovinyl aromatic compound is at the chain end, the structure may be that of the following formula (E2): 2and R V1 are the same as defined in the formula (V4) above. * represents a bonding position. *-CH=CH-L 2 -R V1 (E2)

[0027] The molecular weight of the polymer (A) having a structural unit represented by formula (V) is preferably a number average molecular weight Mn of 300 or more, more preferably 500 or more, even more preferably 1,000 or more, and still more preferably 1,500 or more. The upper limit is preferably 130,000 or less, more preferably 120,000 or less, even more preferably 110,000 or less, and still more preferably 100,000 or less. The molecular weight (weight average molecular weight Mw) of the polymer (A) having the structural unit represented by formula (V) is preferably 1,000 or more, more preferably 1,500 or more, more preferably 2,000 or more, more preferably 2,500 or more, even more preferably 3,000 or more, and may be 3,500 or more or 4,000 or more. By setting the weight average molecular weight Mw at or above the lower limit, the excellent low dielectric properties of the polymer (A) having the structural unit represented by formula (V), particularly Df and dielectric properties after moisture absorption, can be effectively exhibited in the cured product of the resin composition. The upper limit is preferably 160,000 or less, more preferably 150,000 or less, even more preferably 140,000 or less, even more preferably 130,000 or less, and may be 120,000 or less, or 110,000 or less. Setting the weight average molecular weight Mw at or below the upper limit tends to reduce embedding defects when the prepreg or resin sheet is laminated on a circuit-printing substrate. The monodispersity (Mw / Mn), which is the ratio of the weight-average molecular weight Mw to the number-average molecular weight Mn, is preferably 100 or less, more preferably 50 or less, and even more preferably 20 or less. A practical lower limit is 1.1 or more, and may be 5 or more, 7 or more, or even 10 or more, which satisfies the required performance. The Mw and Mn are measured as described in the Examples below. When the resin composition of the present embodiment contains two or more polymers (A) having a structural unit represented by formula (V), it is preferable that the Mw, Mn and Mw / Mn of the mixture satisfy the above ranges.

[0028] The vinyl group equivalent of the polymer (A) having a structural unit represented by formula (V) is preferably 200 g / eq. or more, more preferably 230 g / eq. or more, even more preferably 250 g / eq. or more, and may be 300 g / eq. or more, or 350 g / eq. or more. The vinyl group equivalent is preferably 1200 g / eq. or less, more preferably 1000 g / eq. or less, and may further be 800 g / eq. or less, 600 g / eq. or less, 500 g / eq. or less, 400 g / eq. or less, or 350 g / eq. or less. By setting the equivalent at or above the lower limit, the storage stability of the resin composition tends to be improved, and the flowability of the resin composition tends to be improved. Therefore, moldability is improved, voids are less likely to occur during the formation of prepregs, etc., and more reliable printed wiring boards tend to be obtained. On the other hand, by setting the equivalent at or below the upper limit, the heat resistance of the resulting cured product tends to be improved.

[0029] Furthermore, the polymer (A) used in this embodiment having a structural unit represented by formula (V) preferably has excellent low dielectric properties when cured. For example, the cured polymer (A) used in this embodiment having a structural unit represented by formula (V) preferably has a relative dielectric constant (Dk) of 2.80 or less, more preferably 2.60 or less, even more preferably 2.50 or less, and even more preferably 2.40 or less, at 10 GHz, measured according to a cavity resonator perturbation method. Furthermore, a practical lower limit for the relative dielectric constant is, for example, 1.80 or more. Furthermore, the cured polymer (A) used in this embodiment having a structural unit represented by formula (V) preferably has a dielectric loss tangent (Df) of 0.0030 or less, more preferably 0.0020 or less, and even more preferably 0.0010 or less, at 10 GHz, measured according to a cavity resonator perturbation method. Furthermore, a practical lower limit for the dielectric loss tangent is, for example, 0.0001 or more. The relative permittivity (Dk) and the dielectric loss tangent (Df) are measured according to the method described in the examples below.

[0030] In this specification, for the polymer (A) having a structural unit represented by formula (V), compounds described in paragraphs 0029 to 0058 of International Publication No. 2017 / 115813 and their synthesis reaction conditions, etc., compounds described in paragraphs 0013 to 0058 of JP-A-2018-039995 and their synthesis reaction conditions, etc., compounds described in paragraphs 0008 to 0043 of JP-A-2018-168347 and their synthesis reaction conditions, etc., compounds described in paragraphs 0014 to 0042 of JP-A-2006-070136 and their synthesis reaction conditions, etc., compounds described in paragraphs 0014 to 0061 of JP-A-2006-089683 and their synthesis reaction conditions, etc., compounds described in paragraphs 0008 to 0036 of JP-A-2008-248001 and their synthesis reaction conditions, etc. can be referenced, and are incorporated herein by reference.

[0031] In the resin composition of this embodiment, the content of the polymer (A) having the structural unit represented by formula (V) is preferably 5 to 70 parts by mass, based on 100 parts by mass of the resin solid content in the resin composition. The lower limit of the content of the polymer (A) having the structural unit represented by formula (V), based on 100 parts by mass of the resin solid content in the resin composition, is more preferably 7 parts by mass or more, even more preferably 9 parts by mass or more, even more preferably 10 parts by mass or more, even more preferably 15 parts by mass or more, even more preferably 20 parts by mass or more, and particularly preferably 25 parts by mass or more. By ensuring that the content of the polymer (A) having the structural unit represented by formula (V) is at least the above-mentioned lower limit, low dielectric properties, in particular a low relative dielectric constant, can be effectively achieved. On the other hand, the upper limit of the content of polymer (A) having a structural unit represented by formula (V) is preferably 65 parts by mass or less, more preferably 60 parts by mass or less, even more preferably 50 parts by mass or less, even more preferably 40 parts by mass or less, and even more preferably 35 parts by mass or less, and may be 20 parts by mass or less, based on 100 parts by mass of the resin solid content in the resin composition. By keeping the content at or below the upper limit, the metal foil peel strength of the obtained cured product can be effectively increased. The resin composition may contain only one type of polymer (A) having a structural unit represented by formula (V), or two or more types. When two or more types are contained, it is preferable that the total amount is within the above range.

[0032] The resin composition of this embodiment may also be configured to be substantially free of aromatic divinyl compounds, particularly divinylbenzene. "Substantially free" means that the content of divinylbenzene and / or aromatic divinyl compounds is less than 1 part by mass, preferably less than 0.1 parts by mass, and more preferably less than 0.01 parts by mass, per 100 parts by mass of the resin solid content in the resin composition.

[0033] <Inorganic filler (B) containing an organic group containing a carbon-carbon unsaturated bond> The resin composition of this embodiment contains an inorganic filler (B) containing an organic group containing a carbon-carbon unsaturated bond. By including the inorganic filler (B) containing an organic group containing a carbon-carbon unsaturated bond, the dielectric properties of the resulting resin composition, and therefore of the prepreg, cured product, etc., can be further improved, particularly low dielectric tangent, flame resistance, and low thermal expansion. Furthermore, moisture absorption heat resistance can also be further improved.

[0034] Hereinafter, in the description of the inorganic filler (B) containing an organic group containing a carbon-carbon unsaturated bond, the compound containing the organic group containing a carbon-carbon unsaturated bond will be referred to as compound (b1), and the inorganic filler (B) without the organic group containing a carbon-carbon unsaturated bond will be referred to as inorganic filler (b2). An example of compound (b1) is a surface treatment agent for inorganic filler (b2). Therefore, examples of inorganic filler (b2) include inorganic fillers treated with a surface treatment agent other than compound (b1) and inorganic fillers that have not been treated with any surface treatment agent.

[0035] As described above, the inorganic filler (B) contains an organic group containing a carbon-carbon unsaturated bond. In this embodiment, the organic group containing a carbon-carbon unsaturated bond preferably has a CH═C(X)— (X is a hydrogen atom or a methyl group) structure, and more preferably contains at least one group selected from the group consisting of a vinyl group, an allyl group, an acrylic group, and a methacrylic group. Therefore, examples of the organic group containing a carbon-carbon unsaturated bond include a vinylsilyl group, an acrylsilyl group, a methacrylsilyl group, and a styrylsilyl group, with a vinylsilyl group being preferred.

[0036] The compound (b1) containing an organic group containing a carbon-carbon unsaturated bond is preferably liquid at 23° C. or soluble in a solvent. By using such a compound, the inorganic filler (b2) can be reacted with the compound (b1) containing an organic group containing a carbon-carbon unsaturated bond in a slurry containing the compound (b1) containing an organic group containing a carbon-carbon unsaturated bond and the inorganic filler (b2), and the inorganic filler (B) containing an organic group containing a carbon-carbon unsaturated bond can be suitably produced. Specific examples of the compound (b1) containing an organic group containing a carbon-carbon unsaturated bond include organic silicon compounds containing a carbon-carbon unsaturated bond, such as vinylsilanes (e.g., vinyltrimethoxysilane, vinyltriethoxysilane, etc.), acrylicsilanes (e.g., acrylictrimethoxysilane, acrylictriethoxysilane, etc.), methacrylicsilanes (e.g., methacrylictrimethoxysilane, methacrylictriethoxysilane, etc.), and styrylsilanes (e.g., styryltrimethoxysilane, styryltriethoxysilane, etc.). Among these, vinylsilanes are more preferred. The compound (b1) containing an organic group containing a carbon-carbon unsaturated bond may be used alone or in combination of two or more.

[0037] The content of compound (b1) in inorganic filler (B) containing an organic group containing a carbon-carbon unsaturated bond bonded to inorganic filler (b2) is preferably 0.1 parts by mass or more, more preferably 0.2 parts by mass or more, even more preferably 0.3 parts by mass or more, even more preferably 0.4 parts by mass or more, and even more preferably 0.5 parts by mass or more, relative to 100 parts by mass of inorganic filler (B). By setting the content at or above the lower limit, low dielectric properties and low water absorption tend to be further improved. Furthermore, the upper limit of the content of compound (b1) is preferably 10 parts by mass or less, more preferably 8 parts by mass or less, even more preferably 6 parts by mass or less, even more preferably 5 parts by mass or less, and even more preferably 4 parts by mass or less, relative to 100 parts by mass of inorganic filler (B). By setting the content at or below the upper limit, heat resistance tends to be improved. When two or more types of compound (b1) containing an organic group containing a carbon-carbon unsaturated bond are contained, the total amount thereof is preferably within the above range.

[0038] On the other hand, the inorganic filler (B) includes the inorganic filler (b2) as described above. The relative dielectric constant (Dk) of the inorganic filler (b2) measured according to the cavity resonator perturbation method is not limited. However, when a low relative dielectric constant is required, a lower relative dielectric constant (Dk) is preferable. In this embodiment, the relative dielectric constant (Dk) is preferably 8.0 or less, more preferably 6.0 or less, and even more preferably 4.0 or less. Furthermore, a practical lower limit of the relative dielectric constant is, for example, 2.0 or more. Furthermore, the inorganic filler (b2) used in this embodiment preferably has a dielectric loss tangent (Df) measured according to the cavity resonator perturbation method of 0.05 or less, more preferably 0.01 or less. Furthermore, a practical lower limit of the dielectric loss tangent is, for example, 0.0001 or more. The inorganic filler (b2) used in this embodiment is not particularly limited in type, and those generally used in the art can be suitably used. Specific examples include silicas such as natural silica, fused silica, synthetic silica, amorphous silica, aerosil, and hollow silica; metal oxides such as alumina, white carbon, titanium white, titanium oxide, zinc oxide, magnesium oxide, and zirconium oxide; composite oxides such as zinc borate, zinc stannate, forsterite, barium titanate, strontium titanate, and calcium titanate; nitrides such as boron nitride, aggregated boron nitride, silicon nitride, and aluminum nitride; aluminum hydroxide; and heat-treated aluminum hydroxide (aluminum hydroxide-treated products). Examples of suitable glass fibers include glass fibers that have been heat-treated and have had some of the water of crystallization removed), boehmite, metal hydroxides (including hydrates) such as magnesium hydroxide, molybdenum compounds such as molybdenum oxide and zinc molybdate, barium sulfate, clay, kaolin, talc, calcined clay, calcined kaolin, calcined talc, mica, E-glass, A-glass, NE-glass, C-glass, L-glass, D-glass, S-glass, M-glass G20, short glass fibers (including fine glass powders such as E-glass, T-glass, D-glass, S-glass, and Q-glass), hollow glass, and spherical glass. In this embodiment, the inorganic filler (b2) is preferably one or more selected from the group consisting of silica, aluminum hydroxide, aluminum nitride, boron nitride, forsterite, titanium oxide, barium titanate, strontium titanate, and calcium titanate, and when a low dielectric constant is required, it is more preferably one or more selected from the group consisting of silica and aluminum hydroxide, and even more preferably silica.

[0039] In this embodiment, the inorganic filler (B) can be obtained, for example, by bonding a compound (b1) containing an organic group containing a carbon-carbon unsaturated bond to the surface of an inorganic filler (b2). In this case, the compound (b1) containing an organic group containing a carbon-carbon unsaturated bond reacts with a functional group (preferably a hydroxyl group) on the surface of the inorganic filler (b2) to bond and become integrated. Furthermore, when the compound (b1) containing an organic group containing a carbon-carbon unsaturated bond and the inorganic filler (b2) are reacted in a liquid slurry, a portion of the compound (b1) may not be integrated and may remain as a free compound in the slurry. Specifically, as described above, it is preferable to react a compound (b1) (preferably an organosilicon compound) containing an organic group having a carbon-carbon unsaturated bond with an inorganic filler (b2) (preferably silica) in a slurry state. In this case, the number of functional groups in the compound (b1) containing an organic group having a carbon-carbon unsaturated bond (functional groups that react with the functional groups on the surface of the inorganic filler (b2), preferably the sum of hydroxyl groups and alkoxy groups) is preferably greater than the number of functional groups on the surface of the inorganic filler (b2) (functional groups that react with the compound (b1), preferably hydroxyl groups). Specifically, the number of functional groups in the compound (b1) is preferably 1 to 5 times, more preferably more than 1 to 5 times, the number of functional groups in the inorganic filler (b2). By reacting a compound (b1) having an excess number of functional groups with the inorganic filler (b2), the effects of the present invention tend to be more effectively achieved.

[0040] A preferred embodiment of the inorganic filler (B) is an inorganic filler in which the organic group containing a carbon-carbon unsaturated bond is bonded via a silicon atom, for example, when the compound (b1) containing an organic group containing a carbon-carbon unsaturated bond is an organosilicon compound.

[0041] The resin composition of this embodiment preferably contains an inorganic filler (B) and a compound (b1) containing an organic group containing a carbon-carbon unsaturated bond and not bonded to the inorganic filler (B). It is presumed that the presence of such a compound (b1) not bonded to the inorganic filler (B) more effectively caps the vinyl groups of the polymer (A), thereby more effectively exhibiting the effects of the present invention. For these reasons, in this embodiment, it is preferable to produce a resin composition by using the inorganic filler (B) produced using the compound (b1) in an amount such that the functional group equivalent in the slurry is in excess of the functional group equivalent on the surface of the inorganic filler (b2) without separating it from the slurry.

