MANUFACTURE OF MAGNETIC FLUID LIQ. AND MAGNETIZED PARTICLES COVERED WITH ORG. POLYMER FILM

摘要

PROBLEM TO BE SOLVED: To improve deposition stability and lower the wear property of a magnetic fluid liq. contg. magnetized grains and at least one kind of lipophilic liq. and arbitrary thickener. SOLUTION: A magnetic fluid liq. is obtd. which is composed of magnetized grains covered with an org. polymer film at 45-98wt.%, lipophilic liq. at 2-45wt.% and thickener at 0-20wt.%, total being 100wt.%. The org. monomer components are reacted in polycondensation, polyaddition or polymerization with the magnetizable grains to obtain an org. polymer. This polymer is deposited on the magnetized grains in the melt form or the solvent is evaporated from its soln. to deposit the polymer on the grains. If the grains are covered with silane before covering the polymer, the polymer covering can be easy.