Resin composition, and composite material set

Abstract

To provide a resin composition having a low dielectric loss tangent and excellent fluidity in the resin composition.SOLUTION: A resin composition according to the present invention contains an olefin-aromatic vinyl compound-aromatic polyene copolymer and a surface-treated silica powder, the surface-treated silica powder satisfying a (D90-D10) / D50 of 0.8-4.5, where D10 is the particle size at which the cumulative value from the small particle size side is 10%, D50 is the particle size at which the cumulative value is 50%, and D90 is the particle size at which the cumulative value is 90%, in the volume frequency particle size distribution of the powder as measured by a laser diffraction scattering method, and the moisture content generated from above 550°C and up to 900°C as measured by the Karl Fischer method is 500 ppm or less.SELECTED DRAWING: None

Description

[Technical Field]

[0001] The present invention relates to a resin composition and a composite material set. [Background technology]

[0002] Various developments have been made so far regarding resin compositions containing an olefin-polyene copolymer. For example, the technology described in Patent Document 1 is known as this type of technology. Patent Document 1 describes a post-curable resin composition containing an ethylene-olefin-polyene copolymer and an inorganic filler (paragraph 0032 of Patent Document 1, etc.). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2010-280771 Summary of the Invention [Problem to be solved by the invention]

[0004] However, as a result of investigations by the present inventors, it has been found that there is room for improvement in terms of low dielectric tangent and flowability of the resin composition containing an ethylene-olefin-polyene copolymer and an inorganic filler as described in Patent Document 1. [Means for solving the problem]

[0005] As a result of further investigations, the present inventors have found that in a resin composition comprising an olefin-aromatic vinyl compound-aromatic polyene copolymer and a surface-treated silica powder, the fluidity of the resin composition can be stably evaluated by using the moisture content of the surface silica powder as an index, and by using the dielectric loss tangent of the resin composition and the width of the particle size distribution of the surface silica powder as indexes; and that the dielectric loss tangent can be lowered by setting the upper limit of the moisture content to a predetermined value or less, and that the fluidity can be increased by setting the lower limit of the width of the particle size distribution to a predetermined value or more, thereby completing the present invention.

[0006] According to one aspect of the present invention, the following resin composition and composite material set are provided. 1. An olefin-aromatic vinyl compound-aromatic polyene copolymer; a surface-treated silica powder; The surface-treated silica powder is In the volume frequency particle size distribution of the powder measured by a laser diffraction scattering method, when the particle size at which the cumulative value from the small particle size side is 10% is D10, the particle size at which the cumulative value is 50%, and the particle size at which the cumulative value is 90% is D90, the ratio (D90-D10) / D50 satisfies 0.8 or more and 4.5 or less, and Measured by the Karl Fischer method, the amount of generated CO₂ is 500 ppm or less between 550°C and 900°C. Resin composition. 2. The resin composition according to 1., The specific surface area of ​​the surface-treated silica powder measured by the BET one-point method using nitrogen gas adsorption is 0.1 m 2 / g or more 12.0m 2 / g or less. 3. The resin composition according to 1. or 2., In the volume frequency particle size distribution of surface-treated silica powder measured by the laser diffraction scattering method, the particle size at which the cumulative value from the small particle size side reaches 50% is defined as D50. The resin composition, wherein the surface-treated silica powder has a D50 of 0.1 μm or more and 10 μm or less. 4. The resin composition according to any one of 1. to 3., The resin composition has a number average molecular weight Mn of 500 or more and 100,000 or less of the olefin-aromatic vinyl compound-aromatic polyene copolymer. 5. The resin composition according to any one of 1. to 4., The resin composition has a water absorption rate of 1.0% or less of the olefin-aromatic vinyl compound-aromatic polyene copolymer. 6. A composite material set comprising a combination of raw material components used to produce a resin composition containing an olefin-aromatic vinyl compound-aromatic polyene copolymer and silica powder, a resin varnish containing an olefin-aromatic vinyl compound-aromatic polyene copolymer and a solvent; a surface-treated silica powder; The surface-treated silica powder is In the volume frequency particle size distribution of the powder measured by a laser diffraction scattering method, when the particle size at which the cumulative value from the small particle size side is 10% is D10, the particle size at which the cumulative value is 50%, and the particle size at which the cumulative value is 90% is D90, the ratio (D90-D10) / D50 satisfies 0.8 or more and 4.5 or less, and The amount of moisture generated between 550℃ and 900℃, as measured by the Karl Fischer method, is 500 ppm or less. Composite materials set. [Effects of the Invention]

[0007] According to the present invention, there are provided a resin composition and a composite material set which have a low dielectric loss tangent and excellent flowability in the resin composition. DETAILED DESCRIPTION OF THE INVENTION

[0008] Hereinafter, embodiments of the present invention will be described with reference to the drawings. In all drawings, similar components are designated by similar reference numerals, and descriptions thereof will be omitted where appropriate. Furthermore, the drawings are schematic diagrams and do not correspond to actual dimensional proportions.

[0009] The resin composition of this embodiment will be outlined below.

[0010] The resin composition of the present embodiment contains an olefin-aromatic vinyl compound-aromatic polyene copolymer and a surface-treated silica powder. Surface-treated silica powder is In the volume frequency particle size distribution of the powder measured by a laser diffraction scattering method, when the particle size at which the cumulative value from the small particle size side is 10% is D10, the particle size at which the cumulative value is 50%, and the particle size at which the cumulative value is 90% is D90, the ratio (D90-D10) / D50 satisfies 0.8 or more and 4.5 or less, and The amount of moisture generated between 550°C and 900°C, as measured by the Karl Fischer method, is configured to be 500 ppm or less.

[0011] Furthermore, in this embodiment, a composite material set can be provided that includes a combination of raw material components used to produce a resin composition containing an olefin-aromatic vinyl compound-aromatic polyene copolymer and silica powder. The composite material set includes a resin varnish containing an olefin-aromatic vinyl compound-aromatic polyene copolymer and a solvent, and the surface-treated silica powder described above.

[0012] Each component of the resin composition of this embodiment will be described in detail below.

[0013] <Olefin-aromatic vinyl compound-aromatic polyene copolymer> The olefin-aromatic vinyl compound-aromatic polyene copolymer (hereinafter sometimes simply referred to as "copolymer") is a copolymer comprising a structural unit A derived from an olefin monomer, a structural unit B derived from an aromatic vinyl compound monomer, and a structural unit C derived from an aromatic polyene monomer, and preferably satisfies all of the following conditions (1) to (4):

[0014] (1) The number average molecular weight of the copolymer is 500 or more and 100,000 or less. (2) The aromatic vinyl compound monomer is an aromatic vinyl compound having 8 to 20 carbon atoms, and the content of the aromatic vinyl compound monomer unit in the copolymer is 0 to 70% by mass. (3) The aromatic polyene is one or more selected from polyenes having 5 to 20 carbon atoms and having a plurality of vinyl groups and / or vinylene groups in the molecule, and the content of vinyl groups and / or vinylene groups derived from aromatic polyene units in the copolymer is 1.5 or more and less than 20 per number average molecular weight. (4) The olefin is one or more olefins selected from olefins having 2 to 20 carbon atoms, and the total amount of the olefin monomer units, aromatic vinyl compound monomer units, and aromatic polyene monomer units in the copolymer is 100 mass%.

