Part II - Making the Plate

The prepared image is printed on a blank polymer plate. These plates are available from a number of sources and are also used in the commercial printing world. There are a number of types though the pandemic has made some varieties very scarce. I print my plates on an Epson 3880, using the manual front loading process with the plate nested in a matte board carrier.

The plate, now bearing the image printed on its surface, is placed in a UV box and exposed for 90 seconds. These exposure times vary according to the type of UV box, the type of polymer plate and other factors. My box was manufactured by Edwards Engineered Products. http://www.eepjon.com/uv.htm. I bought it several years ago for making paladium and other alternative process prints. It does an excellent job with these polymer plates as well. 90 seconds is the optimum exposure time for my workflow with my box.

In essence, the ultraviolet light penetrates into the polymer, causing it to harden. In lighter area of the image where there is little or no ink printed on the plate, more light passes and the polymer becomes relatively hard. Conversely, in the darker areas of the image where there is more ink, less light penetrates onto the polymer which remains relatively soft. This is the basic relationship that makes the whole process work.

After exposure, the plate is placed in a water bath (about 68 degrees F) and gently washed with a soft sponge. This removes the ink and excess polymer that was not hardened by the UV light. The softer areas (where more ink was printed on the plate) become indented and grooved, which will hallow them to hold more ink in the next step (see Part III) than the harder areas. and thus print darker on the water color paper in the final print.

After the water bath, the plate is then dried, heated and returned to the UV box for another 10 minutes of exposure to fully harden the polymer. At the end of this process the images can be seen on the face of the plate when held in a cross light.

The edges of the plate are now trimmed in a heavy cutter, then sanded and filed to remove burrs and sharp edges that might damage the paper when it is put through the press.

The plate is now ready to be inked and printed. (See Part III of this blog.)