Patent ID: 7147990
Filing Date: 2006-12-12
Classification: G03F,H05K

Abstract:
1. A photographic engraving process to provide an engraving with high definition on a contoured metal surface, comprising the steps of: obtaining a photographic positive or negative of the image to be reproduced in the engraving; cleaning, degreasing, and polishing the metal surface where the engraving is to be made; impregnating said metal surface with photosensitive emulsion; making contact between said surface to be engraved and said photographic positive or negative, using a press in which exposing radiation passes through a pressure-applying medium which deforms to adapt to the contours of said emulsion-bearing surface; exposing said surface to actinic light through the photographic positive or negative and said pressure-applying medium; developing said emulsion; attacking the metal surface with salts or acids on the areas unprotected by emulsion; stripping said protective emulsion and cleaning the remains of said salts or acids; and applying a protective layer of transparent enamel.