[0042] When the resin composition of this embodiment contains an inorganic filler (B) and a compound (b1) containing an organic group containing a carbon-carbon unsaturated bond and not bonded to the inorganic filler (B), the upper limit of the content of the compound (b1) is preferably 3 parts by mass or less, more preferably 2 parts by mass or less, even more preferably 1 part by mass or less, even more preferably 0.5 parts by mass or less, and even more preferably 0.2 parts by mass or less, per 100 parts by mass of the inorganic filler (B). By keeping the content below the upper limit, insulation reliability and low dielectric constant tend to be improved. The lower limit may be 0 parts by mass or more, but is preferably 0.0001 parts by mass or more. The resin composition of the present embodiment may contain only one compound (b1) containing an organic group containing a carbon-carbon unsaturated bond that is not bonded to the inorganic filler (B), or may contain two or more compounds (b1). When two or more compounds are contained, the total amount is preferably within the above range.

[0043] The content of the inorganic filler (B) in the resin composition of this embodiment is preferably 10 parts by mass or more, more preferably 20 parts by mass or more, even more preferably 40 parts by mass or more, even more preferably 60 parts by mass or more, and even more preferably 80 parts by mass or more, per 100 parts by mass of the resin solid content. By setting the content at or above the lower limit, the heat resistance and low thermal expansion properties of the resulting resin composition, prepreg, cured product, etc. tend to be further improved. Furthermore, the upper limit of the content of the inorganic filler (B) is preferably 500 parts by mass or less, more preferably 400 parts by mass or less, even more preferably 300 parts by mass or less, even more preferably 200 parts by mass or less, and may even be 150 parts by mass or less, per 100 parts by mass of the resin solid content. By setting the content at or below the upper limit, the formability of prepregs, etc., and the laminate formability of laminates, etc. tend to be further improved. In the resin composition of this embodiment, one preferred embodiment is one in which the content of the inorganic filler (B) is 30% by mass to 80% by mass of the components excluding the solvent. The resin composition of the present embodiment may contain only one type of inorganic filler (B), or may contain two or more types. When two or more types are contained, the total amount is preferably within the above range.

[0044] <Other thermosetting compounds (C)> The resin composition of the present embodiment preferably further contains another thermosetting compound (C) that does not fall under the category of the polymer (A) or the inorganic filler (B). By containing such a component, other desired performance required for the printed wiring board can be more effectively exhibited. In particular, in this embodiment, the weight-average molecular weight of the other thermosetting compound (C) is preferably 100 or more, more preferably 200 or more, and even more preferably 300 or more. The upper limit of the weight-average molecular weight of the other thermosetting compound (C) is preferably 5,000 or less, more preferably 4,000 or less. The functional group equivalent of the other thermosetting compound (C) is preferably 100 g / eq. or more, more preferably 150 g / eq. or more, and even more preferably 200 g / eq. or more. The upper limit of the functional group equivalent of the other thermosetting compound (C) is preferably 1,500 g / eq. or less, more preferably 1,300 g / eq. or less. In this embodiment, it is particularly preferred that the other thermosetting compound (C) satisfies the above-mentioned weight-average molecular weight and functional group equivalent weight. Such other thermosetting compound (C) tends to have a smaller weight-average molecular weight and a higher functional group concentration than the polymer (A) having the structural unit represented by formula (V), resulting in more crosslinking points and more effectively improving the moisture absorption heat resistance of the resulting cured product. In this embodiment, the composition preferably contains at least one selected from the group consisting of maleimide compounds, polyphenylene ether compounds containing two or more carbon-carbon unsaturated double bonds, cyanate ester compounds, epoxy compounds, phenol compounds, alkenyl-substituted nadimide compounds, oxetane resins, and benzoxazine compounds, more preferably contains a maleimide compound and / or a polyphenylene ether compound containing two or more carbon-carbon unsaturated double bonds, further preferably contains at least one selected from the group consisting of compounds (M1) represented by formula (M1), compounds represented by formula (M3), compounds represented by formula (M5), and compounds represented by formula (OP-1), and even more preferably contains at least one selected from the group consisting of compounds (M1) represented by formula (M3), and compounds represented by formula (OP-1). [ka] (In formula (M1), R M1 , R M2 , R M3 , and RM4 R each independently represents a hydrogen atom or an organic group. M5 and R M6 each independently represents a hydrogen atom or an alkyl group. M represents a divalent aromatic group. A is a 4- to 6-membered alicyclic group. R M7 and R M8 are each independently an alkyl group. mx is 1 or 2, and lx is 0 or 1. R M9 and R M10 R each independently represents a hydrogen atom or an alkyl group. M11 , R M12 , R M13 , and R M14 R each independently represents a hydrogen atom or an organic group. M15 each independently represents an alkyl group having 1 to 10 carbon atoms, an alkyloxy group having 1 to 10 carbon atoms, an alkylthio group having 1 to 10 carbon atoms, an aryl group having 6 to 10 carbon atoms, an aryloxy group having 1 to 10 carbon atoms, an arylthio group having 1 to 10 carbon atoms, a halogen atom, a hydroxyl group, or a mercapto group. px represents an integer of 0 to 3. nx represents an integer of 1 to 20. [ka] (In formula (M3), R 55 each independently represents a hydrogen atom, an alkyl group having 1 to 8 carbon atoms, or a phenyl group, and n5 represents an integer of 1 or more and 10 or less. [ka] (In formula (M5), R 58 each independently represents a hydrogen atom, an alkyl group having 1 to 8 carbon atoms, or a phenyl group; R 59 each independently represents a hydrogen atom or a methyl group, and n6 represents an integer of 1 or greater. [ka] (In formula (OP-1), X represents an aromatic group, -(YO)n2- represents a polyphenylene ether structure, and R 1 , R 2 , and ,R3 each independently represents a hydrogen atom, an alkyl group, an alkenyl group, or an alkynyl group, n1 represents an integer of 1 to 6, n2 represents an integer of 1 to 100, and n3 represents an integer of 2 to 4.

[0045] <<Maleimide compounds>> The resin composition of this embodiment may contain a maleimide compound. The resin composition of this embodiment is not particularly limited as long as it is a compound having one or more (preferably 2 to 12, more preferably 2 to 6, even more preferably 2 to 4, still more preferably 2 or 3, and still more preferably 2) maleimide groups in one molecule, and a wide variety of compounds commonly used in the field of printed wiring boards can be used. In this embodiment, compounds represented by formulas (M0) to (M5) are preferred, compounds represented by formulas (M1) to (M4) are more preferred, compounds represented by formulas (M1) and / or (M3) are even more preferred, and compound (M1) represented by formula (M1) is even more preferred. When these maleimide compounds are used in materials for printed wiring boards (e.g., metal foil-clad laminates), excellent heat resistance can be imparted. In particular, when compound (M1) represented by formula (M1) is used, low dielectric properties tend to be more effectively achieved. [ka] (In formula (M0), R 51 each independently represents a hydrogen atom, an alkyl group having 1 to 8 carbon atoms, or a phenyl group; R 52 each independently represents a hydrogen atom or a methyl group, and n1 represents an integer of 1 or greater. R 51 is preferably a hydrogen atom, a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a t-butyl group, an n-pentyl group, or a phenyl group, more preferably one of a hydrogen atom and a methyl group, and even more preferably a hydrogen atom. R 52 is preferably a methyl group. n1 is preferably an integer of 1 to 10, more preferably an integer of 1 to 5, even more preferably an integer of 1 to 3, still more preferably 1 or 2, and even more preferably 1. The compound represented by formula (M0) may be a single compound or a mixture of two or more compounds. Examples of the mixture include a mixture of compounds with different n1, 51 and / or R 52 Examples of such a mixture include a mixture of compounds having different types of substituents, a mixture of compounds having different bonding positions (meta, para, or ortho positions) of the maleimide group and oxygen atom relative to the benzene ring, and a mixture of compounds having a combination of two or more of the above differences. The same applies to the compounds represented by formulas (M1) to (M5) below. [ka] (In formula (M1), R M1 , R M2 , R M3 , and R M4 R each independently represents a hydrogen atom or an organic group. M5 and R M6 each independently represents a hydrogen atom or an alkyl group. M represents a divalent aromatic group. A is a 4- to 6-membered alicyclic group. R M7 and R M8 are each independently an alkyl group. mx is 1 or 2, and lx is 0 or 1. R M9 and R M10 R each independently represents a hydrogen atom or an alkyl group. M11 , R M12 , R M13 , and R M14 R each independently represents a hydrogen atom or an organic group. M15 each independently represents an alkyl group having 1 to 10 carbon atoms, an alkyloxy group having 1 to 10 carbon atoms, an alkylthio group having 1 to 10 carbon atoms, an aryl group having 6 to 10 carbon atoms, an aryloxy group having 1 to 10 carbon atoms, an arylthio group having 1 to 10 carbon atoms, a halogen atom, a hydroxyl group, or a mercapto group. px represents an integer of 0 to 3. nx represents an integer of 1 to 20.

[0046] R in the formula M1 , R M2 , R M3 , and R M4 R each independently represents a hydrogen atom or an organic group. The organic group here is preferably an alkyl group, more preferably an alkyl group having 1 to 12 carbon atoms, even more preferably an alkyl group having 1 to 6 carbon atoms, and even more preferably a methyl group, an ethyl group, a propyl group, or a butyl group, with a methyl group being particularly preferred. M1 and R M3 are each independently preferably an alkyl group, and R M2 and R M4 is preferably a hydrogen atom. R M5 and R M6 are each independently a hydrogen atom or an alkyl group, preferably an alkyl group. The alkyl group here is preferably an alkyl group having 1 to 12 carbon atoms, more preferably an alkyl group having 1 to 6 carbon atoms, further preferably a methyl group, an ethyl group, a propyl group, or a butyl group, and particularly preferably a methyl group. Ar M represents a divalent aromatic group, preferably a phenylene group, a naphthalenediyl group, a phenanthrenediyl group, or an anthracenediyl group, more preferably a phenylene group, and even more preferably an m-phenylene group. M may have a substituent, and the substituent is preferably an alkyl group, more preferably an alkyl group having 1 to 12 carbon atoms, even more preferably an alkyl group having 1 to 6 carbon atoms, still more preferably a methyl group, an ethyl group, a propyl group, or a butyl group, and particularly preferably a methyl group. M is preferably unsubstituted. A is a 4- to 6-membered alicyclic group, and more preferably a 5-membered alicyclic group (preferably a group that forms an indane ring when combined with a benzene ring). M7 and R M8 are each independently an alkyl group, preferably an alkyl group having 1 to 6 carbon atoms, more preferably an alkyl group having 1 to 3 carbon atoms, and particularly preferably a methyl group. mx is 1 or 2, and is preferably 2. lx is 0 or 1, and is preferably 1. R M9 and R M10 are each independently a hydrogen atom or an alkyl group, more preferably an alkyl group. The alkyl group here is preferably an alkyl group having 1 to 12 carbon atoms, more preferably an alkyl group having 1 to 6 carbon atoms, further preferably a methyl group, an ethyl group, a propyl group, or a butyl group, and particularly preferably a methyl group. R M11 , R M12 , R M13 , and R M14 R each independently represents a hydrogen atom or an organic group. The organic group here is preferably an alkyl group, more preferably an alkyl group having 1 to 12 carbon atoms, even more preferably an alkyl group having 1 to 6 carbon atoms, and even more preferably a methyl group, an ethyl group, a propyl group, or a butyl group, with a methyl group being particularly preferred. M12 and R M13 are each independently preferably an alkyl group, and R M11 and R M14 is preferably a hydrogen atom. R M15 each independently represents an alkyl group having 1 to 10 carbon atoms, an alkyloxy group having 1 to 10 carbon atoms, an alkylthio group having 1 to 10 carbon atoms, an aryl group having 6 to 10 carbon atoms, an aryloxy group having 1 to 10 carbon atoms, an arylthio group having 1 to 10 carbon atoms, a halogen atom, a hydroxyl group, or a mercapto group, and is preferably an alkyl group having 1 to 4 carbon atoms, a cycloalkyl group having 3 to 6 carbon atoms, or an aryl group having 6 to 10 carbon atoms. px represents an integer of 0 to 3, preferably an integer of 0 to 2, more preferably 0 or 1, and even more preferably 0. nx represents an integer of 1 to 20. nx may be an integer of 10 or less. The resin composition of this embodiment may contain only one compound (M1) represented by formula (M1) having at least one different value of nx, or may contain two or more compounds. When two or more compounds are contained, the average value of nx (average number of repeating units) n in the compound (M1) represented by formula (M1) in the resin composition is preferably 0.92 or more, more preferably 0.95 or more, even more preferably 1.0 or more, and even more preferably 1.1 or more, in order to achieve a low melting point (low softening point), low melt viscosity, and excellent handleability. Furthermore, n is preferably 10.0 or less, more preferably 8.0 or less, even more preferably 7.0 or less, even more preferably 6.0 or less, and may be 5.0 or less. The same applies to formula (M1-1) described below.

[0047] The compound (M1) represented by formula (M1) is preferably a compound represented by the following formula (M1-1). [ka] (In formula (M1-1), R M21 , R M22 , R M23 , and R M24 R each independently represents a hydrogen atom or an organic group. M25 and R M26 R each independently represents a hydrogen atom or an alkyl group. M27 , R M28 , R M29 , and R M30 R each independently represents a hydrogen atom or an organic group. M31 and R M32 R each independently represents a hydrogen atom or an alkyl group. M33 , R M34 , R M35 , and R M36 R each independently represents a hydrogen atom or an organic group. M37 , R M38 , and R M39 each independently represents a hydrogen atom or an alkyl group, and nx represents an integer of 1 or more and 20 or less.

[0048] R in the formula M21 , R M22 , R M23 , and R M24 R each independently represents a hydrogen atom or an organic group. The organic group here is preferably an alkyl group, more preferably an alkyl group having 1 to 12 carbon atoms, even more preferably an alkyl group having 1 to 6 carbon atoms, still more preferably a methyl group, an ethyl group, a propyl group, or a butyl group, and particularly preferably a methyl group. M21 and R M23 is preferably an alkyl group, and R M22 and R M24 is preferably a hydrogen atom. R M25 and R M26 are each independently a hydrogen atom or an alkyl group, preferably an alkyl group. The alkyl group here is preferably an alkyl group having 1 to 12 carbon atoms, more preferably an alkyl group having 1 to 6 carbon atoms, further preferably a methyl group, an ethyl group, a propyl group, or a butyl group, and particularly preferably a methyl group. R M27 , R M28 , R M29 , and R M30 each independently represents a hydrogen atom or an organic group, preferably a hydrogen atom. The organic group here is preferably an alkyl group, more preferably an alkyl group having 1 to 12 carbon atoms, even more preferably an alkyl group having 1 to 6 carbon atoms, still more preferably a methyl group, an ethyl group, a propyl group, or a butyl group, and particularly preferably a methyl group. R M31 and R M32 are each independently a hydrogen atom or an alkyl group, preferably an alkyl group. The alkyl group here is preferably an alkyl group having 1 to 12 carbon atoms, more preferably an alkyl group having 1 to 6 carbon atoms, further preferably a methyl group, an ethyl group, a propyl group, or a butyl group, and particularly preferably a methyl group. R M33 , R M34 , R M35 , and R M36each independently represents a hydrogen atom or an organic group. The organic group here is preferably an alkyl group, more preferably an alkyl group having 1 to 12 carbon atoms, even more preferably an alkyl group having 1 to 6 carbon atoms, still more preferably a methyl group, an ethyl group, a propyl group, or a butyl group, and particularly preferably a methyl group. R M33 and R M36 is preferably a hydrogen atom, and R M34 and R M35 is preferably an alkyl group. R M37 , R M38 , R M39 are each independently a hydrogen atom or an alkyl group, preferably an alkyl group. The alkyl group here is preferably an alkyl group having 1 to 12 carbon atoms, more preferably an alkyl group having 1 to 6 carbon atoms, further preferably a methyl group, an ethyl group, a propyl group, or a butyl group, and particularly preferably a methyl group. nx represents an integer of 1 or more and 20 or less. nx may be an integer of 10 or less.

