Their objective was to produce a paint colour that would help save energy and protect the environment from global warming. If sunlight can be efficiently reflected off a building's surface, it will noticeably affect the amount of energy being used to cool that structure. In other words, the more light that can be bounced back into space lessens the need for air conditioning. Scientists at Perdue University eventually achieved that goal and in doing so, stumbled upon something else – they created the whitest acrylic paint known to exist.
The pigment they developed cools a surface to a lower temperature than its surrounding environment. Current heat-resisting white paints reflect 80-90% of sunlight, but they do not have substantive cooling powers. Xiulin Ruan, a professor of mechanical engineering at Purdue, says that the formulation that his lab created reflects 98.1% of solar radiation while also emitting infrared heat. This is accomplished, in large part, by using high concentrations of the chemical compound barium sulfate.
As you might expect, this news has caught the attention of artists wishing to sample the ultra white paint. Ruan estimates that it will take up to two years to perfect a product that is ready for the market. However, he believes the pigment will be as affordable as acrylic white paints found in stores today, possibly even cheaper.