The Soiling Characteristics of Textile Fibers

Abstract
Methods are described for measuring the comparative soiling tendencies of textile fibers. It is shown that reflectance readings on soiled fibers measure an overall effect, part of which can be attributed to the weight and particle-size distribution of the retained soil, and part to the optical properties of the fibers themselves. It is suggested that the "effective soil content," which is defined as the weight of soil retained multiplied by the specific absorbance (of light) of that soil, is a more significant criterion of soiling than is either the weight of soil retained or the decrease in reflectance produced by the soil. Relative values for the effective soil content can be calculated from reflectance readings through use of the Kubelka-Munk equation. The soil retention of the fibers studied in creased in the following order: cotton, acetate, viscose rayon, nylon (variable, depending on soiling conditions), wool. The same order was maintained when the time of contact with the soil varied from 5 to 80 min. The soil retention of all the fibers increased with decreasing moisture content of the yarn. The presence of even small amounts of oily material in the yarn increased substantially the amount of soil retained.