Abstract: A printing ink useful for "waterless" printing processes comprising a water-in-oil microemulsion wherein the water phase is present in an amount of about 5 to 20 wt. %, based on the weight of the ink. The water phase contains about 0.5 to 3 wt. %, based on the weight of the ink, of a surfactant which will not lower the surface tension (as measured at ambient temperature) of the ink, but will preferably increase the surface tension of the ink by at least about 5%. The ink optionally contains about 0.05 to 0.5 wt. %, based on the weight of the ink, of a water-soluble polymer capable of producing a viscosity in the water phase of about 5 to 10 poise as measured at ambient temperature.

Abstract: A printing ink composition having a high degree of rub-off resistance comprising (a) a dispersion of a pigment in a vehicle containing a C.sub.7 -C.sub.40 oil and (b) a polymer latex emulsified in said dispersion. When employed for printing at high speeds, an anti-misting compound such as tridecyl acid phosphate, phosphoric acid, glycerol, or propylene carbonate is preferentially added to the ink composition. Where cost is not of paramount concern, a polytetrafluoroethylene wax is preferentially added to the ink composition.

Abstract: Water-based ink compositions comprising water, a pigment, a nonionic surfactant having a solubility in water of less than about 0.5 wt. % and a solubilizing agent sufficient to solubilize substantially all of the nonionic surfactant.