The Interaction between Distribution of Corona Current and Image Quality on the Transfer and Separation Process in Electrophotography

Abstract

We studied the influence of the distribution of corona current upon the quality of toner images on the transfer and separation process in electrophotography. The authors have measured the distribution of corona current over a photoconductor drum, and calculated changes in the electric field in the air gap layer between the drum and paper.
As a result we could clarify the following properties of the image quality on this process:
I) The image quality is influenced by the corona current of the transfer corona unit itself as well as that of the separation corona unit.
II) The highest reliability of paper separation and the highest quality of toner images cannot be simultaneously realized as far as the transfer and separation process uses a corona charging system. That is because the corona current when paper separation is most easily accomplished is different from that when the quality of toner images are best.
Therefore we conducted an experiment with an Al laser beam printer in order to inspect these properties and obtain generally good results.