The invention relates to aqueous silica dispersion with a pH in the range from 8 to 14, comprising a base chosen from the group consisting of alkali metal hydroxides, (akyl)ammonium hydroxides or a mixture thereof, at least 35% by weight of silica particles surface-treated with an amino-organosilane (I) and/or a product of hydrolysis of compound of formula (I), 3% to 35% by weight of at least one polyol, 20% to 60% by weight of water, preparation of such dispersion and the use thereof in fire-resistant glass.

Provided is a means capable of introducing a sufficient amount of a cationic group onto the surface of silica particles even in a case where a silica raw material having a high silica concentration is used while occurrence of gelation is suppressed at the time of or after addition of a silane coupling agent in production of a cationically modified silica dispersion including modifying raw silica using a silane coupling agent. Adding a silane coupling agent having a cationic group to a silica raw material in which a zeta potential shows a negative value, and causing the silica raw material to react with the silane coupling agent to obtain a cationically modified silica.

Provided is a means capable of introducing a sufficient amount of a cationic group onto the surface of silica particles even in a case where a silica raw material having a high silica concentration is used while occurrence of gelation is suppressed at the time of or after addition of a silane coupling agent in production of a cationically modified silica dispersion including modifying raw silica using a silane coupling agent. Adding a silane coupling agent having a cationic group to a silica raw material in which a zeta potential shows a negative value, and causing the silica raw material to react with the silane coupling agent to obtain a cationically modified silica.

A silica-blended resin varnish contains a silica sol with a high dispersibility that is dispersed in a ketone organic solvent, in a nitrogen atom-containing polymer. The particles have an average size of 5 to 100 nm and have a carbon-carbon unsaturated bond-containing organic group and an alkoxy group bonded to surfaces thereof. The carbon-carbon unsaturated bond-containing organic group is bonded at 0.5 to 2.0 groups per unit area (nm.sup.2) of the particle surfaces. The alkoxy group is bonded at 0.1 to 2.0 groups per unit area (nm.sup.2) of the particle surfaces. The molar ratio of {(the carbon-carbon unsaturated bond-containing organic group)/(the alkoxy group)} is 0.5 to 5.0. The carbon-carbon unsaturated bond-containing organic group may be a phenyl group-containing organic group or a (meth)acryloyl group-containing organic group. An insulating resin composition contains the silica sol and a nitrogen-containing polymer, which may be polyimide, polyamide, polyamic acid, polyamide-imide, polyetherimide, or polyesterimide.

A silica-blended resin varnish contains a silica sol with a high dispersibility that is dispersed in a ketone organic solvent, in a nitrogen atom-containing polymer. The particles have an average size of 5 to 100 nm and have a carbon-carbon unsaturated bond-containing organic group and an alkoxy group bonded to surfaces thereof. The carbon-carbon unsaturated bond-containing organic group is bonded at 0.5 to 2.0 groups per unit area (nm.sup.2) of the particle surfaces. The alkoxy group is bonded at 0.1 to 2.0 groups per unit area (nm.sup.2) of the particle surfaces. The molar ratio of {(the carbon-carbon unsaturated bond-containing organic group)/(the alkoxy group)} is 0.5 to 5.0. The carbon-carbon unsaturated bond-containing organic group may be a phenyl group-containing organic group or a (meth)acryloyl group-containing organic group. An insulating resin composition contains the silica sol and a nitrogen-containing polymer, which may be polyimide, polyamide, polyamic acid, polyamide-imide, polyetherimide, or polyesterimide.

Embodiments of the disclosure provide an asymmetrically functionalized nanoparticle and a method for synthesizing the same. The asymmetrically functionalized nanoparticle includes a base nanoparticle. The base nanoparticle can include silicon dioxide. The base nanoparticle can have a lipophilic surface. A portion of the surface can be functionalized with a functionalizing material forming a hydrophilic portion. The functionalizing material can include polyethylenimine. A remaining portion of the surface is not functionalized forming a lipophilic portion. The asymmetrically functionalized nanoparticle is amphiphilic.

Embodiments of the disclosure provide an asymmetrically functionalized nanoparticle and a method for synthesizing the same. The asymmetrically functionalized nanoparticle includes a base nanoparticle. The base nanoparticle can include silicon dioxide. The base nanoparticle can have a lipophilic surface. A portion of the surface can be functionalized with a functionalizing material forming a hydrophilic portion. The functionalizing material can include polyethylenimine. A remaining portion of the surface is not functionalized forming a lipophilic portion. The asymmetrically functionalized nanoparticle is amphiphilic.

The present invention provides a means capable of further improving stability and washability under acidic conditions. The present invention is sulfonic acid-modified colloidal silica having an amount of sulfonic acid groups per 1 g of particles of 1.5 μmol/g or more and 13.0 μmol/g or less.

Embodiments of the invention include silica fiber compositions useful for treatment of animal wounds and tissue, as well as for other applications in industry. The fiber compositions may be formed via electrospinning of a sol gel produced with a silicon alkoxide reagent, such as tetraethyl ortho silicate, alcohol solvent, and an acid catalyst.

To provide modified colloidal silica capable of improving the stability of the polishing speed with time when used as abrasive grains in a polishing composition for polishing a polishing object that contains a material to which charged modified colloidal silica easily adheres, such as a SiN wafer, and to provide a method for producing the modified colloidal silica. Modified colloidal silica, being obtained by modifying raw colloidal silica, wherein the raw colloidal silica has a number distribution ratio of 10% or less of microparticles having a particle size of 40% or less relative to a volume average particle size based on Heywood diameter (equivalent circle diameter) as determined by image analysis using a scanning electron microscope.