JP2019178310A - Curable resin composition, cured article thereof, curable composite material, metal foil with resin, and resin material for circuit board material - Google Patents

Abstract

To provide a novel curable resin composition capable of providing a resin cured article or a molded body having improvement in dielectric property, long term environmental reliability, heat resistance, and adhesion to a copper foil, a film consisting of the novel curable resin composition, a cured body obtained by curing the same, a curable composite material consisting of the curable resin composition and a substrate, a cured body thereof, a laminate consisting of the cured body and a metal foil, and a copper foil with a resin.SOLUTION: There is provided a curable resin composition containing a polyfunctional vinyl aromatic copolymer containing a repeating unit derived from a divinyl aromatic compound of 2 mol% or more and less than 95 mol%, and repeating unit derived from a monovinyl aromatic compound of less than 98 mol% and 5 mol% or more, a thermoplastic resin (B), and/or a thermosetting crosslinking agent, and having dielectric loss tangent (Df) of the resin composition after curing of 0.0025 or less, peak temperature of a tanδ curve in a dynamic viscoelasticity measurement (DMA, tensile test method) of 200°C or higher, and 90° peak strength to the copper foil of 0.5 kN/m or more.SELECTED DRAWING: None

Description

  The present invention relates to a novel curable resin composition capable of providing a cured resin or molded article having improved dielectric properties, long-term environmental reliability, heat resistance, and adhesion to copper foil. Furthermore, this invention relates to the film which consists of the said curable resin composition, and the hardening body obtained by hardening | curing this. Furthermore, this invention relates to the curable composite material which consists of the said curable resin composition and a base material, its hardening body, the laminated body which consists of this hardening body and metal foil, and copper foil with resin.

  With the increase in information traffic in recent years, information communication in the high frequency band has been actively performed, and in order to reduce the transmission loss in the higher frequency band, more excellent electrical characteristics, in particular, low dielectric constant and low There is a need for an electrically insulating material having a dielectric loss tangent. In addition, since these materials are used in harsh environments, long-term environmental reliability is required. Furthermore, LSIs have been increased in speed, integration, memory capacity, etc., and along with this, various electronic components have been rapidly reduced in size, weight and thickness. For this reason, in terms of materials, in addition to heat resistance and electrical characteristics, more excellent moldability is required.

  Conventionally, thermosetting resins such as phenol resins, epoxy resins, and polyimide resins have been used for printed wiring boards. Although these resins have various performances in a well-balanced manner, the dielectric properties in the high frequency region are insufficient. As a new material for solving this problem, polyphenylene ether has attracted attention, and its application to a copper-clad laminate has been attempted (for example, see Patent Document 1).

  Patent document 2 (WO 2005/73264) discloses a polyphenylene ether oligomer having a specific vinyl group at both ends, and a polyfunctional vinyl aromatic having a structural unit derived from a monomer composed of a divinyl aromatic compound and an ethyl vinyl aromatic compound. A curable resin composition comprising a group copolymer is disclosed. However, it is insufficient in terms of dielectric properties for use as a substrate material in the field of advanced electronic equipment.

  On the other hand, Patent Document 3 (WO2016 / 104748) discloses a soluble polyfunctional vinyl aromatic copolymer excellent in dielectric properties suitable for a substrate application. The adhesion is not disclosed. A composition comprising a polyfunctional vinyl aromatic copolymer and a poly (phenylene ether) containing a hydroxyl group blocked with an ethylenic unsaturation-containing compound is also disclosed in this patent document, and can withstand use. However, the dielectric properties deteriorate and the performance is not sufficient.

JP 2005-8829 A WO2005 / 73264 WO2016 / 104748

  An object of the present invention is to provide a novel curable resin composition capable of providing a cured resin or a molded product having improved dielectric properties, long-term environmental reliability, heat resistance, and adhesion to copper foil. And The present invention also provides a film comprising the novel curable resin composition, a cured product obtained by curing the film, a curable composite material comprising the curable resin composition and a substrate, a cured product thereof, and curing. It aims at providing the laminated body which consists of a body and metal foil, and copper foil with resin.

  The curable resin composition of the present invention contains 2 mol% or more and less than 95 mol% of a repeating unit derived from a divinyl aromatic compound (a) and a repeating unit derived from a monovinyl aromatic compound (b). Resin composition containing polyfunctional vinyl aromatic copolymer (A) and thermoplastic resin (B) and / or thermosetting crosslinking agent (C) containing less than 98 mol% and 5 mol% or more The dielectric loss tangent (Df) of the cured resin composition is 0.0025 or less, and the peak temperature of the tan δ curve in the dynamic viscoelasticity measurement (DMA, tensile test method) is 200 ° C. or higher. And the 90 degree peel strength with respect to copper foil of the said thermosetting resin composition hardened | cured material is 0.5 kN / m or more, It is characterized by the above-mentioned.

  In the curable resin composition of the present invention, preferably, the polyfunctional vinyl aromatic copolymer (A) contains an unsaturated hydrocarbon group derived from (a), and the number average molecular weight Mn is 300 to 300. 100,000 and a molecular weight distribution (Mw / Mn) represented by the ratio of the weight average molecular weight Mw to the number average molecular weight Mn is 100.0 or less, and toluene, xylene, tetrahydrofuran, dichloroethane or chloroform It is soluble.

  Furthermore, regarding the flame retardant (D) and / or filler (E), the total content of (D) and (E) is 20% by weight or more and 95% by weight or less with respect to the entire thermosetting resin composition. It can contain in the range of.

  Moreover, this invention is a hardened | cured material formed by hardening | curing said curable resin composition. Furthermore, this invention is a film which consists of said curable resin composition.

  Further, the present invention is a curable composite material comprising the above curable resin composition and a base material, the base material being contained at a ratio of 5 to 90% by weight, and this Is a cured composite material obtained by curing Furthermore, the present invention is a laminate comprising the cured composite material layer and a metal foil layer.

  Moreover, this invention is a metal foil with resin characterized by having the film | membrane of said curable resin composition on the single side | surface of metal foil. Furthermore, this invention is a varnish for circuit board materials formed by dissolving said curable resin composition in an organic solvent.

  The novel curable resin composition obtained by the present invention can provide a cured resin product or molded article having improved dielectric properties, long-term environmental reliability, heat resistance, and adhesion to copper foil. The present invention also provides a film comprising the novel curable resin composition, a cured product obtained by curing the film, a curable composite material comprising the curable resin composition and a substrate, a cured product thereof, and curing. It becomes possible to provide also about the laminated body which consists of a body and metal foil, and copper foil with resin.

The curable resin composition of the present invention contains a repeating unit derived from the divinyl aromatic compound (a) in an amount of 2 mol% or more and less than 95 mol%, and a repeating unit derived from the monovinyl aromatic compound (b). The polyfunctional vinyl aromatic copolymer (A) and the thermoplastic resin (B) and / or the thermosetting cross-linking agent (C) containing less than 98 mol% and 5 mol% or more are contained as essential components.
The polyfunctional vinyl aromatic copolymer is also referred to as component (A). First, the component (A) will be described.

This polyfunctional vinyl aromatic copolymer contains a repeating unit (a) derived from a divinyl aromatic compound, a repeating unit (b) derived from a monovinyl aromatic compound, and a repeating unit derived from a divinyl aromatic compound. The repeating unit (a1) represented by the above formula (a1) is contained as a part of the unit (a). In the formula (a1), R1 represents an aromatic hydrocarbon group having 6 to 30 carbon atoms.
When the total of the repeating unit (a) and the repeating unit (b) is 100 mol%, the repeating unit (a) is contained in an amount of 2 mol% or more and less than 95 mol%, and the repeating unit (b) is contained in an amount of 5 mol% or more. Contains less than 98 mol%. And when the total of repeating unit (a) and (b) is 100 mol%, 2-80 mol% of repeating units (a1) are contained.

