The conditions of occurrence of the transverse lines that appear in polyethylene terephthalate fibers as a result of uniform extension, and their transformation by annealing and swelling are studied by optical and electron microscopy. Their fine structures are investigated by small-angle X-ray scattering and stress-strain curves.
The results are as follows:
(1) Draw ratio and load at which the transverse lines first make their appearance depend on drawing temperature and speed. It is concluded that occurrence of these lines is closely related with molecular orientation and these lines first appear at birefringence about 0.17.
(2) The transverse lines appear both outside and inside of the sample. The density of the sample which has the transverse lines increases gradually as the transverse lines become progressively more intense. The transverse lines in this case are not voids.
(3) The transverse lines disappear by annealing and swelling of samples. In swollen samples, however, new transverse lines occur by the longitudinal shrinkage with swelling.
(4) Regardless of the presence of transverse lines, no difference in the fine structure between the samples are found by small angle X-ray scattering.
(5) There is a remarkable change in the stress-strain curves of the samples with the transverse lines. Occurence of the transverse lines makes clear the secondary yield point of the stress-strain curve of the samples.
(6) It is infered that these lines derive from the macroununiformity of density or tension caused by uneven draw ratio in the sample highly drawn and orientated. The sources of occurrence of these lines are thought to be the structures with ununiform density that exist originally in undrawn samples or that occur during the drawing.

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Adsorption behaviours of various surface active agents, anionic, cationic and nonionic, were studied by the microelectrophoresis. It was found that, when polar groups of surface active agents were the same, the free energy of adsorption increased with increasing chain length, and was greater for anionic than for cationic surface active agent. No difference was found between adsorption behaviours of surface active agents, unlike those of thorium ions on sericin A and B.
The nonionic surface active polymers of the pluronic type, EPAN's, were found to behave as anionic surface active agents, when their effect on uncovered sols were examined. However, no adsorption was found to take place on sol particles covered with sericin.
Electron micrograph showed that the morphology of the coagulum of silver iodide sol covered with sericin, obtained by the addition of ionic surface active agents, was very different from that obtained by the direct addition of sericin or inorganic electrolyte to the silver iodide sol uncovered.

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A modified polyvinyl alcohol containing 5.25 mol% of hydrazide group in the polymer chain was prepared by the reaction of vinyl acetate-acrylamide copolymer with hydrazine hydrate. Similar polyvinyl alcohol containing 1.05% of nitrogen was readily obtained from commercial polyvinyl acetate by the hydrolysis with hydrazine hydrate.
Thermal stability of films derived from these nitrogen-containing polyvinyl alcohols was studied by means of ultra violet, infrared and X-ray measurements and differencial thermal analysis. It was found that the polymers are sufficiently stable and scarcely colored by the heat treatment at 200°C for 20 hours.
Water resistance of these films determined by measuring the swelling index at 30°C and solubility at 70°C was improved. The films after formalization showed good mechanical properties and excellent dyeability. The mechanism of contribution of hydrazide group in the polymer to the thermal stability is discussed.

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The effcts of total load, hardness of roller cover and speed of cloth on the water retained in fabric after mangling ware investigated. At first, a three-factor factorial experiment in a parametric model was used. In this experiment factor A (total load) has 8 levels, factor B (cloth speed) 5 levels and factor C (cover hardness) 4 levels, and entire experiment is replicated seven times. The results of analysis of variance show that factor A and C are highly significant but B is less when using a 1% level of significance. Next, the principal factor analysis is used to determine the minimum number of dimensions needed to account for the variance in the original set of variables. In this analysis the numbers of dimension of variable spaces are 96 (total load 8, speed 3, hardness 4) and 36 (total load 3, speed 3, hardness 4), respectively.
It is confirmed that 75% of total variance is explained sufficiciently with three eigenvalues in the order of reducing magnitude.

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The formation of complex of acid dye with tannic acid (chinese gallotannin) was evidenced by the existence of isosbestic point in visible absorption spectra of the aqueous solutions of various compositions. The molar ratio of the complex was determined with the continuous variation method in electro-conductivity. In order to elucidate the interaction mechanism between acid dye and tannic acid, several organic compounds with similar structure to tannic acid were used. The acid dyes used were Orang II (C. I. Acid Orange 7) and Diacid Supra Red 3 B (C. I. Acid Red 35). Both of these dyes, in spite of having different chemical structure, formed 1:1 complex with tannic acid (gallic acid residue) as well as with pyrogallol or phloroglucin, whereas they formed 2:1 complex with gallic acid or benzoic acid. From these experimental results it is deduced that the complex formation between these acid dyes and tannic acid occurs principally by hydrogen bonding between nitrogen atom of azo group of the dyes and phenolic hydroxyl group of tannic acid, or possibly by bonding of charge transfer or van der Waals type between dye molecule and gallic acid residue of tannic acid.

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Cotton fabrics were treated with diglycidyl ether (Epoxide I) and with glycerin diglycidyl ether (Epoxide III) at different temperatures (20_??_80°C) in the presence of different amounts of sodium hydroxide under wet conditions, and the reaction kinetics and the relation between the wet wrinkle recovery angle and the degree of the reaction of the epoxy group were investigated.
The reaction of Epoxide I obeys well first-order kinetics with respect to the epoxy concentration. The degree of the reaction increases progressively as the catalyst concentration increases. The following empirical relation was found to exist between the wet wrinkle recovery angle (W, warp + filling) obtained by the treatment and the degree of the reaction of the epoxy group (x, %) where W_L is the maximum wet wrinkle recovery angle obtainable (assumed to be 320°), and W₀ is the wet recovery angle of the control fabric (200°). The k′ value increases as the concentration of the catalyst is decreased and as the reaction temperature lowered. It is considered that the k′ value indicates the effectiveness of crosslink formation in the reaction of the epoxy group. The larger the k′, the more the crosslink formation.
The reaction of Epoxide III, which contains a hydroxy group, does not obey the first-order kinetics. The relation between W and x can be expressed as follows except for the treatment_??_at 80°C:
The A value varies with the concentration of the catalyst and the reaction temperature.

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