2.2'-Bis(2-chlorophenyl)-4.4'.5.5'-tetraphenyl-2'H-1.2'-biimidazole

2.2'-Bis(2-chlorophenyl)-4.4'.5.5'-tetraphenyl-2'H-1.2'-biimidazole 5g : 2.2'-Bis(2-chlorophenyl)-4.4'.5.5'-tetraphenyl-2'H-1.2'-biimidazole is a high-efficiency photoinitiator for UV-curable coatings and resins.