Abstract
Triarylsulfonium compounds with relatively higher reduction potentials by introduction of electron withdrawing groups and expansion of π-electron resonance were newly designed and synthesized. These sulfonium compounds exhibited high acid generation efficiency, which were cationic polymerization ability, by electron transfer induced photo-sensitization with dyes. The thermal stability of these compounds was investigated from a practical standpoint, and also the influence of the stability by varying the counter anion was examined. Further, these sulfonium compounds were applied to radical promoted cationic polymerization and infrared-dye induced photo-sensitization.