Sustainable Dyeing and Finishing of Cotton Fabrics with Layer-by-Layer Technique

Abstract

Large amounts of water, synthetic dyestuffs and chemicals are used in the wet processes of textile finishing, and at the end of these processes, liquors containing chemical substances create a waste load. For this reason, it is of great importance to develop new wet-finishing processes that use less water, dyestuffs and chemicals. For this purpose, the layer-by-layer deposition method (LbL) was used in this research as an environmentally friendly, sustainable method that can be used in wet-finishing processes to minimize chemical, water and energy consumption. The dyeing and functional finishing of cotton fabrics were carried out in one process by the LbL method. Cotton fabrics were pre-treated with a commercial cationic dye fixation agent and cationic charges were produced on the fabric surfaces. Reactive and direct dyestuff groups were used in the dyeing process of cotton fabrics and fluorocarbon was used in the functional finishing process. Eight and 12 dye/fluorocarbon layered structures were obtained by LbL deposition using a laboratory-type padder. Cotton fabrics were dyed and finished with the same dyes and fluorocarbon via the padding method and both samples were compared. The washing, rubbing and light color fastness properties, color strength and color difference of the dyed samples were tested. Tensile strength, air permeability, SEM graphs, contact angle, water and oil repellency analyses were performed for the treated fabrics.

Mass production of carbon nanotube fibers and hybrid yarns for high-performance helical auxetic yarn strain sensors

“…The strain sensor was processed for 10 min at different temperatures (−200 °C,−20 °C, 28 °C, 50 °C, and 90 °C) and different pH levels (pH = 5, pH = 6, pH = 7, pH = 8, and pH = 9), and then the resistance changes before and after processing were measured. Conduct multiple water washing tests on the strain sensor according to the ISO 105-C10:2006(C) and related literature [35], and measure the change in resistance value before and after washing. Simply put, the samples were washed with 5 g L −1 nonionic soap solution (with a liquor ratio of 50:1) at 50 °C for 45 min, they were then rinsed and dried for 5 cycles.…”

An Overview of the Available Water Textile Effluent Treatments

“…As prevention, the sustainability measures intend to improve processing methods minimising water usage during wet processing, and lowering water consumption and wastewater effluent. As a result, methods such as anhydrous supercritical dyeing, solvent dyeing, dyeing with liquid ammonia, and reverse microemulsion dyeing methods (Varadarajan and Venkatachalam, 2016), (Lara, Cabral and Cunha, 2022), (Kabir et al, 2019) enzymatic treatments, (Sen et al, 2021) layer by layer techniques (Uğur, 2023) and foam dyeing (Mohsin and Sardar, 2019) have been reported. Some of these technologies are yet to be commercialised and remain in laboratory practice.…”