A chalk-based coating for cooling

Researchers at the University of Massachusetts Amherst have developed a chalk-based textile coating that reflects UV and near-infrared light, cooling the fabric.

The researchers developed a process to integrate calcium carbonate, a material found in limestone and chalk, and barium sulfate into the polymer, applied by chemical vapor deposition. The researchers tested the cooling abilities of treated and untreated fabric on a sunny day with temperatures higher than 90 F. They found the temperature underneath the treated fabric registered 8 degrees cooler than the ambient temperature in the middle of the afternoon, and there was a maximum 15-degree difference between the treated and untreated fabrics.

Yee also simulated the friction and impact of laundry detergent in a washing machine and found that the coating remained intact and retained its cooling ability.

This research was funded by the U.S. National Science Foundation, and the team’s findings were presented at an American Chemical Society meeting in August 2024.