| 摘要 |
PURPOSE:To enable the prepn. of many sheets of copy by once image exposure by providing a photosensitive layer contg. a specified thioindigo compd. to an electrophotographic sensitive body. CONSTITUTION:A photosensitive layer consisting of, for example, a charge generating layer 2 and a charge transfer layer 3, is formed on an electroconductive base body 1, and a thioindigo compound expressed by formula I or II or its cis-isomer is incorporated into the layer 2. In the formulas, R is H or halogen, etc.; n is 0-4; m is 0-6. (i) A trans-form thio compd. is used for the whole part of the above described compd., then (ii) the compd. is image- exposed with light having a wavelength (lambda1) capable of causing a trans-cis isomerization, (iii) the surface of the photosensitive body is charged. Then, (iv) the whole surface is irradiated with light having a maximum wavelength (lambda4) corresponding to the absorption maximum of cis-form, (v) eliminating the surface potential of the cis-region and forming an electrostatic latent image. Thus, a copy is obtd. after developing with toner and transferring the developed image. When a same copy is to be obtd., the stage (iii) is executed again after cleaning the obtd. copy. When the copy is to be erased, (vi) the latent image is irradiated with light having a wavelength (lambda2) for isomerizing to trans-form. |
