Multifunctional finishes on photochromic microcapsule-printed cotton fabrics using titanium oxide nanoparticles

Abstract

Purpose This paper aims to study the combination of photochromic microcapsules, which use the ultraviolet (UV) rays for colour changing phenomena, and titanium oxide (TiO2) nanoparticles (NPs), which block the UV rays by their photocatalytic activity in the sunlight on the cotton fabric. Design/methodology/approach The TiO2 NPs mixed with photochromic printing paste are used for coating on cotton fabric and further curing is performed in a one-step process. The photochromic pigment printed fabric impregnated in a liquid solution is processed in a two-step process with two variables such as 1% TiO2 and 2% TiO2. The characterization of samples was done with a UV transmittance analyser, surface contact angle, antimicrobial test and fabric physical properties. Findings The UV protection of TiO2-treated photochromic printed fabric was high and gives the ultraviolet protection factor rating of 2,000 which denotes almost maximum blocking of UV rays. The antibacterial activity of the one-step samples shows the highest 36 mm zone of inhibition (ZOI) against S. aureus (gram-positive) and 32 mm ZOI against E. coli (gram-negative) bacteria. The one-step sample shows the highest static water contact angle of 118.6° representing more hydrophobicity, whereas the untreated fabric is fully wetted (0.4°). In two-step processes, as the concentration of TiO2 increased, the antibacterial activity, UV blocking and hydrophobicity became better. Originality/value This work achieves the multifunctional finishes by using photochromic microcapsules and NPs in a single process as a first attempt. The results inferred that one-step sample has achieved higher values in most of the tests conducted when compared to all other sample.