| 摘要 |
PURPOSE:To form an excellent copy image with good reproducibility even when its original has thin lines and a complicate pattern by forming an electrostatic latent image on a photosensitive body which is charged electrostatically to both polarities by laser light, and inverting the polarity of the latent image and performing development. CONSTITUTION:A three-layer photosensitive body constituted by sandwiching an amorphous silicon layer 31 which incorporates at least hydrogen between high- resistance layers 32 and 33 on a photosensitive body base layer 30 is used as a photosensitive body which has high spectral sensitivity to laser light and is charged to both polarities. The high resistance layers 32 and 33 incorporate >=1 kind among carbon, oxygen, and nitrogen in addition to hydrogen. The entire surface of this photosensitive body is charged uniformly to -600V and laser light of 780nm is scanned to form a latent image (-50V); and the entire surface is charged by a DC positive corona charger. When the amount of charge is made twice as large as the amount of negative charge, an exposed part is at +550V and an exposed part is at +70V, forming a positive image with negative toner. |
