METHOD OF MULTICOLOR ELECTROPHOTOGRAPHIC PRINTING WITH UNIPOLAR TONER

摘要

A method for multicolor electrophotographic printing includes a photoconductive layer system having surface elements or surface regions that are provided with an initial negative potential, then are exposed to varying degrees and developed with negatively charged toner particles of a color. A uniform light source is arranged closed to the photoconductive layer system and then the surface elements are developed with a second color toner. In particular, the image being printed has image elements of different colors which correspond to different surface elements of the photoconductor. These surface elements are differently illuminated to achieve different potentials and are developed by color particles by depositing the color particles on the respective surface elements. The charge potential of ones of the surface elements is increased and then surface elements not covered by color particles are illuminated to reduce the charge potential there prior to subsequent development of further surface elements.