  The polyfunctional vinyl aromatic copolymer has a number average molecular weight Mn of 300 to 100,000, a molecular weight distribution represented by a ratio of the weight average molecular weight Mw to the number average molecular weight of 100.0 or less, and toluene, xylene Soluble in tetrahydrofuran, dichloroethane or chloroform.

（式中、Ｒ^９はモノビニル芳香族化合物に由来する炭素数６〜３０の芳香族炭化水素基であり、Ｒ^１はジビニル芳香族化合物に由来する炭素数６〜３０の芳香族炭化水素基であり、ｊ及びｈは、その合計が２〜２０，０００であることを条件に、それぞれ独立に０〜２００の整数である。） Although it does not limit as a polyfunctional vinyl aromatic copolymer, For example, the repeating unit (a) derived from the divinyl aromatic compound shown by following formula (1), and the monovinyl shown by following formula (2) Examples thereof include a copolymer containing a structural unit derived from a repeating unit (b) derived from an aromatic compound. These structural units may be regularly arranged or randomly arranged.

(In the formula, R ⁹ is an aromatic hydrocarbon group having 6 to 30 carbon atoms derived from a monovinyl aromatic compound, and R ¹ is an aromatic hydrocarbon group having 6 to 30 carbon atoms derived from a divinyl aromatic compound. Yes, j and h are each independently an integer of 0 to 200, provided that the sum is 2 to 20,000.

As a suitable component (A), in the above formulas (1) and (2), R ¹ and R ⁹ may have a phenyl group which may have a substituent or a substituent. And a copolymer composed of a repeating unit which is an aromatic hydrocarbon group selected from the group consisting of a biphenyl group, an optionally substituted naphthalene group, and an optionally substituted terphenyl group. It is done.

  The polyfunctional vinyl aromatic copolymer as component (A) is characterized by being soluble in a solvent. In addition, the repeating unit referred to in the present specification is derived from a monomer, and is present in the main chain of the copolymer and repeatedly appears, and a unit or terminal group present in the terminal or side chain. including. A repeating unit is also called a structural unit. Moreover, the terminal group as used in this specification contains the terminal group derived from the below-mentioned chain transfer agent other than what originates in said monomer.

  The structural unit (a) derived from the divinyl aromatic compound is contained in an amount of 2 mol% or more and less than 95 mol% with respect to the total of the structural unit (b) derived from the divinyl aromatic compound and the monovinyl aromatic compound. The structural unit (a) derived from the divinyl aromatic compound can have a plurality of structures such as one in which two vinyl groups are reacted with each other, and the other in which two are reacted. It is preferable that the repeating unit in which only one vinyl group is reacted is included in an amount of 2 to 80 mol%, more preferably 5 to 70 mol%, still more preferably 10 to 60%, based on the total. Especially preferably, it is 15 to 50%. By setting it to 2 to 80 mol%, the dielectric loss tangent is low, the toughness is high, the heat resistance is excellent, and the compatibility with other resins is excellent. Moreover, when it is set as a resin composition, it is excellent in heat-and-moisture resistance, thermal stability, and moldability. If it is less than 2 mol%, the heat resistance tends to decrease, and if it exceeds 80 mol%, the interlaminar peel strength when it is made into a laminate tends to decrease.

  The polyfunctional vinyl aromatic copolymer contains 5 mol% or more and less than 98 mol% of the structural unit (b) derived from the monovinyl aromatic compound with respect to the above sum. Preferably it contains 10 mol% or more and less than 90 mol%. More preferably, it is 15 mol% or more and less than 85 mol%. If it is less than 5 mol%, the moldability is insufficient, and if it exceeds 98 mol%, the heat resistance of the cured product is insufficient.

  The vinyl group present in the above formula (a1) acts as a crosslinking component and contributes to the development of the heat resistance of the soluble polyfunctional vinyl aromatic copolymer. On the other hand, the structural unit (b) derived from the monovinyl aromatic compound does not have a vinyl group because it is considered that polymerization proceeds normally by a 1,2-addition reaction of a vinyl group. That is, the structural unit (b) derived from the monovinyl aromatic compound does not act as a crosslinking component, but contributes to exhibiting moldability.

As the monovinyl aromatic compound, styrene is preferably exemplified. Moreover, monovinyl aromatic compounds other than styrene can be used together with styrene.
In this case, when the total content of the structural unit (b1) derived from styrene and the structural unit (b2) derived from a monovinyl aromatic compound other than styrene is 100 mol%, the structural unit (b1 ) Content is preferably 99 to 20 mol%. More preferably, it is 98-30 mol%. If content of (b1) is the said range, since it has heat stability and a moldability, it is preferable. When the structural unit (b1) is larger than 99 mol%, the heat resistance tends to decrease, and when the structural unit (b2) is larger than 80 mol%, the moldability tends to decrease.

The number average molecular weight (number average molecular weight in terms of standard polystyrene measured using GPC) of the polyfunctional vinyl aromatic copolymer is preferably 300 to 100,000, more preferably 400 to 50,000, still more preferably. 500 to 10,000. When the Mn is less than 300, the amount of the monofunctional copolymer component contained in the polyfunctional vinyl aromatic copolymer increases, so that the heat resistance of the cured product tends to decrease. If it exceeds 000, a gel is likely to be formed, and the viscosity becomes high, so that the moldability tends to be lowered.
Moreover, the value of molecular weight distribution (Mw / Mn) represented by the ratio of weight average molecular weight (standard polystyrene equivalent weight average molecular weight measured using GPC) and Mn is 100.0 or less, preferably 50 0.0 or less, more preferably 1.5 to 30.0, and most preferably 2.0 to 20.0. When Mw / Mn exceeds 100.0, the processing characteristics of the polyfunctional vinyl aromatic copolymer tend to deteriorate and gel tends to be generated.

  The polyfunctional vinyl aromatic copolymer is soluble in toluene, xylene, tetrahydrofuran, dichloroethane or chloroform as a solvent, but is preferably soluble in any of the above solvents. In order to be a polyfunctional copolymer soluble in a solvent, it is necessary that a part of the vinyl group of divinylbenzene remains without being crosslinked and has an appropriate degree of crosslinking. Here, “soluble in a solvent” means that 5 g or more of the polyfunctional vinyl aromatic copolymer is dissolved in 100 g of the solvent, more preferably 30 g or more, particularly preferably 50 g or more. That is.

The divinyl aromatic compound plays a role of forming a branched structure to be multifunctional, and also serves as a crosslinking component for developing heat resistance when the obtained polyfunctional vinyl aromatic copolymer is thermally cured. Fulfill.
Examples of the divinyl aromatic compound include, but are not limited to, aromatics having two vinyl groups, divinylbenzene (including each positional isomer or a mixture thereof), divinylnaphthalene (each positional isomer or a mixture thereof) Divinylbiphenyl (including each positional isomer or a mixture thereof) is preferably used. Moreover, these can be used individually or in combination of 2 or more types. From the viewpoint of moldability, divinylbenzene (m-isomer, p-isomer, or a mixture of these positional isomers) is more preferable.

  Examples of monovinyl aromatic compounds include styrene and monovinyl aromatic compounds other than styrene. However, it is desirable that styrene is essential and a monovinyl aromatic compound other than styrene is used in combination.

Styrene as a monomer component plays a role in imparting low dielectric properties and thermal stability to a polyfunctional vinyl aromatic copolymer, and as a chain transfer agent, it controls the molecular weight of the polyfunctional vinyl aromatic copolymer. Fulfill.
In addition, monovinyl aromatic compounds other than styrene improve the solvent solubility and processability of the polyfunctional vinyl aromatic copolymer.

