Copperplate engraving

Intaglio (/ɪnˈtæli.oʊ/ in-TAL-ee-oh; Italian: [inˈtaʎʎo]) is the family of printing and printmaking techniques in which the image is incised into a surface and the incised line or sunken area holds the ink. It is the direct opposite of a relief print.

Normally, copper or zinc plates are used as a surface or matrix, and the incisions are created by etching, engraving, drypoint, aquatint or mezzotint.Collagraphs may also be printed as intaglio plates.

In intaglio printing, the lines to be printed are cut into a metal plate by means either of a cutting tool called a burin, held in the hand – in which case the process is called engraving; or through the corrosive action of acid – in which case the process is known as etching. In etching, for example, the plate is covered in a resin ground or an acid-resistant wax material. Using an etching needle, or a similar tool, the image is engraved into the ground, revealing the plate underneath. The plate is then dipped into acid. The acid bites into the surface of the plate where it was exposed. Biting is a printmaking term to describe the acid's etching, or incising, of the image. After the plate is sufficiently bitten, the plate is removed from the acid bath, and the ground is removed to prepare for the next step in printing.

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