| 摘要 |
PROBLEM TO BE SOLVED: To eliminate the occurrence of an unelectrified part on a photoreceptor drum to prevent photographic fog in an image forming device. SOLUTION: A photoreceptor unit includes photoreceptor drums 1a, 1b, 1c, and 1d and electrifying means 2a, 2b, 2c, and 2d, and a development unit includes development rolls 4a, 4b, 4c, and 4d, and development rolls 4a, 4b, 4c, and 4d can be brought into contact with and be separated from the photoreceptor drums 1a, 1b, 1c, and 1d. At the time of non-printing, development rolls 4a, 4b, 4c, and 4d are separated from the photoreceptor drums 1a, 1b, 1c, and 1d, and rotation of these rolls is stopped; and at the time of printing, development rolls 4a, 4b, 4c, and 4d are brought into contact with the photoreceptor drums 1a, 1b, 1c, and 1d after a development bias and an electrifying bias are applied to development rolls 4a, 4b, 4c, and 4d and the photoreceptor drums 1a, 1b, 1c, and 1d while rotating them. |
