Abstract: The invention discloses a novel method for the preparation of globular particles of a silicone resin or, in particular, a polyorganosilsesquioxane resin having properties suitable as an adjuvant in hair-care toiletry preparations by the hydrolysis condensation reaction of an organotrialkoxy silane compound such as methyl trimethoxysilane in an aqueous alkaline medium. Characteristically, the aqueous reaction medium is alkalified with ammonia or, preferably, an amine compound, e.g., mono(n-alkyl) amine compound, to have a specified pH value of 10.0 to 13.0 and the hydrolysis condensation reaction of the starting silane compound in the aqueous medium is conducted in the presence of metallic ions or, in particular, magnesium ions in a specified concentration of 1×10−5 to 1×10−2 mole/liter.

Abstract: The invention discloses an aqueous slurry of globular particles of a silicone-based composite elastomer consisting of titanium dioxide particles and a crosslinked silicone elastomer as the matrix for the titanium dioxide particles. The aqueous dispersion comprises from 10 to 60% of the globular elastomer particles of 0.1 to 100 &mgr;m diameter, from 0.1 to 30% by weight of a surfactant which is preferably an anionic surfactant such as a salt of a dialkyl sulfosuccinate and the balance of water. The aqueous dispersion of the globular elastomer particles is quite satisfactory as an ultraviolet-shielding adjuvant in water-base cosmetic or toiletry preparations in respect of good stability of dispersion, high ultraviolet-shielding power and surface lubricity.

Abstract: Disclosed are spherical particles of a polyorganosilsesquioxane resin have a unique optical properties when each particle has a core-cladding composite structure consisting of a core portion of, for example, a polymethylsilsesquioxane resin and a cladding layer of, for example, a polyphenylsilsesquioxane resin having refractive indices differing by at least 0.02, the diameter of the core portion being in a specified range relative to the diameter of the whole particle. Such particles of a core-cladding structure can be prepared by conducting the hydrolysis-condensation reaction of organotrialkoxysilanes, e.g., methyl trimethoxysilane and phenyl trimethoxysilane, in two successive steps by using different silane compounds or by using silane mixtures of different mixing proportion in the first and second step reactions.

Abstract: The invention discloses a novel method for the preparation of globular particles of a silicone resin or, in particular, a polyorganosilsesquioxane resin having properties suitable as an adjuvant in hair-care toiletry preparations by the hydrolysis condensation reaction of an organotrialkoxy silane compound such as methyl trimethoxysilane in an aqueous alkaline medium. Characteristically, the aqueous reaction medium is alkalified with ammonia or, preferably, an amine compound, e.g., mono(n-alkyl) amine compound, to have a specified pH value of 10.0 to 13.0 and the hydrolysis condensation reaction of the starting silane compound in the aqueous medium is conducted in the presence of metallic ions or, in particular, magnesium ions in a specified concentration of 1×10−5 to 1×10−2 mole/liter.

Abstract: The invention discloses an aqueous slurry of globular particles of a silicone-based composite elastomer consisting of titanium dioxide particles and a crosslinked silicone elastomer as the matrix for the titanium dioxide particles. The aqueous dispersion comprises from 10 to 60% of the globular elastomer particles of 0.1 to 100 &mgr;m diameter, from 0.1 to 30% by weight of a surfactant which is preferably an anionic surfactant such as a salt of a dialkyl sulfosuccinate and the balance of water. The aqueous dispersion of the globular elastomer particles is quite satisfactory as an ultraviolet-shielding adjuvant in water-base cosmetic or toiletry preparations in respect of good stability of dispersion, high ultraviolet-shielding power and surface lubricity.

Abstract: Disclosed is a powder consisting of particles of a cured fluoro-silicone rubber having a specified average particle diameter and a specified rubber hardness. The fluorosilicone rubber has a siloxane composition consisting of three types of units expressed by the unit formulas of [R1R2SiO2/2], [R22SiO2/2] and [R23SiO1/2], in which R1 is preferably a 3,3,3-trifluoropropyl group and R2 is preferably a methyl group, in such a proportion that the molar ratio of R1:(R1+R2) is in the range from 0.05 to 0.5. The powder is useful as an ingredient in a cosmetic or toiletry preparation to effect improved sustainability of the cosmetic finish and decreased unevenness of coloring on human skin.

Abstract: Amorphous spherical silica microparticulates having a specific surface area of 5-50 m2/g and a particle size distribution of 5-1,000 nm are added to toner particles to form an electrostatic image developer which has improved fluidity and cleaning characteristics. On account of the minimized impurity content of the spherical silica microparticulates, the developer is effective for high-quality and high-speed duplication.

Abstract: Provided by the invention is a water-base silicone composition suitable for the surface treatment of, in particular, rubber articles as the substrate to impart the surface with excellent abrasion resistance and lubricity. The composition comprises, as dissolved or dispersed in an aqueous medium: (A) 100 parts by weight of a diorganopolysiloxane, e.g., dimethylpolysiloxane, terminated at each molecular chain end with alkoxy or hydroxyl group and having a specified degree of polymerization; (B) 0.01 to 10 parts by weight of an organotrialkoxy silane compound such as methyl triethoxy silane; (C) 1 to 10 parts by weight of an organoalkoxy silane compound containing an amido group and a carboxyl group in the molecule such as a reaction product of 3-amino-propyl triethoxy silane and maleic anhydride; (D) 1 to 10 parts by weight of an organoalkoxy silane compound having an epoxy group in the molecule such as 3-glycidoxypropyl trimethoxy silane; and (E) 0.01 to 10 parts by weight of a curing catalyst.

