Low-VOC, low-viscosity UV cationic radiation-cured ink-jet ink system and visible light-curable system

Ink-jet inks are very low in viscosity. The low viscosity is important not only for transport of the ink through the nozzle, but also for drop formation and integrity. The objective of this project was to develop zero VOC, low viscosity systems for ink-jet inks so that in the future, printers with UV cationically curable ink-jet ink cartridges can be developed.; UV curable coatings and inks with zero VOC and less than 10 cPs viscosities were formulated with cycloaliphatic epoxides. Cure was achieved through the use of cationic photoinitiators which generate a strong acid when exposed to UV light. The strong acid initiates the cationic curing of epoxides.; A zero VOC, visible light curable coating can be formulated with cycloaliphatic epoxy resin from Union Carbide and aromatic liquid epoxy Epon 828 from Shell Chemical Company. Cure is achieved through the use of a cationic photoinitiator which, when exposed to visible sunlight generates a strong acid which initiates the curing of epoxy functionalities cationically. However, no cure yet is possible with fluorescent light.