Utilization of Nigerian mango (Mangifera indica L) leaves dye extract for silk fabric coloration: Influence of extraction technique, mordant and mordanting type on the fabric color attributes

Abstract

Abundance, sustainability and environmental awareness are the impetuses for increasing global interest in new shades of the plant as an alternative to hazardous synthetic dyes for industrial applications. The purpose of this study was to evaluate the potential ability of dye extracts from Nigerian mango leaves (MLs) (obtained through microwave (MW)-assisted and aqueous extraction techniques) to color silk fabric with a range of appealing shades (yellow to brown) generated through metal- and bio-mordanting processes. The effects of pH, contact time, and temperature were studied to determine optimum conditions for dyeing silk fabric in the MLs dye bath. The pH value of 3, contact time of 60 min, and dyeing temperature of 70 °C were found to be the optimum dyeing parameters. MW as a modern heating tool enhanced the yield, dye exhaustion (E), and color strength (K/S) of MLs dyed silk fabric by 46.31 %, 23.65 %, and 9.27 %, respectively. It also improved the color properties (shade, color coordinates, and fastness properties) of the MLs dyed silk fabric. The satisfactory affinity of unmordanted silk fabric for MLs dye extract was enhanced and found to be very good for metal-mordanted and excellent for bio-mordanted silk fabric. Excellent anti-oxidant activity and UV protection were obtained after MLs dyed silk fabric was bio-mordanted. The bio-mordants used in this study were sustainable and eco-friendly alternatives to toxic transition metals, which are often used as mordants for natural dyed textile apparel. The study established MLs dye extracts as non-toxic, abundant and sustainable coloring materials for dyeing silk fabric on an industrial scale.