| 摘要 |
PROBLEM TO BE SOLVED: To provide a tandem type image forming device which prevents failure in the carrying of a sheet in the formation of a monochromatic image while preventing the reduction in the service life of a transfer belt as much as possible. SOLUTION: In the case where a monochromatic image of black (K) is formed, the sheet carrying face of a transfer belt 13 is separated from photoreceptor drums 21C-20Y, and the operations of image forming units 20C-20Y including transfer rollers 26C-26Y are stopped. In the case, a system speed is set high so that, before an electrostatic attracting force for the transfer sheet S, exerted to the transfer belt 13 by an attracting charger 32, drops to the lowest limit of attracting force required to carry the transfer sheet, the transfer sheet S is transferred to the transfer position of a photoreceptor drum 21K. |
