Bleaching of Loom-Stat Cotton Fabric Using Activated Sodium Chlorite / Hexamethylenetetramine System

Abstract

Hexamethylenetetramine (HMTA) has been investigated as novel activator for sodium chlorite to effectively bleach loom state cotton fabric in one step process and in slightly alkaline medium. This was done with a view to avoiding the troubles associated with evaluation of chlorine dioxide during chlorite bleaching. Two techniques have been separately investigated to carry out the bleaching process, namely, exhaustion and pad steam technique. The process parameters in each technique have been investigated. Results obtained show that the addition of HMT A decreased the decomposition percent of sodium chlorite during the bleaching process. It has been also found that loom state cotton fabric can be bleached in one step process with NaClO 2 / HMT A using either exhaustion or pad-steam technique. In exhaustion system maximum W.I and wettability of bleached cotton fabric was obtained when loom state cotton fabric was bleached with an aqueous solution containing 3 g/l NaClO 2 and 0.08 g/l HMT A. Whereas, in pad steam technique, maximum W.I and wettability of bleached cotton fabric was obtained when loom state cotton fabric was bleached with an aqueous solution containing 20 g/l NaClO 2 and 0.6 g/l HMT A then steamed for 60 min.