Heat effect of the unoriented amorphous polyethylene terephthalate fibers with different degrees of polymerization and orientation were observed by specific gravity, birefringence and X-ray before and after the heat treatment.
As for the heat effect,
a) the crystallization was recognized by specific gravity and X-ray diffraction,
b) the birefringence changed from positive to negative and
c) the perpendicular orientation was proved by X-ray diffraction and birefringence, and then, the degree of perpendicular orientation was found proportional to the degree of the polymerization and orientation.

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The unoriented amorphous polyethylene terephthalate (PET) fibers were immersed in the several reagents, and were observed the changes of birefringences, specific gravities and X-ray diffractions.
The results observed are:
(1) Generally birefrigences decreased but after immersion in acetone and nitric acid they sometimes increased.
(2) Specific gravities increased and phenomena of crystallization were confirmed by X-ray Examination.
(3) Shrinkage at immersion varied with the degree of polymerization but it hardly changes with birefringences.
(4) From the structures of the reagents which affect the unoriented amorphous PET, the compounds with similar structures to PET, and nitro radical etc. Which activate the benzene ring are effective.

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The physical properties and behaviours of the isotropic xanthate filaments during their gelatination, conversion to cellulose and drying, were studied, in relation to the means by which coagulation is brought about (coagulant, temperature, degree of ripeness of viscose). In this paper, the following are examined; shrinkage behaviours during each proce_??_, diffusion rate of regenerating solution into xanthate gel, rate of regeneration, and diffusion coefficients of solute in developing fresh and reswollen cellulose gels.
On consideration of these data, the structure of primary xanthate gel is discussed. And the present data would give some valuable suggestions respecting the orienting effects of compression during the fibre setting-up process-coagulation and first drying process.

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(1) For the purpose of determining cellulose structure (crystallinity) of moist or wet cellulose fibres, such as freshly spun rayon, the modified iodine absorption method, that is based upon Hessler & Power's technique, is presented.
(2) Using some regenerated cellulose fibres, which differ in stability of cohesive structure, comparison of the results obtained by iodine absorption method with those of hydrolysis method for determining crystallinity was carried out. And iodine absorption before and after depolymerizing treatment (acid hydrolysis) was taken as a measure of recrystallization of cellulose.
(3) Degree of recrystallization which occurs in acid solution is conclusively determined by degree of order or stability of cohesive structure present in original fibre; the extent of recrystallization during hydrolysis (1% H₂SO₄, 95°C, 5 hrs) was estimated at 30% for high tenacity rayon (after first drying), 40% for ordinary rayon (after first drying), and 65% for freshly spun ordinary rayon (before first drying).
(4) For cellulose fibres of which cohesive structures are set in stable state, such as rayon after first drying, iodine absorption and hydrolysis methods show good agreement in placing the fibres according to their relative crystallinity in order. But for fibres having unstable cohesive structure, such as freshly spun rayon, hydrolysis method gives very high values for the reason of a remarkable recrystallization effect, and shows opposite results to indine absorption method in placing the fibres according to their relative crystallinity in order.
(5) The iodine absorption method is useful in detecting changes in cellulose structure occurred during first drying of freshly spun rayon or in alkali-treatment of rayon.

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A red pine pulp for viscose rayon and a raw cotton were hydrolyzed with 4 N HCl, and the average degree of polymerization (DP) and DP distribution of cellulose crystallites produced were determined. Although the average DP's were 100_??_150, the maximum DP's were 300_??_500 resulting in considerable non-uniformity of chain length distribution. When hydrolyed under the same condition, the hydrolyzed rayon pulp had a little more non-uniformity of chain length distribution than that for the hydrolyzed raw cotton, especially in the initial stage of hydrolysis.
In order to explain slow decrease of average DP, the decrease of high DP fractions and the increase of low DP fractions, a new concept for hydrolysis of cellulose crystallites was postulated, according to which, the crystallites have cracks located with irregular intervals and perpendicular to cellulose chains. The cracks occur at the disordered portion of cellulose chains or weak points in cellulose crystallites. However, the splitting of the crystallites through the cracks may take place very slowly, since the decrease of high DP fractions with the hydrolysis is slow. Peeling off reaction of cellulose chains from the surface of the cellulose crystallites may be the main reaction of acid hydrolysis.

