In the previous test I learned that completely covering the copper plate with either Lascaux 2094 Wash resist worked or Lascaux 2092 Stop-out resist to completely cover the copper plate eliminates open biting. However the Lascaux Stop-out is difficult to remove and is not compatible with our standard sodium carbonate stripper bath. I recreated the previous experiment using Z-Acryl Stop-Out Resist instead of Lascaux Stop-out product.
Date: March 3, 2010
Researcher’s Name: Maya M. Bajak
Plate Material: .032 Copper
Plate Size: 5 in x 5 in
Room Temperature: 74°
Each plate was degreased with Bon Ami and water. I painted Z-Acryl stop-out on the edges of the plate and then applied Lascaux wash resist in the center occasionally diluting it with water for more reticulation. The copper plate was air dried for 10 minutes and box dried for 20 minutes. On a second plate I painted Lascaux Wash-Resist over the entire surface making sure every portion of the plate was covered to prevent open biting. With a small brush I painted Z-Acryl Stop-out on top of the Lascaux Wash resist to see if it would still prevent the plate from etching. This plate was air dried for 15 minutes and box dried for 20 minutes.
Each plate was etched in a vertical etching tank of Ferric Chloride at 36.5° Baume.
Timed Application of Mordant
Plate 1 – 25 Minutes
Plate 2 – 20 Minutes
Removal of Grounds
The grounds were removed using a stripper bath of Arm & Hammer Washing Soda and water (100 grams/1 liter) I placed the plate in the bath for 10 minutes. The ground came off easily using a nail scrubber under running water.
After Bath Evaluation
No open-biting and a great texture on both plates. The Z-Aryl Stop-out seems to have worked well even applied over the wash ground.
The first plate was inked with a mixture of half Charbonnel Luxe Noir Black and half Daniel Smith Creamy French Black Etching ink. The second plate was inked with Graphic Chemical and Ink Co. Bone Black #514. Both inks were carded onto the copper plate with mat board scraps and wiped with used tarlatan.
Paper Type: Hahnemuhle Copperplate
Paper Soaking Time: 20 Minutes
Press Blanket Setup: Small Takach, 2 Blankets, 8.5 Pressure
Both plates printed successfully. I applied the Z-Acryl Stop-out over the wash ground and it did an excellent job preventing areas of the plate from being etched.