| 摘要 |
PURPOSE:To provide an electroviscous liq. having excellent stability and electrical response characteristics by conducting solvent replacement of a silica sol comprising a predetermined amt. of SiO2 dispersed in water or an org. solvent and using a non-reactive (modified) silicone oil having a predetermined specific gravity as a dispersion medium. CONSTITUTION:A silica sol comprising 5-50wt.% SiO2 dispersed in water or an org. solvent (e.g., methanol) is provided. Then, an electroviscous liq. is produced by conducting solvent replacement of the silica sol and using a non- reactive silicone oil or modified silicone oil having a specific gravity of 0.9-1.3 as a dispersion medium. Such solvent replacement can be attained by a method comprising distilling off water and low b.p. substances, a method comprising using an ultrafilter membrane, or other methods. The obtd. electroviscous liq. can be used in such a state that it is in direct contact with a rubber-like elastic material, because the electroviscous liq. does not contain any oil, solvent or the like which swells or dissolves the rubber-like elastic material. |
