Performance enhancement of non-toxic and bio-based textile finishes through novel and sustainable ozonation

Most effective and durable finishes for cotton fabrics typically contain toxic and sometimes carcinogenic chemicals. Although certain bio-based alternative finishes have been reported in literature but these alternatives are usually less effective than conventional toxic finishes. To improve the performance of bio-based finishes, this paper develops and improves a novel and ecofriendly finishing process for 100% cotton fabric, based on ozone treatments in very controlled amount for the first time. Four types of bio-finishes including citric acid, stearic acid, diammonium hydrogen phosphate and fatty acid amide, for easy care, water repellency, fire retardancy and softness properties respectively were used in this research. For each finish, three ozone-based finishing processes; pre-ozonation, in-situ ozonation, and post-ozonation were developed and optimized. For all four types of bio finishes, fabrics with 20% post ozonation exhibited superior finish performance. Crease recovery angle increased from 121° to 194°, water repellency rating improved from rating 0 to 90, char length decreased from 26.6 cm to 10.8 cm and bending length decreased from 2.16 mm to 1.1 mm by using bio-based finishes with ozone exposure without compromising mechanical and comfort properties of cotton fabrics. SEM, FTIR and XRD analysis were also performed on ozone exposed and finished fabrics.