| 摘要 |
PURPOSE:To adjust a bicolor image density independently in each color, by changing bias voltages of respective color developing devices independently of each other when a bicolor image is formed by a composite photoreceptor where photosensitive layers different in spectral sensitivity are laminated. CONSTITUTION:Latent images different in charging polarity are formed on a composite photoreceptor where photosensitive layers different in spectral sensitivity are laminated, and these latent images are developed by developing devices using toners of corresponding polarities respectively. Bias voltages for development are changed in developing devices independently of each other. Thus, developing processes are not affected by each other, and the bicolor image density is adjusted as desired well in each color independently. |
