Goodbye washing machine: self-cleaning cotton created

Posted by Emma Woollacott

Doing the laundry's about to get easier. Forget the whole washing part: all we'll need to do is peg our clothes out on the line or hang them over the balcony railing.

Two Chinese chemists say they've found a way to treat cotton that allows it to clean itself of stains, bacteria and smells when exposed to ordinary daylight.

Mingce Long and Deyong Wu of Shanghai Jiao Tong University and the Hubei University for Nationalities in China used a coating made from a compound of titanium dioxide - the white stuff used in everything from white paint to sunscreen lotions.

Titanium dioxide has been known to break down dirt and kill microbes when exposed to some types of light, and is already used in self-cleaning windows, kitchen and bathroom tiles, along with odor-free socks.

Butr while attempts have been made to extend this self-cleaning ability to ordinary fabrics, it hasn't been terribly practical. Self-cleaning cotton fabrics do a thorough job only when exposed to ultraviolet rays, and there simply isn't enough of that in ordinary sunlight.

But Long and Wu discovered that all this changes when the coating takes the form of nanoparticles made from a compound of titanium dioxide and nitrogen.

They've tested it with an orange dye stain, and discovered that it removes all trace. Adding more dispersing nanoparticles composed of silver and iodine made the technique work even better.

The coating remains intact through the process, they say, and even when clothes are washed.

Best not let the laundry pile get too high, though: there's no word on when the technology will make it into the stores.