| 摘要 |
PROBLEM TO BE SOLVED: To provide an image forming device capable of restraining the occurrence of positive memory with simple constitution. SOLUTION: A developing roller 20 rotatably comes in contact with the surface of a photoreceptor 12 while imparting pressing force to the photoreceptor 12. Namely, the roller 20 is pressed toward the rotary shaft of the photoreceptor 12 by an elastic member such as a spring. Then, press-contact force (pressing force) between the photoreceptor 12 and the roller 20 is set so that toner concentration (IDd and IDpc) on the roller 20 may be changed before and after the roller 20 comes in contact with the photoreceptor 12. Thus, the press-contact force between the photoreceptor 12 and the roller 20 is made appropriate, so that the occurrence of the positive memory is restrained. Besides, the occurrence of a filming phenomenon is prevented by using pulverized toner. |
