Ends-breakage are assumed to occur in the fiber bundle which forms a triangle zone between a front roller nip line and a twisting point.
On this assumption a theoretical investigation into end-breakage produced during spinning has been made together with such factors as tension, yarn irregularity, number of fibers and fiber strength.
The following equation for calculating absolute values of end-breakage rates during spinning has been derived :
Q=∫^Tmax_Tmin ∑^∞_n=0[∑ⁿ_m=0{_nc_mp^n-mq^mλn∫^∞₀g(x)dx}]k(T)d_T
where Q is the end-breakage rate for a predetermined spun length ;mis the number of fibers which are caught simultaneously between the front rollers and the twisting point ;nis the cross sectional number of fibers ; λn is the probability that fibersnare caught between the front rollers ;Tis the tension exerting on the triangle zone, k(T) is the probability density function ofT; p=I-q, q is the probability that a fiber is caught simultaneously between the front rollers and the twisting point ; and g (x) is the probability density function of X in which X=T-S-R where S is the strength of the fiber bundle in the trianglezone and R is a mutual resistance agaisnt slippage.
Since the values calculated by the equation lie substantially within the scope of the empiricallyknown end-breakage, it has been proved that the equation can be of practical use.

View full abstract

In previous article, for solving the problems of handling, a system which incorporates a method to measure handling was trially built up.
In this article, how to measure the handling of fabrics is discussed in detail.
1. The basic mechanical properties which seem to be representative of the mechanical properties of fabrics are shown in Table 1. The measuring method is summarized in Table 2.
2. An equation relating the basic mechanical properties to handling is derived on the basis of Weber's law :
Yi=2.30/αi log₁₀ Xi/Xsi
where Yi is the sensibility of handling corresponding to the basic mechanical properties Ai, Xi is the measured value of Ai, α is the sensory differential limen, and Xsi is the standard value of Ai.
3. The differential limens and standard values of the basic mechanical properrities are presented in numerals.
4. The numerical and graphical methods for expressing the results of measurements are discussed.An example of the applications of this method to the practical use is given.

View full abstract

The previous paper dealt with, the fundamental behaviors of nylon 6 fibers subjected to thermal treatment in super heated steam under atmospheric pressure, which were compared with those in dry heat.
The present paper relates to the effect of heat treatment in the steam on a running yarn (non-twisted, and false twisted yarn) in comparison with that in dry heat.
1) The thermal effect on the density for the non-twisted nylon 6 yarn shows exactly the same tendency (i.e., minimum point at about 150°C) as in the previous paper. In the false twisted yarn, the density gradually increases as temperature rises.
2) The surface filaments of the false twisted yarn are affected by the relative humidity in the treatment chamber. The inner filaments are influenced by the moisture which the filaments absorbed before the treatment.
3) The crimp of the yarn texturized with the steam is superior in character to that of the yarn in dry heat.

View full abstract