Method for making printing forms and molds

Claim 1

IN A PHOTOMECHANICAL METHOD FOR PREPARING PRINTING FORMS AND MOLDS HAVING CONICAL PRINTING ELEMENTS BY EXPOSING TO LIGHT A BODY OF POLYAMIDE POLYMER LIGHT SENSITIZED WITH A LIGHT-SENSITIVE HARDENING AGENT FOR SAID POLYMER, WHEREBY THOSE PORTIONS OF THE POLYAMIDE BODY EXPOSED TO LIGHT ARE HARDENED, AND SUBSEQUENTLY DEVELOPING SAID POLYAMIDE BODY BY REPEATEDLY SOFTENING AND ABRADING UNHARDENED SURFACE PORTIONS OF THE POLYAMIDE BODY WHILE MOISTENING SAID BODY WITH A SOFTENING AGENT FOR SAID POLYAMIDE, WHEREBY UNHARDENED PORTIONS OF SID BODY ARE PARTIALLY REMOVED TO LEAVE CONICAL PRINTING ELEMENTS COMPRISING EXPOSED AND HARDENED PORTIONS AND UNREMOVED UNHARDENED PORTIONS, THE IMPROVEMENT OF REPEATEDLY SOFTENING AND ABRADING UNHARDENED SURFACE PORTIONS OF THE POLYAMIDE BODY BY FRICTIONALLY CONTACTING THE BODY DIRECTLY WITH THE SURFACE OF A PLIABLE PRESSURE-EQUALIZING CUSION MOISTENED WITH SID SOFTENING AGENT, SAID CUSHION CONSISTING ESSENTIALLY OF A GAS-FILLED THIN-WALLED BODY MADE FROM THIN SHEETS OF A PLIABLE MATERIAL.