Master Bond Polymer System UV15-42C is a new one component, high viscosity, optically clear, tough UV curable polymer system with extended capability of -80°F to +300°F. It is fully reactive, does not contain any solvents or other volatiles and does not embrittle even upon exposure to low service temperatures. When exposed to a source of UV light of appropriate wave lengths and adequate intensity, it cures quickly to product tough and durable non-yellowing and chemically resistant adhesives, sealants and coatings with excellent electrical insulation properties. The cured UV material features low shrinkage, unmatched dimensional stability and excellent adhesion to various substrates. UV15-42C is a hard, durable system capable of curing sections up to 250 thousandths of an inch. Unlike many other UV curable products, the high viscosity Master Bond UV15-42C polymer system is not inhibited by air and exhibits a desirable fast curing rate at ambient temperatures even in thicker sections. Cure time depends on the type of UV lamp, the wave lengths and the amounts of the UV15-42C, the thickness of the section to be cured, etc. Cure times can be as little as a few seconds depending upon the factor mentioned above. Commercially marketed 200 watt/inch medium pressure mercury vapor or equivalent UV light sources are recommended. Maximum UV absorption takes place in the 280-365 nanometer range. No solvents or other vapors are released during the curing process which takes place with minimal shrinkage from the liquid to the solid state. The cured material exhibits a most desirable performance profile including outstanding durability, toughness, dimensional stability, non-yellowing color as well as excellent adhesion to many substrates ranging from glass and steel to polyester films and polycarbonates. The self life of the system is 6 months at room temperature in original, unopened containers. The system should be stored in a darkened area.