Advancing SDG 12 through eco discharge printing

This research investigates the potential of eco-discharge printing using acid cellulase enzyme as a sustainable alternative to conventional chemical discharge methods, aligning with the objectives of Sustainable Development Goal 12 (SDG 12) Responsible Consumption and Production. The study focuses on five natural dye shades, green, brown, red, blue, and dark blue, applied to modal fabric, a regenerated cellulosic textile known for its eco-friendly production. An experimental approach was employed to optimise the discharge print recipe by systematically varying key process parameters: pH, temperature, enzyme concentration, and time. Discharge-printed samples were evaluated using a spectrophotometer to determine the degree of colour removal and visual clarity. Among the tested shades, green and brown demonstrated good discharge results, with clearly defined print edges and minimal background staining. Traditionally, white discharge printing on dark-coloured backgrounds has relied on chemical agents like sodium formaldehyde sulphoxylate, which, although effective, pose serious environmental and health hazards due to the release of toxic sulphur-based compounds and formaldehyde in effluents. In contrast, the enzymatic discharge method using acid cellulase was found to be effective and eco-friendly. The optimally discharged samples in green and brown shades were further evaluated for tensile strength and fabric hand, confirming that the enzyme-based process maintained the mechanical and tactile properties of the fabric. Moreover, Chemical Oxygen Demand (COD) testing of the wastewater from the optimised enzymatic recipe showed emission levels within permissible environmental limits, highlighting its potential for safer industrial application. The study successfully demonstrates that acid cellulase enzyme can overcome the limitations of conventional chemical discharge agents in selected natural dye shades. By reducing the use of hazardous chemicals, minimizing water pollution, preserving fabric quality, and ensuring safety for both artisanal health and wearer skin contact, this method provides a viable pathway for advancing SDG 12 targets, particularly through sustainable resource management, cleaner production practices, and responsible textile design.