| 摘要 |
PURPOSE:To improve the efficiency of removal of remaining toner by a cleaning means by reducing the extent of electrification of two kinds of remaining toner on a latent image carrier after the transfer process and weakening the electrostatic attraction between toner and the carrier. CONSTITUTION:After a charging corotron 12 is used to uniformly electrify a negative charge type photosensitive drum 11, it is irradiated with beam from a first laser 13 in accordance with image information to form a first negative image on the drum 11. Thereafter, a first developing device 14 to which a proper developing bias is applied is used to develop the negative image with red toner, thus obtaining a first toner image. After a second positive latent image is formed on the drum 11 by a second laser 15, a second developing device 16 is used to develop the second positive latent image with positive-polarity different color toner, thus obtaining a second toner image. Thereafter, polarities of respective toner images are equalized, for example, to the positive polarity by a transfer corotron 17 and they are transferred to a storage sheet 19, and thus, remaining toner is surely removed by a cleaner 21 because negative- polarity remaining toner remains on the drum 11 with a large extent of electrification and positive-polarity remaining toner remains there with neutral electric charge. |
