Abstract: A colloidal silica is disclosed that contains, with high purity, silica particles having an appropriate particle density, a high aggregation ratio, and a high alkoxy group content, and to provide a method for producing the colloidal silica in a simple manner at reduced costs. The colloidal silica containing silica particles is disclosed, wherein the silica particles have an average primary particle size of 33 nm or more, an aggregation ratio of 1.2 or more, and a particle density of 1.95 or more, the silica particles contain 1000 ppm by mass or more of alkoxy groups per gram of the silica particles, the proportion of the number of silica particles having an equivalent circle diameter under 20 nm is less than 15%, and the silica particles contain a primary amine in an amount of 5 ?mol or more per gram of the silica particles.

Abstract: A colloidal silica comprising water and silica particles, wherein the average particle size of the silica particles is 60 to 130 nm, and the content of coarse silica particles with a particle size of 0.2 ?m or more among the silica particles is 10,000,000 particles/mL or less at a silica particle concentration of 1 mass.

Abstract: A colloidal silica comprising water and silica particles, wherein the specific relaxation rate, as measured by pulsed NMR at a silica particle concentration of 3 mass %, is 0.60 or more, and the zeta potential of the surface of the silica particles in the pH range of 2 to 5 is ?10 to 10 mV.

Abstract: The present invention provides colloidal silica containing silica particles excellent in compactness and excellent in maintenance of the bumpy surface under basic conditions, and provides a method for producing the colloidal silica. The present invention provides colloidal silica containing silica particles having a bumpy surface, wherein (1) the silica particles have a content of alkoxy groups of 1000 ppm or more, and (2) the silica particles have a reduction in specific surface area of 15.0% or less when the silica particles are heated under basic conditions.

Abstract: The present invention provides colloidal silica containing silica particles excellent in compactness and excellent in maintenance of the bumpy surface under basic conditions, and provides a method for producing the colloidal silica. The present invention provides colloidal silica containing silica particles having a bumpy surface, wherein (1) the silica particles have a content of alkoxy groups of 1000 ppm or more, and (2) the silica particles have a reduction in specific surface area of 15.0% or less when the silica particles are heated under basic conditions.

Abstract: Provided is a hydrophobic silica powder that can be obtained by the sol-gel process, and that is excellent in charge properties. The hydrophobic silica powder has a hydrophobicity of 50% or more, a saturated water content of 4% or less, and a nitrogen content of 0.05% or more.

Abstract: The problem to be solved by the present invention is to provide colloidal silica for metal polishing that is capable of achieving a high polishing rate. This problem can be achieved by a colloidal silica for metal polishing, comprising a silica particle having a surface on which a functional group having at least one carboxyl group is immobilized by covalent bonding.

Abstract: The present invention provides colloidal silica that exhibits excellent abrasiveness and contains, with high purity, deformed silica particles with excellent compactness and a large amount of alkoxy groups per unit area; the invention also provides a method for producing the colloidal silica in a simple manner with reduced costs. The invention provides colloidal silica containing silica particles having a bent structure and/or a branched structure, wherein the silica particles have a particle density of 1.95 or more, the silica particles have a ratio (m/n) of the content of alkoxy groups m (ppa) to the average primary particle size n (nm) of 200 or more, and the silica particles having a bent structure and/or a branched structure are present in an amount of 15% or more based on the number of particles in a given field of view as observed with a scanning electron microscope at 200,000-times magnification.

Abstract: The present invention provides colloidal silica containing silica particles excellent in compactness and excellent in maintenance of the bumpy surface under basic conditions, and provides a method for producing the colloidal silica. The present invention provides colloidal silica containing silica particles having a bumpy surface, wherein (1) the silica particles have a content of alkoxy groups of 1000 ppm or more, and (2) the silica particles have a reduction in specific surface area of 15.0% or less when the silica particles are heated under basic conditions.

Abstract: A colloidal silica is disclosed that contains, with high purity, silica particles having an appropriate particle density, a high aggregation ratio, and a high alkoxy group content, and to provide a method for producing the colloidal silica in a simple manner at reduced costs. The colloidal silica containing silica particles is disclosed, wherein the silica particles have an average primary particle size of 33 nm or more, an aggregation ratio of 1.2 or more, and a particle density of 1.95 or more, the silica particles contain 1000 ppm by mass or more of alkoxy groups per gram of the silica particles, the proportion of the number of silica particles having an equivalent circle diameter under 20 nm is less than 15%, and the silica particles contain a primary amine in an amount of 5 ?mol or more per gram of the silica particles.

Abstract: The present invention provides a hydrophobic silica powder having a small particle size, a narrow particle size distribution, and a high hydrophobicity, and containing a very small amount of organic acid, and toner resin particles having the hydrophobic silica powder on the surface thereof. A hydrophobic silica powder having a particle size (D50) as measured by a laser diffraction method of 300 nm or less, a particle size distribution index (D90/D10) of 3.0 or less, a hydrophobicity of 60% by volume or more, and an organic acid content of 1 to 300 ppm.

