| 摘要 |
PROBLEM TO BE SOLVED: To make always formable an image with proper transfer bias and to effectively prevent the occurrence of a defect in image such as irregularities in a transferred image, by preventing a material from being polarized because of the energization of a control electrifying member and this contact electrifying member from being high in resistance, accompanying the polarization, in an image forming device using a contact transfer system transfer means. SOLUTION: When a state, where the device is operated and a transfer material exists in a transferring part, is set as the time of transfer and a state, where the device is operated but the transfer material does not exist in the transferring part, is set as the time of passing no paper sheet, a bias for obtaining a polarity opposite to that of the transfer bias, when the paper does not pass through is applied to a contact transfer member, with a constant voltage or the bias is applied to the contact transfer member, so that a current flowing through the contact transfer member, when no paper is passing, has the polarity opposite to that when the transfer is being performed and the quantity of the current when no paper is passing is almost the same as that of the current after flowing through the contact transfer member when the transfer is being performed. |
