EP 0549867 A3 19940720 - METHOD AND APPARATUS FOR DIRECTLY TRANSFERRING DEVELOPED IMAGES FROM A PHOTOCONDUCTIVE DRUM TO A PRINT MEDIUM
Title (en)
METHOD AND APPARATUS FOR DIRECTLY TRANSFERRING DEVELOPED IMAGES FROM A PHOTOCONDUCTIVE DRUM TO A PRINT MEDIUM
Publication
Application
Priority
US 80202891 A 19911203
Abstract (en)
[origin: EP0549867A2] Method and apparatus for electrophotographically transferring a developed color image on the surface of a photoconductive drum (10) directly to an adjacent print media (30). The print media (30) is operative to pass between the one abutting surface location on the photoconductive drum (10) and an adjacent surface location on a transfer roller (28) which is connected to receive a DC bias voltage (42). Once a composite color image has been developed on the surface of the photoconductive drum (10), this surface is illuminated with light (76) within a chosen wavelength range and intensity to thereby cause hole-electron pairs (88) within a layer (90) of the photoconductive drum (10) to recombine and thereby reduce the net voltage across the photoconductive surface layer or layers (78, 86, 90) to a level on the order of about thirty (30) volts (Fig. 2C). In this manner, the DC bias voltage (42) applied to the direct transfer roller (28) can be made larger than otherwise possible,thereby increasing the maximum achievable electrostatic field strength between the surface of the transfer roller (28) and the photoconductive drum (10). This feature of increasing the electrostatic field strength across the print medium (30) improves image transfer fidelity and print quality during the electrophotographic printing process. <IMAGE>
IPC 1-7
IPC 8 full level
G03G 15/01 (2006.01); G03G 15/16 (2006.01)
CPC (source: EP)
G03G 15/0131 (2013.01); G03G 15/167 (2013.01); G03G 15/169 (2013.01)
Citation (search report)
- [A] US 4897333 A 19900130 - MATSUSHITA KOUJI [JP]
- [A] US 4853736 A 19890801 - GOTO KOJI [JP], et al
- [A] US 4959695 A 19900925 - NISHIMURA KATSUHIKO [JP], et al
Designated contracting state (EPC)
DE FR GB IT
DOCDB simple family (publication)
EP 0549867 A2 19930707; EP 0549867 A3 19940720; JP H05265336 A 19931015
DOCDB simple family (application)
EP 92118751 A 19921102; JP 35030292 A 19921203