Moisture sorption properties and their relation both to noncrystallinity and to crystallite size were investigated for as-polymerized poly (p-phenylene terephthalamide) (PPTA) paricles. Degree of crystallinity in the PPTA particles after heat-treatment estimated from a wide-angle X-ray diffraction measurements was at most 64%, which was lower than that in regular Kevlar. Crystallite size for the PPTA particles was also smaller than that for regular Kevlar. However, crystal lattice struture was almost the same between the particle specimens and Kevlar fibers. The plot of moisture regain vs. heat of wetting showed linear relation, indicating nearly the same magnitude of interaction of water to the amide groups both for the PPTA particles and for Kevlar fibers.The ralation between the heat of wetting (or moisture regain) and degree of noncrystallinity linearly changed among the four kinds of fibers. However, the heat of wetting (or moisture regain) for the PPTA particles showed higher values than estimated from the linear relation in the plot obtained for the fibers. This suggested the difference in the three dimensional noncrystalline stucture between PPTA particles and fibers. Higher amount of free amide groups and easier accessibility of water to the amide groups due to the random orientation of the molecular chains enabled the higher moisture sorption in the as-polymerized PPTA particles.

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In the previous paper, the opening mechanisms of bale opener was investigated by using mass balance analyses, tooth edge locus analysis and two bale model experiments. Some primary factors about how to open fine and uniform tufts were derived. The condition that plucking ratio (Rp) value is high and constant seems to be very important to make good quality yarn finally. Therefore in this paper, the relationships between Rp value, and 1) bale surface condition and opening condition, 2) length and direction of the fiber which composes bale are discussed through experimental study by using real bales.
The results can be summarized as follows :
1. Tuft weight Wp and Rp increases proportionally as the bale feed speed increases.
2. In the case that the bale feed speed is constant, both Wp and Rp increases once and then decreases as the parallel press bars force onto bale surface increases. In these relationships, the condition to realize the low Wp with the high Rp can not be found.
3. As for the effects of the fiber length of bale, tuft weight becomes smaller at shorter fiber length and Rp value are higher at both longer and shorter end sides of fiber length. As for the effects of fiber direction of bale, Wp becomes smaller and Rp value is higher when tufts is obliquely plucked.

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Seam pucker means a phenomenon which appears along the seam line when two perces of fabric are sewn together by a sewing machine. It was found that among fabric mechanical properties, weight, extensibility bending rigidety, thickness and surface friction coefficient have relation to seam pucker. But it was difficult predict grade of seam pucker over all different types of fabric accurately by a multiple regression equation.However, it was found possible to predict commercial acceptability precisely of all fabric sewn under several sewing machine conditions, by discriminant analysis using only two variables. And this allows suggesting the proper sewing machine conditions for each fabric simply. Modification of textile mechanical properties and ironning were discussed for faric uncontrolled by adjusting sewing machine conditions. Futhermore seam pucker prediction in the designing stage was discussed.

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