Hybrid nanocomposite coating films, prepared by the incorporation of epoxidized sunflower oil into organoclay, can be cured by ultraviolet radiation with either cationic or hybrid initiation. The organoclay used in this study was prepared by a cationic exchange process in which sodium ions were replaced by alkyl ammonium ions. The effects of types of photoinitiators on energy consumption in the curing process were studied. Formulations with a hybrid photoinitiator required less energy in the curing process than those with a cationic photoinitiator. Moreover, the physical properties of dried films were examined as a function of the organoclay incorporation, and it was found that the hardness of the films increased as the amount of organoclay in the formulation increased. The X-ray diffraction patterns of an ultraviolet-curable organoclay-incorporated film showed an exfoliated structure of the organoclay in the ultraviolet-curable coating film. (C) 2008 Wiley Periodicals, Inc.