| 摘要 |
The apparatus has multiple independent stations each having a master sleeve with an image in semipermanent fixed primary dielectric toner formed thereon. The image is transferred directly or by way of an intermediate transfer roll. The master sleeve is charged in light, the toned parts retaining charge. The resulting now charged image is toned with a pigmented secondary toner and this double toned image is pressed against the passing substrate or brough very close to it either directly or through the transfer medium. An electrical field is established between the substrate and the sleeve or transfer medium, the toner transferred to the substrate and the sleeve or transfer medium circulate back to pass through the same process of charge, tone and transfer. The transferred images are fixed between or during movement through the stations. Image density information can be used to control change in the electrical field conditions or other parameters. The impressions from each station are applied in registration. |
