Liquid development means for electrostatic copiers

Abstract

Abstract A PHOTOCOPIER OF THE ELECTROSTATIC TYPE INCLUDES A DEVELOPING STATION FOR DEVELOPING LATENT ELECTROSTATIC IMAGES ON PHOTOCONDUCTIVE SHEETS. THE DEVELOPING STATION PROVIDES A TANK IN WHICH IS HELD A BATH OF LIQUID DEVELOPER COMPRISING A VOLATILE INSULATING CARRIER LIQUID IN WHICH ARE DISPERSED FINELY DIVIDED PIGMENT PARTICLES WHICH ARE ATTRACTED TO THE IMAGE AREAS ON THE SHEET. THE SHEET IS FED AND GUIDED IN SUCH A WAY AS TO MOVE FACE UPWARD, DIPPING DOWN INTO THE BATH AND THEN COMING UP OUT OF THE BATH, WHEREUPON IT PASSES INTO THE NIP OF A PAIR OF SQUEEGEE ROLLERS WHICH REMOVE EXCESS CARRIER LIQUID. THE SQUEEGEE ROLLER WHICH CONTACTS TE UNIMAGED SURFACE OF THE SHEET HAS A SURFACE OF FRICTIONAL MATERAL, SUCH AS RUBBER, AND THE OTHER SQUEEGEE ROLLER IS OF HARD MATERIAL, SUCH AS CHROMED STEEL. THE LATTER RUNS IN PRESSURE CONTACT WITH A WIPER PAD TO PREVENT RETURN OF ANY ACCUMULATED PIGMENT TO THE FACE OF THE SHEET. A HEATER ADJACENT THE SQUEEGEE ROLLERS REMOVES MOST OF TE BALANCE OF TE CARRIER LIQUID SO THAT THE SHEET IS PRESENTED TO THE OPERATOR IN DRY CONDITION.

Inventors

• 👤 James A Kolibas

Bibliographic Details