| 摘要 |
PURPOSE:To obtain a magnetic fluid, which has high saturation magnetization, is not gelled and has excellent dispersibility even under high centrifugal force of approximately 40000G, by using metallic particles manufactured by a specific dispersant and a special method. CONSTITUTION:The metallic particles of a magnetic fluid, desired saturation magnetization of which is acquired by changing concentration, are obtained by thermally decomposing cobalt carbonyl or iron carbonyl. At least one kind selected from alkyl or alkenyl succinic imide shown in formulae I and II and benzyl amine shown in formula III is employed as a dispersant dissolved into a solvent. In formulae, R represents an alkyl group or an alkenyl group, -R<1>-a 2-5C bivalent saturated fatty hydrocarbon group, (x) the integers of 0-10 and (y) the integers of 0-10. Accordingly, the magnetic fluid composition does not precipitate even under centrifugal force of approximately 40000G, and high dispersibility is acquired. |
