Who would have guessed that the solution to one of the biggest problems for a technophile would be simple candle soot? It may seem implausible, but researchers at the Max Planck Institute in Germany have indeed proven that the carbon residue released when burning a candle can be used to create a coating that is both oil and water resistant. Simply put, by making the screens on your mobile devices dirty with soot, you can keep them from smudged with fingerprints. Of course the process to make this happen is much more scientific then slapping a pile of soot on your device, so please don’t be rushing for your fireplace.
While the hurdle of liquid resistance in electronic screens is nothing new, no one has come up with a practical solution until now. A team from MIT has come the closest with an expensive form of nanolithographics that never gained footing because of the complexity and cost associated with it. By using a candle, the German research team has cleared said hurdle, with a caveat which we will cover later. The process they discovered is deceptively simple: By using the carbon residue from a lit candle, the team was able to coat a glass slide with black soot. While this substance is relatively sticky in itself, it can easily be washed off with a bit of elbow grease. The researchers decided to give the soot a coating of silica to protect it since the chemical makeup of the soot was not what they were after, but the way it created a rough surface on the glass at microscopic levels. From that point, the team baked the slide in an oven at 600C (1112F) which served to make the soot transparent. The result was a thin, cheap, clear coating that repelled both oil and water molecules while leaving the screen clean and dry, or “superamphiphobic” in scientific terms.
Pictured above is a 5-micrometer drop of solvent that has been dropped on this superamphiphobic surface. If you look closely you can see that it actually bounces off the treated area rather than breaking and spreading. Because of the rough surface created by the coated soot, the surface tension of the liquid is not broken allowing it to stay in droplet form. Unfortunately, though, as we mentioned, there is a caveat: The coating right now is very fragile — it can simply be scratched off a treated surface with a sharp object, rendering the whole process useless. Imagine putting a treated phone into the same pocket as a set of keys…
The Max Planck team will surely come up with a way to perfect their discovery, however, as there is simply too much money to be made with this breakthrough. It seems that putting another sealant on top of their current coating may do the trick.
The other applications for the soot coating are wide and varied. Imagine having a vehicle that needs no windshield wipers because the glass actually repels water. How about medical equipment thatcuts down on the chance of infection because their surfaces don’t allow germs to settle on them? This is a technology that we will definitely see in the future because of the availability of cheap commercial soot particles. Once the process has been perfected to where it can’t be scratched off, it will be the new standard much like Gorilla Glass has become.
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