Polycarbonate Film:
For When Seeing Clearly Matters Most
By Ahmet Kizilirmakli

hen it comes to the effective protection of front-line workers against pathogens, the current COVID-19 pandemic has revealed a gap in the clear-view personal protective equipment (PPE) market. Conventional face shields and other transparent safety gear often fail to ensure adequate long-term anti-fog performance, especially in facilities where high humidity and temperature fluctuations can occur. Subsequently, when seeing clearly matters the most, protective eyewear and shields may not be worn as required or must be taken off for frequent wiping, thus potentially risking the safety of users. A polycarbonate film with a special one-side anti-fog coating helps personnel in healthcare and other exposed environments maintain a clear view over longer time periods even in areas subjected to high humidity and sudden temperature changes.

Dedicated research in polymer and coating technology to overcome these constraints has resulted in a film that extends the time-to-fog under these conditions. This allows the users of visors and goggles manufactured from this film to concentrate on their jobs in the safest way without being impaired by fogging.

Longer optical clarity
The anti-fog film combines the transparency, impact strength and abrasion resistance of the basic polycarbonate material with a new one-side coating technology that minimizes the specific reduction in visibility caused by fogging (figure 1).

In testing under harsh conditions, the technology has confirmed its anti-fog performance without exhibiting hazing or flashover at saturation. Several pilot applications for healthcare facilities and meat packing plants have shown to provide longer optical clarity when compared to conventional clear-view products. The effect is particularly apparent in work environments with transition zones between high and lower humidity as well as between air-conditioned and warmer areas.

This makes the anti-fog film suitable for personal safety equipment such as visors and goggles for healthcare, medical research and laboratories. Further target applications include medical instrument lenses and displays, industrial and automotive cluster lenses as well as motorcycle visors and ski goggles.

Balanced high property profile and excellent processability
Beyond long-lasting optical clarity, the anti-fog film also provides good compatibility in contact with disinfectants, detergents and common glass cleaners. The film withstands repeated cleaning on both sides; for example, a 50/50 mixture of isopropyl alcohol (IPA) and water or dilute soap and water (Dawn or any other liquid dish soap) would be the best recommendation.

Further characteristics include high tensile and tear strength, good pencil hardness on the coated side and low discoloration (yellowing).

Designers and manufacturers of clear-view safety equipment will appreciate the film’s high thermal resistance and low shrinkage for thermoformed applications. Regular manufacturing methods used in the industry such as cold bending, thermoforming and die cutting can be used to process this film, eliminating need for specialized equipment and keeping manufacturing costs low. Its printability supports customized aesthetics. The anti-fog film is available in standard nominal gauges from 7 to 30 mils (175 to 750 µm) and a width of 48 inches (1220 mm), suitable for very thin lenses as well as large face shields.

SABIC’s advanced new LEXAN™ HP92AF Anti-Fog film clearly extends the time-to-fog of  face shields and safety goggles for front-line workers in healthcare
SABIC’s advanced new LEXAN™ HP92AF Anti-Fog film clearly extends the time-to-fog of face shields and safety goggles for front-line workers in healthcare and other exposed environments.
Ahmet Kizilirmakli is the senior product manager of sheet and film for SABIC’s Functional Forms business unit in America. For more information, contact SABIC Functional Forms at 1 Lexan Lane, Mt. Vernon, IN 47620-9367 USA; phone (812) 831-7000 or (800) 323-3783, fax (812) 831-4955, ahmet.kizilirmakli@sabic.com or www.sabic.com/sfs.