Browse Prior Art Database

Original Publication Date: 1976-May-31
Included in the Prior Art Database: 2004-Mar-27

Publishing Venue

Xerox Disclosure Journal


Pre~transfer exposure of a toner developed photoreceptor 1 to a high intensity pre~transfer lamp 2 allows much of the image charge 3 to leak through the photoreceptor 1 to the grounded photoreceptor substrate 4. However, some image charge is trapped in place by the charge on the developed toner 5. A field imposed across the photoreceptor during this pre~transferexposure would cause some or all of this trapped charge to also conduct through the illuminated photoreceptor to ground. Reducing the image charge before transfer would reduce the force holding the toner to the photoreceptor, thereby improving transfer. It is proposed that a transparent conductive electrode 6 be used between the pre-transfer lamp 2 and the photoreceptor just up- stream of the transfer field generator 7, with the lamp 2 shielded to confine its light output through only part of the electrode 6. The electrode 6 would be biased to impose a field across the photoreceptor 1 which would drive the image charge toward the grounded substrate 4, This field would be applied beyond the area of the photoreceptor which is illuminated by the lamp 2 so the charges would be trapped adjacent the substrate 4 surface prior to the transfer of the toner to the copy sheet 8,