Characterization and Evaluation of the Levelness Parameters of Natural Dyes on Natural Fabrics

Abstract

The objective of this paper is to establish a quantitative method to determine the levelness (L) of coloration by spectrophotometric measurements. Previously, the L of coloration is mainly evaluated by visual assessment. Hence, we are not able to produce quantitative L data because the visual evaluation of the same colored material obtained from different observers can be quite different. Color levelness is actually a description of the uniformity of color shade in different places of the fabric. It is a very important parameter for the quality of textile coloration, quality control, and communication between laboratories. Thus, this research work evaluates the L parameters by using different variables, including: a) three different natural fabrics; namely, wool, silk and cotton dyed with yellow natural dye from onion skins under the effect of different mordants, and b) three different natural dyes; namely, onion skins, turmeric and madder applied on wool fabric samples under the effect of different mordants. The obtained results show that dyed samples with the highest color strength (K/S) have the highest unlevelness (U) and the lowest color difference (ΔE) values (i.e. the highest light fastness). These results are obtained regardless of the fabric type or dye used.