摘要 |
Photographic engraving procedure with high definition on metal, covering the stages of: obtaining a photographic positive or negative of the image to be reproduced in the engraving, cleaning, de-greasing, polishing and shining of the metal surface where the engraving is to be made, impregnation of the surface with photosensitive emulsion, making contact between the photographic positive or negative with the surface to be engraved, using a press, exposure to actinic light, developing of the emulsion, attack of the metal with salts or acids on the areas unprotected by emulsion during the development action, stripping of the protective emulsion and cleaning of the remains of salts or acids, and application of a protective layer of transparent enamel.
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