Foam/Fabric Interaction Under Shear

Abstract

The increasing use of foams in textile wet processing has generated a need for better understanding of the factors that control such processes. Most studies until now have dealt with the influence of foam properties on the transport of chemicals into the fabric, but the chemical and physical properties of the fabric should also affect both material transport and foam stability. In all foam finishing processes, shear occurs at the foam/fabric interface, and it seems reasonable that the magnitude of that shear would reflect interfacial adhesion and be sensitive to the characteristics of both ma terials. A relatively simple method has been devised to quantify the interactions between foam and fabric by determining the shear stress that develops as a foam moves along a fabric. Reproducible shear stress values are obtained that depend on the blow ratio and bubble size distribution of the foam and also on the fabric properties thus far explored - aspects of both their chemical nature (fiber type, surface treatment) and their physical structure (surface roughness).