Researchers in Canada have developed the first permanent anti-fog coating, according to a study in the March issue of Applied Materials and Interfaces. They suggest that this development could be used indefinitely to eliminate the buildup of fog on eyeglasses, windshields, goggles and camera lenses.
Researchers at Laval University in Quebec City applied a polyvinyl alcohol compound to a series of glass surfaces. The polyvinyl alcohol coating allowed moisture to spread more uniformly across a glass surface instead of forming dispersed vapor droplets. To promote better surface adhesion, the researchers applied four successive layers of molecules, which also enhanced the coating’s durability.
The final result was a thin, transparent, anti-fog coating that did not alter the optical properties of the surface on which it was overlaid. And best of all, the specialized coating did not wash off even after 24 hours of water immersion.
“Existing anti-fog treatments don’t have these properties and won’t withstand washing, so the product application must be repeated regularly,” says lead author Gaetan Laroche, Ph.D., professor of sciences and engineering at Laval. “Our coating, on the other hand, is permanent.”
Negotiations are currently underway with a major eyewear company that is interested in obtaining a license for this technology.
Chevallier P, Turgeon S, Sarra-Bournet C, et al. Characterization of multilayer anti-fog coatings. ACS Appl Mater Interfaces. 2011 Mar;3(3):750-8.