To examine the aesthetic properties of pantyhose, an image analysis and wear experiment were carried out. We analyzed both the area ratio of light, medium, and dark lightness areas and the position of three areas in the distribution of lightness difference between legs with and without pantyhose fabric. The data was used to determine what effect these two variables have on the visual appeal of legs in pantyhose. Moreover, we examined the relationship between pantyhose size and women’s leg size on the attractiveness of legs in pantyhose made from single covered yarn with colored polyurethane core yarn. The results showed that, for the enhanced visual appeal of legs in pantyhose, (1) the area ratio and position of three areas in the distribution of lightness difference were very important factors; (2) it was desirable to design and produce the appropriate size of pantyhose for various sized legs in order to enhance their attractiveness.

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We experimentally discussed the effects of airflow geometries in an air suction gun on the suction characteristics of running yarn. Geometry parameters focused on were 1) compressed-air inflow angle of nozzle, 2) diverging angle of nozzle, 3) throat diameter of de Laval tube, 4) converging angle of de Laval tube and 5) yarn propulsion tube length. As a result, effects of the geometry parameters on the yarn suction force, the mass flow rate of compressed-air and the yarn suction efficiency, which is defined as the yarn suction force divided by the mass flow rate of compressed-air, were made clear and the optimum geometry of an air suction gun was obtained on the basis of the energy efficiency. In addition, the yarn suction force showed two types of time dependency because of different yarn motion on some experimental conditions.

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The objective of the present work is to well understand the mechanism of fiber assembly orientation in various flows involving the processing of composite materials. The evolution of the orientation of fiber assembly in a Newtonian flow through a 4:1 abrupt contraction has been numerically simulated by decoupling flow kinematics with fiber orientation which can be described using the Jeffery equation. It became apparent that (1) two types of abrupt changes in the director angle of fiber assembly were confirmed: the director angle continuously changes through 0° (oscillation phenomenon) and it reaches ±90° (flip-over); (2) fiber assembly completely aligns to the streamline (co-linear alignment) in the contraction for large aspect-ratio fibers and the co-linear alignment can be also observed near the channel wall in the upstream region. Furthermore, the predicted results for fiber orientation qualitatively agreed with the observed phenomena revealed from our previous work.

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Water transporting properties of waterproof/moisture-permeable nylon fabrics were studied by analyzing the structure of cross-section of fabrics. Samples of nylon fabrics were prepared by two-steps of processing, i.e., casting of the polyester-type polyurethane by wet-coagulation process and the after-treatment of hydrophilic/hydrophobic agents on the surface of polyurethane layer which exists in the inner side of clothes when wearing.
 The fabrics consist of three layers: (1) Inner surface which comes into contact with wearer’s skin has micro-networks formed by using hydrophilic soil release agents or hydrophobic water repellent agents. (2) Intermediate porous layer is the polyurethane one useful for moisture transportation. (3) Outer surface is composed of hydrophobic nylon fabric combined with water repellent treatment.
 The results obtained from the research are as follows: Dew condensation and water-vapor resistance, which have a correlation with water transporting properties, decreased with forming hydrophobic micro-networks on the inner surface. This fact suggests possibility of developing more comfortable fabrics suitable for sports-wear, etc.. Furthermore, dew condensation had a relation with water-vapor resistance in the water transport evaluation.

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