A LA POUPEE
Way of applying colour ink to an etching plate in separate areas as opposed to using separate individually coloured plates. Ink is added to individual lies and area using scrim folded to a point. Form the French for dolly - Poupee
Acid is used at many stages of printmaking, in  particular for cleaning metal plates, for etching,  for preparation of lithographic stones (nitric acid)  and zinc plates (phosphoric acid).  See: acidic cleaning, corrosive agents, engraving, etching, lithography.
ACID FREE
Term used to describe paper, mounting card and tape used for prints to prevent discolouring over time (archival). PH7.0 is neutral on a scale of 1-14 see paper
A process of intaglio engraving on metal. The plate is covered with a special ground made  from a powdered substance through which the  surface is bitten. The resulting effect is not of an  engraved line, but of finely textured rings set  close together. Gradated shades can be obtained  between light grey and black, of varying colour  tones if printed in colour. Consequently, it can  produce a reasonably close representation of a  wash drawing and was originally called an  engraving in the Wash manner (Fr. “gravure en  maniere de lavis”). It can be distinguished from a  brush etching (Fr. “grafvure au lavis”) by the  effects of the aquatint ground: the surface is  indented with small dots which retain the ink,  whereas the surface of a brush etching possesses  an even matt appearance, since it is produced  with acid alone. This distinction is disregarded by  the French. The ground is traditionally obtained  by shaking powdered resin or bitumen over the  plate and fixing it with the application of heat.  The grounded plate is then placed in a bath containing nitric acid, or an acid made from ferric chloride, which bites the areas surrounding the particles of resin. The plate can also be grounded by dotting particles of resin over the surface. Aquatint plates are more fragile than those which have been line engraved, owing to the shallow nature of their indentations. Nevertheless the prints are pulled from the same press.
See: History of aquatint, bitumen, brush etching, dot work, dust-box, grounds, intaglio
ARTIST’S PROOF (A/P)
Part of the print run reserved for the artist taken out of the numbered limited edition. Can comprise 10% of the edition. Often can be differently coloured or experimentally printed.
BATH
A term applied to the acid container used in the etching process, or the liquid container used in electroplating. It is also the receptacle used to dampen paper.
See: biting,
BED (OF PRESS).
Part of the press on which the plate or block rests during printing. In a lithographic press, the bed is a mobile element which transports the stone to a position beneath the scraper. The bed of the press is usually a flat sheet of copper at least 10mm thick although modern table presses use a hardened formica bed and it is possible to use sheets of slate. On an etching press the bed carries the plate covered with dampened paper and blankets between the rollers.
See:Etching, lithography, press
.
BITE
Biting. The process of (1) corroding a design on a metal plate in either intaglio (e.g. etching) or
relief (e.g. line block); and (2) fixing the image on the stone or metal plate in lithography (see : rein-
forcing). It is done with a mordant: acid solution, salt (perchloride of iron), etc.
See: Corrosive agents , Acids, mordlant. See foul bite
BLANKETS
Two to three layers of thin wool blankets are used between the roller of the etching press and the dampened paper over the plate. The blankets spread the pressure of the press and help push the paper into the fine lines of the copper plate.
BON A TIRER (BAT)
Good to print: finished state of the plate or matrix prior to editioning.
BURIN
A small hand tool, consisting of a few inches of steel rod, square or lozenge-shaped in section. The cutting point is formed by sharpening one end to an oblique section; a wooden handle, generally half-round, fits over the opposite end. It is also known as a ‘graver’ and is the principal tool employed by the line-engraver.
BURNISHING
The rubbing down of the plate with a hard, polished, slightly flattened point to soften or moderate tonal areas and lighten unwanted lines or foul biting.
COLLAGRAPH
Collagraphy (sometimes spelled collography) is a printmaking process in which materials are applied to a rigid substrate (such as paperboard or wood). The word is derived from the Greek word koll or kolla, meaning glue and graph, meaning the activity of drawing.
The plate can be intaglio-inked, inked with a roller or paintbrush, or some combination thereof. Ink or pigment is applied to the resulting collage, and the board is used to print onto paper or another material using either a printing press or various hand tools. The resulting print is termed a collagraph. Substances such as carborundum, acrylic texture mediums, sandpapers, bubble wrap, string, cut card, leaves and grasses can all be used in creating the collagraph plate. In some instances, leaves can be used as a source of pigment by rubbing them onto the surface of the plate.
