The image is developed by corroding a metal plate in a bath with acid or salts. Acid resistant coverings known as grounds are used to protect the areas not to be etched.
Nina Morgan: etching detail
The ground is drawn into with a pointed instrument. After a period in the etchant, the plate is cleaned, and inked up. This is done by pushing ink into the deep etched lines. The surface or relief of the plate is wiped clean The plate is then placed on a press, dampened paper is placed over it and it is run through the press at great pressure. The paper is forced into the etched or incised lines picking up the ink and transferring the image. Prints are often distinguished by a ‘plate mark’, a deep mark at the edge of the printing plate
The variety of materials and techniques that can be applied to etching makes it a very versatile and expressive area of printmaking. The many different ways to manipulate the grounds during the mark-making process , the action and extent of the corrosion and the printing itself all give the artist an infinite range of creative possibilities.
Etching is one of the intaglio group of printmaking terms which covers a range of techniques including hardground, softground, aquatint ,sugarlift and photo-etch.
A hard ground etching is produced by drawing through an acid resistant ground using the usual drawing techniques such as cross-hatching. The drawing is usually done with a sharp tool called an etching needle although anything can be used to draw through the ground. A great variety of line can be achieved by etching some lines for longer periods and holding others back with the use of stop out.
Soft ground is a technique which allows texture to be introduced into an etching.
The plate is covered by a soft ground which is responsive to the impressions of textured materials pressed into it. Where the materials have made an impression the metal is exposed to the effects of the acid and the textures are etched into the surface.
Soft crayon like marks can also be made by placing a sheet of paper over the plate and drawing with a pencil. This removes the ground where pressure is applied with the pencil.
Sugar lift. This enables painterly marks to be achieved on the plate and is usually used in conjunction with aquatint.
Spit bite. A weaker solution of acid is painted directly onto the plate and is useful for producing cloud like textures.
More often than not a few or even all of the above techniques are used on a plate creating endless possibilities.
At SPW we recognise that many of the traditional materials and techniques that characterise printmaking are toxic, both to the environment and to one’s health.
SPW therefore do not use acids for etching metals, but much safer solutions of metal salts. These work by exploiting the natural electro-chemical reaction that occurs between certain metals.
For etching into copper plate we use a solution of Iron Chloride. For etching into zinc or aluminium plate we use a solution of Copper Sulphate and table salt.
In place of traditional grounds we employ techniques and materials pioneered by Edinburgh Printmakers. These are water-based and therefore do not require the use of solvents.
Intaglio: The Complete Safety-first System for Creative Printmaking: Robert Adam & Carol Robertson
Thames and Hudson, 2007 ISBN-13: 978-0-500-51343-9 ISBN-10: 0-500-51343-0
At last the definitive guide to safe and non-toxic printmaking. An essential reference book from the authors of Screenprinting: The Complete Water-based System.
Colour Etching (Printmaking Handbooks): Nigel Oxley
A and C Black, 2007
All the techniques and examples of printing intaglio work in colour. As with all A and C Black's Printmaking Handbooks this is and excellent introduction to the subject.
The Contemporary Printmaker: Intaglio Type and Acrylic Resist Etching: Keith Howard
White-Cross Press, 2003
Their are only two books worth having if you are interested in the art of non-etch intaglio and the use of photopolymer film. This is one of them and a great source of technical information for much, much more.
Non-Toxic Intaglio: Henrik Bøegh
And this is the other one. Available through Intaglio Printmaker, this book gives alternative techniques to the above