Developing device for an image forming apparatus

摘要

The invention provides a developing device using a non-magnetic type developer for developing an electrostatic latent image formed on an image carrying roller. The device comprises a developer carrying roller resiliently which is pressed against the image carrying roller and is formed of a conductive open-cell foam rubber material so that pore openings appear on the surface thereof to entrain and carry the developer to the surface of the image carrying roller for development of the electrostatic latent image. The device also comprises a developer regulating means engaged with the developer carrying roller for regulating the thickness of the developer entrained and carried thereby. The developer is composed of a toner component (T) and a resin powder component (P), one component of which has a polarity opposite to that of an electric charge of the other component generated by triboelectrification therebetween. The invention also provides an image formation apparatus, comprising such a developing roller and an image carrying roller for carrying an electrostatic latent image formed thereon.