  Examples of monovinyl aromatic compounds other than styrene are not limited as long as they are aromatic other than styrene having one vinyl group, but vinyl aromatic compounds such as vinyl naphthalene and vinyl biphenyl; o-methylstyrene, m-methyl Nucleoalkyl-substituted vinyl aromatic compounds such as styrene, p-methylstyrene, o, p-dimethylstyrene, o-ethylvinylbenzene, m-ethylvinylbenzene, and p-ethylvinylbenzene; Preferably, ethyl vinyl benzene (respective isomers or these isomers are used because it prevents gelation of the polyfunctional vinyl aromatic copolymer, is highly effective in improving solvent solubility and processability, is low in cost, and is easily available. ), Ethyl vinyl biphenyl (including each positional isomer or a mixture thereof), or ethyl vinyl naphthalene (including each positional isomer or a mixture thereof). More preferred is ethylvinylbenzene (m-isomer, p-isomer or a mixture of these positional isomers) from the viewpoint of dielectric properties and cost.

  In addition to the divinyl aromatic compound and the monovinyl aromatic compound, other monomers such as a trivinyl aromatic compound, a trivinyl aliphatic compound, a divinyl aliphatic compound, a monovinyl aliphatic compound, and the like may be used without departing from the effects of the present invention. One or more components can be used, and the structural unit (c) derived therefrom can be introduced into the polyfunctional vinyl aromatic copolymer.

  Examples of the other monomer components include 1,3,5-trivinylbenzene, 1,3,5-trivinylnaphthalene, 1,2,4-trivinylcyclohexane, ethylene glycol diacrylate, butadiene, , 4-butanediol divinyl ether, cyclohexane dimethanol divinyl ether, diethylene glycol divinyl ether, triallyl isocyanurate and the like. These can be used alone or in combination of two or more.

  The other monomer component preferably has a mole fraction of less than 30 mol% with respect to the sum of all monomer components. That is, the repeating unit (c) derived from other monomer components has a molar fraction of 30 relative to the sum of the structural units (a), (b), and (c) derived from all monomer components constituting the copolymer. It is preferable that it is less than mol%.

The polyfunctional vinyl aromatic copolymer used as the component (A) is obtained by polymerizing a monomer containing a divinyl aromatic compound and a monovinyl aromatic compound in the presence of a Lewis acid catalyst.
As the Lewis acid catalyst used in the polymerization, any compound can be used without particular limitation as long as it is a compound comprising a metal ion (acid) and a ligand (base) and can accept an electron pair. Among Lewis acid catalysts, metal fluorides or complexes thereof are preferred from the viewpoint of the thermal decomposition resistance of the resulting copolymer, and in particular, B, Al, Ga, In, Si, Ge, Sn, Pb, Sb, Bi, Ti , W, Zn, Fe, V, etc., bivalent to hexavalent metal fluorides or complexes thereof are preferred. These catalysts can be used alone or in combination of two or more. From the viewpoint of controlling the molecular weight and molecular weight distribution of the resulting copolymer and polymerization activity, boron trifluoride ether complexes are most preferably used. Here, examples of the ether of the ether complex include diethyl ether and dimethyl ether. Furthermore, a known chain transfer agent (CTR) can be added for the purpose of controlling the molecular weight during polymerization. In this case, the chain transfer agent can control the molecular weight by capping the end of the growing polymer chain to stop the growth of the copolymer and suppress the increase in the molecular weight.

In addition, since the chain transfer agent chemically modifies the terminal of the copolymer, it also becomes a compound that plays a role of introducing a terminal group that enables functions such as toughness, low dielectric property, and adhesion. Examples of the compound having a function as a chain transfer agent include alcohol compounds such as t-butyl alcohol and cyclohexanol, phenol compounds, mercaptan compounds, carboxylic acid compounds, carboxylic acid anhydride compounds, 1-methoxynaphthalene and diphenyl ether. And ether compounds such as thioether compounds, t-butyl methacrylate, sec-butyl methacrylate, t-butyl acrylate, sec-butyl acrylate and the like, and thioester compounds. Of these, cyclohexanol and t-butyl methacrylate are preferred from the viewpoint of not impairing dielectric properties, and t-butyl methacrylate is more preferred from the viewpoint of easy reaction control. From the viewpoint of reactivity and moldability, aromatic ethers such as anisole, propoxybenzene, butoxybenzene, methoxynaphthalene, methoxybiphenyl, and biphenyl ether are preferable.
In addition to the above-mentioned compounds, monomers having low homopolymerizability can also be used as molecular weight regulators. Examples of such a monomer having low homopolymerization include a cycloolefin compound. Specific examples of the cycloolefin compound include monocyclic olefins such as cyclobutene, cyclopentene, and cyclooctene, as well as compounds having a norbornene ring structure such as norbornene and dicyclopentadiene (hereinafter referred to as norbornene compounds), indene. Examples thereof include cycloolefin compounds condensed with aromatic rings such as acenaphthylene, but are not limited to these compounds.
These chain transfer agents and molecular weight regulators are calculated as monomer components, and the structural units resulting therefrom are calculated as the structural units of the copolymer. These are calculated as the other monomer components.

In the curable resin composition of this invention, when the sum total of the said (A) component and (B) component and / or (C) component is 100 mass%, (A) component is 99-1 mass% containing. . Preferably, it contains 97-5 mass%. More preferably, (A) component is 95-10 mass%, More preferably, 90-15 mass% is contained.
When the blending amounts of the component (A), the component (B), and the component (C) are within the above ranges, a curable resin composition having an excellent balance between dielectric properties, adhesion, and heat resistance can be obtained.

  Moreover, the curable resin composition of this invention can mix | blend the thermoplastic resin as (B) component, the curable reactive resin as (C) component, or both.

  Next, the thermoplastic resin (B) will be described. The thermoplastic resin (B) is also referred to as component (B).

  Examples of the component (B) thermoplastic resin include polystyrene, polyphenylene ether resin, polyetherimide resin, polyether sulfone resin, PPS resin, polycyclopentadiene resin, polycycloolefin resin, and the like, and known thermoplastic elastomers. For example, styrene-ethylene-propylene copolymer, styrene-ethylene-butylene copolymer, styrene-butadiene copolymer, styrene-isoprene copolymer, hydrogenated styrene-butadiene copolymer, hydrogenated styrene-isoprene copolymer Examples thereof include polymers and the like, or rubbers such as polybutadiene and polyisoprene. Preferable examples include polyphenylene ether resin (unmodified) and hydrogenated styrene-butadiene copolymer.

  Next, the thermosetting crosslinking agent (C) will be described. A thermosetting crosslinking agent (C) is also called (C) component.

  As the thermosetting cross-linking agent as component (C), there are resins and compounds that give a cured resin by copolymerizing with a polyfunctional vinyl aromatic copolymer in addition to known thermosetting resins. For example, vinyl ester resin, polyvinyl benzyl resin, unsaturated polyester resin, curable vinyl resin, maleimide resin, epoxy resin, isocyanate resin, phenol resin, one type having one or more polymerizable unsaturated hydrocarbon groups in the molecule The above vinyl compounds etc. can be mentioned.

  Preferably, a polyvinyl benzyl resin, an epoxy resin, and one or more kinds of vinyl compounds having one or more polymerizable unsaturated hydrocarbon groups in the molecule are used. Particularly preferred are polyvinyl benzyl resins and one or more vinyl compounds having one or more polymerizable unsaturated hydrocarbon groups in the molecule.

When the thermosetting crosslinking agent of component (C) is an epoxy resin, it is preferably one or more epoxy resins selected from epoxy resins having two or more epoxy groups in one molecule. Examples of such epoxy resins include cresol novolac type epoxy resins, triphenylmethane type epoxy resins, biphenyl epoxy resins, naphthalene type epoxy resins, bisphenol A type epoxy resins and bisphenol F type epoxy resins. These may be used alone or in combination of two or more. In addition, although it is preferable not to contain a halogenated epoxy resin in the curable resin composition of this invention, as long as the effect of this invention is not impaired, you may mix | blend as needed.
By using such an epoxy resin, the influence on the excellent dielectric properties and fluidity of the curable resin composition of the present invention can be minimized, and the heat resistance and adhesion of the cured product can be sufficiently enhanced. it is conceivable that.

