Sitting comfort of leather car seat, whose grain leather pattern were different, were evaluated by the sensory evaluation. Physical properties and body pressure distributions of leather car seat were also measured. The adjectives used for sensory evaluation were examined by principle component analysis. From the results of subjective measurements, samples with larger unevenness of the grain were evaluated as not high-quality, not relaxed and not comfortable. Samples with smaller unevenness of the grain and smooth were evaluated as simple, familiar and comfortable. From the use of principal component analysis, two principal components were obtained, therefore, the sitting comfort were evaluated by "high-class" and "familiar". From the correlations between sensory evaluations and physical properties or body pressure distributions, the sitting comfort of leather car seat have correlations with the physical properties, which are friction properties of surface, and with the contact pressure of the mannequin and the car seat. From the correlations of tactile sensations and sitting images adjectives, the sitting comfort for leather car seat could not be predicted by the tactile sensations of leather car seat covers. There were greatly difference between the evaluation of sitting comfort for the fabric car seat and those for the leather car seat.

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In order to design new socks for soccer sports that do not slip down easily, we performed impact tests by jumping down of a subject wearing socks, so as to analyze and understand the principals involved in sock slipping. We then developed a prototype impact testing device of sock slipping and performed several impact tests.
Impact sock slipping can be explained by a simple dynamical model of three forces generated by the collision between the sock-covered leg and the ground. The three forces are the inertial force acting on the sock, frictional force acting between the sock and leg, and impulsive force acting on the leg. In the prototype impact testing device, a conical leg model with a sock was allowed to fall freely. The collision between the leg model and the ground was used to evaluate and test the sock slipping. As a result, the impact testing device had excellent reproducibility, and its usefulness was confirmed. To prevent the discomfort due to the sock slipping and ensure the leg safety for soccer sports subjected to severe conditions, novel socks designs of soccer sports will be needed to control the material, stitch, clothing pressure, and coefficient of friction according to the end-use performance.

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