| 摘要 |
PROBLEM TO BE SOLVED: To provide an image forming apparatus that can improve secondary transferability of a toner image to an irregular surface sheet by using a belt having a multilayer structure as an intermediate transfer belt 31, and can satisfactorily secondarily transfer a toner image to a smooth surface sheet.SOLUTION: A secondary transfer power source 39 is configured to output, as a secondary transfer bias, one in which a duty with a time during which electrostatic movement of toner from a belt side to a sheet side at a secondary transfer nip (time during which toner has positive polarity), out of a first time and a second time of a waveform of periodic variation, as a standard exceeds 50%. The configuration can suppress a reduction in the toner charge amount Q/M caused by injection of a reverse charge to a toner at the secondary transfer nip, and thereby enabling satisfactory secondary transfer of a toner image to a smooth surface sheet such as coated paper to suppress the occurrence of insufficiency in image density.SELECTED DRAWING: Figure 1 |
