Photodegradation of human hair

Abstract

The role of moisture in photolysis of hair was investigated in this research. Melanin-free Piedmont hair was exposed to simulated sunlight at different humidity levels. Changes in wet mechanical properties, swelling behavior, and IR spectrum were used to determine the degree of damage. Weathering damages hair under all conditions of relative humidity during exposure, with exposure at 30% RH causing the least damage. A free-radical mechanism is used to explain the photolysis process.