| 摘要 |
PROBLEM TO BE SOLVED: To provide a ferrite carrier for an electrophotographic developer having low specific weight and high resistance, further having reduced variation in various characteristics such as resistance properties, magnetic properties, and surface properties, and to provide an electrophotographic developer having high durability, high reliability, and reduced image defects. SOLUTION: The ferrite carrier for the electrophotographic developer, which is a composite ferrite containing Li and Mg, is characterized in that when the composition of the ferrite is calculated as a mixture of Li ferrite having a stoichiometric composition and a Mg ferrite having a stoichiometric composition, the excessive amount of Fe<SB>2</SB>O<SB>3</SB>is less than 5 mol%, or the total excessive amount of Li<SB>2</SB>O and MgO is less than 1 mol%, the content of the elements other than Li, Mg, Fe and O is 2% by weight or less, and further, the content of Mn in terms of element is 1,000 to 9,000 ppm. COPYRIGHT: (C)2008,JPO&INPIT
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