Effect of OBAs and Repeated Launderings on UVR Transmission through Fabrics

The increasing incidence of skin cancer in the populations of Australia and North America provided the impetus for developing educational programs about the risks of sun exposure and for developing sunscreens and sun protective clothing. In an effort to develop better fabrics for sun protective clothing, scientists have completed many studies investigating various factors influencing ultraviolet radiation (UVR) transmission through fabrics. Little research, however, has focused on the effect of repeated home launderings on UVR transmission through fabrics. In this study, eight types of summer-weight fabrics were subjected to 20 home launderings using detergents with and without an optical brightening agent (OBA). Results showed that OBAs used in laundering improved the UVRblocking ability of cotton fabrics and cottonlpolyester blend fabrics, but not fabrics comprised entirely of polyester and nylon. The implication of the study is that a UPF rating determined for a new cotton or polyesterlcotton blend fabric can not only be maintained, but can be significantly enhanced by repeated laundering of the garment in a detergent containing an OBA.