Phenol-water mixture separates into two phases below 68°C in a certain range of concentration, but phenol-methanol-water mixture does not above a certain concentration of methanol. The fractionation of cellulose triacetate by phenol-methanol-water mixture at 25°C is studied in this experiment, where phenol-methanol-water (60:16:24) mixture is used as solvent, methanol-water (40:60) as precipitant. The fractionation method is the so-called “solution extraction” i.e. the most part of triacetate is precipitated, redissolved by heating up to 50°C, then the solution is let cool naturally over one night separating into two phases. The upper phase containing a small part of triacetate of the lowest DP is taken out, and the triacetate is precipitated, washed, dried, and weighed. The lower part is redissolved clearly by adding some phenol solution and two phases separation is repeated.
By this fractionation method, three samples of triacetate are compared on the uniformity of DP-distribution. The triacetate of ZnCl₂-solution method has the highest uniformity and the triacetate of ZnCl₂-vapour phase method the least.

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In order to clarify the spinning mechanism of viscose rayon, several xanthate filaments are spun from viscoses containing amine, the internal structures of which are investigated by measuring swelling value, stress-strain curves, %-orientation-strain curves, stress relaxation, % orientation relaxation, and elastic part of deformation.
It is observed;
(1) amine has some effects upon the formation of junction points.
(2) the microstructures of xanthate filaments such as strength of junction, partial orientation of molecules derived from junction point are chiefly affected by the nature of junction point.
(3) the degree of swelling itself does not appear so closely related with these properties in our experiment.

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The effects of several treatment on twist moment of polycaproamide (Amilan) mono-filament are measured.
The heat-treatment with 20% extension affects the increase in twist moment, but the heat-set without restriction affects the decrease in moment.
Although the phenomena are inconsistent with those of J. J. Mertens, the results may fully be explained by the theory advanced in the previous paper.
By the heat-treatment with extension of the filament, the crystallites are subdivided and packed closely, so that the crystal slippage becomes difficult, while the crystal growth in the heat-set without restriction affects easy slippage and relaxes the twist moment.
When the sample is simply stretched to its breakage the fiblization of fiber is progressed and its twisting behaviour has resemblance to that of multi-filament yarn.

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The paper is concerned with an investigation of the relationship between withdrawal force and pulling speed of a single fiber from parallel fiber bundle in a channel, subjected to external load.
Experimental apparatus which modified those of Postle-Ingham s²⁾, are shown in Fig. 3_??_1. Experimental materials are 3 denier viscose rayon Fibres.
When the values of applied load R and pulling speed υ are fixed, observed valuse of the withdrawal force f are distributed broadly, for example, as the curves in Fig. 3_??_8. From the experimental results (see Table I) the following relationship between mean withdrawal force f_m and pulling speed υ are obtained:f_m=AlogBυWhere parameter A and B are functions of applied load R.
In this paper, also, the relation (3_??_8)′ are discussed theoretically, based on the stochastic process theory of breaking phenomena of matter.⁴⁾

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Utilizing an Instron tester, the shapes of the pressure-deformation curves for blankets and carded fibre mass are mearsured.
They are fitted by the equation P: Where pressure, x: deformation a₀ and B: constants.
Applying a model which consists of m(x) springs in series and the n(x) serial springs in parallel, to samples, we derived the pressure-deformation equations. The theoretical equations include the arithmetical expressions described by several workers and show satisfactory agreement with the observations.

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Fibers, made from polyesters of β-hydroxyethoxy aromatic acids, and their copolyester, and those from polyethylen terephthalate (PET), were treated with aqueous caustic soda solutions.
Rate constants of solution, k (g/hr/cm²), are calculated from the equation
where x is the loss of weight by solution, d₀ (cm) the initial diameter of a fiber, t (hr) the treatment time, and ρ (g/cm³) the density of the fiber.
At room temperature, k of fibers from polyester A and coplyester are much smaller than those from polyethylen terephthalate, but higher the temperature, they become closer. Draw ratio and heat-treating temperature have some influence on k, but chemical constitution of polyesters have much more.
We conclude that k, rate constants of solution, are most influenced by the rate of hydrolysis of ester combination of the molecular chains on the surface of fibers. The differences of k, caused by chemical constitution of polyesters, may be explained by Hammet's Law.

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The effects of some softeners upon raw silk, degummed silk and some other fibres were investigated.
1) Raw silk is much softened by the treatment with the solution of softeners, but in the case of other fibres there seems little or no softening effects on their filaments.
2) The softening effect of nonionic softeners on raw silk is small, but it is large in the cases of cationic as well as anionic softeners.
3) The filaments of viscose rayon and heat-treated PVA fibre are softened by the treatment with solution containing softeners, but the cause does not seem to lie on the softners.
4) With the exception of raw silk, the effect of softeners upon the fibres, as generally recognized, seems to be caused by the lowering of the interfibre friction.

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The dyeing of the new synthetic fibers which show no affinity for dyestuff should be considered from different standpoint.
The dyeing of these synthetic fibers is thought to be mechanical treatment of carrying dyes into the inner part of fiber rather than the chemical combination of dyes with fibers.
The affinity of polyester fiber for dyes was given by introducing metallic ions under pressure.
Tetoron, a commercial name of polyester fiber, having a rigid construction, is used in these experiments, and Cr ion was fed in the form of the aqueous solution of K₂Cr₂O₇. The results obtained are as follows;
(1) Cr absorption with time and temperature. The quantity of Cr absorbed by this fiber increases with time and temperature from the solution of the definite Cr concentration. (Fig. I)
(2) Equilibrium absorption of Cr ion with Tetoron. The results are shown more fully in the form of Freumdlich absorption equation (Fig. 3) than in the form of Langmuir equation. (Fig. 4).
(3) Cr absorption with the concentration of H₂SO₄: Cr absorption by tetoron increases with increasing H₂SO₄(Fig. 5)
(4) Removal of Cr in tetron by boiling in water, About 9% of the absorbed Cr in tetoron is washed out by boiling in water for thirty houres. (Fig. 6)

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The electrostatic charge on wool is mainly related to the scales of wool fibers and to the surfactants with which the wool fibers are treated. Thus the influences of various surfactants are due to the following two factors:
1) The pH of the surfactant solutions. (a) The damage of wool fiber by alkalis and acids. (d) The transformation of the properties of wool by the amphoteric character of its. Own.
2) The state of adsorption of the surfactants and counter-ions on wool fibers.
When the wool fibers are treated with various surfactants after alcohol-benzene extraction the electro static charges and their electric resistance are measured.
The result are as follow: The non-treated wool has the largest electrostatic charges and electric resistance.
Poly oxyechylene glycol type nonion, L, MS, ABS, AS, and H are the medians and soap is the smallest to those properties.

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Viscose and PVA films are dyed by such dyes as Direct Violet 2R, Japanol Violet J, Chrome Violet BC and Neolan Violet 3R, and also PVA Films are colored by some acid dyes as Orange II and Azo Eosine.
Changes in absorption spectra of these films by dry heating are studied and the following results are obtained:
a) No deformation of the absorption curves is observed by dry heating in the cases of dyed viscose films.
b) By the dyeing of PVA films the new absorption is developed to red side of the maximum wave length. The new absorption (shoulder) is decreased by dry heating in the case of Direct Violet 2R, and color change is observed, but in the cases of other dyes it is not observed.

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