The weird thing about dry cleaning is that it's actually a wet process, usually involving a chemical called "perc"—short for perchloroethylene. Aside from helping Ray Davis discover how many neutrinos are streaming out of the sun, perc is a notoriously nasty and regulated substance, exposure to which has been linked to kidney and liver diseases.
But what if you never had to dry clean your clothes with perc, or even wash them at all? What if they cleaned themselves by the power of the sun alone?
Walid Daoud, an assistant professor at the City University of Hong Kong is trying to do just that.
Since 2002, Dr. Daoud has been working with anatase titanium dioxide–a chemical normally found in sun screen and cosmetics. He coats a nano-thin (less than 100 nanometers) layer onto fabrics. Titanium dioxide is photocatalytic, meaning it causes oxidation in other substances when exposed to light.
Said in plain english: Get stain on shirt, leave shirt out in sun, stain degrades.
In a press release, Daoud stated he expects that the coating will increase prices to about 1.5 times the base cost of the clothing in which it's used. So that $10 shirt will cost $15 if it's treated. That could be pretty valuable on high-end items. Think about it: How much do you spend every year to clean your suits and evening gowns?
Currently, Daoud is experimenting on cashmere, because of how delicate it is. If it can work on expensive goat hair, the thinking goes, it'll work on anything.
However, it could be years before self-cleaning clothes come to market, and the doctor is still working on a way to address the health concerns of using anatase titanium dioxide. He also needs to find a way to increase the durability of the coating.
For more on the process, check this out:
Hero Image: Flickr User "telstar" (CC BY-NC 2.0)
Via: The Smithsonian