Photocuring by infrared irradiation using upconversion emission

Abstract

Infrared-to-visible upconversion emission was used for photocuring of a pentaerythritol tetraacrylate (PETA) by infrared laser irradiation to achieve local polymerization on an upconversion phosphor. Submillimeter-sized, cone-shaped and solid poly (PETA) was successfully formed on a Y 2O3 compact doped with 5 mol%Er under 985 nm diode laser irradiation with about 900 mW power. By changing the irradiation time, it was found that the formation of the cone starts in seconds and takes minutes to form a millimeter-sized cone. The correlation between the irradiation time and the cone volume was linear in the seconds-to-minutes time region with 800-900 mW irradiation powers. ©2006TAPJ.