Photolatent bases: new catalysts for UV-curing of coatings

A new approach for the cure-on-demand of coatings involves the photo-generation of a base catalyst, which then causes resins to crosslink and cure via a base-catalysed mechanism. The advantage of using a photolatent base catalyst is to be able to cure a wide range of conventional coatings at low temperatures. The influence of different parameters on the photolysis of two latent catalysts in a number of resin systems was investigated by infrared (IR) spectroscopy. The mechanical properties of the cured coatings were characterized by hardness measurements and then correlated to the degree of conversion and the photoefficiency of the photolatent base catalysts.