| 摘要 |
PROBLEM TO BE SOLVED: To provide spheric ferrite particles having specified distribution of particle size and almost no pore in the particles, particularly, useful as a carrier for an electrophotographic developer. SOLUTION: The particles are made of a ferrite expressed by (MO)<SB>100-</SB>X(Fe<SB>2</SB>O<SB>3</SB>)X, wherein M is at least one metal selected from Li, Mg, Ni, Cu, Zn, Mn, Ca and Fe, and X is 45 to 95 mol%, and have 1 to 45μm average particle size,≤0.2 m<SP>2</SP>/g BET specific surface area and≤0.05 ml/g pore volume measured by a mercury intrusion porosimetry method. COPYRIGHT: (C)2004,JPO |
