Evaporation Equilibrium of Mixed Volatile Solvent Ink Systems.

Flexographic and rotogravure printing inks often contain more than one solvent. The solvents evaporate from ink fountains at different rates causing solvent imbalance and consequent printability, drying rate, and color strength problems. Continuous, uniform performance can be achieved only if lost solvent is replaced in the same proportion as initially evaporated. This paper deals with the theory of evaporation equilibrium, laboratory test methods to determine composition of evaporated solvent, and data relevant to numerous ink systems.