| 摘要 |
PROBLEM TO BE SOLVED: To provide an image forming method which can carry out stable electrostatic charging for a long period even when high-ratio images are continuously outputted by preventing a photosensitive body from having a defective electrostatic charging. SOLUTION: In a pre-rotation processing carried out prior to image formation, the photosensitive body 1 and a roller electrostatic charger 3 begin to be driven and at this time, an electrostatic charging roller is rotated at a rotating speed for discharge mode which is faster than that in normal image formation. It is confirmed that untransferred toner is discharged from the roller electrostatic charger. As the rotating speed of an electrostatic charging member is increased, the change to discharge the untransferred toner per unit time increases, so that the discharge efficiency of toner ticking on the electrostatic charging roller is improved. In the pre-rotation for image formation, a rotating speed having a 150% circumferential speed ratio to the circumferential speed of the photosensitive body is set as the discharge mode for image formation. After the pre-rotation, the rotating speed of the electrostatic charging roller is lowered to a 40% circumferential speed ratio for the image formation. |
