Nissan is developing cool paint for cars to keep drivers cooler

Nissan Motor Co. on Aug. 6 showed off a so-called "cool paint" that can keep people inside a car cooler, though the coating is six times thicker than regular paint, but commercialization remains a challenge.

The company's announcement is timely as Japan is experiencing record-breaking hot weather.

Nissan Motor Co. tested the paint on vehicles driving fast around Tokyo's Haneda Airport, where there are many places without shade, making it a good place to evaluate the technology. The vehicles painted with the special paint look the same as regular cars, but they feel much cooler to the touch.

Nissan said the cool paint can reduce the temperature of the car roof by 12 degrees Celsius and the temperature inside the car by 5 degrees Celsius.

Cooling materials are already widely used in buildings and other objects. Cooler cars can reduce the use of air conditioning and reduce heat loss from engines and electric vehicle batteries.

Toyota Motor Co. has also been experimenting with paint that can cool the cabin, focusing mainly on colors that reflect the sun's rays.

Nissan's cool paint reflects sunlight better while also generating electromagnetic waves that block the rays, transferring energy away from the vehicle.

Nissan's paint was developed by Chinese company Radi-Cool, which has developed a film, fabric and coating that insulates against heat. Radi-Cool also partners with several other Japanese companies to offer cool hats and parasols. Nissan is the only Japanese automaker to partner with Radi-Cool.

Susumu Miura, manager of Nissan's research center, said the electromagnetic waves emitted by the paint have no apparent negative impact on human health. Such electromagnetic waves are found all around us, he said.