PRINTER OR COPIER FOR SIMULTANEOUSLY PRINTING A SUPPORTING MATERIAL ON BOTH SIDES

摘要

The invention relates to a printer or copier for simultaneously printing a supporting material on both sides. Two transfer bands (41, 42) transfer toner images (44, 45) onto a supporting material (43). A transfer corotron (47a) recharges the toner particles in the polarity thereof. The toner particles are transferred onto the supporting material (43) at the transfer point by an electric field (F). The invention also relates to a corotron device comprising counter-electrodes having small surfaces.