EP 0399478 A3 19911204 - METHOD AND APPARATUS FOR IMPROVING A MULTI-COLOR ELECTROPHOTOGRAPHIC IMAGE BY BUFFING

Title (en)

METHOD AND APPARATUS FOR IMPROVING A MULTI-COLOR ELECTROPHOTOGRAPHIC IMAGE BY BUFFING

Publication

EP 0399478 A3 19911204 (EN)

Application

EP 90109729 A 19900522

Priority

US 35810189 A 19890526
US 35891689 A 19890526
US 35891889 A 19890526

Abstract (en)

[origin: EP0399478A2] An improvement in the method and apparatus for producing a multi-color electrophotographic image wherein an electrophotographic medium (16) is mounted on a carrier (12) therefor and is translated over a predetermined path (14) so that the medium (16) is first charged, then exposed to a first light-borne image and then toned. Thus, the unexposed portions of the image bearing charged region of the medium (16) are toned, preferably by a liquid toner, to produce a first color visiblc image. The carrier (12) is then returned to the first position to repeat the foregoing steps to charge the medium and to expose it to a second light-borne image and to tone the second image with a second toning element to produce a second color visible image on the same sheet of medium (16). The improvement comprises means (31) for buffing the surface of the first toned image with a relatively coarse, stiff, and rough fibrous brush member after the first toning step and prior to the second charging step to smooth the previously toned image to prevent color contamination by subsequent imaging cycles. One of the images formed is a cyan image formed with an improved self-fixing, liquid electrographic developer comprising a volatile, electrically insulating liquid carrier and, dispersed in said carrier, (i) toner particles comprising a polymeric binder, cyan pigment and a dispersing agent whereby the cyan image does not flake off or smear during the buffing step.

IPC 1-7

G03G 15/01; G03G 13/01

IPC 8 full level

G03G 13/01 (2006.01); G03G 15/01 (2006.01)

CPC (source: EP)

G03G 13/01 (2013.01); G03G 15/0157 (2013.01); G03G 15/0163 (2013.01)

Citation (search report)

[AD] US 4660503 A 19870428 - JONES ROBERT S [US]
[A] US 3467468 A 19690916 - JOHNSON SIGURD W
[AD] US 4659640 A 19870421 - SANTILLI DOMENIC [US]

Designated contracting state (EPC)

AT BE CH DE DK ES FR GB GR IT LI LU NL SE

DOCDB simple family (publication)

EP 0399478 A2 19901128; EP 0399478 A3 19911204; EP 0399478 B1 19940413

DOCDB simple family (application)

EP 90109729 A 19900522