A resin producing method is a method of producing a resin with which an insulating structure formed on an outer peripheral portion of a conductor is impregnated, the method including: a filler mixing step of mixing a nanofiller at a ratio of 15 wt % or more with an epoxy resin to form a mixture; a shear mixing step of causing the mixture to be subjected to shear mixing; a diluent mixing step of mixing a reactive diluent that reduces a viscosity of the epoxy resin, with the mixture after the shear mixing step; and a curing agent mixing step of mixing an acid anhydride curing agent with the mixture after the diluent mixing step.

A one-component thermosetting epoxy resin composition includes at least one epoxy resin A having on average more than one epoxide group per molecule, at least one latent hardener B for epoxy resins, at least one impact modifier D, at least one physical or chemical blowing agent E and fibrous anhydrous magnesium oxysulfate MOS. Thermally expandable epoxy resin compositions have improved adhesion, especially on metal substrates.

Provided is a method for producing a polymer, comprising: a first step for synthesizing a crude polymer by reacting a monomer containing a pyrimidinetrione structure, an imidazolidinedione structure, or a triazinetrione structure, in an organic solvent in the presence of a quaternary phosphonium salt or quaternary ammonium salt; and a second step for precipitating and separating a purified polymer by mixing a poor solvent with the crude polymer-containing solution obtained in the first step.

To provide an epoxy resin composition that exhibits excellent low-dielectric properties and that is excellent in copper foil peel strength and interlayer cohesion strength in a printed-wiring board application, as well as an active ester resin that provides the epoxy resin composition. An active ester resin having a polyaryloxy unit containing a dicyclopentenyl group and represented by the following formula (1), and a polyarylcarbonyl unit. Here, R.sup.1 represents a hydrocarbon group having 1 to 8 carbon atoms, R.sup.2 represents a hydrogen atom, or formula (1a) or formula (1b), and at least one R.sup.2 is formula (1a) or formula (1b); and n represents a number of repetitions of 1 to 5.

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Provided is a composition which is for forming a resist underlayer film and with which the amount of a sublimate derived from a low-molecular-weight component such as an oligomer can be reduced, the composition comprising, for example, an organic solvent and a polymer having a repeating unit represented by formula (1-1), wherein the content of a low-molecular-weight component having a weight average molecular weight of 1,000 or less is 10 mass % or less in the polymer.

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The present disclosure relates to rubber polymers of ethylene-glycidylmethacrylate-vinyl acetate polymer as modifiers in epoxy resins. In particular ethylene-glycidylmethacrylate-vinyl acetate rubber polymers comprising phthalic anhydride modified glycidyl methacrylate monomer units.

The present disclosure relates to rubber polymers of ethylene-glycidylmethacrylate-vinyl acetate polymer as modifiers in epoxy resins. In particular ethylene-glycidylmethacrylate-vinyl acetate rubber polymers comprising phthalic anhydride modified glycidyl methacrylate monomer units.

A resin composition for molding includes an epoxy resin, a curing agent, and an inorganic filler containing at least one selected from the group consisting of calcium titanate particles and strontium titanate particles, in which a total content of the calcium titanate particles and the strontium titanate particles is 30% by volume or more and less than 60% by volume with respect to the entire inorganic filler.

Provided is a sheet-like prepreg that has both a low coefficient of linear thermal expansion and high flexibility and offers excellent anti-warpage performance and cracking resistance. The sheet-like prepreg according to the present invention includes a curable composition and a sheet-like porous support impregnated with the curable composition. The sheet-like porous support is made from a material having a coefficient of linear thermal expansion of 10 ppm/K or less. The sheet-like prepreg gives a cured product having a glass transition temperature of −60° C. to 100° C. The curable composition includes one or more curable compounds (A) and at least one of a curing agent (B) and a curing catalyst (C). The curable compounds (A) include an epoxide having a weight per epoxy equivalent of 140 to 3000 g/eq in an amount of 50 weight percent or more of the totality of the curable compounds (A).

Provided is a sheet-like prepreg that has both a low coefficient of linear thermal expansion and high flexibility and offers excellent anti-warpage performance and cracking resistance. The sheet-like prepreg according to the present invention includes a curable composition and a sheet-like porous support impregnated with the curable composition. The sheet-like porous support is made from a material having a coefficient of linear thermal expansion of 10 ppm/K or less. The sheet-like prepreg gives a cured product having a glass transition temperature of −60° C. to 100° C. The curable composition includes one or more curable compounds (A) and at least one of a curing agent (B) and a curing catalyst (C). The curable compounds (A) include an epoxide having a weight per epoxy equivalent of 140 to 3000 g/eq in an amount of 50 weight percent or more of the totality of the curable compounds (A).