| 摘要 |
PROBLEM TO BE SOLVED: To provide an image forming device which determines a transfer bias current in accordance with the difference of transfer paper and sets the intermediate transfer bias voltage of an intermediate transfer unit to an optimum value regardless of change of resistance characteristics or the like of an intermediate transfer body. SOLUTION: When a picture document having a painted-out picture area painted out with a uniform density is read in by a scanner part 11 to form a toner image on the transfer paper by a printer part 13, a system controller 12 changes the transfer bias current, which transfer part outputs at the time of transferring the toner image corresponding to the painted-out picture area, to plural stages to print and output toner images and reads in the picture on the transfer paper, where the toner image has been formed by the transfer bias current in each stage, as a document picture by the scanner part 11 to determine the most suitable transfer bias current value. The system controller 12 changes a transfer bias voltage to plural stages to set the transfer bias voltage to the optimum value in the same manner. |
