2011-03-21

A Permanent Anti-Fog Coating

Gadgets, Mobile Phones, Tablets, all the cutting edge tech you'd expect. 

‘World’s First’ Permanent Anti-fog Coating Developed - Mobile Magazine


Foggy lenses cramp the style of skiiers, snowboarders, divers and the average eyeglass-wearer who steps inside a building on a chilly day only to find themselves momentarily blinded.

Anti-fog coatings on the market often require multiple coatings, or don’t work that well, leaving a swimmer’s goggles fogged within minutes in the pool.

But researchers from Quebec City’s Université Laval might have a solution. The researchers claim they have developed the world’s first permanent anti-fog coating. According to the researchers, just one application is needed to work on eyeglasses, windshields, camera lenses, ski goggles, dive masks – whatever has a transparent glass or plastic surface – forever.


 

First permanent anti-fog coating developed

 [...]
Researchers used polyvinyl alcohol, a hydrophilic compound that allows water to spread uniformly. The challenge was to firmly attach the compound to the glass or plastic surface. To accomplish this, researchers applied four successive layers of molecules, which formed strong bonds with their adjoining layers, prior to adding the anti-fog compound over this base. The result was a thin, transparent, multilayered coating that does not alter the optical properties of the surface on which it is overlaid. In addition, the chemical bonds that join the different layers ensure the hardness and durability of the entire coating.

"Existing anti-fog treatments don't have these properties and won't withstand washing, so the product application must be repeated regularly," notes Professor Laroche. "Our coating, on the other hand, is permanent."

Foggy glass. A new innovation could eliminate, once and for all, the fog on eyeglasses, windshields, goggles, camera lenses, and on any transparent glass or plastic surface.

ACS Publications

Research Article

Characterization of Multilayer Anti-Fog Coatings

Pascale Chevallier, Stphane Turgeon†, Christian Sarra-Bournet, Raphal Turcotte, and Gatan Laroche

ACS Appl. Mater. Interfaces, Article ASAP
Publication Date (Web): March 7, 2011


[...] Coating thickness was evaluated by profilometry, nanoindentation, and UV visible light transmission. The hydrophilic nature of the anti-fog coating was assessed by water contact angle (CA), and its anti-fog efficiency was determined visually and tested quantitatively for the first time using an ASTM standard protocol.  Results show that the PEMA/PVA coating not only delayed the initial period required for fog formation but also decreased the rate of light transmission decay. Finally, following a 24 hour immersion in water, these PEMA/PVA coatings remained stable and preserved their anti-fog properties.