What is intaglio?
Intaglio (say "in-TAL-yo") means "cut in". In intaglio the printing lines are below the surface of the plate. This is the opposite of woodblock printing, where the printing parts are raised. Copperplate printmaking is the most common kind of intaglio. Zinc and steel plates are also used.
Ways to make the grooves
- Engraving: the artist pushes a sharp steel tool called a burin into the copper and cuts clean lines.
- Drypoint: a sharp needle scratches the plate directly, no acid. It leaves a rough edge (burr) that gives soft, velvety lines.
- Etching: the plate gets a waxy ground. The artist draws through the ground with a needle. Acid then bites the bare metal lines.
- Aquatint: fine resin dust is melted on the plate. Acid bites tiny dots around the dust. These dots make flat areas of grey tone.
Biting with acid
In etching, the plate sits in an acid bath. The acid eats the metal only where the wax is gone. Time controls depth. A few minutes make shallow grooves and light lines. A long bite makes deep grooves and dark lines. Artists often take the plate out, cover the light lines with varnish (stopping out), and put the plate back to bite the dark lines more. Acid is dangerous, so it is used in a ventilated room with gloves and goggles.
Inking and wiping
The artist warms the plate and rubs thick ink into all the grooves. Then the flat surface is wiped, first with a stiff cloth called tarlatan and then with the palm or soft paper. Wiping leaves ink in the grooves only. Some artists leave a thin film of ink on the surface on purpose for a toned look (retroussage and plate tone). If the surface is not wiped enough, the print gets a dirty background.
Printing with a press
Damp, soft paper is laid on the inked plate. Felt blankets go on top. The sandwich is rolled between two heavy rollers of an etching press. High pressure pushes the paper into the grooves. The paper pulls out the ink and carries the lines. The edges of the plate also press into the paper, leaving a plate mark. The print is mirrored, and the plate can be inked again for many prints. Soft plates (drypoint) wear out after a few prints, while hard plates give hundreds.
Key formulas and definitions
- Intaglio = ink in the grooves, not on the surface
- Etching = wax ground + needle + acid bath
- Acid time up = groove deeper = line darker
- Engraving = burin cuts the line; drypoint = needle scratches, makes burr
- Aquatint = resin dust + acid = grey tone
- Print = mirror image + plate mark
Worked examples
1. Why does a long bite give a darker line?
The groove gets deeper, so it holds more ink. More ink on the paper makes a darker line.
2. A plate is printed without wiping the surface. What does the print show?
A dark, dirty background around the lines, because ink is also on the flat surface.
3. An artist needs both pale and dark lines on one plate. How can the artist do it?
Bite the plate for a short time, cover the pale lines with varnish (stopping out), then bite again so only the other lines get deeper.
Common mistakes
- Thinking the ink sits on top, like in woodblock printing. In intaglio it sits in the grooves.
- Wiping the grooves empty by pressing too hard with the cloth.
- Using dry, stiff paper. It will not reach into fine grooves.
- Leaving the plate in acid for too long, which makes lines merge and blur.