Denki Kagaku Kogyo Kabushiki Kaisha | Date: 2013-07-18
Provided is a water-repellent, thermoplastic resin sheet including a textured layer which is formed from a polyethylene resin composition comprising a water repellent agent and which has a microscopic texture on one surface side, wherein at least the surface region of the textured layer is a cross-linked material which maintains the microscopic texture even after heated drawing. Also provided is a molded article, such as a molded container, formed by thermoforming the thermoplastic resin sheet.
Denki Kagaku Kogyo Kabushiki Kaisha | Date: 2014-01-16
Provided is a bladder for tire vulcanization superior in heat resistance and having a service time longer than before. A bladder for tire vulcanization prepared from an acrylic rubber composition at least comprising 100 parts by mass of an acrylic rubber containing structural units derived from (meth)acrylic acid alkyl ester in an amount of 94.5 to 99.5 mass % and structural units derived from (meth)acrylic acid alkyl ether in an amount of 0.5 to 5 mass %, 30 to 200 parts by mass of a carbon black having an arithmetical mean particle diameter, as determined according to JIS Z8901, of 20 to 30 nm and a DBP oil absorption of 70 to 130 ml/100 g, and 0.1 to 5 parts by mass of an imidazole compound as crosslinking agent.
Denki Kagaku Kogyo Kabushiki Kaisha | Date: 2014-03-07
Provided is a boron-nitride powder that is suitable for use in a resin composition for transmitting heat from a heat-producing electronic component such as a power device to a heat-dissipating member. The boron-nitride powder reduces thermal-conductivity anisotropy and thermal contact resistance, resulting in high thermal conductivity, and contains boron-nitride particles each consisting of hexagonal boron-nitride primary particles joined together. The boron-nitride powder, which is an aggregate of said boron-nitride particles, exhibits a mean sphericity of at least 0.70, a mean particle diameter of 20-100 m, a porosity of 50-80%, a mean pore diameter of 0.10-2.0 m, a maximum pore diameter of at most 10 m, and a calcium content of 500-5,000 ppm. Under X-ray powder diffraction, the graphitization index of the boron-nitride powder is preferably between 1.6 and 4.0, inclusive, and the peak intensity ratio (I(002)/I(100)) between the (002) plane and the (100) plane is preferably at most 9.0.
Denki Kagaku Kogyo Kabushiki Kaisha | Date: 2014-01-23
There is provided an alumina fiber capable of fixing a honeycomb carrier while maintaining elasticity for a long period of time even in a severe usage environment, and an alumina fiber aggregate formed of the fiber. Problems in a gripping material of an automotive honeycomb carrier are solved by applying an alumina fiber containing from 70 to 98% by mass of alumina and from 2 to 30% by mass of silica, having an average fiber diameter of from 3.0 to 8.0 m, a ratio of fibers having a fiber diameter exceeding 10 m being 5% or less in terms of the number of fibers and a size of a mullite crystallite contained in each fiber of from 10 to 1500 , and by forming an alumina fiber aggregate by using the fibers.
Denki Kagaku Kogyo Kabushiki Kaisha | Date: 2013-07-29
A copolymer for improving heat resistance of a methacrylic resin which can achieve preservation of excellent transparency of the methacrylic resin and improvement in heat resistance, and can provide a molded product having excellent appearance, by adding the copolymer to the methacrylic resin, is provided. According to the present invention, a copolymer for improving heat resistance of a methacrylic resin, including: 45 to 85 mass % of an aromatic vinyl monomer unit; 5 to 45 mass % of a (meth)acrylic acid ester monomer unit; and 10 to 20 mass % of an unsaturated dicarboxylic acid anhydride monomer unit; wherein the copolymer has a total light transmittance of 88% or more, the total light transmittance being measured in accordance with ASTM D1003 for a sample with 2 mm-thickness, is provided.