[0015] The structural unit A can improve the low dielectric property and flexibility of the copolymer. The structural unit B can improve the low dielectric property of the copolymer and the compatibility with other materials. The structural unit C can improve the low dielectric properties and crosslinkability of the copolymer. That is, a hydrocarbon-based copolymer having the above structural units A, B, and C becomes a crosslinkable low dielectric resin, preferably a crosslinkable soft low dielectric resin. Generally, when a soft resin such as polybutadiene is used, the crosslinkability can be increased, but the dielectric loss tangent tends to decrease. In contrast, in this embodiment, by including the structural units A, B, and C, it is possible to realize a copolymer that is a soft resin with crosslinkability and yet has low dielectric properties. A resin composition containing such a copolymer can realize a high frequency resin material with reduced signal transmission loss in the high frequency range. Furthermore, the following advantages can be obtained from the properties derived from the structural units of the copolymer. The compatibility of the copolymer increases the solubility in solvents, allowing the resin composition to be used in the form of a resin varnish with excellent processability.The compatibility of the copolymer also increases the compatibility with other resins, such as hard resins, allowing the resin composition to be used as a composite material containing other resins. The crosslinking property of the copolymer makes it possible to realize a high frequency resin material having relatively high heat resistance.

[0016] The olefin monomer does not include unsaturated hydrocarbons having aromatic groups, but is, for example, one or more selected from α-olefins having from 2 to 20 carbon atoms and cyclic olefins having from 5 to 20 carbon atoms. These compounds are composed of carbon and hydrogen and contain substantially no oxygen, nitrogen, or halogens. Examples of α-olefins having from 2 to 20 carbon atoms include ethylene, propylene, 1-butene, 1-hexene, 1-octene, 1-decane, 1-dodecane, 4-methyl-1-pentene, and 3,5,5-trimethyl-1-hexene. Examples of cyclic olefins having from 5 to 20 carbon atoms include norbornene and cyclopentene. Preferred olefins are a combination of ethylene and an α-olefin other than ethylene or a cyclic olefin, or ethylene alone. Ethylene alone, or a mass ratio of the α-olefin other than ethylene to ethylene of 1 / 7 or less, more preferably 1 / 10 or less, is preferred, as it increases the peel strength of the resulting cured product with copper foil or copper wiring. More preferably, the content of α-olefin monomer units other than ethylene in the copolymer is 6% by mass or less, most preferably 4% by mass or less, or the olefin is ethylene alone. In this case, the peel strength with copper foil or copper wiring can be further increased, which is more preferable. Furthermore, with the preferred combination of ethylene and an α-olefin other than ethylene, the glass transition temperature of the ethylene-α-olefin-aromatic vinyl compound-aromatic polyene sequence of the finally obtained cured product can be freely adjusted within the range of approximately -60°C to -10°C depending on the type and content of the α-olefin.

[0017] The aromatic vinyl compound monomer is an aromatic vinyl compound having 8 to 20 carbon atoms, and examples thereof include styrene, paramethylstyrene, paraisobutylstyrene, various vinylnaphthalenes, and various vinylanthracenes.

[0018] The aromatic polyene monomer is a polyene having 5 to 20 carbon atoms and containing multiple vinyl and / or vinylene groups (preferably vinyl groups) in its molecule, preferably a polyene having 8 to 20 carbon atoms. The aromatic polyene monomer is preferably a polyene having 8 to 20 carbon atoms and containing multiple vinyl groups in its molecule, more preferably various ortho-, meta-, and para-divinylbenzenes or mixtures thereof, divinylnaphthalene, divinylanthracene, p-2-propenylstyrene, and p-3-butenylstyrene, which have an aromatic vinyl structure and are substantially free of oxygen, nitrogen, and halogens and are composed of carbon and hydrogen. Also usable are bifunctional aromatic vinyl compounds such as 1,2-bis(vinylphenyl)ethane (abbreviation: BVPE), as described in JP 2004-087639 A. Among these, various ortho-, meta-, and para-divinylbenzenes or mixtures thereof are preferred, and a mixture of meta- and para-divinylbenzene is most preferred. In this specification, these divinylbenzenes are referred to as "divinylbenzenes." When divinylbenzenes are used as aromatic polyenes, they are preferred because they have high curing efficiency and are easy to cure when subjected to a curing treatment.

[0019] Each of the olefin, aromatic vinyl compound, and aromatic polyene monomers may independently contain another polar group, for example, an olefin containing an oxygen atom, a nitrogen atom, or the like, an aromatic vinyl compound containing an oxygen atom, a nitrogen atom, or the like, or an aromatic polyene containing an oxygen atom, a nitrogen atom, or the like. The total mass of these polar group-containing monomers is preferably 10 mass% or less, more preferably 3 mass% or less, of the total mass of the composition, and most preferably no polar group-containing monomers are included. By keeping the amount of such monomers at 10 mass% or less, the low dielectric properties (low dielectric constant / low dielectric loss) of the cured product obtained by curing the composition can be improved.

[0020] The number average molecular weight of the copolymer is 500 or more and 100,000 or less, preferably 5,000 or more and 100,000 or less, more preferably 20,000 or more and 100,000 or less, and even more preferably 30,000 or more and 100,000 or less. By setting the molecular weight within the above range, the composition becomes less sticky in the uncured state even when other resins described below are added, and the thermoplasticity can be improved.Furthermore, the final cured product can be easily imparted with good physical properties such as high strength at break and high elongation at break.If the number average molecular weight is less than 500, the mechanical properties of the composition in the uncured state are low and the adhesiveness is high, which may make it difficult to mold the composition as a thermoplastic resin.If the number average molecular weight is more than 100,000, the moldability may be reduced.

[0021] In this specification, the number average molecular weight is determined as follows. The molecular weight can be determined by GPC (gel permeation chromatography) as the number average molecular weight (Mn) converted to standard polystyrene. Measurement can be carried out under the following conditions. Column: Four TSKgel GMHXL φ7.8×300 mm (manufactured by Tosoh Corporation) connected in series. Column temperature: 40℃ Solvent: THF Flow rate: 1.0 ml / min. Detector: RI detector

[0022] The content of aromatic vinyl compound monomer units in the copolymer is 0% by mass or more and 70% by mass or less, preferably 0% by mass or more and less than 70% by mass, more preferably 10% by mass or more and 60% by mass or less, and even more preferably 10% by mass or more and 55% by mass or less. If the content of aromatic vinyl compound monomer units is greater than 70% by mass, the glass transition temperature of the final cured product of the composition will be near room temperature, which may result in reduced toughness and elongation at low temperatures. If the content of aromatic vinyl compound monomer units is 10% by mass or more, the aromaticity of the copolymer is improved, improving compatibility with flame retardants and fillers, preventing bleed-out of flame retardants and allowing filler incorporation. Furthermore, if the content of aromatic vinyl compound monomer units is 10% by mass or more, a cured product of the composition will have high peel strength with copper foil or copper wiring.

[0023] In the copolymer, the content of vinyl groups and / or vinylene groups derived from aromatic polyene units per number average molecular weight is 1.5 or more and less than 20, preferably 1.5 or more and less than 7, and more preferably 2 or more and less than 5. The content of vinyl groups and / or vinylene groups is hereinafter sometimes collectively referred to as the "vinyl group content." If the vinyl group content is less than 1.5, the crosslinking efficiency is low, making it difficult to obtain a cured product with sufficient crosslink density. Increasing the vinyl group content makes it easier to improve the mechanical properties of the final cured product at room temperature and high temperatures.

[0024] The vinyl group content derived from aromatic polyene units (divinylbenzene units) per number average molecular weight in the copolymer is determined by the number average molecular weight (Mn) calculated in terms of standard polystyrene obtained by a GPC (gel permeation chromatography) method known to those skilled in the art, and 1 This can be obtained by comparing the vinyl group content and vinylene group content derived from aromatic polyene units obtained by H-NMR measurement. For example, 1By comparing the intensity of each peak area obtained by H-NMR measurement, if the content of vinyl groups derived from aromatic polyene units (divinylbenzene units) in the copolymer is 0.095% by mass, and the number average molecular weight converted to standard polystyrene by GPC measurement is 68,000, the molecular weight of vinyl groups derived from aromatic polyene units in the number average molecular weight is the product of these, 64.8, which when divided by the formula weight of the vinyl groups, 27, becomes 2.4. In other words, the content of vinyl groups derived from aromatic polyene units per number average molecular weight in this copolymer is 2.4. 1 The assignment of peaks obtained by H-NMR measurement is known from literature. 1 A method for determining the copolymer composition from a comparison of peak areas obtained by H-NMR measurement is also known. 13 The peak area or ratio of the C-NMR spectrum may be used. In this specification, the content of divinylbenzene units in a copolymer is determined by the peak intensity ( 1 This is determined from the content of vinyl groups derived from divinylbenzene units (measured by H-NMR). In other words, the content of divinylbenzene units is determined from the content of vinyl groups derived from divinylbenzene units, assuming that one vinyl group is derived from one divinylbenzene unit in the copolymer.