[0049] The compound represented by formula (M1-1) is preferably a compound represented by the following formula (M1-2). [ka] (In formula (M1-2), R M21 , R M22 , R M23 , and R M24 R each independently represents a hydrogen atom or an organic group. M25 and R M26 R each independently represents a hydrogen atom or an alkyl group. M27 , R M28 , R M29 , and R M30 R each independently represents a hydrogen atom or an organic group. M31 and R M32 R each independently represents a hydrogen atom or an alkyl group. M33 , R M34 , R M35 , and R M36 R each independently represents a hydrogen atom or an organic group.M37 , R M38 , and R M39 each independently represents a hydrogen atom or an alkyl group, and nx represents an integer of 1 or more and 20 or less.

[0050] In formula (M1-2), R M21 , R M22 , R M23 , R M24 , R M25 , R M26 , R M27 , R M28 , R M29 , R M30 , R M31 , R M32 , R M33 , R M34 , R M35 , R M36 , R M37 , R M38 , R M39 , and nx are R in formula (M1-1), respectively. M21 , R M22 , R M23 , R M24 , R M25 , R M26 , R M27 , R M28 , R M29 , R M30 , R M31 , R M32 , R M33 , R M34 , R M35 , R M36 , R M37 , R M38 , R M39 , and nx, and the preferred ranges are also the same.

[0051] The compound represented by formula (M1-1) is preferably a compound represented by the following formula (M1-3), and more preferably a compound represented by the following formula (M1-4). [ka] (In formula (M1-3), nx represents an integer of 1 or more and 20 or less.) nx may be an integer of 10 or less. [ka] (In formula (M1-4), nx represents an integer of 1 or more and 20 or less.)

[0052] The molecular weight of the compound (M1) represented by formula (M1) is preferably 500 or more, more preferably 600 or more, and even more preferably 700 or more. By making the molecular weight equal to or greater than the lower limit, the low dielectric properties and low water absorption of the resulting cured product tend to be further improved. Furthermore, the molecular weight of the compound (M1) represented by formula (M1) is preferably 10,000 or less, more preferably 9,000 or less, even more preferably 7,000 or less, even more preferably 5,000 or less, and even more preferably 4,000 or less. By making the molecular weight equal to or less than the upper limit, the heat resistance and handleability of the resulting cured product tend to be further improved. [ka] (In formula (M2), R 54 each independently represents a hydrogen atom or a methyl group, and n4 represents an integer of 1 or greater. n4 is preferably an integer of 1 to 10, more preferably an integer of 1 to 5, even more preferably an integer of 1 to 3, and even more preferably 1 or 2. [ka] (In formula (M3), R 55 each independently represents a hydrogen atom, an alkyl group having 1 to 8 carbon atoms, or a phenyl group, and n5 represents an integer of 1 or more and 10 or less. R 55 is preferably a hydrogen atom, a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a t-butyl group, an n-pentyl group, or a phenyl group, more preferably one of a hydrogen atom and a methyl group, and even more preferably a hydrogen atom. n5 is preferably an integer of 1 or more and 5 or less, more preferably an integer of 1 to 3, and even more preferably 1 or 2. [ka] (In formula (M4), R 56 each independently represents a hydrogen atom, a methyl group, or an ethyl group; R 57 each independently represents a hydrogen atom or a methyl group.

[0053] [ka] (In formula (M5), R 58 each independently represents a hydrogen atom, an alkyl group having 1 to 8 carbon atoms, or a phenyl group; R 59 each independently represents a hydrogen atom or a methyl group, and n6 represents an integer of 1 or greater. R 58 is preferably a hydrogen atom, a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a t-butyl group, an n-pentyl group, or a phenyl group, more preferably one of a hydrogen atom and a methyl group, and even more preferably a hydrogen atom. R 59 is preferably a methyl group. n6 is preferably an integer of 1 to 10, more preferably an integer of 1 to 5, even more preferably an integer of 1 to 3, still more preferably 1 or 2, and may be 1. The compound represented by formula (M5) may be, and preferably is, a mixture of compounds in which n6 is different, or may be a mixture of compounds in which other moieties are different, as described for the compound represented by formula (M0).

[0054] The maleimide compound may be produced by a known method, or a commercially available product may be used. Examples of commercially available products include "BMI-80" manufactured by K.I. Chemical Industry Co., Ltd. as the compound represented by formula (M0), "NE-X-9470S" manufactured by DIC Corporation as the compound (M1) represented by formula (M1), "BMI-2300" manufactured by Daiwa Kasei Kogyo Co., Ltd. as the compound represented by formula (M2), "MIR-3000-70MT" manufactured by Nippon Kayaku Co., Ltd. as the compound represented by formula (M3), "BMI-70" manufactured by K.I. Chemical Industry Co., Ltd. as the compound represented by formula (M4), and "MIR-5000" manufactured by Nippon Kayaku Co., Ltd. as the compound represented by formula (M5).

[0055] Furthermore, examples of maleimide compounds other than those mentioned above include N-phenylmaleimide, phenylmethanemaleimide oligomers, m-phenylenebismaleimide, 2,2-bis(4-(4-maleimidophenoxy)-phenyl)propane, 4-methyl-1,3-phenylenebismaleimide, 1,6-bismaleimide-(2,2,4-trimethyl)hexane, 4,4'-diphenyletherbismaleimide, 4,4'-diphenylsulfonebismaleimide, 1,3-bis(3-maleimidophenoxy)benzene, 1,3-bis(4-maleimidophenoxy)benzene, prepolymers thereof, and prepolymers of these maleimides and amines.

[0056] When the resin composition of this embodiment contains a maleimide compound, the lower limit of the maleimide compound content is preferably 1 part by mass or more, more preferably 5 parts by mass or more, preferably 10 parts by mass or more, even more preferably 20 parts by mass or more, and even more preferably 25 parts by mass or more, per 100 parts by mass of the resin solid content in the resin composition. Having a maleimide compound content of 1 part by mass or more tends to improve the flame resistance of the resulting cured product. Furthermore, the upper limit of the maleimide compound content is preferably 70 parts by mass or less, more preferably 50 parts by mass or less, and may even be 40 parts by mass or less, per 100 parts by mass of the resin solid content in the resin composition. Having a maleimide compound content of 70 parts by mass or less tends to improve metal foil peel strength and low water absorbency. The resin composition of the present embodiment may contain only one maleimide compound or may contain two or more maleimide compounds. When two or more maleimide compounds are contained, the total amount is preferably in the above range. The resin composition of this embodiment may also be substantially free of maleimide compounds, particularly monofunctional maleimide compounds. "Substantially free" refers to the content of monofunctional maleimide compounds, or more specifically, maleimide compounds, being less than 1 part by mass, preferably less than 0.1 parts by mass, and more preferably less than 0.01 parts by mass, per 100 parts by mass of the resin solids in the resin composition. By being substantially free of monofunctional maleimides, the reaction between vinyl groups proceeds preferentially over the reaction between the maleimide groups of the maleimide compound and the vinyl groups of the polymer (A) having a structural unit represented by formula (V) or the inorganic filler (B), tending to produce a cured product with lower dielectric properties. Furthermore, when the reaction between vinyl groups proceeds preferentially, the degree of cure after heating tends to be improved from the standpoint of steric hindrance.

[0057] <<Polyphenylene ether compounds containing two or more carbon-carbon unsaturated double bonds>> The resin composition of the present embodiment may contain a polyphenylene ether compound containing two or more carbon-carbon unsaturated double bonds. The polyphenylene ether compound containing two or more carbon-carbon unsaturated double bonds is preferably a polyphenylene ether compound having two or more groups selected from the group consisting of a (meth)acrylic group, a maleimide group, and a vinylbenzyl group at its terminals. Use of such polyphenylene ether compounds tends to more effectively improve the dielectric properties and low water absorption of printed wiring boards and the like. These will be explained in detail below.

[0058] The polyphenylene ether compound containing two or more carbon-carbon unsaturated double bonds is exemplified by a compound having a phenylene ether skeleton represented by the following formula (X1).

[0059] [ka] (In formula (X1), R 24 , R 25 , R 26 , and ,R 27 may be the same or different and represent an alkyl group having 6 or less carbon atoms, an aryl group, a halogen atom, or a hydrogen atom.

[0060] The polyphenylene ether compound containing two or more carbon-carbon unsaturated double bonds has the formula (X2): [ka] (In formula (X2), R 28 , R 29 , R 30 , R 34 , and ,R 35 may be the same or different and represent an alkyl group having 6 or less carbon atoms or a phenyl group. 31 , R 32 , and ,R 33 may be the same or different and are a hydrogen atom, an alkyl group having 6 or less carbon atoms, or a phenyl group. and / or a repeating unit represented by formula (X3): [ka] (In formula (X3), R 36 , R 37 , R 38 , R 39 , R 40 , R 41 , R 42 , and ,R 43 may be the same or different and are a hydrogen atom, an alkyl group having 6 or less carbon atoms, or a phenyl group. -A- is a linear, branched, or cyclic divalent hydrocarbon group having 20 or less carbon atoms.

[0061] The polyphenylene ether compound containing two or more carbon-carbon unsaturated double bonds is preferably a modified polyphenylene ether compound in which some or all of the terminals are functionalized with ethylenically unsaturated groups (hereinafter, sometimes referred to as "modified polyphenylene ether compound (g)"). A modified polyphenylene ether compound having two or more terminal groups selected from the group consisting of (meth)acrylic groups, maleimide groups, and vinylbenzyl groups is more preferred. By using such a modified polyphenylene ether compound (g), the dielectric loss tangent (Df) of the cured product of the resin composition can be further reduced, and the cured product can have low water absorption and high metal foil peel strength. These compounds may be used alone or in combination of two or more.

[0062] The modified polyphenylene ether compound (g) includes a compound represented by formula (OP-1). [ka] (In formula (OP-1), X represents an aromatic group, -(YO)n2- represents a polyphenylene ether structure, and R 1 , R 2 , and ,R 3 each independently represents a hydrogen atom, an alkyl group, an alkenyl group, or an alkynyl group, n1 represents an integer of 1 to 6, n2 represents an integer of 1 to 100, and n3 represents an integer of 2 to 4. When n2 is an integer of 2 or more, and when n3 is an integer of 2 or more, the n2 structural units (YO) and / or the n3 structural units may be the same or different. n3 is preferably 2.

[0063] The modified polyphenylene ether compound (g) in this embodiment is preferably a compound represented by formula (OP-2). [ka] where -(OXO)- is a compound of formula (OP-3): [ka] (In formula (OP-3), R 4 , R 5 , R 6 , R 10 , and ,R 11 R may be the same or different and is an alkyl group or a phenyl group having 6 or less carbon atoms. 7 , R 8 , and ,R 9 may be the same or different and are a hydrogen atom, an alkyl group having 6 or less carbon atoms, or a phenyl group. and / or formula (OP-4): [ka] (In formula (OP-4), R 12 , R 13 , R 14 , R 15 , R 16 , R 17 , R 18 , and ,R 19 may be the same or different and are a hydrogen atom, an alkyl group having 6 or less carbon atoms, or a phenyl group. -A- is a linear, branched, or cyclic divalent hydrocarbon group having 20 or less carbon atoms.

[0064] Also, -(YO)- is a group represented by the formula (OP-5): [ka] (In formula (OP-5), R 20 , R 21 R may be the same or different and is an alkyl group or a phenyl group having 6 or less carbon atoms. 22 , R 23 may be the same or different and are a hydrogen atom, an alkyl group having 6 or less carbon atoms, or a phenyl group. In formula (OP-2), a and b, at least one of which is not 0, represent an integer of 0 to 100, preferably an integer of 0 to 50, and more preferably an integer of 1 to 30. When a and / or b are an integer of 2 or greater, two or more -(YO)- groups may each independently represent an arrangement of one type of structure, or two or more types of structures may be arranged in blocks or randomly.

[0065] Examples of -A- in formula (OP-4) include divalent organic groups such as a methylene group, an ethylidene group, a 1-methylethylidene group, a 1,1-propylidene group, a 1,4-phenylenebis(1-methylethylidene) group, a 1,3-phenylenebis(1-methylethylidene) group, a cyclohexylidene group, a phenylmethylene group, a naphthylmethylene group, and a 1-phenylethylidene group, but are not limited to these.

[0066] Among the modified polyphenylene ether compounds (g), R 4 , R 5 , R 6 , R 10 , R 11 , R 20 , and ,R 21 is an alkyl group having 3 or less carbon atoms, and R 7 , R 8 , R 9 , R 12 , R 13 , R 14 , R 15 , R 16 , R 17 , R 18 , R 19 , R 22 , and ,R 23is a hydrogen atom or an alkyl group having 3 or less carbon atoms, and it is particularly preferred that -(OXO)- represented by formula (OP-3) or formula (OP-4) is formula (OP-9), formula (OP-10), and / or formula (OP-11), and -(YO)- represented by formula (OP-5) is formula (OP-12) or formula (OP-13). When a and / or b are integers of 2 or more, the two or more -(YO)- may each independently be a structure in which two or more of formula (OP-12) and / or formula (OP-13) are arranged, or a structure in which formula (OP-12) and formula (OP-13) are arranged in blocks or randomly.

[0067] [ka] [ka] (In formula (OP-10), R 44 , R 45 , R 46 , and ,R 47 may be the same or different and are a hydrogen atom or a methyl group. -B- is a linear, branched, or cyclic divalent hydrocarbon group having 20 or less carbon atoms. Specific examples of -B- include the same as the specific examples of -A- in formula (OP-4). [ka] (In formula (OP-11), -B- is a linear, branched, or cyclic divalent hydrocarbon group having 20 or less carbon atoms.) Specific examples of -B- include the same as the specific examples of -A- in formula (OP-4). [ka] [ka]

[0068] For details of the polyphenylene ether compound containing two or more carbon-carbon unsaturated double bonds, please refer to the description in JP 2018-016709 A, the contents of which are incorporated herein by reference.

[0069] The polyphenylene ether compound containing two or more carbon-carbon unsaturated double bonds (preferably a modified polyphenylene ether compound (g)) preferably has a polystyrene-equivalent number average molecular weight of 500 or more and 3,000 or less, as determined by a GPC (gel permeation chromatography) method. When the number average molecular weight is 500 or more, stickiness tends to be further suppressed when the resin composition of the present embodiment is formed into a coating film. When the number average molecular weight is 3,000 or less, solubility in solvents tends to be further improved. Furthermore, the weight average molecular weight of the polyphenylene ether compound containing two or more carbon-carbon unsaturated double bonds (preferably the modified polyphenylene ether compound (g)) as measured by GPC in terms of polystyrene is preferably 800 or more and 10,000 or less, and more preferably 800 or more and 5,000 or less. By setting the weight average molecular weight at or above the lower limit, the relative permittivity (Dk) and dielectric loss tangent (Df) of the cured product of the resin composition tend to be lower, while by setting the weight average molecular weight at or below the upper limit, the solubility, low viscosity, and moldability of the resin composition in a solvent when preparing a varnish or the like, which will be described later, tend to be improved. Furthermore, in the case of the modified polyphenylene ether compound (g), the terminal carbon-carbon unsaturated double bond equivalent is preferably 400 to 5000 g per carbon-carbon unsaturated double bond, more preferably 400 to 2500 g. By setting the equivalent at or above the lower limit, the relative dielectric constant (Dk) and dielectric loss tangent (Df) of the cured product of the resin composition tend to be lower. By setting the equivalent at or below the upper limit, the solubility, low viscosity, and moldability of the resin composition in solvents tend to be further improved.

