Chapter 10 - New Applications

Abstract

Because of many advantages of ultraviolet (UV) curing, a lot of new applications for radiation-curable coatings are emerging. A recent application was an UV-curable sealer coating for fiber-reinforced plastics like sheet moulding compounds (SMC) or bulk moulding compounds (BMC). The main problem to be solved with such sealers is the porosity popping. During the moulding of the compounds, voids are formed that can entrap air or solvents. This air is afterwards released during basecoat or clearcoat baking, resulting in the formation of unwanted craters or other defects. UV-curable sealers were based on low viscosity formulations that can flow into the voids and seal the voids within seconds upon curing to prevent air release. The chapter describes current and planned UV applications in the automotive industry from the view of equipment suppliers at the RadTech Asia Conference. The current applications described are varnishes on headlamp lenses, varnishes on reflectors, and varnishes on instrument panels. The potential applications that might come pretty soon are car refinish coatings, primers or sealers on plastics and SMC components, and scratch-resistant top clear coats.