[0025] In the copolymer, the olefin monomer unit content is preferably 30% by mass or more, and particularly preferably 45% by mass or more. The total of the olefin monomer units, aromatic vinyl compound monomer units, and aromatic polyene monomer units is 100% by mass. When the olefin monomer unit content is 30% by mass or more, the toughness (elongation) of the final cured body is improved, and cracking during curing, a decrease in the impact resistance of the cured body, and cracking during heat cycle testing of the cured body do not occur. In this copolymer, the olefin monomer unit content is preferably 90% by mass or less.

[0026] In the copolymer, specific examples of suitable olefin-aromatic polyene copolymers that do not contain aromatic vinyl compound monomer units include ethylene-divinylbenzene copolymer, ethylene-propylene-divinylbenzene copolymer, ethylene-1-butene-divinylbenzene copolymer, ethylene-1-hexene-divinylbenzene copolymer, and ethylene-1-octene-divinylbenzene copolymer.

[0027] In the copolymer, examples of the olefin-aromatic vinyl compound-aromatic polyene copolymer containing an aromatic vinyl compound monomer unit include an ethylene-styrene-divinylbenzene copolymer, an ethylene-propylene-styrene-divinylbenzene copolymer, an ethylene-1-hexene-styrene-divinylbenzene copolymer, and an ethylene-1-octene-styrene-divinylbenzene copolymer.

[0028] The upper limit of the water absorption rate of the copolymer is, for example, 1.0% or less, preferably 0.5% or less, and more preferably 0.1% or less. The lower limit of the water absorption rate of the copolymer is not particularly limited, but may be equal to or higher than the measurement limit. The water absorption rate of the copolymer is determined by immersing the copolymer in water at 25°C in the atmosphere for 24 hours and measuring the change in weight before and after immersion.

[0029] The copolymer can be produced by the production methods described in, for example, WO 00 / 37517, JP 2009-161743 A, JP 2010-280771 A, JP 2009-161743 A, JP 2010-280771 A, and the like.

[0030] <Surface-treated silica powder>

[0031] The upper limit of the amount of moisture generated in the surface silica powder before the temperature reaches from over 550°C to 900°C as measured by the Karl Fischer method is 500 ppm or less, preferably 400 ppm or less, and more preferably 300 ppm or less, thereby reducing the dielectric loss tangent of the resin composition. On the other hand, the lower limit of the amount of water generated between 550°C and 900°C is not particularly limited, but may be 0 ppm or more, or 1 ppm or more.

[0032] The water content in the powder can be measured by the following Karl Fischer method. Specifically, a trace moisture measuring device (Mitsubishi Chemical Corporation, Model CA-05) was used. The powder was placed in a quartz tube in a moisture vaporization mechanism, and heated from room temperature to 900°C using an electric heater while dehydrated argon gas was supplied as a carrier gas. The water vapor volatilized from the powder surface was introduced into the moisture measurement mechanism, where the moisture content was measured.

[0033] In the volume frequency particle size distribution of the surface-treated silica powder measured by the laser diffraction scattering method, the particle size at which the cumulative value from the small particle size side reaches 10% is defined as D10, the particle size at which the cumulative value reaches 50%, and the particle size at which the cumulative value reaches 90% is defined as D90.

[0034] The lower limit of (D90-D10) / D50 is 0.8 or more, preferably 0.9 or more, and more preferably 1.0 or more, which can improve the fluidity of the resin composition. The upper limit of (D90-D10) / D50 is, for example, 4.5 or less, preferably 4.0 or less, and more preferably 3.5 or less, which can further reduce the dielectric loss tangent of the resin composition.

[0035] The lower limit of D50 is, for example, 0.1 μm or more, preferably 0.2 μm or more, and more preferably 0.3 μm or more, which can improve the fillability into the resin. The upper limit of D50 is, for example, 10 μm or less, preferably 9 μm or less, and more preferably 8 μm or less, which can reduce the amount of coarse particles and make it possible to further reduce the sheet thickness when the resin composition is molded into a sheet.

[0036] The lower limit of the specific surface area (S) of the surface-treated silica powder measured by the BET one-point method using nitrogen gas adsorption is, for example, 0.1 m 2 / g or more, preferably 0.3m 2 / g or more, more preferably 0.5m 2 This allows the amount of the polysiloxane added to the resin to be increased, and the thermal expansion coefficient of the resin composition to be suppressed. The upper limit of the specific surface area (S) of the surface-treated silica powder is, for example, 12.0 m 2 / g or less, preferably 8.5m 2 / g or less, more preferably 7.0m 2 / g or less, which can suppress the aggregation of the filler.

[0037] The BET single-point method using nitrogen gas adsorption can be performed using a specific surface area measuring device (for example, Yuasa Ionics, device name: MONOSORB) using nitrogen gas as the adsorption gas and helium gas as the carrier gas, and can be performed after drying and degassing 1 g of sample at 300°C for 15 minutes.

[0038] The lower limit of the average sphericity of the surface-treated silica powder is, for example, 0.80 or more, preferably 0.85 or more, and more preferably 0.90 or more, which can further improve the flowability of the resin composition. The upper limit of the average sphericity of the surface-treated silica powder is not particularly limited, but may be, for example, 1.00 or less.

[0039] In this embodiment, for example, by appropriately selecting the adjusting method of raw silica powder or the surface treatment method of raw silica powder, etc., it is possible to control the moisture content.Among these, for example, the elements that can make the moisture content within desired numerical range are appropriately adjusting the specific surface area of ​​raw silica powder, adjusting the amount of silane coupling agent added per specific surface area according to the type of silane coupling agent, and carrying out heat treatment before silane coupling treatment. Furthermore, the particle size distribution of the surface-treated silica powder, such as (D90-D10) / D50, can be controlled by classification using a sieve or a classifier such as a precision air classifier.

[0040] The surface-treated silica powder may be any powder containing silica (SiO2) as a main component. The term "main component" means that the silica powder contains, for example, 50% or more, preferably 80% or more, and more preferably 90% or more, of silica (SiO2) in terms of mass, based on the total amount of the silica powder.

[0041] The surface-treated silica powder includes either or both of amorphous and crystalline silica.

[0042] The surface-treated silica powder preferably has an amorphous fraction of 95% or more, more preferably 97% or more, as measured by the following method. The amorphous fraction is determined by X-ray diffraction analysis using a powder X-ray diffractometer (e.g., Rigaku Corporation, Model MiniFlex) in the 2θ range of 26° to 27.5° with CuKα radiation, and the intensity ratio of specific diffraction peaks is used to determine the amorphous fraction. In the case of siliceous powder, crystalline silica exhibits a main peak at 26.7°, while amorphous silica exhibits no peak. When amorphous and crystalline silica are mixed, a peak height at 26.7° corresponding to the proportion of crystalline silica is obtained. Therefore, the crystalline silica mixing ratio (X-ray diffraction intensity of sample / X-ray diffraction intensity of crystalline silica) is calculated from the ratio of the X-ray intensity of the sample to that of a crystalline silica standard sample, and the amorphous fraction is then calculated using the formula: amorphous fraction (%) = (1 - crystalline silica mixing ratio) × 100.

