Improving the ultraviolet protection factor of cotton fabric

The effects of cover factor, reactive dyes in pale and deep hues, double layers of fabric, and ultraviolet (UV) absorption on the UV Protection Factor (UPF) of a lightweight, bleached cotton fabric were investigated. UV transmission and reflectance were measured and the UV absorbency of the dyes was calculated. The undyed fabric provided low protection against UV rays in single and double layers. Application of monofluoro-s-triazine reactive dyes (particularly the deep red dye) increased the UPF. The effect of the UV absorber was most pronounced on the blank-dyed fabric. A double-layer of fabric with the blank-dyed fabric facing the source of UV radiation and the dyed layer facing the skin exhibits very good to excellent UPF.