Different tonal effects and vibrant colours can be achieved with the technique due to the depth of relief and differential inking that results from the collagraph plate's highly textured surface. Collagraphy is a very open printmaking method. Ink may be applied to the upper surfaces of the plate with a brayer for a relief print, or ink may be applied to the entire board and then removed from the upper surfaces but remain in the spaces between objects, resulting in an intaglio print. A combination of both intaglio and relief methods may also be employed. A printing press may or may not be used.
COLLOTYPE
Collotype is a dichromate-based photographic process invented by Alphonse Poitevin in 1856.[1][2] and was used for large volume mechanical printing before the existence of cheaper offset lithography. It can produce results difficult to distinguish from metal-based photographic prints because of its microscopically fine reticulations which comprise the image. Many old postcards are collotypes. While no longer a commercial process, its possibilities for fine art photography were first employed in the United States by Alfred Stieglitz.
The collotype plate is made by coating a plate of glass or metal with a substrate composed of gelatin or other colloid and hardening it. Then it is coated with a thick coat of dichromated gelatine and dried carefully at a controlled temperature (a little over 50 degrees Celsius) so it 'reticulates' or breaks up into a finely grained pattern when washed later in approximately 16 °C water. The plate is then exposed in contact with the negative using an ultraviolet (UV) light source which changes the ability of the exposed gelatine to absorb water later. The plate is developed by carefully washing out the dichromate salt and dried without heat. The plate is left in a cool dry place to cure for 24 hours before using it to print.
To produce prints, the plate is dampened with a glycerine/water mixture which is slightly acidic, then blotted before inking with collotype ink using a leather or velvet roller. A hard finished paper such as Bristol, is then put on top of the plate and covered with a tympan before being printed typically using a hand proof press. Collotypes are printed using less pressure than is used in printing intaglio, or stone lithography. While it is possible to print by hand using a roller or brayer, an acceptable consistency of pressure and even distribution of ink is most effectively achieved using a press.

CORROSIVE AGENTS
Corrosive agents. Products used for cleaning and biting the various fabrics, papers, stones and metals used in printmaking are divided into three types: acids, alkalis and salts. Nitric acid is the most commonly used of the acids. It bites copper (c. 15° Baume), zinc and steel (between 5° and 15° Baume), in a rapid, shallow manner; it is also used for cleaning and for preparing the lithographic stone. Sulphuric acid is used for cleaning and biting steel. Hydrochloric acid attacks zinc and steel and in a diluted form is used for washing. It is also the acid constituent of Dutch Mordant. Phosphoric acid is used for cleaning ferrous metals and aluminium as well as for preparing zinc and aluminium for the lithographic and offset techniques. Hydrofluoric acid attacks glass and ceramic. Acetic acid (vinegar) was formerly used frequently in the composition of etches and can be used to brighten up drawn lines prior to biting. Of the alkalis, soda is the most commonly used: as a detergent for washing the screen, for cleaning metal plates, and for bleaching. It is used particularly on zinc, iron and aluminium, as well as on organic materials. Potash possesses approximately the same characteristics. Ammonia is used as a cleaning agent. The most frequently used of the salts is ferric chloride, a slow etch which penetrates in depth while preserving the form of the design. On account of these qualities it is much used in aquatint and photogravure.
CREVE
A common fault occurring when biting closely drawn lines on a hard ground. The ground is apt. to break down especially in nitric acid at the point where lines converge, or cross, leaving small open corners of exposed surface which
invariably print pale.
DRYPOINT
Drypoint is a printmaking technique of the intaglio family, in which an image is incised into a plate (or "matrix") with a hard-pointed "needle" of sharp metal or diamond point. Traditionally the plate was copper, but now acetate, zinc, or plexiglas/perspex are also commonly used. Unlike engraving where the lines are formed by pushing the burin through the surface of the plate drypoint is more like etching: easier for an artist trained in drawing to master, as the technique of using the needle is closer to using a pencil than the engraver's burin.
