The effects of ripening degree of viscose, conc. of acid, (NH₄)₂SO₄, ZnSO₄ etc. in coag. bath, on the surface structure of regenerated viscose films were observed using an electron microscope. The smoothness or coarseness of surface of films are not only effected by the conc. of acid and salts in coag. bath, but the stability of xanthate. For instance, when the coag. bath of high ZnSO₄ content is used, a stable zinc xanthate film is formed and the surface of regenearated film becomes very coarse, owing to delayed decomposition.

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Steeping process was investigated by means of floating pressure determination and following results were obtained.
1) Behavior of pulp sheet with regard to flotation in industrial steeping condition is estimated by the standard floating pressure determined experimentally using sheet sample of convenient magnitude.
2) Fairly long time is necessary for the completion of mercerization reaction of pulp in sheetform steeping, and its incompletion affects the properties of alkali cellulose and viscose produced therefrom. Extent of mercerization reaction in steeping process can be followed by the floating pressure determination.
3) Floating-up tendency of a pulp sheet is minimized at a proper lye filling speed, which varics with pulp sheet quality.
4) The higher the moisture content, the larger the floating-up tendency of pulp sheet is, in the range of moisture content 4-14%.

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Changes in fibre structure of regenerated cellulose fibres such as degree of crystallinity and lateral order and cross-sectional shape, by treatment with aqueous alkali of various concentrations have been investigated experimentally.
Rayons of two types were used and compared; fibre S, ordinary viscose rayon having irregular section and non-uniform distribution of lateral order, Fibre X, special viscose rayon having uniform round section and uniform single-peak lateral order distribution.
Both fibers showed increases in crystallinity, after swelling and deswelling, but the magnitude of the change in low ordered fibre (S) was much greater. The skin effect of this fibre disappeared and the distribution of lateral order shifted to highly ordered level and showed similar curve to that of Fibre X.
Changes in physical properties of fibres by swelling treatment were also observed, and discussed on the relation between fibre structures and mechanical properties. It was concluded that physical properties of Fibre X are closely associated with crystalinity and orientation, whereas those of Fibre S are much more markedly effected by the skin-core structure.

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According to acetylate cotton linter, we have observed following three cellulose acetates; the degree of acetylation 59.17%, 57.4% and 54.9%.
The first one was fractionated with methylene chloride-ethanol and the rest with acetone-ethanol.
The acetates were saponified with 20% ammonium hydroxide and the nitrates made by nitration of the regenerated cellulose were fractionated with acetone-ligroin.
In a comparison between distribution curves of nitrates and of acetates, it was shown that the fractionation of the nitrates gave more precise result than that of the acetates themselves.
In the distribution curves the high DP portions decreased with the time of saponification.
A non-uniformity coefficient increased in early stage, but decreased with the proceeding of sapo-nification.
We investigated the results of the experiments after Beall-Jörgensen theory, and assumued that the hydrolysis of glucoside linkage takes place at random in initial stage of saponification, but not at random after the hydrolysis proceeded.

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To express the looseness of cotton on the basis of the porosity of sample, theoretical formula were developed as formula (2) from D'Arcy's law and Kozeny's equation on laminar air flow through the sample of cotton. In the formula (2) c; Kozeny's constant, λ; porosity of sample, s; specific surface of material, w; weight of sample, q; air flow rate passed through sample and p; pressure difference between front and back of the sample.
By using the apparatus showed in Fig. I and varying the weights and porosities of samples from three diffrent kinds of cotton, some characteristic results were obtained as follows:
(1) If the weight and porosity of one kind of sample are eqaul, values of q/p are constant.
(2) If the weights of the same sample are equal, values of q/p are related to λ_x.
(3) In the same kind of material, values of wq/p are correlated to λ_x.
(4) When the porosity of one sample is equal to that of another of different kinds of materials, values of wq/p are proportional to 1/s².
(5) Irrespective of the kinds of materials, values of s²wq/p in each sample are related to λ_x only.
(6) The curve between λ_x and 1/c plotted from experimental results and by the formula (1) is nearly equal to E. Lord's curve.
(7) C is expressed as the function of s²wq/p.
Then, the experimental result betweee C and s²wq/p is shown by formula (10). From (2) and (10), λ_x and the looseness of cotton O_x are shown by formula (12), (13).

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It is said that the magnitude of raising power depends upon the magnitude of relative velocity between the cloth and the point of raising wire of the counter pile roller, and then the cloths are raised by this sliding action. In the practical raising operation, however, I cannot recognize that there is the sliding action and the magnitude of raising power is equal to the magnitude of raising effect.
The writer concludes that by the differential motion, the counter pile rollers are rotated with the cloth and with the belt band, then the difference of rotation counts reduce to the raising power and the counter pile rollers drive on the cloth without sliding, when the points of the raising wire leave for the cloth, the fibres are digged upon. Moreover, the raising effect depends upon the contact times of the wire point on the definite length of the cloth.
Further, it is not discussed yet how the running direction of the raised pile arises in the practical application. If we considered it merely by the relative velocity between the cloth and the poin of wire, it should be the reverse of the practical raising result.

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