The weight percent and absolute weight of wax in lint during the growing process of cotton fiber were daily measured in order to make clear the distribution of wax in cotton fiber. From this series of experiments, it may be concluded that the wax is the surface constituents of cotton fiber and exists only in the primary wall of the cotton fiber and can not be found in any appreciable amount in the inner structure i.e. the secondary wall of cotton fiber.

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Heat-treated and unheated polyvinyl alcohol fibers are acetalized with terephthaldehyde.
The acetalization is peculiarly influenced by concentration of surfuric acid used as catalyst. As the concentration is increased, the initial rate of reaction becomes greater, but the subsequent rate is more rapidly decreased, and the apparent equilibrium degree of reaction seems to be lower.
The wet-heat resistance of acetalized fiber is chiefly determined by extent of reaction rather than by conditions of reaction, differing from the case of acetalization with glyoxal. When the heattreated fiber is acetalized to several, ten or more, or about twenty mole per cents fiber can resist to water of 100°. 120°_??_130°. or 140°C respectively. Where the percentage is computed from weight increase due to the reaction by assuming that all bound terephthaldehydes are cross-linked between molecules of polyvinyl alcohol. When even the unheated fiber is acetalized to twenty or more mole per cents, it resists to water of 100_??_140°C. These results show that terephthaldehyde cross-links much more readily than glyoxal.
The tensile recovery of the acetalized fiber is very high, but the tenacity. the breaking extension and particularly the knot strength generally tend to decrease as compared with formalized fiber, though the extents of these decreases depend on the concentration of sulfuric acid in the acetalizing bath. The unusual effects of the concentration of sulfuric acid on the rate of reaction and on the tenacity and extension seem to be due to differences of distribution of the crosslinks within fiber.

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We found a relation between characteristic retardation time (logτ) stress (S g/d) and absolute temperature (T°K) represented as follows.
logτ=-22.7-10.0S+11.1×10³/T
The stress and temperature dependences of instantaneous elastic elongation E₀, retarded elastic elongation E₁/2, maximum elongation velocity (dr/d log t) max. and scale factor for generalization, f are also discussed in the present article.

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Generally high polymer solution indicate macroscopic heterogeneous dispersed state. The distribution of size of these undissolved gells and physico-chemical properties may be different. So when the dissolving properties of such solution are to be estimated from their filterability, it would more reasonable to deduce it from the change of filterability constant K obtained from several rather than just one filtering test. General filtering behavior of cellulose acetate solution by constant pressure filtering method with several filtering media is discussed in the paper.

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By counting continuously the numbers of component fibres of the blended yarns, their interactions have been studied. The blended yarns of cotton and rayon s. f. producted by mixing in the drawing process have been used in the test. The results obtained are as follows.
(1) A considerable difference may be seen between CV of the blend in an ideal case, and in the experimental case though the tendency is similar, and therefore it is probable that this is due to their interactions.
(2) In general, for two different component fibers, the influence of grosser fibre denier may be extremely great on both the yarn evenness and the blend irregularity.

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We devised an appratus, by which we observed the behaviour of structural shearing deformation of fabrics dynamically. This behaviour relates to the three factors-elasticity, viscosity and friction-, and shows non-linearity which depends upon the amplitudes i. e. deformation, and it can be divided into three zones according to the degrees of deformation.
When very small, deformation depends upon only yarn bending without relative sliding between warp and weft yarns at their crossing points. Therefore the apparent elastic modulus of shearing deformation is very high.
When the deformation increases and surpasses such a critical value as the Bingham point, both yarns begin to slide relatively, and its behaviour apparently shows linearity. As this deformation further increases the behaviour deviates from the linear relation again, and cubic buckling appears.
The behaviours of a glass cloth and a saran screen can be modelized as truss and rahmen respectively. Apparent elastic modulus of elasticity and frictional force of cotton plain fabrics increases in proportion with cover factors and tensions applied to the sample fabrics.

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High α pulp is treated with sodium hypochlorite, varying the amounts of active Cl₂, and the turbidities produced during the acetylation of the treated pulp were studied. In the sodium hypochlorite treatment of the high α pulp, the cuprammonium viscosity decreases and the carboxyl content increases in proportion to the increase of the amount of the active Cl₂, although these are in the opposite direction in the low Cl₂ concentration. These phenomena show that the action of the sodium hypochlorite treatment upon the pulp may be the process of purification, oxidation and degradation. Although the effect of the sodium hypochlorite treatment is thus complicated, it is confirmed that the sodium hypochlorite treatment, when used in an ordinary bleaching condition, had little effect on the turbidity produced during acetylation. It is very interesting that the increase of the amount of β-cellulose has little effect on the turbidity, although it might be interpreted as the result that the effect of carboxyl group could be neglected as the increase of the amount of this group is rather small.

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The auther discussed in previous papers the mechanism of the crease resistant finish with the uncondensed urea formaldehyde solution from the results obtained in previous paper on the relations betweeen the treating conditions, the resin content of the fabric, the retained resin and the properties of the treated fabric, i. e., the crease resistancy, strength, elongation, non-swelling property, and pointed out that the formation of the chemical cross linkage between cellulose molecules is a cause to give the crease resistance to the fabric, but the main cause is the deposition of resin in the amorphous region of fibre.
Resin should be deposited firmly and have a good water resistance, and is not to be deposited between the micell of the cellulose molecule physically, but with the formation of the physicochemical cross linkage of resin by the formation of co-ordinate link to the hydroxyl groups of cellulose molecule.

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The result that the measuring method of swelling degree of resin-treated fabrics was relatively more accurate than other methods was found. This paper deals with the intrinsic cause given to the mechanism of resin treated fabrics by these five detecting methods.

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Experimental data for absorption on cotton at 90°C with three dyes, Aizen Direct Blue BBH (C. I. No.406), Diamine Blue 3B (C. I. No.477) and Nippon Sky Blue (C. I. No.520) (which differ only slightly in structure, being derived from benzidine, tolidine and dianisidine respectively coupled with H acid) was analysed by the Donnan treatment of Neale et al.. The value of the absorption constant k and the volume of the surface phase of the fibre was determined from the results of the experiment. It was found that the volume of the surface phase increases with increased concentration of the dye. The data of low dye concentrations are analysed by the Donnan treatment using the volume term of 22g/100g cotton, whereas at high dye concentrations it is necessary to use a much larger value of 42g/100g cotton. This value of 42g/100g cotton is in close agreement with the date Boulton et al. for the amount of water imbibed by American cotton.

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