Method of producing etched printing plates

Claim 1

A PROCESS OF MAKING AN ETCHED PRINTINNG PLATE FROM A DRY-STRIPPING FILM HAVING A GELATINO SILVER HALIDE EMULSION LAYER CARRIED BY A THIIN HYDROPHOBIC CELLULOSE DERIVATIVE SUPPORT WHICH IS ADHESIVELY JOINED TO A TEMPORARY SUPPORT BY A DRYSTRIPPPING LAYER, COMPRISING EXPOSING THE EMULSION LAYER SEPARATELY THROUGH A SCREEN AND TO A PHOTOGRAPHIC PICTURE, DEVELOPING THE EXPOSED FILM IN A HARDENING DEVELOPER, FIXING AND DEVELOPEN FILM, BLEACHING THE RESULTING FILM WITH AN AQUEOUS SOLUTION CONTAINING A WATER-SOLUBLE ALKALI METAL SALT OF AN ACID WHICH FORMS AN INSOLUBLE SILVER SALT IMAGE READILY SOLUBLE IN THIOSULFATE SOLUTIONS, DRYING THE BLEACH FILM, PRESSING THE BLEACHED GELATIN SILVER SALT LAYER INTO CONTACT WITH THE WET SURFACE OF A METAL PRINTING MEMBER, STRIPPING THE TEMPORARY SUPPORT FROM THE REMAINING SUPPORT, DISSOLVING THE LATTER SUPPORT, WASHING THE UNHARDENED GELATIN FROM THE GELATIN LAYER WHEREBY A RELIEF IMAGE IS FORMED AND TREATING THE RELIEF IMAGE WITH AN ACID ETCHING SOLUTION WHEREBY AN IMAGE IS ETCHED INTO THE SURFACE OF SAID PRINTING MEMBER.