Method and device for printing individual sheets with first and second printing groups and an inverter device

Abstract

In a method and system for printing, individual pages of a print medium are transported. With a printing unit, a side of the respective individual page facing it is printed and the applied toner image is fixed. With an inverter, the individual pages with the fixed toner image are inverted after the first printing event and resupplied to the printing unit for printing on an other side. The printing unit has first and second printing groups respectively comprising first and second exposure units, first and second charge corona devices, and first and second developer stations. Individual pages are supplied in succession to both of the first and second printing groups, and the printing groups respectively print two varicolored print images on the same side of the same individual page. A first latent image charge inked by the first developer station with toner of a first color is generated in each of the first and second printing units given a circulation of the intermediate carrier with aid of the first charge corona device and the first exposure unit. The second charge corona device and the second exposure unit subsequently generate a second latent charge image superimposed on the inked first latent charge image. The second charge image is inked by the second developer station with a toner of a second color.