  When the thermosetting crosslinking agent of component (C) is one or more vinyl compounds having one or more polymerizable unsaturated hydrocarbon groups in the molecule (hereinafter also referred to as vinyl compounds), The type is not particularly limited. That is, the vinyl compounds only need to be capable of forming a crosslink and curing by reacting with the polyfunctional vinyl aromatic copolymer of the present invention. What a polymerizable unsaturated hydrocarbon group is a carbon-carbon unsaturated double bond is more preferable, and the compound which has two or more carbon-carbon unsaturated double bonds in a molecule | numerator is more preferable. In addition, (A) component is excluded from these vinyl compounds.

  The vinyl compounds preferably have a weight average molecular weight (Mw) of 100 to 5,000, more preferably 100 to 4,000, and still more preferably 100 to 3,000. There exists a possibility that it may become easy to volatilize from the compounding component system of curable resin composition as Mw is less than 100. Moreover, when Mw exceeds 5,000, there exists a possibility that the viscosity of the varnish of a curable resin composition and the melt viscosity at the time of heat molding may become high too much. Therefore, the curable resin composition excellent in the heat resistance of hardened | cured material is obtained as said Mw is in such a range. This is considered to be because a crosslink can be suitably formed by the reaction between the polyfunctional vinyl aromatic copolymer and the vinyl compounds. Here, Mw is a value measured using GPC.

  The average number of carbon-carbon unsaturated double bonds per molecule of vinyl compounds as a thermosetting crosslinking agent (the number of vinyl groups (including substituted vinyl groups), also referred to as the number of terminal double bonds). Although it varies depending on the Mw of the vinyl compounds, for example, 1 to 20 is preferable, and 2 to 18 is more preferable. When the number of terminal double bonds is too small, it is difficult to obtain a cured product having sufficient heat resistance. Further, when the number of terminal double bonds is too large, the reactivity becomes too high, for example, the storage stability of the curable resin composition is lowered, the fluidity of the curable resin composition is lowered, etc. There is a risk of malfunction.

  Examples of the vinyl compounds include trialkenyl isocyanurate compounds such as triallyl isocyanurate (TAIC), polyfunctional methacrylate compounds having two or more methacryl groups in the molecule, and polyfunctional acrylates having two or more acrylic groups in the molecule. Examples thereof include vinyl compounds having two or more vinyl groups in the molecule (polyfunctional vinyl compounds) such as compounds and polybutadiene, and vinylbenzyl compounds such as styrene and divinylbenzene having vinylbenzyl groups in the molecule. Among these, those having two or more carbon-carbon double bonds in the molecule are preferable. Specific examples include a trialkenyl isocyanurate compound, a polyfunctional acrylate compound, a polyfunctional methacrylate compound, a polyfunctional vinyl compound, and a divinylbenzene compound. When these are used, it is considered that crosslinking is more suitably formed by the curing reaction, and the heat resistance of the cured product of the curable resin composition can be further increased. Moreover, these may be used independently and may be used in combination of 2 or more type. Moreover, you may use together the compound which has one carbon-carbon unsaturated double bond in a molecule | numerator. Examples of the compound having one carbon-carbon unsaturated double bond in the molecule include a compound having one vinyl group in the molecule (monovinyl compound).

  The total blending amount of the component (B) and the component (C) is 1 to 90 parts by mass with respect to a total of 100 parts by mass of the component (A), the component (B), and the component (C). Preferably, it is 2-80 mass parts. It is particularly preferably 5 to 65 parts by mass.

A flame retardant can be mix | blended with the curable resin composition of this invention as (D) component. The flame retardancy of the cured product of the curable resin composition can be further enhanced by the flame retardant. Although a flame retardant is not specifically limited, A well-known flame retardant can be used.
Specifically, in the field where halogen-based flame retardants such as brominated flame retardants are used, for example, ethylenedipentabromobenzene, ethylenebistetrabromoimide, decabromodiphenyl oxide, and tetradecabromo having a melting point of 300 ° C. or higher. Diphenoxybenzene is preferred. By using a halogen-based flame retardant, it is considered that elimination of halogen at a high temperature can be suppressed and a decrease in heat resistance can be suppressed. In the field where halogen-free is required, phosphorus-based flame retardants such as phosphate ester-based flame retardants, phosphazene-based flame retardants, and phosphinate-based flame retardants can be used. Specific examples of the phosphate ester flame retardant include a condensed phosphate ester of dixylenyl phosphate. Specific examples of the phosphazene flame retardant include phenoxyphosphazene. Specific examples of the phosphinate flame retardant include a phosphinic acid metal salt of a dialkylphosphinic acid aluminum salt. Each illustrated flame retardant may be used independently and may be used in combination of 2 or more types.
The compounding amount of the flame retardant is such that the phosphorus atom content is 1.0 to 7.0 parts by mass with respect to 100 parts by mass in total of the components (A) to (C) and the flame retardant. Is preferably 1.5 to 5.5 parts by mass, and more preferably 1.8 to 4.8 parts by mass. In the case of a flame retardant other than phosphorus, it is preferably 5 to 50 parts by mass. If it is such content, it becomes the curable resin composition which was excellent by the heat resistance and flame retardance of hardened | cured material, maintaining the outstanding dielectric characteristic which the curable resin composition of this invention has. This is considered to be due to the fact that the flame retardancy can be sufficiently enhanced while sufficiently suppressing the decrease in dielectric properties and the heat resistance of the cured product due to the inclusion of the flame retardant.

In the curable resin composition of the present invention, a filler can be blended as the component (E). Examples of the filler include those added to improve the heat resistance and flame retardancy of the cured product of the curable resin composition, and known fillers can be used, but are not particularly limited. Moreover, heat resistance, dimensional stability, a flame retardance, etc. can further be improved by containing a filler. Specifically, silica such as spherical silica, metal oxide such as alumina, titanium oxide, and mica, metal hydroxide such as aluminum hydroxide and magnesium hydroxide, talc, aluminum borate, barium sulfate, and calcium carbonate Etc. Among these, silica, mica, and talc are preferable, and spherical silica is more preferable. Moreover, these 1 type may be used independently and may be used in combination of 2 or more type.
The filler may be used as it is, but may also be a surface treated with an epoxy silane type or amino silane type silane coupling agent. As the silane coupling agent, vinylsilane type, methacryloxysilane type, acryloxysilane type, and styrylsilane type silane coupling agents are preferable from the viewpoint of reactivity with the radical polymerization initiator. Thereby, the adhesive strength with metal foil and the interlayer adhesive strength between resin increase. In addition, the above silane coupling agent may be added by an integral blend method instead of using a surface treatment in advance on the filler.

  The content of the filler is preferably 10 to 200 parts by mass with respect to a total of 100 parts by mass of the solid content excluding the filler (including organic components such as monomers and flame retardant, excluding the solvent), It is preferable that it is 30-150 mass parts.

  The curable resin composition of the present invention may further contain additives other than those described above. Examples of additives include radical polymerization initiators (also referred to as radical polymerization catalysts), antifoaming agents such as silicone-based antifoaming agents and acrylic ester-based antifoaming agents, thermal stabilizers, antistatic agents, and ultraviolet absorbers. And dispersants such as dyes and pigments, lubricants, and wetting and dispersing agents.

  As the radical polymerization initiator of the present invention, for example, the curable resin composition of the present invention is cured by causing a crosslinking reaction by means of heating or the like, as will be described later. A radical polymerization initiator is contained for the purpose of accelerating the crosslinking reaction of the group.

