The fluorescence intensity of fabric whitened with FBA increased as the number of fabric layer increased, and reached to the constant value that was intrinsic to the sample fabric. The higher lightness of background used and the larger amount of FBA on fabric, the less effect of FBA on fluorescence intensity of fabric was observed.
The psychometric lightness L* of fabric in CIE colorimetric system was affected by fabric structure and not by the degree of whiteness with increasing the number of fabric layer. Psychometric chroma coordinates a*b* showed the various loci depending on a degree of whitening or blueing of fabric. For the fabric overdyed by FBA or processed blueing, a*b* linearly converged on the intrinsic point of the fabric. For the fabric whitened only with FBA however, b* maximum was determined at the region 2-4 layers before converging. The psychometric chroma coordinates a*b* mechanically measured by 2-4 fabric layers agreed with visual whiteness.
