The frictional behaviours of the thread wrapped around cylinder have been studied with a consideration on the flexual rigidity of thread. Firstly, assuming that the thread is a completely elastic body and the coefficient of friction between the thread and cylinder is constant, the studies were extended to general thread.
1). Basic Equation (Fig. 2)
where, T₀, T₁; thread tension acting at the contact end, F₀ F₁; reactive force acting at the contact end against cylinder, μ; coefficient of friction between thread and cylider, θ; contact angle of thread wrapping a round the cylinder.
2). General case (Fig. 3)
Using equation (a), the following is obtained.
where, t₀, t₁; thread tension acting at the thread end, ƒ₀, ƒ₁; normal force acting at the thread end, θ₀, θ₁; contact angle to the standard line, α₀, α₁; angle between thread at its end and perpendicular to the standard line.
3). When the thread is long enough (Fig. 5)
Using the relationships between the angles and equation (b) following formulas are obtained: The relationships between t₀ and t₁ are;
where, E; Young's modulus of the thread, I; moment of inertia of area of the thread, i.e. EI shows the flexual rigidity of thread, ρ; radius of cylinder.
the relationship between θ₀ and θ₁ is:
But, where the point contact or θ₀+θ₁=0, and
4). It has been found on the constant coefficient to friction as following:
i) The frictional force with rigidity is smaller on the thread than without (Fig. 8 and Fig. 9).
ii) The frictional behaviour may be approached to condition without rigidity as thread tension becomes greater (Fig. 8 and Fig. 9).
iii) The greater the coefficient of friction and turning angle are the more the frictions are influenced by flexual rigidity. And as these values are smaller these influences are trivial (Fig. 10).
iv) When the contact is at point, the ratio of final tension to initial tension is not changed by the tension of the thread as shown in equation (e).
v) When the contact is at point, its position does not change with the thread tension, as shown in equation (f.)
5). In general threads similar tendencies may be expected (Fig. 11).

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The thermal stability of the heated P. E. T. fiber has been discussed from the viewpoint of a fine structure, as reported in the previous paper ^{1), 2).} Dimensional stability of the thermo-plastic fiber is one of the most important properties for practical purpose and so the oriented P. E. T. fiber under various heated conditions was investigated to find out the temperature dependence of the thermal contraction in equilibrium. And in order to estimate a fine structure of fiber from the percentage of contrction, its value was quantified as a function of the degree of crystallization and orientation factor. The results obtained are ss follows:
1) The thermal equilibrium contraction curves are exhibeted with a characteristic sigmoid shape, which shows the percentage contraction increases with rising temperature. The temperature distribution curves of the thermal contraction in equilibrium have two peaks. Its maximum point in a low temperature range shifts towards higher temperature with increasing heatset temperature, while it may disappear at higher heated temperature beyond 170°C. And its distribution may become broader with heatset temperature. On the other hand, maximum position in a high temperature range is not affected by heated condition, but its value becomes larger with increased heatset temperature. The former may be due to a frozen strain occured on production production process, and the latter to the binding strain on drawing and afterheating processes.
2) Assuming that the thermal retraction of the fiber may becaused by deorient effect due to break-down of either crystallites or secondary bond among the oriented molecular chains in the amorphous region, then the temperature dependence on the thermal retraction in equilibrium may be represented by the following formula:
where: S₀: percentage contraction, when these bonds do not break down at all. S_T: percentage contraction at giving temperature (T°C) k: constant N_b: numbers of thesebonds among the oriented molcular chains in the amorphous region And considering the degree of crystallization (X) and orientation factor (ƒ), equation (1) may be transformed as follows:
And, curves obtained from the equation (2) agrees with experimental results. Consequently, intermolecular aggregation state may be estimated from thermal retraction behaviors.
3) Relation between the logarithmic of the thermal equilibrium contaction and the reciprocal of the reciprocal of the absolute temperature may be described by “Arrhenius Plot”. It comprises of three staight lines which have two transition temperatures. While the apparent activation energies obtained from slope of the straight lines decrease in a low temeperature range with increasing heatset temperature, their energies increase at a high temperature range.

