| 摘要 |
PROBLEM TO BE SOLVED: To always stably form a normal image being free from a color slurring by a simple control, and to increase the printing efficiency by shortening the processing time. SOLUTION: In the case of forming an image of A4 size, the image forming device makes the toner image on a first side being formed on a photoreceptor 11 transferred on the intermediate transfer belt 21 in making the first reference mark detected by the mark signal as reference. When the device detects a third reference mark 27c on the intermediate transfer belt 21 by a third reference position sensor 25c, the toner image formed on the photoreceptor 11 based on this detection signal as the reference, the toner image on the second side is primary transferred on the intermediate transfer belt 21. By repeating this processing about every color toner image, the toner image on the first side and the toner image on the second side being transferred on the intermediate transfer belt is successively secondary transferred on transfer paper being successively fed. |
