Everything You Need to Know About Etching
Etching is a decorative and printmarking technique which, like engraving, uses the intaglio technique. “Intaglio” means that indents or incisions are made to a plate or a print surface, where ink is subsequently applied and wiped clean.
This technique was initially used in the fourteenth century for decorating metal, but became popular in the early sixteenth century as a printmarking technique.
What is the technique of etching?
In etching incisions are made on a metal plate treated with an acid solution.
The plate is made of copper, or more frequently zinc and is first prepared with an even acid-resistant ground, which acts like a resist and prevents the plate from being corroded.
Afterwards, a draw is made into the ground and the plate is immersed into the acid solution. During this exposure the metal is “bitten” and the drawn lines are incised. The more the plate stays immersed, the deeper the incision will be.
The resist is then removed and this reveals the drawn image, ready to be charged with ink. This one is applied and gently pushed down the sunken lines but removed from the surface.
The plate is finally put on a printing press, which makes a heavy force and allows the ink to be pulled from the lines and be transferred to the paper. For a background effect, sometimes the ink is not completely removed from the plate surface.
Since etching became popular, other similar techniques were developed. Nowadays they are used in conjunction, in order to get more decorative effects. Let’s sum them up briefly:
• Soft-ground etching: this technique uses a non-drying resist to produce finer lines;
• Spit bite: in this one the plate is treated with painting or splashing acid;
• Open bite: some portions of the plate are exposed to the acid without the resist;
• Photo-etching (or heliogravure, or photogravure): in this technique the metal plate is first coated with a light sensitive ground and then exposed to light in order to produce photographic effects.