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Natural dyes are gaining interest due to their expected low risk to human health and the environment. A source of natural dye was found in industrial operation of steaming Eucalyptus grandis wood. The liquid waste generated at the end of the process has been discarded. Due to this fact and the intensity of the color of the product, it was emerged the idea of this study, considering natural dye for textile fabrics. The waste was used for dyeing cotton, nylon and wool by exhaustion dyeing process. The effects of the dye concentration, the application in liquid and powder form, time, temperature, pH of the dyeing bath and the addition of metal salts in the bath were evaluated. The physic-chemical characteristics of the waste as pH, color, thin layer chromatography, and total solids and condensed tannins were also investigated. The resulting dyed fabrics were evaluated for color fastness to light, domestic washing and rubbing. The waste showed brown color, acidic pH, average total solids content of 2.2% and content of condensed tannins of 0.93%. The results from thin layer chromatography of the residue suggested the presence of tannic acid in its composition. Regarding the color fastness, it was found a very good result considering domestic washfastness, with lightfastness typical of natural dyes. The rubbing fastness was good, especially for cotton, which presented excellent grades. It was possible to consider the liquid residue as product potentially destined to the textile industry, regarding the natural dyeing of cotton, nylon and wool.

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