[0070] When the resin composition of this embodiment contains a polyphenylene ether compound containing two or more carbon-carbon unsaturated double bonds, the lower limit of the content of the polyphenylene ether compound containing two or more carbon-carbon unsaturated double bonds is preferably 1 part by mass or more, more preferably 3 parts by mass or more, even more preferably 5 parts by mass or more, even more preferably 7 parts by mass or more, and even more preferably 10 parts by mass or more, per 100 parts by mass of the resin solids in the resin composition. By setting the content at or above the lower limit, the low water absorption and low dielectric properties (Dk and / or Df) of the resulting cured product tend to be further improved. Furthermore, the upper limit of the content of the polyphenylene ether compound containing two or more carbon-carbon unsaturated double bonds is preferably 70 parts by mass or less, more preferably 60 parts by mass or less, even more preferably 50 parts by mass or less, even more preferably 40 parts by mass or less, even more preferably 35 parts by mass or less, even more preferably 25 parts by mass or less, and may even be 20 parts by mass or less, per 100 parts by mass of the resin solids in the resin composition. By ensuring that the content is equal to or less than the above upper limit, the heat resistance and chemical resistance of the resulting cured product tend to be further improved. The resin composition of the present embodiment may contain only one polyphenylene ether compound containing two or more carbon-carbon unsaturated double bonds, or may contain two or more polyphenylene ether compounds. When two or more polyphenylene ether compounds are contained, the total amount is preferably within the above range.

[0071] <<Cyanate ester compounds>> The resin composition of the present embodiment may contain a cyanate ester compound. The cyanate ester compound is not particularly limited as long as it contains one or more (preferably 2 to 12, more preferably 2 to 6, even more preferably 2 to 4, still more preferably 2 or 3, and still more preferably 2) cyanate groups (cyanato groups) in one molecule, and a wide range of compounds commonly used in the field of printed wiring boards can be used. In addition, the cyanate ester compound is preferably a compound in which the cyanate group is directly bonded to an aromatic skeleton (aromatic ring). Examples of the cyanate ester compound include at least one selected from the group consisting of phenol novolac-type cyanate ester compounds, naphthol aralkyl-type cyanate ester compounds (naphthol aralkyl-type cyanates), naphthylene ether-type cyanate ester compounds, biphenyl aralkyl-type cyanate ester compounds, xylene resin-type cyanate ester compounds, trisphenolmethane-type cyanate ester compounds, adamantane skeleton-type cyanate ester compounds, bisphenol M-type cyanate ester compounds, bisphenol A-type cyanate ester compounds, and diallyl bisphenol A-type cyanate ester compounds. Among these, from the viewpoint of further improving the low water absorption of the resulting cured product, at least one selected from the group consisting of phenol novolac-type cyanate ester compounds, naphthol aralkyl-type cyanate ester compounds, naphthylene ether-type cyanate ester compounds, xylene resin-type cyanate ester compounds, bisphenol M-type cyanate ester compounds, bisphenol A-type cyanate ester compounds, and diallyl bisphenol A-type cyanate ester compounds is preferred, at least one selected from the group consisting of phenol novolac-type cyanate ester compounds and naphthol aralkyl-type cyanate ester compounds is more preferred, and naphthol aralkyl-type cyanate ester compounds are even more preferred. These cyanate ester compounds may be prepared by known methods, or commercially available products may be used. Note that cyanate ester compounds having a naphthol aralkyl skeleton, naphthylene ether skeleton, xylene skeleton, trisphenolmethane skeleton, or adamantane skeleton have a relatively large functional group equivalent weight and fewer unreacted cyanate ester groups, so cured products of resin compositions using these compounds tend to have even better low water absorption. Furthermore, due mainly to the presence of an aromatic skeleton or an adamantane skeleton, plating adhesion tends to be further improved.

[0072] As the naphthol aralkyl cyanate ester compound, a compound represented by formula (1) is more preferred.

[0073] [ka] (In formula (1), R 3 each independently represents a hydrogen atom or a methyl group, and n3 represents an integer of 1 or greater.

[0074] In formula (1), R 3 each independently represents a hydrogen atom or a methyl group, and among these, a hydrogen atom is preferred. In formula (1), n3 is an integer of 1 or more, preferably an integer of 1 to 20, more preferably an integer of 1 to 10, and even more preferably an integer of 1 to 6.

[0075] The novolac-type cyanate ester compound is not particularly limited, but is preferably, for example, a compound represented by the following formula (VII). [ka] (In formula (VII), R 6 each independently represents a hydrogen atom or a methyl group, and n7 represents an integer of 1 or greater.

[0076] In formula (VII), R 6 each independently represents a hydrogen atom or a methyl group, and among these, a hydrogen atom is preferred. In formula (VII), n7 is an integer of 1 or more, preferably an integer of 1 to 20, more preferably an integer of 1 to 10, and even more preferably an integer of 1 to 6.

[0077] As the bisphenol A type cyanate ester compound, one or more compounds selected from the group consisting of 2,2-bis(4-cyanatophenyl)propane and prepolymers of 2,2-bis(4-cyanatophenyl)propane may be used.

[0078] The resin composition of this embodiment preferably contains a cyanate ester compound in an amount that does not impair the effects of the present invention. When the resin composition of this embodiment contains a cyanate ester compound, the lower limit of the cyanate ester compound content is preferably 0.1 parts by mass or more, more preferably 2 parts by mass or more, and even more preferably 4 parts by mass or more, per 100 parts by mass of the resin solid content in the resin composition. When the cyanate ester compound content is 0.1 parts by mass or more, the heat resistance, flame resistance, chemical resistance, low dielectric constant, low dielectric loss tangent, and insulating properties of the resulting cured product tend to be improved. When the resin composition of this embodiment contains a cyanate ester compound, the upper limit of the cyanate ester compound content is preferably 70 parts by mass or less, more preferably 50 parts by mass or less, even more preferably 40 parts by mass or less, even more preferably 30 parts by mass or less, even more preferably 20 parts by mass or less, and may be 10 parts by mass or less, or even 5 parts by mass or less, per 100 parts by mass of the resin solid content in the resin composition. The resin composition of the present embodiment may contain only one type of cyanate ester compound, or may contain two or more types. When two or more types are contained, the total amount is preferably in the above range.

[0079] <<Epoxy compounds>> The resin composition of the present embodiment may contain an epoxy compound. The epoxy compound is not particularly limited as long as it is a compound or resin having one or more (preferably 2 to 12, more preferably 2 to 6, even more preferably 2 to 4, even more preferably 2 or 3, and even more preferably 2) epoxy groups in one molecule, and a wide range of compounds commonly used in the field of printed wiring boards can be used. Examples of epoxy compounds include bisphenol A epoxy resins, bisphenol E epoxy resins, bisphenol F epoxy resins, bisphenol S epoxy resins, phenol novolac epoxy resins, bisphenol A novolac epoxy resins, glycidyl ester epoxy resins, aralkyl novolac epoxy resins, biphenyl aralkyl epoxy resins, naphthylene ether epoxy resins, cresol novolac epoxy resins, multifunctional phenol epoxy resins, naphthalene epoxy resins, anthracene epoxy resins, naphthalene skeleton-modified novolac epoxy resins, phenol aralkyl epoxy resins, naphthol aralkyl epoxy resins, dicyclopentadiene epoxy resins, biphenyl epoxy resins, alicyclic epoxy resins, polyol epoxy resins, phosphorus-containing epoxy resins, glycidyl amines, glycidyl esters, compounds in which the double bond of butadiene or the like has been epoxidized, and compounds obtained by reacting hydroxyl group-containing silicone resins with epichlorohydrin. The use of these compounds improves the moldability and adhesion of the resin composition. Among these, from the viewpoint of further improving flame retardancy and heat resistance, biphenyl aralkyl type epoxy resins, naphthylene ether type epoxy resins, polyfunctional phenol type epoxy resins, and naphthalene type epoxy resins are preferred, and biphenyl aralkyl type epoxy resins are more preferred.

[0080] The resin composition of this embodiment preferably contains an epoxy compound within a range that does not impair the effects of the present invention. When the resin composition of this embodiment contains an epoxy compound, the content thereof is preferably 0.1 parts by mass or more, more preferably 1 part by mass or more, and even more preferably 2 parts by mass or more, per 100 parts by mass of the resin solid content in the resin composition. When the epoxy compound content is 0.1 parts by mass or more, the metal foil peel strength and toughness tend to be improved. When the resin composition of this embodiment contains an epoxy compound, the upper limit of the epoxy compound content is preferably 50 parts by mass or less, more preferably 30 parts by mass or less, even more preferably 20 parts by mass or less, even more preferably 10 parts by mass or less, even more preferably 8 parts by mass or less, and even more preferably 5 parts by mass or less, per 100 parts by mass of the resin solid content in the resin composition. When the epoxy compound content is 50 parts by mass or less, the electrical properties of the resulting cured product tend to be improved. The resin composition in the present embodiment may contain only one type of epoxy compound, or may contain two or more types. When two or more types are contained, the total amount is preferably in the above range. The resin composition of the present embodiment may also be configured to be substantially free of epoxy compounds, which means that the content of the epoxy compounds is less than 0.1 parts by mass, preferably less than 0.01 parts by mass, and even less than 0.001 parts by mass, per 100 parts by mass of the resin solid content in the resin composition.

[0081] <<Phenol compounds>> The resin composition of the present embodiment may contain a phenol compound. The phenol compound is not particularly limited as long as it has one or more (preferably 2 to 12, more preferably 2 to 6, even more preferably 2 to 4, even more preferably 2 or 3, and even more preferably 2) phenolic hydroxyl groups in one molecule, and a wide range of compounds commonly used in the field of printed wiring boards can be used. Examples of the phenol compound include bisphenol A type phenolic resins, bisphenol E type phenolic resins, bisphenol F type phenolic resins, bisphenol S type phenolic resins, phenol novolac resins, bisphenol A novolac type phenolic resins, glycidyl ester type phenolic resins, aralkyl novolac phenolic resins, biphenyl aralkyl type phenolic resins, cresol novolac type phenolic resins, polyfunctional phenolic resins, naphthol resins, naphthol novolac resins, polyfunctional naphthol resins, anthracene type phenolic resins, naphthalene skeleton-modified novolac type phenolic resins, phenol aralkyl type phenolic resins, naphthol aralkyl type phenolic resins, dicyclopentadiene type phenolic resins, biphenyl type phenolic resins, alicyclic phenolic resins, polyol type phenolic resins, phosphorus-containing phenolic resins, and hydroxyl group-containing silicone resins. Among these, from the viewpoint of further improving the flame resistance of the resulting cured product, it is preferable to use at least one selected from the group consisting of biphenyl aralkyl phenolic resins, naphthol aralkyl phenolic resins, phosphorus-containing phenolic resins, and hydroxyl group-containing silicone resins.

[0082] The resin composition of the present embodiment preferably contains a phenolic compound within a range that does not impair the effects of the present invention. When the resin composition of the present embodiment contains a phenolic compound, the content thereof is preferably 0.1 parts by mass or more and 50 parts by mass or less per 100 parts by mass of the resin solid content in the resin composition. The resin composition of the present embodiment may contain only one type of phenol compound, or may contain two or more types. When two or more types are contained, the total amount is preferably in the above range. The resin composition of the present embodiment may be configured to be substantially free of phenolic compounds, meaning that the content of phenolic compounds is less than 0.1 parts by mass per 100 parts by mass of the resin solid content in the resin composition.

[0083] <<Alkenyl-substituted nadimide compounds>> The alkenyl-substituted nadiimide compound is not particularly limited as long as it is a compound having one or more alkenyl-substituted nadiimide groups in the molecule. Among these, the compound represented by formula (AN-1) is preferred. By using such an alkenyl-substituted nadiimide compound, the thermal expansion coefficient of the obtained cured product tends to be further reduced and the heat resistance tends to be further improved. [ka] (In formula (AN-1), each R1 independently represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms, and each R2 independently represents an alkylene group having 1 to 6 carbon atoms, a phenylene group, a biphenylene group, a naphthylene group, a group represented by formula (AN-2), or a group represented by formula (AN-3).) [ka] (In formula (AN-2), R3 represents a methylene group, an isopropylidene group, -C(=O)-, -O-, -S-, or -S(=O)2-.) [ka] (In formula (AN-3), each R4 independently represents an alkylene group having 1 to 4 carbon atoms or a cycloalkylene group having 5 to 8 carbon atoms.)

[0084] Among the compounds represented by formula (AN-1), compounds represented by formula (AN-4) and (AN-5) are preferred. By using such alkenyl-substituted nadimide compounds, the thermal expansion coefficient of the obtained cured product tends to be further reduced, and the heat resistance tends to be further improved. [ka] [ka]

[0085] Alternatively, commercially available alkenyl-substituted nadimide compounds can be used. Examples of commercially available alkenyl-substituted nadimide compounds include, but are not limited to, BANI-M (manufactured by Maruzen Petrochemical Co., Ltd., a compound represented by formula (AN-4)) and BANI-X (manufactured by Maruzen Petrochemical Co., Ltd., a compound represented by formula (AN-5)).

[0086] The resin composition of the present embodiment preferably contains an alkenyl-substituted nadimide compound within a range that does not impair the effects of the present invention. When the resin composition of the present embodiment contains an alkenyl-substituted nadimide compound, the content thereof is preferably 0.1 parts by mass or more and 50 parts by mass or less per 100 parts by mass of the resin solid content in the resin composition. The resin composition of the present embodiment may contain only one alkenyl-substituted nadimide compound, or may contain two or more alkenyl-substituted nadimide compounds. When two or more alkenyl-substituted nadimide compounds are contained, the total amount is preferably in the above range. The resin composition of the present embodiment may be configured to be substantially free of alkenyl-substituted nadimide compounds, meaning that the content of the alkenyl-substituted nadimide compounds is less than 0.1 parts by mass per 100 parts by mass of the resin solid content in the resin composition.

[0087] <<Oxetane resin>> The resin composition of the present embodiment may contain an oxetane resin. The oxetane resin is not particularly limited as long as it is a compound having one or more oxetanyl groups (preferably 2 to 12, more preferably 2 to 6, even more preferably 2 to 4, even more preferably 2 or 3, and still more preferably 2), and a wide range of compounds commonly used in the field of printed wiring boards can be used. Examples of oxetane resins include oxetane, alkyloxetane (e.g., 2-methyloxetane, 2,2-dimethyloxetane, 3-methyloxetane, 3,3-dimethyloxetane, etc.), 3-methyl-3-methoxymethyloxetane, 3,3-di(trifluoromethyl)oxetane, 2-chloromethyloxetane, 3,3-bis(chloromethyl)oxetane, biphenyl-type oxetane, OXT-101 (manufactured by Toagosei Co., Ltd.), and OXT-121 (manufactured by Toagosei Co., Ltd.).

[0088] The resin composition of this embodiment preferably contains an oxetane resin to a degree that does not impair the effects of the present invention. When the resin composition of this embodiment contains an oxetane resin, the content thereof is preferably 0.1 parts by mass or more, more preferably 1 part by mass or more, and even more preferably 2 parts by mass or more, per 100 parts by mass of the resin solid content in the resin composition. When the oxetane resin content is 0.1 parts by mass or more, the metal foil peel strength and toughness tend to be improved. When the resin composition of this embodiment contains an oxetane resin, the upper limit of the oxetane resin content is preferably 50 parts by mass or less, more preferably 30 parts by mass or less, even more preferably 20 parts by mass or less, even more preferably 10 parts by mass or less, and even more preferably 8 parts by mass or less, per 100 parts by mass of the resin solid content in the resin composition. When the oxetane resin content is 50 parts by mass or less, the electrical properties of the resulting cured product tend to be improved. The resin composition of the present embodiment may contain only one type of oxetane resin, or may contain two or more types. When two or more types are contained, the total amount is preferably in the above range. The resin composition of the present embodiment may be configured to be substantially free of oxetane resin, meaning that the content of oxetane resin is less than 0.1 parts by mass per 100 parts by mass of the resin solid content in the resin composition.

