| 摘要 |
PURPOSE:To prevent an accumulation of a charge of an opposite polarity, to raise an image density and a contrast, and to improve a repeat characteristic of a photosensitive body, by constituting it so that a powder image is inverted forcibly by providing a charge of the opposite polarity, and it is transferred by providing a charge of the same polarity after a uniform exposure. CONSTITUTION:An electrostatic latent image is formed by exposing a photosensitive body 2 which has been electrified to the positive polarity by a corona electrifier 3, by an optical system 4, a toner powder which has been electrified to the positive polarity is carried to the photosensitive body by a developing device 5, and a powder image is inverted forcibly to the opposite polarity by a transfer corona discharge device 8. Subsequently, it is attenuated to a uniform potential by a pre-exposing device 10, a charge of the positive polarity of the same polarity is provided by a transfer corona discharge device 9, cleaning is executed by a device 14 after a transfer, and an exposure, a development and a transfer of the next processes are repeated. Accordingly, an accumulation of a charge of the opposite polarity is prevented, and prior to an image forming electrification, a trap in the photosensitive body is filled with a charge of a specific polarity, an image whose image density and contrast are high is obtained, and a repeat characteristic of the photosensitive body can be improved. |
