Microemulsion printing ink

摘要

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.