Abstract
When fiber assemblies such as yarns and fabrics are washed, substances to be removed migrate through water and fibers. The coefficient of diffusion of the substance in water is remarkably different from that in fibers. In the previous papers[1, 2], treating the process of substance migration in fibers and water, an assumption was made that fibers can be regarded as columns and fiber assemblies as planes or columns. Theoretical equations had been derived on the basis of the diffusion theory and the validity of these equations had been confirmed by the washing experiment of polyvinylalcohol[10].
This paper deals with the washing of cotton and polyester fabrics, the properties of which are much different. Sodiumhydroxide and acidic dyestuff are selected as the substances to be removed. The experimental values are compared with the theoretical values. Results of washing in stirred water agree well with the values calculated by equations derived by regarding the fiber assembly as a column.
