An attempt was made to elucidate the effects of an anionic surfactant, sodium dodecyl sulfate (SDS), on the fine structure and mechanical properties of Nylon-6 films heat treated or stretched uniaxially in the surfactant aqueous solutions.
Sample films were unoriented low crystalline Nylon-6 film and those uniaxially stretched under free width by dry-process at 120°C. The concentrations of SDS solutions were 0-0.30 wt. %.
The wet-mechanical properties of the films heat treated in SDS aqueous solutions, such as tensile strength, elongation at break and Young's modulus, were measured in the same solutions at the same temperature. The dynamic viscoelasticity, i.e. the temperature dependencies of dynamic loss modulus E″ and dynamic loss tangent tan δ, were measured at 100Hz using a Viscoelastic Junior Spectrometer. The relation between the crystallization of the film and the addition of surfactantwas investigated by comparing densities and X-ray diffraction patterns. The molecular orientation was studied by measurements of birefringence and X-ray diffraction.
The following results were obtained;
(1) The addition of SDS in the wet-process lowered the wet-mechanical properties of unoriented low crystalline Nylon-6 film.
(2) SDS promoted the diffusion of water into the amorphous region of Nylon-6 film, and suppressed the growth of the crystallite size in the crystallization by the heat-treatment.

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An extended theory of the large deformation mechanics of twisted filament yarns is presented by taking account of the possible change in fiber orientation in the process of elongation. The theory makes it possible to predict the stress-strain relations of twisted yarns based on the orientation distributions of fibers in the unstressed states and on the elongation property of the constituent fiber, without using particular models of the yarn structure such as multi-helix models.
It was found that, in the whole range of yarn strain, theoretical predictions obtained on a few assumptions for the simplicity are in good agreement with the experimental results in the cases of moderately twisted yarns.

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Nylon 66 copolymers were prepared by substitution up to 40 mol% of diacid comonomers: 2, 5-dichloroterephthalic acid (T_Cl2) and 2, 3, 5, 6-tetrachloroterephthalic acid (T_Cl4). The thermal properties measured by DTA were compared with those of previously reported nylon 66 copolymers with terephthalic acid (T) and isophthalic acid (I).
η_sp/C decreases with increasing comonomer content. Melting point depression shows that copolymers with T_Cl2 and T_Cl4 are non-isomorphous. Glass transition temperature (T_g) increases in the order of copolymers with T_Cl4<T_Cl2<I<T, and cold crystallization temperature (T_cc) increases in the order of copolymers with T_Cl4<T<T_Cl2<I. The easiness of crystallization estimated by (T_cc-T_g) decreases in the order of copolymers of T>T_Cl4>T_Cl2>I. Solubility increases by the copolymerization. Flame-retardancy estimated by TG and self-ignition test increases with increasing chlorine content of copolymers.

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A covered yarn is manufactured using the covering machine. The covering yarn is wound on the core under the ballooning tension of which magnitude depends on the air-drag and the yarn mass per unit length. This tension has been analyzed to investigate the mechanical properties of the covered yarn.
The single node balloon formed by the air-drag and the centrifugal force is discussed by using the theoretical equations derived by Mack, in which the Coriolis force is neglected. The theoretical ballooning curve was computed using the air-drag coefficient C_D of cylindrical yarn with diameter d, the specific weight of air γ_a, the yarn mass per unit length m and the radius b of the yarn package. It was found that the computed single node ballooning curve agrees well with experimental results for filament yarn. The tension in the covering process is approximated by the equation T=mω²l²/2 where ω is angular velocity and l is the radius of lashing-end.

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Bleached sulfite pulp was dissolved with formaldehyde in dimethyl sulfoxide, and homogeneous butyration of the cellulose by n-butyric anhydride in the presence of pyridine was examined. Cellulose butyrates with a degree of substitution up to 1.8 were obtained in recovery yield ca. 90%, and were found to be more soluble in various organic solvents than the cellulose acetates with a degree of substitution of 2.0-2.4, prepared with a similar method. The cellulose butyrate film prepared from its acetone solution was colorless and transparent, and not so hard as the cellulose acetate film, and had rather lower tensile strength. The infrared spectrum of the cellulose butyrate was also investigated.

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Rate of fading of fluorescent brightening agents, 1, 2-bis (5-methylbenzoxazolyl) ethylene (1) and its derivatives, increases with an increase in their concentrations both in solution and on polymer film. Such fading behavior is discussed from the standpoints of photoreaction and physical state of the dyes in substrates.
Two kinetic models of the photoreaction process are proposed by assuming the simultaneous trans-cis isomerization and photodimerization; kinetic model (I) postulates that the photoreactions proceed only through the singlet excited state and kinetic model (II) assumes that dye (1) isomerizes through both its singlet and triplet state, but dimerizes only through its triplet excited state. The results obtained by solving the derived rate laws are compared with the experimental results for the ethanol solutions. The fading curve, characteristic fading curve and other experimental results can be well accommodated by the kinetic model (II).

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The kinetics of the dyeing of formalized poly (vinyl alcohol) (PVA) fiber (I) and its acid treated product (II) with three direct dyes have been studied at 70 and 80°C. Each dyeing was made in a finite bath (liquor ratio 1:2000) with 1×10^-5 mol/1 of a direct dye and with 0.1 mol/1 of sodium chloride. The apparent diffusion coefficients (D) (Table 3) decreased with an increase in the degree of the formalization. The values decreased in the order, Rhoduline Red B_??_Orange S>Scarlet 4BS, but the equilibrium sorption of dye (C∞) (Table 2) increased in the reverse order. D and C∞ values for II were fairly larger than those for I. It is suggested that the kinetics of the dyeing of I and II with direct dyes are remarkably affected by the cross-linking formed in the formalization reaction of the polymer and by the chemical constitution and size of the dye molecules.

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For dyed textile articles, the depth of shade is usually classified into dark, medium and light colors, but these terms are very qualitative and their definitions are not clear. However, the depth level has such an important meaning in relation to the tinctorial power of colorants and various fastnesses of dyeings that it should be defined strictly and quantitatively.
The authors compared the visual evaluation of depth level of the systematically composed color specimens with some customary standards of depth level being used in textile industry and reached the conclusion that dark, medium and light colors should have the depth values of C^*=10.86, C^*-5.43 and C^*=2.72, respectively, as the representative values.
It was also shown that the whole range of depth of shade can be divided more rationally by a four classification system, employing dark, medium, light and pale colors than by the usual three classification system.

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