Abstract
This study identifies the effects of sodium sulfate and surfactants in the papain treatment of wool fabrics using L-cysteine and EDTA as activators. The research method involves the use of 2% L-cysteine and 7% EDTA as activators at optimal conditions, papain treatment of wool fabrics with the joint use of sodium sulfates and surfactants, and measurements of the weight loss rate, tensile strength, and whiteness. Results showed that for both 2% L-cysteine and 7% EDTA, the maximum papain activity appeared at 0.5% sodium sulfate concentration. In both cases, the papain activity was enhanced at sodium sulfate concentrations lower than 0.5%. In contrast, the papain activity declined at sodium sulfate concentrations higher than 0.5%. The joint use of EDTA with 0.5% sodium sulfate was proven to be very effective in improving the papain activity. The joint use of 2% L-cysteine with 0.5% sodium sulfate appeared slightly effective in improving the activity but resulted in excessive decrease in the tensile strength and whiteness, compared to improvement in the activity. The joint use of surfactants, in the case of L-cysteine, interrupted the papain activity and decreased the tensile strength regardless of the surfactant type and concentration. In the case of EDTA, however, the joint use with 0.1-5% non-ionic surfactants, 0.1-0.5% anionic surfactants, and 0.1% cationic surfactant appeared to improve the papain activity. The maximum papain activity was observed when 0.1% of surfactant was used, regardless of the surfactant type. The nonionic surfactant was the most effective in improving the papain activity.