JP7380944B2 - Resin compositions, prepregs, metal foil laminates, resin composite sheets, printed wiring boards, and semiconductor devices - Google Patents

Description

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.

In recent years, the integration and miniaturization of semiconductor elements used in mobile terminals, electronic equipment, communication equipment, etc. have been accelerating. Along with this, there is a need for technology that enables high-density packaging of semiconductor elements, and improvements are also needed for printed wiring boards, which play an important role.
On the other hand, the uses of electronic devices, etc. continue to diversify and expand. In response to this trend, the characteristics required of printed wiring boards, metal foil-clad laminates, prepregs, etc. used therein are becoming more diverse and demanding. Taking these required characteristics into consideration, various materials and processing methods have been proposed to obtain improved printed wiring boards. One example of this is the development and improvement of resin materials that make up prepregs and resin composite sheets.
For example, Patent Document 1 describes a novel soluble polyfunctional vinyl aromatic copolymer with improved heat resistance, compatibility, transparency, and toughness, a method for producing the same, and a curable composition containing the copolymer. is disclosed.

International Publication No. 2017/115813

As mentioned above, the uses of electronic devices and the like continue to diversify and expand, and there is a demand for new resin materials for prepregs and the like. In particular, further material development is required regarding resin compositions with excellent dielectric properties.
The present invention aims to solve the above problems, and provides a novel resin composition with excellent dielectric properties, a prepreg, a metal foil-clad laminate, a resin composite sheet, a printed wiring board, and The purpose is to provide semiconductor devices.

Based on the above-mentioned problems, the present inventor has conducted studies and found that the above-mentioned problems can be solved by blending an inorganic filler containing an organic group containing a carbon-carbon unsaturated bond into a predetermined aromatic vinyl polymer. I found a solution.
Specifically, the above problem was solved by the following means.
<1> 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, the polymer (A) and A resin composition containing another thermosetting compound (C) that does not fall under the inorganic filler (B).
(In formula (V), Ar represents an aromatic hydrocarbon linking group. * represents the bonding position.)
<2> The resin composition according to <1>, wherein the polymer (A) has a weight average molecular weight of 1,000 to 160,000.
<3> The resin composition according to <1> or <2>, wherein the content of the polymer (A) is 5 to 70 parts by mass based on 100 parts by mass of resin solids in the resin composition.
<4> Any one of <1> to <3>, wherein the organic group containing a carbon-carbon unsaturated bond has a structure of CH ₂ =C(X)- (X is a hydrogen atom or a methyl group) The resin composition described in .
<5> The organic group containing a carbon-carbon unsaturated bond includes at least one selected from the group consisting of a vinyl group, an allyl group, an acrylic group, and a methacryl group. The resin composition according to any one of the above.
<6> The inorganic filler (B) is any one of <1> to <5>, wherein the organic group containing the carbon-carbon unsaturated bond is bonded via a silicon atom. The resin composition described in .
<7> The inorganic filler (B) is selected from the group consisting of silica, aluminum hydroxide, aluminum nitride, boron nitride, forsterite, titanium oxide, barium titanate, strontium titanate, and calcium titanate. The resin composition according to any one of <1> to <6>, containing one or more types.
<8> The resin composition according to any one of <1> to <6>, wherein the inorganic filler (B) contains silica.
<9> The inorganic filler (B) of <1> to <6>, wherein the inorganic filler (B) is obtained by reacting the organosilicon compound having an organic group containing a carbon-carbon unsaturated bond with silica in a slurry state. The resin composition according to any one of the above.
<10> Any one of <1> to <9>, wherein the content of the inorganic filler (B) is 10 to 500 parts by mass relative to 100 parts by mass of resin solids in the resin composition. The resin composition described.
<11> The other thermosetting compound (C) is 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, The resin composition according to any one of <1> to <10>, comprising at least one selected from the group consisting of an oxetane resin and a benzoxazine compound.
<12> The other thermosetting compound (C) is a compound represented by formula (M1), a compound represented by formula (M3), a compound represented by formula (M5), and The resin composition according to any one of <1> to <11>, containing at least one selected from the group consisting of compounds represented by formula (OP-1).
(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 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 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 represents 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, or an aryl group having 6 to 10 carbon atoms. , represents 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. )
(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 to 10.)
(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 greater than or equal to 1.)
(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 are 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.)
<13> The other thermosetting compound (C) is a compound (M1) represented by formula (M1), a compound represented by formula (M3), and a compound represented by formula (OP-1) The resin composition according to any one of <1> to <11>, containing at least one selected from the group consisting of compounds.
(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 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 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 represents 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, or an aryl group having 6 to 10 carbon atoms. , represents 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. )
(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 to 10.)
(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 are 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.)
<14> Any one of <1> to <13>, wherein the content of the thermosetting compound (C) is 5 to 95 parts by mass relative to 100 parts by mass of resin solids in the resin composition. The resin composition described in .
<15> Based on 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 resin composition according to any one of <1> to <14>, wherein the content of the thermosetting compound (C) is 5 to 95 parts by mass.
<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 with respect to 100 parts by mass of resin solid content in the resin composition,
The organic group containing a carbon-carbon unsaturated bond includes at least one selected from the group consisting of a vinyl group, an allyl group, an acrylic group, and a methacryl group,
The inorganic filler (B) is an inorganic filler in which the organic group containing the 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 with respect to 100 parts by mass of resin solid content in the resin composition,
The other thermosetting compound (C) is 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 at least one selected from the group consisting of benzoxazine compounds,
The resin composition according to <1>, wherein the content of the thermosetting compound (C) is 5 to 95 parts by mass based on 100 parts by mass of resin solids in the resin composition.
<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 with respect to 100 parts by mass of resin solid content in the resin composition,
The organic group containing a carbon-carbon unsaturated bond includes at least one selected from the group consisting of a vinyl group, an allyl group, an acrylic group, and a methacryl group,
The inorganic filler (B) is an inorganic filler in which the organic group containing the carbon-carbon unsaturated bond is bonded via a silicon atom,
The content of the inorganic filler (B) is 10 to 500 parts by mass with respect to 100 parts by mass of resin solid content in the resin composition,
The inorganic filler (B) is obtained by reacting an organosilicon compound having an organic group containing the carbon-carbon unsaturated bond with silica in a slurry state,
The other thermosetting compound (C) may be a compound represented by formula (M1), a compound represented by formula (M3), or a compound represented by formula (M5). ) and at least one selected from the group consisting of 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 solids in the resin composition.
The resin composition according to <1>.
(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 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 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 represents 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, or an aryl group having 6 to 10 carbon atoms. , represents 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. )
(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 to 10.)
(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 greater than or equal to 1.)
(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 are each independently, Represents a hydrogen atom, an alkyl group, an alkenyl group, or an alkynyl group, 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.)
<18> A prepreg formed from a base material and the resin composition according to any one of <1> to <17>.
<19> A metal foil-clad laminate comprising at least one layer formed from the prepreg according to <18> and metal foil disposed on one or both sides of the layer formed from the prepreg.
<20> A resin composite sheet comprising a support and a layer formed from the resin composition according to any one of <1> to <17> disposed on the surface of the support.
<21> A printed wiring board comprising an insulating layer and a conductor layer disposed on the surface of the insulating layer, wherein the insulating layer is made of the resin composition according to any one of <1> to <17>. A printed wiring board that includes layers formed from materials.
<22> A semiconductor device including the printed wiring board according to <21>.

The present invention has made it possible to provide a novel resin composition with excellent dielectric properties, as well as prepregs, metal foil-clad laminates, resin composite sheets, printed wiring boards, and semiconductor devices.

Hereinafter, a mode for carrying out the present invention (hereinafter simply referred to as "this embodiment") will be described in detail. Note that the present embodiment below is an illustration for explaining the present invention, and the present invention is not limited only to this embodiment.
In addition, in this specification, "~" is used to include the numerical values described before and after it as a lower limit value and an upper limit value.
In this specification, various physical property values and characteristic values are assumed to be at 23° C. unless otherwise stated.
In the description of a group (atomic group) in this specification, the description that does not indicate substituted or unsubstituted includes a group having no substituent (atomic group) as well as a group having a substituent (atomic group). For example, the term "alkyl group" includes not only an alkyl group without a substituent (unsubstituted alkyl group) but also an alkyl group having a substituent (substituted alkyl group). In this specification, for expressions that do not indicate substitution or non-substitution, non-substitution is preferred.
In this specification, the relative dielectric constant refers to the ratio of the dielectric constant to the vacuum dielectric constant of a substance. Further, in this specification, the relative dielectric constant may be simply referred to as "permittivity."
In this specification, "(meth)acrylic" represents both or either acrylic and methacrylic.
If the standards shown in this specification differ in measurement methods etc. depending on the year, unless otherwise stated, the standards as of January 1, 2021 shall be used.

In this specification, the resin solid content refers to the components excluding the inorganic filler (B) and the solvent, and includes the polymer (A) having the structural unit represented by the formula (V) and, if necessary, the component. This is intended to include other thermosetting compounds (C), elastomers, silane coupling agents, and other resin additive components (additives such as flame retardants, etc.). However, the surface treatment agent (silane coupling agent, etc.) bonded to the inorganic filler (B) is included in the inorganic filler (B).

The resin composition of the present embodiment includes 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 the above-mentioned It is characterized by containing a polymer (A) and another thermosetting compound (C) that does not correspond to the inorganic filler (B).
(In formula (V), Ar represents an aromatic hydrocarbon linking group. * represents the bonding position.)
With such a configuration, a resin composition having excellent dielectric properties, particularly low dielectric loss tangent properties, can be obtained. Furthermore, a resin composition having excellent moisture absorption and heat resistance can be obtained.
It is known that inorganic fillers can improve the low thermal expansion properties of resin compositions, but on the other hand, the surface of inorganic fillers usually contains functional groups such as OH groups that deteriorate dielectric properties. Therefore, if used as is, the dielectric properties may not be sufficient. Therefore, one possible method for improving 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 the resin. In this embodiment, an inorganic filler (B) containing an organic group containing a carbon-carbon unsaturated bond is blended into a resin composition containing a polymer (A) having a structural unit represented by formula (V). It has been discovered that by doing so, it is possible to exhibit and maintain better dielectric properties.
On the other hand, a resin composition containing a polymer (A) having a structural unit represented by formula (V) may not necessarily have sufficient dielectric properties and resistance to heat absorption and heat. For example, there may be a case where the equivalent weight of vinyl groups in the polymer (A) having the structural unit represented by formula (V) contained in the resin composition is small. That is, when the equivalent weight of vinyl groups in the polymer (A) having the structural unit represented by formula (V) is small, the number of vinyl groups increases, and unreacted vinyl groups tend to remain when the resin composition is cured. be. It is presumed that such unreacted vinyl groups may deteriorate dielectric properties and moisture absorption heat resistance. Furthermore, as a method of lowering the dielectric properties of a cured product of the resin composition and increasing its resistance to heat absorption and heat, it is possible to blend other components into the resin composition. However, even when other components (especially resin components) are blended, unreacted vinyl groups are often insufficiently reduced, resulting in poor dielectric properties and moisture absorption and heat resistance. It is estimated that there are many.
Under such circumstances, in this embodiment, an inorganic filler containing an organic group containing a carbon-carbon unsaturated bond is added to the resin composition containing the polymer (A) having a structural unit represented by the formula (V). It has been discovered that by blending material (B), more excellent dielectric properties can be exhibited. Furthermore, in this embodiment, by blending the inorganic filler (B) containing an organic group containing a carbon-carbon unsaturated bond, the organic group containing the carbon-carbon unsaturated bond is expressed by the formula (V). It is presumed that by reacting with the vinyl group possessed by the polymer (A) having the structural unit represented by, the proportion of unreacted vinyl groups in the cured product was reduced, and the deterioration of moisture absorption heat resistance was effectively suppressed. Ru.

<Polymer (A) having a structural unit represented by formula (V)>
The resin composition of this embodiment includes a polymer (A) having a structural unit represented by formula (V). By including the polymer (A) having the structural unit represented by formula (V), a resin composition having excellent low dielectric properties (low dielectric constant, low dielectric loss tangent) can be obtained.
(In formula (V), Ar represents an aromatic hydrocarbon linking group. * represents the bonding position.)
The aromatic hydrocarbon linking group may be a group consisting only of aromatic hydrocarbons that may have substituents, or may be a group consisting of aromatic hydrocarbons that may have substituents and other linkages. It may be a group consisting of a combination of groups, and is preferably a group consisting only of an aromatic hydrocarbon which may have a substituent. The substituent that the aromatic hydrocarbon may have is a substituent Z (for example, 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, alkoxy groups having 1 to 6 carbon atoms, hydroxy groups, amino groups, carboxy groups, halogen atoms, etc.). Further, it is preferable that the aromatic hydrocarbon has no substituent.
The aromatic hydrocarbon linking group is usually a divalent linking group.

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, Among these, a phenylene group which may have a substituent is preferred. The above-mentioned substituent Z is exemplified as the substituent, but it is preferable that groups such as the above-mentioned phenylene group have no substituent.

The structural unit represented by formula (V) is the structural unit represented by the following formula (V1), the structural unit represented by the following formula (V2), and the structural unit represented by the following formula (V3). More preferably, at least one is included. Note that * in the following formula represents the bonding position. Further, hereinafter, the constituent units represented by formulas (V1) to (V3) may be collectively referred to as "constituent unit (a)."

