Comparison of Various Additives in Cotton Bleaching Efficiency

Abstract

Bleaching efficiency is evaluated by the degree of whiteness, absorbency, copper number, tendering factor, strength or strength loss, dye uptake, alkali solubility, degree of polymerization and chemical transformation. Recent lab-scale studies have proven ozone to bleach with efficiency comparable to the conventional bleaching agents and hydrogen peroxide at faster rates without requiring heating or any other supportive treatment with less energy and water. Ozone alone, however, showed poor efficiency in pilot-scale determinations, suggesting the use of certain additives to support it in performing its bleaching action. This research was conducted to compare the influence of methanol, isopropanol, oxalic acid and sodium borohydride on improvement in the bleaching performance of ozone in terms of whiteness, absorbency and burst strength. The additives brought an overall improvement in whiteness, absorbency and burst strength of cotton but had significant difference in their performance, as assessed from the pvalues yielded by one-way ANOVA applied on SPSS 20. Methanol outclassed other three in its performance bringing the highest increase in whiteness and burst strength and the highest reduction in fabric absorbency.

The Effects of Ozone Bleaching and Ozone Desizing Method on Whiteness and Water Absorption of 100% Cotton Terry Fabrics

“…It was determined in this study that Ozone bleaching process containing additives provided a better whiteness degree and water absorbency than those obtained ozone alone process to cotton fabrics. [19] In a study, combination of ozone and ultrasound method was applied together to remove the sizing. This study shown that the results of desizing efficiency was nearly similar with those of conventional process [20].…”