Abstract:
THIS A METHOD FOR DEVELOPING ELECTROSTATIC IMAGES ON A MOVING INSULATING SURFACE WITH DEVELOPER MATERIAL IN WHICH THE FLOW OF DEVELOPER MATERIAL MOVES DOWNWARD AND IN A DIRECTION OPPOSITE TO THE MOVEMENT OF THE INSULATING SURFACE AND WHICH CAN BE TERMED COUNTERFLOW CASCADE DEVELOPMENT. THE FLOW OF DEVELOPER MATERIAL IS DIRECTED ONTO THE INSULATING SURFACE SUCH THAT A FINISHING DEVELOPMENT ZONE IS FORMED AT THE POINT OF ENTRY OF THE DEVELOPER MATERIAL TO A POINT UPWARD THEREFROM. IN ADDITION, MEANS HAVING A CONTROLLING FORCE OVER TONER DEPLETED CARRIER PARTICLES IS POSITIONED ADJACENT THE FINISHING DEVELOPMENT ZONE FOR REGULATING SUCH PARTICLES AND THEREBY PREVENTING THEM FROM BEING CARRIED UPWARDLY AND OUT OF THE ZONE.