PURPOSE: To prevent memory after-image development without decreasing the amount of charging by providing a detrapping process wherein a conductive flexible member applied with a bias voltage is brought into contact between a cleaning process and a charging process.
CONSTITUTION: Residual charges on a photosensitive drum 11 after toner transfer are removed by the front-surface exposure of a discharging lamp 21 and residual toner is removed by a cleaning mechanism 22, so that the photosensitive drum 11 has optical fatigue of order which can not be ignored. When detrapping is carried out previously by applying a bias voltage before the charging, surface charges are not neutralized in the earliest charging, so the optical fatigue is prevented completely. For the purpose, the bias voltage is applied from a conductive rubber roller 31 connected to one electrode of a power source 30 which is grounded at the other electrode. The level of the bias voltage depends up the kinds of the light source in use and an amorphous silicone photosensitive body and is generally 90W400V.
AZUMAGUCHI TERUAKI
YANO YASUSHI
YAMAMOTO KAZUO
KAWAKAMI YOSHINOBU
| JPS5654458A | 1981-05-14 |