Ammonia ligand and transition metal salt complexation on naturally dyed textile surface: A reflectance spectroscopic investigation to understand coloration and fastness properties

Ammonia is a stronger ligand and can replace water molecules in a chelate metal complex as per spectrochemical series. This property of ammonia was utilized in this work for the coloration of wool in order to obtain some unusual effects. Different concentrations of ammonia solution was applied on Butea monosperma flower extract dyed wool previously premordanted with ferrous sulfate salt to evaluate the effect on colorimetric properties. A range of newer shades were produced on wool substrates which were characterized in terms of K/S, CIELa*b* values and fastness properties. The observed effects exhibited on wool and acceptable fastness properties of produced shades points out a promising approach for developing environmentally sustainable colorful textile materials and clothing. The chemical modification of wool before and after application of ammonia was also evaluated using Fourier transform infrared spectrometer analysis. © 2019 American Institute of Chemical Engineers Environ Prog, 38:e13146, 2019