Chemists develop military camouflage face paint to ward off heat
Chemists have developed a new type of military camouflage face paint that could help protect from the heat of explosions and fires. The makeup could also be used by firefighters entering burning buildings to ward off heat.
Soldiers use camouflage face paint to help them blend in to their environment and hide from enemies. But the paints are typically mineral oil-based or mineral spirit-based and provide no protection from the heat of a blast. In fact, the paint can melt or burn, increasing damage to the soldier’s skin.
A team headed by chemist Robert Y. Lochhead of the University of Southern Mississippi in Hattiesburg took on a task that he initially viewed as impossible: developing a paper-thin paint that was nontoxic, colorable and provided protection against heat. He noted at a Philadelphia meeting of the American Chemical Society that the thermal heat wave from a blast reaches temperatures of 1,112 degrees Fahrenheit -- the temperature of a burning cigarette. The thermal blast lasts only two seconds or so, but in that time it can cook the face, hands and other exposed skin.
The team’s new makeup is based on silicones, which are less flammable than mineral oils because they absorb heat at different wavelengths. The team developed a formulation that could be colored with dyes that provide environmental protection to the soldiers. They also faced another challenge. Military specifications require that such face paints incorporate 35% of the insect repellent DEET, which is flammable. The team was able to minimize DEET’s ability to catch fire by incorporating it in a water-rich hydrogel substance that protects it from heat.
Laboratory experiments showed that the new makeup could protect skin for as long as 15 seconds before its temperature rose high enough to produce mild first-degree burns. In some tests, the paint provided protection as long as 60 seconds, Lochhead said, which could give soldiers time to escape from a blast zone.
The team will continue testing the product on skin, and will study its use for protecting clothing, tents and other material from burning. They are also developing a colorless version for firefighters.
