Redeposition of impurities on wool fabric during washing with ecological surfactants and solvent microemulsion

Abstract

In this work, redeposition performance during washing was studied after washing a wool fabric with addition of a solid impurity. The aim of this paper is to study addition of a non-toxic solvent mircoemulsion to conventional wash formulations with the aim of improving the performance of conventional washing. The non-toxic solvent used was dimethly sulfoxide micro-dispersed with an amphoteric surfactant as emulsifier. The fabric was washed with SDBS and biodegradable non-ionic surfactants such as an alcohol ethoxylate (AE) with 7 m.OE and an alkyl polyglucoside with 1.4 glucoside groups (APG). The fabric used was EMPA 217 wool fabric. The anionic and non-ionic surfactants and mixtures of the non ionic surfactants were used separately and in mixtures in varying proportions for the washes. Carbon black impurity was used as solid impurity for the washing. Sodium carbonate and sodium chloride were used as builders. The fabric was washed at low temperature (30º) with water of different hardness (20ºhf, 30ºhf,and 40ºhf). In all the cases performance was enhanced, i.e. redeposition of the carbon black solid impurity was decreased, for all the mixtures tested using the DMS mircoemulsion in the washing formulation.