This research studied moisture transport in a diverse group of knit fabrics. Fabric thickness, bulk density and air permeability are shown to be major determinants of moisture vapor transfer in these knit structures. Measures of steady state moisture vapor transmission, such as covered dish or guarded sweating hot plate methods, are strongly correlated with fabric thickness. Measures of microclimate humidity are sensitive to fabric air permeability. These findings are attributed to fundamental differences in steady state and equilibrium test methods and to mechanisms of moisture vapor transfer in open knit structures. Fiber cross-section, fineness, and type affect moisture vapor transmission as these variables affect the thickness and porosity of the knit fabric structure.; Liquid moisture transport is examined in light of the effect of fiber and fabric variables on the absorption capacity, absorption rate, and drying in knit materials. Absorption capacity is shown to correlate with fabric thickness, a primary determinant of pore volume available for liquid moisture retention. With the notable exception of slower dry wool knits, drying rates are essentially the same for all knit materials examined. Drying time is shown to be a direct function of absorption capacity. Wickability and absorption rate are discussed as complex functions of surface energy and fabric pore size. In wettable fabrics, fiber and fabric variables that produce structures having larger and unobstructed inter-fiber and inter-yarn capillaries contribute to increase absorption rate in knits. Differences in knit fabric absorption and wicking characteristics measured using vertical wicking, water drop and demand wettability tests are discussed in light of the mechanisms of measurement employed by each of these methods.
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