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Relationships between the cross sections and the spinning conditions of the super high tenacity rayon were studied, From the results, it may be summerized as following:
(1) The circular form at the cross section is formed by the homogeneous coagulation and regeneration process.
(2) The skin layer of the cross sec_??_ion is formed in such a spinning condition that the rate of coagulation is larger than the rate of regeneration.

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The values of terminal velocity (in the case of natural falling) of the lints and trashes come off the surface of licker-in roller, are classified as follows:
1. The lints collected in the gap between licker-in roller and under-sheet after passing under mote-knife are less than 0.62m/sec, and many of those lints consistal of few fibres are generally about 0.38m/sec or less.
2. The trashes and motes dropped under licker-in roller are more than 1.44m/sec except for some of pepper.
3) The wastes dropped including immature fiber or bulky weighty are between 1.44m/sec and 0.62/sec.
Some of the lints and trashes are caught on the saw tooth wire of licker-in roller, moving in the direction of the cusp by centrifugal force relative to holding force, and are separated from the surface of licker-in roller by the edge of mote-knife. The particles separated from licker-in roller in the above mentioned step and the peppers separated directly before reaching the edge of mote-knife, are conveyed or dropped off by the pneumatical action of centrifugal air current and gravity force outside of currents.
The particles conveyed by currents along the back surface of mote-knife are classified by the inertia force resisting the curved currents along the arc surface of mote-knife, and the particles which have the values of terminal velocity more than 0.62m/sec move on straight to the bottom of space. The particles which have the values of terminal velocity less than 0.62m/sec move curving and contacting with the arc surface, and after separating from the arc surface they move for the gap between licker-in roller and under-sheet. And some of those bulky light particles which moved on the curved currents without touching the arc surface in the ranges of upward currents at the back side bacing the under-sheet, and ascend by buoyancy force.

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The previous paper (Part I) was reported on the yellowing of tyrosine, tryptphane and their mixed solution exposed to light within the range of 20_??_80 hrs.
In the present paper, an attempt is made to study on the yelowing of each solution mentioned obove, by exposing to light for various time of 0_??_20 hri., and the following results are obtained.
By comparison with the spectral optical density of each solution, it is found that the coloring processes of the mixed solution by light may be classified into the fallowing three periods;
In the first period (0_??_5hrs.), the coloring of tryptphane are scarcely recognized under the influence of tyrosine.
In the second period (5_??_10hrs.), the sensitization with respect to the visible light absorption appears rapidly at the short wave side.
In the third period (10_??_20hrs.), it proceeds slowly at the long wave side.
Considering the above facts from the colorimetrical point of view, the dominant wavelength of the mixed solution shifts from 573.0 to 575.5mμ.
The coloring phenomena of the silk stuffs are similar with the mixed solution: both the dominant wavelengths are between those of tyrosine and tryptphane.
In regard to the relation between transmittance T(%) of the mixed solution and exposure time t(hr), the following formulae, which bear the same relation to the case of that by exposing for a longer time, are obtained.
Where the values of k; depending on the wavelength, vary 3 to 4.

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The shrinkage of handknit yarn was studied by using shaking type felting machine. Regarding the effect of yarn twist, it was observed that higher twist, singles as well as ply, resulted lower shrinkage value and contribution of ply yarn twist to shrinkage was nearly constant in spite of variation in single yarn twist.
Tensile tests made with handknit yarns felted at various stages give the different typs of break.
When it's shrinkage is felted to 20-30% in length, the handknit yarn breaks sharply at places, and stepwise series of higher breaking extensions occur at others. This may be due to the entanglement of the constituent fibres.
In the course of felting, untwisting is observed up to 20-30% shrinkage, but not above that.
From these observations, it is supposed that up 20-30% shrinkage, untwisting played, main part in the felting of handknit yarn, but above that the entanglement of the fibres could be the main cause.

