Abstract: A silica particle includes: a quaternary ammonium salt, in which the following expressions are satisfied, 0.90?FBEFORE/FAFTER?1.10, and 5?FSINTERING/FBEFORE?20, in which FBEFORE represents a maximum frequency value of a pore diameter of 2 nm or less in the silica particles before washing, which is obtained from a pore distribution curve in a nitrogen gas adsorption method, FAFTER represents a maximum frequency value of the pore diameter of 2 nm or less in the silica particles after washing, which is obtained from the pore distribution curve in the nitrogen gas adsorption method, and FSINTERING represents a maximum frequency value of the pore diameter of 2 nm or less in the silica particles before washing and after sintering at 600° C., which is obtained from the pore distribution curve in the nitrogen gas adsorption method.

Abstract: A pressure sensitive adhesive particle includes a pressure sensitive adhesive base particle that contains a styrene resin containing styrene and a vinyl monomer other than styrene as polymerization components, and a (meth)acrylate resin containing at least two (meth)acrylates as polymerization components, in which a mass ratio of the (meth)acrylates relative to a total of polymerization components of the (meth)acrylate resin is 90 mass % or more; and an external additive. The pressure sensitive adhesive particle has a surface having an arithmetic average roughness Ra within a range of 0.005 ?m to 0.100 ?m. The pressure sensitive adhesive particle has at least two glass transition temperatures, and the difference between the lowest glass transition temperature and the highest glass transition temperature among the glass transition temperatures of the pressure sensitive adhesive particle is 30° C. or more.

Abstract: A plant protection agent includes a photocatalyst particle containing a titanium oxide compound. The surface of the photocatalyst particle is modified with a metal compound that includes a metal atom and a hydrocarbon group. The photocatalyst particle has absorption at a wavelength of 550 nm.

Abstract: A filter includes a filter medium having an average pore size of 1 to 5 mm, and photocatalyst particles deposited on the filter medium. The photocatalyst particle contains a titanium compound particle and a metal compound bonded to the surface of the titanium compound particle with an oxygen atom. The metal compound contains a metal atom and a hydrocarbon group. The titanium compound particle has absorption at wavelengths of 450 nm and 750 nm in the visible absorption spectrum of the titanium compound particle.

Abstract: An organic substance-attached porous inorganic oxide particle including porous inorganic oxide particle and an organic substance attached to the surface of the porous inorganic oxide particle. The organic substance-attached porous inorganic oxide particle satisfies a formula below (Cf?Ce)/2>1 where Cf represents the amount of carbon (atom %) measured by subjecting the surface of the particle to X-ray photoelectron spectroscopy (XPS) after the particle is washed, and Ce represents the amount of carbon (atom %) measured by subjecting the surface of the particle to X-ray photoelectron spectroscopy (XPS) after two-minute surface etching of the particle.

Abstract: Provided is a silica titania composite aerogel particle including a base particle in which an element ratio Si/Ti of silicon to titanium is greater than 0 and equal to or lower than 6. A BET specific surface area of the silica titania composite particle is within a range of 200 m2/g to 1200 m2/g, and the silica titania composite particle has absorption at wavelengths of 450 nm and 750 nm.

Abstract: A silica-titania composite aerogel particle includes: a base particle including silicon and titanium whose element ratio Si/Ti is more than 0 and 6 or less; and a surface layer present on the base particle and including a metal compound having a metal atom and a hydrocarbon group. The silica-titania composite aerogel particle has absorption at wavelengths of 450 nm and 750 nm in a visible absorption spectrum, has a BET specific surface area in the range of 200 m2/g to 1,200 m2/g, and has a value A in the range of 0.03 to 0.3. The value A is calculated by formula: A=(peak intensity of C—O bond+peak intensity of C?O bond)/(peak intensity of C—C bond+peak intensity of C?C bond). The peak intensity is obtained from a C is XPS spectrum.

Abstract: A filter includes a filter medium having an average pore size of 1 to 5 min, and photocatalyst particles deposited on the filter medium. The photocatalyst particle contains a titanium compound particle and a metal compound bonded to the surface of the titanium compound particle with an oxygen atom. The metal compound contains a metal atom and a hydrocarbon group. The titanium compound particle has absorption at wavelengths of 450 nm and 750 nm in the visible absorption spectrum of the titanium compound particle.

Abstract: A filter includes a filter body containing a paper sheet having a surface roughness of 1.0 ?m or more and 10.0 ?m or less, and a photocatalyst particle held on the filter body and having a surface to which a metal compound having a metal atom and a hydrocarbon group is bonded via an oxygen atom. The photocatalyst particle is formed of a titanium compound particle having absorption at wavelengths of 450 nm and 750 nm in a visible absorption spectrum.

Abstract: A plant protection agent includes a photocatalyst particle containing a titanium oxide compound. The surface of the photocatalyst particle is modified with a metal compound that includes a metal atom and a hydrocarbon group. The photocatalyst particle has absorption at a wavelength of 550 nm.

