| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide ferrite magnetic powder which never deteriorates the special feature of a rubber bonded magnet, such as deformability and the like. <P>SOLUTION: The ferrite magnetic powder contains alkaline earth metal as a component, its chlorine content amounts to 0.05 wt.% or below, powder pH is kept below 6, and rubber resin is used as a binder to form the ferrite magnetic powder into a bonded magnet. The method of manufacturing the ferrite magnetic powder comprises the processes of grinding a burned material of ferrite composition containing alkaline earth metal as a component into powder, subjecting the powder to an annealing process for removing crystal distortion, dispersing the annealed powder into an aqueous medium to neutralize it with a mineral acid, then adding a dispersant to the aqueous medium where the annealed powder is dispersed, separating solid from liquid, and drying out the solid material in a reduced-pressure atmosphere to obtain the ferrite magnetic powder whose chlorine content is 0.05 wt.% or below and power pH is below 6. <P>COPYRIGHT: (C)2004,JPO&NCIPI |
