The Polymergravure Process
We use the environmentally friendlier photopolymer plates which, unlike the traditional copperplate photogravure process that uses acids, washout in plain water, are much easier to work with, and are quicker to process.
Outputting film.
The image file is printed onto a sheet of film with an inkjet printer.
The plate is twice exposed to ultraviolet light — once in contact with an aquatint screen (a stochastic, or random patterned screen producing a similar effect to a halftone) and then to the image positive.
Plate washout in water.
The plate is exposed and then immersed in water and gently brushed for several minutes. The washout removes the unexposed and unhardened areas of polymer that become the shadows, while those that were exposed to ultraviolet light harden, become insoluble, and remain on the plate forming the highlights.
After processing the plate is dried and re-exposed to ultraviolet light to cure it and enable it to withstand the pressure of the press.
Pulling the print.
The plate is inked and gently wiped by hand using tarlatan, a material similar to cheesecloth, to remove the ink from the lightest areas, but being careful to leave ink in the grooves of the darkest shadow areas.
The finished plate is then placed on the bed of an intaglio press, covered with damp etching paper and the felts and run through the press. Under pressure the ink is squeezed out of the deep grooves and onto the paper to form the image. Carefully, the felts are lifted and the print pulled away from the plate and laid out to dry. The plate can then re-inked, wiped and printed until the edition is complete.