The lines produced by printing a drypoint are formed by the burr thrown up at the edge of the incised lines, (similar to the parapet thrown up on the edges of a trench) in addition to the depressions formed in the surface of the plate. A larger burr, formed by a steep angle of the tool, will hold a lot of ink, producing a characteristically soft, dense line that differentiates drypoint from other intaglio methods such as etching
or engraving which produce a smooth, hard-edged line. The size or characteristics of the burr usually depend not on how much pressure is applied, but on the angle of the needle. A perpendicular angle will leave little to no burr, while the smaller the angle gets to either side, the larger the burr pileup. The deepest drypoint lines leave enough burr on either side of them that they prevent the paper from pushing down into the center of the stroke, creating a feathery black line with a fine, white center. A lighter line may have no burr at all, creating a very fine line in the final print by holding very little ink. This technique is different from engraving, in which the incisions are made by removing metal to form depressions in the plate surface which hold ink, although the two methods can easily be combined, as Rembrandt often did. Because the pressure of printing quickly destroys the burr, drypoint is useful only for comparatively small editions; as few as ten or twenty impressions with burr can be made, and after the burr has gone, the comparatively shallow lines will wear out relatively quickly. Most impressions of Rembrandt prints on which drypoint was used show no burr, and often the drypoint lines are very weak, leaving the etched portions still strong. To counter this and allow for longer print runs, electroplating (called steelfacing by printmakers) can harden the surface of a plate and allow the same edition size as produced by etchings and engravings.
A solution of hydrochloric acid and potassium chlorate, used mainly for etching fine work on copper
ECHOPPE
An etching-needle with a point ground to an oval section. Frequently employed by early etchers, such as Callot, to imitate on a hard ground the swelling line made by a burin.
ENGRAVING
Engraving covers all works of art or industry (both plate and impresssion) which use incision as means of marking the design. In printmaking, more specific meanings must be applied to avoid confusion. Manual engravings (e.g. burin engravings) can be differentiated from mechanical, semi—mechanical, photomechanical, photochemical, electrochemical and, today, electronic engravings.
Distinctions must also be applied to relief and intaglio engravings (the former are more usually called “cuts”, except in the case of wood engravings), as well as to the type of material used: copper, zinc, aluminium, stone, glass, etc. Where the incisions are made chemically (i.e. with acid) the term “etching” should, strictly speaking, be adhered to.
See: burin engraving.
Engraving :
Artist’s engraving (or etching). One which has been made by the artist of the original design as opposed to being reproduced or interpreted by a craftsman. The French term “peintre-graveur” applies to a painter who engraves or etches his own work, i.e. an artist engraver,artist etcher or artist printmaker
See: free engraving.
Engraving “en bois mat et de relief”. A French term applied to an old type of woodcut used for printing large lettering on posters, chiaroscuro prints and painted canvases.
Engraving with sand. Metal (usually zinc) may be engraved by blasting it with sand, using a stencil as a guide.
Reproductive engraving. The reproduction of an original drawing or painting, through the means of an engraving made by a craftsman rather than the artist himself.
See: facsimile, interpretative print.
One of the most important methods of intaglio engraving. It consists in laying an acid-resistant ground over a metal plate (copper is the best, Zinc is also used) on the surface of which the design is drawn so as to expose the metal. The plate is then bitten with a mordant, usually nitric acid (hence the term “eau-forte” in French),which incises the lines so that the plate can be inked and printed as an ordinary intaglio engraving.
The distinguishing characteristic of the technique is that it allows the designer much greater freedom of expression than other methods of intaglio engraving, since the laborious task of incising the plate manually is dispensed with. It has therefore been the preferred medium of artists who are primarily painters or draughtsmen. It does, however, require a certain technical experience to achieve good results, particularly in laying the ground and biting the plate.
An etching is executed in five stages:
(1) The plate is polished and cleaned with chalk or whitening to ensure that the ground adheres well.
(2) Laying the ground: either a ball of solid ground is melted over the plate, or a cold liquid ground is used. The former remains soft for a longer period, the latter dries rapidly and must consequently be worked more quickly than a hard ground. Different grounds are used for reworking the plate.
(3) The design is cut through the ground with an etching needle; the lines must remain separate in order to avoid foul-biting.
(4) The plate is then bitten (or “etched”) either by placing it in an acid bath or by covering it with the mordant.
(5) The ground is removed before the plate is inked and put through the press like an ordinary intaglio engraving. The etching process is an inherent part of various other techniques, e.g. aquatint, brush etching, soft-ground etching, sugar-lift process, etc. lt can also be combined with burin engraving and drypoint where the etched part of the design is done first.
See: biting, grounds and varnishes, impression, intaglio, techniques.
The etching process must not be confused with the “ etch” used in lithography: this is a gum acid solution applied to the stone (already drawn and prepared with a resist) with the aim of reinforcing the image.
See: reinforcing (the lithographic image).
Lightly etched (plate). One which has been etched for a short period. An impression taken from such a plate is light in tone. A ‘light etch” refers to a weak acid or any diluted mordant.
