Analysis of Electrostatic Offset in Fuser Process

Abstract

In the fuser process of electro-photography, defects may be caused by a phenomenon called electrostatic offset, in which image smear is caused by toner from the fuser member adhering to the paper after one rotation of the fuser member. This toner is transferred from the paper to the fuser member by electrostatic force. The occurrence of electrostatic offset depends on the electrical resistivity of the fuser member and electric potential of the fuser delivery roller. In this study, we calculated the electric field of the fuser nip region, determined the shape of the fuser nip by structural calculation, and thus examined the physical mechanisms by which the electrostatic offset occurs. We also found that the occurrence of electrostatic offset can be predicted by the electric field strength of the fuser nip region and the electric charge distribution of toner.