Environment and energy efficient dyeing of woollen fabric with sticta coronata

For a trial to improve the natural dyeing cultural heritage to meet the environmental future demands technology to reach high quality dyed patterns. This paper deals with extraction, dyeing of woollen fabric with “Sticta Coronata” under ultrasonic energy and glucose/hydrogen peroxide based redox system. The efficiency of ultrasonic-assisted extraction in presence of 9:1 water:acetone solvent and dyeing in presence of redox system, followed by alum mordanting have been studied in compared when the system was absent and the traditional thermal technique. The influence of redox system, ultrasonic energy and alum mordanting on the rate of dyeing and dye fixation has been demonstrated, and the mechanism of glucose/hydrogen peroxide redox system has been tentatively suggested. The extraction with 9:1 water:acetone solvent possesses higher absorbency in shorter extraction time compared with the aqueous one. Redox system reduced the rate of dyeing at lower temperature with significant enhancement on the dye exhaustion and fixation, involving covalent bonding in addition to the usual coulombic bond. Mordanting process exhibited negligible effect and might decline the percentages of dye exhaustion and fixation in presence of redox system. Ultrasonic energy provided easy efficient route for dye extraction, dyeing, and mordanting processes in compared with the traditional thermal technique.