In formulas (V1) to (V3), L ¹ is an aromatic hydrocarbon linking group (preferably 6 to 22 carbon atoms, more preferably 6 to 18 carbon atoms, and even more preferably 6 to 10 carbon atoms). Specifically, examples 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. A phenylene group is preferred. The above-mentioned substituent Z is exemplified as the substituent, but it is preferable that groups such as the above-mentioned phenylene group 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, divinylphenanthrene, etc. It will be done. Among them, divinylbenzene is particularly preferred. One type of these divinyl aromatic compounds may be used, or two or more types may be used as necessary.

The polymer (A) having the structural unit represented by formula (V) may be a homopolymer of the structural unit (a) as described above, but it may also be a copolymer with a structural unit derived from another monomer. It may be a combination.
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, and 5 mol % or more. % or more, 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, and 60 mol% or less. % or less, even more preferably 50 mol% or less, even more preferably 40 mol% or less, even more preferably 30 mol% or less, and furthermore, It may be 25 mol% or less, or 20 mol% or less.

As the structural unit derived from other monomers, the structural unit (b) derived from an aromatic compound having one vinyl group (monovinyl aromatic compound) is exemplified.

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

In formula (V4), L ² is an aromatic hydrocarbon linking group, and a preferred example is the above-mentioned example of L ¹ .
R ^V1 is a hydrogen atom or a hydrocarbon group having 1 to 12 carbon atoms (preferably an alkyl group). When R ^V1 is a hydrocarbon group, the number of carbon atoms is preferably 1 to 6, more preferably 1 to 3. R ^V1 and L ² may have the above-mentioned substituent Z.

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

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) shall be 10 mol% or more. is preferable, more preferably 15 mol% or more, furthermore 20 mol% or more, 30 mol% or more, 40 mol% or more, 50 mol% or more, 60 mol% or more, 70 mol% or more, 75 mol%. It may be more than that. The upper limit is preferably 98 mol% or less, more preferably 90 mol% or less, and even more preferably 85 mol% or less.

The polymer (A) having the structural unit represented by formula (V) may have other structural units other than the structural unit (a) and the structural unit (b). Examples of other structural units include a structural unit (c) derived from a cycloolefin compound. Examples of the cycloolefin compound include hydrocarbons having a double bond in the ring structure. Specifically, in addition to monocyclic cyclic olefins such as cyclobutene, cyclopentene, cyclohexene, and cyclooctene, compounds having a norbornene ring structure such as norbornene and dicyclopentadiene, and cycloolefin compounds condensed with aromatic rings such as indene and acenaphthylene. etc. can be mentioned. Examples of norbornene compounds include those described in paragraphs 0037 to 0043 of JP-A-2018-39995, the contents of which are incorporated herein. In addition, the cycloolefin compound illustrated here may further have the above-mentioned substituent Z.

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) shall be 10 mol% or more. is preferable, 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, even more preferably 70 mol% or less, may be 50 mol% or less, and may be 30 mol% or less. It may be the following.

The polymer (A) having a 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, ethylene glycol diacrylate, butadiene, etc. may be mentioned. The copolymerization ratio of the structural unit (d) derived from another polymerizable compound is preferably 30 mol% or less, more preferably 20 mol% or less, and even more preferably 10 mol% or less. .

As one embodiment of the polymer (A) having a structural unit represented by the formula (V), a polymer containing the structural unit (a) as essential and at least one of the structural units (b) to (d) is Illustrated. Furthermore, an embodiment in which the total of structural units (a) to (d) accounts for 95 mol% or more, and further 98 mol% or more of the total structural units is exemplified.
Another embodiment of the polymer (A) having a structural unit represented by formula (V) is a structural unit in which the structural unit (a) is essential and among all the structural units excluding the terminal, a structural unit containing an aromatic ring. is preferably 90 mol% or more, more preferably 95 mol% or more, and may be 100 mol%.
In addition, when calculating the mol% per total structural unit, one structural unit refers to the monomer used to produce the polymer (A) having the structural unit represented by formula (V) (for example, divinyl Aromatic compounds, monovinyl aromatic compounds, etc.) shall originate from one molecule.

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

The structure of the chain end of the polymer (A) having the structural unit represented by the formula (V) is not particularly limited, but when it comes to the group derived from the divinyl aromatic compound, the structure of the following formula (E1) is One example is taking. Note that L ¹ in formula (E1) is the same as defined in formula (V1) above. * represents the bonding position.
*-CH=CH-L ¹ -CH=CH ₂ (E1)

When a group derived from a monovinyl aromatic compound becomes a chain terminal, a structure of the following formula (E2) may be adopted. L ² and R ^V1 in the formula each have the same meaning as defined in the above formula (V4). * represents the bonding position.
*-CH=CH-L ² -R ^V1 (E2)

The molecular weight of the polymer (A) having a structural unit represented by formula (V) is preferably 300 or more, more preferably 500 or more, and 1,000 or more in number average molecular weight Mn. More preferably, it is 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 even more preferably 100,000 or less.
The molecular weight of the polymer (A) having the structural unit represented by formula (V) is preferably 1,000 or more, more preferably 1,500 or more, in weight average molecular weight Mw, 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 above lower limit value or more, the excellent low dielectric properties of the polymer (A) having the structural unit represented by the formula (V), especially the Df and the dielectric properties after moisture absorption, can be improved in the cured product of the resin composition. can be effectively demonstrated. 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 120,000 or less. , 110,000 or less. By setting it below the above-mentioned upper limit, when a prepreg or a resin sheet is laminated on a circuit forming board, embedding failure tends to occur less easily.
The monodispersity (Mw/Mn) expressed by the ratio of weight average molecular weight Mw to number average molecular weight Mn is preferably 100 or less, more preferably 50 or less, and even more preferably 20 or less. . As a lower limit value, it is practical to set it to 1.1 or more, and it may also be 5 or more, 7 or more, and even 10 or more will satisfy the required performance.
The above Mw and Mn are measured according to the description in the examples below.
When the resin composition of the present embodiment contains two or more kinds of polymers (A) having structural units represented by formula (V), it is preferable that Mw, Mn, and Mw/Mn of the mixture satisfy the above ranges.

The equivalent weight of vinyl groups in the polymer (A) having the structural unit represented by formula (V) is 200 g/eq. or more, preferably 230g/eq. More preferably, it is 250 g/eq. More preferably, it is 300g/eq. Above, 350g/eq. It may be more than that. Further, the equivalent weight of the vinyl group is 1200 g/eq. It is preferably less than 1000g/eq. It is more preferable that it is less than 800g/eq. Below, 600g/eq. Below, 500g/eq. Below, 400g/eq. Below, 350g/eq. It may be the following. By setting it to the above lower limit or more, the storage stability of the resin composition tends to improve, and the fluidity of the resin composition tends to improve. Therefore, moldability is improved, voids are less likely to occur during the formation of prepregs, etc., and a more reliable printed wiring board tends to be obtained. On the other hand, by setting it below the above upper limit, the heat resistance of the obtained cured product tends to improve.

Moreover, it is preferable that the cured product of the polymer (A) having the structural unit represented by the formula (V) used in this embodiment has excellent low dielectric properties. For example, the cured product of the polymer (A) having the structural unit represented by the formula (V) used in this embodiment has a dielectric constant (Dk) of 2.80 or less at 10 GHz measured according to the cavity resonator perturbation method. It is preferably 2.60 or less, more preferably 2.50 or less, and even more preferably 2.40 or less. Moreover, the lower limit value of the relative permittivity is practically, for example, 1.80 or more. Further, the cured product of the polymer (A) having the structural unit represented by the formula (V) used in this embodiment has a dielectric loss tangent (Df) of 0.0030 or less at 10 GHz measured according to the cavity resonator perturbation method. It is preferably at most 0.0020, more preferably at most 0.0010. Further, the lower limit value of the dielectric loss tangent is practically, for example, 0.0001 or more.
The dielectric constant (Dk) and the dielectric loss tangent (Df) are measured according to the method described in the Examples below.

In this specification, regarding the polymer (A) having a structural unit represented by formula (V), the 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-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., JP-A-2006-070136 Compounds described in paragraphs 0014 to 0042 of JP-A-2006-089683 and their synthesis reaction conditions, etc., compounds described in paragraphs 0014 to 0061 of JP-A No. 2006-089683 and their synthesis reaction conditions, etc., paragraphs 0008 to 0008 of JP-A-2008-248001. The compounds described in No. 0036, their synthesis reaction conditions, etc. can be referred to and are incorporated herein.

In the resin composition of the present embodiment, the content of the polymer (A) having the structural unit represented by formula (V) is 5 to 70 parts by mass when the resin solid content in the resin composition is 100 parts by mass. Preferably. The lower limit of the content of the polymer (A) having a structural unit represented by formula (V) is preferably 7 parts by mass or more when the resin solid content in the resin composition is 100 parts by mass. It is 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 even more preferably 25 parts by mass. Parts or more are particularly preferred. By setting the content of the polymer (A) having the structural unit represented by formula (V) to the above lower limit or more, low dielectric properties, particularly low dielectric constant, can be effectively achieved. On the other hand, the upper limit of the content of the polymer (A) having a structural unit represented by formula (V) is 65 parts by mass or less when the resin solid content in the resin composition is 100 parts by mass. is preferably 60 parts by mass or less, further 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, and 20 parts by mass or less. or less. By setting it below the above-mentioned 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 may contain two or more types. When two or more types are included, it is preferable that the total amount falls within the above range.

Moreover, the resin composition in this embodiment can also be configured to be substantially free of aromatic divinyl compounds, particularly divinylbenzene. "Substantially free" means that the content of divinylbenzene, and furthermore, the aromatic divinyl compound, is less than 1 part by mass per 100 parts by mass of resin solids in the resin composition, and 0.1 part by mass. It is preferably less than 0.01 part by mass, more preferably less than 0.01 part by mass.

<Inorganic filler (B) containing an organic group containing a carbon-carbon unsaturated bond>
The resin composition of this embodiment includes 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, prepreg, cured product, etc., especially low dielectric loss tangent, flame resistance, and low thermal expansion properties can be further improved. Furthermore, the moisture absorption and heat resistance can also be further improved.

Hereinafter, in the description of the inorganic filler (B) containing an organic group containing a carbon-carbon unsaturated bond, the compound containing an organic group containing a carbon-carbon unsaturated bond will be referred to as a compound (b1), and the inorganic filler A material obtained by removing the organic group containing a carbon-carbon unsaturated bond from (B) may be referred to as an inorganic filler (b2). An example of the compound (b1) is a surface treatment agent for the inorganic filler (b2). Therefore, examples of the inorganic filler (b2) include inorganic fillers treated with a surface treatment agent other than compound (b1) and inorganic fillers not treated with any surface treatment agent.

As mentioned above, the inorganic filler (B) contains an organic group containing a carbon-carbon unsaturated bond.
The organic group containing a carbon-carbon unsaturated bond in this embodiment preferably has a structure of CH ₂ =C(X)- (X is a hydrogen atom or a methyl group), and preferably has a structure such as a vinyl group, an allyl group, or 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.

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, inorganic filler (b2) and carbon-carbon in a slurry containing a compound (b1) containing an organic group containing a carbon-carbon unsaturated bond and inorganic filler (b2). The compound (b1) containing an organic group containing an unsaturated bond can be reacted, 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 are preferably organosilicon compounds containing a carbon-carbon unsaturated bond, such as vinyltrimethoxysilane and vinyltriethoxysilane. Examples include vinylsilane, acrylic silanes such as acryltrimethoxysilane and acrylictriethoxysilane, methacrylsilanes such as methacryltrimethoxysilane and methacryltriethoxysilane, and styrylsilanes such as styryltrimethoxysilane and styryltriethoxysilane. Among these, vinylsilane is more preferred. One type of compound (b1) containing an organic group containing a carbon-carbon unsaturated bond may be used, or two or more types may be used in combination.

The content of the compound (b1) containing an organic group containing a carbon-carbon unsaturated bond bonded to the inorganic filler (b2) in the inorganic filler (B) is based on 100 parts by mass of the inorganic filler (B). On the other hand, the amount 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, and preferably 0.4 parts by mass or more. More preferably, the amount is 0.5 parts by mass or more. When the content is equal to or more than the lower limit, low dielectric properties and low water absorption tend to be further improved. Further, the upper limit of the content of the compound (b1) is preferably 10 parts by mass or less, more preferably 8 parts by mass or less, and 6 parts by mass, based on 100 parts by mass of the inorganic filler (B). It is more preferably at most 5 parts by mass, even more preferably at most 4 parts by mass. By setting it below the above upper limit, heat resistance tends to improve.
When two or more types of compounds (b1) containing an organic group containing a carbon-carbon unsaturated bond are included, the total amount is preferably within the above range.

On the other hand, the inorganic filler (B) includes the inorganic filler (b2) as described above. In such an inorganic filler (b2), the relative permittivity (Dk) measured according to the cavity resonator perturbation method is not limited, but if a low relative permittivity is required, the relative permittivity (Dk) Dk) is preferably lower. In this embodiment, the dielectric constant (Dk) is preferably 8.0 or less, more preferably 6.0 or less, and even more preferably 4.0 or less. Further, the lower limit value of the relative dielectric constant is practically, for example, 2.0 or more. Furthermore, the inorganic filler (b2) used in this embodiment preferably has a dielectric loss tangent (Df) of 0.05 or less, more preferably 0.01 or less, as measured according to the cavity resonator perturbation method. Further, the lower limit value of the dielectric loss tangent is practically, for example, 0.0001 or more.
The type of inorganic filler (b2) used in this embodiment is not particularly limited, and those commonly used in the industry can be suitably used. Specifically, 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. , complex oxides such as zinc borate, zinc stannate, forsterite, barium titanate, strontium titanate, calcium titanate, nitrides such as boron nitride, agglomerated boron nitride, silicon nitride, aluminum nitride, aluminum hydroxide, Heat-treated aluminum hydroxide products (aluminum hydroxide heat-treated to reduce some of the crystal water), metal hydroxides (including hydrates) such as boehmite and magnesium hydroxide, molybdenum oxide and molybdic acid Molybdenum compounds such as zinc, barium sulfate, clay, kaolin, talc, calcined clay, calcined kaolin, calcined talc, mica, E-glass, A-glass, NE-glass, C-glass, L-glass, D-glass, Examples include 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 selected from the group consisting of silica, aluminum hydroxide, aluminum nitride, boron nitride, forsterite, titanium oxide, barium titanate, strontium titanate, and calcium titanate. If a low dielectric constant is required, it is more preferably one or more selected from the group consisting of silica and aluminum hydroxide, and it is silica. is even more preferable.

