| 摘要 |
PURPOSE:To selectively form a thin ferrite film on the surface of particles or a fibriform material by adding an oxidizing agent soln. to a deoxy-generated soln. contg. at least ferrous ion, particles and the fibrous material. CONSTITUTION:A deoxygenated soln. contg. at least ferrous ion (ferrous fluoride or the like) as a metallic ion, particles and/or a fibrous material (both average particle diameter and diameter are 100mu or below) is prepared. Further the metallic ion such as Zn<2+>, Co<2+>, Ni<2+> and Mn<2+> can be contained besides ferrous ion in this soln. and as particles, resin, organic pigment, metallic oxide and ceramic are used and as the fibrous material, each natural, synthetic and inorganic fiber can be used. Then this soln. is regulated to about 6-11pH and to about 60-90 deg.C temp. and an oxidizing agent soln. (nitrite, hydrogen peroxide and perchlorate, etc.,) is dropt. Thereby a ferrite film is selectively coated on the surface of particles and the fabriform material. |
