PURPOSE: To provide a long-life two-component developer for electrostatic latent images which has stable triboelectricity between the toner and the carrier without being affected by changes of temp. or humidity, has stable triboelectricity even at continuous use, causes no deterioration of color characteristics even when the developer is used for a long time, and can maintain high quality picture images without edge effect.
CONSTITUTION: This electrophotographic developer consists of a carrier and a toner. The toner contains at least one of specified fluorine-contg. quaternary ammonium salt compd. or fluorine-contg. imnium compd. as a polarity controlling agent. The carrier has a structure having a coating layer comprising at least one of fluorine-contg. resin coating layer, fluorine-contg. resin coating layer containing silicone oil, silicone resin coating layer, or silicone resin coating layer containing silicone oil. Further, it is specified that the carrier coating layer contains silicone oil, fluorine-contg. resin, coupling agent, or the like.
ASAHINA YASUO
OKAMOTO YOSHINAO
KATO TAKAHISA
SUZUKI TOMOMI
MATSUDA HIROAKI