In the present embodiment, the inorganic filler (B) is obtained, for example, by bonding a compound (b1) containing an organic group containing a carbon-carbon unsaturated bond to the surface of the 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 is reacted with the inorganic filler (b2) in the liquid phase slurry, a portion of the compound (b1) is integrated. In some cases, the compound may be present in the slurry as a free compound.
Specifically, as described above, in a slurry state, a compound (b1) containing an organic group containing a carbon-carbon unsaturated bond (preferably an organosilicon compound) and an inorganic filler (b2) (preferably a silica ) is preferably reacted. At this time, the number of functional groups on the surface of the inorganic filler (b2) (functional groups that react with the compound (b1), preferably hydroxyl groups) is higher than that of the compound (b1) containing an organic group containing a carbon-carbon unsaturated bond. It is preferable that the number of functional groups therein (the total number of functional groups that react with the functional groups on the surface of the inorganic filler (b2), preferably hydroxyl groups and alkoxy groups) is larger. Specifically, the number of functional groups in the compound (b1) is preferably 1 to 5 times the number of functional groups in the inorganic filler (b2), more preferably more than 1 times and 5 times or less. By reacting the compound (b1) having an excessive number of functional groups with the inorganic filler (b2) in this manner, the effects of the present invention tend to be exhibited more effectively.

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

The resin composition of the present embodiment may include an inorganic filler (B) and a compound (b1) containing an organic group containing a carbon-carbon unsaturated bond that is not bonded to the inorganic filler (B). preferable. Due to the presence of the compound (b1) that is not bonded to the inorganic filler (B), the vinyl groups of the polymer (A) are more effectively capped, and the effects of the present invention are more effectively exhibited. It is assumed that
For these reasons, in the present embodiment, the inorganic filler (b1) produced using the compound (b1) in an amount such that the functional group equivalent on the surface of the inorganic filler (b2) is in excess of the functional group equivalent on the surface of the inorganic filler (b2) is used in the present embodiment. It is preferable to use B) in its slurry state without separating it from the slurry to produce a resin composition.

When the resin composition of the present embodiment includes an inorganic filler (B) and a compound (b1) containing an organic group containing a carbon-carbon unsaturated bond that is 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, and 1 part by mass or less based on 100 parts by mass of the inorganic filler (B). It is more preferably 0.5 parts by mass or less, even more preferably 0.2 parts by mass or less. By setting it below the above-mentioned upper limit, insulation reliability tends to improve and low dielectric constant properties tend to improve. The lower limit may be 0 parts by mass or more, but preferably 0.0001 parts by mass or more.
The resin composition of the present embodiment may contain only one type of 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 types of compound (b1) containing an organic group containing a carbon-carbon unsaturated bond. It may contain more than one species. When two or more types are included, it is preferable that the total amount falls within the above range.

The content of the inorganic filler (B) in the resin composition of the present embodiment is preferably 10 parts by mass or more, more preferably 20 parts by mass or more, and 40 parts by mass or more, based on 100 parts by mass of the resin solid content. It is more preferably at least 60 parts by mass, even more preferably at least 80 parts by mass. By setting it to the above lower limit or more, the heat resistance and low thermal expansion properties of the obtained resin composition, prepreg, cured product, etc. tend to be further improved. Further, 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, and 300 parts by mass based on 100 parts by mass of the resin solid content. It is more preferably at most 200 parts by mass, even more preferably at most 150 parts by mass. By setting it below the upper limit, the moldability of prepregs and the like and the lamination moldability of laminates and the like tend to be further improved.
In the resin composition of the present embodiment, as an example of a preferred embodiment, 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 this embodiment may contain only one type of inorganic filler (B), or may contain two or more types of inorganic filler (B). When two or more types are included, it is preferable that the total amount falls within the above range.

<Other thermosetting compounds (C)>
It is preferable that the resin composition of this embodiment further contains another thermosetting compound (C) that does not correspond to the polymer (A) and the inorganic filler (B). By including such components, other desired performances required of 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 still more preferably 300 or more. Further, 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. Further, the equivalent weight of the functional group of the other thermosetting compound (C) is preferably 100 g/eq. Above, more preferably 150g/eq. Above, more preferably 200g/eq. That's all. Further, the upper limit of the equivalent weight of the functional group of the other thermosetting compound (C) is preferably 1,500 g/eq. Below, more preferably 1,300g/eq. It is as follows.
In this embodiment, it is particularly preferable that the other thermosetting compound (C) satisfies the above-mentioned weight average molecular weight and functional group equivalent. Such other thermosetting compounds (C) tend to have a lower weight average molecular weight and higher functional group concentration than the polymer (A) having the structural unit represented by formula (V). Therefore, the number of crosslinking points increases, and the moisture absorption and heat resistance of the resulting cured product can be improved more effectively.
In this embodiment, 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 are used. The compound represented by formula (M1) preferably contains at least one selected from the group, more preferably contains a maleimide compound and/or a polyphenylene ether compound containing two or more carbon-carbon unsaturated double bonds. M1), a compound represented by formula (M3), a compound represented by formula (M5), and a compound represented by formula (OP-1). Preferably, it 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). is more preferable.
(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 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 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 represents 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, or an aryl group having 6 to 10 carbon atoms. , represents 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. )
(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 to 10.)
(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 greater than or equal to 1.)
(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 are 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.)

<<Maleimide compound>>
The resin composition of this embodiment may contain a maleimide compound. The resin composition of this embodiment has one or more (preferably 2 to 12, more preferably 2 to 6, still more preferably 2 to 4, even more preferably 2 or 3, even more preferably 2) per molecule. The compound is not particularly limited as long as it has a maleimide group, 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, and compounds represented by formula (M1) and/or formula ( The compound represented by M3) is more preferred, and the compound (M1) represented by formula (M1) is even more preferred. When these maleimide compounds are used in materials for printed wiring boards (for example, metal foil-clad laminates), they can provide excellent heat resistance. In particular, when the compound (M1) represented by formula (M1) is used, low dielectric properties tend to be achieved more effectively.
(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 n ₁ represents an integer greater than or equal to 1.)
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, it is a methyl group, and even more preferably a hydrogen atom.
R ⁵² is preferably a methyl group.
n ₁ 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, even more preferably 1 or 2, and even more preferably 1.
The compound represented by formula (M0) may be one type or a mixture of two or more types. Examples of mixtures include mixtures of compounds in which _n1 is different, mixtures of compounds in which the types of substituents for ^R51 and/or ^R52 are different, and the bonding position of the maleimide group and the oxygen atom to the benzene ring (meta position, para position, Examples include mixtures of compounds having different positions (ortho positions), and mixtures of compounds having two or more of the above-mentioned different points combined. The same applies to the compounds represented by formulas (M1) to (M5) below.
(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 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 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 represents 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, or an aryl group having 6 to 10 carbon atoms. , represents 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. )

R ^M1 , R ^M2 , R ^M3 , and R ^M4 in the formula each independently represent 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 a methyl group, an ethyl group, a propyl group, or a butyl group. More preferred is a methyl group, especially a methyl group. R ^M1 and R ^M3 are each independently preferably an alkyl group, and R ^M2 and R ^M4 are preferably a hydrogen atom.
R ^M5 and R ^M6 each independently represent 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, and still more preferably a methyl group, an ethyl group, a propyl group, or a butyl group, with a methyl group being particularly preferred. preferable.
Ar ^M represents a divalent aromatic group, preferably a phenylene group, a naphthalenediyl group, a phenanthrenediyl group, an anthracenediyl group, more preferably a phenylene group, still more preferably a m-phenylene group. Ar ^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, a methyl group, Ethyl group, propyl group, and butyl group are more preferable, and methyl group is particularly preferable. However, it is preferable that Ar ^M is 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). R ^M7 and R ^M8 each independently represent 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, preferably 2.
lx is 0 or 1, preferably 1.
R ^M9 and R ^M10 each independently represent a hydrogen atom or an alkyl group, and an alkyl group is more preferred. 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, and still more preferably a methyl group, an ethyl group, a propyl group, or a butyl group, with a methyl group being particularly preferred. preferable.
R ^M11 , R ^M12 , R ^M13 , and R ^M14 each independently represent 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 a methyl group, an ethyl group, a propyl group, or a butyl group. More preferred is a methyl group, especially a methyl group. R ^M12 and R ^M13 are each independently preferably an alkyl group, and R ^M11 and R ^M14 are 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, or an aryl group having 1 to 10 carbon atoms. represents an aryloxy group, an arylthio group having 1 to 10 carbon atoms, a halogen atom, a hydroxyl group, or a mercapto group, an alkyl group having 1 to 4 carbon atoms, a cycloalkyl group having 3 to 6 carbon atoms, or a cycloalkyl group having 6 to 10 carbon atoms. is preferably an aryl group.
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 from 1 to 20. nx may be an integer of 10 or less.
The resin composition of the present embodiment may contain only one type of compound (M1) represented by formula (M1), or may contain two or more types of compounds having at least different values of nx. You can stay there. When two or more types are included, the average value of nx (average number of repeating units) n in the compound (M1) represented by formula (M1) in the resin composition has a low melting point (low softening point) and a melt viscosity. In order to have a low value and excellent handling properties, it is preferably 0.92 or more, more preferably 0.95 or more, even more preferably 1.0 or more, and 1.1 or more. It is more preferable that there be. Further, 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 5. It may be 0 or less. The same applies to equation (M1-1) etc. which will be described later.

The compound (M1) represented by formula (M1) is preferably a compound represented by formula (M1-1) below.
(In formula (M1-1), R ^M21 , R ^M22 , R ^M23 , and R ^M24 each independently represent a hydrogen atom or an organic group. R ^M25 and R ^M26 each independently represent a hydrogen atom or an alkyl R ^M27 , R ^M28 , R ^M29 , and R ^M30 each independently represent a hydrogen atom or an organic group. R ^M31 and R ^M32 each independently represent a hydrogen atom or an alkyl group. R ^M33 , R ^M34 , R ^M35 , and R ^M36 each independently represent a hydrogen atom or an organic group. R ^M37 , R ^M38 , and R ^M39 each independently represent a hydrogen atom or an alkyl group. nx is Represents an integer between 1 and 20.)

R ^M21 , R ^M22 , R ^M23 , and R ^M24 in the formula each independently represent 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 a methyl group, an ethyl group, a propyl group, or a butyl group. More preferred is a methyl group. R ^M21 and R ^M23 are preferably alkyl groups, and R ^M22 and R ^M24 are preferably hydrogen atoms.
R ^M25 and R ^M26 each independently represent 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, and still more preferably a methyl group, an ethyl group, a propyl group, or a butyl group, with a methyl group being particularly preferred. preferable.
R ^M27 , R ^M28 , R ^M29 , and R ^M30 each independently represent a hydrogen atom or an organic group, and 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, and a methyl group, an ethyl group, a propyl group, or a butyl group. More preferred is a methyl group.
R ^M31 and R ^M32 each independently represent 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, and still more preferably a methyl group, an ethyl group, a propyl group, or a butyl group, with a methyl group being particularly preferred. preferable.
R ^M33 , R ^M34 , R ^M35 , and R ^M36 each independently represent 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 a methyl group, an ethyl group, a propyl group, or a butyl group. More preferred is a methyl group.
R ^M33 and R ^M36 are preferably hydrogen atoms, and R ^M34 and R ^M35 are preferably alkyl groups.
R ^M37 , R ^M38 , and R ^M39 each independently represent a hydrogen atom or an alkyl group, and an alkyl group is preferable. 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, and still more preferably a methyl group, an ethyl group, a propyl group, or a butyl group, with a methyl group being particularly preferred. preferable.
nx represents an integer from 1 to 20. nx may be an integer of 10 or less.

The compound represented by formula (M1-1) is preferably a compound represented by formula (M1-2) below.
(In formula (M1-2), R ^M21 , R ^M22 , R ^M23 , and R ^M24 each independently represent a hydrogen atom or an organic group. R ^M25 and R ^M26 each independently represent a hydrogen atom or an alkyl R ^M27 , R ^M28 , R ^M29 , and R ^M30 each independently represent a hydrogen atom or an organic group. R ^M31 and R ^M32 each independently represent a hydrogen atom or an alkyl group. R ^M33 , R ^M34 , R ^M35 , and R ^M36 each independently represent a hydrogen atom or an organic group. R ^M37 , R ^M38 , and R ^M39 each independently represent a hydrogen atom or an alkyl group. nx is Represents an integer between 1 and 20.)

In formula (M1-2), ^RM21 , ^RM22 , ^RM23 , ^RM24 , ^RM25 , RM26, ^RM27 , ^RM28 , ^RM29 , ^{RM30 , RM31} , ^RM32 , ^RM33 , ^RM34 , R ^M35 , R ^M36 , R ^M37 , R ^M38 , R ^M39 , and nx are R ^M21 , R ^M22 , R ^M23 , R ^M24 , R ^M25 , R ^M26 , R ^M27 in formula (M1-1), respectively; It is synonymous with 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. .

