Electrophotographc process to release trapped charges by charging and ultraviolet exposure

In an electrophotographic process by the Carlson method, said method employing a composite photosensitive member including an electrically conductive supporting body, an intermediate layer of organic insulator for preventing charges from being injected from said supporting body, a photoconductive semiconductor layer having a charge generating function, and a transparent photo semiconductor layer having charge retentive and transporting functions, said layers being in the form of a stack in the recited order;

• and including the steps of uniformly charging said composite photosensitive member in one polarity;
• projecting a visible light image of a document to be copied to form an electrostatic latent image on the composite photosensitive member;
• developing the latent image with toners to form a toner image;
• transferring the toner image onto a record medium to form a copy;
• and erasing said electrostatic latent image after a plurality of copies have been formed from the same and single electrostatic latent image by repeating said developing and transferring, the improvement comprising:
• uniformly charging the composite photosensitive member in an opposite polarity and irradiating the composite photosensitive member with ultraviolet rays simultaneously with or immediately after said charging step to release charges trapped in the photoconductive semiconductor layer and the photo semiconductor layer of said composite member, said charges having been generated in the photoconductive semiconductor layer and the photo semiconductor layer during a duplication of a plurality of copies.