Interaction between the Surface Properties of the Textiles and the Deposition of Cationic Softener

In this study we categorised the surface properties of different knitted fabrics by their electro-kinetic behaviour and liquid up-take phenomena of the knitted textiles in order to understand the interaction of the surface properties of the textiles with cationic softener deposition. The electro-kinetic and liquid uptake properties of textiles were measured by their zeta-potential and liquid absorption ability. We also examined the influence of fabric softener on the surface characteristics of the textiles. We used solvent extraction followed by cationic titration to determine the cationic softener level present on the textiles. The major finding of this study was the different behaviour of individual loads and mixed loads in terms of cationic pick up from the rinse cycle softener. Fibre type plays the most critical role in determining the zeta potential of the fibre, filtration efficiency and water retaining capability of the fabrics, which in turn play the most important role in softener deposition on the textile. The charge on the textile surface is negative; this plays a key role in the deposition of the cationic softener in both kinds of loading conditions. Capillary diffusion could be a key parameter only in the individual load condition. It was found that there is a significant reduction in the liquid adsorption weight when fabrics are treated with levels of softener that are much higher than those associated with normal consumer use. As soon as the fabric comes into contact with the liquid, the fabric softener molecules transfer from the fabric to the liquid and reduce the surface energy of the liquid. This results in an increase in the wetting weight of the fabric.