As space and weight constraints drive more compact, sleeker forward lighting components, automotive suppliers seek materials that can meet the challenges posed by these new designs, including higher temperatures from proximity to bulbs and thinner-wall parts for reduced mass.
Addressing this demand, GE Plastics' new Lexan Xtreme Heat (XHT) resin portfolio, one of the company's Signature Surfaces solutions, now offers automotive lighting designers new material choices for their most demanding applications.
Lexan XHT resins deliver resistance to deformation and colour shift under high-heat conditions, and surpass many competitive materials such as thermosets in recyclability potential, density, and flow characteristics. Further, when used for bezels and reflectors, new Lexan XHT resins enable direct metallisation, which eliminates the costs and environmental impact from pre-coating the part with paint or lacquer.
The ability of GE's Lexan XHT resins to withstand high temperatures is critical for today's lighting designs, which are trending toward reduced space between the bulb and the lens, higher vehicle voltages, and minimal incursion into the engine compartment. When vacuum-metallised, Lexan XHT resins can withstand temperatures of up to 200 deg C without blistering, hazing, delaminating, or losing their brilliant luster. Current resin grades are excellent candidates for auto headlamp bezels and reflectors, while others in development will target lenses and other components.
To help designers create thinner-walled lighting components that can reduce size and weight, Lexan XHT resin grades offer improved flow characteristics for injection moulding. Enhanced flow helps decrease melt temperatures and cooling requirements, decreasing cycle times by as much as 10 per cent. In new designs, the GE resins offer an opportunity to decrease wall thickness and material costs.
Compared with competitive materials, GE's Lexan XHT resins have a lower specific gravity that can help auto suppliers reduce part weight for better fuel efficiency. The GE materials have a specific gravity of 1.22 vs. 1.9 or higher for many thermoset resins. Even competitive thermoplastic materials used in lighting applications, such as polyethersulfone (PES), are as much as 12 percent denser than Lexan XHT resins.
For more information, visit www.geplastics.com"