The compound represented by the formula (M1-1) is further preferably a compound represented by the following formula (M1-3), and more preferably a compound represented by the following formula (M1-4). More preferred.
(In formula (M1-3), nx represents an integer from 1 to 20.)
nx may be an integer of 10 or less.
(In formula (M1-4), nx represents an integer from 1 to 20.)

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. When the amount is equal to or more than the lower limit, the resulting cured product tends to have improved low dielectric properties and low water absorption. Further, 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, and preferably 5,000 or less. More preferably, it is 4000 or less. By setting it below the above-mentioned upper limit, the heat resistance and handleability of the obtained cured product tend to be further improved.
(In formula (M2), R ⁵⁴ each independently represents a hydrogen atom or a methyl group, and n ₄ represents an integer of 1 or more.)
n ₄ 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.
(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 to 10.)
R ⁵⁵ is preferably a hydrogen atom, methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, isobutyl group, t-butyl group, n-pentyl group, or phenyl group; More preferably, it is a methyl group, and even more preferably a hydrogen atom.
n ₅ 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.
(In formula (M4), R ⁵⁶ each independently represents a hydrogen atom, a methyl group, or an ethyl group, and R ⁵⁷ each independently represents a hydrogen atom or a methyl group.)

(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 greater than or equal to 1.)
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; One of the methyl groups is more preferable, and a hydrogen atom is even more preferable.
R ⁵⁹ is preferably a methyl group.
n ₆ 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, even more preferably 1 or 2, and may be 1.
The compound represented by formula (M5) may be a mixture of compounds having different n ₆ values, and is preferably a mixture. Further, as described in the section of the compound represented by formula (M0), it may be a mixture of compounds having different parts.

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

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'-diphenyl ether bismaleimide, 4,4'-diphenylsulfone bismaleimide, 1,3 Examples include -bis(3-maleimidophenoxy)benzene, 1,3-bis(4-maleimidophenoxy)benzene, prepolymers thereof, and prepolymers of these maleimides and amines.

When the resin composition of this embodiment contains a maleimide compound, the lower limit of the content of the maleimide compound is preferably 1 part by mass or more, and 5 parts by mass, based on 100 parts by mass of resin solids in the resin composition. It is more preferably at least 10 parts by mass, even more preferably at least 20 parts by mass, even more preferably at least 25 parts by mass. When the content of the maleimide compound is 1 part by mass or more, the flame resistance of the obtained cured product tends to improve. Further, the upper limit of the content of the maleimide compound is preferably 70 parts by mass or less, more preferably 50 parts by mass or less, and 40 parts by mass based on 100 parts by mass of the resin solid content in the resin composition. The following may be sufficient. When the content of the maleimide compound is 70 parts by mass or less, the metal foil peel strength and low water absorption tend to improve.
The resin composition in this embodiment may contain only one type of maleimide compound, or may contain two or more types of maleimide compounds. When two or more types are included, it is preferable that the total amount falls within the above range.
Moreover, the resin composition in this embodiment can also be configured to substantially not contain a maleimide compound, particularly a monofunctional maleimide compound. "Substantially free" means that the content of the monofunctional maleimide compound, and furthermore, the maleimide compound, is less than 1 part by mass with respect to 100 parts by mass of resin solid content in the resin composition, and 0.1 mass part. It is preferably less than 0.01 part by mass, more preferably less than 0.01 part by mass. By substantially not containing monofunctional maleimide, the relationship between the maleimide group of the maleimide compound and the vinyl group of the polymer (A) having the structural unit represented by formula (V) or the inorganic filler (B) is reduced. The reaction between the vinyl groups proceeds preferentially over the reaction between the vinyl groups, and a cured product with lower dielectric properties tends to be obtained. Further, when the reaction between vinyl groups proceeds preferentially, the degree of curing after heating tends to improve from the viewpoint of steric hindrance.

<<Polyphenylene ether compound containing two or more carbon-carbon unsaturated double bonds>>
The resin composition of this 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 must be a polyphenylene ether compound having two or more groups selected from the group consisting of (meth)acrylic group, maleimide group, and vinylbenzyl group at the end. is preferred. By using these polyphenylene ether compounds, there is a tendency that the dielectric properties, low water absorption, etc. of printed wiring boards and the like can be more effectively improved.
These details will be explained below.

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).

(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. )

The polyphenylene ether compound containing two or more carbon-carbon unsaturated double bonds has the formula (X2):
(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 or a phenyl group having 6 or less carbon atoms. R 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.)
A repeating unit represented by and/or formula (X3):
(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, hydrogen atom, alkyl 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.

A polyphenylene ether compound containing two or more carbon-carbon unsaturated double bonds is a modified polyphenylene ether compound (hereinafter referred to as a "modified polyphenylene ether compound (g )" is preferable, and a modified 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 the terminal is more preferable. . By employing such a modified polyphenylene ether compound (g), it becomes possible to further reduce the dielectric loss tangent (Df) of the cured product of the resin composition, and to increase low water absorption and metal foil peel strength. . These may be used alone or in combination of two or more.

Examples of the modified polyphenylene ether compound (g) include a compound represented by formula (OP-1).
(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 are 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.)
When n ₂ is an integer of 2 or more, and for n ₃ , the n ₂ structural units (YO) and/or the n ₃ structural units may be the same or different. n ₃ is preferably 2.

The modified polyphenylene ether compound (g) in this embodiment is preferably a compound represented by formula (OP-2).
Here, -(O-X-O)- is the formula (OP-3):
(In formula (OP-3), R ⁴ , R ⁵ , R ⁶ , R ¹⁰ , and R ¹¹ may be the same or different and are an alkyl group or a phenyl group having 6 or less carbon atoms. R 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):
(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 each has a hydrogen atom and a carbon number of 6 or less. is an alkyl group or phenyl group. -A- is a linear, branched or cyclic divalent hydrocarbon group having 20 or less carbon atoms.

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

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

In the modified polyphenylene ether compound (g), R ⁴ , R ⁵ , R ⁶ , R ¹⁰ , R ¹¹ , R ²⁰ and R ²¹ are alkyl groups 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 ²³ are hydrogen atoms or alkyl groups having 3 or less carbon atoms, polyphenylene ether Compounds are preferred, and in particular -(O-X-O)- represented by formula (OP-3) or formula (OP-4) is represented by formula (OP-9), formula (OP-10), and/or Formula (OP-11) and -(YO)- represented by formula (OP-5) are preferably formula (OP-12) or formula (OP-13). When a and/or b are integers of 2 or more, -(Y-O)- of 2 or more each independently represents a structure in which two or more of formula (OP-12) and/or formula (OP-13) are arranged. Alternatively, it may have a structure in which formula (OP-12) and formula (OP-13) are arranged in blocks or randomly.

(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 straight line having 20 or less carbon atoms. It is a chain, branched, or cyclic divalent hydrocarbon group.)
Specific examples of -B- include the same examples as -A- in formula (OP-4).
(In formula (OP-11), -B- is a straight chain, branched or cyclic divalent hydrocarbon group having 20 or less carbon atoms.)
Specific examples of -B- include the same examples as -A- in formula (OP-4).

In addition, for details of the polyphenylene ether compound containing two or more carbon-carbon unsaturated double bonds, the description in JP 2018-016709 can be referred to, and the contents thereof are incorporated herein.

The number average molecular weight of a polyphenylene ether compound (preferably a modified polyphenylene ether compound (g)) containing two or more carbon-carbon unsaturated double bonds (preferably a modified polyphenylene ether compound (g)) in terms of polystyrene determined by GPC (gel permeation chromatography) is 500 or more and 3,000 or more. It is preferable that it is below. When the number average molecular weight is 500 or more, stickiness tends to be further suppressed when the resin composition of this embodiment is formed into a coating film. When the number average molecular weight is 3,000 or less, the solubility in a solvent tends to be further improved.
In addition, the weight average molecular weight of the polyphenylene ether compound (preferably the modified polyphenylene ether compound (g)) containing two or more carbon-carbon unsaturated double bonds (preferably the modified polyphenylene ether compound (g)) in terms of polystyrene by GPC is 800 or more and 10,000 or less. It is preferably 800 or more and 5,000 or less. By setting the above lower limit or more, the dielectric constant (Dk) and dielectric loss tangent (Df) of the cured product of the resin composition tend to become lower. By setting the above upper limit or less, the varnish etc. described below The solubility, low viscosity, and moldability of the resin composition in the solvent during production tend to be further improved.
Further, 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, and 400 to 2500 g. It is more preferable that By setting it above the lower limit, the relative dielectric constant (Dk) and dielectric loss tangent (Df) of the cured product of the resin composition tend to become lower. By setting it below the above upper limit, the solubility, low viscosity, and moldability of the resin composition in a solvent tend to be further improved.

When the resin composition of the present 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, and 7 parts by mass, based on 100 parts by mass of resin solid content in the resin composition. It is more preferable that the amount is above, and even more preferably that it is 10 parts by mass or more. When the amount is equal to or more than the lower limit, the resulting cured product tends to have improved low water absorption and low dielectric properties (Dk and/or Df). Further, 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, and 60 parts by mass or less, based on 100 parts by mass of the resin solid content in the resin composition. It is more preferably at most 50 parts by mass, even more preferably at most 40 parts by mass, even more preferably at most 35 parts by mass, and even more preferably at most 25 parts by mass. Even more preferably, the amount may be 20 parts by mass or less. When the amount is below the upper limit, the heat resistance and chemical resistance of the resulting cured product tend to be further improved.
The resin composition in this embodiment may contain only one type of polyphenylene ether compound containing two or more carbon-carbon unsaturated double bonds, or may contain two or more types. When two or more types are included, it is preferable that the total amount falls within the above range.

<<Cyanate ester compound>>
The resin composition of this embodiment may contain a cyanate ester compound.
The cyanate ester compound has one or more cyanate groups (cyanato groups) in one molecule (preferably 2 to 12, more preferably 2 to 6, still more preferably 2 to 4, even more preferably 2 or 3, even more preferably is not particularly limited as long as it is a compound containing 2), and a wide range of compounds commonly used in the field of printed wiring boards can be used. Further, the cyanate ester compound is preferably a compound in which a cyanate group is directly bonded to an aromatic skeleton (aromatic ring).
Examples of cyanate ester compounds include phenol novolac type cyanate ester compounds, naphthol aralkyl type cyanate ester compounds (naphthol aralkyl type cyanate), naphthylene ether type cyanate ester compounds, biphenylaralkyl type cyanate ester compounds, and xylene resins. Consists of type cyanate ester compound, trisphenolmethane type cyanate ester compound, adamantane skeleton type cyanate ester compound, bisphenol M type cyanate ester compound, bisphenol A type cyanate ester compound, and diallylbisphenol A type cyanate ester compound At least one selected from the group. Among these, from the viewpoint of further improving the low water absorption of the obtained cured product, phenol novolak type cyanate ester compounds, naphthol aralkyl type cyanate ester compounds, naphthylene ether type cyanate ester compounds, xylene resin type cyanate ester compounds are used. It is preferably at least one selected from the group consisting of ester compounds, bisphenol M-type cyanate ester compounds, bisphenol A-type cyanate ester compounds, and diallylbisphenol A-type cyanate ester compounds, and phenol novolak-type cyanate esters. The cyanate compound is more preferably at least one selected from the group consisting of a naphthol aralkyl cyanate ester compound, and a naphthol aralkyl cyanate ester compound. 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 number of functional group equivalents, and the number of unreacted cyanate ester groups is small. Therefore, cured products of resin compositions using these materials tend to have even better low water absorption. Moreover, mainly due to having an aromatic skeleton or an adamantane skeleton, plating adhesion tends to be further improved.

As the naphthol aralkyl cyanate ester compound, a compound represented by formula (1) is more preferable.

(In formula (1), ^R3 each independently represents a hydrogen atom or a methyl group, and n3 represents an integer of 1 or more.)

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, even more preferably an integer of 1 to 6.

Further, the novolac type cyanate ester compound is not particularly limited, but for example, a compound represented by the following formula (VII) is preferable.
(In formula (VII), R ⁶ each independently represents a hydrogen atom or a methyl group, and n 7 represents an integer of 1 or more.)

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.

The bisphenol A type cyanate ester compound is one selected from the group consisting of 2,2-bis(4-cyanatophenyl)propane and a prepolymer of 2,2-bis(4-cyanatophenyl)propane. The above may also be used.

The resin composition of the present embodiment preferably contains a cyanate ester compound within a range that does not impair the effects of the present invention. When the resin composition of the present embodiment contains a cyanate ester compound, the lower limit of its content is preferably 0.1 parts by mass or more based on 100 parts by mass of resin solids in the resin composition. , more preferably 2 parts by mass or more, and still more preferably 4 parts by mass or more. When the content of the cyanate ester compound is 0.1 parts by mass or more, the heat resistance, flame resistance, chemical resistance, low dielectric constant, low dielectric loss tangent, and insulation properties of the obtained cured product are improved. There is a tendency. When the resin composition of this embodiment contains a cyanate ester compound, the upper limit of the content of the cyanate ester compound may be 70 parts by mass or less based on 100 parts by mass of the resin solid content in the resin composition. Preferably, the amount is 50 parts by mass or less, 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 10 parts by mass. Below, the amount may be 5 parts by mass or less.
The resin composition in this embodiment may contain only one type of cyanate ester compound, or may contain two or more types of cyanate ester compounds. When two or more types are included, it is preferable that the total amount falls within the above range.