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The fading rate of Zambesi Black D (I) (C. I. Drect Black 17 C. I. 27700) and Aniline→p-cresidine→r-acid (II) for cellophane films was measured and CF curves of these dyes were determined by the Giless method. (I) contains two groups at the ends of conjugated chain which probably favours the bond formation. (II) contains only one group at one end.
The following observations are reported: There is no linear relationship between the logarithm optical density and irradiated time of these dyes on cellophane films i. e. the rate should not decrease exponentially with time. But when the 1/optical density is used for the vertical axis, the curve makes a straight line. These dyes are faded according to the second-order law in appearence. The fading reaction of (I) and (II) must therefore occurs in the same form.
Giles found that the intercepts of the CF curves on the y-axis for azoic dye rise with increase in the average particle size as judged visually under a microscope (Baxter, Giles. Miss Mc Kee and Macaulay, J. Soc. Dyer Col., 71, 218 (1955)).
These dyes in cellophane films have a positive slope. The intercepts of the CF curves on the y-axis for (II) rise more than (I). It may be supposed that (II) is in some form of more increased aggregated state than (I).

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Isotherms were measured for the distribution of dioxyethylaminoazobenzene (as a model of disperse dye) between water and benzene in the presence and absence of urea or sodium chloride at 10°, 20° and 30°C. From the results the thermodynamic parameters were calculated for the following process which consists of the transfer of one mole of the dye from a water environment to a benzene one.
Dye in water (mole fraction X_w)→dye in benzene (mole fraction X_B) (A)
The changes in the enthalpy and in the unitary free energy and entropy were zero, -3280 cal. (20°C) and +11 e. u.. respectively. It is seen that the process is nearly athermal and accompanied by a considerably large increase in the entropy. It is therefore clear that the affinity of the dye for benzene (negative unitary free energy change for the process (A)) is not caused by an energetic situation. It is associated entirely with a positive unitary entropy change.
The positive unitary entropy change for the process (A) strongly indicates the formation of so called “iceberg” water structure in the vicinity of the dye molecule in a water environment. The concept of “iceberg formation” can offer account for the origin of the positive unitary entropy change. When the dye leaves a water environment and enters a benzene one, the “iceberg” around the dye molecule will melt. For this “melt” of “iceberg” again in entropy may be expected.
The approximate number of water molecules in the “iceberg” around the dye estimated from the thermodynamic parameters was 20.
The thermodynamic parameters for the process (B) were culculated also.
Dye in water (mole fraction X_W)→dye in urea or sodium chloride solution (mole fraction X_S01) (B)
The unitary free energy change in the transfer of the dye from a pnre water to the 5 mole urea aqueous solution was -840 cal. The negative unitary free energy change indicates that the urea acts to stabilize the dye molecule in an aqueous environment It has been said that the urea breaks the “iceberg”, perhaps by some favourable interaction with the “iceberg” regions or by formation of structures similar to urea-hydrocarbon clathrates. According to this hypothesis the transfer of the dye molecule to the urea solution may be caused by an entropic situation.
The unitary free energy change corresponding to the transfer of the dye to the 1 mole sodium chloride aqueous solution was +480 cal. The positive unitary free energy change indicates that the salt acts to unstabilize the dye molecule in an aqueous environment. Kauzmann's assumption that the salt has an effect in promoting the “iceberg formation” can be used to account for this result. The low affinity of the dye for the salt solution may be caused by a large entropy loss resulting from an increase in the extent of the “iceberg” around the dye molecule in the salt solution.
From the results of this study it is reasonable to assume the “iceberg formation” in the vicinity of disperse dyes in a water environment, and there is a possibility that the “hydrophobic bond” may play some imprortant role in the interaction between disperse dyes and hydrophobic fibre.

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To investigate the most suitable solvent for the wool degreasing process of continuous method, the author has made some experimental measurements. This article describes the results of the fundamental experiments with 14 kinds of solvent and anhydrous lanolin.
The author concludes in this article that:
(1) The relation between treating time and quantity of dissolved anhydrous lanolin varies considerably with the kind of solvent used.
(2) The direction of dissolution of anhydrous lanolin varies with the specific gravity of the solvent.
(3) The solubility varies extremely with the kind of solvent used, and the minimum value of solubility is less than 1/100th of the maximum value of solubility.

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