Application of Vat Green 1 dye on gamma ray treated cellulosic fabric

• The optimal absorbed doses for surface modification of cotton are 6 kGy.
• Irradiation has reduced the amount of chemicals needed.
• Optimal dyeing conditions are 75 °C, 60 min and pH 11.
• Optimal quantity of sodium hydrosulphite is 1.2 g and of H2O2 is 1.2 mL.
• At optimal conditions, colour strength and fastness properties are enhanced.

For the present study, Vat Green 1 dye has been selected for dyeing gamma irradiated cellulosic fabric. The dyeing variables such as dyeing temperature, dyeing time and dyeing pH were optimized. Concentrations of sodium hydrosulphite for reduction process and hydrogen peroxide for oxidation process were also optimized. After evaluation of dyed fabrics in a CIE Lab system using Spectraflash SF-650 it has been found that 6 kGy is the effective absorbed dose for improvement in dyeing behaviour of cellulosic fabric. Good colour strength has been obtained by dyeing optimal irradiated fabric (6 kGy, IC) at 75 °C for 1 h. by employing dyeing solution of pH 11. It has also been found that gamma ray treatment has reduced the necessary quantity of reducing (NaHSO3) and oxidizing agents (H2O2). The rating results after implementation of suggested standard methods of ISO for colourfastness showed that using irradiated textiles, the fastness to light, washing and rubbing has been significantly improved.