<<Epoxy compound>>
The resin composition of this embodiment may contain an epoxy compound.
An epoxy compound is a compound having one or more (preferably 2 to 12, more preferably 2 to 6, still more preferably 2 to 4, even more preferably 2 or 3, even more preferably 2) epoxy groups in one molecule. Alternatively, it is not particularly limited as long as it is a resin, and a wide variety of compounds commonly used in the field of printed wiring boards can be used.
Examples of epoxy compounds include bisphenol A epoxy resin, bisphenol E epoxy resin, bisphenol F epoxy resin, bisphenol S epoxy resin, phenol novolac epoxy resin, bisphenol A novolac epoxy resin, glycidyl ester epoxy resin, and aralkyl epoxy resin. Novolac type epoxy resin, biphenylaralkyl type epoxy resin, naphthylene ether type epoxy resin, cresol novolac type epoxy resin, multifunctional phenol type epoxy resin, naphthalene type epoxy resin, anthracene type epoxy resin, naphthalene skeleton modified novolac type epoxy resin, phenol Aralkyl type epoxy resin, naphthol aralkyl type epoxy resin, dicyclopentadiene type epoxy resin, biphenyl type epoxy resin, alicyclic epoxy resin, polyol type epoxy resin, phosphorus-containing epoxy resin, glycidyl amine, glycidyl ester, butadiene, etc. Examples include compounds in which bonds are epoxidized and compounds obtained by reacting hydroxyl group-containing silicone resins with epichlorohydrin. By using these, the moldability and adhesion of the resin composition are improved. Among these, from the viewpoint of further improving flame retardancy and heat resistance, biphenylaralkyl epoxy resins, naphthylene ether epoxy resins, polyfunctional phenol epoxy resins, and naphthalene epoxy resins are preferred; More preferably, it is a type epoxy resin.

The resin composition of the present embodiment preferably contains an epoxy compound within a range that does not impair the effects of the present invention. When the resin composition of the present embodiment contains an epoxy compound, the content thereof is preferably 0.1 parts by mass or more, and 1 part by mass or more, based on 100 parts by mass of resin solids in the resin composition. It is more preferable that the amount is at least 2 parts by mass, and even more preferably 2 parts by mass or more. When the content of the epoxy compound is 0.1 part by mass or more, the peel strength and toughness of the metal foil tend to improve. When the resin composition of this embodiment contains an epoxy compound, the upper limit of the content of the epoxy compound is preferably 50 parts by mass or less, and 30 parts by mass or less, based on 100 parts by mass of the resin solid content in the resin composition. It is more preferably at most 20 parts by mass, even more preferably at most 10 parts by mass, even more preferably at most 8 parts by mass, and even more preferably at most 5 parts by mass. is even more preferred. When the content of the epoxy compound is 50 parts by mass or less, the electrical properties of the obtained cured product tend to improve.
The resin composition in this embodiment may contain only one type of epoxy compound, or may contain two or more types of epoxy compounds. When two or more types are included, it is preferable that the total amount falls within the above range.
Moreover, the resin composition in this embodiment can also have a structure that does not substantially contain an epoxy compound. "Substantially free" means that the content of the epoxy compound is less than 0.1 parts by mass, preferably less than 0.01 parts by mass, based on 100 parts by mass of resin solids in the resin composition. , and even less than 0.001 part by mass.

<<Phenol compounds>>
The resin composition of this embodiment may contain a phenol compound.
The phenol compound has one or more (preferably 2 to 12, more preferably 2 to 6, still more preferably 2 to 4, even more preferably 2 or 3, even more preferably 2) phenolic hydroxyl groups in one molecule. The phenol compound is not particularly limited, and a wide variety of compounds commonly used in the field of printed wiring boards can be used.
Examples of the phenol compound include bisphenol A type phenol resin, bisphenol E type phenol resin, bisphenol F type phenol resin, bisphenol S type phenol resin, phenol novolak resin, bisphenol A novolac type phenol resin, glycidyl ester type phenol resin, aralkyl novolak phenol. Resin, biphenylaralkyl type phenolic resin, cresol novolac type phenolic resin, polyfunctional phenolic resin, naphthol resin, naphthol novolak resin, polyfunctional naphthol resin, anthracene type phenolic resin, naphthalene skeleton modified novolak type phenolic resin, phenol aralkyl type phenolic resin, Examples include 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 obtained cured product, at least one selected from the group consisting of biphenyl aralkyl type phenol resin, naphthol aralkyl type phenol resin, phosphorus-containing phenol resin, and hydroxyl group-containing silicone resin. Preferably it is a seed.

The resin composition of the present embodiment preferably contains a phenol compound within a range that does not impair the effects of the present invention. When the resin composition of the present embodiment contains a phenol compound, the content thereof is preferably 0.1 parts by mass or more, and 50 parts by mass based on 100 parts by mass of resin solids in the resin composition. It is preferable that it is below.
The resin composition in this embodiment may contain only one type of phenol compound, or may contain two or more types of phenol compounds. When two or more types are included, it is preferable that the total amount falls within the above range.
Moreover, the resin composition in this embodiment can also have a structure that does not substantially contain a phenol compound. "Substantially free" means that the content of the phenol compound is less than 0.1 parts by mass based on 100 parts by mass of resin solids in the resin composition.

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

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

In addition, commercially available alkenyl-substituted nadimide compounds can also be used. Commercially available products include, but are not limited to, BANI-M (manufactured by Maruzen Petrochemical Co., Ltd., a compound represented by formula (AN-4)), BANI-X (manufactured by Maruzen Petrochemical Co., Ltd.) and the compound represented by the formula (AN-5).

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 is preferably 0.1 parts by mass or more, and 50 parts by mass or more, based on 100 parts by mass of resin solids in the resin composition. It is preferably less than parts by mass.
The resin composition in this embodiment may contain only one type of alkenyl-substituted nadimide compound, or may contain two or more types of alkenyl-substituted nadimide compounds. When two or more types are included, it is preferable that the total amount falls within the above range.
Moreover, the resin composition in this embodiment can also be configured to be substantially free of alkenyl-substituted nadimide compounds. "Substantially free" means that the content of the alkenyl-substituted nadimide compound is less than 0.1 part by mass based on 100 parts by mass of resin solid content in the resin composition.

<<Oxetane resin>>
The resin composition of this embodiment may contain oxetane resin.
The oxetane resin is particularly 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, even more preferably 2). There are no limitations, and a wide variety of compounds commonly used in the field of printed wiring boards can be used.
Examples of the oxetane resin include oxetane, alkyloxetane (for example, 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.), OXT-121 (manufactured by Toagosei Co., Ltd.) ), etc.

The resin composition of this embodiment preferably contains an oxetane resin within a range that does not impair the effects of the present invention. When the resin composition of the present embodiment contains an oxetane resin, the content thereof is preferably 0.1 parts by mass or more, and 1 part by mass or more based on 100 parts by mass of resin solids in the resin composition. More preferably, the amount is 2 parts by mass or more. When the content of the oxetane resin is 0.1 parts by mass or more, the peel strength and toughness of the metal foil tend to improve. When the resin composition of this embodiment contains an oxetane resin, the upper limit of the content of oxetane resin is preferably 50 parts by mass or less, and 30 parts by mass or less, based on 100 parts by mass of resin solid content in the resin composition. It is more preferably at most 20 parts by mass, even more preferably at most 10 parts by mass, even more preferably at most 8 parts by mass. When the content of the oxetane resin is 50 parts by mass or less, the electrical properties of the resulting cured product tend to improve.
The resin composition in this embodiment may contain only one type of oxetane resin, or may contain two or more types of oxetane resin. When two or more types are included, it is preferable that the total amount falls within the above range.
Moreover, the resin composition in this embodiment can also be configured to substantially not contain oxetane resin. "Substantially free" means that the content of oxetane resin is less than 0.1 part by mass based on 100 parts by mass of resin solid content in the resin composition.

<<Benzoxazine compound>>
The resin composition of this embodiment may contain a benzoxazine compound.
The benzoxazine compound includes 2 or more (preferably 2 to 12, more preferably 2 to 6, even more preferably 2 to 4, even more preferably 2 or 3, even more preferably 2) dihydrobenzoxazines in one molecule. Any compound having a ring is not particularly limited, 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.). ), etc.

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 based on 100 parts by mass of resin solids in the resin composition. It is preferable that
The resin composition in this embodiment may contain only one type of benzoxazine compound, or may contain two or more types of benzoxazine compounds. When two or more types are included, it is preferable that the total amount falls within the above range.
Moreover, the resin composition in this embodiment can also be configured to substantially not contain a benzoxazine compound. "Substantially free" means that the content of the benzoxazine compound is less than 0.1 part by mass based on 100 parts by mass of resin solid content in the resin composition.

The content (total amount) of the thermosetting compound (C) in the resin composition of the present embodiment is preferably 5 parts by mass or more, and preferably 10 parts by mass or more based on 100 parts by mass of the resin solid content. It is 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. By setting it above the lower limit, heat resistance, plating adhesion, low thermal expansion, etc. tend to be further improved. Further, the upper limit value of the content of the thermosetting compound (C) is preferably 95 parts by mass or less, more preferably 85 parts by mass or less, and 75 parts by mass, based on 100 parts by mass of the resin solid content. It is more preferably at most 65 parts by mass, even more preferably at most 50 parts by mass. By setting it below the upper limit value, low dielectric properties and low water absorption tend to be further improved.
The resin composition of this embodiment may contain only one type of thermosetting compound (C), or may contain two or more types of thermosetting compound (C). When two or more types are included, it is preferable that the total amount falls within the above range.

<Elastomer>
The resin composition of this embodiment may contain an elastomer.
In this embodiment, the elastomer is not particularly limited, and includes, for example, 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.
Moreover, although it may be a thermoplastic elastomer or a thermosetting elastomer, a thermoplastic elastomer is preferable.

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 resulting cured product tends to have better low dielectric properties. 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 it below the above upper limit, the solubility of the elastomer component in the resin composition tends to improve.
When the resin composition of this embodiment contains two or more types of elastomers, it is preferable that the number average molecular weight of the mixture satisfies the above range.

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

The thermoplastic elastomer (E) contains styrene monomer units. By including the styrene monomer unit, the solubility of the thermoplastic elastomer (E) in the resin composition is improved. Styrene monomers include styrene, α-methylstyrene, p-methylstyrene, divinylbenzene (vinylstyrene), N,N-dimethyl-p-aminoethylstyrene, N,N-diethyl-p-aminoethylstyrene, etc. Among these, from the viewpoint 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, more preferably in the range of 13 to 45% by mass, and more preferably in the range of 15 to 40% by mass. The range is more preferred. If the content of styrene monomer units is 50% by mass or less, the adhesiveness and tackiness to the substrate etc. will be better. Further, if it is 10% by mass or more, it is preferable because it is possible to suppress the increase in adhesion, it is difficult to form adhesive residue or stop marks, and the easy peelability between the adhesive surfaces tends to be good.
The thermoplastic elastomer (E) may contain only one type of styrene monomer unit, or may contain two or more types of styrene monomer units. When two or more types are included, it is preferable that the total amount is within the above range.
In addition, for the method of measuring the content of styrene monomer units in the thermoplastic elastomer (E), the description in International Publication No. 2017/126469 can be referred to, and the content thereof is incorporated herein. The same applies to the conjugated diene monomer unit, etc., which will be described later.

The thermoplastic elastomer (E) contains conjugated diene monomer units. By including the conjugated diene monomer unit, the solubility of the thermoplastic elastomer (E) in the resin composition is improved. The conjugated diene monomer is not particularly limited as long as it is a diolefin having one pair of conjugated double bonds. Conjugated diene monomers include, for example, 1,3-butadiene, 2-methyl-1,3-butadiene (isoprene), 2,3-dimethyl-1,3-butadiene, 1,3-pentadiene, 2-methyl- Examples include 1,3-pentadiene, 1,3-hexadiene, and farnesene, with 1,3-butadiene and/or isoprene being preferred, and 1,3-butadiene being more preferred.
The thermoplastic elastomer (E) may contain only one type of conjugated diene monomer unit, or may contain two or more types.

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

In the thermoplastic elastomer (E), all or some of the conjugated diene bonds of the thermoplastic elastomer may be hydrogenated, or may not be hydrogenated.

The thermoplastic elastomer (E) may or may not contain other monomer units in addition to the styrene monomer unit and the conjugated diene monomer unit. Examples of other monomer units include aromatic vinyl compound units other than styrene monomer units.
In the thermoplastic elastomer (E), the total of styrene monomer units and conjugated diene monomer units is preferably 90% by mass or more of all monomer units, more preferably 95% by mass or more, It is more preferably 97% by mass or more, even more preferably 99% by mass or more.
The thermoplastic elastomer (E) may contain only one type of styrene monomer unit and conjugated diene monomer unit, or may contain two or more types of each. When two or more types are included, it is preferable that the total amount falls within the above range.

The thermoplastic elastomer (E) may be a block polymer or a random polymer. In addition, even if it is a hydrogenated elastomer in which the conjugated diene monomer unit is hydrogenated, an unhydrogenated elastomer in which the conjugated diene monomer unit is not hydrogenated, or a partially hydrogenated elastomer in which the conjugated diene monomer unit is partially hydrogenated, good.
In one embodiment of the present embodiment, the thermoplastic elastomer (E) is a hydrogenated elastomer. Here, the hydrogenated elastomer means, for example, a thermoplastic elastomer in which the double bond based on the conjugated diene monomer unit is hydrogenated, and the hydrogenation rate (hydrogenation rate) is 100%. In addition, the purpose is to include 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 calculated from the measurement results of ¹ H-NMR spectrum measurement.
In one embodiment of the present embodiment, the thermoplastic elastomer (E) is an unhydrogenated elastomer. Here, unhydrogenated elastomer refers to the proportion of double bonds based on conjugated diene monomer units in the elastomer that are hydrogenated, that is, the hydrogenation rate (hydrogenation rate) is 20% or less. The purpose is to include things. The hydrogenation rate in the unhydrogenated elastomer is preferably 15% or less, more preferably 10% or less, even more preferably 5% or less.
On the other hand, a partially hydrogenated elastomer refers to a thermoplastic elastomer in which some of the double bonds based on conjugated diene monomer units are hydrogenated, and the hydrogenation rate (hydrogenation rate) is usually 80%. % or more than 20%.

