Photoinitiator classification and photoinitiator industry chain

Photoinitiator, also known as photosensitizer or photocuring agent, is a kind of compound that can absorb a certain wavelength of energy in the ultraviolet region (250-420nm) or the visible region (400-800nm), generate free radicals, cations, etc., and thus trigger the polymerization of monomers and crosslinking curing. According to different reaction principles, photoinitiators can be divided into free radical photoinitiator, cationic photoinitiators and anionic photoinitiators. At present, there are only free radical photoinitiators and cationic photoinitiators in industrial production. The free radical photoinitiator can be divided into cracking type photoinitiator (also known as type I photoinitiator) and hydrogen capture type photoinitiator (also known as type II photoinitiator) according to the different mechanism of generating free radicals.

Generally, the amount of photoinitiator used in the photocuring material is 3%-5%. However, due to the relatively high price of photoinitiator, its cost generally accounts for 10%-15% of the overall cost of photocurable products. Photoinitiators are located in the middle and upper reaches of the photocuring industry chain. The upstream raw materials are mainly sulfhydryl compounds, and the downstream are applied in photoengraving and supporting chemicals, UV coatings, UV inks and many other fields. The terminal applications span electronic products, home decoration building materials and medicine and medical treatment.

With the increment of downstream application fields and the replacement of solvent-based and water-based materials by photocuring materials, it is expected that the annual compound growth rate of China's photoinitiator market will reach 20% in the next few years and reach 15.589 billion yuan by 2028.