SABIC Innovative Plastics’ Ammonia-Resistant Lexan DMX Resin Extends Product Life of Norka’s Energy-Efficient LED Luminaires

Norka previously made luminaires with incandescent bulbs and standard PC; however, the fixtures had to be discarded after about a year when the bulbs burned out and the plastic had become hazy from ammonia. With the goal of creating an environmentally responsible luminaire with better energy performance and extended life, the company turned to
LEDs – and needed a better plastic that could match their long lifespan.

“Norka takes pride in technology leadership and we seek out suppliers that share our commitment to the latest innovations with the best materials available,” said
Martin C. Stäcker, CEO, Norka. “That’s one reason why we have collaborated for many years with SABIC Innovative Plastics. Another reason is their ability to quickly provide specialty solutions – like new Lexan DMX resin – for a wide range of unique lighting products. We know we can always rely on SABIC Innovative Plastics to meet our exact requirements, no matter how demanding.”

“This specialized application for Lexan DMX resin showcases important strategic initiatives at SABIC Innovative Plastics,” said Rob de Jong, product market leader Europe, Lexan copolymer resins, SABIC Innovative Plastics. “We are continuing to invest in our extreme performance portfolio of Lexan copolymer resins to give customers like Norka fresh and exciting design options to differentiate their products, expand into new markets and increase overall quality and performance. We are also focusing on innovative materials that can enable the design of sustainable applications, such as energy-efficient LED lighting.”

Superior Performance vs. PMMA and Standard PC

Norka initially tried polymethyl methacrylate (PMMA) for the Luzern LED luminaire but found that this material did not provide a high enough heat deflection temperature (HDT) or sufficient impact resistance, or perform as well as desired on the Glow Wire Ignition Test (GWIT). In contrast, Lexan DMX copolymer provides a GWIT of 850C, a key requirement for lighting applications in some countries such as France to fulfill the railway norm in combination with better toughness.

Lexan DMX resin provides a pencil hardness of H, 2.5 times the surface hardness of standard PC, as well as excellent scratch resistance without requiring specialty coatings. When exposed to ammonia vapor, Lexan DMX resin retains its transparency, smooth surface finish and ductility, resulting in a luminaire that continues to look good, transmits light effectively and avoids brittleness that could pose a safety hazard.

For the Luzern luminaire, the water-clear SABIC Innovative Plastics material is extruded into a long tube to enclose the LED light strip.

Other potential applications for Lexan DMX copolymers are keypads and touch screens for electronics, bezels for televisions and notebooks, lenses, and coextruded film and sheet for scratch protection.

SABIC Innovative Plastics will be showcasing its expanding portfolio of high performance materials for the LED industry at K’ 2010. Norka’s Luzern 38 tubular luminaires with LEDs, along with other new applications will be highlighted, demonstrating
SABIC Innovative Plastics commitment to the LED industry.