Light Curing Polyester, Vinylester, and Urethane Resins
Light curing of polyester, vinylester, and urethane resins is not a new technology, but the rapid and controlled curing of these resins is new. Twenty five years ago, a light cure initiator for rapid curing of polyester and vinylester resins was developed at laboratories in Germany. Sunrez has continually modified and improved this light curing technology, expanding it into new areas and extending it from thin coatings to very thick glass-reinforced laminates. Total cure times of 3 minutes are typical for parts of 3/16” and under 10 minutes for parts 3/4” thick, using open molds and hand lay-up, or machine application of the resin and glass. Additionally, new fabrication technologies and application areas are possible for both polyester and vinylester laminates. Light curing of resins is independent of temperature, therefore the cure time of parts is constant, whether cured in either hot or cold weather. Another plus is that styrene emissions can be reduced by up to 95% depending on the fabrication method used. (This is based on fabrication processes patented by Sunrez). The reduction in styrene emissions results from the cure mechanism which occurs from the top surface down.
Laboratory tests have shown that up to a 10% increase in physical properties has been seen using Sunrez light curing technology
versus MEKP cure of the same resin systems. This difference results from the more complete cure of the resin system with the Sunrez photo-initiator systems.