| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide a carrier core material for an electrophotographic developer, capable of fully calcining particles, even when a calcination temperature is turned to 1,000°C or lower, suppressing the crack and chip of carrier particles, even when mixed with toner and agitated over a long period of time, and obtaining stable image characteristics over a long period of time, and to produce the carrier core material at low cost. <P>SOLUTION: The mixture of iron sesquioxide powder, carbonate such as lithium carbonate, calcium carbonate, magnesium carbonate, barium carbonate or strontium carbonate, and a reducing agent is granulated, and then heat-treated at a temperature of 1,000°C or lower, in the hypoxic atmosphere of an oxygen concentration of 1.0×10<SP>-4</SP>ppm or lower. <P>COPYRIGHT: (C)2011,JPO&INPIT</p> |
