Abstract
This paper describes the results of the laboratory test to investigate the effects of the fluorescent brightners contained in the detergents for domestic laundry on the visual appearance of dyed fabrics. Cotton shirtings, dyed with disperse dyes in red, yellow and blue of three different levels in saturation and lightness, were treated with the fluorescent brightners of 0.1, 0, 5 and 1.0% owf. They were then exposured under carbon-arc light of a weather-O-meter. Such treatment/exposure cycles were repeated by eight times. The degree of saturation, reflectance of fluorescent light and visual appearance were determined after each treatment/exposure cycle. The following two results have been obtained :
(1) The reflectance of fluorescent light depends on the concentration of the fluorescent brightners and spectral reflectance of wave-length where fluorescent light were emitted.
(2) The fluorescent brightening treatment decreases itse effect with repeating treatment/exposure cycle. The lowering of saturation injures the visual appearance of dyed fabrics.