Etching a la plume”. A method of intaglio printing in which a pen and ink drawing is made on a clean metal plate. When this has dried, the entire surface is covered with a light aquatint ground and placed in an acid bath Which has the effect of removing the ground Where it is to be found over the ink. The plate can then be bitten as for a normal etching. The technique is difficult to do Well, and was much improved by the sugar-lift process.
Also referred to as perchloride of iron this is actually a salt which corrodes zinc or copper plates
FOUL BITE
Unwanted lines or marks bitten into the metal plate where acid has managed to permeate the resist. Can be the result of an insufficiently well degreased plate, ground that has been scorched during smoking or even wear from the action of the hand during drawing.
IMPRESSION
The resultant print from a plate or stone after passing through the press
INTAGLIO
Printing from an etched or engraved plate where the ink is pulled out of the recessed lines. One of the four (five if you count digital prints) categories of printmaking: Intaglio, Relief, Planographic and Stencil.
INTAGLIO PRINT
Print from an etched or engraved plate where the ink is pulled out of the recessed lines as opposed to off the surface (relief)
Finite number of identical prints,each numbered as part of the total. A print numbered 13/50 for example, denotes that this is the thirteenth print in an edition of Fifty identical impressions.See Editioning Conventions
LITHOGRAPHY
Form of printing using a limestone block or lightly etched plate. Works on the principle of oil and water repelling each other
MATRIX
Printing block, screen or plate from which the image is printed. The object on which the original print is created as opposed to reproduced from an existing image.
MEZZOTINT
Essentially a tonal method, in which the surface of a metal plate is systematically roughened into a mass of close cut, regular indentations. For this, a serrated steel tool known as a ‘rocker’ is usually employed. When printed, the textured ground reads as a uniform dark; lights are then obtained by
scraping and burnishing into the ground - working from dark to light, the reverse of etching and engraving. The term ‘mezzotint’ applies also to the printed impression
MULLER
A fairly heavy knob of stone (usually marble) or glass, the base of which is flat or slightly convex, and often slightly roughened; used for crushing dry pigment and grinding it with plate oil into a suitable consistency for intaglio printing
.
NUMBERING
OFFSET LITHOGRAPHY
Modern lithographic process in which the plate is printed on to a rubber roller which transfers the image onto the paper. The obvious advantage being that the image is the same way round as on the plate and not a mirror image
PHOTOGRAVURE
Photogravure is an intaglio printmaking or photo-mechanical process whereby a copper plate is coated with a light-sensitive gelatin tissue which had been exposed to a film positive, and then etched, resulting in a high quality intaglio print that can reproduce the detail and continuous tones of a photograph.
PLANOGRAPHIC
A planographic print is one whose image is printed off a flat surface of a stone or plate. Applies mainly to Lithographs
See also Stencil, relief, and intaglio
PLATE
A (metal plate is a flat sheet of metal, usually copper, steel or zinc, used as a matrix for a print. Metal plates are used for intaglio prints and for some lithographs
PLATEMARK
The platemark is the rectangular indentation in the paper of the intaglio print caused by the edge of the plate. Unlike other forms of prints the paper in an intaglio print is forced down and around the plate under considerable pressure when pulled through the press. Some reproduction are given a false platemark.
PROOF
Impression or print pulled prior to the final regular edition. A trial or working proof is a print taken so the artist can gauge the progress of work on the matrix and decide whether to continue or decide that it is ready to edition or Bon a tirer. Proofs showing the progress of work are know n as states.
RELIEF ETCHING
Etching a plate in such a way that only the drawn or positive image stands out in relief: the rest of the plate surface the negative area is bitten down. With a straightforward black and white relief print, the raised surface of the plate would normally be inked with a roller, and the intaglio areas would be left to print white
RELIEF PRINT
Relief. As opposed to intaglio and planographic printing, the black areas of an impression taken from a block cut in relief are made by inking the raised parts, thereby leaving the furrows to print white.
See: letterpress.
REPOUSSAGE
Forcing up the depressed surface of a deeply etched or scraped area in a metal plate to its original level, either by hammering the back of the plate, or by pressing it up on a printing-press.
RETROUSSAGE
Increasing the richness and density of an intaglio print by drawing the ink fractionally out of the lines, pits and hollows of an otherwise normally inked and cleanly wiped plate. The most effective way to achieve this is to trail, briefly and gently, a soft muslin over the inked intaglio work.
