Etching

From Encyclopedia Jr, free information reference for Kids

This page discusses etching in connection with printing and art. For other industrial uses of etching see Chemical etching. For the history of etching, see old master prints. In the United States, the term etching is sometimes used improperly to refer to line drawings done in pen and ink and other media.

Etching is an intaglio method of printmaking in which the image is etched into the surface of a metal plate by acid.

Examples of etching techniques
etching
aquatint
Vernis-Mous or soft ground

[edit] Explanation

In pure etching, a metal (usually copper, zinc or steel) plate is covered with a waxy ground. The artist then scratches off the ground with a pointed etching needle where he wants a line to appear in the finished piece, so exposing the bare metal. The plate is then dipped in a bath of acid, or has acid washed over it. The acid "bites" into the metal, where it is exposed, leaving behind lines to the plate. The remaining ground is then cleaned off the plate. The plate is inked all over, and then the ink wiped off the surface, leaving only the ink in the etched lines. The plate is then put through a high-pressure printing-press together with a sheet of paper (often moistened to soften it). The paper picks up the ink from the etched lines, making a print. The process can be repeated many times; typically several hundred impressions (copies) could be printed before the plate shows much sign of wear. The work on the plate can also be added to by repeating the whole process; this creates an etching which exists in more than one state.

[edit] History

[edit] Origin

The process is believed to have been invented by Daniel Hopfer (circa 1470-1536) of Augsburg, Germany, who decorated armour in this way, and applied the method to printmaking, using steel plates. The switch to copper plates was probably made in Italy, and thereafter etching soon came to challenge engraving as the most popular medium for artists in printmaking. Its great advantage was that, unlike engraving which requires special skill in metalworking, etching is relatively easy to learn for an artist trained in drawing.

[edit] Callot's Technical innovations: échoppe, new hard ground, stopping-out

Jacques Callot (1592-1635) from Nancy in Lorraine (now part of France) made important technical advances in etching technique. He developed the échoppe, an type of etching-needle with a slanting oval section at the end, which enabled etchers to create a swelling line, as engravers were able to do.

He also seems to have been responsible for an improved, harder, recipe for the etching ground, using lute -makers varnish rather than a wax-based formula. This enabled lines to be more deeply bitten, prolonging the life of the plate in printing, and also greatly reducing the risk of "foul-biting", where acid gets through the ground to the plate where it is not intended to, producing spots or blotches on the image. Previously the risk of foul-biting had always been at the back of an etcher's mind, preventing him from investing too much time on a single plate that risked being ruined in the biting process. Now etchers could do the highly detailed work that was previously the monopoly of engravers, and Callot.

He also made more extensive and sophisticated use of multiple "stoppings-out" than previous etchers had done. This is the technique of letting the acid bite lightly over the whole plate, then stopping-out those parts of the work which the artist wishes to keep light in tone by covering them with ground before bathing the plate in acid again. He achieved unprecedented subtlety in effects of distance and light and shade by careful control of this process. Most of his prints were relatively small - up to about six inches or 15 cm on their longest dimension, but packed with detail.

One of his followers, the Parisian Abraham Bosse spread Callot's innovations all over Europe with the first published manual of etching, which was translated into Italian, Dutch, German and English.

[edit] Industrial uses

Etching is also used in the manufacturing of printed circuit boards and semiconductor devices and the preparation of metallic specimens for microscopic observation.

[edit] Controlling the acid's effects

[edit] Hard grounds

There are many ways for the printmaker to control the acid's effects. Most typically, the surface of the plate is covered in a hard, waxy 'ground' that resists acid. The printmaker then scratches through the ground with a sharp point, exposing lines of metal that are attacked by the acid

[edit] Aquatint

Aquatint is a variation in which particulate resin is evenly distributed on the plate, then heated to form a screen ground of uniform but less than perfect density. After etching, the result is a uniformly roughened (i.e., darkened) plate that may then be drawn on by smoothing it, creating the image from dark-to-light rather than the reverse.MMG1

[edit] Printing

Printing the plate is done by covering the surface with ink, then rubbing the ink off the surface with tarlatan cloth or newsprint, leaving ink in the roughened areas and lines. Damp paper is placed on the plate, and both are run through a printing press; the pressure forces the paper into contact with the ink, transferring the image (c.f., chine-collé). Unfortunately, the pressure also subtly degrades the image in the plate, smoothing the roughened areas and closing the lines; a copper plate is good for, at most, a few hundred printings of a strongly etched imaged before the degradation is considered too great by the artist. At that point, the artist can manually restore the plate by re-etching it, essentially putting ground back on and retracing their lines; alternately, plates can be electro-plated before printing with a harder metal to preserve the surface. Zinc is also used, because as a softer metal, etching times are shorter; however, that softness also leads to faster degradation of the image in the press.

[edit] Faults

Faux-bite or "over-biting" is common in etching, and is the effect of minuscule amounts of acid leaking through the ground to create minor pitting and burning on the surface. This incidental roughening may be removed by smoothing and polishing the surface, but artists often leave faux-bite, or deliberately court it by handling the plate roughly, because it is viewed as a desirable mark of the process.

[edit] Trivia

The phrase "Want to come up and see my etchings?" is a romantic cliché in which a man entices a woman to come back to his place with an offer to look at something artistic.

[edit] External links

• Museum of Modern Art information on printing techniques and examples of prints

• Custom Worlwide Etching Service