| 摘要 |
PROBLEM TO BE SOLVED: To provide a method for manufacturing alumina fine particles for an external additive suitable in obtaining a toner which has superior stability in frictional electrification and superior stability in photoreceptor electrification and also with which no leaking upon passing in toner replenishment control, no seal scattering upon toner replenishment, no fogging upon toner replenishment, and no photoreceptor memory occur; and a method for manufacturing the toner. SOLUTION: The method for manufacturing alumina fine particles for an external additive for a toner manufacturing spherical fine particles of alumina which are crystalline including aγ-alumina phase as a main phase and at least a small amount ofα-alumina phase and has a BET specific surface area of 20-80 m<SP>2</SP>/g, theγ-alumina phase being obtained when metal aluminum is evaporated by DC (direct current) arc plasma and then the vapor is oxidized. COPYRIGHT: (C)2010,JPO&INPIT |
