The Process and benefits of Nitrogen Inertingfor UV curable Coatings with and without the presence of Photoinitiator

Free radical chemistry is still the most widely used UV curable system. There are a wide range of raw materials and applications available to the formulator and end user to achieve the desired properties for their film. During UV curing in air, the presence of oxygen can have a detrimental effect on the cure response of free radical systems - especially for thin-film coatings. Oxygen reacts with the free radical and forms peroxy radicals by reaction with the photoinitiator, monomer or propagating chain radical. The reactivity of the peroxy radicals is insufficient to continue the free radical polymerisation process, leading to chain termination and resulting in an under cure system.