  A known substance is used as the radical polymerization initiator. Representative examples include benzoyl peroxide, cumene hydroperoxide, 2,5-dimethylhexane-2,5-dihydroperoxide, 2,5-dimethyl-2,5-di (t-butylperoxy ) Hexin-3, di-t-butyl peroxide, t-butylcumyl peroxide, α, α′-bis (t-butylperoxy-m-isopropyl) benzene, 2,5-dimethyl-2,5-di (T-butylperoxy) hexane, dicumyl peroxide, di-t-butylperoxyisophthalate, t-butylperoxybenzoate, 2,2-bis (t-butylperoxy) butane, 2,2-bis (T-butylperoxy) octane, 2,5-dimethyl-2,5-di (benzoylperoxy) hexane, di (trimethylsilyl) par Although there are peroxides such as oxide and trimethylsilyltriphenylsilyl peroxide, they are not limited to these. Although not a peroxide, 2,3-dimethyl-2,3-diphenylbutane can also be used as a radical polymerization initiator. However, it is not limited to these examples. Among these, α, α '? Bis (t? Butylperoxy? M? Isopropyl) benzene is preferably used. α, α '? bis (t? butylperoxy? m? isopropyl) benzene has a relatively high reaction initiation temperature. For this reason, it is possible to suppress the acceleration of the curing reaction at the time when there is no need for curing such as when the prepreg is dried, and it is possible to suppress the decrease in the storage stability of the curable resin composition of the present invention. Furthermore, α, α '? Bis (t? Butylperoxy? M? Isopropyl) benzene has low volatility, and therefore does not volatilize during prepreg drying or storage, and has good stability. Moreover, a radical polymerization initiator may be used independently or may be used in combination of 2 or more type.

  The amount of the radical polymerization initiator is preferably in the range of 0.01 to 10 parts by weight, more preferably 0.1 to 8 parts by weight with respect to 100 parts by weight of the total of the component (A) and the component (C). It is a range. Within this range, the reaction proceeds satisfactorily without inhibiting the curing reaction.

The curable resin composition of the present invention is used for the purpose of impregnating a base material (fibrous base material) for forming a prepreg or a circuit board material for forming a circuit board when producing a prepreg. A resin varnish can be prepared by preparing it in a varnish form.
The resin varnish comprises a resin composition containing the components (A), (B) and / or (C) as essential components, and optionally containing components (D) to (E) and other additives. Obtained by dissolving or dispersing in a solvent. This resin varnish is suitable for circuit boards and can be used as a varnish for circuit board materials. In addition, the use of the circuit board material mentioned here specifically includes a printed wiring board, a printed circuit board, a flexible printed wiring board, a build-up wiring board, and the like.

The resin varnish is prepared, for example, as follows.
First, (A) component, (B) component and / or (C) component, and each component which can be melt | dissolved in organic solvents, such as curable reactive resin, are thrown into an organic solvent, and are dissolved. At this time, heating may be performed as necessary. Thereafter, if necessary, a component that does not dissolve in an organic solvent such as an inorganic filler is added, and dispersed using a ball mill, a bead mill, a planetary mixer, a roll mill, etc., so that a varnish-like curable resin composition is obtained. Is prepared. The organic solvent used here is not particularly limited as long as it can dissolve the component (A), the component (B), the component (C) and the like and does not inhibit the curing reaction. For example, ketones such as acetone, methyl ethyl ketone and methyl isobutyl ketone; esters such as ethyl acetate, propyl acetate and butyl acetate; polar solvents such as dimethylacetamide and dimethylformamide; aromatic hydrocarbon solvents such as toluene and xylene These may be used alone or in combination of two or more. From the viewpoint of dielectric properties, aromatic hydrocarbons such as benzene, toluene and xylene are preferred.

  When preparing the resin varnish, the amount of the organic solvent used is preferably 5 to 900% by weight, more preferably 10 to 700% by weight, particularly preferably 100% by weight of the curable resin composition of the present invention. Is 20 to 500% by weight. In addition, when the curable resin composition of the present invention is an organic solvent solution such as a resin varnish, the amount of the organic solvent is not included in the calculation of the composition.

  The cured product obtained by curing the curable resin composition of the present invention can be used as a molded product, a laminate, a cast product, an adhesive, a coating film, and a film. For example, the cured product of the semiconductor sealing material is a cast product or a molded product. As a method for obtaining a cured product for such use, a curable resin composition is cast, a transfer molding machine, an injection molding machine, or the like. The cured product can be obtained by molding at 80 to 230 ° C. for 0.5 to 10 hours. Moreover, the hardened | cured material of the varnish for circuit boards is a laminated body, and as a method of obtaining this hardened | cured material, the varnish for circuit boards is used for base materials, such as glass fiber, carbon fiber, polyester fiber, polyamide fiber, alumina fiber, and paper. It is impregnated and dried by heating to obtain a prepreg, which can be obtained alone or laminated with a metal foil such as a copper foil and subjected to hot press molding.

  By blending inorganic high dielectric powder such as barium titanate or inorganic magnetic substance such as ferrite into curable resin composition or resin varnish, it is more excellent as a material for electronic parts, especially as a high frequency electronic parts material. It becomes.

  The curable resin composition of the present invention can be used by laminating with a metal foil (meaning including a metal plate, the same shall apply hereinafter) as in the case of the cured composite material described later.

  Next, the curable composite material of the curable resin composition of the present invention and the cured product thereof will be described. A base material is added to the curable composite material of the curable resin composition of the present invention in order to increase mechanical strength and increase dimensional stability.

  As such a substrate, known materials are used. For example, various glass cloths such as roving cloth, cloth, chopped mat, and surfacing mat, asbestos cloth, metal fiber cloth, and other synthetic or natural inorganic fiber cloth. Woven fabrics or nonwoven fabrics obtained from liquid crystal fibers such as wholly aromatic polyamide fibers, wholly aromatic polyester fibers, polybenzozar fibers, woven fabrics or nonwoven fabrics obtained from synthetic fibers such as polyvinyl alcohol fibers, polyester fibers, acrylic fibers, Natural fiber cloth such as cotton cloth, linen cloth, felt, carbon fiber cloth, craft paper, cotton paper, cloth such as natural cellulosic cloth such as paper-glass mixed paper, paper, etc. each alone or in combination Used together.

The proportion of the base material is preferably 5 to 90 wt%, more preferably 10 to 80 wt%, and still more preferably 20 to 70 wt% in the curable composite material. When the base material is less than 5 wt%, the composite material is insufficient in dimensional stability and strength after curing, and when the base material is more than 90 wt%, the dielectric properties of the composite material are inferior.
In the curable composite material of the present invention, a coupling agent can be used for the purpose of improving the adhesiveness at the interface between the resin and the substrate, if necessary. As the coupling agent, general materials such as a silane coupling agent, a titanate coupling agent, an aluminum coupling agent, a zircoaluminate coupling agent can be used.

  As a method for producing the curable composite material of the present invention, for example, the curable resin composition of the present invention and, if necessary, other components in the above-mentioned aromatic or ketone solvent or a mixed solvent thereof. A method of uniformly dissolving or dispersing, impregnating the base material, and then drying is exemplified. Impregnation is performed by dipping or coating. Impregnation can be repeated multiple times as necessary. At this time, it is also possible to repeat the impregnation using a plurality of solutions having different compositions and concentrations, and finally adjust to the desired resin composition and resin amount. It is.

  The cured composite material is obtained by curing the curable composite material of the present invention by a method such as heating. The manufacturing method is not particularly limited. For example, a plurality of curable composite materials are stacked, and each layer is bonded under heat and pressure, and at the same time, thermosetting is performed to obtain a cured composite material having a desired thickness. it can. It is also possible to obtain a cured composite material having a new layer structure by combining a cured composite material once cured with adhesive and a curable composite material. Lamination molding and curing are usually performed simultaneously using a hot press or the like, but both may be performed independently. That is, the uncured or semi-cured composite material obtained by lamination molding in advance can be cured by heat treatment or another method.

  Curing or molding and curing of the curable resin composition or curable composite material of the present invention is preferably a temperature of 80 to 300 ° C., a pressure of 0.1 to 1000 kg / cm 2, a time of 1 minute to 10 hours, and more preferably. Can be carried out at a temperature of 150 to 250 ° C., a pressure of 1 to 500 kg / cm 2, and a time of 1 minute to 5 hours.

