Photoinitiator is a key component of light-cured products, and it plays a decisive role in the light-curing rate of light-cured products. Due to the different absorption of radiation energy, it can be divided into ultraviolet light initiator (absorbing ultraviolet light region 250-420nm) and visible light initiator (absorbing visible light region 400-700nm). At present, the photoinitiator used in photocuring technology is mainly ultraviolet photoinitiator.