JPS5735870A - Electrophotographing method - Google Patents

Abstract

PURPOSE:To obtain a 2-color copy partially changed in color, by using a photoreceptor prepared by laminating photosensitive layers different from each other in spectral sensitivity, exposing and developing it by a specified method. CONSTITUTION:A first photosensitive layer 12 sensitive to blue light but insensitive to red light, and a second photosensitive layer 13 sensitive to red light but insensitive to blue light are laminated on a conductive substrate 11 to form a photoreceptor 10, which is uniformly positively charged under blue light illumination, and then, uniformly negatively charged without illumination to negatively charge the surface of the photoreceptor 10. This is exposed to the optical image of a first original 21 having black image parts 19, 20 on the white background 18 to convert the surface potential of the photoreceptor corresponding to the white ground into zero. The photoreceptor 10 is exposed to the optical image of a second original 21' having a red part 22 corresponding to the region to be changed in color on a transparent colorless sheet using a black sheet as a background to form a positive surface potential of the photoreceptor corresponding to the red part 22. The photoreceptor is developed with a positively charged black toner 24 and a negatively charged red toner 25 to obtain the first original copy with the desired parts of the black image change into red.