[0089] <<Benzoxazine compounds>> The resin composition of the present embodiment may contain a benzoxazine compound. The benzoxazine compound is not particularly limited as long as it has two or more (preferably 2 to 12, more preferably 2 to 6, even more preferably 2 to 4, still more preferably 2 or 3, and even more preferably 2) dihydrobenzoxazine rings in one molecule, and a wide range of compounds commonly used in the field of printed wiring boards can be used. Examples of benzoxazine compounds include bisphenol A-type benzoxazine BA-BXZ (manufactured by Konishi Chemical Co., Ltd.), bisphenol F-type benzoxazine BF-BXZ (manufactured by Konishi Chemical Co., Ltd.), and bisphenol S-type benzoxazine BS-BXZ (manufactured by Konishi Chemical Co., Ltd.).

[0090] The resin composition of the present embodiment preferably contains a benzoxazine compound within a range that does not impair the effects of the present invention. When the resin composition of the present embodiment contains a benzoxazine compound, the content thereof is preferably 0.1 parts by mass or more and 50 parts by mass or less per 100 parts by mass of the resin solid content in the resin composition. The resin composition of the present embodiment may contain only one type of benzoxazine compound, or may contain two or more types. When two or more types are contained, the total amount is preferably in the above range. The resin composition of the present embodiment may also be configured to be substantially free of benzoxazine compounds, meaning that the content of the benzoxazine compounds is less than 0.1 parts by mass per 100 parts by mass of the resin solid content in the resin composition.

[0091] The content (total amount) of the thermosetting compound (C) in the resin composition of this embodiment is preferably 5 parts by mass or more, more preferably 10 parts by mass or more, even more preferably 20 parts by mass or more, even more preferably 30 parts by mass or more, and even more preferably 35 parts by mass or more, per 100 parts by mass of resin solids. By ensuring that the content is above the lower limit, heat resistance, plating adhesion, low thermal expansion, and the like tend to be further improved. Furthermore, the upper limit of the content of the thermosetting compound (C) is preferably 95 parts by mass or less, more preferably 85 parts by mass or less, even more preferably 75 parts by mass or less, even more preferably 65 parts by mass or less, and even more preferably 50 parts by mass or less, per 100 parts by mass of resin solids. By ensuring that the content is below the upper limit, low dielectric properties and low water absorption tend to be further improved. The resin composition of the present embodiment may contain only one type of thermosetting compound (C), or may contain two or more types. When two or more types are contained, the total amount is preferably in the above range.

[0092] <Elastomer> The resin composition of the present embodiment may contain an elastomer. In the present embodiment, the elastomer is not particularly limited, and examples thereof include at least one selected from the group consisting of polyisoprene, polybutadiene, styrene butadiene, butyl rubber, ethylene propylene rubber, styrene butadiene ethylene, styrene butadiene styrene, styrene isoprene styrene, styrene ethylene butylene styrene, styrene propylene styrene, styrene ethylene propylene styrene, fluororubber, silicone rubber, hydrogenated compounds thereof, alkyl compounds thereof, and copolymers thereof. The elastomer may be either a thermoplastic elastomer or a thermosetting elastomer, but is preferably a thermoplastic elastomer.

[0093] The number average molecular weight of the elastomer used in this embodiment is preferably 50,000 or more. By setting the number average molecular weight to 50,000 or more, the low dielectric properties of the resulting cured product tend to be more excellent. The number average molecular weight is preferably 60,000 or more, more preferably 70,000 or more, and even more preferably 80,000 or more. The upper limit of the number average molecular weight of the thermal elastomer is preferably 400,000 or less, more preferably 350,000 or less, and even more preferably 300,000 or less. By setting the number average molecular weight below the upper limit, the solubility of the elastomer component in the resin composition tends to be improved. When the resin composition of the present embodiment contains two or more elastomers, it is preferable that the number average molecular weight of the mixture thereof falls within the above range.

[0094] In this embodiment, the elastomer is preferably a thermoplastic elastomer containing styrene monomer units and conjugated diene monomer units (hereinafter referred to as "thermoplastic elastomer (E)"). By using such a thermoplastic elastomer (E), the obtained cured product has excellent low dielectric properties.

[0095] The thermoplastic elastomer (E) contains a styrene monomer unit. The inclusion of the styrene monomer unit improves the solubility of the thermoplastic elastomer (E) in the resin composition. Examples of styrene monomers include styrene, α-methylstyrene, p-methylstyrene, divinylbenzene (vinylstyrene), N,N-dimethyl-p-aminoethylstyrene, and N,N-diethyl-p-aminoethylstyrene. Among these, from the viewpoints of availability and productivity, one or more selected from the group consisting of styrene, α-methylstyrene, and p-methylstyrene are preferred. Among these, styrene is particularly preferred. The content of styrene monomer units in the thermoplastic elastomer (E) is preferably in the range of 10 to 50% by mass of all monomer units, more preferably in the range of 13 to 45% by mass, and even more preferably in the range of 15 to 40% by mass. If the content of styrene monomer units is 50% by mass or less, the adhesion and tackiness to the substrate and the like will be better. On the other hand, if the content is 10% by mass or more, the adhesion can be suppressed, adhesive residue and stop marks are less likely to occur, and the adhesive surfaces tend to be easily peeled from each other, which is preferable. The thermoplastic elastomer (E) may contain only one type of styrene monomer unit, or may contain two or more types. When two or more types are contained, the total amount is preferably within the above range. The method for measuring the content of styrene monomer units in the thermoplastic elastomer (E) can be found in International Publication No. 2017 / 126469, the contents of which are incorporated herein by reference. The same applies to the conjugated diene monomer units, etc., described below.

[0096] The thermoplastic elastomer (E) contains a conjugated diene monomer unit. The inclusion of the conjugated diene monomer unit improves the solubility of the thermoplastic elastomer (E) in the resin composition. The conjugated diene monomer is not particularly limited as long as it is a diolefin having one pair of conjugated double bonds. Examples of the conjugated diene monomer include 1,3-butadiene, 2-methyl-1,3-butadiene (isoprene), 2,3-dimethyl-1,3-butadiene, 1,3-pentadiene, 2-methyl-1,3-pentadiene, 1,3-hexadiene, and farnesene. 1,3-butadiene and / or isoprene are preferred, and 1,3-butadiene is more preferred. The thermoplastic elastomer (E) may contain only one type of conjugated diene monomer unit, or may contain two or more types.

[0097] In the thermoplastic elastomer (E), the mass ratio of the styrene monomer units to the conjugated diene monomer units is preferably in the range of 5 / 95 to 80 / 20, more preferably 7 / 93 to 77 / 23, and even more preferably 10 / 90 to 70 / 30. When the mass ratio of the styrene monomer units to the conjugated diene monomer units is in the range of 5 / 95 to 80 / 20, the adhesion can be suppressed from increasing, the adhesion strength can be maintained high, and the adhesive surfaces can be easily peeled from each other.

[0098] The thermoplastic elastomer (E) may have all of its conjugated diene bonds hydrogenated, some of its conjugated diene bonds hydrogenated, or no conjugated diene bonds hydrogenated.

[0099] The thermoplastic elastomer (E) may or may not contain other monomer units in addition to the styrene monomer units and the conjugated diene monomer units. Examples of other monomer units include aromatic vinyl compound units other than the styrene monomer units. In the thermoplastic elastomer (E), the sum of styrene monomer units and conjugated diene monomer units preferably accounts for 90 mass% or more of all monomer units, more preferably 95 mass% or more, even more preferably 97 mass% or more, and even more preferably 99 mass% or more. The thermoplastic elastomer (E) may contain only one type of styrene monomer unit and one type of conjugated diene monomer unit, or may contain two or more types. When two or more types are contained, the total amount is preferably within the above range.

[0100] The thermoplastic elastomer (E) may be a block polymer or a random polymer, and may be a hydrogenated elastomer in which the conjugated diene monomer units are hydrogenated, an unhydrogenated elastomer in which the conjugated diene monomer units are not hydrogenated, or a partially hydrogenated elastomer in which the conjugated diene monomer units are partially hydrogenated. In one embodiment of this embodiment, the thermoplastic elastomer (E) is a hydrogenated elastomer. Here, the hydrogenated elastomer means, for example, a thermoplastic elastomer in which double bonds based on conjugated diene monomer units in the thermoplastic elastomer have been hydrogenated, and includes elastomers with a hydrogenation rate (hydrogenation rate) of 100% or more as well as elastomers with a hydrogenation rate of 80% or more. The hydrogenation rate in the hydrogenated elastomer is preferably 85% or more, more preferably 90% or more, and even more preferably 95% or more. In this embodiment, the hydrogenation rate is 1 It is calculated from the results of H-NMR spectroscopy. In one embodiment of this embodiment, the thermoplastic elastomer (E) is an unhydrogenated elastomer. Here, the unhydrogenated elastomer includes an elastomer having a hydrogenation rate (hydrogenation rate), i.e., a rate of hydrogenated double bonds based on conjugated diene monomer units in the elastomer, of 20% or less. The hydrogenation rate in the unhydrogenated elastomer is preferably 15% or less, more preferably 10% or less, and even more preferably 5% or less. On the other hand, a partially hydrogenated elastomer means a thermoplastic elastomer in which some of the double bonds based on the conjugated diene monomer units are hydrogenated, and usually refers to a hydrogenation rate (hydrogenation rate) of less than 80% but more than 20%.

[0101] Examples of commercially available thermoplastic elastomers (E) used in this embodiment include SEPTON (registered trademark) 2104 manufactured by Kuraray Co., Ltd., SOE (registered trademark) S1606, S1613, S1609, and S1605 manufactured by Asahi Kasei Corporation, and DYNARON (registered trademark) 9901P and TR2250 manufactured by JSR Corporation.

[0102] When the resin composition of this embodiment contains an elastomer (preferably a thermoplastic elastomer (E)), the content thereof is preferably 1 part by mass or more, more preferably 3 parts by mass or more, even more preferably 7 parts by mass or more, even more preferably 10 parts by mass or more, and even more preferably 12 parts by mass or more, per 100 parts by mass of the resin solid content. By setting the content at or above the lower limit, low dielectric properties tend to be further improved. Furthermore, the upper limit of the content of the elastomer is preferably 35 parts by mass or less, more preferably 30 parts by mass or less, even more preferably 25 parts by mass or less, even more preferably 21 parts by mass or less, and even more preferably 18 parts by mass or less, per 100 parts by mass of the resin solid content. By setting the content at or below the upper limit, heat resistance tends to be further improved. The resin composition of the present embodiment may contain only one type of elastomer, or may contain two or more types. When two or more types are contained, the total amount is preferably in the above range.

[0103] <Active ester compounds> The resin composition of the present embodiment may contain an active ester compound. The active ester compound is not particularly limited, and examples thereof include compounds having two or more (preferably 2 to 12, more preferably 2 to 6, even more preferably 2 to 4, still more preferably 2 or 3, and even more preferably 2) active ester groups in one molecule. The active ester compound may be a straight-chain, branched, or cyclic compound. Among these, from the viewpoint of further improving the heat resistance of the resulting cured product, an active ester compound obtained by reacting a carboxylic acid compound and / or a thiocarboxylic acid compound with a hydroxy compound and / or a thiol compound is preferred, an active ester compound obtained by reacting a carboxylic acid compound with one or more compounds selected from the group consisting of a phenol compound, a naphthol compound, and a thiol compound is more preferred, an aromatic compound obtained by reacting a carboxylic acid compound with an aromatic compound having a phenolic hydroxyl group and having two or more active ester groups per molecule is even more preferred, and an aromatic compound obtained by reacting a compound having two or more carboxylic acids per molecule with an aromatic compound having a phenolic hydroxyl group and having two or more active ester groups per molecule is particularly preferred. The carboxylic acid compound may be one or more selected from the group consisting of benzoic acid, acetic acid, succinic acid, maleic acid, itaconic acid, phthalic acid, isophthalic acid, terephthalic acid, and pyromellitic acid. Among these, from the viewpoint of further improving the heat resistance of the resulting cured product, one or more selected from the group consisting of succinic acid, maleic acid, itaconic acid, phthalic acid, isophthalic acid, and terephthalic acid are preferred, and one or more selected from the group consisting of isophthalic acid and terephthalic acid are more preferred. The thiocarboxylic acid compound may be one or more selected from thioacetic acid and thiobenzoic acid. The phenol compound or naphthol compound may be at least one selected from the group consisting of hydroquinone, resorcinol, bisphenol A, bisphenol F, bisphenol S, phenolphthalene, methylated bisphenol A, methylated bisphenol F, methylated bisphenol S, phenol, o-cresol, m-cresol, p-cresol, catechol, α-naphthol, β-naphthol, 1,5-dihydroxynaphthalene, 1,6-dihydroxynaphthalene, 2,6-dihydroxynaphthalene, dihydroxybenzophenone, trihydroxybenzophenone, tetrahydroxybenzophenone, phloroglucinol, benzenetriol, dicyclopentadienyldiphenol, and phenol novolak. From the viewpoint of further improving the heat resistance and solvent solubility of the resulting cured product, bisphenol A, bisphenol F, bisphenol S, methylated bisphenol S, phenol, o-cresol, m-cresol, p-cresol, catechol, α-naphthol, β-naphthol, 1,5-dihydroxynaphthalene, 1,6-dihydroxynaphthalene, 2,6-dihydroxynaphthalene, dihydroxybenzophenone, trihydroxybenzophenone, tetrahydroxybenzophenone, phloroglucinol, benzenetriol, dicyclopentadienyldiphenol, and phenol novolak. Preferred are bisphenol A, methylated bisphenol F, methylated bisphenol S, catechol, α-naphthol, β-naphthol, 1,5-dihydroxynaphthalene, 1,6-dihydroxynaphthalene, 2,6-dihydroxynaphthalene, dihydroxybenzophenone, trihydroxybenzophenone, tetrahydroxybenzophenone, phloroglucinone, benzenetriol, dicyclopentadienyl diphenol, and phenol novolak, and more preferred are one or more selected from the group consisting of catechol, 1,5-dihydroxynaphthalene, 1,6-dihydroxynaphthalene, 2,6-dihydroxynaphthalene, dihydroxybenzophenone, trihydroxybenzophenone, tetrahydroxybenzophenone, phloroglucinone, benzenetriol, dicyclopentadienyl diphenol, and phenol novolak.More preferred is one or more selected from the group consisting of 6-dihydroxynaphthalene, dihydroxybenzophenone, trihydroxybenzophenone, tetrahydroxybenzophenone, dicyclopentadienyl diphenol, and phenol novolac, and particularly preferred is one or more selected from the group consisting of dihydroxybenzophenone, trihydroxybenzophenone, tetrahydroxybenzophenone, dicyclopentadienyl diphenol, and phenol novolac (preferably one or more selected from the group consisting of dicyclopentadienyl diphenol and phenol novolac, more preferably dicyclopentadienyl diphenol). The thiol compound may be one or more selected from the group consisting of benzenedithiol and triazinedithiol. In addition, the active ester compound is preferably a compound having two or more carboxylic acids in one molecule and containing an aliphatic chain from the viewpoint of further improving compatibility with the epoxy compound, and is preferably a compound having an aromatic ring from the viewpoint of further improving heat resistance. More specific examples of the active ester compound include the active ester compounds described in JP-A-2004-277460.

