Cotton fabric is a woven or knitted textile built from twisted cellulose fibres, and it remains the most widely used apparel substrate. Its properties come from the fibre structure: the lumen and the convolutions give moisture uptake and a soft hand, while the crystalline cellulose provides strength ^[1]. The natural waxes and pectins on the raw fibre must be removed by scouring and bleaching before dyeing, and the finishing sequence determines the final whiteness and absorbency ^[2]. Functional finishing adds flame retardancy, antimicrobial behaviour, or water repellency, usually at the cost of tensile strength because the treatment also attacks the cellulose chain ^[3]. Grafting monomers onto the fibre surface is an alternative that leaves the bulk structure largely intact ^[4]. Durability of the finish to repeated laundering, rather than the initial performance, is the property that most often fails ^[5].