Surface Wettability Scanning of Long Filaments by a Liquid Membrane Method

A technique is presented for characterizing the surface wettability of relatively long filaments based on scanning the filament with a liquid membrane. This technique overcomes the limitations of specimen size and crimp, which are inherent in the bulk immersion method for evaluating wettability changes along a filament. The technique can be used to study the surface distribution of finishes on long filaments, provided the wettability characteristics of the finished surface are significantly different from those of the untreated filament under the conditions of measurement. If the method is to be used to study finish distribution, an appropriate liquid must be used for the membrane, and guidelines for selection of such a liquid are discussed.