Evaluation of Color Sensitivity to Dyeing Parameters in Natural Dyeing with Anthocyanin

as literature review shows it is possible to replace synthetic dyes with echo-friendly ones as natural dyes. Although plants exhibit a wide range of colors, not all of these pigments can be used as dyes directly. Sunflower seed is one of the popular vegetal cooking oil source used in Iran, as well as in the world. The main colorants in the sunflower seed hulls (SFSH) are anthocyanin. Anthocyanin dyestuffs are mainly used in food industry. Most of the purple, blue and black fruits are sources of anthocyanin. Anthocyanins can be used as pH indicators because their color changes with pH. The aim of this study is to understand firstly the SFSH useable source for textile dyeing and secondly the effect of dyeing bath pH, temperature and dye concentration on the woolen yarn properties. The range of color developed on dyed materials are evaluated in terms of (L*, a*, b*) CIE LAB coordinates and the dye absorption concentration on the woolen yarn dyed by SFSH is studied by using K/S values. Also fastness tests on dyed samples for light and washing fastness were carried out.
CIELab coordinates of the samples change in different dyeing processes. This could be explained with presence of anthocyanin components that are sensitive to pH and temperature. The study of the effects of different factors on dye ability of wool by SFSH extract showed that the pH and the temperature of dye bath considerably affected the color yield. The best results were obtained at pH 3.5 and boiling temperature.