Electrophotographic process and apparatus therefor

An electrophotographic process using a photosensitive member for repeated image formations, wherein the photosensitive member essentially comprises a conductive layer, a photoconductive layer of a particular polarity type material, and an insulating layer, said process comprising the steps of:

• forming an electrostatic latent image on the photosensitive member;
• applying a developer to the latent-image-bearing photosensitive member;
• subjecting the developer-bearing photosensitive member to an additional processing step including applying a corona discharge of a polarity the same as the polarity type of the photoconductive layer to the photosensitive member, while said photoconductive layer is in a state wherein it retains an electric field thereacross, and exposing the photosensitive member to light to eliminate said electric field across the photoconductive layer.

An electrophotographic process using a photosensitive member for repeated image formations, wherein the photosensitive member essentially comprises a conductive layer, a photoconductive layer of a particular polarity type material, and an insulating layer said process comprising the steps of:

• forming an electrostatic latent image on the photosensitive member;
• applying a developer to the latent-image-bearing photosensitive member;
• subjecting the developer-bearing photosensitive member to an additional processing step including exposing the photosensitive member to light to provide said member with light hysteresis, and applying a corona discharge to the photosensitive member while said light hysteresis remains, wherein the corona discharge has a polarity which is the same as the polarity type of the photosensitive layer.

In an electrophotographic process for a repeated image formation using a photosensitive member essentially comprising a conductive layer, a photoconductive layer an insulating layer, an improvement is characterized by a primary charging step to uniformly apply a charge of a predetermined polarity to the photosensitive member, an exposure step of a light image corresponding to the image to be reproduced, a secondary charging step for applying a corona discharge to the photosensitive member substantially simultaneously with the light image exposure, the corona discharge having a component of a polarity opposite to the polarity of the primary charge, a whole surface exposure step to expose the whole surface of the photosensitive member, a developing step to develop the image with a developing agent of the same polarity as of the polarity of the primary charge, a transfer step to apply a corona discharge from the back of a transfer material of a polarity opposite to the polarity of the particles of a developing agent, a light exposure step to uniformly expose the photosensitive member and a cleaning step to clean the surface of the photosensitive member.