Colouration and bio-activation of polyester fabric with curcumin in supercritical CO2: Part II - Effect of dye concentration on the colour and functional properties

This study presents a sustainable approach to the fabrication of multifunctional polyester fabric with bioactive natural colourant curcumin through a water free supercritical CO2 dyeing technique. A simple dyeing process was carried out in which curcumin powder dye was directly applied to polyester fabric in scCO(2) medium without involving mordant chemicals and fabric pre-treatment procedures. The colour, bioactivity, and durability properties of the dyed samples were characterized. Results showed that the colour strength increases when the dye concentration increases and higher colour strength (K/S value above 17) could be achieved using low curcumin concentration (ca. 0.75 % owl). Moreover, the dyed fabrics displayed desirable antimicrobial, antioxidant, and UV-protection activities with acceptable colour fastness to washing and rubbing. This study opens a new view towards the sustainable fabrication of coloured and bioactive polyester fabric using curcumin via a resource-efficient and eco-friendly scCO(2) dyeing technique. (C) 2019 Elsevier B.V. All rights reserved.