摘要 |
PURPOSE:To stabilize Q/M and to enhance image density by forming a developer composed of a coated carrier having different kinds of laminated coating layers and a toner containing a positive polar material in a binder resin. CONSTITUTION:The developer is composed of the coated carrier having different kinds of laminated coating layers and a toner containing a positive polar material in the binder resin. As the material of the coating layers, conventional ones, such as styrene resins, acrylic resin, silicone resins, epoxy resins, polyamide resins, and fluororesins, call be used, and the core material of 50-1,000mum diameter is coated with said resins. It is preferred to use a combination of the second coating layer higher in surface energy than the first coating layer, thus permitting the obtained binary developer to be stabilized in Q/W, and accordingly, high image density to be maintained. |