Production of light weight high quality worsted fabric needs fine count single warp yarn. Single worsted yarns are highly extensible and have too much hairiness to be woven as warp. Sizing is essential to make these yarns weavable. Conventional sizing is not suitable for woolen/worsted warps because of their stretchability and heat sensitivity. Cold sizing is found to be one of the alternatives to solve this problem. However, selection of appropriate size composition and application technique are key parameters for successful weaving of these yarns.

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The elastic constants are approximately determined using a multi-step linear approximation method for more accurate material nonlinear analysis of coated fabric membrane structures. The approximate determination is performed within each quadrilateral or triangular surface defined on the surfaces of the biaxial elongation property formed with the data of stress-strain curves measured by biaxial extension testings. Two types of 40 × 40 cm square flat membrane model of a PTFE coated plain-weave glass fiber fabric are analyzed applying finite element method adapting a 20-steps linear approximation method. One of the models is an inplane deformation model subjected to biaxial extension under the condition of stress ratio of 1:1. The stress-strain response in the central region of the membrane is analyzed. And the other model is a membrane deformed by the application of air pressure. The relation between the central deflection and the pressure is analyzed. The results of analysis showed excellent coincidences with experimental results.

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The following are the results of an examination of the anti-static effects of the various combinations of tile-carpets and free-access floors, taking the influence of relative humidity into consideration, using JIS A 1455: Anti-static effect of floor coverings and installed floors - Methods of measurement and evaluation.
(1) Relative humidity affects electrification performance, which declines when using free-access floors with the electrostatic tester approved by the Architectural floor special performance society.
(2) The electrification performance of a floor declines when using free-access floors with the electrification between panels and bases between panels and bases eliminated beforehand, even if the same tile-carpets are used. As far as the measurement results at present are concerned, no difference occurs in electrification performance depending on the materials of free-access floors.
(3) Some carpets show different evaluations, when measured by the electrostatic tester of the Architectural floor special performance society, even where there is no difference in the evaluations of electrification using the Strolling method. When using the strolling method, some floor coverings which apparently have lower anti-static quality show lower static electrification performance than those which are vested with anti-static quality.
(4) Carpets which are more receptive to static electricity due to their lower surface and volume resistances tend to have higher electrification performance.

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This study aims to obtain some guidelines for designing high elastic knee-socks that will reduce muscle fatigue. Fourteen young women were employed as test subjects. Four samples of high elastic knee-socks with differing tensile property were used. We examined the relation between clothing pressure and the results of an electromyogram (EMG) of subject's legs when walking.
The results showed that the socks were effective when the clothing pressure at Tibialis Anterior (TA) was about 1.7 kPa, Gastrocnemius Lateral Head (GLH) at about 1.5kPa, and Gastrocnemius Medial Head (GMH) at about 1.1 kPa. At the Soleus, the socks with less elongation in the warp direction were effective.

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Laser Induced Fluorescence (LIF) method is one of the fluorescence analysis methods that are very excellent methods as one of the quantitative analysis of the material of a small amount. This paper describes a new evaluation method of adhesion soil in woven fabrics by using LIF Spectroscopy. LIF spectra were measured by a developed measuring system. There are a peculiar absorption peak and luminescence peak in the molecule. In this research, we used artificial sweat and artificial lipid as model soil of sample. Then we used cotton cloth, cupro cloth, rayon cloth as standard cloth of sample. Fluorescence intensity of each sample was measured, and the quantitative evaluation of the model soil was done based on fluorescence intensity. This paper also describes the grasp of the distribution situation of the model soil in two dimensions.

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Various kinds of airflow are used for operating yarn during textile processes. In this study, we calculated numerically compressible airflows past a yarn in a thin pipe in order to operate yarn using both a circular jet and an annular jet. We proposed the way to arrange air drag coefficients of yarns by Reynolds numbers adopted the yarn length exposed to the airflow as the representative length for the higher range of pressured airflows taking their compressibility into consideration. Simulated results elucidated both the air velocity and density profiles in a thin pipe for both jets. In the circular jet, the influence of the potential core was strong but it disappeared comparatively earlier. At higher supplying pressure, the compressed air was not able to fully accelerate in the pipe because it kept high density and took under-expansion. On the other hand, in the annular jet, the influence of the potential core was small, thus the compressed air fully accelerated and expanded in the pipe even at higher supplying pressure. Furthermore, yarn operation experiments showed that increasing supplying pressure was not effective to accelerate yarn running speed, and yarn troubles such as yarn twist or entanglement occurred at supplying pressure higher than 0.3MPa for both jets.

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