Method for making vectographs

Claim 1

THE PROCESS WHICH COMPRISES FIRST APPLYING TO A SIDE OF A MOISTURE SENSITIVE BIREFRINGENT MOLECULARLY ORIENTED FILM AN AQUEOUS SENSITIZING SOLUTION CONTAINING A LIGHT SENSITIVE DICHROMATE HARDENING AGENT AND A COPPER COMPOUND STAIN RELEASING AGENT AND ALLOWING SAID FILM TO ABSORB AN APPRECIABLE AMOUNT OF SAID SENSITIZING SOLUTION, THEREAFTER EXPOSING DIFFERENT AREAS OF SAID SIDE OF SAID FILM TO DIFFERENTIAL AMOUNTS OF LIGHT TO RENDER RESPECTIVE AREAS THEREOF RECEIVING GREATER AMOUNTS OF LIGHT MORE HARDENED AND CORRESPONDINGLY LESS ABSORBENT TO AN AQUEOUS DEVELOPING SOLUTION CONSISTING ESSENTIALLY OF AN IODIDE STAINING AGENT HAVING AN IODINE STAIN THEREIN AND A REDUCING AGENT PREVENTING SAID STAIN FROM FORMING IN SAID DEVELOPING SOLUTION, NEXT APPLYING SAID DEVELOPING SOLUTION TO SAID EXPOSED SIDE OF SAID FILM TO CAUSE ABSORPTION THEREOF INTO SAID EXPOSED AREAS OF SAID FILM, THE ABSORPTION BEING PROPORTIONATELY GREATER IN LESS HARDENED AREAS WHEREBY REACTION OF SAID RELEASING AGENT IN SAID FILM WITH SAID STAINING AGENT ABSORBED THEREIN WILL RELEASE SAID IODINE STAIN FROM SAID STAINING AGENT INTO SAID AREAS OF SAID FIL SAID STAINING AGENT ABSORBED THEREIN WILL RELEASE SAID IODINE STAIN FROM SAID STAINING AGENT INTO SAID AREAS OF SAID FILM SURFACE IN AMOUNTS CORRESPONDING TO RESPECTIVE AMOUNTS OF SAID DEVELOPING SOLUTION ABSORBED INTO SAID AREAS AND SAID RELEASED STAIN WILL BOND WITH THE MOLECULAR STRUCTURE OF SAID FILM, ALLOWING SAID DEVELOPING SOLUTION TO REMAIN ON SAID SIDE OF SAID FILM ONLY UNTIL DESIRED MAXIMUM DENSITIES OF SAID STAIN ARE PRODUCED IN THE LEAST HARDENED AREAS THEREOF AND FINALLY REMOVING REMAINING AMOUNTS OF SAID DEVELOPING SOLUTION.