Ultraviolet (UV) curing is a photochemical process in which high intensity UV is used to instantly cure inks, coatings or adhesives in a wide range of industries. In the process, the first step is the absorption of UV light of specific wavelengths by the photoinitiators in the coating, this generates highly reactive free radicals which go on to start the crosslinking process of the resins and monomers. Thus creating a highly cross-linked network within the coating and converting the liquid film to a dry, solid film in-situ on the surface of the substrate. Offering many advantages over traditional drying methods, UV curing has been shown to increase production speed, reduce reject rates, improve scratch and solvent resistance, and facilitate superior bonding.
UV curing is a multi-billion dollar worldwide industry and has grown more than 10% per year, displacing conventional water and solvent-based thermal drying processes due to its increased productivity, improvement of product quality and performance, and environmentally friendly characteristics. In UV curing, there is no solvent to evaporate, no environmental pollutants, no loss of coating thickness, and no loss of volume. This results in higher productivity in less time, with a reduction in waste, energy use and pollutant emissions.
UV curing is already widely used in coating many plastic components; delivering benefits of reduced floor space, lower energy consumption, improved coating quality and lower reject rates. The challenge is to deliver coated products that can meet ever higher performance specifications including exterior automotive applications and more complicated 3-dimensional parts.