Distribution of diethylene glycol (DEG) component in the fine texture of polyester fibers has been investigated by measuring the concentrations of DEG in the decomposed and the residual portions obtained by heterogeneous aminolysis of the fibers using monomethylamine. The result shows that the region having higher DEG content decomposes more easily in both fibers of polyethylene terephthalate (PET) and copolyester having DEG as one glycol component.
The tendency becomes remarkable as the temperature of the heat treatment of the fibers prior to the aminolysis is increased. From the analyses of the data obtained by gel permeation chromatography of the residual portion and of the crystallinity by X-ray and infrared spectroscopy, it is shown that aminolysis proceeds successively from the amorphous region where amine can easily pass into. Even in the heat treatment of PET fibers, crystallization occurs by squeezing the DEG rich portion out to the amorphous region, resulting in the increase of DEG concentration in the amorphous region. The change in the dyeing behavior of fibers by heat treatment can be reasonably explained by taking account of the quality change of the amorphous region due to the increase of DEG.

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The purpose of this paper is to make clear the cause of movement of velocity-change-point in the roller drafting zone, because the movement is closely connected with the sliver irregularity delivered. A fundamental means to control the sliver irregularity is proposed.
By using of the theory of velocity-change-point developed by Foster, it is shown that the position of velocity-change-point in the drafting zone is determined by the frictional force between floating fibres and roller gripped fibres. In this case, the characteristics of sliver density in the zone have very important effects on the frictional force. When the variation of sliver density becomes large, the sliver irregularity increases. The fundamental means to control the sliver irregularity is to reduce the variation of sliver density in roller drafting.

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From the viewpoint of the quality evaluation of cigarettes, the firmness of cigarette is one of the most important properties. It has high correlation to physical properties and to the form of the cut tobacco assembly under the compressive condition.
In this report, the effect of the form of shred on the compressive characteristics has been studied for model specimens amenable to mathematical treatments, which were cut out from the uniform sheet reconstituted with the fibrous composition of tobacco leaf, instead of cut tobacco.
The following results were obtained experimentally.
1) The form of shred can be expressed by E_v, the ratio of the exclusive volume to the real volume of specimen.
2) The relationship between compressive stress P and void fraction ε can be expressed by the following equation in the P range of 100-500g/cm²,
P=α(1-ε)ⁿ
where, α and n are constants.
3) The constant n tends to decrease with the increase in E_v.

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Polyvinyl alcohol filaments heated in air at 180°C for 5 or 20 hours were immersed in 80wt% ethylenediamine aqueous solution on a slide glass, and their insoluble surface layers were observed under a microscope. Insoluble surface layers like these were not observed even when the filaments were heated for 20 hours in the atmosphere of nitrogen or under vacuum. Thickness of the insoluble layer was 4_??_5 and 20_??_30μm for the filaments heated in air for 5 and 20 hours, respectively. After a few minutes immersion of the filament in ethylenediamine solution, the insoluble layer of the filament heated for 5 hours swelled, expanding up to 5_??_6 times in diameter, while contracted to a half in length. This insoluble layer separated eventually from the body of the filament. After about one hour, the body itself dissolved away. For the filament heated for 20 hours, the insoluble layer swelled less than that of the filament heated for 5 hours, and did not separate from the body of the filament. But the body dissolved gradually from the surface of the cross sections leaving the insoluble layer. Both filaments heated for 5 and 20 hours were treated in water at 130_??_140°C in an autoclave and were washed by acetone to remove the water. Both residual insoluble surface layers looked like hollow fiber in shape. These surface layers were also examined by a scanning electron microscope, and network pattern cleavages on the surface were observed. These results may show that the formation of the insoluble layer was due to cross linkages introduced into polyvinyl alcohol chains by thermooxydative reactions, consequently leading to decrease in strength and elongation of the fiber heated in air.

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The preparation of the fibrous ion exchangers containing cellulose as reinforcement is studied. Monomer mixtures, such as methacrylic acid-divinyl benzene, are impregnated in di- or triacetate fibers, and polymerized in-fiber. After hydrolysis of the cellulose acetate fibers, though in some cases the hydrolysis is not necessary, ion exchange groups are introduced. The results obtained are summarized as follows:
1) Each type of fibrous ion exchanger, i.e. strong acidic cation exchanger, weak acidic cation exchanger, strong basic anion exchanger, and weak basic anion exchanger, is obtained in good fibrous conformation.
2) The ion exchange capacities measured agree well with the values calculated on the quantity of the polymer introduced in the original fibers.
3) The water swelling property is controllable by changing the degree of crosslinking (DVB%), but for the low degree of crosslinking, it is also influenced by the quantity of the polymer introduced.

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Two kinds of gray scales, one for assessing staining and the other for assessing change in color, have been used currently for judgment of colorfastness of dyeing. These scales are defined by the Adams-Nickerson color difference formula.
In this paper these two gray scales were shown to be written with an equation by using the depth value difference, ΔC^*, defined as
where, N is the fastness rating number (gray color specimen number) and n=10-2N.
The rating of colorfastness could be calculated by using the above mentioned equation. Thus colorfastness could be judged objectively in contrast to the conventional visual method by which the judgment tends to vary depending on individual evaluators.

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The OH proton chemical shifts and the viscosity have been examined for ethylene glycol solutions of urea and thiourea.
The OH proton chemical shifts of ethylene glycol showed an upfield shift in the presence of thiourea and a downfield shift in the presence of urea as described in the previous paper¹⁾, which indicated that urea worked as a structure maker in ethylene glycol and thiourea as a structure breaker. The viscosity data has been interpreted in terms of temperature dependence of the B coefficient, ΔB/ΔT, to find the structural change of ureas-ethylene glycol solutions. This result was similar to that obtained by the proton chemical shifts.
These results suggested that the carbonyl group in urea molecule plays an important part in the increase of the structural regularity of ethylene glycol.

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Bikerman has proposed a relation between liquid drop weight M and sliding angle α when the drop slides down the slope.
(1) L; width of the drop, σ_l; surface tension of water. K is defined as a constant depending on both wetting and roughness. Kawasaki proposed equation (2) for Bikerman's K,
(2) β; Wenzel's surface roughness, θ_a θ_r; advancing and receding contact angle.
However the effect of surface roughness in these equations is not examined yet. The authors examined equation (1) and (2) using glass and polymer surfaces having different roughnesses.
The results show that these equations can be generally applicable to hydrophobic surfaces (glass coated with a fluorochemical, polystyrene and cellulose triacetate), but not to rather hydrophilic surfaces (polyvinylchloride and cellulose diacetate).

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