A viscous to semisolid suspension of finely divided pigment in a drying oil such as heat-bodied linseed oil. Alkyd, phenol-formaldehyde, or other synthetic resins are frequently used as binders; and cobalt, manganese, and lead soaps are added to catalyze the oxidative drying reaction. Some types of inks dry by evaporation of a volatile solvent rather than by oxidation and polymerization of a drying oil or resin. Use distribution is: offset 40%, gravure 23%, flexographic 18%, letterpress 9%, screen 4%, other 6%. For further information refer to National Printing Ink Institute, Lehigh University, Bethlehem, PA.