[0104] The active ester compound may be a commercially available product or may be prepared by a known method. Examples of commercially available products include compounds containing a dicyclopentadienyldiphenol structure (e.g., EXB9451, EXB9460, EXB9460S, HPC-8000-65T (all manufactured by DIC Corporation)), acetylated phenol novolac (e.g., DC808 (manufactured by Mitsubishi Chemical Corporation)), and benzoylated phenol novolac (e.g., YLH1026, YLH1030, YLH1048 (all manufactured by Mitsubishi Chemical Corporation)). EXB9460S is preferred from the viewpoints of further improving the storage stability of the varnish and the low thermal expansion of the cured resin composition.

[0105] The active ester compound can be prepared by a known method, for example, by a condensation reaction between a carboxylic acid compound and a hydroxy compound. A specific example is a method of reacting (a) a carboxylic acid compound or its halide, (b) a hydroxy compound, and (c) an aromatic monohydroxy compound in a ratio of 0.05 to 0.75 moles of the phenolic hydroxyl group of (b) and 0.25 to 0.95 moles of (c) to 1 mole of the carboxyl group or acid halide group of (a).

[0106] The active ester compound is preferably contained within a range that does not impair the effects of the present invention. When the resin composition of the present embodiment contains an active ester compound, the amount of the active ester compound is preferably 1 part by mass or more and 90 parts by mass or less per 100 parts by mass of the resin solid content in the resin composition. The resin composition of the present embodiment may contain only one type of active ester compound, or may contain two or more types. When two or more types are contained, the total amount is preferably in the above range. The resin composition of the present embodiment may also be configured to be substantially free of active ester compounds, which means that the content of the active ester compounds is less than 1 part by mass, preferably less than 0.1 parts by mass, and more preferably less than 0.01 parts by mass, per 100 parts by mass of the resin solid content in the resin composition.

[0107] <Flame retardant> The resin composition of this embodiment may contain a flame retardant. Examples of the flame retardant include phosphorus-based flame retardants, halogen-based flame retardants, inorganic flame retardants, and silicone-based flame retardants, and phosphorus-based flame retardants are preferred. As the flame retardant, known ones can be used, for example, halogen-based flame retardants such as brominated epoxy resin, brominated polycarbonate, brominated polystyrene, brominated styrene, brominated phthalimide, tetrabromobisphenol A, pentabromobenzyl (meth)acrylate, pentabromotoluene, tribromophenol, hexabromobenzene, decabromodiphenyl ether, bis-1,2-pentabromophenylethane, chlorinated polystyrene, and chlorinated paraffin, red phosphorus, tricresyl phosphate, triphenyl phosphate, and cresyl diphenyl phosphate. Examples of flame retardants include phosphorus-based flame retardants such as phosphate, trixylenyl phosphate, trialkyl phosphate, dialkyl phosphate, tris(chloroethyl)phosphate, phosphazene, 1,3-phenylenebis(2,6-dixylenyl phosphate), and 10-(2,5-dihydroxyphenyl)-10H-9-oxa-10-phosphaphenanthrene-10-oxide; inorganic flame retardants such as aluminum hydroxide, magnesium hydroxide, partial boehmite, boehmite, zinc borate, and antimony trioxide; and silicone-based flame retardants such as silicone rubber and silicone resin. In this embodiment, among these, 1,3-phenylenebis(2,6-dixylenyl phosphate) is preferred because it does not impair the low dielectric properties.

[0108] When the resin composition of this embodiment contains a flame retardant, the content thereof is preferably 1 part by mass or more, more preferably 5 parts by mass or more, per 100 parts by mass of the resin solid content in the resin composition. The lower limit of the content of the flame retardant is preferably 25 parts by mass or less, more preferably 20 parts by mass or less. The flame retardants can be used alone or in combination of two or more. When two or more types are used, the total amount falls within the above range.

[0109] <Other fillers> In the resin composition of this embodiment, an inorganic filler that has not been treated with a surface treatment agent such as vinylsilane may or may not be used in combination. When used in combination, the inorganic filler (b2) may be used. Furthermore, in the resin composition of this embodiment, an organic filler may or may not be used in combination. Examples of organic fillers include styrene-type, butadiene-type, and acrylic-type rubber powders, core-shell-type rubber powders, silicone resin powders, silicone rubber powders, and silicone composite powders. When an organic filler is used in combination, its content is preferably 1 to 30 parts by mass per 100 parts by mass of the resin solid content in the resin composition.

[0110] <Dispersant> The resin composition of this embodiment may contain a dispersant. Dispersants commonly used in paints can be suitably used, and the type is not particularly limited. The dispersant is preferably a copolymer-based wetting dispersant, and specific examples thereof include DISPERBYK (registered trademark)-110, 111, 161, 180, 2009, 2152, 2155, BYK (registered trademark)-W996, W9010, W903, and W940, all manufactured by BYK Japan K.K.

[0111] When the resin composition of this embodiment contains a dispersant, the lower limit of the content thereof is preferably 0.01 parts by mass or more, more preferably 0.1 parts by mass or more, and may be 0.3 parts by mass or more, relative to 100 parts by mass of the resin solid content in the resin composition. The upper limit of the content of the dispersant is preferably 10 parts by mass or less, more preferably 5 parts by mass or less, and even more preferably 3 parts by mass or less, relative to 100 parts by mass of the resin solid content in the resin composition. The dispersant may be used alone or in combination of two or more. When two or more types are used, the total amount falls within the above range.

[0112] <Curing accelerator> The resin composition of the present embodiment may further contain a curing accelerator. The curing accelerator is not particularly limited, but examples thereof include imidazoles such as 2-ethyl-4-methylimidazole and triphenylimidazole; organic peroxides such as benzoyl peroxide, lauroyl peroxide, acetyl peroxide, parachlorobenzoyl peroxide, and di-tert-butyl-diperphthalate; azo compounds such as azobisisobutyronitrile; N,N-dimethylbenzylamine, N,N-dimethylaniline, N,N-dimethyltoluidine, 2-N-ethylanilinoethanol, tri-n-butylamine, pyridine, quinoline, N-methylmorpholine, triethanolamine, triethylenediamine, and tetramethylisothiazolinone. Examples of suitable organic metal salts include tertiary amines such as methylbutanediamine and N-methylpiperidine; phenols such as phenol, xylenol, cresol, resorcinol and catechol; organic metal salts such as lead naphthenate, lead stearate, zinc naphthenate, zinc octoate, manganese octoate, tin oleate, dibutyltin maleate, manganese naphthenate, cobalt naphthenate and iron acetylacetonate; compounds obtained by dissolving these organic metal salts in hydroxyl group-containing compounds such as phenol and bisphenol; inorganic metal salts such as tin chloride, zinc chloride and aluminum chloride; and organic tin compounds such as dioctyltin oxide, other alkyltins and alkyltin oxides. Preferred curing accelerators are imidazoles and organic metal salts, and it is more preferred to use both imidazoles and organic metal salts in combination. The resin composition of this embodiment may be configured to be substantially free of organic peroxides (for example, organic peroxides having a molecular weight of 30 to 500). "Substantially free" means that the amount is less than 0.1 parts by mass, and preferably 0.01 parts by mass or less, per 100 parts by mass of the resin solid content contained in the resin composition of this embodiment. By setting the amount within this range, a cured product with even better performance can be obtained. The resin composition of this embodiment may be configured to be substantially free of azo compounds (for example, azo compounds having a molecular weight of 30 to 500). "Substantially free" means that the amount is less than 0.1 parts by mass, and preferably 0.01 parts by mass or less, per 100 parts by mass of the resin solid content contained in the resin composition of this embodiment. By adjusting the amount to fall within this range, a cured product with even more excellent performance can be obtained.

[0113] When the resin composition of this embodiment contains a curing accelerator, the lower limit of the content is preferably 0.005 parts by mass or more, more preferably 0.01 parts by mass or more, and even more preferably 0.1 parts by mass or more, per 100 parts by mass of the resin solid content in the resin composition. The upper limit of the content of the curing accelerator is preferably 10 parts by mass or less, more preferably 5 parts by mass or less, and even more preferably 2 parts by mass or less, per 100 parts by mass of the resin solid content in the resin composition. The curing accelerators can be used alone or in combination of two or more. When two or more types are used, the total amount falls within the above range.

[0114] <Solvent> The resin composition of this embodiment may contain a solvent, preferably an organic solvent. When a solvent is contained, the resin composition of this embodiment is in a form (solution or varnish) in which at least a portion, preferably all, of the various resin solid components described above are dissolved or compatible in the solvent. The solvent is not particularly limited as long as it is a polar or non-polar organic solvent that can dissolve or compatible in at least a portion, preferably all, of the various resin solid components described above. Examples of polar organic solvents include ketones (e.g., acetone, methyl ethyl ketone, methyl isobutyl ketone, etc.), cellosolves (e.g., propylene glycol monomethyl ether, propylene glycol monomethyl ether acetate, etc.), esters (e.g., ethyl lactate, methyl acetate, butyl acetate, isoamyl acetate, ethyl lactate, methyl methoxypropionate, methyl hydroxyisobutyrate, etc.), and amides (e.g., dimethoxyacetamide, dimethylformamide, etc.). Examples of non-polar organic solvents include aromatic hydrocarbons (e.g., toluene, xylene, etc.). The solvents can be used alone or in combination of two or more. When two or more solvents are used, the total amount falls within the above range.

[0115] <Other ingredients> In addition to the above components, the resin composition of this embodiment may contain various polymeric compounds such as thermoplastic resins and their oligomers, as well as various additives. Examples of additives include ultraviolet absorbers, antioxidants, photopolymerization initiators, fluorescent brighteners, photosensitizers, dyes, pigments, thickeners, flow control agents, lubricants, antifoaming agents, leveling agents, gloss agents, and polymerization inhibitors. These additives may be used alone or in combination of two or more.

[0116] <Application> The resin composition of this embodiment is used as a cured product. Specifically, the resin composition of this embodiment can be suitably used as a low-dielectric-constant material and / or a low-dielectric-tangent material, such as an insulating layer for a printed wiring board, a semiconductor package material, or other electronic material resin composition. The resin composition of this embodiment can be suitably used as a material for prepregs, metal foil-clad laminates using prepregs, resin composite sheets, and printed wiring boards.

[0117] The resin composition of this embodiment preferably has a low dielectric constant (Dk) when molded into a cured plate with a thickness of 0.8 mm. Specifically, the dielectric constant (Dk) of the cured plate at 10 GHz measured according to a cavity resonator perturbation method is preferably 3.50 or less, more preferably 2.81 or less, and even more preferably 2.78 or less. There is no particular lower limit for the dielectric constant (Dk), but a value of 2.0 or more is practical, for example. Furthermore, the resin composition of this embodiment preferably has a low dielectric loss tangent (Df) when molded into a cured plate having a thickness of 0.8 mm. Specifically, the dielectric loss tangent (Df) at 10 GHz measured according to the cavity resonator perturbation method is preferably 0.0040 or less, more preferably 0.0030 or less, even more preferably 0.0020 or less, and even more preferably 0.0018 or less. There is no particular lower limit for the dielectric loss tangent (Df), but a value of 0.0001 or more is practical, for example. More specifically, the relative permittivity (Dk) and dielectric loss tangent (Df) of the cured sheet are measured by the method described in the examples below.

[0118] The resin composition of this embodiment is used as a layered material (including film and sheet forms) such as a prepreg or resin composite sheet that serves as an insulating layer for a printed wiring board. When used as such a layered material, the thickness is preferably 5 μm or more, more preferably 10 μm or more. The upper limit of the thickness is preferably 200 μm or less, more preferably 180 μm or less. Note that the thickness of the layered material refers to the thickness including the glass cloth when, for example, the resin composition of this embodiment is impregnated into glass cloth or the like. The material formed from the resin composition of the present embodiment may be used for applications in which a pattern is formed by exposure and development, or for applications in which no exposure and development is required. It is particularly suitable for applications in which no exposure and development is required.

[0119] <<Prepreg>> The prepreg of this embodiment is formed from a substrate (prepreg substrate) and the resin composition of this embodiment. The prepreg of this embodiment can be obtained, for example, by applying the resin composition of this embodiment to the substrate (e.g., by impregnation and / or coating) and then semi-curing by heating (e.g., by drying at 120 to 220°C for 2 to 15 minutes). In this case, the amount of the resin composition attached to the substrate, i.e., the amount of the resin composition (including the inorganic filler (B)) relative to the total amount of the semi-cured prepreg, is preferably in the range of 20 to 99% by mass, more preferably in the range of 20 to 80% by mass.

[0120] The substrate is not particularly limited as long as it is a substrate used in various printed wiring board materials. Examples of the substrate material include glass fibers (e.g., E-glass, D-glass, L-glass, S-glass, T-glass, Q-glass, UN-glass, NE-glass, spherical glass, etc.), inorganic fibers other than glass (e.g., quartz, etc.), and organic fibers (e.g., polyimide, polyamide, polyester, liquid crystal polyester, polytetrafluoroethylene, etc.). The form of the substrate is not particularly limited, and examples include woven fabric, nonwoven fabric, roving, chopped strand mat, surfacing mat, etc. These substrates may be used alone or in combination of two or more. Among these substrates, woven fabrics that have been subjected to an ultra-opening treatment and a clogging treatment are preferred from the viewpoint of dimensional stability. From the viewpoint of strength and low water absorption, the substrate should have a thickness of 200 μm or less and a mass of 250 g / m. 2 The following glass woven fabrics are preferred, and from the viewpoint of moisture absorption and heat resistance, glass woven fabrics that have been surface-treated with a silane coupling agent such as epoxy silane or amino silane are preferred. From the viewpoint of electrical properties, low-dielectric glass cloths made of glass fibers that exhibit a low relative dielectric constant and a low dielectric loss tangent, such as L-glass, NE-glass, or Q-glass, are more preferred. An example of a substrate with a low relative dielectric constant is a substrate with a relative dielectric constant of 5.0 or less (preferably 3.0 to 4.9). An example of a substrate with a low dielectric loss tangent is a substrate with a dielectric loss tangent of 0.006 or less (preferably 0.001 to 0.005). The relative dielectric constant and dielectric loss tangent are values ​​measured at 10 GHz using a perturbation method cavity resonator.

[0121] <<Metal foil clad laminate>> The metal foil-clad laminate of this embodiment includes at least one layer formed from the prepreg of this embodiment and a metal foil disposed on one or both sides of the layer formed from the prepreg. Examples of methods for producing the metal foil-clad laminate of this embodiment include a method in which at least one prepreg of this embodiment (preferably two or more prepregs) is disposed, and a metal foil is disposed on one or both sides of the prepreg, followed by lamination molding. More specifically, the laminate can be produced by disposing a metal foil, such as copper or aluminum, on one or both sides of the prepreg, followed by lamination molding. The number of prepregs is preferably 1 to 10, more preferably 2 to 10, and even more preferably 2 to 9. The metal foil may be any foil suitable for use in printed wiring boards, and examples thereof include copper foils such as rolled copper foil and electrolytic copper foil. The thickness of the metal foil (preferably copper foil) is not particularly limited and may be approximately 1.5 to 70 μm. Examples of molding methods include methods commonly used for molding laminates for printed wiring boards. More specifically, methods using a multi-stage press, multi-stage vacuum press, continuous molding machine, autoclave molding machine, etc. are used, at a temperature of about 180 to 350°C, for a heating time of about 100 to 300 minutes, and a surface pressure of 20 to 100 kg / cm. 2 Examples of suitable methods include lamination molding at approximately the same thickness. A multilayer board can also be produced by combining the prepreg of this embodiment with a separately prepared inner layer wiring board and laminating it together. A method for producing a multilayer board involves, for example, placing copper foil of approximately 35 μm on both sides of a single prepreg of this embodiment, laminating it using the above-described molding method, forming an inner layer circuit, and then blackening the circuit to form an inner layer circuit board. Then, the inner layer circuit board and the prepreg of this embodiment are alternately arranged one by one, and copper foil is placed on the outermost layer. The multilayer board can be produced by laminating and molding it under the above-described conditions, preferably under vacuum. The metal foil-clad laminate of this embodiment can be suitably used as a printed wiring board.

