Better Performance than Glass at a Fraction of the Thickness (0.5 mm)


Heavy, breakable and rigid glass is being replaced more and more in photovoltaic structures by films made from Specialty Polymers. These films offer the expected light transmission, weatherability, UV resistance, and mechanical performances of glass but add flexibility, weight reduction, chemical and fire resistance and self-cleanability.

Tough Enough for Long-Term Outdoor Exposure

Halar® ECTFE film has a smoother surface and lower density and thickness compared to glass.



Halar ® ECTFE exhibits extreme long-term outdoor stability when exposed to sunlight and atmospheric events. This, combined with very high transparency (over 91% total transmittance) makes it ideal for use in front-sheet and back-sheet Photovoltaic applications.

Halar® ECTFE film main features include:

  • Strong, tough and abrasion resistant

  • Broad service temperature range (from -80°C to 150°C)

  • Excellent outdoor stability (hydrolysis and UV aging)

  • Outstanding fire resistance properties (LOI > 52 %)

  • Highly transparent and smooth (over 91 % total transmittance)

  • Very good dielectric properties (=2.5 at 23°C, 1MHz)

  • Lightweight (0.084Kg/m2 for a 50μ film)

Protecting PV Cells on Solar Impulse

Solar Impulse is the first ever zero-emission aircraft powered exclusively by solar energy to fly around the globe. Solvay has dedicated its expertise and innovation capacities to this project to enable the storage and optimal consumption of energy and lightweight the solar plane.  The photovoltaic cells used are protected from harsh conditions during the flight by a transparent surface treated film, based on Halar® ECTFE. The film’s thickness was reduced to 17-20 microns, or less than 0.02 millimetres.