[0043] The silane coupling agent may contain a silane compound having one or more functional groups selected from the group consisting of, for example, an epoxy group, a methacryl group, an acrylic group, an amino group, a vinyl group, an alkyl group, a phenyl group, a mercapto group, a styryl group, an acid anhydride group, a ureido group, an isocyanurate group, and an isocyanate group, preferably an epoxy group, a methacryl group, an acrylic group, an amino group, a vinyl group, an alkyl group, and a phenyl group.

[0044] The silane compound has one or more hydrolyzable groups in addition to functional groups in the molecule. As the hydrolyzable group, for example, an alkoxy group such as a methoxy group or an ethoxy group is used. The alkoxy groups are hydrolyzed to generate silanol groups, which chemically react with OH groups (reactive sites) present on the surface of the silica particles, thereby chemically bonding the silane coupling agent to the surface of the silica particles. The surface-treated silica powder has a silane coupling agent chemically and / or physically bonded to the surface of the silica particles.

[0045] Examples of silane compounds having an epoxy group include 3-glycidoxypropyltrimethoxysilane, 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, 3-glycidoxypropylmethyldimethoxysilane, 3-glycidoxypropylmethyldiethoxysilane, and 3-glycidoxypropyltriethoxysilane. Examples of silane compounds having a methacryl group include 3-methacryloxypropyltrimethoxysilane, 8-methacryloxyoctyltrimethoxysilane, 3-methacryloxypropylmethyldimethoxysilane, 3-methacryloxypropylmethyldiethoxysilane, and 3-methacryloxypropyltriethoxysilane. Examples of silane compounds having an acrylic group include 3-acryloxypropyltrimethoxysilane. Examples of silane compounds having an amino group include N-phenyl-3-aminopropyltrimethoxysilane, 3-aminopropyltrimethoxysilane, N-2-(aminoethyl)-3-aminopropylmethyldimethoxysilane, N-2-(aminoethyl)-3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, 3-triethoxysilyl-N-(1,3-dimethyl-butylidene)propylamine, N-phenyl-3-aminopropyltrimethoxysilane, and N-(vinylbenzyl)-2-aminoethyl-3-aminopropyltrimethoxysilane hydrochloride. Examples of silane compounds having a vinyl group include vinyltrimethoxysilane, 7-octenyltrimethoxysilane, and vinyltriethoxysilane. Examples of silane compounds having an alkyl group include hexyltrimethoxysilane, octyltriethoxysilane, and decyltrimethoxysilane. Examples of silane compounds having a phenyl group include phenyltrimethoxysilane and trimethoxy(2-phenylethyl)silane.

[0046] The content of the surface-treated silica powder is, for example, 1 to 90 mass %, preferably 10 to 80 mass %, more preferably 20 to 70 mass %, relative to 100 mass % of the total content of the surface-treated silica powder and the copolymer.

[0047] Next, a method for producing the surface-treated silica powder will be described.

[0048] An example of a method for producing the surface-treated silica powder is as follows: heat-treating the prepared silica powder; The method includes a step of bringing the heat-treated silica powder into contact with a silane coupling agent to carry out a silane coupling treatment in which the silane coupling agent reacts with the surfaces of the silica particles, thereby obtaining a surface-treated silica powder. According to this embodiment, a surface-treated silica powder with excellent low dielectric properties can be realized by two-stage surface treatment, namely, heat treatment and silane coupling treatment.

[0049] In one example of preparing the silica powder in this embodiment, raw silica powder produced by a dry method is subjected to coarse powder classification and then to fine powder classification, thereby obtaining the silica powder. In addition, classification can be performed by mixing or classifying appropriate amounts of silica powders having different particle size compositions. Industrially, classification using a classifier such as a sieve or a precision air classifier is desirable, and the classification operation is preferably a dry method. By dry classifying raw silica powder produced by a dry method, aggregation of the silica powder can be suppressed compared to raw silica powder produced by a wet method and / or wet classification, and handling properties can be improved. The obtained silica powder is preferably stored in a moisture-proof bag.

[0050] The raw silica powder can be produced by any method, such as by introducing crushed powder of silica stone, silica sand, quartz, etc. into a flame or high-temperature plasma and spheroidizing it; by synthesizing and spheroidizing it by gas-phase hydrolysis of silicon tetrachloride and using this as a raw material and subjecting it to calcination or flame spraying treatment; or by synthesizing and spheroidizing it in the gas or liquid phase using metallic silicon or alkoxysilane as a starting material and subjecting it to further calcination or flame spraying treatment and spheroidizing it.

[0051] The prepared silica powder is subjected to a heat treatment under the following conditions. The heat treatment is carried out in a hot air or electric furnace at a temperature of 500 to 1100°C for a predetermined time (e.g., about 1 to 52 hours) such that the heating temperature (°C) x heating time (h) is 1000 to 26400 (°C·h), preferably 1800 to 17600 (°C·h) for a predetermined time (e.g., about 2 to 35 hours). If the heating temperature is 500 to 1100°C, the specific surface area and average particle size do not change before and after heating. Therefore, it is desirable to carry out the classification step before heating, and then adjust the specific surface area and average particle size to the desired values ​​before carrying out the heat treatment. After the heat treatment, the powder is left to cool naturally in the electric furnace, and the silica powder is recovered at 110°C to 300°C. It is then further cooled to 25°C in an environment with a humidity of 40% RH or less, and stored at 15 to 25°C. It may also be recovered and stored in a moisture-proof aluminum bag.

[0052] The heat-treated silica powder is subjected to a silane coupling treatment using a silane coupling agent. As a method for surface treatment with a silane coupling agent, well-known techniques such as a dry method or a wet method can be used, but it is preferable to use a dry method. The dry method is not particularly limited as long as it is a method of contacting a silane coupling agent with spherical silica powder in a solid state, and any known method can be used, including, for example, a stirring method that applies shear force, a mixing method using a ball mill, a mixer, etc. Here, the solid state refers to a state in which the raw silica powder is not dispersed in a dispersion medium. During the treatment with the silane coupling agent, an acidic substance or an alkaline substance may be present.

[0053] The silane coupling agent treatment is carried out, for example, by adding a silane coupling agent to the heat-treated silica powder under atmospheric pressure, at a temperature of 0 to 120°C, and at a humidity of 10 to 90%, and mixing them for 10 minutes to 10 hours using the above-mentioned mixing method. If necessary, after mixing, the mixture may be allowed to stand for 0 to 10 days under the same environmental conditions. Thereafter, if necessary, the silica powder treated with the coupling agent may be further subjected to a drying treatment at 100 to 300° C. for 1 to 10 hours.

[0054] <Resins other than copolymers> The resin composition of the present embodiment may contain other resins in addition to the copolymer described above, as necessary, as long as the effects of the present invention are not impaired. The other resins may preferably be one or more selected from hydrocarbon elastomers, polyphenylene ethers, and aromatic polyene resins. Among these, polyphenylene ethers or hydrocarbon elastomers are more preferred. Among hydrocarbon elastomers, conjugated diene polymers are preferred. Among conjugated diene polymers, 1,2-polybutadiene is preferred. The use of one or more resins selected from hydrocarbon elastomers, polyphenylene ethers, and aromatic polyene resins has the effect of reducing the amount of monomer used, and for example, making it possible to obtain a suitable cured product of the present invention without using any monomer. The amount of other resins may be preferably 1 to 500 parts by mass, more preferably 1 to 300 parts by mass, in total, per 100 parts by mass of the copolymer.

