| 摘要 |
PROBLEM TO BE SOLVED: To provide electrification magnetic particles excellent in durability and preferably used for a cleaner-less system, an electrophotographic device using the electrification magnetic particles and a process cartridge. SOLUTION: Electrification magnetic particles 15 form an electrification member arranged in contact with an electrophotographic photoreceptor 12 and electrifying the electrophotographic photoreceptor 12 when applied with a voltage. The magnetic grains 15 are ferrite grains mixed with phosphor 0.01-3 pts.wt. to ferrite 100 pts.wt. having the composition expressed by the general formula (MnO)x (MgO)y (Fe2 O3 )z , where x+y+z<=1, 0.2<x<0.5, 0.05<y<0.25, 0.4<z<0.6. The phosphor abundance ratio on the surface of the magnetic grains 15 is larger than the phosphor ratio of the whole magnetic grains 15. |
