Terephthalylidene Dicamphor Sulfonic Acid Ottimo Filtro UV Anti-age Terephthalylidene Dicamphor Sulfonic Acid description Terephthalylidene dicamphor sulfonic acid is a sunscreen ingredient that provides UVA protection. It is also known as ecamsule or Mexoryl XS. Related ingredients: Ecamsule Mexoryl SX