Abstract: Colloidal silica containing silica particles that have a small particle size (e.g., an average primary particle size of 20 nm or less) and that contain alkoxy groups, and a method for producing the colloidal silica, are disclosed. The colloidal silica containing silica particles can have a small particle size and exhibit a suppressed increase in the average secondary particle size after storage. The colloidal silica containing silica particles wherein the silica particles have an average primary particle size of 20 nm or less, the silica particles have a ratio (m/n) of the content of alkoxy groups m (ppm) to the average primary particle size n (nm) of 300 or more, the silica particles have a particle density of 1.95 or more, and the silica particles have an increase rate of average secondary particle size of 12% or less in a storage stability test.

Abstract: An object of the present invention is to provide a metal oxide particle having a surface modified with a quaternary ammonium group, and a method for producing the particle. The present invention relates to a metal oxide particle having a surface modified with a silyl group and having an aggregation ratio (average particle size measured by dynamic light scattering/average diameter of primary particles measured in an SEM image) of 5.

Abstract: Provided is a hydrophobic silica powder that can be obtained by the sol-gel process, and that is excellent in charge properties. The hydrophobic silica powder has a hydrophobicity of 50% or more, a saturated water content of 4% or less, and a nitrogen content of 0.05% or more.

Abstract: This disclosure provides an agent for improving plant growth, the agent significantly improving resistances to a wide variety of stress possibly subjected to a plant, such as resistances to chemical stress and ultraviolet ray stress as well as resistances to temperature stress and dry stress, the agent having a high safety. This agent for improving plant growth alleviates an environmental stress on a plant, promotes plant growth, or a plant quality. This agent for improving plant growth contains, as its main ingredient, zerumbone, an analog of zerumbone, or a salt of zerumbone or the analog. Furthermore, in this agent for improving plant growth, the analog of zerumbone is ?-humulene or ?-caryophyllene.

Abstract: A hydrophobic silica powder is disclosed that exhibits reduced desorption of a charge control agent, on the charge-controllable surface, and that is capable of imparting charge properties within a suitable range to toner resin particles to which the hydrophobic silica particles are externally added. A hydrophobic silica powder is characterized in that (1) the hydrophobic silica powder has a hydrophobicity of 50% or more; (2) an amount X is 0.1 mass % or more, the amount X being an amount of at least one compound selected from the group consisting of a quaternary ammonium ion, a mono-azo complex, and a mineral acid ion extracted with a mixture solvent of methanol and a ethanesulfonic acid aqueous solution: and (3) the amount X and an amount Y satisfy the following formula (I): Y/X<0.15??(I), the amount Y being an amount of the at least one compound extracted with water.

Abstract: The present invention provides dense silica particles with reduced metal impurities. Specifically, the present invention provides a colloidal silica produced by using an alkyl silicate as a starting material, wherein, with respect to a sample prepared by adding, as an internal standard, 1 wt. % of polydimethylsilane to a dried product of the colloidal silica, a peak area value calculated using a formula of a colloidal silica peak area/a polydimethylsilane peak area is 15 or less, the peak areas being determined by an obtained solid-state 29Si-CP/MAS-NMR spectrum. The present invention further provides a method for producing the colloidal silica.

Abstract: This invention provides a dense, high-purity colloidal silica containing silica secondary particles having a branched and/or bent structure, and a production method thereof. Specifically, this invention provides a method for producing a colloidal silica, comprising the steps of 1) preparing a mother liquid containing an alkali catalyst and water, and having a pH of 9 to 12; and 2) adding a hydrolysis liquid obtained by hydrolysis of an alkyl silicate to the mother liquid, wherein the step of adding the hydrolysis liquid to the mother liquid sequentially comprises A) step 1 of adding the hydrolysis liquid until the pH of the resulting liquid mixture becomes less than 7; B) step 2 of adding an aqueous alkali solution until the pH of the liquid mixture becomes 7 or more; and C) step 3 of adding the hydrolysis liquid while maintaining the pH of the liquid mixture at 7 or more, and a colloidal silica containing silica secondary particles having a branched and/or bent structure, obtained by this method.

Abstract: This invention provides a high-purity, high-concentrated silica sol with long-term stability and low viscosity by preventing viscosity-increase after production, and method for producing the same. In one embodiment, the silica sol produced by an alkoxide method comprises at least a dispersing agent and silica, wherein the concentration of said dispersing agent is 10-3000 ppm with respect to the silica, wherein said dispersing agent may be an inorganic acid, inorganic acid salt, organic acid or organic acid salt whose degradation temperature and boiling point are both 60° C. or higher, wherein said silica sol has a silica concentration of 20% weight or higher.

Abstract: This invention provides a dense, high-purity colloidal silica containing silica secondary particles having a branched and/or bent structure, and a production method thereof. Specifically, this invention provides a method for producing a colloidal silica, comprising the steps of 1) preparing a mother liquid containing an alkali catalyst and water, and having a pH of 9 to 12; and 2) adding a hydrolysis liquid obtained by hydrolysis of an alkyl silicate to the mother liquid, wherein the step of adding the hydrolysis liquid to the mother liquid sequentially comprises A) step 1 of adding the hydrolysis liquid until the pH of the resulting liquid mixture becomes less than 7; B) step 2 of adding an aqueous alkali solution until the pH of the liquid mixture becomes 7 or more; and C) step 3 of adding the hydrolysis liquid while maintaining the pH of the liquid mixture at 7 or more, and a colloidal silica containing silica secondary particles having a branched and/or bent structure, obtained by this method.