Image forming apparatus which stably holds a uniform surface potential of a transfer device
US5697034A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Apr 12, 1996 |
| Grant date | Dec 9, 1997 |
| Priority date | — |
| Expiry date | Apr 12, 2016 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03G15/1685
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
An image forming apparatus has a photoreceptor drum whereon a toner image is to be formed, a transfer drum for transferring the toner image to a transfer material by making the transfer material contact with the photoreceptor drum, the transfer drum having a dielectric layer, semiconducting layer and conducting layer laminated in this order from a surface which comes into contact with the transfer material, a power source section for applying any voltage to the conducting layer, and a grounded conducting roller which is located in an upstream section in a transfer material transporting direction with respect to a transfer position on a surface of the dielectric layer and comes into contact with the dielectric layer surface through the transfer material. The volume resistivity of the dielectric layer is not lower than 40 percent of the volume resistivity of the semiconducting layer. In this structure, a current component flowing in the circuit is greater than a current component causing the dielectric layer to function as a power source, thereby accumulating charges on the dielectric layer. As a result, stable adhesion of the transfer material to the transfer drum, and improved imag…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.