[0055] <Curing agent> The resin composition of the present embodiment may contain a curing agent for the copolymer and / or other resins as needed, as long as the effects of the present invention are not impaired. As the curing agent, a known curing agent that can be used for the polymerization or curing of conventional aromatic polyenes or aromatic vinyl compounds may be used. Examples of such curing agents include radical polymerization initiators, cationic polymerization initiators, and anionic polymerization initiators, but radical polymerization initiators are preferred. Organic peroxides, azo polymerization initiators, etc. are preferred, and can be freely selected depending on the application and conditions. Also, known photopolymerization initiators that use light, ultraviolet light, or radiation can be used as curing agents. Examples of curing agents that use photopolymerization initiators include photoradical polymerization initiators, photocationic polymerization initiators, and photoanionic polymerization initiators. Such photopolymerization initiators are available, for example, from Tokyo Chemical Industry Co., Ltd. Furthermore, curing can also be achieved by radiation or electron beams themselves. Furthermore, crosslinking and curing can also be achieved by thermal polymerization of the raw materials contained therein without using a curing agent. There are no particular restrictions on the amount of curing agent used, but generally, 0.01 to 10 parts by mass per 100 parts by mass of the composition (preferably excluding the curing agent and solvent) is preferred. When using a curing agent such as a peroxide or azo-based polymerization initiator, the curing process should be carried out at an appropriate temperature and time, taking into account its half-life. In this case, the conditions can be determined according to the curing agent, but a temperature range of approximately 50°C to 180°C is generally appropriate.

[0056] <Monomer> The resin composition of this embodiment may contain a monomer, if necessary, as long as it does not impair the effects of the present invention. The amount of the monomer is optional, but is preferably 300 parts by mass or less per 100 parts by mass of the copolymer. The composition may be substantially free of a monomer. If a monomer is contained, the amount is preferably 1 part by mass or more, more preferably 5 parts by mass or more. When the amount of the monomer is 300 parts by mass or less, the uncured composition does not become viscous, making it easy to mold and process as a thermoplastic resin. Furthermore, when the content of the volatile monomer is below a certain level, odor in the uncured state is not a problem. When a solvent is added to the composition to produce a varnish-like product, the monomer is lost as the solvent evaporates during use, which can lead to a problem of a decrease in the effective content of the monomer. Furthermore, when the product is in the form of an uncured sheet, containing a certain amount of monomer or less reduces the change in the monomer content during storage. Monomers suitable for use in the composition of the present invention preferably have a molecular weight of less than 1,000, more preferably less than 500. Monomers that can be suitably used in the composition of the present invention are aromatic vinyl compound monomers, aromatic polyene monomers, and / or polar monomers. The monomers are preferably those that can be polymerized with a radical polymerization initiator, and more preferably one or more of the group consisting of aromatic vinyl compounds and aromatic polyenes. Also suitable for use is BVPE (1,2-bis(vinylphenyl)ethane), as described in JP-A-2003-212941.

[0057] The amounts of the monomers used can be exemplified as follows: From the viewpoint of increasing the mechanical strength (elastic modulus) of the cured product at high temperatures, the amount of aromatic vinyl compound is preferably 50 parts by mass or more and 250 parts by mass or less, and more preferably 80 parts by mass or more and 200 parts by mass or less, per 100 parts by mass of the copolymer. From the viewpoint of increasing the mechanical strength (elastic modulus) of the cured product at high temperatures, the amount of aromatic polyene is preferably 1 part by mass or more and 30 parts by mass or less, per 100 parts by mass of the copolymer. When an aromatic vinyl compound and an aromatic polyene are used, the mass ratio of the aromatic vinyl compound to the aromatic polyene is preferably 70 to 99:1 to 30, and more preferably 85 to 95:5 to 15, per 100 parts by mass of the total of the aromatic vinyl compound and the aromatic polyene.

[0058] Preferably, a relatively small amount of polar monomer can be used to impart adhesion to other materials required as an insulating material or to impart or adjust the mechanical properties of the cured product. Examples of the polar monomer include various maleimides, bismaleimides, maleic anhydride, glycidyl (meth)acrylate, triallyl isocyanurate, tri(meth)acrylic isocyanurate, and trimethylolpropane tri(meth)acrylate. Maleimides and bismaleimides that can be used in the present invention are described, for example, in International Publication No. 2016 / 114287 and Japanese Patent Application Laid-Open No. 2008-291227, and are available commercially from Daiwa Chemical Industry Co., Ltd. and Designer Molecules Inc. These maleimide group-containing compounds may be used as polyaminobismaleimide compounds from the viewpoints of solubility in organic solvents, high-frequency characteristics, high adhesion to conductors, and prepreg moldability. Polyaminobismaleimide compounds can be obtained, for example, by subjecting a compound having two maleimide groups at its terminals to a Michael addition reaction with an aromatic diamine compound having two primary amino groups in the molecule. To achieve high crosslinking efficiency with a small amount of addition, polar monomers having bifunctional or higher polyfunctional groups are preferred, such as bismaleimides, triallyl isocyanurate (TAIC), and trimethylolpropane tri(meth)acrylate. The amount of polar monomer that may be contained in the composition may be in the range of 0.1 to 30 parts by mass, preferably 0.1 to 10 parts by mass, per 100 parts by mass of the copolymer. Using 30 parts by mass or less results in low dielectric constants and dielectric loss tangents for the resulting cured product.

[0059] <Solvent> The resin composition of the present embodiment may contain a solvent as needed. The solvent is used to adjust the viscosity and fluidity of the composition. Volatile solvents are preferred, such as cyclohexane, toluene, ethylbenzene, acetone, and isopropanol. The amount used is preferably 10 parts by mass or less per 100 parts by mass of the copolymer of the present invention. From the viewpoint of moldability and handling of the composition as a thermoplastic resin before curing, and from the viewpoint of removal during and after curing, it is more preferable to use substantially no solvent. "Substantially no solvent" preferably means 5 parts by mass or less, more preferably 1 part by mass or less, and most preferably 0 parts by mass. Particularly when used as a varnish, it is preferable to add an appropriate solvent to the composition of the present invention. The solvent is used to adjust the viscosity and fluidity of the composition as a varnish. A solvent with a high boiling point at atmospheric pressure, i.e., low volatility, results in a uniform thickness of the applied film; therefore, a solvent with a boiling point above a certain level is preferred. A preferred boiling point is 100°C or higher at atmospheric pressure, more preferably 110°C or higher and 300°C or lower. Solvents suitable for such varnishes include cyclohexane, toluene, xylene, mesitylene, tetralin, acetone, ethylbenzene, limonene, mixed alkanes, mixed aromatic solvents, ethylene glycol methyl ether acetate, ethylene glycol monoethyl ether acetate, ethylene glycol monobutyl ether, etc. The amount used is preferably in the range of 10 to 2000 parts by mass, more preferably 5 to 500 parts by mass, and even more preferably 10 to 300 parts by mass, per 100 parts by mass of the composition of the present invention.

[0060] <Other additives> The resin composition of the present embodiment may contain additives other than the above-mentioned components as needed, as long as the effects of the present invention are not impaired. Other additives may include fillers other than the surface-treated silica powder, antioxidants, weathering agents, light stabilizers, lubricants, compatibilizers, antistatic agents, flame retardants, surface modifiers, heat stabilizers, ultraviolet absorbers, antiaging agents, lubricants, colorants, pigments, and the like. These may be contained alone or in any combination of two or more.

[0061] The other fillers include known inorganic or organic fillers other than the surface-treated silica powder. When adding an inorganic filler, it is particularly preferable to use a known surface modifier, such as a silane coupling agent. The type and amount of the other filler can be appropriately selected depending on the purpose. From the viewpoint of low dielectric loss tangent, examples of inorganic fillers include boron nitride (BN), etc. Examples of organic fillers include high molecular weight polyethylene and ultra-high molecular weight polyethylene, etc.

[0062] The resin composition of this embodiment can be in the form of a product such as a "thermoplastic composition," a "semi-cured state (such as a B-stage sheet)," or a "varnish" by appropriately adjusting the blending ratio of the copolymer, the surface-treated silica powder, and these, and, if necessary, the blending ratio of other resins, monomers, solvents, other additives, etc.

