A new liquid silicone rubber (LSR) material is said to meet the demand for increasingly higher heat/brightness cutting-edge LED technologies. The optically clear LIMS (liquid injection molding system) X-34-1972-3 from Shin-Etsu Silicones of America (SESA), Akron, Oh., has a transparency of 95%, making it ideally engineered for expanding LED applications in street lighting, automotive, and exterior illumination.
Moreover, its superior high temperature resistance compared to clear thermoplastic resins allows molded silicone optics to be positioned in close proximity to the LED light source without yellowing or cracking over extended operating life spans. It has a 70 Shore A hardness, a refractive index of 1.41, tensile strength of 1087 psi and tear strength of 106,208 lbf/in. SESA’s North American marketing manager Eric Bishop notes that the new material offers an unparalleled combination of heat resistance and clarity for next-generation high-brightness LED systems which are getting hotter as light output continues to increase. Bishop also added that the material has been tested in-house and at customers with promising results.