Used primarily as a photoinitiator in UV-curable systems such as inks, coatings, and adhesives. It absorbs ultraviolet and visible light, generating free radicals that initiate polymerization of acrylates and other monomers. Commonly found in dental composites and printing formulations due to its efficiency and compatibility with other photoinitiators like benzophenone. Also employed in some photochemical research applications for controlled radical reactions.