Photopolymerization Reactions For Imaging Applications : Role Of Multicomponent Photoinitiating Systems

The role of multicomponent photoinitiating systems - based on various combinations of a bis imidazole derivative, an aminobenzophenone, an iodonium salt and an amine - in the photopolymerization of an acrylate formulation under light irradiation at 365 nm, has been investigated. Two photoinitiation processes occur a direct process where the light is absorbed by the bis imidazole derivative and a sensitized process where the ketone plays the role of the absorbing species. The different involved reactions are defined and the role of each partner is explained.