Processes for making resists

Claim 1

IN A PROCESS FOR MAKING AN ETCHING RESIST FROM AN EXPOSED, DEVELOPED AND FIXED THIN FLEXIBLE PHOTOGRAPHIC FILM HAVING A CELLULOSE NITRATE MEMBRANE AS THE PERMANENT SUPPORT AND A WATER-INSOLUBLE ETHYL CELLULOSE/CELLULOSE NITRATE STRIPPING LAYER ON ITS OUTER SURFACE AND ON ITS OTHER SURFACE IN SEQUENTIAL DIRECT CONTACT A THIN GELATIN SUBSTRATUM, A CONTIGUOUS GELATIN LAYER HAVING A THICKNESS FROM 0.06 TO 0.35 MIL, SAID GELATIN BEING SOLUBLE IN WATER AT 40* C. TO THE EXTENT OF AT LEAST 10% BY WEIGHT AND THEN A HARDENED GELATIN SILVER IMAGE-BEARING LAYER IN CONTACT WITH AN ETCHABLE PRINTING SURFACE, THE IMPROVEMENT WHICH COMPRISES WETTING THE OUTER SURFACE OF THE COMPOSITE MEMBRANE COMPRISING SAID CELLULOSE NITRATE MEMBRANE AND SAID STRIPPING LAYER WITH A WATER-MISCIBLE SOLVENT TAKEN FROM THE GROUP CONSISTING OF ANHYDROUS METHANOL, ANHYDROUS ETHANOL, ETHANOL CONTAINING WATER IN AN AMOUNT UP TO 2% BY WEIGHT, METHANOL CONTAINING WATER IN AN AMOUNT UP TO 5% BY WEIGHT, ANHYDROUS MIXTURES OF 2 TO 3 SOLVENTS TAKEN FROM THE GROUP CONSISTING OF METHANOL, ETHANOL AND ACETONE, AND SUCH MIXTURES CONTAINING WATER IN AN AMOUNT UP TO 5% BY WEIGHT, AND MIXTURES OF METHANOL AND ACETONE CONTAINING 5 TO 10% BY WEIGHT OF WATER, AND WHILE SAID MEMBRANE IS STILL WET WITH THE SOLVENT, REMOVING THE RESULTING POROUS MEMBRANE BY TREATING IT WITH WATER IN THE LIQUID PHASE AT A TEMPERATURE ABOVE 90* F.