[0063] <Thermoplastic composition and molded article> The resin composition of this embodiment uses a copolymer having a molecular weight above a certain range, and when it also contains the specified other resin, it can exhibit the properties of a thermoplastic resin. Therefore, it can be molded into shapes such as sheets, tubes, strips, pellets, etc. in a substantially uncured state by a known molding method for thermoplastic resins under conditions that do not cause crosslinking. The molded product may then be crosslinked (cured). A preferred embodiment of the present composition is as follows. When the composition contains a certain proportion or more of one or more resins selected from the hydrocarbon elastomer, polyphenylene ether, olefin-aromatic vinyl compound-aromatic polyene copolymer oligomer, or aromatic polyene resin as other resins, excluding resins that are liquid at room temperature, the composition can be easily molded as a thermoplastic resin in an uncured state. Specifically, the hydrocarbon elastomer (excluding liquid resins) and / or polyphenylene ether can be added in an amount of 30 to 200 parts by mass per 100 parts by mass of the copolymer. Furthermore, when the other resins are liquid at room temperature, they can be added in an amount of preferably 1 to 30 parts by mass, and particularly preferably 1 to 20 parts by mass, per 100 parts by mass of the copolymer. The amount of the monomer used in the present thermoplastic composition may be preferably 10 parts by mass or less per 100 parts by mass of the copolymer. The number-average molecular weight of the copolymer used is 500 to 100,000, preferably 20,000 to 100,000, and more preferably 30,000 to 100,000. The thermoplastic composition described above may be molded into various shapes such as a sheet in advance by utilizing its thermoplasticity at a temperature below the action temperature of the curing agent, and may be combined with a semiconductor element, wiring, or substrate and laminated therewith, as necessary, and then heated to cure and bond. In a preferred embodiment, the thermoplastic composition of the present invention containing the surface-treated silica is molded into a molded product (either an uncured or semi-cured molded product) in advance, which has the advantage of making it easier to suppress increases in the dielectric constant and dielectric loss tangent associated with water absorption (water adsorption) of the silica. Such molded products are preferably in the form of sheets or pellets. Such molded products are also useful as masterbatches, and in particular, pellet-shaped products are suitable as masterbatches when adding the surface-treated silica to other materials. The composition of the present invention may be provided as a sheet formed by a known method from a composition heated and melted at a temperature below the curing agent's working temperature or decomposition temperature. Forming into a sheet may be accomplished by T-die extrusion, two-roll extrusion, or extrusion lamination onto a substrate film. In this case, the composition's composition, copolymer / monomer mass ratio, or solvent, other resin, or flame retardant is selected and adjusted so that the composition melts below the curing agent's working temperature or decomposition temperature and solidifies near room temperature. In this case, the sheet is substantially uncured. After various processing and assembly steps, the sheet is finally treated at a temperature and time above the curing agent's working temperature or decomposition temperature to achieve complete curing. This method is a common technique used for ethylene-vinyl acetate resin-based crosslinked sealant sheets for solar cells (photovoltaic power generation devices).

[0064] <Molded body in semi-cured state (B-stage sheet, etc.)> The composition of the present invention can also be formed into a molded article, such as a sheet or tube, in a partially crosslinked state, e.g., a semi-cured state (so-called B-stage state) by reacting a portion of the curing agent contained therein. For example, by using multiple curing agents and / or curing conditions with different curing temperatures, the composition can be semi-cured and the melt viscosity and fluidity can be controlled to achieve a B-stage state. That is, the curable resin or composition can be molded into an easily handled B-stage sheet by a first curing step (partial curing), which can then be laminated and pressure-bonded to an electronic device or substrate, followed by a second curing step (complete curing) to form the final shape. In this case, the composition composition, i.e., the copolymer / monomer mass ratio, can be selected, and if necessary, a solvent, other resins, and flame retardants can be added. The composition, which further contains a curing agent such as peroxide, can be partially cured to form a sheet (B-stage state), which can then be molded and assembled into a device, and then heated under pressure to fully cure. Known methods can be used to partially cure the composition. For example, one method involves using a combination of peroxides with different decomposition temperatures, treating for a predetermined period of time at a temperature at which only one of the peroxides is substantially active, obtaining a semi-hardened sheet, and finally treating for a sufficient period of time at a temperature at which all of the hardeners are active to completely harden the sheet. Furthermore, the molded article may be a sheet. The sheet may be uncured (semi-cured) to the extent that it can maintain its sheet shape, or may be fully cured. The degree of curing of the composition can be quantitatively measured by known dynamic mechanical analysis (DMA).

[0065] <Varnish-like composition and molded article thereof> The composition of the present invention can also be made into a viscous liquid varnish by adjusting its composition and blending ratio. For example, a varnish can be obtained by using a sufficient amount of solvent and / or an appropriate amount of liquid monomer. When used as a varnish, it is preferable to add an appropriate solvent to the composition of the present invention. The solvent is used to adjust the viscosity and fluidity of the composition as a varnish. A solvent with a high boiling point at atmospheric pressure, i.e., low volatility, contributes to a uniform thickness of the applied film; therefore, a solvent with a boiling point above a certain level is preferred. A preferred boiling point is approximately 110°C to 300°C at atmospheric pressure. Examples of solvents suitable for such varnishes include toluene, xylene, mesitylene, ethylbenzene, limonene, ethylene glycol methyl ether acetate, ethylene glycol monoethyl ether acetate, and ethylene glycol monobutyl ether. The amount of the solvent used is preferably in the range of 10 to 2,000 parts by mass per 100 parts by mass of the composition of the present invention. The varnish can be applied to or impregnated into a substrate, and the solvent can be removed by drying or other methods to produce an uncured or semi-cured molded product. This molded product generally has the form of a sheet, film, or tape. The resulting uncured or semi-cured molded product can then be cured under specified conditions, such as by heating or pressing.

[0066] <Curing> The composition can be cured by a known method, taking into consideration the curing conditions (temperature, time, pressure) of the curing agent contained therein. When the curing agent used is a peroxide, the curing conditions can be determined by taking into consideration the half-life temperature and the like disclosed for each peroxide. <Cured product of the composition>

[0067] <General uses of the composition> The composition of the present invention can be used as a substrate or board, such as a single-layer or multilayer printed circuit board, a flexible printed circuit board, a so-called single-layer or multilayer CCL (copper clad laminate), or a single-layer or multilayer FCCL (flexible copper clad laminate) board. It can also be used as various insulating materials for wiring, preferably for high-frequency signal wiring, such as coverlays, solder resists, build-up materials, interlayer insulating agents, bonding sheets, interlayer adhesives, and bump sheets for flip-chip bonders.

