| 摘要 |
PROBLEM TO BE SOLVED: To form an image of high image quality while preventing ozone pro duction as much as possible by using a photoreceptor of straight polarity, an uncontacted electrifying means, and a developer of straight polarity, carrying residual developer onto the photoreceptor after transfer, and recovering it via an electrifying position. SOLUTION: A photoreceptor drum 20 is made of a positively electrified material, for example, a positively electrified organic photoreceptor. An electrifier 40 is composed of a scorotron type electrifier used for positive electrification, and is arranged opposite the photoreceptor drum 20 without being in contact with it. By varying a bias voltage, a cleaning roller 42 once attracts residual toner 53 after transfer by a transfer roller 60, and discharges it onto the photoreceptive drum 20 with specific timing to return it to a developing unit 50. A developing roller 56 uses positively electrified toner 53, and develops an image and also recovers the residual toner 53. Thus, because, even if the residual toner 53 is carried by the photoreceptor drum 20, it does not stick to the electrifier 40, the image with high image quality can be formed and ozone productionhardly occurs. |
