Japanese automaker Nissan says it has developed a "cool paint” that can keep people inside cars cooler. But the company said the coating is six times thicker than usual auto paint, making commercialization still a challenge. Nissan's announcement Tuesday came as Japan was enduring record sweltering temperatures. Nissan tested the paint on vehicles scuttling around Tokyo’s Haneda airport, which has plenty of unshaded areas. The company said the cool paint cut the vehicles' roof-panel temperature by 12 degrees Celsius, or 22 degrees Fahrenheit. The interior was 5 C, or 9 F cooler. Cooler cars can reduce use of air-conditioning and reduce the toll from heat on engines and electric vehicle batteries.
