Photoinitiator, novel compound, and photocurable composition

摘要

A photoinitiator is provided which exhibits excellent photosensitivity, yields colorless products, and is usable in thick layer UV curable coating. A novel chemical compound is also provided which is usable for the photoinitator. Photocurable composition is also provided which has these properties. The photoinitiator consists essentially of a compound having a molecular weight of 1000 or less, and having a chemical structure represented by the following formula (1), wherein R₃ and R₄ independently denote a specific alkyl group, and R₁ and R₂ independently denote an electron attracting group or a specific alkyl group, and weight percentage of a chemical structure element represented by the following formula (2), which is expressed in formula (1) based on the total molecular weight of the compound, is 17% to 54% by mass.