SCREEN-PRINTING
An ancient method of oriental printmaking which, considerably modified and ameliorated, has become one of the four most important methods of modern printing. Contemporary artists have made much use of it as a printmaking technique. The principle of screenprinting consists in applying stencils to a screen (constructed of silk or of some synthetic or metallic material), in such a way that when ink is applied it is prevented from passing through some parts while penetrating the rest of the screen, thereby printing an image on paper placed underneath. The screen is stretched across a frame and attached to a base in such a manner that it can readily move up and down, so that paper can be easily placed and removed as required. For each impression, the paper is placed against registration tabs to ensure that the printing is done in the correct position. The ink is poured over the masking at one end of the screen and when this has been lowered into position, the ink is scraped across the screen with the aid of a squeegee. The most important part of the process is the preparation of the screen. Stencils may be applied in a variety of ways,
including the use of filling-in liquid, varnish or plastic film. A drawing can be made directly on the surface with a special ink which is removed in readiness for printing after the rest of the screen has been blocked out. A photographic stencil is made by initially sensitizing the screen.
SCRIM
Also called muslin or tarlatan. A stiff loosely woven fabric not unlike net curtains which is used to wipe ink off the surface of the inked etching plate - leaving ink in the lines. see wiping the plate
SIGNING
A signed print is one signed, in pencil or ink, by the artist and/or engraver of the print. A print is said to be signed in the plate if the artist's signature is incorporated into the matrix and so appears as part of the printed image. Proof prints were originally signed as "proof" that the impression met the artist's expectation. Later proof prints were signed in order to add commercial value to these impressions. In the late nineteenth century, in response to the development of photomechanical reproduction techniques, fine arts prints were signed by the artists in order to distinguish between original prints and reproductions. Seymour Haden and James McNeil Whistler are usually credited with introducing this practice in the 1880s.See Editioning Conventions
STATE
State of a print includes all the impressions pulled without any change being made to the matrix. A first state print is one of the first group of impressions pulled. Different states of a print can reflect intentional or accidental changes to the matrix. States of a print should be distinguished form editions of a print.
TYMPAN
In hand-operated letterpress printing, the bruzer tympan is the taut cloth or paper mounted in a frame which is placed over the sheet of paper immediately prior to lowering the platen to make the impression.
Bruzer's Tympan refers to a sheet of oiled manilla paper which was securely fastened to the face of the platen of a letterpress printing machine. Underneath the tympan would be a packing which would vary in grade of firmness relevant to the type or image to be printed. Pre-cut tympan papers were relatively expensive and, as such, were reused depending on their condition and the nature of the work. The under packing consisted of loose fibre paper/board (sometimes known as saffron) which absorbed the impact of the letterpress principle thus avoiding damage to the hand-set or pre-cast typography or engravings.
In etching or engraving the plate ink is pushed in to the lines which requires covering the whole surface of the plate with ink (attempting to ink areas more selectively will result in a patchy plate tone) Wiping is the action of removing ink from the surface of the plate whilst leaving it in the lines. This is done using a folded pad of scrim which is swept across the surface of the plate. Care is needed not to rub the plate as this will drag ink out of the lines. The plate can be finished off by hand wiping the plate with the edge of the hand which will heighten the contrast of the print.
PRINTMAKING: GLOSSARY AND EXPLANATION OF TECHNICAL TERMS
A dictionary or glossary of printmaking terms

COLIN BAILEY
ARTIST & PRINTMAKER
Printmaking Glossary.
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FURTHER READING
With etching having been around for such a ling time  it is not surprising that a good many books have been written on the subject - the best by practicising printmakers.

The Art of Etching by E S Lumsden is the book I used when first learning etching and I still have that original battered and acid stained copy! This is the best technical guide to etching I have found and contains sate by state examples of the author’s own etching as well as a good selection of the best known Etchers
Also worth  buying:
It seems obvious after a just few minutes of reading any page on any technical subject such as printmaking that there are going to be a wealth of unfamiliar terms. Even the most experienced printmaker will find words that are ambiguous or which mean something different in the printmaking context than they do outside it. This list is my first attempt to define and explain in more simple language some of the jargon associated with the various printmaking media.
This is by no means a comprehensive list,; it contains mistakes, omissions and is at the moment a bit clunky. This printmaking glossary is an ongoing project: Where possible I have used my own interpretation of each definition elsewhere I have pulled together definitions from various other sources. I will add a reference list, diagrams and illustrations soon.