Application of stochastic simulation to a uniaxial elongation flow and fiber spinning of polymer melts were investigated. In the numerical simulation of fiber spinning, a one dimensional approximation was employed. The stochastic simulation was performed based on the stochastic differential equation equivalent to the diffusion equation of a probability density for the Doi-Edwards and the Curtiss-Bird models. The stress field was computed from the results of the stochastic simulation. The computation of velocity field was decoupled with that of the stochastic simulation. It was confirmed that the elongation viscosity predicted by the stochastic simulation coincided with that predicted with the differential-approximated Doi-Edwards model. Furthermore, stress growth and temporal change in orientation vectors were successfully predicted. The numerical simulation indicated that the present approach was applicable to the fiber spinning problems and gave useful information relating fluid microstructures such as polymer orientation.

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Thickness changes in model futons contains two kinds of recycled fiber assemblies made from knitted sweaters fabrics were evaluated by the repeated compression test. Initial thickness under a constant weight for the recycled fiber assemblies was smaller than for pure wool and wool-blended samples. There were less reduction in thickness of the model futons filled with recycled fiber assemblies compared with the model futons filled with wool fiber assemblies during the repeated compression test. The yarns remained in the recycled fiber mass contributed to the less reduction in thickness of model futons. For the wool blend recycled sample, the compression rigidity was small compared with that of unused wool and wool-blended fiber assemblies, because recycled fiber assemblies made from sweaters consist of relatively fine wool fibers. The recycled sample showed less reduction in thickness of model futons and expected to be soft during use. It was confirmed that this material was suitable for the filling of futons and cushions.

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This study examines the feasibility of co-electrospinning vapor grown carbon nanofibers (VGNF) within thermoplastic elastomer. The reinforcement effect was studied. The diameter of the thermoplastic elastomer was found to range from 0.5 to 3 μm. The mechanical properties of the electrospun fibrous structure were found to be similar to that of cast elastomeric films. However, the electrospun fibrous membranes have superior tactile properties. The addition of VGNF significantly increases the bulkiness of the fibrous elastomeric membranes.

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This study aims to obtain the geometrical conditions of pattern elements of sine wave group patterns needed to give the observer a feeling of the waviness created by the patterns and fundamental guidelines for designing skirts with such patterns. The authors examined the effects of the period, amplitude, phase and grouping of the patterns on the wave feeling using paper skirts with the patterns printed and worn by a whole body mannequin. Female university students evaluated the wave feeling of the patterns using the semantic differential method. The geometrical conditions of different kinds of patterns for skirts were clarified numerically.

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In this paper, the helix number of hard twisted yarn was analyzed by both theory and experiment. The shape of hard twisted yarn was supposed as the helix and the helix number was examined from the dynamic balance of moment.
The results obtained are as follows:
1) Bending rigidity and twisting moment are strongly concerned in the deformation of hard twisted yarn.
2) The smaller the bending rigidity of hard twisted yarns, the larger the helix numbers of hard twisted yarn.
3) By increasing the twisted moment, the helix number of hard twisted yarns increases.

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