Abstract
The aim of this paper was to study addition of a non-toxic solvent microemulsion to conventional wash formulations with the aim of improving the performance of the conventional washing. In this work, the redeposition performance during washing was studied after washing a wool fabric with addition of a solid impurity The non-toxic solvent used was dimethyl 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. EO 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 mixture in varying proportions for the washes. Carbon black was used as the solid impurity in the washing. Sodium carbonate and sodium chloride were used as builders. The fabric was washed at low temperature (30° C) with water of different hardness. In all the cases, the performance in terms of redeposition of the solid impurity (carbon black) was enhanced (decreased) for all the mixtures tested when using the microemulsion of DMS in the washing formulation.