ASSESSMENT OF THE DYEING PROPERTIES OF LAWSONIA INERMIS ON MULTIPLE FIBERS USING THE EXHAUST METHOD

Abstract

Natural dyes are environmentally friendly, biodegradable, hypoallergenic, and non-toxic, offering a sustainable alternative to synthetic dyes that often cause water, soil, and air pollution as well as skin irritation and toxicity. In this study, Lawsonia inermis (henna) leaves were used to extract a natural colorant traditionally applied for body art during cultural and festive events. Metallic mordants—copper sulfate (CuSO₄), ferrous sulfate (FeSO₄), and ferric chloride (FeCl₃)—were used to alter the dye’s hue, and the dyeing process was conducted on multi-fiber fabrics using the exhaust method. The multi-fiber fabric, comprising cotton, cellulose acetate, polyacrylonitrile, polyamide, polyester, and wool, enabled assessment across various textile types.

The dye extraction was carried out in an aqueous medium at room temperature (30 ± 1 °C). Evaluations included color fastness, color strength (K/S), washing fastness, percent reflectance, and color coordinates (CIELab*) under both acidic and alkaline conditions. In this color space, L* represents lightness, while a* and b* correspond to the red–green and yellow–blue axes, respectively. Color strength (K/S) was measured using a colorimeter under D65/10° and TL84/10° light sources. After washing, an increase in L* and b* values and a decrease in a* were observed, indicating a shift toward lighter, more yellowish tones. Overall, the results demonstrated that dyeing in an alkaline medium produced superior color strength and fastness compared to acidic conditions. Notably, cellulose acetate, cotton, and polyamide fibers exhibited excellent light fastness.