The detergency of surfactant mixtures and bentonites on cotton fabric

Abstract

The primary aim of this work is to attain improvement of the softness of cotton fabric during the washing process with ecological surfactants. To attain that improvement, sodium bentonite was added to the detergent formulations to produce a softening effect during washing and obtain the so called “soft detergent” effect. Sodium bentonite (a mineral composed mainly of hydrated aluminium silicates) was mixed with the surfactants used in ecological detergents. This product was used with a suitable particle size that, given its large specific surface area, facilitated its deposition on the cotton fabric, producing the desired effect of increasing the softness of the washed fabric. The surfactants used were an anionic surfactant, namely LAS, and two non-ionic surfactants, namely APG and AE, used separately and as mixtures, without co-formulants, to demonstrate their detersive power in one wash and repeated washes, depending on the nature of the surfactants and on their separate mixtures an mixtures in different proportions of anionic and non-ionic surfactants in combination in all cases with a constant concentration of sodium bentonite with two particle sizes. Evaluation was performed of the subjective softness (to the touch) of pairs of samples by several observers and also of changes in whiteness after deposition of the bentonite during washing