Silver masters for high-quality electrostatic printing

Du Pont has developed new silver electrostatic master technology suitable for making multiple copies of high quality prints. A digital laser image is captured by a multilayered silver halide film and diffusion transfer chemistry is used to form a unique conducting silver image in a polymeric insulating layer. For prints the silver master is corona charged; where there is a silver image, charge is bled off to an underlying ground plane and where there is no silver, charge is retained by the insulator. The charged master is then developed with high resolution liquid toners and the toner image transferred to paper. The charging, toning, and transfer steps are repeated for multiple copies. Quality is maintained at printing rates exceeding 8 inches per second. The silver master looks like a normal photographic film and is processed like one but has dual functionality; it can be used as an electrostatic printing master and as a normal photographic film, i.e., as a graphic arts intermediate. The master will be described in more detail and examples shown.