Abstract: A powder containing: a first particle having a first crystal composition; and a second particle having a second crystal composition different from the first crystal composition, wherein each of the first crystal composition and the second crystal composition contains at least one selected from the group consisting of Ti2O3, ?-Ti3O5 and Ti4O7.

Abstract: To provide: a spherical crystalline silica powder which enables a resin molded article having a high coefficient of linear thermal expansion and a low dielectric tangent to be obtained; and a method for producing the same. Provided is a spherical crystalline silica powder in which the number of water molecules desorbed at 50° C.-1,000° C. when the temperature is increased from 25° C. to 1,000° C. at a condition of 30° C./min. is 10 ?mol/g or less, and in which 10 mass % or more of the total powder is ?-quartz crystal. Also provided is a method for producing a spherical crystalline silica powder, the method comprising: (i) heating a spherical amorphous silica powder to obtain a spherical crystalline silica powder; (ii) bringing the spherical crystalline silica powder into contact with an acid; and (iii) heating, at 800-1,400° C., the spherical crystalline silica powder treated by (ii).

Abstract: [Summary] One embodiment of the present invention provides a powder. The powder includes ZnO, Al2O3, and SiO2 as components. In a ternary phase diagram of the ZnO, the Al2O3, and the SiO2, the powder has a composition included in a rectangular area having as the four corners thereof (ZnO (mol %), Al2O3 (mol %), SiO2 (mol %))=(24, 13, 63), (19, 18, 63), (37, 12, 51), (32, 17, 51). The ratio (S001/S101) of the area S001 of a peak appearing in the range of 15°?2??17° and the area S101 of a peak appearing in the range of 24°?2??27° in an X-ray diffraction pattern is 0.001-0.07.

Abstract: Provided are oxide composite particles to be mixed with a resin to obtain a resin composition having low viscosity, low dielectric constant, and low dielectric loss tangent. The oxide composite particles containing silica and an oxide of aluminum (a single oxide or a composite oxide, or both), in which the oxide composite particles contain 50% by mass or more of an ?-cristobalite crystal phase, less than 5% by mass of an ?-alumina crystal phase, and 10% by mass or less of a mullite crystal phase, and an elemental ratio of aluminum to silicon (aluminum/silicon) as determined by X-ray photoelectron spectroscopy is 0.01 to 5.0.

Abstract: Provided are oxide composite particles closer to a sphere that are mixed with a resin to obtain a resin composition having low dielectric constant and low dielectric loss tangent. The oxide composite particles containing silica and an oxide of aluminum (a single oxide or a composite oxide, or both), in which the oxide composite particles contain 10 to 90% by mass of an ?-cristobalite crystal phase, 50% by mass or less of an ?-alumina crystal phase, and more than 10% by mass of a mullite crystal phase, and an elemental ratio of aluminum to silicon (aluminum/silicon) as determined by X-ray photoelectron spectroscopy is 0.1 or more.

Abstract: Provided are spherical alumina particles to be mixed with a resin to obtain a resin composition having low dielectric loss tangent. The spherical alumina particles containing 90% by mass or more of an ?-alumina crystal phase, in which the spherical alumina particles have a half-width of an ?-alumina (113) peak of 0.124° or less as observed by X-ray diffraction and an average particle diameter of 0.5 to 40 ?m.

Abstract: A spherical silica powder with a low dielectric tangent, wherein after formulating the spherical silica powder in a resin and molding it into a sheet, in a dielectric tangent of the spherical silica powder calculated by using the following Formula (I) based on a dielectric tangent (tan ?c) of the sheet which is measured under the conditions a frequency is 35-40 GHz with a resonator method, B/A is 0.70 or lower, wherein “A” represents a dielectric tangent (tan ?fA) of the spherical silica powder before a dielectric tangent reduction treatment and “B” represents a dielectric tangent (tan ?fB) of the spherical silica powder after a dielectric tangent reduction treatment; and a specific surface area of said spherical silica powder after a dielectric tangent reduction treatment is 1-30 m2/g.

Abstract: To provide: an inorganic oxide powder which, when filled in a resin material, can simultaneously achieve a high dielectric constant and a low dielectric dissipation factor; a method for producing the same; and a resin composition comprising the inorganic oxide powder. Provided is an inorganic oxide powder comprising a spherical titanium oxide powder and an aluminum oxide powder, wherein the aluminum content in the inorganic oxide powder is 20-50,000 mass ppm. Further provided is a resin composition comprising the inorganic oxide powder and at least one resin material selected from a thermoplastic resin and a thermosetting resin.

Abstract: To provide: an inorganic oxide powder which, when filled in a resin material, can simultaneously achieve a high dielectric constant and a low dielectric dissipation factor; a method for producing the same; and a resin composition comprising the inorganic oxide powder. Provided is an inorganic oxide powder comprising a spherical titanium oxide powder having a rutile phase, wherein the ratio of the rutile phase in the inorganic oxide powder is 90 mass % or more. Further provided is a resin composition comprising the inorganic oxide powder and at least one resin selected from a thermoplastic resin and a thermosetting resin.

Abstract: A method for producing a particle, containing a step of heating a mixture containing TiH2 and TiO2 at 700 to 950° C., wherein a molar ratio of the TiH2 to the TiO2 contained in the mixture is 5.0 to 6.8.

