Self-healing paint helps drivers out of a scrape

THE dread that grips every car owner when they pull into a parking space that is slightly too small could soon be prevented by an invention from Japan — a transparent vehicle body paint that repairs scratches on its own.

The encounter with a thorny rose bush, the swipe from a fingernail and even the ravages of an automatic carwash brush will no longer hold any fear for drivers. Within a few hours of the damage occurring, the paint will start to re-form itself over the scratch, and by morning the mark should have disappeared.

The Scratch Guard Coat comes courtesy of the car group Nissan, and will soon be making its debut on the notoriously narrow and scratch-prone roads of Japan. The Japanese company will be offering the special paint as an option on its X-Trail SUV before deciding whether to use the product on its range of cars.

The paint will be offered to customers prepared to pay an extra 52,500 yen (£251) on top of the standard price of the X-Trail, and its makers claim that it will continue to work for about three years. Because of Nissan’s corporate partnership with Renault of France, the product’s success in Japan could mean that the paint soon starts appearing on cars in Europe.

Even if the car is attacked with a Y10 coin — the Japanese vandal’s weapon of choice — the paint should be able to cope with the damage. Within about a week, a Nissan spokesman said, the paint will repair the scratch. “Of course, you could speed the whole process up by pouring some warm water over the affected area — that would probably repair it in a matter of minutes,” he added.

Carmakers have been trying for years to offer their customers some sort of reliable scratch-proofing: successes have been few and far between, and the conventional wisdom has been to develop harder grades of paint to give the surface a basic resistance. The Nissan approach, which it has undertaken with Nippon Paint, its supplier, will push research in the opposite direction.

The result is a transparent, synthetic resin, the high density of which means that it slowly flows back to fill any cut in its surface. The proposed thickness of the coating is about the same as a normal coat of paint, which means that it will repair scratches made to that depth. The paint has been designed to coat dark cars, but Nissan said that there was no reason why the technology could not be used on lighter hues.

Japan’s obsession with cleanliness has sent other corporations in a similar direction. Asahi Glass has produced a self-cleaning window, and Panasonic has produced an air-conditioner in which a miniature robot patrols, collecting dust.