April 30, 2015
Researchers:Kevin Pomerleau/ Daniel Chiaccio
Room Temperature: 65 degrees F
Materials: Macdermid Plus 8,000 Universal Resistant Emulsion, 17x 15″ screen, Speedball Screen printing ink with extender, Exposure unit, Opaque Black Trash Bag, 2.5 lb paper weights
Abstract: To see if the thickness of emulsion when applied to a screen affects the amount of detail obtained in the final print.
Procedure: Using a 14″ scoop coater, We coated a thick layer of emulsion to both sides of a 17 x 15″ white 195 mesh count screen by applying less pressure to the screen allowing for more emulsion to release from the scoop coater and move onto the screen. After letting the emulsion dry for 45 minutes under ventilation, we exposed a pre made transparency using both halftone and text (the same transparency from test no. 1) by placing the transparency, emulsion side up, onto the exposure unit with the emulsion filled screen faced down over it. We then covered the entire unit with the opaque black trash bag and the 2 paper weights and set the exposure time for 5 minutes. Once the exposure was finished, we removed the weights and trash bag, and walked the screen to the washout booth (in a non light safe room) and washed the screen out.
Conclusions: The thicker layer of emulsion did not seem to make any drastic changes to the final print, there is still a lack of mid tones, however there is less blow out in the screen (a portion of the image which is supposed to have tonal range, but prints a solid flat plain of color instead) particulary in the areas of the koalas fur. From this point we wanted to see if increasing the length of exposure time for the Macdermid Emulsion would produce a larger variation in mid tones on our screen, while giving us a final solidified dark blue emulsion color.