Abstract: The functional fluorescent dye 5(6)-(4,6-Dichlorotriazinyl)aminoFluorescein was used for dyeing cotton fabrics. The effect of dye concentration and fixing temperature on the K/S value of dyed fabrics was studied. The changing of K/S value, the moving of reflectance curve and fluorescence emission spectra as the change of dyeing concentration were investigated, and the relationship among the max reflectance, fluorescent intensity and K/S value was discussed. The results indicated that as the dye concentration increased, the red-shifting of reflectance and fluorescence emission spectra of dyed fabric was found. As the K/S value keeps increasing, the maximum emission wavelength and the fluorescence intensity of dyed fabric increases first then starts to drop. When the dye concentration was 0.1% ( o.w.f ), the maximum reflectivity of dyed fabric can reach 130%.DTAF can greatly improve the anti-ultraviolet performance of cotton fabrics. When the dyeing concentration is equal to or greater than 1% (o.w.f), the UPF value of dyed fabric can reach 50 +.

Key words: DTAF , cotton fabric , K∕S value , reflectivity , fluorescence , anti-ultraviolet radiation