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How Self-cleaning Paint Works


Nano-what?
Nissan Europe has begun tests on innovative paint technology that repels mud, rain and everyday dirt, meaning drivers may never have to clean their car again.
Nissan Europe has begun tests on innovative paint technology that repels mud, rain and everyday dirt, meaning drivers may never have to clean their car again.
(Courtesy of Nissan)

As we mentioned, it takes some specialized knowledge to create a coating that can repel environmental contaminants. In tech circles, this paint is known as a nano-coating, and it's just one of many products that are the result of nanotechnology. Nanotechnology is an entire industry that revolves around the study of (and engineering of) nanoparticles, which are particles of elements that are so small, they have to be created in a lab. Once these nanoparticles are created, they have some really unique properties -- especially in terms of how they react with ordinary particles. They've been used to create clothing that can reduce air pollution on contact, and they've even been added to products like sunscreen.

Nissan is the first auto manufacturer to put a nano-coating on a car, though, and they went straight to the source. The car company worked directly with Nano Labs, which was the first manufacturer to use nanotechnology to create a self-cleaning paint. Nano Labs has only been around since October of 2012, but it already has plenty of experience with the relatively new technology. The automotive version of the paint is called Ultra-Ever Dry, and it's based on coatings that are sold for industrial and commercial uses. Other versions of this industrial coating -- those made by other manufacturers -- were inspired by the leaf of the lotus plant, which has a surface that sheds dirt along with rainwater. This is where nanotechnology comes in -- the engineers who designed the paint figured out how to minimize the surface area where water and dirt cling, which helps the water and other contaminants run right off. Of course, this happens at a level that can't be seen, but the effects are definitely noticeable. If you want to get picky, a nano-coating isn't really self-cleaning. To be more accurate, it simply repels the types of contaminants that would make it need to be cleaned, like water and oil. On a building, graffiti is an obvious and common cause of frequent washing. On a car, it's more likely to be dirty rainwater, mud, or bird droppings. Nissan says that its water-repellent properties will prevent snow, ice and frost buildup by maintaining a layer of air between the top of the paint's surface and whatever touches it -- and Nano Labs says that its nanotechnology approach yields a less expensive product than other coatings that rely on surface tension.


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