Abstract: The laminate for a circuit board of the present invention is a laminate including a metal nitride sintered board and a copper sheet, and the laminate has a size with a minimum length from a center of a plane to a peripheral edge of 50 mm or more, and has a void ratio X of 0.50% or less, which is a ratio of a total length LB of voids having a diameter of 1 µm or more confirmed in the vicinity of a bonding interface of the metal nitride sintered board and the copper sheet with respect to a measured length LI of the bonding interface, measured on a cut cross section obtained by cutting the laminate in a lamination direction. According to the present invention, a laminate that is excellent in heat radiation capability, has a feature that an etching solution used in patterning is difficult to remain at the bonding interface, and is excellent in reliability as a product can be provided.

Abstract: A hexagonal boron nitride powder whose maximum absorption peak within the range of 3,100 to 3,800 cm?1 of the diffuse reflectance fourier transform infrared spectrum is existent at 3,530 to 3,590 cm?1 and which is able to provide high heat conductivity, dielectric strength and copper foil peel strength to a resin composition obtained by filling the powder into a resin, and a process for producing the above boron nitride powder by mixing together an oxygen-containing boron compound, a carbon source having a sulfur concentration of 1,000 to 10,000 ppm and an oxygen-containing calcium compound in a specific ratio and reduction nitriding the mixture.

Abstract: A hexagonal boron nitride powder whose maximum absorption peak within the range of 3,100 to 3,800 cm?1 of the diffuse reflectance fourier transform infrared spectrum is existent at 3,530 to 3,590 cm?1 and which is able to provide high heat conductivity, dielectric strength and copper foil peel strength to a resin composition obtained by filling the powder into a resin, and a process for producing the above boron nitride powder by mixing together an oxygen-containing boron compound, a carbon source having a sulfur concentration of 1,000 to 10,000 ppm and an oxygen-containing calcium compound in a specific ratio and reduction nitriding the mixture.

Abstract: To reduce scratches during polishing while ensuring an appropriately high polishing rate, provided are a silica for CMP satisfying the following (A) to (C), an aqueous dispersion using a silica for CMP, and a method of producing a silica for CMP: (A) a BET specific surface area of 40 m2/g or more and 180 m2/g or less; (B) a particle density measured by a He-gas pycnometer method of 2.24 g/cm3 or more; and (C) a coefficient of variation in primary particle diameter calculated by TEM/image analysis of 0.40 or less.

Abstract: To reduce scratches during polishing while ensuring an appropriately high polishing rate, provided are a silica for CMP satisfying the following (A) to (C), an aqueous dispersion using a silica for CMP, and a method of producing a silica for CMP: (A) a BET specific surface area of 40 m2/g or more and 180 m2/g or less; (B) a particle density measured by a He-gas pycnometer method of 2.24 g/cm3 or more; and (C) a coefficient of variation in primary particle diameter calculated by TEM/image analysis of 0.40 or less.

Abstract: There is provided particulate silica which can be suitably used as a viscoelasticity modifier such as a thickener which is added to liquid such as water, a liquid resin or paint to adjust its viscoelastic properties such as viscosity and thixotropic nature, a reinforcer or filler for silicone rubber or sealants, a polishing agent for CMP (Chemical Mechanical Polishing) or a surface coating agent for ink-jet printing paper. The particulate silica has a BET specific surface area S of 130 to 380 m2/g, and its fractal shape parameter ?1 in an ?-value analysis target range of 20 to 30 nm satisfies the following equation (1) and its fractal shape parameter ?2 in an ?-value analysis target range of 30 to 50 nm satisfies the following equation (2). ?1+0.00175S<2.518??(1) ?2+0.00174S<2.

Abstract: There is provided particulate silica which can be suitably used as a viscoelasticity modifier such as a thickener which is added to liquid such as water, a liquid resin or paint to adjust its viscoelastic properties such as viscosity and thixotropic nature, a reinforcer or filler for silicone rubber or sealants, a polishing agent for CMP (Chemical Mechanical Polishing) or a surface coating agent for ink-jet printing paper. The particulate silica has a BET specific surface area S of 130 to 380 m2/g, and its fractal shape parameter ?1 in an ?-value analysis target range of 20 to 30 nm satisfies the following equation (1) and its fractal shape parameter ?2 in an ?-value analysis target range of 30 to 50 nm satisfies the following equation (2). ?1+0.00175S<2.518??(1) ?2+0.00174S<2.

Abstract: Provided are a gas-barrier film which is a laminate comprising a substrate layer comprising a thermoplastic resin film and a gas-barrier layer comprising a hydrolysate of a silicon alkoxide, a stratified silicate and a polyvinyl alcohol base resin, wherein a radius (Rg) of gyration of a scattering matter which is measured by light scattering in the gas-barrier layer described above is 2.4 ?m or less, and the silicon alkoxide and/or the hydrolysate thereof are present between the layers of the stratified silicate present in the above gas-barrier layer. The above film shows an excellent gas-barrier property even under such a high humidity as exceeding 90% RH.

Abstract: Provided are a gas-barrier film which is a laminate comprising a substrate layer comprising a thermoplastic resin film and a gas-barrier layer comprising a hydrolysate of a silicon alkoxide, a stratified silicate and a polyvinyl alcohol base resin, wherein a radius (Rg) of gyration of a scattering matter which is measured by light scattering in the gas-barrier layer described above is 2.4 &mgr;m or less, and the silicon alkoxide and/or the hydrolysate thereof are present between the layers of the stratified silicate present in the above gas-barrier layer. The above film shows an excellent gas-barrier property even under such a high humidity as exceeding 90% RH.