Intaglio (from the Italian word “to carve”) is the reverse of relief printing. In a relief print, the ink is rolled onto the surface and not into the lines; in an intaglio print, the ink is pushed into the lines and pits then wiped off the surface of the plate. To pull an intaglio print, the artist must use a printing press in order to create enough pressure to force the dampened printing paper down into the inked lines. The matrix in intaglio is a thin plate of metal (usually zinc or copper), Plexiglas, or any other surface in which a line can be made.
In etching the artist covers the plate with a protective ground, draws through the ground, and then immerses the plate in a mordant (such as nitric acid or ferric chloride.) The mordant eats into the metal wherever it is exposed, creating etched lines and marks that
correspond to the lines drawn through the ground. Using a hard ground yields a crisp line; soft ground creates a less distinct line and can also be employed to transfer textures.
Broad tonal areas can be created with aquatint. The artist either sprays a plate with a fine dusting of paint or melts rosin dust onto the plate. When the plate is immersed in the mordant, the mordant bites around the paint or rosin particles, creating a textured surface on the plate that will hold ink and print as a tonal area.
In dry point lines are created without the use of a mordant. The artist draws with a sharp needle directly into the surface, creating a shallow line with a ridge of metal or Plexiglas on one side. This ridge, called the burr, is the metal or plexi that is displaced as the line is drawn (similar to the ridge of soil thrown up by a plow.). The burr catches more ink than the shallow line beside it and prints as a velvety dark.
The metal engraver uses a tool called a burin to carve lines into the metal plate. The engraved line is sharper, with a cleaner edge, than other intaglio lines.
In mezzotint, the artist first uses a tool called a rocker to cover the surface of the plate with a uniform texture of pits and burrs. A print pulled at this point would be solid black. To create an image the artist scrapes, burnishes, and smooths the roughened metal, creating areas that will not catch ink and that will print as lighter tones. The mezzotint artist creates a white image on a dark ground.
Solarplate is a thin plate covered with a light-sensitive emulsion. To create a solarplate etching, a drawing or other image printed on clear acetate is set on top of the plate, which is then exposed to light. Light hardens any uncovered area of the plate, but the emulsion can be washed out of the lines and other areas covered by the drawing. This results in lines that can be printed as an intaglio.
Color intaglio prints are usually created with multiple plates, in much the same way that multiple blocks are used to create color woodcuts.