Abstract: Provided are oxide composite particles to be mixed with a resin to obtain a resin composition having high thermal conductivity, low dielectric constant, and low dielectric loss tangent. The oxide composite particles containing silica and alumina, in which the oxide composite particles contain 40 to 85% by mass of an ?-cristobalite crystal phase, 5 to 50% by mass of an ?-alumina crystal phase, and 10% by mass or less of a mullite crystal phase, and an elemental ratio of aluminum to silicon (aluminum/silicon) as determined by X-ray photoelectron spectroscopy is 1.5 or more.

Abstract: Oxide powder, of which a resin composition is obtained by mixing with a resin exhibits a low thermal expansion coefficient, high thermal conductivity and a low dielectric tangent. The oxide powder containing Ca, Al and Si; wherein the oxide powder contains 40% by mass or more of a crystal phase of high-temperature type cristobalite having Ca, Al and Si, based on the mass of the whole oxide powder; and wherein contents of Ca, Al and Si in the oxide powder are 1 to 5% by mole of CaO, 1 to 5% by mole of Al2O3 and 90 to 98% by mole of SiO2, respectively (the sum of contents of CaO, Al2O3 and SiO2 is 100% by mole) when converting the contents of Ca, Al and Si to contents of CaO, Al2O3 and SiO2.

Abstract: A method for producing a particle, containing a step of heating a mixture containing TiH2 and TiO2 at 700 to 900° C., wherein a molar ratio of the TiH2 to the TiO2 contained in the mixture is 3.1 to 4.6. A particle having a crystal composition composed of Ti2O3 and ?-Ti3O5, wherein a molar ratio of the Ti2O3 to the ?-Ti3O5 is 0.1 or more.

Abstract: A method for producing a composite particle, the method containing: (a) mixing a raw material particle and at least one type of fine particles selected from SiO2 fine particles and Al2O3 fine particles, the fine paricles having a diameter smaller than that of the raw material particle; and (b) heating the mixture of the raw material particles and the fine particles, wherein the raw material particle contains three components of ZnO, Al2O3, and SiO2, and a content of the ZnO is 17 to 43% by mole, a content of the Al2O3 is 9 to 20% by mole, and a content of the SiO2 is 48 to 63% by mole, based on the total content of the three components.

Abstract: A spherical silica powder which, when heated from 25° C. up to 1000° C. at a rate of 30° C./min, desorbs water molecules in an amount of 0.01 mmol/g or less at 500° C. to 1000° C., and which has a specific surface area of 1 to 30 m2/g.

Abstract: A spherical silica powder with a low dielectric tangent, wherein after formulating the spherical silica powder in a resin and molding it into a sheet, in a dielectric tangent of the spherical silica powder calculated by using he following Formula (I) based on a dielectric tangent (tan ?c) of the sheet which is measured under the conditions a frequency is 35-40 GHz with a resonator method, B/A is 0.70 or lower, wherein “A” represents a dielectric tangent (tan ?fA) of the spherical silica powder before a dielectric tangent reduction treatment and “B” represents a dielectric tangent (tan ?fB) of the spherical silica powder after a dielectric tangent reduction treatment; and a specific surface area of said spherical silica powder after a dielectric tangent reduction treatment is 1-30 m2/g.

Abstract: One aspect of the present invention provides a powder containing three components of ZnO, Al2O3 and SiO2, wherein each content of the three components is ZnO: 17 to 43% by mole, Al2O3: 9 to 20% by mole and SiO2: 48 to 63% by mole, based on the sum of the contents of the three components.

Abstract: Provided is a spherical alumina powder which, when incorporated into resins in a high concentration, enables a resin composition to have low viscosity and which has reduced viscosity increase in the resin composition over time after surface treatment of the spherical alumina powder. The spherical alumina powder has an alkyl group(s) derived from a silane compound(s) on its surface, and is characterized in that an intensity ratio {I (CH3)/I (CH2)} of a peak (2960±5 cm?1) associated with asymmetric vibration of CH3 to a peak (2925±5 cm?1) associated with asymmetric vibration of CH2 in the alkyl group(s) of the silane compound(s) in the same spectral data obtained by infrared spectroscopic analysis measurement is 0.2 or more and less than 2.0.

Abstract: Provided is a spherical alumina powder which, when incorporated into resins in a high concentration, enables a resin composition to have low viscosity and which has reduced viscosity increase in the resin composition over time after surface treatment of the spherical alumina powder. The spherical alumina powder has an alkyl group(s) derived from a silane compound(s) on its surface, and is characterized in that an intensity ratio {I (CH3)/I (CH2)} of a peak (2960±5 cm?1) associated with asymmetric vibration of CH3 to a peak (2925±5 cm?1) associated with asymmetric vibration of CH2 in the alkyl group(s) of the silane compound(s) in the same spectral data obtained by infrared spectroscopic analysis measurement is 0.2 or more and less than 2.0.

Abstract: The present invention is to provide hollow particles with a low degree of agglomeration and having a high roundness, and a process for producing them. Hollow particles comprising a silicon compound, having an average particle size of from 5 to 65 nm and an average roundness of at least 0.90, and having a shell comprising the silicon compound and having a thickness of from 1 to 20 nm. Further, a method for producing hollow particles, which comprises adding sulfuric acid to a liquid containing spherical organic polymer-silicon compound composite particles having a core comprising an organic polymer and a shell comprising a silicon compound in a medium containing at least 95 mass % of water, followed by heating to carbonize the organic polymer thereby to convert it to a carbide, and subjecting the carbide to decomposition using a liquid oxidizing agent other than sulfuric acid.