Self Cleaning Textiles Becoming More of a Possibility
by Warren McLaren, Sydney on 06.17.08
Eighteen months ago we reported on the move to have perfluorooctanoic acid (PFOA) banned as a chemical that could leach into the environment. this helped spurred on developments to find alternatives. (PFOA is the stuff that makes teflon non-stick and Scotchgard treatments stain resistant.)
Several options are emerging in the category of textile protection. One is Schoeller Nanosphere technology, which said to be so efficient that the usual staining suspects "simply run off the nano-surface,” like the right hand image. Schoeller Textiles, a high tech Swiss materials company even has mini movies of honey, balsamic vinegar, wine, and coffee being repelled. Schoeller suggest that their finish, developed with Clariant, while taking inspiration from the famed lotus leaf is also eco-sensitive.
Specifically they believe the finish fixes to fabrics in such a way that it “cannot come adrift.” This is said to make it, “highly abrasion resistant and the protective function remains lastingly active, even when exposed to considerable load and after frequent washings.” Based on this, the company claim textiles with their NanoSphere finish can to be washed less frequently and at lower temperatures. “This leads to savings in the consumption of energy, detergents and water.”
Schoeller state that their product is considered free of PFOA and is certified by the Bluesign standard as being safe for humans.
Like Schoeller’s nanosphere finish, the US based Nanotex is also fluorochemical based. They too tout the lotus self-cleaning effect and have left-field videos, like a guy going for swim in a suit and tie and coming out mostly dry.
There is yet another finish with similar credentials known as GreenShield technology. However unlike the first two it is an inorganic nano treatment, not a fluorochemical. This particular variant on the theme has been successfully employed by Canadian firm, Victor-Innovatex. (They of the antimony-free polyester commercial upholstery.) This finish allows them to have their Eco-Intelligent materials certified as Cradle to Cradle products.
But all seem to work on the premise of having a microscopically small rough surface, so that water and oil molecules retain their inherent attraction bond and stay curled up in ball, rather than flattering out and spreading across a textile surface. (the top left image is a lotus leaf structure, the one underneath is the approximated nano structure.)
But, as the story of The Man in the White Suit foretold,
there may be a catch. in the self cleaning technology. Some are wondering if releasing nano-particles into the wild is akin to genetically-engineered agricultural crops. Could it be that once we release the Genie from bottle, we might lose the ability to put it back inside, should we not like what we find?
Images found in Schoeller website.
