It has been shown that photoinitiators and their decomposition fragments remaining in a UVcured coating can be easily extracted by standard solvents, suggesting that the possibility of contact with food substances is high. Products with a molecular weight below 250 g/mol have been shown to be easily extracted from cured coatings. One strategy to reduce migration is to employ larger molecules that will become trapped in the cured polymer and, thus, cannot be extracted.1 European regulation EC 2023/2006 discusses the potential migration of small molecules (like photoinitiators and by-products) from cured inks through layers of packaging into food with the aim to provide a quantitative directive for producers of UV-curable inks and coatings. The specific directive 2002/72/EC relates to plastic materials intended to come into contact with food.
Goals of polymeric photoinitiators
Industry: Photochemistry / Photoinitiators