| 摘要 |
PROBLEM TO BE SOLVED: To provide a ferrite carrier core material for an electrophotographic developer, the core material having appropriate ruggedness, strength, resistance and magnetization and excellent charging property, in particular, capable of maintaining high charging property and high resistance in a high temperature and high humidity environment, and showing less environmental dependency, and to provide a ferrite carrier, methods for producing the ferrite carrier core material and the ferrite carrier, and an electrophotographic developer using the ferrite carrier.SOLUTION: A ferrite carrier core material for an electrophotographic developer comprises a ferrite particle containing Mg by 0.9 to 3.5 wt.%, Ti by 0.3 to 2 wt.% and Fe by 66 to 71 wt.%, and having a FeO content of 1 to 6 wt.% and a pore volume of 0.010 to 0.025 ml/g. A ferrite carrier and methods for producing the carrier core material and the ferrite, and an electrophotographic developer using the ferrite carrier are also disclosed. |
