Studies of Detergency. XIII.

Abstract

The soil removal efficiencies have been studied from the view of hydrophilic or oleophilic nature of surfactants, soil, and fabrics.In the case of washing by the detergent that is mainly formulated with LAS, the detergency depends on water hardness. The water hardness dependencies on the detergency for the hydrophilic fabrics such as cotton and nylon are comparatively small, but are great for the oleophilic fabrics such as wool, and consequently the maximum detergency is observed at a some water hardness.The water hardnesses corresponding to the maximum detergency depend on the polarity of soils adhered on fabric and increase with the increase of the polarity of soil.In the case of washing by the detergents that are mainly formulated with non-ionic surfactants, the dependency of detergency on the HLB of the surfactants is little for the hydrophilic fabrics such as cotton, but is great for the oleophilic fabrics such as wool.