This paper outlines the operating method to measure the bending length of comparatively stiff fabrics by the Clark method which has been widely used in commercial routine test and standardized as the Japanese Industrial Standard (JIS), and presented the theoretical basis of this method.
The Clark method is a modified method of heavy cantilever method developed by F. T. Peirce. In the case of the Clark method, the test piece is clamped at any angle with horizontal base, and when the angle reaches a critical value, a deflected state shifts to another stable state. The critical angle at which snapthrough occurs is a function of bending length and hanging length of the test specimen. We have derived this relation theoretically on the assumption that the test specimen is completely elastic. According to the theoretical calculation, the length corresponding to a critical angle 45°whose length has been used as a measure of fabric stiffness is about 2.84 times of bending length. This relation is experimentally verified by many kinds of woven fabrics and papers, and it is concluded that this theory is applicable to the measurement of the bending length by using the Clark Stiffness Tester. The values obtained from this method correlate well to the values from 41.5° cantilever method. But the values from the Clark method is smaller by approximately 10% than the values from the latter methods.

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In the previous paper, relation between making-up properties and physical properties of men's suit fabrics have been analysed and it has been revealed that fabrics having heavier weight perunit area give good appearance for men's suits in finished garments.
In this paper, a method is proposed to predict the making-up properties of fabrics for men's summer suits having regular patterns. The method was also investigated to predict the making-up properties of fabrics for summer suits of inferior sewability and worse making-up than those for winter suits. Furthermore not only reliability of the predicting equation was introduced but also physical properties of fabrics which give good making-up for suits were discussed in detail.
The evaluation of making-up has been made by experts of clothing manufacturers. Physical properties of those fabrics, i. e., tensile, bending, compressive, surface properties and thickness, weight were measured by KES-F fabric testing system.
The results are summarized as follows :
1) Three basic properties of fabrics, i.e., bending, tensile and shearing properties remarkably contribute to making-up properties of summer suits. Ranges and characteristics of these values for fabrics which give better making-up were clarified.
2) Among the physical properties, bending property in weft direction shows the largest contribution to making-up and tensile property in the same direction shows larger one. These properties relate to formability and shape retention of suits.
3) The equation which predicts making-up properties could be derived from combination of the three basic physical properties, bending, tensile and shearing properties. The predicting equation is rather simple but highly reliable.

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In general, ring spinning and winding processes areseparately operated in the textile industry. Therefore, even if one has succeeded in an unattended operation in these two processes for saving labour cost, there would still remain many troubles in their operation, maintenance and system reliability because of their complicatedmechanism, and also such unattended system would be usually more expensive than conventional spinning processes.
We have succeeded in combining ring frame andwinding machine to develope the improved system. Thisnew spinning system called “PAS System” is able to produce cheeses or cones from slivers or rovings directly.
The PAS System is quite simple and applicable toother spinning processes. Comparing the PAS Systemwith open end spinning systems, the PAS System hassome advantages in production cost. We believe thatthe PAS System could provide an advanced step in thespinning-winding processes.

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The mechanism of backtanning of nylon 6 fibers has been studied by X - ray diffraction, dynamic mechanical properties and rate of dyeing. The following results were obtained.
(1) The (200) lattice spacing and crystallite size increased by backtanning treatment, but the (002) lattice spacing decreased.
(2) The temperature of the peak of tanσ of nylon 6 fibers treated with backtanning was higher than that of the untreated fibers.
(3) The rate of dyeing of disperse dyes into the nylon 6 fibers treated with backtanning was lower than that of the untreated fibers.

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