| 摘要 |
<p>PURPOSE:To obtain the title powder of excellent water repellency, by surface- treating a polymethylsilsesquioxane powder with a specified organosilicon compound. CONSTITUTION:A polymethylsilsesquioxane powder (A) which has an independent substantially exactly spherical form, a mean particle diameter of 0.1-20mum and such a particle diameter distribution that at least 80% of the particles fall within the range of a mean particle diameter + or -30% is surface-treated with an organosilicon compound (B) of the formula [wherein R is an unsubstituted monovalent hydrocarbon group, a is 1-2, Z is H, a halogen, OH, -OR', -NR'X, -ONR'2 or -OOCR' when a is 1, and is -O-, -N(X)'- or -S- when a is 2, R' is a 1-4C alkyl, and X is H or R'], e.g., hexamethyldisilazane.</p> |