Commercially available thermoplastic elastomers (E) used in this embodiment include SEPTON (registered trademark) 2104 manufactured by Kuraray Co., Ltd. and SEPTON (registered trademark) 2104 manufactured by Asahi Kasei Corporation. O. E. (registered trademark) S1606, S1613, S1609, S1605, manufactured by JSR Corporation, DYNARON (registered trademark) 9901P, TR2250, and the like.

When the resin composition of the present embodiment contains an elastomer (preferably a thermoplastic elastomer (E)), the content thereof is preferably 1 part by mass or more, and 3 parts by mass based on 100 parts by mass of the resin solid content. It is more preferably at least 7 parts by mass, even more preferably at least 7 parts by mass, even more preferably at least 10 parts by mass, and even more preferably at least 12 parts by mass. By setting it to the above lower limit or more, the low dielectric properties tend to be further improved. Further, 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, and preferably 25 parts by mass or less, based on 100 parts by mass of the resin solid content. More preferably, it is 21 parts by mass or less, even more preferably 18 parts by mass or less. By setting it below the upper limit value, heat resistance tends to be further improved.
The resin composition of this embodiment may contain only one type of elastomer, or may contain two or more types of elastomer. When two or more types are included, it is preferable that the total amount falls within the above range.

<Active ester compound>
The resin composition of this embodiment may contain an active ester compound.
The active ester compound is not particularly limited, and for example, 2 or more (preferably 2 to 12, more preferably 2 to 6, still more preferably 2 to 4, even more preferably 2 or 3, even more preferably 2 to 3) per molecule. Examples of 2) include compounds having an active ester group.
The active ester compound may be a linear or branched or cyclic compound. Among these, active ester compounds obtained by reacting a carboxylic acid compound and/or a thiocarboxylic acid compound with a hydroxy compound and/or a thiol compound are preferred, from the viewpoint of further improving the heat resistance of the obtained cured product. 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 preferable, and has a carboxylic acid compound and a phenolic hydroxyl group. An aromatic compound obtained by reacting with an aromatic compound and having two or more active ester groups in one molecule is more preferable, and a compound having two or more carboxylic acids in one molecule and a phenolic hydroxyl group. Particularly preferred are aromatic compounds obtained by reacting with aromatic compounds and having two or more active ester groups in one molecule.
Examples of the above carboxylic acid compounds include 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 them, from the viewpoint of further improving the heat resistance of the obtained cured product, one or more selected from the group consisting of succinic acid, maleic acid, itaconic acid, phthalic acid, isophthalic acid, and terephthalic acid is preferable, and isophthalic acid and More preferably, one or more types selected from the group consisting of terephthalic acid.
Examples of the above thiocarboxylic acid compound include one or more selected from thioacetic acid and thiobenzoic acid.
The above phenolic compounds or naphthol compounds include hydroquinone, resorcinol, bisphenol A, bisphenol F, bisphenol S, phenolphthalin, methylated bisphenol A, methylated bisphenol F, methylated bisphenol S, phenol, o-cresol, m- Cresol, p-cresol, catechol, α-naphthol, β-naphthol, 1,5-dihydroxynaphthalene, 1,6-dihydroxynaphthalene, 2,6-dihydroxynaphthalene, dihydroxybenzophenone, trihydroxybenzophenone, tetrahydroxybenzophenone, phloroglucin, One or more selected from the group consisting of benzenetriol, dicyclopentadienyl diphenol, and phenol novolak, and 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 A, methylated bisphenol F, methylated bisphenol S, catechol, α-naphthol, β-naphthol, 1,5-dihydroxynaphthalene, 1,6-dihydroxynaphthalene, 2,6-dihydroxynaphthalene , dihydroxybenzophenone, trihydroxybenzophenone, tetrahydroxybenzophenone, phloroglucin, benzenetriol, dicyclopentadienyl diphenol, and phenol novolac are preferred, and catechol, 1,5-dihydroxynaphthalene, 1,6-dihydroxynaphthalene, 2,6- More preferably, one or more selected from the group consisting of dihydroxynaphthalene, dihydroxybenzophenone, trihydroxybenzophenone, tetrahydroxybenzophenone, phloroglucin, benzenetriol, dicyclopentadienyl diphenol, and phenol novolak, 1,5-dihydroxynaphthalene, More preferably, one or more selected from the group consisting of 1,6-dihydroxynaphthalene, 2,6-dihydroxynaphthalene, dihydroxybenzophenone, trihydroxybenzophenone, tetrahydroxybenzophenone, dicyclopentadienyl diphenol, and phenol novolak, and dihydroxy One or more selected from the group consisting of benzophenone, trihydroxybenzophenone, tetrahydroxybenzophenone, dicyclopentadienyl diphenol, and phenol novolak (preferably selected from the group consisting of dicyclopentadienyl diphenol and phenol novolac) One or more types, more preferably dicyclopentadienyl diphenol) are particularly preferred.
Examples of the above-mentioned thiol compounds include one or more selected from the group consisting of benzenedithiol and triazinedithiol.
In addition, from the viewpoint of further improving the compatibility with the epoxy compound, the active ester compound is preferably a compound having two or more carboxylic acids in one molecule and containing an aliphatic chain, which further improves heat resistance. From the viewpoint of improvement, a compound having an aromatic ring is preferable. More specific active ester compounds include those described in JP-A No. 2004-277460.

The active ester compound may be a commercially available product or may be prepared by a known method. Commercially available products include compounds containing a dicyclopentadienyldiphenol structure (for example, EXB9451, EXB9460, EXB9460S, HPC-8000-65T (all manufactured by DIC), etc.), acetylated products of phenol novolac (for example, DC808 ( (manufactured by Mitsubishi Chemical Corporation)), and benzoylated products of phenol novolacs (for example, YLH1026, YLH1030, YLH1048 (all manufactured by Mitsubishi Chemical Corporation)), which improve the storage stability of varnishes, and when the resin composition is cured (cured EXB9460S is preferred from the viewpoint of further improving the low thermal expansion property of the product.

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. As a specific example, (a) a carboxylic acid compound or its halide, (b) a hydroxy compound, and (c) an aromatic monohydroxy compound, per mole of the carboxy group or acid halide group of (a), (b) (c) in a ratio of 0.05 to 0.75 mole of phenolic hydroxyl group and 0.25 to 0.95 mole of (c).

The active ester compound is preferably included within a range that does not impair the effects of the present invention. When the resin composition of this embodiment contains an active ester compound, it is preferably 1 part by mass or more, and preferably 90 parts by mass or less, based on 100 parts by mass of resin solid content in the resin composition. .
The resin composition in this embodiment may contain only one type of active ester compound, or may contain two or more types of active ester compounds. When two or more types are included, it is preferable that the total amount falls within the above range.
Moreover, the resin composition in this embodiment can also be configured to substantially not contain an active ester compound. "Substantially free" means that the content of the active ester compound is less than 1 part by mass, preferably less than 0.1 part by mass, per 100 parts by mass of resin solids in the resin composition. , more preferably less than 0.01 part by mass.

<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, with phosphorus-based flame retardants being preferred.
Known flame retardants can be used, such as brominated epoxy resin, brominated polycarbonate, brominated polystyrene, brominated styrene, brominated phthalimide, tetrabromobisphenol A, pentabromobenzyl (meth)acrylate, pentabromo Halogen flame retardants such as toluene, tribromophenol, hexabromobenzene, decabromodiphenyl ether, bis-1,2-pentabromophenylethane, chlorinated polystyrene, chlorinated paraffin, red phosphorus, tricresyl phosphate, triphenyl phosphate , cresyl diphenyl phosphate, trixylenyl phosphate, trialkyl phosphate, dialkyl phosphate, tris(chloroethyl) phosphate, phosphazene, 1,3-phenylenebis(2,6-dixylenyl phosphate), 10-(2,5- Phosphorous flame retardants such as (dihydroxyphenyl)-10H-9-oxa-10-phosphaphenanthrene-10-oxide, inorganic types such as aluminum hydroxide, magnesium hydroxide, partial boehmite, boehmite, zinc borate, and antimony trioxide. Examples include flame retardants, 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.

When the resin composition of the present embodiment contains a flame retardant, the content thereof is preferably 1 part by mass or more, and preferably 5 parts by mass or more, based on 100 parts by mass of resin solids in the resin composition. is more preferable. Further, 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.
One kind of flame retardant can be used alone or two or more kinds can be used in combination. When two or more types are used, the total amount falls within the above range.

<Other fillers>
In the resin composition of this embodiment, an inorganic filler that has not been treated with a surface treatment agent such as vinyl silane may or may not be used together. When used together, those listed as the inorganic filler (b2) can be used.
Moreover, in the resin composition of this embodiment, an organic filler may or may not be used together. Examples of the organic filler include styrene-type, butadiene-type, acrylic-type rubber powder, core-shell type rubber powder, silicone resin powder, silicone rubber powder, silicone composite powder, and the like. When an organic filler is used in combination, the content thereof is preferably 1 to 30 parts by mass based on 100 parts by mass of resin solid content in the resin composition.

<Dispersant>
The resin composition of this embodiment may contain a dispersant. As the dispersant, those commonly used for paints can be suitably used, and the type thereof is not particularly limited. As the dispersant, preferably a copolymer-based wetting and dispersing agent is used, and specific examples thereof include DISPERBYK®-110, 111, 161, 180, 2009, and 2152 manufactured by BYK Chemie Japan Co., Ltd. , 2155, BYK (registered trademark)-W996, W9010, W903, W940, etc.

When the resin composition of the present embodiment contains a dispersant, the lower limit of its content is preferably 0.01 parts by mass or more, and 0.01 parts by mass or more, based on 100 parts by mass of resin solids in the resin composition. It is more preferably 1 part by mass or more, and may be 0.3 parts by mass or more. Further, 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 3 parts by mass or less, based on 100 parts by mass of resin solids in the resin composition. It is more preferable that the amount is less than 1 part.
One type of dispersant can be used alone or two or more types can be used in combination. When two or more types are used, the total amount falls within the above range.

<Curing accelerator>
The resin composition of this embodiment may further contain a curing accelerator. Examples of the curing accelerator include, but are not limited to, imidazoles such as 2-ethyl-4-methylimidazole and triphenylimidazole; benzoyl peroxide, lauroyl peroxide, acetyl peroxide, parachlorobenzoyl peroxide, di- Organic peroxides such as tert-butyl-di-perphthalate; azo compounds such as azobisisobutyronitrile; N,N-dimethylbenzylamine, N,N-dimethylaniline, N,N-dimethyltoluidine, 2- Tertiary amines such as N-ethylanilinoethanol, tri-n-butylamine, pyridine, quinoline, N-methylmorpholine, triethanolamine, triethylenediamine, tetramethylbutanediamine, N-methylpiperidine; phenol, xylenol, Phenols such as cresol, resorcin, and catechol; lead naphthenate, lead stearate, zinc naphthenate, zinc octylate, manganese octylate, tin oleate, dibutyltin malate, manganese naphthenate, cobalt naphthenate, iron acetylacetonate, etc. Organic metal salts; these organic metal salts dissolved in hydroxyl group-containing compounds such as phenol and bisphenol; inorganic metal salts such as tin chloride, zinc chloride, and aluminum chloride; dioctyltin oxide, other alkyltin oxides, and alkyltin oxides Examples include organic tin compounds such as.
Preferred curing accelerators are imidazoles and organometallic salts, and it is more preferred to use both imidazoles and organometallic salts in combination.
The resin composition of the present embodiment can be configured to be substantially free of organic peroxides (eg, organic peroxides with 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, based on 100 parts by mass of resin solids contained in the resin composition of the present embodiment. . By setting it within such a range, a cured product with more excellent various performances can be obtained.
The resin composition of the present embodiment can be configured to be substantially free of an azo compound (for example, an azo compound 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, based on 100 parts by mass of resin solids contained in the resin composition of the present embodiment. . By setting it within such a range, a cured product with more excellent various performances can be obtained.

When the resin composition of the present embodiment contains a curing accelerator, the lower limit of its content is preferably 0.005 parts by mass or more, based on 100 parts by mass of resin solids in the resin composition, and 0. It is more preferably .01 part by mass or more, and even more preferably 0.1 part by mass or more. Further, 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, based on 100 parts by mass of resin solids in the resin composition. It is more preferably less than parts by mass.
The curing accelerator 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.

<Solvent>
The resin composition of this embodiment may contain a solvent, and preferably contains an organic solvent. When containing a solvent, the resin composition of the present 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 with the solvent. The solvent is not particularly limited as long as it is a polar organic solvent or a non-polar organic solvent that can dissolve or be compatible with at least a portion, preferably all, of the various resin solids mentioned above. Examples of the polar organic solvent include ketones, etc. (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, ethyl acetate, butyl acetate, acetic acid) isoamyl, ethyl lactate, methyl methoxypropionate, methyl hydroxyisobutyrate, etc.), amides (e.g., dimethoxyacetamide, dimethylformamide, etc.), and nonpolar organic solvents include aromatic hydrocarbons (e.g., toluene, xylene, etc.).
One kind of solvent can be used alone or two or more kinds can be used in combination. When two or more types are used, the total amount falls within the above range.

