ecamsule

Also called Ecamsule (technical name terephthalylidine dicamphor sulfonic acid), Mexoryl SX is a synthetic sunscreen agent developed and patented by L’Oreal and used in the company’s sunscreen products sold outside the United States since 1993 (approved for use in Europe in 1991). Ecamsule affords broad spectrum protection against the sun’s UVB and UVA rays. Exposed to UV, ecamsule undergoes reversible photoisomerization, followed by photoexcitation. The absorbed UV is then released as thermal energy, without penetrating the skin. The UVB range is 280 to 320 nanometers, and the UVA range is 320 to 400. Ecamsule protects against UV wavelengths in the 290–400 nanometer range, with peak protection at 345 nm.[3][4] Since ecamsule doesn't cover the entire UV spectrum, it should be combined with other active sunscreen agents to ensure broad-spectrum UV protection. Ecamsule is a photostable organic UVA absorber, meaning it doesn't degrade significantly when exposed to light. — NCATS