EP 0381751 B1 19940112 - ELECTROPHOTOGRAPHIC METHOD.
Title (en)
ELECTROPHOTOGRAPHIC METHOD.
Title (de)
ELEKTROPHOTOGRAPHISCHES VERFAHREN.
Title (fr)
PROCEDE ELECTROPHOTOGRAPHIQUE.
Publication
Application
Priority
US 23207388 A 19880815
Abstract (en)
[origin: WO9001730A1] A multicolor reproduction is made by uniformly charging a photoconductive member (2), imagewise exposing that member to create a first electrostatic image, developing the first electrostatic image with a toner of a first color to create a first toner image, preferably uniformly recharging the photoconductive member, imagewise exposing the charged member creating a second electrostatic image, developing the second electrostatic image by the application of toner of a second color to the exposed areas. The process can be repeated for any number of colors. The multicolor image is then transferred in a single step to a receiving sheet. The second and subsequent development steps are carried out by a magnetic brush developing device (42, 44) employing hard magnetic carrier particles that are tumbled through a development zone which tumbling does not adversely affect the prior toner images. Preferably the hard magnetic carrier particles have a coercivity of at least 100 gauss when magnetically saturated, but more preferably a coercivity of at least 1000 gauss when magnetically saturated. Two multicolor images so formed are transferred to opposite sides of a copy sheet and the images fused simultaneously to provide duplex multicolor images.
IPC 1-7
IPC 8 full level
G03G 13/01 (2006.01); G03G 13/09 (2006.01); G03G 15/01 (2006.01); G03G 15/06 (2006.01); G03G 15/23 (2006.01)
CPC (source: EP US)
G03G 13/013 (2013.01 - EP US); G03G 13/09 (2013.01 - EP); G03G 15/234 (2013.01 - EP); G03G 2215/0174 (2013.01 - EP)
Designated contracting state (EPC)
DE FR GB IT NL
DOCDB simple family (publication)
WO 9001730 A1 19900222; DE 68912299 D1 19940224; DE 68912299 T2 19940707; EP 0381751 A1 19900816; EP 0381751 B1 19940112; JP H03500937 A 19910228
DOCDB simple family (application)
US 8903400 W 19890809; DE 68912299 T 19890809; EP 89910393 A 19890809; JP 50967289 A 19890809