Sabic (Riyadh / Saudi Arabia; www.sabic.com) has introduced new grades of its “Lexan” PC resins for LED automotive lighting. The chemicals and plastics giant noted that the complexity of LED headlights continues to increase with current high-end products containing up to 200 components and weighing nearly 6 kg because of their additional functionality. In addition, car manufacturers are striving to create highly distinctive lighting parts to differentiate and increase the appeal of their vehicles.

As a consequence, Sabic has launched Lexan HF4010SR to help those automotive customers seeking to produce complex headlamp bezels with enhanced styling, but at a lighter weight and lower overall system cost.

The resin has been engineered with an even lower draft angle that is typically recommended for PC tools – between 0.5-1 degree less than the usual 3-5 degrees. A low draft angle enables greater styling freedom as well as a larger optical surface but, the lower the angle, the more problems converters face with parts sticking in the mould, creating scuff marks and sometimes cosmetics effects.

Sabic said that according to market feedback, the resin offers enhanced styling possibilities, the ability to integrate more features and functionality into each component as well as the prospect of having fewer bezels, leading to weight and cost reductions. Bezels that are injection-moulded in Lexan HF4010SR can be directly metallised (no need for priming). In addition, gloss and reflectivity performance under high temperatures are said to be very good.

Three new grades have also been added to Sabic’s Lexan XHT line in order to combat the problems with flow that can still occur from the considerable heat generated in LED headlamps. Lexan XHT1171, XHT2171 and XHT3171, which can be used as a drop-in alternative to standard PC, are said to offer improved flow at high temperatures compared to other high-heat PC materials.

In a recent study carried out by Sabic, results showed that a bezel moulded in Lexan XHT2171 could weigh 37% less than a bezel made from a rival PBT material, thanks to possible reductions in wall thickness and lower density. According to the Saudi group, Lexan XHT2171 has the potential to enable cost savings of up to 40% per bezel.