Two-photon absorption property and photopolymerization sensitizing efficiency of asymmetrical benzylidene cyclopentanone dyes

Five, asymmetrical benzylidene cyclopentanone dyes were synthesized and their one- and two-photon photophysical properties were investigated. Measurements revealed that the two-photon absorption cross-sections (TPACS) of these compounds in chloroform were of the order of 10−48 cm4 s molecule−1 photon−1 in the wavelength range 700–880 nm. The sensitizing efficiencies of the dyes in photopolymerization systems were also considerable and matching those of the commercial initiator o-Cl-hexaarylbisimidazoles (HABI). The two-photon polymerization results proved that these photosensitizers possess large potential for two-photon absorption induced polymerization.