The effects of the various melt spinning conditions such as linear velocity in capillary, draft (or winding speed), cooling path distance and temperature of chilled bath on some properties of undrawn filaments were investigated.
The increase of linear velocity in capillary and draft produces the orientation of molecular chains which results in the indistinctness of yield point, the increase of tensile strength and the decrease of elongation of the stress-strain curves. The birefringence of undrawn filament also increases with the increase of above two spinning conditions. These orientations of molecular chains also increase by the increase of the shear rate owing to the decrease of capillary diameter and the increase of the melt viscosity due to the increase of Mn. The cooling conditions chiefly influence the crystallinity of undrawn filaments. Consequently, in our experimental conditions, it is observed that the densities of filaments become smaller by the sudden quenching.

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The filterability of the viscose prepared by the emulsion xanthation process was compared with that of the viscose prepared by conventional process. If emulsion xanthation is performed under suitable conditions concerning the amount of CS₂ and NaOH concentration, the filterabilities of the viscoses prepared by both processes are fairly correlative. In this case, most suitable conditionss of emulsion xanthation are as follows.
When sheet-formed pulp was used 12g (bone-dry) of air dried pulp which is remade into loose sheet in distilled water, 324 cc of 13% NaOH and two varying additions of CS₂ (90% and 170% basis pulp) were simultaneously shaken in stoppered glass bottle for 4 hrs. at 20C°. Sample was ripened over night at 20°C, and filtered through 5 sheets of carico under the pressure of 40 cm height of mercury, and clogging constant (KW) was calculated.
Furthermore, emulsion xanthation of alkali cellulose which were aged according to conventional process and so-called sulfidation-resistance according to Bartunek's method were also studied.

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Ultraviolet spectra of the phosphoric acid solutions of glucose, mannose, xylose and cellulose acetates and their fractions were determined, and the cause of the absorption by cellulose acetates and their fractions was investigated.
The ultraviolet absorption of the phosphoric acid solutions of cellulose acetates, especially that at 280-290mμ, is caused by saccharides produced by hydrolysis of cellulose acetates and by modified celluloses and their hydrolyzed products. Especially, xylose, which has strong absorption power and is easily produced from hemicelluloses, and modified celluloses, which have stronger absorption than pure cellulose, are main factors for the absorption. Therefore, unfractionated cellulose acetates, which include a large amount of hemicelluloses and modified celluloses, such as acetates from wood pulps generally exhibit stronger absorption. The first fractions of the acetates made of Rayaceta showed stronger absorption power that the intermediate fractions. may be less The last fraction showed an abnormal spectrum curve. Lignin content in the hazy first fraction than 0.1%, if present at all.

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The viscoelastie properties of Lincoln wool fiber supercontracted, in boiling water and those of non-supercentractad immersed in water and phenol solution were studied experimentally by means of free vibration type rheometer (period=10.64 second for free vibration) and extensometer of constant rate of traverse type.
The following results were obtained:
1) In water, the initial Young's modulus and viscosity of the wool, supercontracted in boiling water, decrease as compeard with the untreated wool.
2) The initial Young's modulus of the wool, immersed in phenol solution, decreases as compared with the one, immersed in water, those indicates the breaking of weak hydrogen bonds by phenol.
3) The hydrogen bonds are affected strongly at the initial modulus of load-elongation curve, of the wool, and these hydrogen bonds are bsoken easily by phenol solution of certain concentration at room temperature.
4) Both the Young's moduli and coefficients of viscosity at different points in the range of the 0-25 percent extension curve decrease in phenol solution, but relaxation times increase.

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The measurements have been made of frictional forces for viscose fibers (about 20μ in diameter) which crossed each other at right angle by means of stick-slip method. The following results were obtained:
(1) At applied loads 2mg to 30mg, the relation between frictional forces and applied loads is linear. (see Fig. 1. 2)
(2) At relative velocities 0.1cm/sec to 1.4cm/sec, frictional forces only depend on the applied loads and remain independent on relative velocities. (see Fig. 1. 3)
(3) When a fiber is pulled out perpendicular to a group of parallel fibres, each of them having a same tension, withdrawal frictional forces increase linear to numbers of its crossing fibers. (see Fig. 1. 4)
(4) Under a constant applied load, the distribution curve for frictional forces of inter-fiber, crossed each other, have the biased maximum at the lower range of frictional force. (see Fig. 1. 5)

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The effects of tension and twist to the dynamic moduli mainly, modulus of elasticity, coefficient of viscosity and energy loss, of crimped viscose spun rayon sliver (length 20cm, linear density 0.038g/cm) were investigated by means of the damped oscillating method of pendulum type under the low frequency of 0.5cps.
During the investigation, it was found that the amplitude of each sliver (maximum relatived deformation: 0.75%) damped exponentially as the oscillation decreases. Then dynamic properties of twisted sliver were evaluated by application of the theory of the visco-elastic models, and following results were obtained.
(1) In the case of fixed twist number of sliver, in the range of twist 0 to 6 turns per initial length of 20cm, modulus of elasticity, coefficient of viscosity and energy loss of each sliver increased respectively with increasing applied loads of sliver from 0 to 50g. (See Fig. 6, 7 & 8).
(2) In the case of fixed applied load, in the range of 0 to 60g, modulus of elasticity, coefficient of viscosity and energy loss of each sliver increased reqpectively with increasing twist numbers from 0 to 6 per initial length 20cm. (See Fig. 6, 7 & 8)
(3) Comparing the dynamic properties of loaded sliver twist previously with those of twisted sliver loaded previously it was found that, at the same number of twist per initial length, the values of period and logarithmic decrement of the latter were equal to those values of the former, when the tension of the latter were lower than that of former. (See Fig. 3. 4 & 10)