  The laminate of the present invention comprises a layer of the cured composite material of the present invention and a layer of metal foil. Examples of the metal foil used here include a copper foil and an aluminum foil. The thickness is not particularly limited, but is in the range of 3 to 200 μm, more preferably 3 to 105 μm.

  As a method for producing the laminate of the present invention, for example, the curable composite composition of the present invention described above and a curable composite material obtained from a base material, and a metal foil are laminated in a layer configuration according to the purpose, An example is a method in which the respective layers are bonded under heat and pressure, and at the same time, thermally cured. In the laminate of the curable resin composition of the present invention, the cured composite material and the metal foil are laminated in an arbitrary layer configuration. The metal foil can be used as a surface layer or an intermediate layer. In addition to the above, it is possible to make a multilayer by repeating lamination and curing a plurality of times.

  An adhesive can also be used for adhesion to the metal foil. Examples of the adhesive include, but are not limited to, epoxy, acrylic, phenol, and cyanoacrylate. The above lamination molding and curing can be performed under the same conditions as in the production of the cured composite material of the present invention.

By forming the curable resin composition of the present invention into a film, a film that is one form of the curable resin composition of the present invention can be obtained. Although the thickness is not specifically limited, Preferably it is 3-200 micrometers, More preferably, it is the range of 5-105 micrometers.
The method for producing the film of the present invention is not particularly limited. For example, the curable resin composition is uniformly dissolved or dispersed in an aromatic solvent, a ketone solvent or the like, or a mixed solvent thereof, to obtain a PET film. The method of drying after apply | coating to resin films, such as, etc. are mentioned. The application can be repeated multiple times as necessary. In this case, the application can be repeated using a plurality of solutions having different compositions and concentrations, and finally the desired resin composition and resin amount can be adjusted. It is.

  The metal foil with resin of the present invention is composed of the curable resin composition of the present invention and a metal foil. Examples of the metal foil used here include a copper foil and an aluminum foil. Although the thickness is not specifically limited, Preferably it is 3-200 micrometers, More preferably, it is the range of 5-105 micrometers.

  The method for producing the resin-coated metal foil of the present invention is not particularly limited. For example, the curable resin composition is uniformly dissolved or dispersed in an aromatic or ketone solvent or a mixed solvent thereof. The method of drying after apply | coating to metal foil is mentioned. The application can be repeated a plurality of times as necessary. At this time, the application can be repeated using a plurality of solutions having different compositions and concentrations, and finally adjusted to a desired resin composition and resin amount. Is possible.

  The polyfunctional vinyl aromatic copolymer of the present invention can be processed into a molding material, a sheet or a film, and has a low dielectric constant, a low water absorption, and a high heat resistance in the fields of the electric industry, the space / aircraft industry, the automobile, etc. It can be used for a low dielectric material, an insulating material, a heat-resistant material, a structural material, etc. that can satisfy the above characteristics. In particular, it can be used as a single-sided, double-sided, multilayer printed board, flexible printed board, build-up board or the like. Furthermore, semiconductor-related materials or optical materials, paints, photosensitive materials, adhesives, sewage treatment agents, heavy metal scavengers, ion exchange resins, antistatic agents, antioxidants, antifogging agents, rustproofing agents , Antifouling agent, disinfectant, insecticide, medical material, flocculant, surfactant, lubricant, solid fuel binder, conductive treatment agent, resin modifier, asphalt modifier plasticizer, sintered binder, etc. Can be applied.

  The curable resin composition of the present invention has a high dielectric property (low dielectric constant and low dielectric loss tangent) even after severe heat history, and has high adhesion reliability even in severe environments. In addition, the resin fluidity is excellent, the linear expansion is low, and the wiring embedding flatness is excellent. Therefore, in the fields of electrical / electronics industry, space / aircraft industry, etc., molding defects such as warping etc. corresponding to the miniaturization and thinning that have been strongly demanded in recent years as dielectric materials, insulating materials, heat resistant materials, structural materials, etc. A cured molded product having no phenomenon can be provided. Furthermore, it is possible to realize a curable resin composition, a cured product, or a material including the same that is excellent in reliability due to excellent wiring embedding flatness and adhesion between different materials.

EXAMPLES Next, although an Example demonstrates this invention, this invention is not limited by these. All parts in each example are parts by weight.
In addition, the physical-property measurement in the synthesis example of a polyfunctional vinyl aromatic copolymer was performed by the method shown below.

1) Molecular weight and molecular weight distribution of polymer GPC (manufactured by Tosoh Corporation, HLC-8120GPC) was used for molecular weight and molecular weight distribution measurement of polyfunctional vinyl aromatic copolymer, tetrahydrofuran as a solvent, flow rate 1.0 ml / min, column temperature 38. The measurement was carried out using a calibration curve of monodisperse polystyrene at ° C.

2) Polymer structure The polymer structure was measured by 13C-NMR and 1H-NMR analysis using a JNM-LA600 nuclear magnetic resonance spectrometer manufactured by JEOL. Chloroform-d1 was used as a solvent, and the resonance line of residual chloroform in chloroform-d1 was used as an internal standard. Furthermore, in addition to the 13C-NMR and 1H-NMR measurement results, the amount of specific structural units introduced was calculated from data on the total amount of each structural unit introduced into the copolymer obtained by GC analysis. The amount of pendant vinyl group units contained in the polyfunctional vinyl aromatic copolymer was calculated from the amount of the specific structural unit introduced into the number and the number average molecular weight obtained from the GPC measurement.

3) Glass transition temperature (Tg) of the cured product
The test piece used for the glass transition temperature (Tg) measurement was prepared according to the following method. That is, a varnish comprising 100 parts by weight of a cured resin composition, 0.5 parts by weight of a radical polymerization initiator, 0.2 parts by weight of a thermal stabilizer, and 100 parts by weight of toluene is placed on a mold under a vacuum press molding machine, The solvent was devolatilized under heating vacuum. Thereafter, an upper mold was placed, heated and pressed under vacuum, and held at 200 ° C. for 2 hours to form a flat plate having a thickness of 200 μm. A test piece having a width of 3.0 mm, a thickness of 200 μm, a length of 25 mm was prepared from the flat plate obtained by molding. The obtained test piece is set in a TMA (thermomechanical analyzer), heated to 220 ° C. at a temperature rising rate of 10 ° C./min in a nitrogen stream, and further heat-treated at 220 ° C. for 20 minutes to remain. The distortion was removed. After allowing the test piece to cool to room temperature, the test piece was fixed to a chuck of a TMA measuring apparatus, scan measurement was performed from 30 ° C. to 320 ° C. at a temperature rising rate of 10 ° C./min in a nitrogen stream, and Tg was determined by a tangential method.

6) Measurement of solvent solubility 100 g of polyfunctional vinyl aromatic copolymer is dissolved in 100 g of toluene, xylene, THF, dichloroethane, dichloromethane or chloroform. The case where it was not recognized was marked as ◯.

Synthesis example 1
Divinylbenzene 2.25 mol (292.9 g), ethyl vinylbenzene 1.32 mol (172.0 g), styrene 11.43 mol (1190.3 g), n-propyl acetate 15.0 mol (1532.0 g) The reactor was charged into a 5.0 L reactor, 600 mmol of boron trifluoride diethyl ether complex was added at 70 ° C., and the mixture was reacted for 4 hours. After the polymerization solution was stopped with an aqueous sodium hydrogen carbonate solution, the oil layer was washed three times with pure water and devolatilized at 60 ° C. to recover the copolymer. The obtained copolymer was weighed to confirm that 860.8 g of copolymer A-1 was obtained.