<Other ingredients>
The resin composition of the present embodiment may contain, in addition to the above-mentioned components, various polymeric compounds such as thermoplastic resins and oligomers thereof, and various additives. Additives include ultraviolet absorbers, antioxidants, photopolymerization initiators, optical brighteners, photosensitizers, dyes, pigments, thickeners, fluidity regulators, lubricants, antifoaming agents, leveling agents, and gloss. agents, polymerization inhibitors, etc. These additives can be used alone or in combination of two or more.

<Application>
The resin composition of this embodiment is used as a cured product. Specifically, the resin composition of this embodiment is suitable as a low dielectric constant material and/or a low dielectric loss tangent material as a resin composition for electronic materials such as insulating layers of printed wiring boards, materials for semiconductor packages, etc. Can be used. The resin composition of this embodiment can be suitably used as a material for prepreg, a metal foil-clad laminate using prepreg, a resin composite sheet, and a printed wiring board.

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 the cavity resonator perturbation method is preferably 3.50 or less, more preferably 2.81 or less, and 2.78. It is more preferable that it is the following. Although the lower limit of the dielectric constant (Dk) is not particularly determined, for example, 2.0 or more is practical.
Moreover, it is preferable that the resin composition of this embodiment has a low dielectric loss tangent (Df) when molded into a cured plate with 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, and preferably 0.0020 or less. More preferably, it is 0.0018 or less, even more preferably. Although the lower limit value of the dielectric loss tangent (Df) is not particularly determined, for example, 0.0001 or more is practical.
More specifically, the dielectric constant (Dk) and dielectric loss tangent (Df) of the cured plate are measured by the method described in the Examples described below.

The resin composition of this embodiment is used as a layered material (including film-like, sheet-like, etc.) such as prepreg, resin composite sheet, etc., which becomes an insulating layer of a printed wiring board. In this case, 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. In addition, the thickness of the above-mentioned layered material means the thickness including the glass cloth, for example, when the resin composition of the present embodiment is impregnated into a glass cloth or the like.
The material formed from the resin composition of this embodiment may be used for forming a pattern by exposure and development, or may be used for applications that are not exposed and developed. It is particularly suitable for applications that do not involve exposure and development.

<<Prepreg>>
The prepreg of this embodiment is formed from a base material (prepreg base material) and the resin composition of this embodiment. The prepreg of the present embodiment can be produced by, for example, applying the resin composition of the present embodiment to a base material (for example, impregnating and/or coating it), and then heating it (for example, drying it at 120 to 220°C for 2 to 15 minutes). etc.) by semi-curing. In this case, the amount of the resin composition adhered to the base material, that is, the amount of the resin composition (including the inorganic filler (B)) relative to the total amount of prepreg after semi-curing, is preferably in the range of 20 to 99% by mass, More preferably, the content is in the range of 20 to 80% by mass.

The base material is not particularly limited as long as it is a base material used for various printed wiring board materials. Examples of the material of the base material include glass fiber (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 (eg, quartz, etc.), and organic fibers (eg, polyimide, polyamide, polyester, liquid crystal polyester, polytetrafluoroethylene, etc.). The form of the base material is not particularly limited, and examples thereof include woven fabric, nonwoven fabric, roving, chopped strand mat, surfacing mat, and the like. These base materials may be used alone or in combination of two or more. Among these base materials, from the viewpoint of dimensional stability, woven fabrics subjected to ultra-opening treatment and packing treatment are preferable, and from the viewpoints of strength and low water absorption, the base material has a thickness of 200 μm or less, a mass of 250 g/ A glass woven fabric having a size of m ² or less is preferable, and from the viewpoint of moisture absorption and heat resistance, a glass woven fabric surface-treated with a silane coupling agent such as epoxy silane or amino silane is preferable. From the viewpoint of electrical properties, a low dielectric glass cloth made of glass fibers exhibiting a low dielectric constant and a low dielectric loss tangent, such as L-glass, NE-glass, and Q-glass, is more preferable.
Examples of the base material having a low dielectric constant include a base material having a dielectric constant of 5.0 or less (preferably 3.0 to 4.9). Examples of the low dielectric loss tangent base material include base materials 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.

<<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 metal foil disposed on one or both sides of the layer formed from the prepreg. As a method for producing the metal foil-clad laminate of this embodiment, for example, at least one prepreg of this embodiment is arranged (preferably two or more prepregs are stacked), metal foil is arranged on one or both sides of the prepreg, and laminated molding is performed. One method is to do so. More specifically, it can be produced by arranging a metal foil such as copper or aluminum on one or both sides of a prepreg and laminating it. The number of prepreg sheets is preferably 1 to 10 sheets, more preferably 2 to 10 sheets, and even more preferably 2 to 9 sheets. The metal foil is not particularly limited as long as it is used as a material for 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 about 1.5 to 70 μm. Examples of the molding method include methods normally used when molding laminates for printed wiring boards, and more specifically, using a multistage press machine, a multistage vacuum press machine, a continuous molding machine, an autoclave molding machine, etc. Examples include a method of lamination molding at a temperature of about 180 to 350° C., a heating time of about 100 to 300 minutes, and a surface pressure of about 20 to 100 kg/cm ² . Furthermore, a multilayer board can be obtained by laminating and molding a combination of the prepreg of this embodiment and a separately produced wiring board for an inner layer. As a method for manufacturing a multilayer board, for example, copper foil of about 35 μm is placed on both sides of one sheet of prepreg of this embodiment, and after lamination is formed using the above-mentioned forming method, an inner layer circuit is formed, and this circuit is coated with black. After that, the inner layer circuit board and the prepreg of this embodiment are alternately placed one by one, and then copper foil is placed on the outermost layer, and the above conditions are met. A multilayer board can be produced by lamination molding, preferably under vacuum. The metal foil-clad laminate of this embodiment can be suitably used as a printed wiring board.

The metal foil-clad laminate of the present embodiment preferably has a low water absorption rate after being left for 5 hours at 121° C. and in the presence of saturated steam at 2 atm (PCT treatment: moisture absorption treatment using a pressure cooker tester). . Specifically, after removing the metal foil by etching, the water absorption rate of the cured product obtained by PCT treatment at 121 ° C. for 5 hours is preferably 2.00% by mass or less, and preferably 1.80% by mass or less. is more preferable, 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.

Further, it is preferable that the cured plate from which the metal foil has been removed by etching is subjected to a PCT treatment at 121° C. for 5 hours in the presence of saturated steam at 2 atm, so that the dielectric constant (Dk) is low. 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.
Further, it is preferable that the cured plate from which the metal foil has been removed by etching is subjected to a PCT treatment at 121° C. for 5 hours in the presence of saturated steam at 2 atm, and the dielectric loss tangent (Df) 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 even more preferably 0.0100 or less. This is particularly preferred. The lower limit is not particularly limited, but is, for example, 0.0050 or more.
The dielectric constant (Dk), the dielectric loss tangent (Df), and the PCT treatment are as described in Examples described later.

As described above, the cured product of the resin composition for electronic materials obtained using the resin composition of the present embodiment (resin composition consisting of a combination of specific components) has not only dielectric properties but also moisture absorption and heat resistance, It can have excellent dielectric properties after moisture absorption treatment. It is also possible to use a resin composition with low water absorption.

<<Printed wiring board>>
The printed wiring board of the present embodiment is a printed wiring board including an insulating layer and a conductor layer disposed on the surface of the insulating layer, the insulating layer being formed from the resin composition of the present embodiment. and a layer formed from the prepreg of this embodiment. Such a printed wiring board can be manufactured according to a conventional method, and the manufacturing method is not particularly limited. An example of a method for manufacturing a printed wiring board will be shown 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. The surface of the inner layer circuit of this inner layer board is subjected to surface treatment to increase adhesive strength as necessary, and then the required number of sheets of prepreg described above are layered on the surface of the inner layer circuit, and then metal foil for the outer layer circuit is laminated on the outside. Then heat and press to form an integral mold. In this way, a multilayer laminate is produced in which an insulating layer made of a base material and a cured resin composition is formed between the inner layer circuit and the metal foil for the outer layer circuit. Next, after drilling holes for through holes and via holes in this multilayer laminate, a plated metal film is formed on the wall of the hole to conduct the inner layer circuit and the metal foil for the outer layer circuit, and then the outer layer circuit is formed. A printed wiring board is manufactured by performing an etching process on metal foil to form an outer layer circuit.

The printed wiring board obtained in the above manufacturing example has an insulating layer and a conductor layer formed on the surface of the insulating layer, and the insulating layer is made of the resin composition of the present embodiment described above and/or a cured product thereof. The configuration includes That is, the prepreg of the present embodiment described above (for example, the prepreg formed from the base material and the resin composition of the present embodiment impregnated or applied thereto), the resin composition of the metal foil-clad laminate of the present embodiment described above The layer formed from the material becomes the insulating layer of this embodiment.
The present embodiment also relates to a semiconductor device including the printed wiring board. For details of the semiconductor device, the descriptions in paragraphs 0200 to 0202 of JP-A-2021-021027 can be referred to, and the contents thereof are incorporated into this specification.

<<Resin composite sheet>>
The resin composite sheet of this embodiment includes a support and a layer formed from the resin composition of this embodiment 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. The method for producing the resin composite sheet is not particularly limited, but for example, the resin composite sheet may be produced by applying (coating) a solution in which the resin composition of the present embodiment described above is dissolved in a solvent to a support and drying it. There are several ways to obtain it.

Examples of the support used here include polyethylene film, polypropylene film, polycarbonate film, polyethylene terephthalate film, ethylenetetrafluoroethylene copolymer film, and release films in which a release agent is applied to the surface of these films. Examples include organic film base materials such as polyimide film, conductive foils such as copper foil and aluminum foil, plate-like materials such as glass plates, SUS (Steel Use Stainless) plates, and FRP (Fiber-Reinforced Plastics). It is not particularly limited.

Examples of the coating method (coating method) include a method in which a solution of the resin composition of the present embodiment dissolved in a solvent is coated onto the support using a bar coater, die coater, doctor blade, Baker applicator, etc. It will be done. Further, after drying, the support can be peeled off or etched from the resin composite sheet in which the support and the resin composition are laminated, thereby forming a single layer sheet. Note that the support can be used by supplying a solution in which the resin composition of the present embodiment described above is dissolved in a solvent into a mold having a sheet-like cavity and drying it to form it into a sheet. It is also possible to obtain a single layer sheet.

In the production of the single-layer sheet or resin composite sheet of this embodiment, the drying conditions for removing the solvent are not particularly limited, but if the temperature is low, the solvent tends to remain in the resin composition, and if the temperature is high, Since curing of the resin composition progresses, the temperature is preferably 20° C. to 200° C. for 1 to 90 minutes. Further, the single layer sheet or the resin composite sheet can be used in an uncured state where the solvent is simply dried, or it can be used in a semi-cured (B-staged) state if necessary. Further, the thickness of the resin layer in the single-layer sheet or resin composite sheet of this embodiment can be adjusted by the concentration of the solution of the resin composition of this embodiment used for application (coating) and the coating thickness, and there are no particular limitations. However, in general, as the coating thickness increases, solvent tends to remain during drying, so 0.1 to 500 μm is preferable.

The present invention will be explained in more detail with reference to Examples below. The materials, usage amounts, ratios, processing details, processing procedures, etc. shown in the following examples can be changed as appropriate 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 equipment used in the examples is difficult to obtain due to discontinuation or the like, measurements can be made using other equipment with equivalent performance.

<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. The mixture was placed in a reactor, and 600 mmol of boron trifluoride diethyl ether complex was added at 70°C, followed by reaction for 4 hours. After stopping the polymerization reaction with an aqueous sodium hydrogen carbonate solution, the oil layer was washed three times with pure water and devolatilized under reduced pressure at 60°C to recover a polymer (va) having a structural unit represented by formula (V). did. The obtained polymer (va) having a structural unit represented by formula (V) was weighed, and 860.8 g of a polymer (va) having a structural unit represented by formula (V) was obtained. It was confirmed.

The obtained 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 Mw/Mn of 14.9. there were. By performing ¹³ C-NMR and ¹ H-NMR analysis, it was found that the polymer (va) having the structural unit represented by formula (V) had resonance lines derived from each monomer unit used as a raw material. observed. Based on the NMR measurement results and the GC analysis results, the proportion of each monomer unit (constituent unit derived from each raw material) in the polymer (va) having the structural unit represented by formula (V) is as follows. was calculated.
Structural unit derived from divinylbenzene: 20.9 mol% (24.3 mass%)
Structural unit derived from ethylvinylbenzene: 9.1 mol% (10.7 mass%)
Structural unit derived from styrene: 70.0 mol% (65.0 mass%)
Furthermore, the amount of structural units having residual vinyl groups derived from divinylbenzene was 16.7 mol% (18.5% by mass).

<Synthesis Example 2 Synthesis of α-naphthol aralkyl cyanate ester compound (SNCN)>
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 is 1 to 5.) 0.47 mol (OH group (converted) 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 0.93 mol cyanogen chloride chloroform solution charged in the reactor, and after the dropwise addition was completed, the mixture was stirred for 30 minutes. Thereafter, a mixed solution of 0.1 mol of triethylamine and 30 g of chloroform was added dropwise into the reactor and stirred for 30 minutes to complete the reaction. After the by-produced triethylamine hydrochloride was filtered off from the reaction solution, the resulting filtrate was washed with 500 mL of 0.1N hydrochloric acid, and then washed with 500 mL of water four times. After drying this with sodium sulfate, it was 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) (in the formula R ^C1 to R ^C4 are all hydrogen atoms, and n ^c is a mixture of 1 to 5). When the obtained α-naphthol aralkyl cyanate ester compound was analyzed by infrared absorption spectrum, absorption of the cyanate ester group was confirmed at around 2264 cm ⁻¹ .

