Comparison of sodium dithionite and glucose as a reducing agent for natural indigo dyeing on cotton fabrics

A traditional reducing agent in an indigo dyeing process with cotton fabrics is sodium dithionite (Na2S2O4) which is environmentally unfavorable because the resulting by-products cause various problems to the disposal wastewaters. In this research, glucose was used as a possible replacement of Na2S2O4 in indigo dyeing. The comparison of reduction power of Na2S2O4 and glucose for natural indigo dyeing on cotton fabrics based on reduction potential was analyzed. The optimum reduction temperature for natural indigo dye of both reducing agents was at 70°C. The reduction time did not have a significant effect on the reduction potential under the condition studied. Na2S2O4 could give higher color strength than glucose. However, wash fastness of the fabric samples from a glucose reduction was slightly better than Na2S2O4 ones. Hence, glucose virtually has a potential to be used as a green reducing agent in natural indigo dyeing

Comparison of sodium dithionite and glucose as a reducing agent for natural indigo dyeing on cotton fabrics

A traditional reducing agent in an indigo dyeing process with cotton fabrics is sodium dithionite (Na2S2O4) which is environmentally unfavorable because the resulting by-products cause various problems to the disposal wastewaters. In this research, glucose was used as a possible replacement of Na2S2O4 in indigo dyeing. The comparison of reduction power of Na2S2O4 and glucose for natural indigo dyeing on cotton fabrics based on reduction potential was analyzed. The optimum reduction temperature for natural indigo dye of both reducing agents was at 70°C. The reduction time did not have a significant effect on the reduction potential under the condition studied. Na2S2O4 could give higher color strength than glucose. However, wash fastness of the fabric samples from a glucose reduction was slightly better than Na2S2O4 ones. Hence, glucose virtually has a potential to be used as a green reducing agent in natural indigo dyeing

fabric

The concept of third-hand cigarette smoke is a newly-emerging field of interest in public health. Release of second-hand smoke chemicals on the textile surface as a third-hand smoke to the surrounding environment is a malodorous release of hazardous chemicals to health. In this study, the influence of MCT-beta-cyclodextrin treatments on not only the third-hand cigarette smoke odor release property but also on the mechanical and dyeing performances of cotton fabric was investigated. MCT-beta-cyclodextrin treatments increased the stiffness and tensile strength of cotton fabric. The presence of MCT-beta-cyclodextrin on cotton fabric did not significantly affect the dyeing properties and caused no profound effects on the obtained color strength levels on fabrics dyed with Drimarene reactive dyes. MCT-beta-cyclodextrin treatment resulted in a significant reduction of the third-hand smoke odor release intensity from the smoke-contaminated cotton, for both dyed and undyed fabrics. The reactive dyes resulted in a positive influence on the third-hand smoke odor release intensity. MCT-beta-cyclodextrin presence on the dyed fabric enabled a significant decrease in odor and produced a masking effect with an odor release reduction of up to 65.5%. Inclusion complex between the beta-cyclodextrin rings and the volatile organic compounds of the cigarette smoke is believed to be a smoke odor chemical trapping mechanism. MCT-beta-cyclodextrin treatment effectively masks chemical malodors from second-hand cigarette smoke and lessens the third-hand smoke odor chemical release onto cotton fabric. Therefore, MCT-beta-cyclodextrin treatment may lessen the potential health hazards of third-hand smoke released from the contaminated textile surfaces. This is promising and encouraging for odor emission control and third-hand smoke release problems for smoke-exposed textile products

Investigation of UV protection, self-cleaning and dyeing properties of nano TiO2-treated poly(lactic acid) fabric

Investigation of nano TiO2 treatment on poly(lactic acid) (PLA) fabric was conducted in this study. The treatment conditions were found to be optimal at 130°C with 20 g/L acrylic binder. Nano TiO2 exhibited a positive influence on UV protection and self-cleaning properties of PLA fabric. The degree of UV protection expressed as ultraviolet protection factor values of PLA fabric increased with nano TiO2 concentration. Moreover, self-cleaning property was also imparted to PLA fabric. The photodegradation of methylene blue stains was observed on the treated fabric. The stain fading percentage increased with nano TiO2 concentration. Nano TiO2 was also found to enhance the dyeability of PLA fiber when dyed with C.I. Disperse Red 60 and Violet 33 dyes. Higher colour strength was obtained on the nano TiO2-treated PLA fabric. Dyeing the nano TiO2-treated PLA at the boiling temperature was also compared with the untreated and dyed PLA under typical dyeing conditions. © 2016, Chemical Publishing Co. All rights reserved