GCM 240 Lecture Notes - Lecture 10: Gum Arabic, Surface Tension, Wetting

• School: Ryerson University
• Department: Graphic Communications
• Course: GCM 240
• Professor: Nikita Kuzmin

Document Summary

Week 10 - other materials used in printing. Fountain solution is also known as dampening solution or water. Used to keep the non-image areas of the printing plate clean from ink, by desensitizing the plate to ink (non-image areas) Wetting agent or ipa (reduces surface tension) Fountain solution is made from mix concentrate or solution according to directions. Conductivity is the best measure of proper concentration. Measured in micromhos ups looking symbol, conductivity indicates how well electrical charges can be carried by the solution. As the quantity of fountain solution concentrate the fountain solution is increased, the conductivity of the solution rises proportionally. In order to determine how much has been added, we must measure the conductivity on freshly prepared fountain solution. Fountain solution can be reused, but if often changed weekly. Dampening solution often includes recirculation and cooling. A decrease in ph means an increase in h+ ions.