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The change of length of several fibers, by twisting on the usual twisting tester under various constant load, are measured by the microscope.
By twisting an amorphous rubber thread shows elongation under the low load, but an crystalline rubber thread, which is obtained by stretching more than 400-500%, shows contraction.
Similarly an undrawn nylon fiber, whose crystallites are oriented randomly in all directions, shows elongation. Isotropic filaments (undrawn nylon) are elongated progressively in several states, and are examined by twisting then under several load. In these case, we found that the elongation of the filament decreases in accordance to their degree of orientation of the crystallites and highly oriented filament shows contraction.
The two-ply yarns, composed with rubber thread or undrawn nylon fibers, show contraction by twisting, but each yarn, which are used for the two-ply yarn, tested separately show elongation.
These facts show that, by twisting, the change in length are positive or negative according to the degree of crystallization and the orientation of the crystallites parallel to the axis of the fibers.

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It is well known that Pauli's test is one of the methods to meauser the degree of wool damages. The presat authors applied this colour reaction to the reduced wool and studied on its mechanisms.
Considerable errors were found in estimating the degree of wool damages by the method, and it was recognized that they owed to the reducing degree of wool samples. When wool is reduced in asidic medium the colouration decreases as the reducing degree of the wool is increased.
It was also found, that this reaction is applicable as a convenient method of estimating the reducing degree of the wool.
Diazo salt treatment for the reduced wool causes the decrease of its sulfhydryl groups content, alkali-solubility and phenol-shrinkability.
Comparing the diazo solt treatment and the hydrogen peroxide treatment, both after the reduction, the former shows a larger alkali solubility and smaller shrinkability than those of the latter for the equal content of sulfhydryl groups in those duple-treated wools.
It seems that these characteristics of the diazo salt treated wool are due to the presense of sulphonic groups in the compound, and the decrease of sulfhydryl groups is due to its phenyl thioetherification by diazo salts.

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From the results of reological studies of high polymers it has been said that the observation of creep behavior is the best way to find the presence of network.
The creep behavior of P. V. A. films without heat-treatment, which sorbed congo red in several concentrations in the dye solution, was observed.
In the low dye concentration the friction between P. V. A. polymer chains decreased in comparison with original P. V. A. film, but in the high concentration, on the contrary, it increased. Recovery behaviors of the creep were also measured, and the same phenomena as above were observed.
From the above results it may be concluded that the network structure is built in P. V. A, film by dye molecules.

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Visco-elastic property of P. V. A. film which container congo red (both of mixed and sorbed states) was measured by means of Vibrating Reed Method. Temperature dependencies of the mechanical loss tangent (tan δ) and real part of complex dynamic modulus (E₁) are shown graphically.
The crystalization of P. V. A. film or fibre in which congo red is sorbed usually did not occur during the heat-treatment. But in our experiment the mechanical properties of P. V. A. film, which contained congo red, changed during the heat-treatment. From this result and our previous reports, it is concluded that the association of dye molecules occurs in P. V. A. film.

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Analysing the rate of dyeing curves of fibres spun with sulphuric acid or sulphuric acid-sodium sulphate baths by means of the method presented in Part I, some essential effects of spinning conditions on dyeing properties were discussed. And the following results were obtained.
In general, the dyeing ability of the fibre gose down and the surface color of dyed fibre becomes light and bright owing to its poor tendency to ring-dyeing by varying the spinning conditions as follows: (1) increasing the age of the viscose; (2) increasing the acid concentration; and (3) increasing the salt (sodium sulphate) concentration.

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The effect of the temperature to the colour in dyeing of cellulose acetate was studied and it was shown by pursueing the change of the maximum purity point in the curve between the luminosity and the purity through the chromatical method that more brilliant colours are generally obtained at the low temperature than high.
This seems to be due to the fact that when the distribution of the dye in the fibre section is observed, the dye concentration at the fibre surface is usually larger in the case of the low temperature dyeing that the high when the total concentration in the fibre is same. More brilliancy is given at the low temperature dyeing that at the high as it may easily be understood from the curve on the luminosity and the purity of the colour given in the pravious paper, No.5.
At the same time the blue dys which seems rather exceptional in the experiments is presumably due to the excessive concentration of the dye in the surface of the fibre beyond the maximum purity point, and it is explained from this point of view that the so-called apparent dyeing, seen often at the pretty low temperature or the early period of the dyeing, may also give darker shades.

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