POLYMERIZATION PHOTOINITIATORS - EXCITED-STATE PROCESSES AND KINETIC ASPECTS

Nowadays, radiation curing is a well-established technology that has developed and grown rapidly on an industrial scale. The most prominent applications initially related to the UV curing of coatings, while reprography (printing plates, integrated circuits, photoresists, solder masks) represents a second class of applications. More recently, laser-induced curing - holographic recording, 3D pattern formation under laser exposure and holographic optical elements - have developed as new, promising and exotic techniques for the near future. The practical development of these technologies obviously requires new light devices and, above all, new photosensitive materials. This article is mainly concerned with an overview of the different possibilities for the photoinitiation step of light-induced polymerization reactions and includes a general discussion on key concepts relating to excited-state reactivity and the structure of photoinitiators. © 1990.