| 摘要 |
PURPOSE:To transfer and fix toner simultaneously on the surface and the rear of a paper and to operate a device at high speed by using two photosensitive bodies having the charging ability of opposite polarities, positive and negative ones. CONSTITUTION:A pair of photosensitive bodies 1 and 7 for forming an image having different charging characteristic is disposed to be opposed by putting a conveyance path L for the paper between them and chargers 4a and 4b, exposing devices 3a and 3b, developing devices 2a and 2b, blades 6a and 6b, erase lamps 5a and 5b are respectively arranged around the respective photosensitive bodies 1 and 7. In such case, the positive charging type photosensitive body 1 and the negative charging type photosensitive body 7 are respectively charged to be positive and negative by the chargers 4a and 4b. When an image part is irradiated with light by the exposing devices 3a and 3b, electric field is generated from the photosensitive body 1 to the photosensitive body 7 in a part where the two photosensitive bodies 1 and 7 face to each other and the positive toner and the negative toner on the photosensitive bodies are allowed to move to the opposed photosensitive body side respectively. However, since the paper fed from a paper feeding hopper 8 lies between the two photosensitive bodies 1 and 7, the positive toner and the negative toner are simultaneously transferred on the surface and the rear of the paper and fixed by a fixing device 10. Thus, the device is operated at high speed. |
