Microwave Assisted Modulation of Vat Dyeing of Cellulosic Fiber: Improvement in Color Characteristics

The role of radiations in textile processing is gaining attention due to its low cost, energy effectiveness and eco-friendly process. This study is concerned with the improvement in modulation of microwave assisted vat dyeing of cellulosic fiber. It was found that radiation treatment of both cotton fabric and dye solution for 1 min gives good color strength, while for redox reaction, 2.5 g of NaHSO₃, 2 mL of CH₃COOH, and 1.5 mL of H₂O₂ are the optimized conditions which show it is a cost-effective tool. Good color strength was obtained at 65 °C for 1 h dyeing using 50 mL of optimal solution in dye bath at pH 9. Finally, ISO standards for color fastness to light, washing, rubbing and perspiration were applied at 0.5–2.5% of shade at optimal conditions which showed that microwave treatment has enhanced the color characteristics. Hence, the technique can successfully and easily be employed for surface modification of fabric for good quality dyeing with various classes of dyes.