Oxidative photobleaching of phthalocyanines in solution

Metallophthalocyanines form a very important class of commercial dyes and have achieved significant success in a variety of applications, in which their photostability is of fundamental importance. On this ground, considerable data on phthalocyanine photobleaching were published over recent years. We do not intend to give exhaustive compilation of the photobleaching quantum yields, which are known for wide circle of phthalocyanines in different solvents. This review begins by discussing pertinent background information about processes following phthalocyanine excitation. Then using selected examples of the recent literature, including authors' works, we survey a variety of photobleaching effects from the fundamental origins to specific for phthalocyanine chromophore. Finally, the mechanisms of phthalocyanine oxidative photobleaching are discussed.