Abstract
The effects of anionic surfactants on wool shrinkage were investigated.
Wool shrinkage was largest when wool was in sodium salt solution of saturated primary alcohol sulfates at a certain concentration of detergents, in which the concentration was lower than the critical micelle concentration obtained from surface tension. In sodium salt solution of oleyl alcohol sulfate, however, such a phenomenon was not observed, and wool shrinkage became more or less constant when solution concentration was 0.1% and over.
Wool shrinkage was smaller when wool was in 0.1% solution of sodium salt of alkyl benzene sulfonate than that in water alone.
In the solution of sodium salt of laurate, wool shrinkage was maximum at a concentration around its critical micelle concentration. But in case sodium salt of oleate, no such concentration maximizing the wool shrinkage was observed.
Excluding the effect of viscosity, commercial soaps showed nearly a fixed value for wool shrinkage when its concentration was higher than 0.3%.
