METHOD AND EQUIPMENT FOR TONER IMAGE TRANSFER

摘要

PURPOSE: To provide the method and device for efficiently transferring a toner image from a charge holding surface to a copy sheet for 3-level xerography image formation. CONSTITUTION: A preliminary pretransfer process is performed so as to increase the transfer operation tolerance of a 3-level toner image or other multiple toner images having large differences of frictional charges. In a 1st example, electric charges of two multiple toner images are put close to each other by using a preliminary pretransfer corona device 80. In a following pretransfer process 70, the charge difference between the two images is reduce to give 3μc/g operation tolerance.