US Patent 11851511 Polymerization photoinhibitor

Provided herein is technology relating to polymerization and producing polymers and particularly, but not exclusively, to methods, systems, and compositions for producing articles using three-dimensional printing and for improving control of polymerization using a polymerization photoinhibitor having fast back reaction kinetics such as hexaarylbiimidazole compounds and bridged hexaarylbiimidazole compounds.