Field control development of electrostatic images

Abstract

Abstract FOR DEVELOPING LATENT ELECTROSTATIC IMAGES ON PAPER SHEETS THERE IS PROVIDED A DEVELOPING STATION WHICH INCLUDES A TANK FOR HOLDING A BATH OF LIQUID DEVELOPER INCLUDING AN INSULATING CARRIER LIQUID WITH PIGMENT PARTICLES DISPERSED THEREIN, AND A RESTRICTED GUIDEWAY OR CHANNEL FOR LEADING THE SHEETS DOWN INTO AND UP OUT OF THE BATH. THE UPPER MEMBER, AT LEAST, OF THE GUIDEWAY IS OF CONDUCTIVE MATERIAL AND PROVIDES A FIELD CONTROL EFFECT FOR INTENSIFYING THE DEPOSIT OF PIGMENT PARTICLES IN THE IMAGE AREAS. THE FIELD CONTROL MEMBER MUST BE PLACED CLOSE TO BUT OUT OF CONTACT WITH THE IMAGED SHEET SURFACE IN ORDER TO HAVE THE DESIRED FIELD CONTROL EFFECT. IN ORDER TO REPLACE THE LIQUID DEVELOPER IN THIS RESTRICTED CHANNEL RAPIDLY ENOUGH TO PREVENT ITS BEING STRIPPED OF PIGMENT PARTICLES, THE FIELD CONTROL MEMBER IS PROVIDED WITH OPENINGS THROUGH WHICH FRESH LIQUID DEVELOPER CAN BE RAPIDLY INTRODUCED INTO THE CHANNEL, AND SPRAY MEANS AND BAFFLES ARE ARRANGED TO EFFECT THIS DEVELOPER REPLACEMENT AS EFFICIENTLY AND RAPIDLY AS POSSIBLE. MOREOVER, THE ARRANGEMENT IS SUCH THAT HYDRODYNAMIC FORCES ARE ALSO GENERATED IN THE LIQUID DEVELOPER IN THE CHANNEL TO MAINTAIN THE SHEET AGAINST A GUIDING SURFACE AND HENCE AT AN ACCURATE SPACING FROM THE FIELD CONTROL MEMBER.

Inventors

• 👤 J Kolibas

Bibliographic Details