CONTACT CHARGING OF PHOTORECEPTORS WITH CONDUCTIVE BRUSH-SLEEVE HYBRID ROLLER

Contact charging of organic photoreceptors (OPC) was studied, employin g a newly developed contact medium, a hybrid roller consisting of a co nductive brush and a conductive polymer sleeve. Bias voltage was appli ed between the OPC drum and the hybrid roller, and the surface potenti al of the OPC drum was monitored with a surface potentiometer. When in creasing the applied voltage, the OPC drum began to be charged at arou nd 500 V, which suggests that the charging of the OPC drum is mainly b ased on microdischarge. The threshold voltage for charging of the OPC drum with the hybrid roller decreased with an increase in the relative humidity of the atmosphere. These results indicate that carrier injec tion may also contribute to the charging of the OPC drums at high rela tive humidities. The generation of ozone was reduced to close to one-t enth its amount with corona charging. The uniformity of the surface po tential of the OPC drum was confirmed, and copy samples were obtained by applying the hybrid roller in a commercial photocopy machine.