| Abstract: | ![]()
This study is concerned with the physico-chemical background to the substitution of phosphates in laundry detergents, with special emphasis on combinations of zeolite A with other detergent ingredients, especially water-soluble cobuilders and optical brighteners. The most important action mechanisms of zeolite A / cobuilder systems were investigated for a variety of washing conditions. It is shown that the builder performance of zeolite A is often reinforced by small amounts of water-soluble substances such as polycarboxylates. These detergents are able to compete, in terms of performance, with products containing a high proportion of phosphate. Further, the interaction of zeolite A with fluorescent whitening agents in detergent powders was studied. It is shown that the photophysical properties of a typical optical brightener are negatively influenced by ionic builders and surfactants. In contrast to sodium triphosphate, zeolite A can enhance the appearance of powders even in the presence of anionic surfactants.Lecture presented at the International Symposium on Zeolites, Zeolites as Catalysts, Sorbents and Detergent Builders, Würzburg, September 4–8, 1988. |
