Recent advances in detergency theory

Practical detersive systems are inherently complicated, involving multiphase multicomponent soils adherent to a substrate, immersed in a multicomponent bath. Detergency is therefore not a simple colloidal effect, but the result of a large number of colloidal effects occurring simultaneously, each at its characteristic rate. To consider such systems meaningfully they are first resolved into a series of simpler model systems, each of which can usually be arranged to consist of three homogenous phases. Cleaning is the net result of the transitions of these model systems between the agglomerated (adherent) and the dispersed (separated) states. These transitions can be described and predicted in terms of well established, generally accepted concepts of modern colloid science. The resolution of typical detersive systems into their simple constituent models and the mechanisms of soil separation in these models are illustrated and discussed.