| 摘要 |
<p>PURPOSE:To recover untransferred toner instead of disposing it and to prolong service life of consumption parts. CONSTITUTION:Potential difference is formed between a developing device 14 and a photosensitive drum 11 to have the toner 17 from the developing device 14 stick to an image part and to have the toner 17a stuck to a non image part attracted to a developing device 14. The toner 17 is stuck to the image part by Coulomb's force due to the potential difference and developing is carried out by the developing device 14. An optical head 13 emits light with wave length which is outside a visual range and the toner 17 is characterized by having high transmissivity against light with wave length outside the visual range, and low transmissivity against the light with wave length within the visual range. Therefore, the photosensitive drum 11 is exposed by the light of the wave length outside the visual range emitted from the optical head 13 after passing through the toner. The toner 17a remaining on the non image part after the transfer is attracted and recovered to the developing device 14 with the Coulomb's force due to the potential difference when reaching the developing device 14.</p> |
