Researchers have developed clothes that clean themselves when exposed to a heavy dose of sunlight and water vapor. It starts with spraying a thin layer of Titanium Dioxide Nanocrystals on wool, silk and hemp. Once infused with the compound and heavily stained, the clothing is placed into UV light where the synthesis begins. The Titanium Dioxide turns into hydroxyl radicals and begin to oxidize, or eat away at the stain. Titanium Dioxide poses not threat to humans or the textiles, and is in fact found in toothpaste, paint, and sun screens. Depicted to the right is a red wine stain applied to a treated piece of wool. After a few hours the stain has disappeared. Titanium Dioxide is also known for destroying pathogens, making for a significant commercial opportunity in hospital bedding, gowns and other textiles.  No sun or UV light and the stain will remain.

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