UV-curing of conformal coatings is the most modern solution when transforming conformal coating from liquid to a solid state. These materials offer an increased flexibility for the process management. UV-curing conformal coatings are more environmentally friendly than a classical varnish because they do not require any solvent and hence represent VOC free materials.

Traditional conformal coatings are resins diluted into solvents.
Successful examples of this class of materials are Bectron? PL 1104 (acrylate resin based) and Bectron? PL 4122-40E BLF FLZ (alkyd-polyurethane resin-based).

Varnishes are coming with quite some advantages. They provide a preliminary cleaning of the surface by the solvent. Experiences in application exist since decades. However, the solvents are more and more questioned as a source of volatile organic compounds (VOC), an increase of the CO₂-footprint due to the heat which is necessary to evaporate the solvents and, hence, creating additional costs.

UV-radiation to cure a polymer is a well-established technology. In most applications UV-radiation allows full cure of the material within an instant of seconds.

UV-cure sounds attractive because it offers fast processing and a shorter cycling time, in contrast to a furnace process or a day lasting moisture cure. UV-curing materials usually do not contain organic solvents and hence can be considered as VOC-free; the term 100%-material is also used in this aspect. No solvent also means no risk of bubble formation due to solvent evaporation. No solvent also disburdens from a complicated optimization of a furnace profile. Finally, an UV-cure equipment requires less space in factory than a line furnace. If the UV-energy is well used and the design of the material is well done, one might expect a better energy efficiency of the cure and an improvement on the CO₂-footprint.