Initial photoyellowing of photocrosslinked coatings

Abstract

Initial photoyellowing occurs immediately afer exposure to the curing radiation in UV and EB coating systems. Since it is in part reversible, it is a major concern for the exact colour matching in quality control. Here, the influence of a variety of photoinitiators, resin systems as well as additives and stabilisers are compared with respect to their photoyellowing performance.