| 摘要 |
PROBLEM TO BE SOLVED: To make productivity in the case of forming a monochrome image higher than the productivity at the time of forming the color image. SOLUTION: This image forming device is made possible to raise productivity at the time of successively forming black monochrome color image, more than 4 times the productivity at the color image forming time, by superimposing/ transferring the toner image in respective color (yellow, magenta, cyan and black) on the intermediate transfer body 5 in synchronization with the position of the reference mark 15 detected by a sensor 16, and at the time of forming the black monochrome image, by transferring the black monochrome color toner image on the intermediate transfer body 5 in non-synchronization with the position of the reference mark 15 detected by the sensor 16. |
