A method for production of coated mineral grit for the manufacture of coating elements with a bituminous support, or with a support comprising a vinyl or acrylic adhesive, for roofing of buildings, the method includes: adding rough mineral grit to a mixer together with a first treatment mixture; mixing the rough mineral grit and the first treatment mixture until a coated mineral grit is obtained; heating the coated mineral grit to a predetermined firing temperature (Tc); and after heating the coated mineral grit, cooling the coated mineral grit to a predetermined intermediate cooling temperature (Tri). The first treatment mixture comprises: water; at least one pigment; at least one selected from the group consisting of sodium silicate and potassium silicate; kaolin; and at least one selected from the group consisting of an organo-siloxane and an organo-silane.

A method for production of coated mineral grit for the manufacture of coating elements with a bituminous support, or with a support comprising a vinyl or acrylic adhesive, for roofing of buildings, the method includes: adding rough mineral grit to a mixer together with a first treatment mixture; mixing the rough mineral grit and the first treatment mixture until a coated mineral grit is obtained; heating the coated mineral grit to a predetermined firing temperature (Tc); and after heating the coated mineral grit, cooling the coated mineral grit to a predetermined intermediate cooling temperature (Tri). The first treatment mixture comprises: water; at least one pigment; at least one selected from the group consisting of sodium silicate and potassium silicate; kaolin; and at least one selected from the group consisting of an organo-siloxane and an organo-silane.

The invention relates to polymer compositions containing inorganic or organic particles which either have been surface-treated before the production of the compositions or are dispersed by special polyether-modified siloxanes through the production of the compositions.

The invention relates to polymer compositions containing inorganic or organic particles which either have been surface-treated before the production of the compositions or are dispersed by special polyether-modified siloxanes through the production of the compositions.

The purpose of the present invention is to provide a composite pigment which can be dispersed and made into paint in a manner that saves labor compared with conventional flat emulsion paints, and which can achieve concealing properties and low glossiness (a luster reduction effect) without separately adding a matting agent. This composite pigment contains an inorganic compound and/or an organic compound, and a fixed extender pigment.

The purpose of the present invention is to provide a composite pigment which can be dispersed and made into paint in a manner that saves labor compared with conventional flat emulsion paints, and which can achieve concealing properties and low glossiness (a luster reduction effect) without separately adding a matting agent. This composite pigment contains an inorganic compound and/or an organic compound, and a fixed extender pigment.

Provided are a cured material having a high refractive index for an optical member obtained by preparing a stable dispersion with a small amount of dispersant, and a process for producing dispersion of fine inorganic particles which is capable of drastically shortening the dispersion process time without causing overdispersion under the conditions of high solid concentration and without using media having a small particle size, which are very expensive and for which available dispersing machines are limited. Provided are a process for producing dispersion of fine inorganic particles using a media type wet dispersing machine, which includes supplying the following (A) to (D) to the wet dispersing machine, provided that (D) is supplied last to the wet dispersing machine: (A) Zirconium oxide nanoparticle, (B) Silane coupling agent, (C) Dispersion medium, and (D) Dispersant;
a curable composition containing a dispersion obtained by the producing process; and a cured material obtained therefrom.

A silicon-containing oxide-coated aluminum nitride particle including an aluminum nitride particle and a silicon-containing oxide coating covering the surface of the aluminum nitride particle. The content of carbon atoms is less than 1000 ppm by mass, and an Si/Al atom ratio of the surface as measured by AES analysis is 0.29 or more and 5.0 or less. In another aspect, the coverage of the silicon-containing oxide coating covering the surface of the aluminum nitride particle as measured by LEIS analysis is 15% or more and 100% or less.

A silicon-containing oxide-coated aluminum nitride particle including an aluminum nitride particle and a silicon-containing oxide coating covering the surface of the aluminum nitride particle. The content of carbon atoms is less than 1000 ppm by mass, and an Si/Al atom ratio of the surface as measured by AES analysis is 0.29 or more and 5.0 or less. In another aspect, the coverage of the silicon-containing oxide coating covering the surface of the aluminum nitride particle as measured by LEIS analysis is 15% or more and 100% or less.

To provide a powder coating material capable of forming a film excellent in metallic hue, concealing property and weather resistance. The powder coating material comprises the following fluororesin (A), the following resin (B) and the following pigment (C) as constituents thereof, wherein the content of the pigment (C) is from 0.7 to 23 mass %; Fluororesin (A): a fluororesin having a fluorine content of at least 10 mass %; Resin (B): a resin having a SP value larger than that of the fluororesin (A), and the difference between the SP value thereof and the SP value of the fluororesin (A) is at least 0.4 (J/cm.sup.3).sup.1/2; Pigment (C): a pigment which is a metallic pigment covered with a covering material, and the SP value of the covering material exceeds the SP value of the fluororesin (A) and less than the SP value of the resin (B).