Mn of the obtained copolymer A-1 was 2,060, Mw was 30,700, and Mw / Mn was 14.9. By performing 13C-NMR and 1H-NMR analysis, resonance lines derived from the respective monomer units were observed in the copolymer A-1. Based on the NMR measurement result and the GC analysis result, the constituent unit of the copolymer A-1 was calculated as follows.
Structural unit (a) derived from divinylbenzene: 20.9 mol% (24.3 wt%)
Structural unit derived from ethyl vinyl benzene (b2): 9.1 mol% (10.7 wt%)
Structural unit derived from styrene (b1): 70.0 mol% (65.0 wt%)
Structural unit (a1) having a residual vinyl group derived from divinylbenzene: 16.7 mol% (18.5 wt%)

  A clear Tg of the cured product was not observed, and the softening temperature was 300 ° C. or higher. The weight loss at 350 ° C. was 2.11 wt%. The solvent solubility of copolymer A-1 was ○.

Synthesis example 2
3.0 mol (390.6 g) of divinylbenzene, 1.8 mol (229.4 g) of ethyl vinylbenzene, 10.2 mol (1066.3 g) of styrene, 15.0 mol (1532.0 g) of n-propyl acetate The reactor was charged into a 5.0 L reactor, 600 mmol of boron trifluoride diethyl ether complex was added at 70 ° C., and the mixture was reacted for 4 hours. After the polymerization solution was stopped with an aqueous sodium hydrogen carbonate solution, the oil layer was washed three times with pure water and devolatilized at 60 ° C. to recover the copolymer. The obtained copolymer was weighed to confirm that 896.7 g of copolymer A-2 was obtained.

Mn of the obtained copolymer A-2 was 2,980, Mw was 41,300, and Mw / Mn was 13.9. The structural unit of copolymer A-2 was calculated as follows.
Structural unit (a): 30.4 mol% (33.1 wt%)
Structural unit (b2): 12.2 mol% (14.2 wt%)
Structural unit (b1): 57.4 mol% (52.7 wt%)
Structural unit (a1): 23.9 mol% (25.9 wt%)
A clear Tg of the cured product was not observed, and the softening temperature was 300 ° C. or higher. The weight loss at 350 ° C. was 1.83 wt%. The solvent solubility of copolymer A-2 was ◯.

Synthesis example 3
1.28 mol (182.7 mL) of divinylbenzene (a mixture of 1,4-divinylbenzene and 1,3-divinylbenzene, and the following examples), ethylvinylbenzene (1-ethyl-4-vinylbenzene, and 1 -A mixture of ethyl-3-vinylbenzene, also in the following example) 0.97 mol (137.8 mL), t-butyl methacrylate 2.00 mol (323.2 mL), toluene 300 mL 2.0 L reactor Then, 50 mmol of boron trifluoride diethyl ether complex was added at 50 ° C. and reacted for 4 hours. After stopping the polymerization solution with an aqueous sodium hydrogen carbonate solution, the oil layer was washed 3 times with an aqueous sodium hydrogen carbonate solution, then 3 times with pure water, and devolatilized at 60 ° C. under reduced pressure to recover the polymer. The obtained polymer was weighed to confirm that 234.6 g of copolymer A-3 was obtained.

Mn of the obtained copolymer A-3 was 842, Mw was 3640, and Mw / Mn was 4.32. By performing 13C-NMR and 1H-NMR analyses, in the copolymer A-3, end group resonance lines derived from t-butyl methacrylate were observed. The amount (c1) of structural units derived from t-butyl methacrylate in the soluble polyfunctional vinyl aromatic polymer calculated from the elemental analysis results and the number average molecular weight in terms of standard polystyrene was 2.3 (pieces / molecule). It was. Further, 60.1 mol% of structural units derived from divinylbenzene and 39.9 mol% in total of structural units derived from ethyl vinylbenzene were contained (excluding terminal structural units). The vinyl group content contained in the copolymer A-3 was 36.2 mol% (excluding the terminal structural unit).
Moreover, clear Tg was not observed as a result of TMA measurement of hardened | cured material, and the softening temperature was 300 degreeC or more. As a result of TGA measurement, the weight loss at 350 ° C. was 2.80 wt%. The solvent solubility of copolymer C was ○.

Synthesis example 4
Divinylbenzene 0.63 mol (89.7 mL), Ethyl vinylbenzene 0.37 mol (52.7 mL), Norbornene 1.00 mol (94.2 g), Butyl acetate 0.40 mol (52.8 mL), Toluene 150 mL Was put in a 1.0 L reactor, 30 mmol of boron trifluoride diethyl ether complex was added at 70 ° C., and the mixture was reacted for 6 hours. After the polymerization solution was stopped with an aqueous sodium hydrogen carbonate solution, the oil layer was washed three times with pure water and devolatilized at 60 ° C. to recover the copolymer. The obtained copolymer was weighed to confirm that 117.8 g of copolymer A-4 was obtained.

Mn of the obtained copolymer A-4 was 2,500, Mw was 24,200, and Mw / Mn was 9.69. In the copolymer A-4, a resonance line derived from the end of norbornene was observed. The amount of the norbornene-derived terminal group (c1) introduced into the terminal of the polyfunctional vinyl aromatic copolymer was 2.6 (pieces / molecule). Further, it contained 54.1 wt% of structural units derived from divinylbenzene, 22.4 wt% in total of structural units derived from ethylvinylbenzene, and 23.5 wt% of structural units derived from norbornene (including terminal structural units). ). The content of structural units derived from divinylbenzene having residual vinyl groups contained in the copolymer D was 30.8 wt% (including terminal structural units).
Moreover, clear Tg of hardened | cured material was not observed and the softening temperature was 300 degreeC or more. As a result of TGA measurement, the weight loss at 350 ° C. was 2.20 wt%. The solvent solubility of copolymer A-4 was ○.

  Using the copolymers A-1 to A-4 obtained in Synthesis Examples 1 to 4, the properties of the cured products of the curable resin compositions using these copolymers were evaluated according to the following test methods. went.

9) Linear expansion coefficient and glass transition temperature The test piece used for the test of the linear expansion coefficient and the glass transition temperature was heated by placing a varnish of a curable resin composition on a flat plate mold under a vacuum press molding machine. The solvent was devolatilized under vacuum. Thereafter, an upper mold was placed with a 0.2 mm spacer in between, a heat press was performed under vacuum, and the plate was held at 200 ° C. for 1 hour to form a flat plate having a thickness of 0.2 mm. A test piece having a width of 3.0 mm, a thickness of 0.2 mm, a length of 40 mm is prepared from the flat plate obtained by molding, and is set only on the chuck above the TMA (thermomechanical analyzer). Under an air stream, the temperature was raised to 220 ° C. at a heating rate of 10 ° C./min, and the remaining solvent was removed by heat treatment at 220 ° C. for 20 minutes, and the molding distortion in the test piece was removed. After allowing the TMA to cool to room temperature, the lower part of the test piece in the TMA measuring device is also set on the probe for analysis, and scan measurement is performed from 30 ° C. to 360 ° C. at a heating rate of 10 ° C./min in a nitrogen stream. The linear expansion coefficient was calculated from the dimensional change at 0 to 40 ° C.
For the glass transition temperature Tg, the above test piece is set in a DMA (dynamic viscoelasticity device) measuring device and scanned from 30 ° C. to 320 ° C. at a temperature rising rate of 3 ° C./min in a nitrogen stream. The Tg was determined from the temperature at the peak top of the tan δ curve.

10) Dielectric constant and dielectric loss tangent In accordance with JIS C2565 standard, cured after storing for 24 hours in a room at 23 ° C and 50% humidity after dry-drying using a cavity resonator method dielectric constant measuring device manufactured by AET Co., Ltd. Using a flat plate test piece, the dielectric constant and dielectric loss tangent at 18 GHz were measured.

