Changes in optical behaviours of cross sections during the drying process of the freshly coagulated viscose filaments, were examined with a polarizing microscope. Then the orienting effects of compression caused by progressive shrinkage during the first drying process are discussed fundamentally in relation to the distinctive structure of fresh filament, which seemed to be of essential importance for fibre formation.

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Although various theories respecting the course of skin formation in viscose fibres have been proposed, a satisfactory answer to this question cannot yet be obtained. The author indicated previously that viscose fibres have the multilayer structure consisted of the alternative succession of α-type and β-type layers which differ in crystallinity, and that a difference in degree of lateral order is not, as Morechead suggested, the main feature of the skin effect (see rf. 1).
The author's further studies concerning the course of fibre formation, developed concretely in this paper, show that the formation of a skin is closely related to the orientation resulting from the colloid-chemical effects accompanied by the α-and-β periodic coagulation. In other words, a difference in degree of orientation between skin and core comes from the essential compressive effects caused by shrinkage with the formation of α-and-β multilayer structure, and not directly, as Preston believed, from the mechanical actions such as drawing and stretching. A possible mechanism for skin formation is suggested and the relationship of fibre structure to shape of fibre section is discussed briefly.

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Copolyesteramides were prepared from β-hydroxy ethyl ammonium sebacate and a salt or monomer such as aromatic amino acid or aromatic hydroxy acid. The salt was prepared from monomer such as diamine or dicarboxylic acid containing aromatic nuclei and monomer of aliphatic dicarboxylic acid, aliphatic diamine or ethanol amine.
m-xylylene diamine, p-xylylene diamine and p-phenylene ββ'diethyl amine were employed as. aromatic diamines. Terephthalic acid, isophthalic acid and p-phenylene diacetic acid were employed as aromatic dicarboxylic acids. p-amino benzoic acid and p-hydroxy benzoic acid were employed as aromatic amino acid and aromatic hydroxy acid respectively.
The properties of copolyesteramides such as fibre forming and melting point were examined, Except for copolymer system of p-xylylene diamine and p-phenylene ββ'diethyl amine, ideal copolymer systems could not be prepared from above compounds because of disappearance of the fibre forming properties. In the case of copolymer system of p-aromatic diamine homologues, it was found that melting points of the copolymers are almost in a straight line drawn between melting points of two pure polymers, showing the maximum difference in almost 1:1 copolymerization ratio. Melting points are always higher and the difference is slight. The fibre forming and hot drawing properties of the copolymer system are satisfiable.

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Copolyesteramides were prepared from β-hydroxy ethyl ammonium sebacate and aliphatic polymethylene monoammonium sebacate and the relation between the copolymerizations ratios and melting points of their copolymers was studied. Ethylene diamine and tetramethylene diamine were employed as aliphatic diamine.
Though melting point of the copolymers were slightly higher than the ideal melting point, they are almost in a line as a whole, as in the case of p-aromatic diamine. Furthermore, in the case of aliphatic polymethylene diamines which were composed from 6_??_12 methylene groups except for 9 methylene groups, the same tendency was found.
It was shown from the results of X ray diffraction pattern that the representative copolymers i.e. 1:1 and 1:7 copolymers, possessed a high crystallinity and an orientation.
These results suggest that aliphatic and p-aromatic diamine are favourable as a component of copolymer system in copolymerizing with β-hydroxy ethyl ammonium sebacate.

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Second order transition temperature (T_g) melting temperature (T_m) and thermosetting temperature of copolymers were determined by dilatometric and linear expansion methods. Two kinds of copolymers were prepared from β-hydroxy ethyl ammonium sebacate (I) and tetramethylene diamine monoammonium sebacate (II), their molar ratios were 1:7 and 1:1 respectively.
T_m of poly-(I) by dilatometric method was 121°C, but T_g could not be found at the range of above -35°C. The expansion curve of filament which prepared from 1:7 copolymer showed an unstable tendency with rising temperature, and the tendency disappeared after the thermosetting. The thermosetting which increases the density owing to the crystallization was accomplished within a comparatively short time, and the optimum thermosetting temperature was 170_??_180°C. T_g and T_m of these thermosetting filaments were 55_??_57°C and 241°C respectively, and the results satisfied the equation T_g=(2/3)T_m. In the case of block prepared from 1:1 copolymer, T_m was 204°C, and the expansion curve showed a turning point at Ca. 7°C, but the turning point could not be confirmed as T_g value.
T_g of 1:7 copolymer determined by the linear expansion method was 70°C.

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In order to determine the molecular weight distributions of the low molecular parts of rayon and pulp, fractional solution and combined method of extraction and fractional precipitation for nitrated sample were investigated. The results are as follows:
(1) Molecular weight range of fractionation results obtained by fractional precipitation was wider than that of fractional solution.
(2) Between the nitrated sample forms of powder, thin film and fiber for fractional solution, the result which resemble most to fractional precipitation was obtained by the film.
It may be considered that crystallinity of sample is destroyed during dissolution of the sample and preparation of the film and so the equilibrium relating to the degree of polymerization is easily attained. The effect of surface area of the filmed sample is small.
(3) Equilibrium, which is estimated by change of extraction weight, was more rapidly attained with 88:12 aceton-water mixture, but much longer time is required for 35:65 ethyl acetateethanol and 35:65 butyl acetate-ethanol mixture.
(4) As much time is required to obtain the equilibrium, stepwise fractional solution is laborious. With respect to the solvent in the rapid method, in which the low molecular fraction is extracted at first and then solution is fractionated by precipitation method, aceton-water mixture gives an agreed results with that precipitation method, but ethyl acetate-and butyl acetate-ethanol mixture showed a deviated results from that.

