Dyeing of Shoe Upper Leather with Extracted Dye from Acacia Nilotica Plant Bark-An Eco-Friendly Initiative

Document Type : Original Article


1 Department of Leather Engineering, Institute of Leather Engineering and Technology, University of Dhaka, Dhaka, Bangladesh

2 Department of Leather Products Engineering, Institute of Leather Engineering and Technology, University of Dhaka, Dhaka, Bangladesh


In recent years, the application of non-toxic and eco-friendly natural dyes for textile and leather coloration is getting interest among manufacturers and buyers due to the hazardous impact of conventional azo dyes. Natural dyes have extensive use in textiles, yet their application to leather is very limited. In this research, the prospect of using dye extracted from Acacia nilotica bark for dyeing of shoe upper leather was examined. Chrome-tanned goatskins were employed as raw material for dyeing with the extracted dye using drum dyeing method. The dyeing process was conducted with and without mordant, following pre-mordanting and post-mordanting techniques. Color analysis, various colorfastness tests, and determination of dye exhaustion rate were conducted to evaluate the dyeing quality. It was observed that the experimental dye imparted amber color to the leather that turned brown and gray upon mordanting with potash alum and ferrous sulfate, respectively. The dyed leather samples showed excellent colorfastness but moderate heat and light fastnesses. Mordanted dyed samples, especially the prr-mordanted dyed samples, possessed a better color intensity and more dye exhaustion rate. The leather samples dyed with extracted dye also increased the strength property of the leather and various color shades were produced by mordanting techniques. 


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