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Friday, February 20, 2009

Intaglio Printmaking

I have spent many years as a printmaker and for this reason, I am sensitive to the meanings attributed to the word "print." This has been previously discussed in my article Notes from an Opinionated Artist Printmaker
The possibility of scanning and reproducing art in order to make digital prints sometimes causes confusion in the mind
of the public as to what is an original print. Most of my experience has been in the area of intaglio printmaking so the following is my explanation of some of the procedures involved in creating an original print.
It is useful to know how this art form is produced because it increases appreciation of fine art prints that are on exhibit in most art museums. Some of our most revered artists, such as Rembrandt and Picasso have used this medium in the most expressive and adventurous manner.
I have briefly described the essential steps needed to create an original print. This gives some explanations and definitions, but in no way goes into the very complex detail involved in producing contemporary prints.
The term intaglio, (from the Italian itagliare, which means to cut, engrave, carve) is used to designate a number of printmaking processes such as engraving, etching, drypoint, aquatint, soft ground, lift ground, mezzotint, collograph, and other printing techniques in which an incised line, or tonal effect in a plate will hold ink while the surface is wiped clean. Only the line or rough surface will print when dampened paper is placed on a plate and both are run through an etching press with enough pressure to force the paper into the lines and rough surface of the plate. The resulting art image is the original print. The plate that has the image on it is called the matrix.
How the lines and or rough surfaces are created is the difference in the various terms used for this kind of printmaking.
Engraving is created when the line is cut by hand into either a copper or zinc plate using a tool called a burin. Drypoint is created when the line is drawn by hand with a sharp drypoint needle. A burr of metal will be pushed aside on the plate and this will catch the ink and thus make the printed line fuzzy instead of sharp.
In etching, the line is bitten into the plate wherever the artist has drawn through an acid proof ground usually made up of wax, lacquer or asphaltum.
In an aquatint, many tones are bitten into the plate after the surface has been covered with a fine dust of rosin that is carefully heated to cause the rosin to adhere to the plate. An alternative form of causing a tone is to spray a fine spray of lacquer onto the plate. The length of time and frequency of placing the plate into acid will determine the depth of the tone.
Mezzotint is a way of producing a tone using a tool called a mezzotint rocker. This is curved serrated tool that will create many thousands of little indentations on the plate when it is rocked back and forth over a long period of time. It creates a very dark and rich black tone but is very time consuming. It is possible to use this on a section of a plate or on the entire plate. If the plate is covered with the indentations, a artist can use a tool called a burnisher to smooth areas in order to achieve variations in tone.
Soft-ground etching is made when a plate is covered with a ground containing Vaseline. This won't harden so the surface can receive textures that are pressed into the plate.
A lift-ground etching is made by first painting a drawing on a clean plate using a water soluble ink that usually will contain soap. The entire plate is then coated with a thin coating of wax. This is then soaked in water so that the soluble drawing will dissolve and expose the plate where the image has been placed. This is then bitten in acid and printed.
A collagraph is a plate that has been created by making a collage of various materials that have been glued onto a base plate. This might be cardboard or any plastic. The collagraph is inked in the same way as other intaglios. The ink will be held in the recessions and indentations when the plate is printed.
An embossing is created when an intaglio plate is run through a press without ink. Thus the incised lines and surfaces will be raised when the plate is run through a press. This technique is often used in commercial printing of fine invitations.
Contemporary printmakers often use a combination of these processes. The results are unique to this form of printmaking.
The plates used for intaglio are traditionally copper or zinc. Copper is preferred for engraving because the grain of the metal is smooth and it is soft enough so that it is possible to draw into it. It also gives a clean etch when it is placed in acid. Zinc is cheaper and is more brittle for cutting into and gives a rougher bite when it is placed in acid.
Nitric acid is usually used to etch copper or zinc. It is mixed with water in various dilutions to create different effects. Usually four parts water to one part nitric acid will give a deep etch for strong lines. Delicate work such as aquatint might require a dilution of ten parts water to one part nitric. Use of acid requires a great deals of care. It is important to put water into a container first and then add the acid to the water. Care should be taken to use a glass measuring cup and work slowly and carefully whenever handling these materials and always keep acid locked up when not in use. It is also necessary to have a bottle of ammonia handy when using acid in case acid gets splashed on clothing because acid will burn a hole in clothing very quickly. Most people who work in a print shop will wear old clothing and aprons.
Zinc plates release white bubbles of hydrogen gas in nitric acid which indicates the strength of the acid. Intense bubbling of fresh strong acid will create deep lines. These will be somewhat jagged and rough but this is a perfect way to create many abstract effects.
