Abstract: The present invention provides a method of producing titanium oxide capable of maintaining a high content of an anatase form crystal phase at a low cost even under a high temperature environment. The method of producing titanium oxide includes a step of synthesizing titanium oxide by using an aqueous solution obtained by dissolving titanium tetrachloride and an ?-hydroxycarboxylic acid having 3 carboxy groups as a reaction liquid and bringing the reaction liquid to a reaction temperature of 60° C. or higher and the boiling point of the reaction liquid or lower, wherein the ratio of the amount (mol) of the ?-hydroxycarboxylic acid to the amount (mol) of Ti in the reaction liquid is 0.006 or more and 0.017 or less, and the concentration of Ti in the reaction liquid is 0.07 mol/L or more and 0.70 mol/L or less.

Abstract: Provided is a method of producing a titanium oxide in which titanium tetrachloride is hydrolyzed using a liquid-phase method. This method includes a step of adding an aqueous titanium tetrachloride solution to warm water having a higher temperature than the aqueous titanium rachloride solution, in which in the step, the temperature of the warm water is 30° C. to 95° C. and the aqueous titanium tetrachloride solution is added to the warm water such that an increase rate of titanium atomic concentration in the warm water is 0.25 mmol/L/min to 5.0 mmol/L/min, and a titanium atomic concentration in the warm water after the step is 280 mmol/L or lower.

Abstract: Provided is a method of producing a titanium oxide in which titanium tetrachloride is hydrolyzed using a liquid-phase method. This method includes a step of adding an aqueous titanium tetrachloride solution to warm water having a higher temperature than the aqueous titanium rachloride solution, in which in the step, the temperature of the warm water is 30° C. to 95° C. and the aqueous titanium tetrachloride solution is added to the warm water such that an increase rate of titanium atomic concentration in the warm water is 0.25 mmol/L/min to 5.0 mmol/L/min, and a titanium atomic concentration in the warm water after the step is 280 mmol/L or lower.

Abstract: Titanium dioxide having a ratio Dtop/D50 of 1 to 3, between the maximum particle diameter Dtop and the average particle diameter D50, as determined based on observing the primary particles by a field emission-type scanning electron microscope. A production process of the titanium dioxide comprises performing a vapor phase process of reacting a titanium tetrachloride-containing gas with an oxidative gas to produce titanium dioxide, wherein when the titanium tetrachloride-containing gas and the oxidative gas are reacted by introducing each gas into a reaction tube, the temperature in the reaction tube is from 1,050 to less than 1,300° C.

Abstract: The object of the present invention is to provide a method for fixing a silicon carbide seed crystal and a method for producing a silicon carbide single crystal which can produce a silicon carbide single crystal having high quality and no penetration defects, and the present invention provides a method for fixing a silicon carbide seed crystal on a pedestal including: a step of mirror polishing a surface of a pedestal on which a silicon carbide seed crystal is to be fixed; a step of irradiating atoms or ions to at least one of a seed crystal-side surface of the pedestal on which the silicon carbide seed crystal is to be fixed and a pedestal side-surface of the silicon carbide seed crystal which is to be fixed on the pedestal, in a vacuum; and a step of directly connecting the seed crystal side-surface of the pedestal and the pedestal side-surface of the silicon carbide seed crystal by bringing them into close contact and applying pressure to them in a vacuum.

Abstract: A process for producing a fine particulate titanium dioxide, comprising charging a fine particulate titanium dioxide powder in a resin bag, spraying water droplets having a liquid droplet diameter of 5 to 500 ?m to the powder in the bag, and closing the bag for storing the powder in the bag.

Abstract: The process for producing silicon carbide single crystals of the present invention comprises a step for growing single crystals of silicon carbide on a silicon carbide seed crystal by supplying a sublimed gas of a silicon carbide source material to the silicon carbide seed crystal arranged on a pedestal, wherein a spacing member composed of silicon carbide is arranged between the pedestal and the silicon carbide seed crystal, the spacing member is non-adhesively held on the pedestal by a supporting member, the silicon carbide seed crystal is adhered to the surface of the spacing member on the opposite side of the pedestal, and the spacing member and the supporting member are relatively arranged so that the adhesive surface of the spacing member adhered with the silicon carbide seed crystal is separated by 5 mm or more in the vertical direction from the lowest position of the supporting member.

Abstract: A seed crystal for silicon carbide single crystal growth (13) which is attached to the lid of a graphite crucible charged with a raw material silicon carbide powder. The seed crystal includes a seed crystal (4) formed of silicon carbide having one surface defined as a growth surface (4a) for growing a silicon carbide single crystal by a sublimation method, and a carbon film (12) formed on the surface (4b) opposite to the growth surface of the seed crystal (4). Further, the film density of the carbon film (12) is 1.2 g/cm3 to 3.3 g/cm3.

Abstract: A process for producing a fine particulate titanium dioxide, comprising charging a fine particulate titanium dioxide powder in a resin bag, spraying water droplets having a liquid droplet diameter of 5 to 500 ?m to the powder in the bag, and closing the bag for storing the powder in the bag.

Abstract: A dye sensitized solar cell comprising, as the dye electrode, a titanium oxide structure having an optical band gap (hereinafter referred to as “BG”) of 2.7 to 3.1 eV as calculated from absorbance measured by an integrating sphere-type spectrophotometer, or a metal oxide structure obtained by dry-mixing a plurality of metal oxide powder particles differing in the particle size or a metal oxide dispersion thereof, wherein assuming that the BG of raw material metal oxide is BG0 and the BG of metal oxide after the dry mixing is BG1, the (BG0-BG1) is from 0.01 to 0.45 eV, and a production method thereof are provided.

