| 摘要 |
PROBLEM TO BE SOLVED: To enable satisfactory electrification and image formation by restricting excessive supply of electrification acceleration particles to the electrifying member of a contact electrifier, thereby steadily supplying it. SOLUTION: The contact electrifier has the electrifying roller 2 holding electrification acceleration particles (m) constituted of conductive particles, contacts a photoreceptive drum 1 via the electrification acceleration particles, and injects charges into the photoreceptive drum 1 by means of an applied electrification bias, thereby electrifying it. The developing unit 3 stores magnetic toner 31, in which the electrification acceleration particles (m) are mixed, attaches the electrification acceleration particles (m) to the photoreceptive drum 1 from a developing sleeve 32 in a developing part opposite the photoreceptive drum 1, and carries and supplies the electrification acceleration particles (m) to the electrifying roller 2 by means of the photoreceptive drum 1, thereby holding it there. In order to accelerate the supply of the electrification acceleration particles (m) to the electrifying roller 2, an amount of the charges after the restriction of toner 31 on the developing sleeve 32 by an elastic blade 34 is kept at 4-12 μC/g. |
