Consumer Science

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Browsing Consumer Science by Subject "Anolytes"

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    Anolyte as an alternative bleach for cotton fabrics
    (University of the Free State, 2015-01) Seiphetlheng, Kgalalelo; Steyn, H. J. H.
    English: Bleaches are used in the textile industry for brightening, whitening and cleaning fabrics. The two commonly used bleaches are hypochlorite and peroxide bleaches. Peroxide bleaches are used more often than chlorine bleaches in fabric finishing. Chlorine is a harsh chemical harmful to human health and may even destroy the cotton fibre if not monitored. It destroys the cellulose and that affects the quality of the bleached fabric. Large amounts of these bleaches are released into the environment through washing and they harm the environment and ozone layer. Hence, new and better ways of bleaching needs to be investigated. Electrochemically activated water (Anolyte) has been recently introduced to the food industries as a disinfecting agent. Disinfection with Anolyte has been successful and convenient because Anolyte is generated onsite by simple electrolysis of a dilute salt solution. The production of Anolyte requires lower production cost and hazards associated with handling, transportation and storage. Anolyte is stable and after 48 hours the solution become inactive water and can be discarded without causing harm to the environment. Although Anolyte has been successful in the food industry, extensive research has not been done to determine whether it can be used in the textile industry. The aim of this study was to investigate the effectiveness of Anolyte as a bleaching agent compared to the commonly used sodium hypochlorite. Distilled water was used as control. The efficacy of Anolyte was determined at 24°C 30°C, 40°C, 60°C and 80°C. The effect of Anolyte and sodium hypochlorite on bleached cotton, unbleached cotton, dyed cotton and stained cotton respectively were evaluated in terms of tensile strength, stiffness and whiteness. Further investigations were done on the effect of bleaching temperatures mentioned above and duration of exposure ranged from 9 minutes, 18 minutes, 30 minutes, 45 minutes, 60 minutes, 90 minutes and 120 minutes. The study was an experimental research where bleaching of samples was done according to AATCC Test Method 61- 2009 carried out in the Launder-Ometer. Reactive red dyed cotton, vat blue dyed cotton, bleached cotton and unbleached cotton were laundered for 5, 10 or 20 cycles respectively for the evaluation of the influence on tensile strength, stiffness and colour change. The tensile strength tests were conducted with the Instron Tensile Tester and ISO/SANS 13934-1:1999 test method. The stiffness test ASTM D1388 – 08 the Cantilever principle was used. While AATCC test method 135-1985 for instructional colour measurement of textiles was used in determining colour change. 169 The results gathered from the study indicated that Anolyte was less effective than sodium hypochlorite as a stain remover for blood, tea, soot/mineral oil and blackcurrant juice. Anolyte caused more colour loss on coloured materials than sodium hypochlorite especially at high temperatures. Anolyte was less effective in bleaching unbleached cotton than sodium hypochlorite but without harming the tensile strength of the cotton. Although Anolyte caused dyed cotton to lose colour, the stiffness of the dyed cotton was less than that bleached with sodium hypochlorite, making the cotton fabric to be much softer and desirable. It was also gathered that sodium hypochlorite reduced the tensile strength of vat blue dyed cotton and bleached cotton more than Anolyte. However, Anolyte on the other hand reduced the tensile strength of reactive red dyed cotton more than sodium hypochlorite.
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    ItemOpen Access
    Evaluation of the antimicrobial effect and strength properties of polyester, polyester/cotton and cotton treated with Anolyte
    (University of the Free State, 2011) Vermaas, Jana F.; Steyn, H. J. H.; Hugo, C.
    English: Textile materials are usually treated with chemicals like sodium hypochlorite and high temperatures to ensure sterility. This poses two potential problems: (1) it has a negative effect on strength properties of the textile fabric; (2) the harmful chemicals are discarded into the environment. Therefore, better and safer methods need to be investigated. A process has been developed where electro-chemically activated water (Anolyte) is produced by an anode-cathode system and the process is described as a change of the molecular state of the water. After production, the Anolyte exists in a metastable state while containing many free radicals and a variety of molecules and a very high oxidation-reduction potential. It returns to a stable state after 48 hours and become inactive again and, therefore, it is not a threat to the environment when discarded after use. Anolyte has been shown to be an effective disinfection agent in other areas such as the food industry. The aim of this study was to determine if Anolyte could reduce E. coli and Staph. aureus on textiles to the same extent as sodium hypochlorite and be effective without implementing such high temperatures. The influence of the Anolyte on textile material should also be evaluated to ensure that it could be used without damaging textile materials more than the currently used disinfection agents. The antimicrobial effect of the Anolyte was determined by contaminating cotton, polyester and polyester/cotton fabric swatches with E. coli and Staph. aureus, respectively. Survival was determined after laundering with the respective wash liquors. AATCC Test Method 61- 2009 was used with the LaunderOmeter. Wash liquors included filtered water, phosphate reference detergent B, sodium hypochlorite and Anolyte. Temperatures were maintained at 24, 30 or 60°C. The cotton, polyester/cotton and polyester were laundered for 5, 10 or 20 cycles respectively for the evaluation of the influence on tensile strength and tearing strength. The tensile strength tests were conducted with the Instron Tensile Tester and ISO/SANS 13934-1:1999 test method. The tearing strength tests were conducted with the Elmendorf Tearing Strength tester as per ASTM Test Method D 1424 - 63. The results indicated that Anolyte destroyed all E. coli and Staph. aureus on all the fabrics regardless of the temperature. The effect of the other agents were enhanced by the increasing temperature, but after laundering at 60°C no survival was found as a result of the high temperature. The Anolyte did not influence the strength properties of the cotton, polyester and polyester/cotton fabrics to a larger extent than the detergent or sodium hypochlorite solution. An increase in maximum load required to break the fabric and displacement at maximum load was found for the cotton and polyester/cotton fabrics after laundering treatments, while a decrease was caused after laundering of the polyester fabric. A decrease in tearing strength of all the fabrics was found after laundering with the treatments. The Anolyte also did not affect the dimensional stability of the fabrics. It could be concluded that the Anolyte is a viable alternative to currently used sodium hypochlorite, while it is effective at low temperatures. The Anolyte do not affect the textile fabrics more negatively than the detergent and sodium hypochlorite combination, and could, therefore, be a successful alternative.