The tactile evaluation was performed on 16 cotton towel samples that had been washed different numbers of times. Twenty-seven female and 24 male university students (20–24 years old) participated in the assessment. The surface and compression properties of fabrics were measured with the KES system. The tactile feels of softness and of smoothness were related to the geometrical roughness (SMD) and compression linearity (LC). The tactile feel was worse for washed towels with higher SMD and LC values. For washed towel fabrics, we found no significant correlation between the tactile feel and compression energy (WC). The results were related to the changes that occurred in the pile loop geometry during washing and caused matting of the pile. The changes were characterized by the ratio of ground fabric area observed in microscope images. To evaluate the initial resistance of the matted pile, we measured the frictional force (Ff) during movement of a friction contactor on the pile. The slope of the Ff peak (S-FfP) was a useful indicator for investigating the tactile change in towel fabrics after washing.

In conventional tensile tests for textile materials, a pretension is applied to the specimens to obtain a credible sample length. However, when we wear a comfortable garment, many yarns in it are not stretched. So, we consider that the transition behavior of textile materials from relaxed to low-stress conditions is important in evaluating the comfort of a garment. As a preliminary study, we developed an analytical method for tensile-test results of slacked yarn, where we applied the Savitzky-Golay approach to compute the second derivative-graphs of the original curves and fitted them with two beta distribution probability density functions using the least-squares method. In the experiment, we measured the tensile-test curves of an untwisted polyester multifilament yarn with intentional slack. Our results show that the second-derivative graph is well summarized by our model using the least-squares method. As well, the overall load-extension properties, including slack length of each specimen, also can be analyzed objectively in our method.