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To determine the factor, on which the dissolution of hemicellulose at the steeping process depends, molecular weight distribution and chemical composition of dissolved hemicellulose (acidprecipitable cellulose) were studied.
The results are as follows:
(1) Dissolution of hemicellulose depends chiefly on the swelling degree of the pulp in the case of sheet, and on the molecular weight of the hemicellulose in the case of slurry steeping.
(2) As mannan and xylan dissolves preferentially in steeping lye, the chemical composition of pulp also affects on dissolution of hemicellulose.
(3) The solubility of hemicellulose shows a minimum with steeping temparature but various pulps show different curves. The solubility of hemicellulose decreases over the whole molecular weight range similarly, and the solubility of mannan and xylan also decreases at minimum.
(4) The solubility of hemicellulose decreasses with increase in concentration of hemicellulose and alkali (from 18% to 20%) of steeping liquor over the whole molecular weight range.

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The compression-recovery behaviours of the bulks of the Angora rabbit fibre were observed in: distilled water at 30±1°C. Three maximum pressures of 5.0, 10.0, 18.5g/cm² were used and the-pressure effects were examined. The following results were obtained:
(1) The more the pressure added, the smaller is the recovered height.
(2) In order to compare the compression behaviours of the bulk, the maximum pressure added must be higher than a certain critical value in our samples 0.5 g/cm², otherwise the compression is disturbed by the nonhomogeneities of the test bulk.
(3) When a cyclic compression-recovery is added repeatedly several handred times to a bulk, its deformation loop becomes practically constant. The deformation of this bulk proceeds further by the compression under at higher pressure, but not with a lower pressure even repeatedly.

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The cyclic compression-recovery behaviours of Angora rabbit fibre bulks were observed in the distilled water at three temperatures, 30, 45 and 60±2°C respectivery; the maximum pressure was 10.0g/cm² in all cases. The results were compared with those of other literatures concerning to the felting.

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Cyclic compression-recovery behaviours of Angora rabbit fibre bulks were observed under 10.0g/cm² maximum pressure (at 30±1°C and at pH1.1_??_9.2). The results were compared with those of wool reported in the literatures.

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1. In a previous report, one of the authors^* estimated the necessary activation energy E of the baking reation of resin finishing as approximately 16_??_18kcal/mol, based on data derived from commercial products. The activation energy E and frequency factor A of the reaction presented in this report are calculated by using our experimental measurements. For this purpose, we have made two series of experiments: a) baking of resin on clean glass plates, and b) baking of resin on cotton fabrics.
2. Our experimental results fully agreed with the following equation of unimolecular reaction: where a: Unreacted part of resin i.e. in 70°C water soluble part at z=0 by Kyeldhal method. a-x: do. at z=z (min.) k: Reaction velocity constant at temp. T°K z: Baking time (min.) z₀: Waiting time (min.)
3. In all the experiments, the reaction velocity constant k fully agreed with the Ahrrenius equation: ln k=A+(-E/RT) where R: gas constant.
4. From the said results, the activation energy E and frequency factor A are culculated as follows: for series a) E 8.82kcal/mol, A 2, 178 10^-1 min. for series b) E 18.85kcal/mol, A 1, 012 10^-1 min.
5. We have further made cumulative baking at various temperatures and have found that experimental results agreed with the cumulative reaction equation:
6. We conclude from the great difference of the activation energy E in the above two series, that in series a) only reaction between resin components occurs, whereas in series b) reaction between resin components and cellulose predominates.

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It is well known that the crabbing is a process to set wool fabrics in weak basic aqueous soltion, but on pre-dyed fabrics acidic dyes are desorped through this treatment. So, authors tried to set the worsted fabrics on acidic side by using mercapto acid solution named “Cold Set Solution”.
Results obtained are as follows.
1) Although the bath temperature of thioglycollic acid (T. G. A.) treatment was lower than the case of crabbing, T. G. A, treatment set plainly the wool fabrics under tension. On severe conditions this treatment gave the setting effect for fabric texture but anti-shrinkability was lowered, Rinsing and hydrogen peroxide treatment after the reduction treatment promoted the anti-shrinkability. The wool fabrics treated alone in T. G. A. solution had higher anti-shrinkability than those treated in basic T. G. solution, but this order was reversed by hydrogen peroxide treatments respectively after reducing.
The necessary quantity of T. G. A. into wool to set was about 10mg equivalents/100g wool.
2) when the wools reduced on acidic and basic sides showed the same alkali-solubility, the former contained more quantity of T. G. A, than the latter. Other anionic ions in T, G. A. bath decreased the adsorption of T. G. A. by wool, but those in basic T. G. bath gave little effects.
Hydrogen peroxide acted more effectively for the wool reduced with T. G. in basic solution than in acidic, while the rinsing was effective for the wool reduced in reduced in acidic. Therefore, it seems that the rinsing effect is caused by the desorption rather than by the oxidation of T. G. A. contained excessively in the reduced wool.
From the facts mentioned above, some differences in mechanism between acidic T. G. A. and basic T. G. treatments on wool was noted.

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