Abstract: A plant protection agent includes a photocatalyst particle including a titanium oxide compound. The surface of the photocatalyst particle is modified with a metal compound that includes a metal atom and a hydrocarbon group. The photocatalyst particle has absorption at a wavelength of 550 nm. The change in the absorbance of the photocatalyst particle at the wavelength of 550 nm which occurs when the photocatalyst particle is irradiated with white light having an illuminance of 3000 lux for 24 hours is 10% or more.

Abstract: A silica particle has a compression and aggregation degree of from 60% to 95% and a particle compression ratio of from 0.20 to 0.40.

Abstract: A titanium oxide aerogel particle has absorption at wavelengths of 450 nm and 750 nm in a visible absorption spectrum, a surface to which a metal compound containing a metal atom and a hydrocarbon group is bonded via an oxygen atom, a BET specific surface area in a range of 120 m2/g to 1,000 m2/g, and a value A is in the range of 0.03 to 0.3. The value A is calculated by formula: A={(peak intensity of C—O bond+peak intensity of C?O bond)/(peak intensity of C—C bond+peak intensity of C?C bond)}. In the formula, the peak intensity is a value determined from a C 1s XPS spectrum.

Abstract: A silica-titania composite has a BET specific surface area, as determined by BET analysis of a water vapor adsorption isotherm, in the range of 250 m2/g to 500 m2/g and a contact angle with water of 100° or greater. In the water vapor adsorption isotherm, an adsorbed amount at relative pressure P/P0=0.1 is in a range of 65 cm3/g to 120 cm3/g, an adsorbed amount at relative pressure P/P0=0.5 is in a range of 150 cm3/g to 300 cm3/g, and an adsorbed amount at relative pressure P/P0=0.9 is in a range of 350 cm3/g to 500 cm3/g.

Abstract: A titanium oxide aerogel particle includes a metallic compound that has a metal atom and a hydrocarbon group, the metallic compound being bonded to a surface of the aerogel particle via an oxygen atom. The titanium oxide aerogel particle has a BET specific surface area of 120 m2/g to 1000 m2/g, and has absorption at wavelengths of 450 nm and 750 nm.

Abstract: A silica composite particle includes a silica particle and a compound in which a metal atom selected from the group consisting of Ti, Al, Zr, V, and Mg bonds to an organic group through oxygen, the silica particle being surface-treated with the compound. A coverage of a surface of the silica composite particle with the metal atom is 0.01 at % or more and 30 at % or less. When a binding energy peak of O1s in an oxide of the metal atom is assumed to be MO1s, a binding energy peak of O1s in SiO2 is assumed to be SO1s, and a binding energy peak of O1s in the silica composite particle is assumed to be MSO1s, the binding energy peaks being detected by X-ray photoelectron spectroscopy, the formula 0.000452×X2?0.059117×X+SO1s<MSOs?(SO1s?MO1s)/100×X+SO1s is satisfied.

Abstract: A method for producing a silica composite particle including a silica particle and at least one compound in which an aluminum atom bonds to an organic group through oxygen. The method includes: (i) providing a silica particle dispersion liquid having a silica particle content of about 20 mass % or more; (ii) mixing and reacting a compound represented by formula (S1) and the silica particle dispersion liquid to obtain a slurry; (iii) providing the at least one compound; and (iv) then mixing and reacting the slurry with the at least one compound to form the silica composite particle.

Abstract: A silica-titania composite aerogel particle includes: a base particle including silicon and titanium whose element ratio Si/Ti is more than 0 and 6 or less; and a surface layer present on the base particle and including a metal compound having a metal atom and a hydrocarbon group. The silica-titania composite aerogel particle has absorption at wavelengths of 450 nm and 750 nm in a visible absorption spectrum, has a BET specific surface area in the range of 200 m2/g to 1,200 m2/g, and has a value A in the range of 0.03 to 0.3. The value A is calculated by formula: A=(peak intensity of C—O bond+peak intensity of C?O bond)/(peak intensity of C—C bond+peak intensity of C?C bond). The peak intensity is obtained from a C is XPS spectrum.

Abstract: Provided is a silica titania composite aerogel particle including a base particle in which an element ratio Si/Ti of silicon to titanium is greater than 0 and equal to or lower than 6. A BET specific surface area of the silica titania composite particle is within a range of 200 m2/g to 1200 m2/g, and the silica titania composite particle has absorption at wavelengths of 450 nm and 750 nm.

Abstract: A titanium oxide aerogel particle has absorption at wavelengths of 450 nm and 750 nm in a visible absorption spectrum, a surface to which a metal compound containing a metal atom and a hydrocarbon group is bonded via an oxygen atom, a BET specific surface area in a range of 120 m2/g to 1,000 m2/g, and a value A is in the range of 0.03 to 0.3. The value A is calculated by formula: A={(peak intensity of C—O bond+peak intensity of C?O bond)/(peak intensity of C—C bond+peak intensity of C?C bond)}. In the formula, the peak intensity is a value determined from a C 1s XPS spectrum.