| 摘要 |
<p>A block or graft copolymer comprising a polyalkylene and a polysiloxane segment, preferably bonded via a trimethylene group, preferably of average mol. wt. 1000 to 20,000, is used to treat the surface of a powder, preferably of average diameter 100 mu m or less of a polyorganosilsesquioxane. …<??>The treatment can be by direct absorption, optionally with grinding, or using a solvent for the copolymer. …<??>The surface treated powder has a small specific gravity, good hydrophilicity and dispersibility in organic liquids and is useful e.g. in cosmetics.</p> |