[0122] The metal foil-clad laminate of this embodiment preferably also has a low water absorption rate after being left to stand for 5 hours in the presence of saturated steam at 121°C and 2 atmospheres (PCT treatment: moisture absorption treatment using a pressure cooker tester). Specifically, the water absorption rate of the cured product, which is subjected to PCT treatment at 121°C for 5 hours after removing the metal foil by etching, is preferably 2.00% by mass or less, more preferably 1.80% by mass or less, even more preferably 1.50% by mass or less, and particularly preferably 1.30% by mass or less. The lower limit is not particularly limited, but is, for example, 0.10% by mass or more.

[0123] Furthermore, it is preferable that the cured sheet from which the metal foil has been removed by etching has a low dielectric constant (Dk) after undergoing PCT treatment at 121°C and 2 atmospheres in the presence of saturated water vapor for 5 hours. Specifically, the Dk after the PCT treatment is preferably 3.50 or less, more preferably 3.30 or less, and even more preferably 3.20 or less. The lower limit is not particularly limited, but is, for example, 2.00 or more. Furthermore, it is preferable that the dielectric loss tangent (Df) after PCT treatment of the cured sheet from which the metal foil has been removed by etching at 121°C for 5 hours in the presence of saturated water vapor at 2 atmospheres is low. Specifically, the Df after the PCT treatment is preferably 0.0150 or less, more preferably 0.0120 or less, even more preferably 0.0110 or less, and particularly preferably 0.0100 or less. The lower limit is not particularly limited, but is, for example, 0.0050 or more. The relative permittivity (Dk) and dielectric loss tangent (Df) and the PCT treatment are as described in the examples below.

[0124] As described above, the resin composition for electronic materials obtained using the resin composition of this embodiment (a resin composition consisting of a combination of specific components) can provide a cured product that has excellent dielectric properties, moisture absorption heat resistance, and dielectric properties after moisture absorption treatment. It is also possible to provide a resin composition with low water absorption.

[0125] <<Printed wiring boards>> The printed wiring board of this embodiment includes an insulating layer and a conductor layer disposed on the surface of the insulating layer, wherein the insulating layer includes at least one of a layer formed from the resin composition of this embodiment and a layer formed from the prepreg of this embodiment. Such a printed wiring board can be manufactured using conventional methods, and the manufacturing method is not particularly limited. An example of a method for manufacturing a printed wiring board is described below. First, a metal foil-clad laminate such as the metal foil-clad laminate described above is prepared. Next, the surface of the metal foil-clad laminate is etched to form an inner layer circuit, thereby producing an inner layer substrate. If necessary, the surface of the inner layer circuit of this inner layer substrate is subjected to a surface treatment to increase adhesive strength. Next, a required number of the prepregs described above are stacked on the surface of the inner layer circuit, and metal foil for an outer layer circuit is further laminated on the outside, followed by heating and pressurizing to form an integral mold. In this way, a multilayer laminate is manufactured, in which an insulating layer consisting of a substrate and a cured product of the resin composition is formed between the inner layer circuit and the metal foil for the outer layer circuit. Next, this multilayer laminate is subjected to drilling processing for through holes and via holes, and then a plated metal film is formed on the wall surface of the hole to provide electrical continuity between the inner layer circuit and the metal foil for the outer layer circuit.The metal foil for the outer layer circuit is then etched to form the outer layer circuit, thereby producing a printed wiring board.

[0126] The printed wiring board obtained in the above manufacturing example has an insulating layer and a conductor layer formed on the surface of this insulating layer, and the insulating layer contains the resin composition of this embodiment described above and / or its cured product. That is, the prepreg of this embodiment described above (for example, a prepreg formed from a base material and the resin composition of this embodiment impregnated or applied thereto), or the layer formed from the resin composition of the metal foil-clad laminate of this embodiment described above, serves as the insulating layer of this embodiment. The present embodiment relates to a semiconductor device including the printed wiring board. For details of the semiconductor device, please refer to paragraphs 0200 to 0202 of Japanese Patent Laid-Open No. 2021-021027, the contents of which are incorporated herein by reference.

[0127] <<Resin composite sheet>> The resin composite sheet of this embodiment includes a support and a layer formed from the resin composition of this embodiment and disposed on the surface of the support. The resin composite sheet can be used as a build-up film or a dry film solder resist. There are no particular limitations on the method for producing the resin composite sheet, but an example of a method for obtaining the resin composite sheet includes applying (coating) a solution obtained by dissolving the resin composition of this embodiment in a solvent to a support and drying the applied solution.

[0128] Examples of the support used here include, but are not limited to, polyethylene film, polypropylene film, polycarbonate film, polyethylene terephthalate film, ethylene tetrafluoroethylene copolymer film, and release films obtained by applying a release agent to the surface of these films, organic film substrates such as polyimide film, conductive foils such as copper foil and aluminum foil, glass plates, SUS (Steel Use Stainless) plates, FRP (Fiber-Reinforced Plastics), and other plate-shaped materials.

[0129] Examples of application methods (coating methods) include methods in which a solution of the resin composition of this embodiment dissolved in a solvent is applied onto a support using a bar coater, die coater, doctor blade, baker applicator, or the like. Furthermore, after drying, a single-layer sheet can be obtained by peeling or etching the support from a resin composite sheet in which the support and the resin composition are laminated. It should be noted that a single-layer sheet can also be obtained without using a support by supplying a solution of the resin composition of this embodiment dissolved in a solvent into a mold having a sheet-shaped cavity and drying it to form it into a sheet.

[0130] In the production of the monolayer sheet or resin composite sheet of this embodiment, the drying conditions for removing the solvent are not particularly limited. However, because low temperatures tend to leave the solvent in the resin composition, and high temperatures accelerate curing of the resin composition, a temperature of 20°C to 200°C for 1 to 90 minutes is preferred. The monolayer sheet or resin composite sheet can be used in an uncured state after the solvent has been dried, or it can be used in a semi-cured (B-staged) state as needed. Furthermore, the thickness of the resin layer in the monolayer sheet or resin composite sheet of this embodiment can be adjusted by the concentration and coating thickness of the solution of the resin composition of this embodiment used for coating (coating). While not particularly limited, a thickness of 0.1 to 500 μm is preferred because a thicker coating generally tends to leave the solvent during drying. [Example]

[0131] The present invention will be explained in more detail below with reference to examples. The materials, amounts used, ratios, processing details, processing procedures, etc. shown in the following examples can be appropriately changed without departing from the spirit of the present invention. Therefore, the scope of the present invention is not limited to the specific examples shown below. If the measuring instruments used in the examples are difficult to obtain due to discontinuation or the like, measurements can be made using other instruments with equivalent performance.

[0132] <Synthesis Example 1: Synthesis of polymer (va) having a structural unit represented by formula (V)> 2.25 moles (292.9 g) of divinylbenzene, 1.32 moles (172.0 g) of ethylvinylbenzene, 11.43 moles (1190.3 g) of styrene, and 15.0 moles (1532.0 g) of n-propyl acetate were charged into a reactor, and 600 mmol of boron trifluoride diethyl ether complex was added at 70 °C. The reaction was allowed to proceed for 4 hours. After the polymerization reaction was terminated with aqueous sodium bicarbonate, the oil layer was washed three times with pure water and devolatilized under reduced pressure at 60 °C to recover polymer (va) having structural units represented by formula (V). The resulting polymer (va) having structural units represented by formula (V) was weighed, confirming that 860.8 g of polymer (va) having structural units represented by formula (V) was obtained.

[0133] The resulting polymer (va) having a structural unit represented by formula (V) had a number average molecular weight Mn of 2,060, a weight average molecular weight Mw of 30,700, and a monodispersity index Mw / Mn of 14.9. 13 C-NMR and 1 By performing H-NMR analysis, resonance lines derived from each monomer unit used as a raw material were observed in the polymer (va) having a structural unit represented by formula (V). Based on the NMR measurement results and GC analysis results, the proportion of each monomer unit (structural unit derived from each raw material) in the polymer (va) having a structural unit represented by formula (V) was calculated as follows: Structural units derived from divinylbenzene: 20.9 mol% (24.3 mass%) Structural units derived from ethylvinylbenzene: 9.1 mol% (10.7 mass%) Structural units derived from styrene: 70.0 mol% (65.0 mass%) Furthermore, the content of structural units having residual vinyl groups derived from divinylbenzene was 16.7 mol % (18.5 mass %).

[0134] <Synthesis Example 2: Synthesis of α-naphthol aralkyl cyanate ester compound (SNCN)> 0.47 mol (OH group equivalent) of α-naphthol aralkyl resin (SN495V, OH group equivalent: 236 g / eq., manufactured by Nippon Steel Chemical Co., Ltd.; the number of naphthol aralkyl repeating units ranges from 1 to 5) was dissolved in 500 mL of chloroform, and 0.7 mol of triethylamine was added to this solution to prepare Solution 1. While maintaining the temperature at -10°C, Solution 1 was added dropwise over 1.5 hours to 300 g of a chloroform solution of 0.93 mol of cyanogen chloride placed in a reactor. After the addition was complete, the mixture was stirred for 30 minutes. A mixed solution of 0.1 mol of triethylamine and 30 g of chloroform was then added dropwise to the reactor, and the mixture was stirred for 30 minutes to complete the reaction. The by-product triethylamine hydrochloride was filtered off from the reaction solution, and the resulting filtrate was washed with 500 mL of 0.1 N hydrochloric acid and then with 500 mL of water four times. This was dried over sodium sulfate, evaporated at 75°C, and further degassed under reduced pressure at 90°C to obtain a brown solid α-naphthol aralkyl cyanate ester compound represented by formula (S1) (R C1 ~R C4 are all hydrogen atoms, and n c The compound was a mixture of 1 to 5. The obtained α-naphthol aralkyl cyanate ester compound was analyzed by infrared absorption spectroscopy, and found to have a peak at 2264 cm -1 Absorption of cyanate ester groups was confirmed in the vicinity. [ka]

[0135] <Synthesis Example 3: Synthesis of modified polyphenylene ether compound> <<Synthesis of Difunctional Phenylene Ether Oligomers>> A 12 L vertical reactor equipped with a stirrer, a thermometer, an air inlet tube, and a baffle plate was charged with 29.36 g (42.1 mmol) of CuBr, 1.81 g (10.5 mmol) of N,N'-di-t-butylethylenediamine, 67.77 g (671.0 mmol) of n-butyldimethylamine, and 2,600 g of toluene. The mixture was stirred at a reaction temperature of 40°C. 2,2',3,3',5,5'-hexamethyl-(1,1', A mixed solution of 129.32 g (0.48 mol) N,N'-di-t-butylethylenediamine (N,N'-biphenol), 878.4 g (7.2 mol) 2,6-dimethylphenol, 1.22 g (7.2 mmol) N,N'-di-t-butylethylenediamine, and 26.35 g (260.9 mmol) n-butyldimethylamine was added dropwise over 230 minutes while bubbling a mixed gas (nitrogen and air) adjusted to an oxygen concentration of 8% by volume at a flow rate of 5.2 L / min and stirring was continued. After the addition was completed, 1,500 g of water containing 48.06 g (126.4 mmol) of tetrasodium ethylenediaminetetraacetate was added to quench the reaction. The aqueous and organic layers were separated, and the organic layer was washed with 1 N aqueous hydrochloric acid and then with pure water. The resulting solution was concentrated to 50% by mass using an evaporator to obtain 1,981 g of a toluene solution of a bifunctional phenylene ether oligomer (Resin "A"). The number average molecular weight of Resin "A" measured by GPC in terms of polystyrene was 1,975, the weight average molecular weight measured by GPC in terms of polystyrene was 3,514, and the hydroxyl equivalent was 990.

[0136] <<Synthesis of modified polyphenylene ether compounds>> A reactor equipped with a stirrer, thermometer, and reflux condenser was charged with 833.4 g of a toluene solution of resin "A," 76.7 g of vinylbenzyl chloride (AGC Seimi Chemical Co., Ltd., "CMS-P"), 1,600 g of methylene chloride, 6.2 g of benzyldimethylamine, 199.5 g of purified water, and 83.6 g of a 30.5 wt% aqueous solution of NaOH. The mixture was stirred at 40°C. After 24 hours of stirring, the organic layer was washed with 1N aqueous hydrochloric acid and then purified water. The resulting solution was concentrated using an evaporator and added dropwise to methanol to solidify. The solid was recovered by filtration and vacuum dried to obtain 450.1 g of a modified polyphenylene ether compound. The modified polyphenylene ether compound had a number average molecular weight (Mw) of 2,250 (based on polystyrene standards) by GPC, a weight average Mw of 3,920 (based on polystyrene standards) by GPC, and a vinyl group equivalent of 1,189 g / vinyl group.

[0137] <Measurement of weight average molecular weight and number average molecular weight> The weight-average molecular weight and number-average molecular weight were measured by gel permeation chromatography (GPC) using a pump (Shimadzu Corporation, LC-20AD), a refractive index detector (Shimadzu Corporation, RID-10A), and GPC columns (Showa Denko K.K., GPC KF-801, 802, 803, 804) with tetrahydrofuran as the solvent, a flow rate of 1.0 mL / min, a column temperature of 40°C, and a calibration curve based on monodisperse polystyrene.

[0138] Example 1 5 parts by mass of a maleimide compound (MIR-3000-70MT, manufactured by Nippon Kayaku Co., Ltd., corresponding to the compound represented by formula (M3)), 29 parts by mass of a maleimide compound (ma) shown in the structure below (NE-X-9470S, manufactured by DIC Corporation, corresponding to the compound represented by formula (M1)), 30 parts by mass of the polymer (va) having a structural unit represented by formula (V) obtained in Synthesis Example 1, 15 parts by mass of a hydrogenated styrene-based thermoplastic elastomer (SEBS, block copolymer, SEPTON2104, Mn83000, manufactured by Kuraray Co., Ltd.), 15 parts by mass of a cyanate ester compound (α-naphthol aralkyl cyanate ester compound (S A varnish was obtained by dissolving and dispersing 5 parts by weight of a phosphate-based flame retardant (PX-200, Daihachi Chemical Industry Co., Ltd.), 15 parts by weight of N-phenylmaleimide (Tokyo Chemical Industry Co., Ltd., product number P0900), 0.3 parts by weight of a wetting and dispersing agent (BYK Corporation, BYK-2009), 0.5 parts by weight of a wetting and dispersing agent (DISPERBYK-161, BYK Japan Co., Ltd.), and 100 parts by weight of a methyl ethyl ketone (MEK) slurry of vinylsilane-treated silica (SC2050MNU (trade name), median diameter 0.5 μm, nonvolatile content 70% by weight, Admatechs Co., Ltd.). The amounts of each additive listed above indicate the solid content. The vinylsilane-treated silica corresponds to the inorganic filler (B) containing an organic group containing a carbon-carbon unsaturated bond.

