Recent advances on naphthalic anhydrides and 1,8-naphthalimide-based photoinitiators of polymerization

The design of photoinitiators of polymerization is an active research field and the development of initiators activable in the visible range and under low light intensity have been the focus of numerous research efforts from both the academic and industrial communities. Recently, two families of polyaromatic compounds, i.e. 1,8-naphthalic anhydride and naphthalimides, have been extensively studied by different research groups due to their easiness of synthesis and the possibility to easily tune the photophysical properties. Especially, panchromatic, crosslinkable or water-soluble photoinitiators could be easily developed starting from the benchmark and cheap 1,8-naphthalic anhydride. In this review, an overview of the different photoinitiators based on naphthalic anhydride or the naphthalimide scaffold is presented. Based on the diversity of structures reported in the literature, a structure-performance relationship could be established in this review.