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Zeisel's method depends upon the formation of methyl iodide when the unknown is heated with hydroiodic acid. The methyl iodide is removed from the reaction flask with a current of carbon dioxide into absorption vessels where it is finally absorbed in a solution of alcoholic silver nitrate, the methyl iodide being decomposed with the formation of silver iodide. The silver iodide is then recovered, weighed, and the methoxyl content calculated by means of suitable conversion factors.
However, silver nitrate can not be used, if samples contain sulfur compound. Then, modified pyridine method was adopted.
Methyl iodide is absorbed in pyridine instead of silver nitrate solution and the methyl iodide is decomposed with the formation of methyl iodide pyridinium salt.
As the methyl iodide pyridinium salt has maximal absorbency at 366 mμ and the absorbency at 366mμ increases with content of methoxyl group, methoxyl value in samples is rapidly and accurately determined by the absorbency at 366 mμ.
It is determined that molar extinction coefficient of methyl iodide pyridinium salt is 6.2×10².

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The unbleached beech sulphate pulp of maximum screened yield and that of lower screened yield were bleached to the same brightness (Hunter 80) by means of five-stage bleaching. The chemical and mechanical properties of those pulps were examined.
Besides, the difference between sodium hydroxide and carbonate treatment after chlorination was studied. The permanganate number of the pulps after alkaline extraction, the change of pH of the extracting liquid during alkaline treatment and the chemical and mechanical properties and the brightness of the bleached pulps were observed.
1. It is economically profitable that when the unbleached beech sulphate pulp is used as unbleached pulp the cooked pulp showes Roe number 4_??_5 and maximum screened yield, and when the beech sulphate pulp is used after bleaching the cooked pulp showes lower Roe number than 4_??_5 and lower screened yield than the maximum screened yield.
2. Sodium carbonate can be used instead of sodium hydroxide in the stage of alkaline treatment. Consequently, the bleaching of the sulphate pulp is possible to be carried out more economically than using sodium hydroxide. But if the washing of the chlorinated pulp is insufficient, hydrochloric acid remains in the slush and this results in carbon dioxide which may cause forming trouble in mill operation.

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The displacement of dyed fibers that had been inserted into sliver before drafting, were measured. Then the destributions of velocity-change-points for the case of various fiber length were investigated.
In case of long fibers, the center of distribution is at near side of front roller, but for short fibers, it is at far side. (Fig. 1) The distribution range and the variation of center become larger as the fiber length becomes shorter. (Fig. 2) (Fig. 3)

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The sams experimental method was used. Dyed fibers were inserted into sliver as in Fig. 1, and the distribution of velocity-change-points for the case of various position in sliver were investigated.
The centers of distribution are indpendent of the position, but the distribution range and variation of center are large at the surface or side of sliver against the center. (Fig. 2) (Fig. 3).

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Effets of pH value of wool setting bath are studied by determining shrinkage by soaking for wool fabric and using fibers bundles for wool fiber as previously reported. Setting velocities of wool fibers in setting bath of various pH values, were studied, and correlations of fibers and fabrics for each pH values of setting bath are discussed. And the effects of pH values of soaking buth are also studied.
(1) Shrinkage of fabric by setting is dependent on pH value of setting bath, and it becomes remarkable in high value of pH, especially in high temperature. This phenomenon is peculiar to fabric, but it does not appeared in fiber.
(2) Effects of pH value of setting bath to a set of wool fabrics are dependent on temperature of setting. For example, setting effects increase suddenly at 9 of pH value at 40°C, 7 to 8 at 70°C, and 3 to 4 at 100°C, respectively.
(3) Extremely similar results are observed on setting of wool fibers, and therefore, good correlations may be assumed between fabrics and fibers as to the effects of pH values of setting bath, except in (1) above.
(4) The following experimental formula between set of wool fiber and time of treatment may be derived:
S=k+αlogt where, S represents set, t time of treatment, k and α constants related to pH value and temperature of setting bath, respectively. Physical meanings and calculated data on k and α, in various conditions of pH values and temperatures of setting bath, are discussed.
(5) It is not admitted the special value of pH of setting bath, in which the maximum effect of setting was observed.
(6) Even in acidic condition of setting bath, especially in high temperature, different values of set are obtained, in accordance with pH values of setting bath. It is explained from differences in decrease of opportunities of relinkings of side chaines, due to blockings of amino groups by hydrogen ions which varies in accordance with pH balues of setting bath.
(7) On effects of pH value of soaking bath, maximum set is found in 5 of pH value, isoelectric point of wool fiber. It is explained from bonds scissions in various of pH.

