An intaglio process in which an image is cut through an acid-resistant ground applied to a metal plate Acid is used to bite this image into the plate top
In photoengraving, to produce an image on a plate by chemical or electrolytic action In offset-lithography, an acidified gum solution used to desensitize the nonprinting areas of the plate; also, an acid solution added to the fountain water to help keep nonprinting areas of the plate free of ink