11) Copper foil peel strength A glass cloth (E glass, weight per unit area: 71 g / m 2) was immersed in a varnish of a thermosetting resin composition, impregnated, and dried in an air oven at 80 ° C. for 10 minutes. At that time, the resin content (RC) of the obtained prepreg was adjusted to 50 wt%.
Using this prepreg, a plurality of the above curable composite materials are stacked as necessary so that the thickness after molding becomes about 0.6 mm to 1.0 mm, and a copper foil having a thickness of 35 μm on both sides thereof (Product name: HS1-M2-VSP, copper foil, Rz: 1.2 μm) was placed and molded and cured by a vacuum press molding machine to obtain a laminate for evaluation. Curing conditions were a temperature rise of 3 ° C./min, a pressure of 3 MPa, and a temperature of 200 ° C. for 120 minutes to obtain a cured laminate as a copper clad laminate for evaluation.

A test piece having a width of 20 mm and a length of 100 mm was cut out from the cured laminate thus obtained, and a parallel cut having a width of 10 mm was made on the copper foil surface, and then 50 mm / 90 ° in the direction of 90 ° with respect to the surface. The copper foil was continuously peeled off at a speed of minutes, the stress at that time was measured with a tensile tester, and the minimum value of the stress was recorded as the copper foil peel strength. (Conforms to JIS C 6481).
The copper foil peel strength test after the wet heat resistance test was measured in the same manner as described above after the test piece was left at 85 ° C. and a relative humidity of 85% for 2 weeks.

12) Formability Using the copper clad laminate for evaluation formed in the previous section, the line width (L) is 0.5 mm and the line interval (S) is 0.5 mm (L / S = 0.5) in a lattice shape. /0.5 mm), a core material patterned was prepared. This core material was subjected to blackening treatment, and then a prepreg was further laminated thereon, followed by secondary molding, thereby producing an evaluation laminated substrate having an inner layer of a lattice pattern. About the created laminated substrate for evaluation, for example, it was confirmed whether defects such as voids due to insufficient fluidity of the resin varnish occurred. Thereafter, the laminated substrate for evaluation was immersed in boiling water for 4 hours, and then immersed in a solder bath at 290 ° C. At that time, the presence of voids could not be confirmed, and even after dipping in a solder bath, swelling, delamination, measling (white spots), etc. were not observed: ○, the failure occurred Or, the occurrence of the defective phenomenon was not observed, but the case where warpage occurred was evaluated as x.

Example 1
90 g of copolymer A-1 obtained in Synthesis Example 1, 10 g of thermoplastic resin B, 0.5 g of perbutyl P as a polymerization initiator, and 0.2 g of AO-60 as an antioxidant are dissolved in 100 g of toluene and cured. A resin composition (varnish A) was obtained.

  The prepared varnish A was dropped on the lower mold, the solvent was devolatilized at 135 ° C. under reduced pressure, the mold was assembled, and vacuum press was performed for 2 hours at 200 ° C. and 3 MPa, followed by thermosetting. I let you. About the obtained thickness: 0.2 mm hardened | cured material flat plate test piece, various characteristics including the dielectric constant of 18 GHz and a dielectric loss tangent were measured. Moreover, after leaving the hardened | cured material flat test piece to stand at 85 degreeC and 85% of relative humidity for 2 weeks, the dielectric constant and dielectric loss tangent were measured, and the dielectric constant and dielectric loss tangent after a heat-and-moisture resistance test were measured. The results obtained from these measurements are shown in Table 1. Furthermore, using this varnish, a prepreg, a test copper-clad laminate, and a laminate with test plating were prepared, and copper foil peel strength, copper plating peel strength, and formability were evaluated. It was. The test results are shown in Table 1.

Examples 2-3 and Comparative Examples 1-2
A curable resin composition (varnish) was obtained in the same manner as in Example 1 except that the formulation shown in Table 1 was used. Then, tests and evaluations were performed in the same manner as in Example 1. The results obtained by these tests are shown in Table 2. The varnish concentration (solid content concentration) was 50 wt%.

実施例４〜６、比較例３〜４
表２に示した配合処方としたこと以外は、実施例１と同様な方法で硬化性樹脂組成物（ワニス）を得た。そして、実施例１と同様にして、試験・評価を行った。これらの試験により得られた結果を表２に示した。なお、ワニス濃度（固形分濃度）は５０ｗｔ％とした。

Examples 4-6, Comparative Examples 3-4
A curable resin composition (varnish) was obtained in the same manner as in Example 1 except that the formulation shown in Table 2 was used. Then, tests and evaluations were performed in the same manner as in Example 1. The results obtained by these tests are shown in Table 2. The varnish concentration (solid content concentration) was 50 wt%.

In Tables 1 and 2, the components used are as follows.
Thermoplastic resin B-1: hydrogenated styrene butadiene block copolymer (manufactured by Kraton Polymers LLC, trade name: KRATON A1535)
Thermoplastic resin B-2: hydrogenated styrene butadiene block copolymer (manufactured by Kraton Polymers LLC, trade name: KRATON A1536)
Thermosetting crosslinking agent C: Tricyclodecane dimethanol dimethacrylate (manufactured by Kyoeisha Chemical Co., Ltd., trade name: DCP-M :)
Brominated flame retardant-A: ethylene bis (pentabromophenyl) ("SAYTEX 8010" manufactured by Albemarle Japan)
Spherical silica: manufactured by Admatechs, SE2050 SPE, average particle size 0.5 μm (treated with phenylsilane coupling agent)
Polymerization initiator-A: 1,3-bis (butylperoxyisopropyl) benzene (manufactured by NOF Corporation, perbutyl P)
Stabilizer-A: Tetrakis [methylene-3- (3 ′, 5′-di-t-butyl-4-hydroxyphenyl) propionate] methane (manufactured by ADEKA, ADK STAB AO-60)

  The cured product obtained by curing the curable resin composition of the present invention can be used as a molded product, a laminate, a cast product, an adhesive, a coating film, and a film, for example, for semiconductor sealing materials and electronic circuit formation. It can be used for copper foil.

Claims (10)

  The repeating unit derived from the divinyl aromatic compound (a) contains 2 mol% or more and less than 95 mol%, and the repeating unit derived from the monovinyl aromatic compound (b) is less than 98 mol%, 5 mol% or more. A curable resin composition containing a polyfunctional vinyl aromatic copolymer (A) and a thermoplastic resin (B) and / or a thermosetting cross-linking agent (C), which is a cured resin composition The dielectric loss tangent (Df) is 0.0025 or less, the peak temperature of the tan δ curve in the dynamic viscoelasticity measurement (DMA, tensile test method) is 200 ° C. or more, and the 90 ° peel strength to the copper foil is A curable resin composition characterized by being 0.5 kN / m or more.   The polyfunctional vinyl aromatic copolymer (A) contains an unsaturated hydrocarbon group derived from (a), has a number average molecular weight Mn of 300 to 100,000, and a molecular weight distribution (Mw / Mn). The curable resin composition according to claim 1, which is 100.0 or less and is soluble in toluene, xylene, tetrahydrofuran, dichloroethane or chloroform.   (D) A flame retardant and / or (E) a filler is contained, and the total content of (D) and (E) is 20 wt% or more and 95 wt% with respect to the entire thermosetting resin composition. The thermosetting resin composition according to claim 1 or 2, wherein:   Hardened | cured material formed by hardening | curing curable resin composition of any one of Claims 1-3.   The film which consists of curable resin composition of any one of Claims 1-3.   A curable composite material comprising the curable resin composition according to any one of claims 1 to 3 and a base material, wherein the base material is contained in a proportion of 5 to 90% by weight. Composite material.   A cured composite material obtained by curing the curable composite material according to claim 6.   A laminate comprising the cured composite material layer according to any one of claims 7 and a metal foil layer.   Metal foil with resin characterized by having the film | membrane of the curable resin composition of any one of Claims 1-3 on the single side | surface or both surfaces of metal foil.   The varnish for circuit board materials formed by dissolving the curable resin composition of any one of Claims 1-3 in the organic solvent.