Name: Mady Lacaprucia and McKenzie Stuetzel Date: 11/21/17
Room Temperature: 68 Degrees Fahrenheit Humidity, ect: Not humid
Experiment Title: Test 2 – Double-Tack Adhesive Tape with Improved Bitmap
Experiment Goal: To see how new knowledge on bitmapping for silkscreen will affect the quality of our prints, using the new method of applying emulsion to the mesh first, and then adhering using double-tack adhesive sheets.
Plate Preparation: We first printed out a new positive using different bitmap settings. We learned that when bitmapping for silkscreen, you should find the correct frequency by taking the mesh count and dividing by 5. Therefore, since we are using a silkscreen 160 mesh, the frequency we used was 32. We also learned that 22.5 is an ideal angle to use, as it is halfway between 0 and 45 and will create less of a moiré effect.
Two week prior to exposing, we had coated a screen using a single layer of emulsion. We exposed it for five minutes and then washed out the extra emulsion. The emulsion did not have the issue we had previously had where it came off in places it shouldn’t have; however there were some areas that were supposed to wash away that would not wash away completely or at all. We think that this may be due to the emulsion having been sitting on the screen for too long before being exposed.
Conclusions & Procedure:
We printed this plate using Gamblin Bone Black mixed with 00 burnt plate oil on Hahnemuhle Copper Warm White on a Takach press with a pusher and a sizing catcher.
These plates held a lot of ink and printed dark, just as in the previous test. We suspect that this may be due to only using one layer of emulsion. We think that one layer may not be thick enough to completely cover the texture of the mesh, and that is why the plate is holding so much tone in areas that should be printing white. In the next experiment, we are going to try using two coats of emulsion to see if this solves our problem.