The whitest white paint has been created after a strenuous 6-year process lead by Xiulin Ruan, a professor of mechanical engineering at Purdue University in West Lafayette, Indiana. Being labeled as the direct opposite of the 2014 infamous "Vantablack," this new feat in color production has more to it than what meets the eye.
Aside from being a standard acrylic-based substance, Ruan incorporated calcium carbonate pigment into the solution. The compound is commonly found in many everyday things, such as seashells and chalk. When ground down to microparticles, calcium carbonate can create a color whiter than any white that’s capable of reflecting more than 95% of all light hitting it.
A paint that can reflect more than 95% of light makes it naturally harder to absorb heat. So much so that it can make surfaces 18 degrees Fahrenheit cooler than they might otherwise be. And the implications of this paint used in urban areas can be very significant. "The first application we can think of is on the roof," Ruan says. The researchers have also estimated that a super-white painted housetop on a typical suburban home can save $1 a day in an electric bill during the summer.
"We looked at various commercial products, basically anything white," said Xiangyu Li, a postdoctoral researcher at the Massachusetts Institute of Technology, who worked on this project as a Purdue Ph.D. student in Ruan's lab. "We found that using barium sulfate, you can theoretically make things really, really reflective, which means that they're really, really white." The researchers' paint also contains barium sulfate, which aids the reflective nature of the color as it scatters light. Joseph Peoples, a Purdue Ph.D. student in mechanical engineering who took part in the research, believes that the paint could be more reflective if they were to assess the barium content further.
The researchers tested the paint on more than 200 different appliances and products that are white and believe that the ultra-cool color could hit the shelves sometime next year. With its ultra cooling capabilities, the new white could offer a cost-effective solution for more impoverished regions of the world that suffer from heat, as the paint will be much cheaper than air conditioning. The study was published in the American Chemical Society.