A formula called Dutch Mordant is used for etching copper in order to achieve very fine lines and aquatints.
The usual recipe for Dutch Mordant is:
10 percent hydrochloric acid
2 percent potassium chlorate
88 percent water.
Dissolve the potassium chlorate in water first. Then add the hydrochloric acid.
Because of the need for these caustic materials, it is difficult for artist printmakers to manage etching plates in their own studios. Many contemporary artists will form printmaking cooperatives or use commercial ateliers for the actual etching of plates. It is also not uncommon for artists to create and etch their plates in a commercial atelier and have it printed for them.
When I was primarily making intaglio prints I created my plates in an atelier but printed them on my own etching press. In that way I avoided the danger and mess of directly mixing the acid, but I was in control of placing my plates into the acid bath. It is exciting to see what happens when a copper or zinc plate with your design is placed in the acid. Most commercial studious have proper ventilation and it is very important that this be the case when dealing with acid.
Working on an intaglio plate requires a reasonable amount of planning, but errors occur and it often is the case that a particular effect will not work as intended. It is possible to correct and change the image by the use of a three sided scraper that needs to be kept very sharp. Frequent sharpening of the scraper is done using a sharpening stone. The scraper is used to scrape away lines or tones that are not wanted. After the metal is scraped away a burnisher is used to shine the scraped area so it will not hold the ink. A scraper us also used to create tonal areas on a plate by roughening the surface of the plate.
THE NEXT STEP, Inking and Printing the Plate
Intaglios are printed on damp, fine 100 percent rag paper. The weight and size of the paper is important and many companies specialize in producing this kind of fine art paper. The fibers need to be soft and pliant enough to be pressed into the lines and indentations of the plate. The paper has to be very sturdy to withstand the pressure of being stretched and pushed into the shape of the plate.
Paper can be soaked in a tray of water for a few minutes and then placed between blotters and rolled with a rolling pin to press out the excess moisture. This works if only a few prints are going to be made but if a larger number is needed, paper is often prepared by moistening sheets of paper with a sponge and then wrapping the package of paper in a plastic sheet overnight so the moisture will be distributed evenly.
Etching Ink consists of powdered pigment and linseed oil. It can be mixed up to order or purchased ready to use. Ink comes in different viscosities that will determine the stickiness and density of the ink. It is usually prepared and applied to the plate with a leather dauber or a felt dauber made out of used, rolled up etching blankets. A number of daubers is usually needed because a different one is used for each color of ink.
There are a number of systems of inking a plate, but for the most part, the object is to completely cover the plate with ink, including pushing it into the incised lines. After the plate is inked, the ink is wiped off with a special soft cloth, or newspaper. Some printers use their hands for a final soft wiping. This inking and wiping has to be done for each individual print.
When the plate is wiped to the artist's satisfaction, the edges are carefully cleaned off and the plate is placed on the bed of a printing press. The printer, who needs to have clean hands for this step, removes a sheet of damp paper and carefully centers it and places it on top of the plate.
Next, the paper and plate have to be covered with three wool felt printing blankets. The blanket directly on top of the paper is thin and serves to protect the print. The second blanket is very thick and soft and the last blanket is a tightly woven wool felt.
An etching press can be manually operated or have an electric motor to push the press bed, plate, paper and blankets between two rollers that exert extreme pressure on the package as it is rolled from one side of the press to the other. A motorized press is a great help if a large print is being produced. There are many manufacturers of presses and they can be both expensive and inexpensive to buy.
After the print has gone through the press, the blankets are picked up and the print is carefully removed from the press. It then has to be dried between blotters for several days. The print must dry completely. It is important to have a weight placed on drying prints so that they won't buckle.
Each time the plate is printed it needs to be inked and wiped as previously described. Each time the plate is printed the resulting print is part of an edition and is slightly less sharp than the one before. After a number of prints have been pulled, usually under 100, a plate is usually retired.
I have etched a large number of plates, but found myself inking each one differently. I have never pulled an edition because I discovered that I was actually interested in using the plate to create one of a kind prints. Most artists who want to poduce an edition of a particular image will have the plate printed by a professional printer in an atelier. Artist printmakers like myself often print unique monoprints instead of editions.
At this time in my life I no longer am making prints. I sold my printing press and all of the equipment needed for this kind of work. Years of exposure to the solvents and chemicals involved in this art have made me very sensitive to the materials used. Now I spend most of my time painting and drawing, but sometimes I miss the adventure of creating an original print. I use watercolor, acrylic or pen and ink to make art and I stay away from art materials that are injurious to my health.

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