Pollution-preventing anionic lithographic inks

Lithographic printing presses use aliphatic and aromatic solvents for cleaning various surfaces, which are coated with the ink. The conventional printing inks also contain volatile solvents. During printing and cleaning operations, volatile organic compounds (VOCs) present in the inks and cleaning solvents are lost to the atmosphere by evaporation and these losses are quantifiable and alarmingly high. A new type of ink based on castor oil, which completely eliminates emissions of VOCs, has been developed. Synthesis of resins and the kinetics of washing of the ink, similar to the recently announced pollution-preventing ink [development of a VOC-free lithographic printing system. TAGA Proc., 324], with water at a slightly elevated pH are studied. A correlation between the mass-transfer coefficient characterizing the washing of ink and the experimental process variables is confirmed. New data are also reported on flake-formation dynamics. (C) 2003 Elsevier B.V. All rights reserved.