| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide ferromagnetic material powder in which the ratio of scattering magnetization, core material resistance and strength can be sustained at a high level when it is employed as a carrier core material and its production process, and to provide carrier for electrophotography developer employing that ferromagnetic material powder and its production process, and developer for electrophotography having excellent image density in which the adhesion of a carrier or a leak phenomenon is suppressed. <P>SOLUTION: In the ferromagnetic material powder composed of a magnetic oxide which is a complex of a magnetite phase and a ferrite phase, its crystal structure is constituted of a spinel type and a magneto-plumbite type, the content ratio of Fe<SP>3+</SP>at the A site in the spinel type crystal structure is 35-50% and the content ratio of Fe<SP>2+</SP>at the B site is 30-45%. <P>COPYRIGHT: (C)2008,JPO&INPIT |
