The present invention related to a hollow silica particle including: a shell layer containing silica; and a space formed inside the shell layer, in which the hollow silica particle has a particle density as measured by a dry pycnometer density measurement using helium gas of 2.00 g/cm.sup.3 or more and a particle density as measured by a dry pycnometer density measurement using oxygen gas of lower than 2.00 g/cm.sup.3.

A sol of inorganic oxide particles is stably dispersed in a hydrophilic organic solvent containing a hydrocarbon such as a paraffinic hydrocarbon or a naphthenic hydrocarbon. The sol contains a dispersion medium containing an organic solvent containing a C.sub.6-18 paraffinic hydrocarbon, a C.sub.6-18 naphthenic hydrocarbon, or a mixture of these, a C.sub.4-8 alcohol having a carbon chain with a carbon-carbon bond in the molecule in an amount of 0.1 to 5% by mass in the entire dispersion medium, and inorganic oxide particles having an average particle diameter of 5 to 200 nm as measured by dynamic light scattering as a dispersoid, wherein the inorganic oxide particles contain a C.sub.1-3 alkyl group bonded to a silicon atom and a C.sub.4-18 alkyl group. The paraffinic hydrocarbon is a normal paraffinic hydrocarbon or an isoparaffinic hydrocarbon. The naphthenic hydrocarbon is a saturated aliphatic cyclic hydrocarbon substitutable with a C.sub.1-10 alkyl group.

The present invention relates to granular functionalized silicas, wherein the Hg pore volume (<4 μm) is more than 0.80 ml/g, d.sub.Q3=10% is more than 400 μm, d.sub.Q3=90% is less than 3000 μm, the ratio of d.sub.50 without ultrasound exposure to d.sub.50 after 3 min of ultrasound exposure is <4.00 and the carbon content is 1.0-15.0% by weight. The inventive granular functionalized silicas can be used as a support material, especially as a support for enzymes.

A method for preparing a composition including mineral particles functionalized by at least one organic group and having a specific surface defined according to the BET method greater than 500 m.sup.2/g, involves: —choosing a phyllosilicate composition, including mineral particles having a thickness of less than 100 nm, a largest dimension of less than 10 μm and belonging to the family of lamellar silicates; —choosing at least one functionalizing agent, from the group formed from the oxysilanes and oxygermanes having at least one organic group, —bringing the phyllosilicate composition into contact with a functionalizing solution including the functionalizing agent, so as to obtain a phyllosilicate composition including mineral particles functionalized by the organic group, while choosing the organic group from the group formed from the cationic heteroaryl groups, the quaternary ammonium groups and the salts of same. The phyllosilicate composition obtained by the method is also described.

Granular and/or shaped hydrophobic silica useful for thermal insulation materials are prepared by mixing hydrophilic silica with a hydrophobicizing agent at low temperature so the hydrophobicizing agent does not appreciably react, followed by deaeration and compaction.

Provided is a filler that has a low viscosity when mixed in a resin material and has reduced permittivity and dielectric loss tangent. The filler includes: a metal oxide particle material; and a polyorganosiloxane compound with which a surface treatment is performed on the metal oxide particle material and which is represented by general formula (1): (RO).sub.3Si—(SiR.sub.2—O—).sub.n—SiR.sub.3 (in general formula (1), each R is independently selected from among alkyl groups having 1 to 4 carbon atoms, and n is not less than 10 and not greater than 200). A resin composition obtained by containing the filler in a resin is suitable for an electronic material.

Provided are a composition including at least one selected from silica particles in a shape in which a plurality of spherical silicas are connected in a bead shape or silica particles in a shape in which a plurality of spherical silicas are connected in a plane, and a solvent, in which at least a part of hydroxy groups on a surface of the silica particles is treated with a hydrophobizing treatment agent which reacts with the hydroxy group; a film formed of the composition; a structural body; a color filter; a solid-state imaging element; and an image display device.

A dispersion liquid contains an inorganic oxide particle surface-treated with at least one of a compound represented by Formula Si(R.sup.A1)(X.sup.A1).sub.3 or a compound represented by Formula Si(R.sup.A2)(R.sup.A20)(X.sup.A2).sup.2, polysiloxane having at least one of a T unit represented by Formula [R.sup.B1SiO.sub.3/2] or a D unit represented by Formula [R.sup.B2R.sup.B20SiO], and an organic solvent, where a content of the polysiloxane is 0.5% to 39% by mass with respect to a total amount of the inorganic oxide particle and the polysiloxane, in which in the formula, R.sup.A1, R.sup.A2, R.sup.B1, and R.sup.B2 represent a functional group, X.sup.A1 and X.sup.A2 represent a hydroxyl group or a hydrolyzable group, and R.sup.A20 and R.sup.B20 represent an alkyl group or an aryl group.

Disclosed is a coating composition which includes: polyurethane; and amphiphilic nanoparticles having an amine functional group and a fluorine functional group in their structure. Further provided are a polyurethane-silica composite film including e coating composition and a method of preparing the same.

Calcium silicate powders are provided. The calcium silicate powders comprise porous calcium silicate particles and an additive, the additive being at least partially penetrated into the pores of the particles. The additive is present in an amount of between 1.5 and 50%w, wherein %w is the weight ratio, expressed as percentage, of the dry weight of the additive over the dry weight of the combination of the calcium silicate particles and additive.