Abstract: A water-based polishing slurry for polishing a silicon carbide single crystal, wherein the slurry comprises abrasive particles having a mean particle size of 1 to 400 nm and an inorganic acid, and the slurry has a pH of less than 2 at 20° C.

Abstract: A method for producing an SiC single crystal comprises providing a low temperature region and a high temperature region in a crystal growth crucible (6); disposing a seed crystal substrate formed of an SiC single crystal in the low temperature region of the crystal growth crucible; disposing an SiC raw material in the high temperature region; and depositing a sublimation gas that sublimes from the SiC raw material on the seed crystal substrate to grow the SiC single crystal. A material used in the crucible member where the seed crystal is disposed is a material having a room-temperature linear expansion coefficient that differs from that of SiC by 1.0×10?6/K or less, and the crucible member where the seed crystal is disposed is made of Sic.

Abstract: The present invention relates to an inorganic powder having a frequency-size distribution with multiple peaks, wherein the peaks are present at least in the particle size regions from 0.2 to 2 ?m and from 2 to 63 ?m, preferably with the maximum particle size being 63 ?m or less, the average particle size being from 4 to 30 ?m, and the mode size being from 2 to 35 ?m. The inorganic powder of the present invention is useful as a filler for a high thermally conductive member in electronic component-mounted circuit board required to have electrical insulating property and heat radiating performance, in that a heat radiating member comprising the powder can have thermal conductivity, the powder can provide a resin composition having excellent withstand voltage characteristics for forming an insulative composition into a thin film and can be filled in the resin composition at a high density so as to improve heat radiating performance of the resin composition.

Abstract: A high-purity ultrafine particulate titanium dioxide with a reduced fluctuation of the adsorbed water content which is a large mass fluctuation factor in a fine particulate powder body, is provided. The fine particulate titanium dioxide has a BET specific surface area of 10 to 200 m2/g, wherein when a powder of the titanium dioxide in an amount of 2 to 5 g is spread in a 10 cm-diameter glass-made Petri dish to a uniform thickness and left standing in an environment at 20° C. and a relative humidity of 80% for 5 hours, the rate of change of mass based on the mass before standing is from ?5 mass % to 5 mass %.

Abstract: A surface modification method comprising bringing, into a high-temperature flame formed by use of a combustible gas and a combustion-supporting gas, inorganic oxide powder A having an average particle size falling within a range of 0.5 to 200 ?m as measured by means of laser diffraction/scattering particle size analysis and inorganic oxide powder B having a particle size calculated on the basis of its BET specific surface area of 100 nm or less, to thereby modify the surfaces of particles of the powder A by means of the particles of the powder B. A surface modification method comprising bringing, into a high-temperature flame formed by use of a combustible gas and a combustion-supporting gas, the inorganic oxide powder A; and bringing again the resultant powder into the high-temperature flame, to thereby modify the surfaces of particles of powder A.

Abstract: Titanium dioxide having a ratio Dtop/D50 of 1 to 3, between the maximum particle diameter Dtop and the average particle diameter D50, as determined based on observing the primary particles by a field emission-type scanning electron microscope. A production process of the titanium dioxide comprises performing a vapor phase process of reacting a titanium tetrachloride-containing gas with an oxidative gas to produce titanium dioxide, wherein when the titanium tetrachloride-containing gas and the oxidative gas are reacted by introducing each gas into a reaction tube, the temperature in the reaction tube is from 1,050 to less than 1,300° C.

Abstract: The present invention relates to a complex oxide having a BET specific surface area of about 10 to about 200 m2/g, comprising zinc oxide as a primary component, containing crystalline structures of both zinc oxide and silica, and exhibiting diffraction peaks in lattice planes (100), (002), and (101), which are X-ray crystallographically specific to diffraction peaks of crystalline zinc oxide, and in a lattice plane (101) which is X-ray crystallographically specific to the diffraction peak of crystalline silica.

Abstract: Coated zinc oxide particles in which the surfaces of zinc oxide particles are coated with a metallic soap exhibit excellent dispersibility in resin. A thermoplastic resin composition containing the particles and a molded product formed from the composition are endowed with excellent visible light transmission property and ultraviolet light shielding property.

Abstract: Alumina particles obtained from aluminum chloride by a gas phase method, the alumina having an amorphous form or a crystalline form of transition alumina, with primary particles thereof having an average particle diameter of approximately 5 to 100 nm, and secondary particles, resulting from the aggregation of the primary particles, having an average particle diameter of approximately 150 to 800 nm and wherein the particles having a secondary particle diameter larger than 45 ?m are contained in an amount of about 0.05% by mass or less.

Abstract: A process for producing titania-silica mixed crystal particles having a high bulk density and comprising titanium oxide as the main component and silicon oxide as a subsidiary component, the process comprising decomposing a gaseous titanium halide and a gaseous silicon halide, each heated at 600° C., or more in the presence of oxygen or water vapor heated at 600° C. or more, heating the obtained powder at 300 to 600° C. to decrease the concentration of raw material-originated hydrogen halide in the powder to 1 mass % or less, and then subjecting the powder to a treatment of dissociating the aggregated or steric structure.