<Synthesis Example 3 Synthesis of modified polyphenylene ether compound>
<<Synthesis of bifunctional phenylene ether oligomer>>
9.36 g (42.1 mmol) of CuBr ₂ and 1.81 g (10 mmol) of N,N'-di-t-butylethylenediamine were placed in a 12 L vertical reactor equipped with a stirrer, thermometer, air inlet tube, and baffle plate. .5 mmol), n-butyldimethylamine 67.77 g (671.0 mmol), and toluene 2,600 g were stirred at a reaction temperature of 40°C. 3,3',5,5'-hexamethyl-(1,1'-biphenol)-4,4'-diol 129.32 g (0.48 mol), 2,6-dimethylphenol 878.4 g (7.2 mol) A mixed solution of 1.22 g (7.2 mmol) of N,N'-di-t-butylethylenediamine and 26.35 g (260.9 mmol) of n-butyldimethylamine was mixed with nitrogen and air to give an oxygen concentration of 8. A mixed gas adjusted to volume % was added dropwise over 230 minutes while bubbling at a flow rate of 5.2 L/min, followed by stirring. After the dropwise addition was completed, 1,500 g of water in which 48.06 g (126.4 mmol) of tetrasodium ethylenediaminetetraacetate was dissolved was added to stop the reaction. The aqueous layer and the organic layer were separated, and the organic layer was washed with a 1N aqueous hydrochloric acid solution and then with pure water. The obtained solution was concentrated to 50% by mass using an evaporator to obtain 1981 g of a toluene solution of a bifunctional phenylene ether oligomer (resin "A"). Resin "A" had a number average molecular weight in terms of polystyrene determined by GPC of 1,975, a weight average molecular weight in terms of polystyrene determined by GPC of 3,514, and a hydroxyl equivalent of 990.

<<Synthesis of modified polyphenylene ether compound>>
In a reactor equipped with a stirring device, a thermometer, and a reflux tube, 833.4 g of a toluene solution of resin "A", 76.7 g of vinylbenzyl chloride (manufactured by AGC Seimi Chemical Co., Ltd., "CMS-P"), 1 methylene chloride, 600g of benzyldimethylamine, 6.2g of benzyldimethylamine, 199.5g of pure water, and 83.6g of a 30.5% by mass NaOH aqueous solution were charged, and the mixture was stirred at a reaction temperature of 40°C. After stirring for 24 hours, the organic layer was washed with a 1N aqueous hydrochloric acid solution and then with pure water. The obtained solution was concentrated using an evaporator, solidified by dropping into methanol, and the solid was collected 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 in terms of polystyrene determined by GPC of 2,250, a weight average molecular weight in terms of polystyrene determined by GPC of 3,920, and a vinyl group equivalent of 1189 g/vinyl group.

<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). Liquid pump (manufactured by Shimadzu Corporation, LC-20AD), differential refractive index detector (manufactured by Shimadzu Corporation, RID-10A), GPC column (manufactured by Showa Denko Corporation, GPC KF-801, 802, 803, 804) The experiment was carried out using tetrahydrofuran as the solvent, a flow rate of 1.0 mL/min, a column temperature of 40° C., and a calibration curve using monodisperse polystyrene.

Example 1
5 parts by mass of a maleimide compound (manufactured by Nippon Kayaku Co., Ltd., MIR-3000-70MT, corresponding to the compound represented by formula (M3)), a maleimide compound (ma) having the structure shown below (manufactured by DIC Corporation, “NE- X-9470S", corresponding to the compound represented by formula (M1)) 29 parts by mass, 30 parts by mass of the polymer (va) having the structural unit represented by formula (V) obtained in Synthesis Example 1, water 15 parts by mass of styrene-doped thermoplastic elastomer (SEBS, block copolymer, SEPTON2104, Mn83000, manufactured by Kuraray Co., Ltd.), cyanate ester compound (α-naphthol aralkyl cyanate ester compound obtained in Synthesis Example 2 (SNCN) )) 5 parts by mass, 15 parts by mass of phosphorus flame retardant (PX-200, Daihachi Kagaku Kogyo Co., Ltd.), 1 part by mass of N-phenylmaleimide (manufactured by Tokyo Kasei Kogyo Co., Ltd., product number: P0900), wetting and dispersing agent ( BYK Co., Ltd., BYK-2009) 0.3 parts by mass, wetting and dispersing agent (DISPERBYK-161, BYK-Chemie Japan Co., Ltd.) 0.5 parts by mass, vinylsilane-treated silica methyl ethyl ketone (MEK) slurry (SC2050MNU (product name) ), median diameter 0.5 μm, non-volatile content 70% by mass, manufactured by Admatex Co., Ltd.) were dissolved and dispersed in methyl ethyl ketone and mixed to obtain a varnish. Note that each amount added above indicates the amount of solid content. Furthermore, the vinyl silane-treated silica corresponds to the inorganic filler (B) containing an organic group containing a carbon-carbon unsaturated bond.

maleimide compound (ma)
n is an integer from 1 to 20.

<Manufacture of a cured plate test piece with a thickness of 0.8 mm>
A mixed resin powder was obtained by evaporating the solvent from the obtained varnish. A mold with a side of 100 mm and a thickness of 0.8 mm was filled with mixed resin powder, 12 μm copper foil (3EC-M2S-VLP, manufactured by Mitsui Mining & Mining Co., Ltd.) was placed on both sides, and the pressure was 30 kg/cm ² and the temperature was Vacuum pressing was performed at 220° C. for 120 minutes to obtain a cured plate with a side of 100 mm and a thickness of 0.8 mm.
Using the obtained cured plate, the relative permittivity (Dk), dielectric loss tangent (Df), water absorption after PCT treatment described below, relative permittivity (Dk) after PCT treatment, and dielectric loss tangent (Df) , as well as evaluation of moisture absorption and heat resistance. The evaluation results are shown in Table 1.

<Measurement method and evaluation method>
(1) Relative permittivity (Dk) and dielectric loss tangent (Df)
After removing the copper foil of the cured plate by etching and drying it at 120 ° C. for 60 minutes, the relative dielectric constant (Dk) and dielectric loss tangent (Df) after drying at 10 GHz were determined using a perturbation method cavity resonator. It was measured. The measurement temperature was 23°C.
The perturbation method cavity resonator used was Agilent 8722ES manufactured by Agilent Technologies.
It was evaluated as follows.
(Dk)
A: 2.78 or less B: More than 2.78 and less than 2.81 C: More than 2.81 (Df)
A: 0.0020 or less B: More than 0.0020

(2) PCT treatment (moisture absorption treatment using a pressure cooker tester)
The copper foil of the cured plate was removed by etching, and left to stand for 5 hours at 121°C in the presence of saturated steam at 2 atm using a pressure cooker tester. and Df (Dk and Df after moisture absorption) were measured. The pressure cooker tester used was model PC-3 manufactured by Hirayama Seisakusho Co., Ltd.
It was evaluated as follows.
(Dk after PCT treatment)
A: 3.20 or less B: More than 3.20 (Df after PCT treatment)
A: 0.0110 or less B: More than 0.0110 Further, the copper foil of the cured plate was removed by etching to obtain a sample for water absorption measurement. After drying the obtained sample at 120° C. for 60 minutes, 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 atm using a pressure cooker tester, and then the mass of the sample after PCT treatment was measured. The water absorption rate of the sample for measuring water absorption rate after PCT treatment was calculated from 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)
Cut the cured board into 50 mm x 50 mm (downsizing), remove all the copper foil on one side by etching, and remove half of the copper foil on the other side by etching to make it hygroscopic and heat resistant. A sample for sex measurement was obtained. The obtained sample was dried at 120°C for 60 minutes, then left to stand for 5 hours at 121°C in the presence of saturated steam at 2 atm using a pressure cooker tester, and then placed in a solder bath at 260°C for 30 seconds. The samples were dipped and visually observed for any abnormalities in appearance. For each measurement, three sheets were tested for each sheet, and if there were no abnormalities in appearance among the three sheets, it would be rated "A," and if 1 or 2 sheets were found to have abnormalities in appearance, it would be rated "B." When three abnormalities were observed, the evaluation was rated as "C". The appearance was observed by five experts and a majority vote was taken.

Example 2
In Example 1, the methyl ethyl ketone slurry of vinyl silane-treated silica was changed to the same amount of another methyl ethyl ketone slurry of vinyl silane-treated silica (manufactured by Admatex Co., Ltd., 5SV-CM8), and the other procedures were the same.

Example 3
In Example 1, the polymer (va) having the 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, and the other things were the same. I went to

Comparative example 1
In Example 1, the methyl ethyl ketone slurry of vinyl silane-treated silica was changed to the same amount of methyl ethyl ketone slurry of epoxy silane-treated silica (manufactured by Admatex Co., Ltd., SC2050MB), and the other procedures were the same.

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 thermoplastic elastomer (SEPTON2104), phosphorus flame retardant (PX-200) ) 15 parts by mass, 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 methyl ethyl ketone (MEK) slurry of vinylsilane-treated silica (SC2050MNU). The mixture was dissolved, dispersed, and mixed to obtain a varnish. Evaluation was made in the same manner as in Example 1.

Claims (18)

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;
The vinyl group equivalent weight of the polymer (A), which includes the polymer (A) and another thermosetting compound (C) that does not correspond to the inorganic filler (B), is 200 g/eq. More than 1200g/eq. The following is
Among the inorganic fillers (B), a compound containing an organic group containing a carbon-carbon unsaturated bond is defined as a compound (b1), and the organic group containing a carbon-carbon unsaturated bond is removed from the inorganic filler (B). When the material is used as an inorganic filler (b2),
A resin composition in which the number of functional groups of the compound (b1) is more than 1 times and not more than 5 times the number of functional groups of the inorganic filler (b2),
Based on 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 10 to 500 parts by mass,
The content of the other thermosetting compound (C) is 5 to 95 parts by mass,
The polymer (A) contains the structural unit (a) derived from a divinyl aromatic compound in a proportion of 3 mol% or more and 40 mol% or less, and of all the structural units excluding the terminal, a structure containing an aromatic ring The unit is 90 mol% or more,
The other curable compound (C) is a compound represented by formula (M1), a compound represented by formula (M3), a compound represented by formula (1), and a compound represented by formula (OP-1). is a mixture containing a compound that is
Resin composition.

(In formula (V), Ar represents an aromatic hydrocarbon linking group. * represents the bonding position.)

(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 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 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 represents 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, or an aryl group having 6 to 10 carbon atoms. , represents 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. )

(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 to 10.)

(In formula (1), R3 ^each independently represents a hydrogen atom or a methyl group, and n3 represents an integer of 1 or more.)

(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 are each independently, Represents a hydrogen atom, an alkyl group, an alkenyl group, or an alkynyl group, 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.) The resin composition according to claim 1, wherein the polymer (A) has a weight average molecular weight of 1,000 to 160,000. The resin composition according to claim 1, wherein the organic group containing a carbon-carbon unsaturated bond has a structure of CH ₂ =C(X)- (X is a hydrogen atom or a methyl group). The resin composition according to claim 1, wherein the organic group containing a carbon-carbon unsaturated bond includes at least one selected from the group consisting of a vinyl group, an allyl group, an acrylic group, and a methacryl group. The resin composition according to claim 1, wherein the inorganic filler (B) is an inorganic filler in which the organic group containing the carbon-carbon unsaturated bond is bonded via a silicon atom. The inorganic filler (B) is 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. The resin composition according to claim 1, comprising: The resin composition according to claim 1, wherein the inorganic filler (B) contains silica. The resin composition according to claim 1, wherein the inorganic filler (B) is obtained by reacting silica with an organosilicon compound having an organic group containing the carbon-carbon unsaturated bond in a slurry state. The weight average molecular weight of the polymer (A) is 1,000 to 160,000,
The organic group containing a carbon-carbon unsaturated bond includes at least one selected from the group consisting of a vinyl group, an allyl group, an acrylic group, and a methacryl group,
The inorganic filler (B) is an inorganic filler in which the organic group containing the carbon-carbon unsaturated bond is bonded via a silicon atom,
The resin composition according to claim 1, wherein the inorganic filler (B) contains silica. The weight average molecular weight of the polymer (A) is 1,000 to 160,000,
The organic group containing a carbon-carbon unsaturated bond includes at least one selected from the group consisting of a vinyl group, an allyl group, an acrylic group, and a methacryl group,
The inorganic filler (B) is an inorganic filler in which the organic group containing the carbon-carbon unsaturated bond is bonded via a silicon atom, and the inorganic filler (B) in a slurry state The resin composition according to claim 1, which is obtained by reacting an organosilicon compound having an organic group containing a carbon-carbon unsaturated bond with silica. The resin composition according to claim 1, further comprising a styrenic thermoplastic elastomer. The resin composition according to claim 1, further comprising an unhydrogenated styrenic thermoplastic elastomer. The resin composition according to claim 1, wherein the compound (b1) is vinylsilane. A prepreg formed from a base material and the resin composition according to any one of claims 1 to 13 . A metal foil-clad laminate comprising at least one layer formed from the prepreg according to claim 14 and a metal foil disposed on one or both sides of the layer formed from the prepreg. A resin composite sheet comprising a support and a layer formed from the resin composition according to any one of claims 1 to 13 disposed on the surface of the support. A printed wiring board comprising an insulating layer and a conductor layer disposed on a surface of the insulating layer, the insulating layer being formed from the resin composition according to any one of claims 1 to 13 . Printed wiring board, including layers. A semiconductor device comprising the printed wiring board according to claim 17 .