Improvement of soil release from polyester fabric with atmospheric pressure plasma jet

Polyester fabrics were exposed to an atmospheric pressure plasma jet (APPJ) to improve their detergency performance. Surface characterization of the polyester fibers showed that wettability, surface free energy, and surface oxygen concentration increased after the APPJ treatment. The untreated and APPJ-treated polyester fabrics were soiled with carbon black, oleic acid, and stearic acid as model contaminants. The soiled fabric was washed together with the original fabric in the aqueous detergent solutions without and with mechanical action (shake or ultrasound). A washing test using a horizontal drum type washer in accordance with ISO 6330 was also performed to verify the efficiency of the APPJ treatment to polyester fabric in a domestic laundry. The soil removal from the fabric and redeposition onto the fabric were evaluated from the changes in the surface reflectance of the soiled and the original fabrics due to washing. As expected, the APPJ treatment was found to enhance soil removal and to prevent soil redeposition independent of detergent solution and mechanical action. When the polyester fabric after soiling was exposed to the APPJ, the increase in soil removal and the decrease in soil redeposition were remarkably observed compared with the APPJ exposure to polyester fabrics before soiling. Such detergency improvement by the APPJ was also observed for a cotton fabric soiled with stearic acid.