[0139] Maleimide compounds (MA) [ka] n is an integer of 1 to 20.

[0140] <Production of hardened plate test pieces with a thickness of 0.8 mm> The solvent was evaporated from the resulting varnish to obtain a mixed resin powder. The mixed resin powder was filled into a mold with a side length of 100 mm and a thickness of 0.8 mm, and 12 μm copper foil (3EC-M2S-VLP, manufactured by Mitsui Mining & Smelting Co., Ltd.) was placed on both sides. A pressure of 30 kg / cm was applied. 2 The mixture was vacuum pressed at 220°C for 120 minutes to obtain a hardened plate with a side length of 100 mm and a thickness of 0.8 mm. The obtained cured sheets were evaluated for the dielectric constant (Dk), dielectric loss tangent (Df), water absorption rate after PCT treatment (described later), dielectric constant (Dk) and dielectric loss tangent (Df) after PCT treatment, and moisture absorption and heat resistance. The evaluation results are shown in Table 1.

[0141] <Measurement and evaluation methods> (1) Dielectric constant (Dk) and dielectric loss tangent (Df) The copper foil of the cured sheet was removed by etching, and the sheet was dried at 120°C for 60 minutes. The relative permittivity (Dk) and dielectric loss tangent (Df) of the dried sheet were measured at 10 GHz using a perturbation cavity resonator. The measurement temperature was 23°C. The perturbation method cavity resonator used was Agilent8722ES manufactured by Agilent Technologies. The evaluation was as follows: (Dk) A: 2.78 or less B: More than 2.78 but less than 2.81 C: over 2.81 (Df) A:0.0020 or less B: More than 0.0020

[0142] (2) PCT treatment (moisture absorption treatment using a pressure cooker tester) The copper foil of the cured sheet was removed by etching, and the sheet was left to stand for 5 hours in the presence of saturated steam at 121°C and 2 atmospheres using a pressure cooker tester. Thereafter, Dk and Df after PCT treatment (Dk and Df after moisture absorption) were measured in the same manner as above. The pressure cooker tester used was a PC-3 model manufactured by Hirayama Seisakusho Co., Ltd. The evaluation was as follows: (Dk after PCT processing) A: 3.20 or less B: Over 3.20 (Df after PCT processing) A: 0.0110 or less B: More than 0.0110 The copper foil of the cured sheet was removed by etching to obtain a sample for water absorption measurement. The obtained sample was dried at 120°C for 60 minutes, and then the mass of the sample before PCT treatment was measured. The sample whose mass was measured was left to stand for 5 hours in the presence of saturated steam at 121°C and 2 atmospheres using a pressure cooker tester, and then the mass of the sample after PCT treatment was measured. The water absorption of the sample for water absorption measurement after PCT treatment was calculated using the following formula. [(mass of sample after PCT treatment - mass of sample before PCT treatment) / mass of sample before PCT treatment] x 100 (unit: mass%) (Water absorption rate after PCT treatment) A: 1.30% by mass or less B: More than 1.30% by mass (Moisture absorption heat resistance) The cured sheets were cut to 50 mm x 50 mm (downsized), and the copper foil on one side was completely removed by etching. Half of the copper foil on the other side was also removed by etching to obtain samples for measuring moisture absorption and heat resistance. The resulting samples were dried at 120°C for 60 minutes, then left to stand in saturated steam at 121°C and 2 atmospheres for 5 hours using a pressure cooker tester. They were then immersed in a solder bath at 260°C for 30 seconds and visually inspected for any abnormalities. Three samples were tested for each measurement. A rating of "A" was given for zero abnormalities, a rating of "B" for one to two abnormalities, and a rating of "C" for three abnormalities. The appearance was evaluated by a majority vote of five experts.

[0143] Example 2 The same procedures were carried out as in Example 1, except that the methyl ethyl ketone slurry of vinylsilane-treated silica was replaced with the same amount of another methyl ethyl ketone slurry of vinylsilane-treated silica (5SV-CM8, manufactured by Admattex Co., Ltd.).

[0144] Example 3 In Example 1, the amount of polymer (va) having a structural unit represented by formula (V) was changed to 10 parts by mass, and 20 parts by mass of the modified polyphenylene ether compound synthesized in Synthesis Example 3 was added, but the rest was the same.

[0145] Comparative Example 1 The same procedures were carried out as in Example 1, except that the methyl ethyl ketone slurry of vinylsilane-treated silica was replaced with the same amount of methyl ethyl ketone slurry of epoxysilane-treated silica (manufactured by Admattex Co., Ltd., SC2050MB).

[0146] Comparative Example 2 53 parts by mass of the polymer (va) having the structural unit represented by formula (V) obtained in Synthesis Example 1, 32 parts by mass of hydrogenated styrene-based thermoplastic elastomer (SEPTON2104), 15 parts by mass of phosphorus-based flame retardant (PX-200), 0.3 parts by mass of wetting and dispersing agent (BYK-2009), 0.5 parts by mass of wetting and dispersing agent (DISPERBYK-161), and 100 parts by mass of vinylsilane-treated silica methyl ethyl ketone (MEK) slurry (SC2050MNU) were dissolved and dispersed in methyl ethyl ketone and mixed to obtain a varnish. Evaluation was performed in the same manner as in Example 1.

[0147] [Table 1]

Claims

1. A polymer (A) having a structural unit represented by formula (V), An inorganic filler (B) containing an organic group having a carbon-carbon unsaturated bond, And another thermosetting compound (C) not corresponding to the polymer (A) and the inorganic filler (B), The equivalent weight of the vinyl group of the polymer (A) is 200 g / eq or more and 1200 g / eq or less, Among the inorganic fillers (B), a compound containing an organic group having a carbon-carbon unsaturated bond is defined as compound (b1), and the inorganic filler excluding the organic group having a carbon-carbon unsaturated bond from the inorganic filler (B) is defined as inorganic filler (b2). A resin composition wherein the number of functional groups of the compound (b1) is more than 1 times and 5 times or less the number of functional groups of the inorganic filler (b2), Based on 100 parts by mass of the resin solid content in the resin composition, The content of the polymer (A) is 5 to 70 parts by mass, The content of the inorganic filler (D) is 10 to 500 parts by mass, The content of the other thermosetting compound (C) is 5 to 95 parts by mass, The relative dielectric constant (Dk) of the cured plate at a frequency of 10 GHz measured according to the cavity resonator perturbation method when the resin composition is formed into a cured plate with a thickness of 0.8 mm is 3.50 or less, and the dielectric loss tangent (Df) at a frequency of 10 GHz measured according to the cavity resonator perturbation method is 0.0040 or less. A resin composition. 【Chemical Formula 1】 (In formula (V), Ar represents an aromatic hydrocarbon linking group. * represents the bonding position.)

2. The resin composition according to claim 1, wherein the weight average molecular weight of the polymer (A) is 1,000 to 160,000.

3. The organic group containing a carbon-carbon unsaturated bond has a CH ２ =C(X)-(X is a hydrogen atom or a methyl group) structure. The resin composition according to claim 1.

4. The resin composition according to claim 1, wherein the organic group containing a carbon-carbon unsaturated bond is one selected from the group consisting of a vinyl group, an allyl group, an acrylic group, and a methacrylic group.

5. The resin composition according to claim 1, wherein the molecular weight of the compound (B) is 70 to 500.

6. The resin composition according to claim 1, wherein the boiling point of the compound (B) is 110 to 300 °C.

7. The resin composition according to claim 1, wherein the content of the compound (B) relative to 100 parts by mass of the resin solid content in the resin composition is 1 to 10 parts by mass.

8. The resin composition according to claim 1, wherein the mass ratio of the polymer (A) to the compound (B) in the resin composition is 1:0.025 to 0.

7.

9. The resin composition according to claim 1, wherein the other thermosetting compound (C) contains at least one selected from the group consisting of a maleimide compound, a polyphenylene ether compound containing two or more carbon-carbon unsaturated double bonds, a cyanate ester compound, an epoxy compound, a phenol compound, an alkenyl-substituted nadimide compound, an oxetane resin, and a benzoxazine compound.

10. The resin composition according to claim 1, wherein the other thermosetting compound (C) contains at least one selected from the group consisting of a compound (M1) represented by formula (M1), a compound represented by formula (M3), a compound represented by formula (M5), and a compound represented by formula (OP-1). 【Chemical formula 2】 (In formula (M1), R Ｍ１ , R Ｍ２ , R Ｍ３ , and R Ｍ４ each independently represent a hydrogen atom or an organic group. R Ｍ５ and R Ｍ６ each independently represent a hydrogen atom or an alkyl group. Ar Ｍ represents a divalent aromatic group. A is an alicyclic group having 4 to 6 members. R Ｍ７ and R Ｍ８ are each independently an alkyl group. mx is 1 or 2, and lx is 0 or 1. R Ｍ９ and R Ｍ１０ each independently represents a hydrogen atom or an alkyl group. R Ｍ１１ , R Ｍ１２ , R Ｍ１３ , and R Ｍ１４ each independently represents a hydrogen atom or an organic group. R Ｍ１５ each independently represents an alkyl group having 1 to 10 carbon atoms, an alkyloxy group having 1 to 10 carbon atoms, an alkylthio group having 1 to 10 carbon atoms, an aryl group having 6 to 10 carbon atoms, an aryloxy group having 1 to 10 carbon atoms, an arylthio group having 1 to 10 carbon atoms, a halogen atom, a hydroxyl group, or a mercapto group. px represents an integer of 0 to 3. nx represents an integer of 1 to 20.) [Chemical Formula 3] (In formula (M3), R ５５ each independently represents a hydrogen atom, an alkyl group having 1 to 8 carbon atoms, or a phenyl group, and n ５ represents an integer of 1 or more and 10 or less.) [Chemical Formula 4] (In formula (M5), R ５８ each independently represents a hydrogen atom, an alkyl group having 1 to 8 carbon atoms, or a phenyl group, R ５９ each independently represents a hydrogen atom or a methyl group, and n ６ represents an integer of 1 or more.) [Chemical Formula 5] (In formula (OP-1), X represents an aromatic group, -(Y-O)n ２ - represents a polyphenylene ether structure, R １ , R ２ , and, R ３ each independently represents a hydrogen atom, an alkyl group, an alkenyl group, or an alkynyl group, n １ represents an integer of 1 to 6, n ２ represents an integer of 1 to 100, and n ３ represents an integer of 2 to 4.) Claim 11 The resin composition according to claim 1, wherein the other thermosetting compound (C) contains at least one selected from the group consisting of a compound (M1) represented by formula (M1), a compound represented by formula (M3), and a compound represented by formula (OP-1). 【Chemical Formula 6】 (In formula (M1), R Ｍ１ , R Ｍ２ , R Ｍ３ , and R Ｍ４ each independently represent a hydrogen atom or an organic group. R Ｍ５ and R Ｍ６ each independently represent a hydrogen atom or an alkyl group. Ar Ｍ represents a divalent aromatic group. A is an alicyclic group having 4 to 6 members. R Ｍ７ and R Ｍ８ are each independently an alkyl group. mx is 1 or 2, and lx is 0 or 1. R Ｍ９ and R Ｍ１０ each independently represent a hydrogen atom or an alkyl group. R Ｍ１１ , R Ｍ１２ , R Ｍ１３ , and R Ｍ１４ each independently represent a hydrogen atom or an organic group. R Ｍ１５ each independently represent an alkyl group having 1 to 10 carbon atoms, an alkyloxy group having 1 to 10 carbon atoms, an alkylthio group having 1 to 10 carbon atoms, an aryl group having 6 to 10 carbon atoms, an aryloxy group having 1 to 10 carbon atoms, an arylthio group having 1 to 10 carbon atoms, a halogen atom, a hydroxyl group, or a mercapto group. px represents an integer from 0 to 3. nx represents an integer from 1 to 20.) 【Chemical Formula 7】 (In formula (M3), R ５５ each independently represent a hydrogen atom, an alkyl group having 1 to 8 carbon atoms, or a phenyl group, and n ５ represents an integer from 1 to 10.) 【Chemical Formula 8】 (In formula (OP-1), X represents an aromatic group, -(Y-O)n ２ - represents a polyphenylene ether structure, and R １ , R ２, and R ３ each independently represents a hydrogen atom, an alkyl group, an alkenyl group or an alkynyl group, and n １ represents an integer of 1 to 6, and n ２ represents an integer of 1 to 100, and n ３ represents an integer of 2 to 4. )

12. The resin composition according to claim 1, wherein the other thermosetting compound (C) contains at least one selected from the group consisting of compounds represented by the formula (OP-1), and the content thereof is 3 to 50 parts by mass with respect to 100 parts by mass of the resin solid content in the resin composition. 【Chemical formula 9】 (In the formula (OP-1), X represents an aromatic group, and -(Y-О)n ２ - represents a polyphenylene ether structure, and R １ , R ２ , and R ３ each independently represents a hydrogen atom, an alkyl group, an alkenyl group or an alkynyl group, and n １ represents an integer of 1 to 6, and n ２ represents an integer of 1 to 100, and n ３ represents an integer of 2 to 4. )

13. The resin composition according to claim 1, which substantially does not contain a polymerization initiator.

14. The polymer (A) contains a structural unit (a) derived from a divinyl aromatic compound in a proportion of 3 mol% or more and 40 mol% or less, and among all the structural units excluding the terminals, the structural units containing an aromatic ring are 90 mol% or more. The resin composition according to claim 1.

15. The weight average molecular weight of the polymer (A) is 1,000 to 160,000, the organic group containing a carbon-carbon unsaturated bond is one selected from the group consisting of a vinyl group, an allyl group, an acrylic group, and a methacrylic group, the molecular weight of the compound (B) is 70 to 500, the boiling point of the compound (B) is 110 to 300 °C, The content of the compound (B) is 1 to 10 parts by mass with respect to 100 parts by mass of the resin solid content in the resin composition, The mass ratio of the polymer (A) and the compound (B) in the resin composition is 1:0.025 to 0.7, The other thermosetting compound (C) includes at least one selected from the group consisting of a maleimide compound, a polyphenylene ether compound containing two or more carbon-carbon unsaturated double bonds, a cyanate ester compound, an epoxy compound, a phenol compound, an alkenyl-substituted nadimide compound, an oxetane resin, and a benzoxazine compound, The resin composition according to claim 1.

16. The other thermosetting compound (C) includes at least one selected from the group consisting of compounds represented by the formula (OP-1), and its content is 3 to 50 parts by mass with respect to 100 parts by mass of the resin solid content in the resin composition. The resin composition according to claim 15. 【Chemical formula 10】 (In the formula (OP-1), X represents an aromatic group, and -(Y-О)n ２ - represents a polyphenylene ether structure, and R １ , R ２ , and R ３ each independently represents a hydrogen atom, an alkyl group, an alkenyl group, or an alkynyl group, and n １ represents an integer from 1 to 6, n ２ represents an integer from 1 to 100, and n ３ represents an integer from 2 to 4.)

17. The resin composition according to claim 15, which substantially does not contain a polymerization initiator.

18. A prepreg formed from a base material and the resin composition according to any one of claims 1 to 17.

19. A metal foil-clad laminate including at least one layer formed from the prepreg according to claim 18 and a metal foil disposed on one or both sides of the layer formed from the prepreg.

20. A resin composite sheet including a support and a layer formed from the resin composition according to any one of claims 1 to 17 disposed on the surface of the support.

21. A printed wiring board including an insulating layer and a conductor layer disposed on the surface of the insulating layer, wherein the insulating layer includes a layer formed from the resin composition according to any one of claims 1 to 17.

22. A semiconductor device including the printed wiring board according to claim 21.

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