| 摘要 |
PROBLEM TO BE SOLVED: To obtain spherical silicone particles having very high sphericity, a narrow particle diameter distribution and good dispersibility by mixing a hydrophobic organic solvent with a surfactant soluble therein and having a specified HLB value at a specified ratio, adding a specified amount of water to the mixture to give a w/o type emulsion, and using the emulsion as a reaction medium to effect the hydrolysis and polycondensation of an organosilicon compound. SOLUTION: The HLB value of the surfactant used is 1-9. The weight ratio of a hydrophobic organic solvent to a surfactant is (10:90) to (94:6). An amount of water added is 10-180 pts.wt. based on 100 pts.wt. total of the organic solvent and the surfactant. The organosilicon compound used is represented by the formula: RnSi(OR')4-n (wherein n is 0 or 1; R is methyl, ethyl, vinyl or the like; and R' is lower alkyl). An example of the surfactant suitably used is a nonionic surfactant, preferably comprising a sorbitan ester of fatty acid, especially sorbitan trioleate. The organosilicon compound used preferably comprises methyltrimethoxysilane. The process is simple, wherein a shorter time is required for synthesis and it is not essential to use an acid or alkali catalyst.
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