| 摘要 |
PURPOSE:To obtain the magnetic iron oxide powder having excellent magnetic convensional characteristics by a method whrein 0.5-10wt% of fatty acid of carbon number 6 or above or its metallic salt is added to the needle type hydrated ferric oxide particle obtained by the wet reaction of ferric salt solution and alkali. CONSTITUTION:When the needle type hydrated ferric oxide is oriented using an edge runner, and fatty acid or its metallic salt to be added should be one having a carbon number 6 or above. As the fatty acid, for example, caproic acid, caprylic acid and the like can be used. The quantity of the fatty acid or its metallic salt to be added should be within the range of 0.5-10wt%. Then, this particle is oriented in long axial direction with moisture below 75% using the edge runner. Subsequently, the above is turned to maghemite by performing dehydration by heating and restration to its former condition. According to this manufacturing method, the magnetic characteristics, especially the rectangular ratio, the degree of orientation and the density of residual magnetic flux of iron oxide powder are increased, and excellent electromagnetic conventional characteristics can be obtained. |
