Developing electrostatic images with a liquid developer

Claim 1

A PROCESS FOR DEVELOPING AN ELECTROSTATIC IMAGE ON THE SURFACE OF A SHEET OF MATERIAL COMPRISING PROVIDING A LIQUID WETTING DEVELOPER DISPENSER CARRYING A SUPPLY OF LIQUID WETTING DEVELOPER AND INCLUDING A THIN ELONGATED DISCHARGE DUCT DEFINED BETWEEN A PAIR OF SPACED BOUNDARY SURFACES AT LEAST ONE OF WHICH IS RIGID AND WHEREIN LIQUID WETTING DEVELOPER IS PREVENTING BY SURFACE TENSION FROM RUNNING OUT THROUGH SAID DUCT EXCEPT WHEN SAID DUCT IS ADJACENT AN ELECTROSTATIC FIELD, PASSING A SHEET OF MATERIAL IN CONTACT WITH SAID ONE RIGID BOUNDARY SURFACE AND CAUSING LIQUID DEVELOPER TO FLOW ONLY ONTO THOSE PORTIONS OF THE SURFACE OF THE SHEET HAVING ELECTROSTATIC CHARGES THEREON IN A THIN ELONGATED AREA EXTENDING WIDTHWISE OF THE ASSOCIATED SHEET, AND MOVING SAID DISPENSER RELATIVE TO THE SURFACE OF SAID SHEET SO AS TO VERY QUICKLY DEVELOP THE ENTIRE ELECTROSTATIC IMAGE ON SAID SHEET.