[0068] <Use of the composition as an uncured or partially cured sheet> Uncured or partially cured sheets of the composition of the present invention can be suitably used as high-frequency electrical insulating materials. For example, they can be used as build-up films, bonding sheets, coverlay sheets, bump sheets for flip-chip bonders, or insulating or adhesive layers for substrates. The composition of the present invention can be used as a replacement for conventionally used epoxy resin or silicone resin sheets. The composition of the present invention can form a cured insulating layer or cured matrix phase with a low dielectric constant and low dielectric loss by undergoing a curing treatment. The sheet generally has a thickness of 1 to 300 μm. The sheet may contain woven or nonwoven fabrics such as glass cloth or ceramic fibers. The sheet may be impregnated or may be multilayered with these. Furthermore, flexible, bendable wiring insulated partially or completely by the sheet can be used as an antenna cable for mobile phones and the like, replacing conventional coaxial cables. For example, the sheet of the present invention or a B-stage sheet (coverlay sheet) can be used to cover wiring using a substrate of LCP (liquid crystal polymer), PPE sheet, fluorine-based resin, or polyimide resin, followed by curing and adhering to the substrate, and used as an insulating material. Multilayer wiring boards in which the cured product obtained using the composition of the present invention serves as an insulating layer can be wiring boards with low dielectric loss and excellent high-frequency characteristics. In this case, in addition to low dielectric loss, advantages include heat resistance sufficient to withstand soldering, and a certain degree of flexibility, elongation, and impact resistance sufficient to withstand stress due to heat cycles or differential thermal expansion. For example, wiring boards can be produced by laminating and pressing a core material, such as glass or quartz cloth, nonwoven fabric, film material, ceramic substrate, glass substrate, general-purpose resin plate (e.g., epoxy), or general-purpose laminate, with an insulating layer-attached conductor foil made of the cured product. Alternatively, an insulating layer can be formed by applying a slurry or solution containing the present composition to the core material, drying, and curing. The thickness of the insulating layer is generally 1 to 300 μm. Such multilayer wiring boards can also be used in a multilayered or integrated configuration. The cured product obtained by curing the varnish-like composition of the present invention, in particular, can be suitably used as an electrical insulating material, as described above, and in particular can be used as a potting material, surface coating agent, coverlay, solder resist, buildup material, underfill material, filling insulating agent, interlayer insulating agent, or interlayer adhesive, or as a cured product for printed circuit boards, flexible printed circuit boards, CCL (copper clad laminate) substrates, FCCL (flexible copper clad laminate) substrates, or as a buildup film, bonding sheet, coverlay sheet, or cured product of a bump sheet for a flip chip bonder, as an electrical insulating material, in particular an electrical insulating material for high frequencies. In another aspect, the present invention provides a polymer composition comprising an olefin-aromatic vinyl compound-aromatic polyene copolymer, the polymer composition having a storage modulus of 10 MPa or more and 10 GPa or less at 250°C, a dielectric constant of 2.0 or more and 3.5 or less at 23°C, 10 GHz or 25 GHz to 40 GHz, and a dielectric loss tangent of 1.2 × 10 -3 There can be provided an electrically insulating material that is: The uncured or semi-cured thermoplastic composition of the present invention can be bonded to metal foil, particularly copper foil for wiring, by heat and pressure treatment without the need for adhesive coating or adhesive treatment to obtain a laminate. Here, the term "metal foil" includes metal wiring. In particular, when the olefin-aromatic vinyl compound-aromatic polyene copolymer is used, preferably a copolymer containing 10% by mass or more of aromatic vinyl compound, and / or when the olefin is ethylene alone or the mass ratio of olefin monomer components other than ethylene to the ethylene monomer component contained in the olefin is 1 / 7 or less, a peel strength of 1 N / mm or more can be obtained as measured in accordance with Japanese Industrial Standards (JIS) C6481:1996. More preferably, the copolymer can achieve a peel strength of 1.3 N / mm or more. More preferably, the copolymer can achieve a peel strength of 1.3 N / mm or more when the olefin is ethylene alone or the ratio of olefin monomer components other than ethylene to the ethylene monomer component is 1 / 10 or less, and most preferably when the copolymer contains 4% or less of α-olefin monomer units other than ethylene. It is generally known that adhesive treatments deteriorate the dielectric properties of laminates such as copper-clad laminate sheets. Therefore, even without such treatments, it is preferable to provide a peel strength of 1 N / mm or more as measured according to Japanese Industrial Standards (JIS) C6481:1996. Thus, the uncured or semi-cured thermoplastic composition of the present invention can be bonded to metal foils, such as copper foils for wiring, by curing treatments such as heat and pressure treatments, without the need for adhesive coating or adhesive treatment. However, this invention does not preclude the use of other adhesive-imparting measures (such as adhesive coating or adhesive treatments) to impart adhesion to metal foils or other components, including the addition of the aforementioned "surface modifier." It is also possible to obtain a cured product by curing the above-mentioned laminate. The composition of the present invention, for example, the curable composition, has the properties of a thermoplastic resin. Furthermore, the cured product obtained by curing the curable composition has excellent low dielectric properties, a high storage modulus at high temperatures, and a small coefficient of thermal expansion (CTE), making it particularly suitable for use in various electronic substrates.

[0069] Although the embodiments of the present invention have been described above, these are merely examples of the present invention, and various other configurations may be adopted. Furthermore, the present invention is not limited to the above-described embodiments, and modifications and improvements within the scope of achieving the object of the present invention are included in the present invention. [Example]

[0070] The present invention will be described in detail below with reference to examples, but the present invention is not limited to the descriptions of these examples.

[0071] <Production of Olefin-Aromatic Vinyl Compound-Aromatic Polyene Copolymer> With reference to the production methods described in Japanese Patent Laid-Open Nos. 9-40709 and 9-309925, polymerization was carried out using dimethylmethylenebiscyclopentadienylzirconium dichloride as a catalyst, triisobutylaluminum (TIBAL hexane solution, manufactured by Tosoh Finechem Corporation) as a cocatalyst, and styrene, divinylbenzene, and ethylene as raw materials, to obtain an olefin-aromatic vinyl compound-aromatic polyene copolymer (hereinafter referred to as copolymer P1). When the total of the olefin monomer units, the aromatic vinyl compound monomer units, and the aromatic polyene monomer units was 100% by mass, the composition of copolymer P1 was such that the ethylene content was 78% by mass, the 1-hexene content was 0% by mass, the styrene content was 20% by mass, and the divinylbenzene content was 2% by mass. The number average molecular weight Mn of the copolymer P1 was 7,500. The water absorption rate in copolymer P1 was less than 0.1%.

[0072] The divinylbenzene used was divinylbenzene (meta-para mixed product, divinylbenzene purity 81%) manufactured by Nippon Steel Chemical & Material Co., Ltd. The curing agent used was Perbutyl P (1,4-bis[(t-butylperoxy)isopropyl]benzene) manufactured by NOF Corporation or Percumyl D (dicumyl peroxide) manufactured by NOF Corporation.

[0073] The content of vinyl group units derived from ethylene, hexene, styrene, and divinylbenzene in an olefin-aromatic vinyl compound-aromatic polyene copolymer is determined by: 1 The H-NMR was performed based on the peak area intensity assigned to each. The sample was dissolved in deuterated 1,1,2,2-tetrachloroethane, and the measurement was carried out at 80 to 130°C. The molecular weight was determined as a number average molecular weight (Mn) converted to standard polystyrene using GPC (gel permeation chromatography) under the following conditions. Column: Four TSKgel GMHXL φ7.8×300 mm (manufactured by Tosoh Corporation) connected in series. Column temperature: 40℃ Solvent: THF Flow rate: 1.0 ml / min. Detector: RI detector

[0074] <Production of surface-treated silica powder> (Surface-treated silica powder 1) A silica powder having the particle size distribution shown in Table 1 was prepared. The prepared silica powder was placed in an alumina crucible and heat-treated in an electric furnace at 1000°C for 4 hours in the atmosphere. After the heat treatment, the mixture was cooled to 200°C in the furnace and then to room temperature in a desiccator (23°C, 10% RH), and the heat-treated silica powder was collected. 0.4 parts by mass of vinylsilane (KBM-1003 manufactured by Shin-Etsu Silicones Co., Ltd.) was added to 100 parts by mass of the heat-treated silica powder, and the mixture was mixed for 30 minutes using a vibration mixer (manufactured by Resodyn), followed by drying at 120°C for 4 hours to obtain surface-treated silica powder 1.

[0075] (Surface-treated silica powder 2-5) Surface-treated silica powder 2 was obtained in the same manner as surface-treated silica powder 1, except that silica powder having the particle size distribution shown in Table 1 was used and 0.4 parts by mass of methacrylsilane (KBM-503 manufactured by Shin-Etsu Silicones Co., Ltd.) was added instead of vinylsilane per 100 parts by mass of the heat-treated silica powder. Surface-treated silica powder 3 was obtained in the same manner as surface-treated silica powder 1, except that silica powder having the particle size distribution shown in Table 1 was used and 0.3 parts by mass of vinylsilane was added to 100 parts by mass of the heat-treated silica powder. Surface-treated silica powder 4 was obtained in the same manner as surface-treated silica powder 1, except that silica powder having the particle size distribution shown in Table 1 was used and 0.1 parts by mass of vinylsilane was added to 100 parts by mass of the heat-treated silica powder. Surface-treated silica powder 5 was obtained in the same manner as surface-treated silica powder 1, except that silica powder having the particle size distribution shown in Table 1 was used and 0.4 parts by mass of phenylsilane (KBM-103 manufactured by Shin-Etsu Silicones Co., Ltd.) was added instead of vinylsilane per 100 parts by mass of the heat-treated silica powder.