Abstract: Proposed is a reliable method for the preparation of a water-base hair-care or skin-care toiletry preparation capable of imparting the hair or skin of the user with excellent touch feeling of smoothness and sleekness. The method comprises (a) preparing an aqueous dispersion of globular particles of a cured silicone rubber having a specified average particle diameter by the in situ crosslinking hydrosilation reaction in liquid droplets of a vinyl group-containing dimethylpolysiloxane and an organohydrogenpolysiloxane in combination in the presence of a surface active agent and (b) admixing a base mixture consisting of the principal ingredients of a water-base toiletry composition with a specified amount of the aqueous dispersion of the cured silicone rubber particles.

Abstract: Proposed is a thermoplastic resin-based film suitable as a wrapping material having good slipperiness of the surface without decreasing the high transparency and having high resistance against formation of scratches. The resin film is molded from a thermoplastic resin composition comprising a thermoplastic resin such as polypropylene and polycarbonate as the matrix and a specified amount of fine silicone-based composite particles each consisting of a core particle of a silicone rubber having a specified particle diameter and a coating layer thereon in a specified coating amount formed from a polyorganosilsesquioxane such as polymethylsilsesquioxane.

Abstract: Proposed is a novel organopolysiloxane composition in the form of a water-base emulsion suitable for use as a surface-coating agent on rubber articles such as automobile parts to impart excellent smoothness of the surface, abrasion resistance, adhesion to the rubber surface and so on. The composition comprises: (a) an organopolysiloxane having a viscosity of at least 10000 centipoise at 25.degree. C. and having a molecular structure consisting of the difunctional siloxane units and the trifunctional siloxane units terminated at each molecular chain end with a hydroxy group, in the form of an aqueous emulsion; (b) a hydrolysis-condensation product of an epoxy group-containing dialkoxy silane in the form of an aqueous emulsion; (c) a water-soluble organic amino compound having at least two amino groups in a molecule and containing no silicon atom; and (d) silicone rubber particles in the form of an aqueous dispersion, each in a specified weight proportion.

Abstract: Proposed is a powder of silicone rubber having improved flowability and dispersibility consisting of particles of a cured silicone rubber of which each particle has a coating layer of a polyorganosilsesquioxane resin in a specified coating amount. The powder is prepared by the admixture of an aqueous dispersion of a cured silicone rubber particles, which is preferably prepared by the hydrosilation reaction between a vinyl group-containing organopolysiloxane and an organohydrogen polysiloxane emulsified in an aqueous medium, with a trialkoxy silane compound such as methyl trimethoxy silane together with an alkaline compound, e.g., ammonia water, under agitation so that the hydrolysis-condensation reaction of the trialkoxy silane compound proceed to form a coating layer on the surface of the silicone rubber particles.

Abstract: Disclosed is a silicone-based coating composition in the form of an aqueous dispersion of organopolysiloxanes suitable for the surface treatment of a rubber article to impart the surface with excellent lubricity and abrasion resistance so as to be useful for upgrading, for example, wind shields in automobiles. The coating composition comprises, as the effective ingredients, four organopolysiloxanes each in the form of an aqueous dispersion or solution including (a) an organopolysiloxane having a branched molecular structure consisting of two types of the siloxane units of the general formulas R.sup.1.sub.2 SiO and R.sup.1 SiO.sub.1.5, in which R.sup.1 is a monovalent hydrocarbon group, (b) a hydrolysis-condensation product of an epoxy group-containing dialkoxy silane compound, (c) a hydrolysis-condensation product of an aminoalkyl group-containing dialkoxy silane compound and (d) cured silicone rubber particles in a specified proportion.

Abstract: A rubber compound comprising (A) an organopolysiloxane having at least two alkenyl groups in a molecule and (B) reinforcing silica powder is blended with (C) silicone elastomer particles obtained by reacting an organohydrogenpolysiloxane with a vinyl group-containing organopolysiloxane such that the molar ratio of .tbd.SiH group to --CH.dbd.CH.sub.2 group ranges from 1.2 to 5 and (D) a platinum catalyst to form a silicone rubber composition which cures into a product having high rubber strength despite the inclusion of silicone elastomer particles. The composition finds typical use as silicone rubber parts in copying machines.

Abstract: A process of producing hydrophobic titanium oxide fine particles, comprising the steps of dispersing titanium oxide fine particles in an aqueous alkaline solution, adding a trialkoxysilane to the resulting dispersion in an amount of 1 to 1,000 parts by weight per 100 parts by weight of the titanium oxide fine particles, and carrying out the hydrolysis, whereby a film of a hydrolysis condensation product of the trialkoxysilane is formed on the surface of the titanium oxide fine particles. According to the present invention, titanium oxide fine particles can be treated quite effectively to be rendered hydrophobic without damaging the powdery nature of the titanium oxide.

Abstract: The surface-modified polymethylsilsesquioxane spherical fine particles of this invention comprise polymethylsilsesquioxane spherical fine particles serving as nuclei, and at least one member of an alkyl group having two or more carbon atoms, an alkenyl group, a phenyl group, an epoxy group, an acryloxy group and an amino group is bonded to the surface of a particle. They are prepared by a process comprising the step of carrying out reaction in an aqueous suspension of polymethylsilsesquioxane fine particles in the presence of an alkali catalyst. The surface-modified spherical fine particles can have various organic groups on their surfaces, and are used in various fields such as rubbers, plastics, coating materials, inks, and cosmetics, depending on the types of the organic groups.