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Effects of cooling conditions in hot water setting of wool fabrics, especially the temperature of cooling water and mechanical properties of treated fabrics are studied. The results are analysed by comparing the similar experiments on single fibers and changes of stress in cooling process of setting which have important roles on setting. The results are as follows:
(1) Temperature of cooling water does not effect on the set, when the specimens are dried under fixed condition after cooling.
(2) The maximum set is obtainable at 20°C of cooling water, when the specimens are dried under free condition. These are explained from the changes of stress in cooling and the diminish of set in wet state prior to drying are dependent on temperature of water for cooling.
(3) Stress for 5% stretched single fiber rises suddenly on cooling after treatmed in hot water, and it is largest at 70°C of hot water treatment. On grey fabric, it is largest at 55°C, and when temperature of hot water is above 75_??_80°C, stress drops reversely on cooling. These variations are analysed from contractive force due to entropy effect which depends on temperature and formations of crosslinks by cooling.

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The mutuality of the physical properties such as the crease resistance, the imbibition value and the elasticity of the plain viscose rayon fabrics treated with the formaldehyde solution of various concentration and the effect of the amount of bound formaldehyde to these physical properties were examined. Then the effect of repeated soaping for these physical properties and for the formaldehyde content of the fabrics were observed. The following results were obtained.
(1) The change of the physical properties of the fabrics, due to the treatment with formaldehyde, was very remarkable up to 4% of bound formaldehyde, but over this point the change of these properties was scarcely observed inspite of the increase of bound formaldehyde.
(2) The improvement of the crease recovery and the decrease of the imbibition value of the fabrics were proportional to the increase of the elastic recovery of the fibers.
(3) The reduction of the amount of bound formaldehyde and the change of the physical properties by repeated soaping scarecely occurred.
(4) From these results, it was confirmed that in the case of the formaldehyde treatment, the improvement of crease resistance of the fabrics was caused, as reported by many wokers previously, by the formation of the cross linkage between two hydroxyl groups of adjacent cellulose molecules.

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The coagulation value of direct dyes was determined. The coagulation value decreases in the following order. Nippon Sky Blue (C. I. No.520)> Aizen Direct Blue BBH (C. I. No.406)> Diamine Blue 3 B (C. I. No.477)> Dianil Azurine G (C. I. No.502)> Congo Red (C. I. No.370)> Benzopur purine 4 BKX (C. I. No.448), Azo Blue (C. I. No.463)> Azoorseillin. The standard affinity of these dyes for cotton first increases with decreasing the coagulation value and then decreases. The abnormally low coagulation value of Azoorseillin and Azo Blue is to be attributed to the chelate structure in these molecules.

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Viscose films are dyed by such direct dyes as Benzo Azurine G, Chlorazol Sky Blue FF, and Dianil Blue G, and also by copper complex dyes derived from above dyes.
Before and after exposing the dyed films to light of a fade-o-meter, absorption spectra are measured in the vissible region. The spectra change produced by exposure to light for different intervals of time continued until 127 hrs. indicates that the optical density of the normal dyes decreases with time of exposure and becomes to about a half of before exposing at 127 hrs. exposure, while the decrease of the density of the complex dyes is only about 10-20%. When the dyed films are treated with a 1% CuSO₄ aqueous solution, the light fastness is improved for the normal dyes but is not changed appreciably for the complex dyes.

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