I have often dreamed about self cleaning glass, especially after spending an entire weekend cleaning each and every window in our home. My dream has turned into a reality; self cleaning glass actually exists. Pinch me, apparently, I wasn’t dreaming after all. I just had to dig a little deeper to learn how it works, and if it works at all.
What is Self Cleaning Glass?
Without getting to deep into the technical aspects of what it is, or how it is made; the short story is that self cleaning glass has an ultra thin coating of titanium dioxide on the exterior surface. How thin? About 20 nanometers! To put this in perspective, it would be the equivalent of placing a nickel on top of Willis Tower in Downtown Chicago.
How does Self Cleaning Glass Work?
The principle behind self cleaning glass is a little scientific. We all know, from our high school science class, that titanium dioxide is a photo-catalyst. Okay, you caught me, I didn’t know, I had to look it up. Anyway, a photo-catalyst is a material that generates a chemical reaction when subjected to light. In the case of titanium dioxide, the catalyst is ultraviolet light. When exposed to ultraviolet light the titanium dioxide generates electrons.
The electrons then turn the water molecules from the air into hydroxyl radicals which attack the organic dirt build up on the glass. By breaking the dirt up into much smaller pieces, it is far easier for the rain to wash off the contamination.
The Effect of Rain on Self Cleaning Glass
You’re probably wondering how the rain can clean self cleaning glass while not cleaning conventional glass in the same way? Since the chemical reaction takes place on the surface of the glass itself, the grime practically falls off the self cleaning glass on its own. The chemical reaction acts like a chisel to release the dirt and debris from the glass.
In addition, the surface of self cleaning glass is much smoother than conventional glass. This ultra-smooth surface is hydrophilic (loves water, so the droplets spread out, and are smaller) as opposed to standard glass which is hydrophobic (repels water and causes large droplets to form). This allows the rain water to sheet off the glass and evaporate rapidly, rinsing away the buildup of grime.
Self cleaning windows really do work. It’s simply incredible how clean they stay on their own, making them perfect for hard-to-reach window locations, not to mention tall office buildings. Cardinal Glass Corporation offers their own version of Self cleaning glass called “Neat Glass.” Learn more about Neat Glass here.
What will they think of next? How about a self cleaning car? Now that would truly free up my weekends. I can’t wait.