Abstract: A prepreg for printed wiring boards that has a low coefficient of thermal expansion in a plane direction, has excellent heat resistance and drilling workability, and, at the same time, can retain a high level of flame retardance includes a base material, a resin composition impregnated into or coated on the base material, and huntite. The resin includes (A) an inorganic filler that is a mixture composed of a hydromagnesite represented by xMgCO3.yMg(OH)2.zH2O wherein x:y:z is 4:1:4, 4:1:5, 4:1:6, 4:1:7, 3:1:3, or 3:1:4; (B) an epoxy resin; and (C) a curing agent. The prepreg can be used to prepare a laminated sheet and a metal foil-laminated sheet.

Abstract: It is an object of the present invention to provide, without using a halogenated compound or a phosphorus compound, a resin composition for printed wiring boards, a prepreg, a laminate, and a metal foil-clad laminate, each of which has high-degree flame retardance, has a low water absorption ratio and a high glass transition temperature, and has a high elastic modulus at high temperature. A resin composition according to the present invention includes a specific maleimide compound (A); a cyanate ester compound (B); a non-halogen epoxy resin (C); and an inorganic filler (D).

Abstract: A resin composition used as a material of an insulating layer of a printed wiring board including the insulating layer and a conductor layer formed on a surface of the insulating layer by plating, the resin composition including: an epoxy compound; a cyanate compound; a maleimide compound; an inorganic filler; and an imidazole silane, wherein the maleimide compound includes a predetermined maleimide compound, a content of the maleimide compound is 25% by mass or less based on 100% by mass of a total content of the epoxy compound, the cyanate compound, and the maleimide compound, and the imidazole silane includes a compound represented by the formula (3).

Abstract: The present invention provides a novel surface-treated molybdenum compound powder and provides a prepreg, a laminate, a metal foil laminate, a printed wiring board, and the like that have a low thermal expansion coefficient in the planar direction, and excellent drillability, heat resistance, and flame retardancy. The surface-treated molybdenum compound powder of the present invention has at least part of the surface thereof coated with an inorganic oxide, and this is used as a filler.

Abstract: An object of the present invention is to provide a resin composition that can attain cured products having high flame retardancy, high heat resistance, a small coefficient of thermal expansion, and high drilling processability, a prepreg having the resin composition, laminate and a metal foil clad laminate having the prepreg, and a printed circuit board having the resin composition. A resin composition, having at least an epoxy silicone resin (A) prepared by reacting a linear polysiloxane (a) having a carboxyl group with a cyclic epoxy compound (b) having an epoxy group such that the epoxy group of the cyclic epoxy compound (b) is 2 to 10 equivalents based on the carboxyl group of the linear polysiloxane (a), a cyanic acid ester compound (B) and/or a phenol resin (C), and an inorganic filler (D).

Abstract: A resin composition containing a cyclic epoxy-modified silicone compound (A) represented by formula (1), a cyanic acid ester compound (B) and/or a phenol resin (C) and an inorganic filler (D): wherein Ra each independently represent an organic group having an epoxy group; Rb each independently represent a substituted or unsubstituted monovalent hydrocarbon group; x represents an integer of 0 to 2; and y represents an integer of 1 to 6; and the siloxane unit marked with x and the siloxane unit marked with y are arranged mutually at random.

Abstract: There is provided a resin composition for printed wiring boards that, while maintaining excellent flame retardance, has excellent heat resistance, reflow resistance, and drilling workability, and, at the same time, has low water absorption without use of halogen compounds and phosphorus compounds. The resin composition comprises (A) a non-halogen epoxy resin, (B) a biphenyl aralkyl phenolic resin, (C) a maleimide compound and (D) an inorganic filler.

Abstract: The present invention provides a novel surface-treated molybdenum compound powder and provides a prepreg, a laminate, a metal foil laminate, a printed wiring board, and the like that have a low thermal expansion coefficient in the planar direction, and excellent drillability, heat resistance, and flame retardancy. The surface-treated molybdenum compound powder of the present invention has at least part of the surface thereof coated with an inorganic oxide, and this is used as a filler.

Abstract: It is an object of the present invention to provide, without using a halogenated compound or a phosphorus compound, a resin composition for printed wiring boards, a prepreg, a laminate, and a metal foil-clad laminate, each of which has high-degree flame retardance, has a low water absorption ratio and a high glass transition temperature, and has a high elastic modulus at high temperature. A resin composition according to the present invention includes a specific maleimide compound (A); a cyanate ester compound (B); a non-halogen epoxy resin (C); and an inorganic filler (D).

Abstract: It is an object to provide a prepreg for a printed laminate that has a low thermal expansion coefficient in the planar direction, excellent drillability, and further excellent heat resistance and flame retardancy, and a laminate and a metal foil-clad laminate. A resin composition according to the present invention includes a molybdenum compound (A); an epoxy resin (B); a curing agent (C); and an inorganic filler (D), wherein a Mohs hardness of the inorganic filler (D) is 3.5 or more, and a content of the inorganic filler (D) is 40 to 600 parts by mass based on 100 parts by mass of a total of resin solid components.

Abstract: There are provided a resin composition for printed wiring boards that has a low coefficient of thermal expansion in a plane direction, has excellent heat resistance and drilling workability, and, at the same time, can retain a high level of flame retardance, a prepreg prepared using the resin composition, and a laminated sheet and a metal foil-laminated sheet prepared using the prepreg. The resin composition comprises (A) an inorganic filler that is a mixture composed of a hydromagnesite represented by formula (1): xMgCO3.yMg(OH)2.zH2O??(1) wherein x:y:z is 4:1:4, 4:1:5, 4:1:6, 4:1:7, 3:1:3, or 3:1:4 and huntite; (B) an epoxy resin; and (C) a curing agent.

Abstract: There is provided a resin composition for printed wiring boards that, while maintaining excellent flame retardance, has excellent heat resistance, reflow resistance, and drilling workability, and, at the same time, has low water absorption without use of halogen compounds and phosphorus compounds. The resin composition comprises (A) a non-halogen epoxy resin, (B) a biphenyl aralkyl phenolic resin, (C) a maleimide compound and (D) an inorganic filler.

Abstract: There is provided a resin composition that, despite the fact that the content of an inorganic filler is on approximately the same level as that of the conventional resins, can provide a cured resin product that has a low coefficient of thermal expansion in a plane direction and possesses excellent heat resistance and flame retardance.