Polycarbonates for LED lights in extreme environments

International Day of Light on May 16, 2021


Challenging applications in swimming pools and explosion-proof lights

LED light sources have proven to be energy-saving and long-lasting which makes them economical light sources and are widely used in buildings, vehicles and street lighting. Light guides, reflectors, diffusers and lenses must be designed to ensure optimum use of LED light.

Covestro has spent years developing a customized portfolio of transparent, translucent, reflective, as well as thermally conductive and flame-retardant grades of polycarbonate plastic to meet these needs. In that way, the company is supporting more sustainable lighting technologies, to which the International Day of Light on May 16, 2021, is dedicated.

LED lighting in swimming pools

Operating LED lamps under water puts special demands on the materials involved. In cooperation with Brazilian swimming pool equipment supplier Ecopyre Lighting, Covestro developed an integrated solution using the thermally conductive polycarbonate Makrolon® TC. It features high dimensional stability during manufacture and operation of the lights, thereby preventing water ingress (ingress protection or IP).

The letters "TC" in the type designation stand for "thermally conductive" and indicate that the plastic also has good thermal conductivity. This makes it ideal – like the other types in the TC portfolio – for efficient thermal management in which the heat generated by the LEDs is well dissipated. In addition, the plastic complies with the chemical resistance required for use in swimming pool water.

Lenses for explosion-proof LED lamps

The highly transparent product Makrolon® is even suitable for lenses in explosion-proof lamps, as demonstrated by a recent case study with safety technology supplier R. Stahl. The lights comply with Categories 2 and 3 (for Zones 1 and 21, or 2 and 22) of the EU ATEX directives1 for industrial environments where highly explosive dust and gas atmospheres may occur during normal operation. These include oil platforms, refineries, and also certain chemical plants.

R. Stahl AG, a German trendsetter for safety technology in potentially explosive atmospheres, was looking for an optical material solution for LED safety lighting that could be used worldwide. The decision was made in favor of the transparent plastic Makrolon®, which enables light-focusing optics and is applicable at elevated temperatures of 60 to 85 degrees Celsius.

Polycarbonate is a thermoplastic that allows efficient development and production of optical parts for LED-powered lights. The various Makrolon® types can be used for injection molding and extrusion. Stronger and lighter than glass, polycarbonate also facilitates savings in energy and CO2 emissions.

1 EUR-Lex - 32014L0034 - EN - EUR-Lex (europa.eu)


About Covestro:

With 2020 sales of EUR 10.7 billion, Covestro is among the world’s leading polymer companies. Business activities are focused on the manufacture of high-tech polymer materials and the development of innovative, sustainable solutions for products used in many areas of daily life. In doing so, Covestro is fully committed to the circular economy. The main industries served are the automotive and transportation industries, construction, furniture and wood processing, as well as electrical, electronics, and household appliances industries. Other sectors include sports and leisure, cosmetics, health and the chemical industry itself. At the end of 2020, Covestro has 33 production sites worldwide and employs approximately 16,500 people (calculated as full-time equivalents).

Forward-looking statements

This news release may contain forward-looking statements based on current assumptions and forecasts made by Covestro AG. Various known and unknown risks, uncertainties and other factors could lead to material differences between the actual future results, financial situation, development or performance of the company and the estimates given here. These factors include those discussed in Covestro’s public reports which are available at www.covestro.com. The company assumes no liability whatsoever to update these forward-looking statements or to conform them to future events or developments.