[0076] (Surface-treated silica powder 6) Silica powder having the particle size distribution shown in Table 1 was used, and without heat treatment, 1.1 parts by mass of vinylsilane (manufactured by Shin-Etsu Silicones Co., Ltd.) was added to 100 parts by mass of the prepared silica powder, and the mixture was mixed for 30 minutes in a vibration mixer (manufactured by Resodyn), followed by drying at 120°C for 4 hours to obtain surface-treated silica powder 6.

[0077] (Surface-treated silica powder 7) Surface-treated silica powder 7 was obtained in the same manner as surface-treated silica powder 1, except that silica powder having the particle size distribution shown in Table 1 was used and 1.5 parts by mass of methacrylsilane was added to 100 parts by mass of the heat-treated silica powder.

[0078] (Surface-treated silica powder 8) Surface-treated silica powder 8 was obtained in the same manner as surface-treated silica powder 1, except that silica powder having the particle size distribution shown in Table 1 was used and 0.6 parts by mass of methacrylsilane (manufactured by Shin-Etsu Silicones Co., Ltd.) was added instead of vinylsilane per 100 parts by mass of the heat-treated silica powder.

[0079] The obtained surface-treated silica powders 1 to 8 were stored in aluminum packs until immediately before various evaluations.

[0080] (specific surface area) The specific surface area of ​​the silica powder was measured by the BET one-point method using nitrogen gas adsorption. Specifically, using a specific surface area measuring device (manufactured by Anton Paar, device name: NOVA 800 BET), nitrogen gas was transported using a vacuum pump, and 0.1 to 5.0 g of sample was dried and degassed at 300°C for 30 minutes before measurement.

[0081] (particle size) The volume frequency particle size distribution of silica powder was determined by wet laser diffraction scattering using a particle size distribution analyzer (Coulter, LS13 320). A 0.2% aqueous solution of sodium hexametaphosphate was used as the solvent. The powder was pre-dispersed for 120 seconds or more using a homogenizer at 500 W output. The PIDS (Polarization Intensity Differential Scattering) concentration was adjusted to 45-55%. The refractive index of water was set to 1.33, while the refractive index of the powder was determined based on the refractive index of the powder material. For example, a refractive index of 1.50 was used for amorphous silica. Based on the obtained volume frequency particle size distribution, the particle size (D X ) was calculated.

[0082] (moisture content) The water content in the surface-treated silica powder was measured by the Karl Fischer method. Specifically, a trace moisture measuring device (Mitsubishi Chemical Corporation, Model CA-05) was used. The powder was placed in a quartz tube in a moisture vaporization mechanism, and heated from room temperature to 900°C using an electric heater while dehydrated argon gas was supplied as a carrier gas. The water vapor evaporated from the powder surface was introduced into the moisture measurement mechanism, and the moisture content was measured. The water generated by the time the heating temperature of the electric heater reached 200°C was considered to be physically adsorbed water, the water generated between 200°C and 550°C was considered to be water derived from hydrogen-bonded OH groups, and the water generated between 550°C and 900°C was considered to be water resulting from dehydration condensation of isolated OH groups.

[0083] <Production of Resin Composition> The copolymer shown in Table 1 was dissolved in toluene, and 1 part by mass of a curing agent, Perbutyl P (manufactured by NOF Corporation), per 100 parts by mass of the copolymer was added and dissolved, followed by stirring and mixing to obtain a varnish-like composition. The surface-treated silica powder shown in Table 1 was added to the obtained varnish-like composition and stirred to obtain a slurry-like resin composition in which the volume ratio of the copolymer to the surface-treated silica powder was 50 vol %:50 vol %.

[0084] [Table 1]

[0085] The resulting resin compositions were evaluated for the following items.

[0086] <Measurement of dielectric loss tangent>

[0087] The resulting resin composition was stirred in a Thinky Mixer (Thinky Corporation) and then poured onto a PTFE sheet mounted on a silicone rubber mold (frame thickness: 0.5 mm or 1.0 mm) placed on a glass plate. The mixture was then vacuum dried at 80°C for 10 hours at 20 Torr. After drying, the silicone rubber mold was replaced with a stainless steel mold (frame thickness: 0.2 mm). The mixture was sandwiched between PTFE sheets and heated at 200°C for 2 hours under 10 MPa pressure in a heating press to obtain a cured sheet. A 30 mm x 40 mm x 0.2 mm sample was cut from the cured sheet and its dielectric loss tangent at 40 GHz was measured. A 40 GHz split cylinder resonator (EM Lab) was used as the measurement device. The measurement temperature was 25°C and humidity was 50% RH.

[0088] <Measurement of liquidity> The fluidity of the slurry resin composition prepared in the above <Measurement of dielectric tangent> was evaluated. Using a rheometer (e.g., Anton-Paar, product name "MCR302"), the viscosity was measured at a shear rate of 0.11 / s, a circular plate shape (10 mmφ), a sample thickness of 1 mm, and a temperature of 25±1°C. The fluidity was evaluated according to the following evaluation criteria, assuming the viscosity of Example 1 to be 100. Excellent: Less than 150 Good: 150 or more, less than 200 Defective: 200 or more

[0089] The results in Table 1 show that the resin compositions of Examples 1 to 5 are superior in low dielectric tangent compared to Comparative Examples 1 and 2, and superior in fluidity compared to Comparative Example 3.

Claims

1. an olefin-aromatic vinyl compound-aromatic polyene copolymer; a surface-treated silica powder; The surface-treated silica powder is In the volume frequency particle size distribution of the powder measured by a laser diffraction scattering method, when the particle diameter at which the cumulative value from the small particle diameter side is 10% is D10, the particle diameter at which the cumulative value is 50%, and the particle diameter at which the cumulative value is 90% is D90, (D90-D10) / D50 satisfies 0.8 or more and 4.5 or less, and The amount of water generated between 550°C and 900°C, as measured by the Karl Fischer method, is 500 ppm or less. Resin composition.

2. The resin composition according to claim 1, The specific surface area of ​​the surface-treated silica powder measured by the BET single-point method using nitrogen gas adsorption is 0.1 m ２ / g or more 12.0m ２ / g or less.

3. The resin composition according to claim 1 or 2, In the volume frequency particle size distribution of the surface-treated silica powder measured by the laser diffraction scattering method, the particle size at which the cumulative value from the small particle size side reaches 50% is defined as D50. The resin composition, wherein the surface-treated silica powder has a D50 of 0.1 μm or more and 10 μm or less.

4. The resin composition according to claim 1 or 2, The resin composition has a number average molecular weight Mn of 500 or more and 100,000 or less of the olefin-aromatic vinyl compound-aromatic polyene copolymer.

5. The resin composition according to claim 1 or 2, The resin composition has a water absorption rate of 1.0% or less of the olefin-aromatic vinyl compound-aromatic polyene copolymer.

6. A composite material set including a combination of raw material components used to produce a resin composition containing an olefin-aromatic vinyl compound-aromatic polyene copolymer and silica powder, a resin varnish containing an olefin-aromatic vinyl compound-aromatic polyene copolymer and a solvent; a surface-treated silica powder; The surface-treated silica powder is In the volume frequency particle size distribution of the powder measured by a laser diffraction scattering method, when the particle diameter at which the cumulative value from the small particle diameter side is 10% is D10, the particle diameter at which the cumulative value is 50%, and the particle diameter at which the cumulative value is 90% is D90, (D90-D10) / D50 satisfies 0.8 or more and 4.5 or less, and The amount of water generated between 550°C and 900°C, as measured by the Karl Fischer method, is 500 ppm or less. Composite materials set.

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