The specific thermal conductivity of textile materials in the direction parallel to the fiber arrangement is far greater than that in the direction perpendicular to it. For fabrics in which fibers lie mainly parallel to the surface, the thermal conductivity in the direction parallel to the surface has not been investigated, though that in the direction perpendicular to fabric surface is discussed in detail.
In this paper the specific thermal conductivities of polyester fabrics were measured in the directions parallel to the warp and filling, as well as in the direction perpendicular to the fabric surface. The results were compared with the theoretical values. Measurements of the thermal conductivities and thermal diffusivities were made by the line heat source method reported in our previous paper. The results obtained are as follows:
(1) The theoretical values of the specific thermal conductivities in three directions are in satisfactory agreement with the experimental values for polyester fabrics.
(2) The conductivities of fabrics increase with the increase in bulk densities in the density, range of our tests. The fiber arrangement affects greatly the conductivity. For the filament fabrics of cuprammonium and polyester, the increase in conductivity with applied pressure can be attributed mainly to an increase in bulk density, for there is very little change in fiber arrangement in such fabrics. But for the hairy fabrics of wool, the change in density is counterbalanced by changes in the fiber arrangement. Hence the increase in conductivity of the formers is greater than that of the latters, and for wool flannel, the increase in conductivity in the direction parallel to the warp is far greater than that in the direction perpendicular to the fabric surface.
(3) For the filament fabrics of cuprammonium and polyester, the conductivity in the direction parallel to the warp is three- to five-fold greater than that in the direction perpendicular to the fabric surface. For wool flannel, the conductivity depends little on the directions, because of the random arrangement of the fibers in this fabric.

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This report deals with an experimental investigation on the drawing method of the molten polymer of P. P. by means of an air jet nozzle. Fig. 1 is a structural diagram of the air jet nozzle, which was designed in such a way that the jet air may reach the sonic velocity at nozzle pressures above 2.18kg/cm². The air flow below the outlet of the jet nozzle was observed by schlieren method in the form of shock waves as shown in Fig. 2. In the drawing process, considering the force balance on the running yarn at the point of jet nozzle, the fineness of the yarn should possess a limiting value. Fig. 9 shows the calculated values of the limiting fineness at various positions of the jet nozzle from the spinneret and at various air pressures in the nozzle. Fig. 10 shows the results obtained from the experimental values. These values are compared in Table 1. The load-elongation curves of the yarns are shown in Figs. 13-16, and their birefringenes (Δn) in Figs. 17 and 18.

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The twist distributions along a yarn depends on the properties of the yarn and on the mechanism of yarn-twisting (false twister, open end spinning and ring spinning frame).
In this study, the twist distributions of yarn prepared under the various friction conditions are experimentally investigated, and numerically discussed for the yarn twisted in the high viscous fluid.
The following results are obtained:
1) It was recognized that the twist of the rotating yarn in the fluid distributes along the yarn axis, which is due to the fluid friction.
2) When the twist distribution of the rotating yarn in the fluid is measured under constant tension, the moment of fluid friction M_Y is described by the following equation, in which the flow of the fluid is treated as Couette flow. h_Y: yarn length in the fluid (cm) η: viscosity (dyne•sec/cm²) Ω: angular velocity (rad/sec) R_Y: radius of the yarn (cm) R_P: radius of the pipe (cm)
3) The rigidity of the yarn under constant tension is measured by using the apparatus showing in fig. 3.
4) The rigidity of the yarn depends on twist and tension.

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Experiments were made to observe how the thermal radiation is influenced by the changes of surface roughness and emission area of polymers. These experiments show that, when other conditions are kept unchanged, the increase of surface area is closely related to that of thermal radiation; for thin polymer films, the increase of emission area increases linearly with the increase of thermal radiation energy. When polymer films become thicker, the increase of roughness results in the increase of thermal radiation energy. When polymer films are very thick, the effect of surface roughness becomes small, and the amount of thermal radiation is nearly equal to that of the flat film. The effect of surface roughness is remarkable for such films as the thermal radiation is small when the surface is flat.

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The deposition of ferric oxide particles onto polyester and cotton fabrics in water-soluble polymer solutions was studied in relation to the particle size distribution. Zeta potentials of ferric oxide and the fabrics in the polymer solution were measured. The solutions of sodium carboxymethyl cellulose (NaCMC), polyethylene oxide (PEO) and polyvinyl alcohol (PVA) were examined up to the concentration of about 0.1g/100ml.
The deposition of particles onto fabrics was prevented in NaCMC and promorted in PEO and PVA solutions. By increasing the polymer concentration, the median particle diameter of ferric oxide in both NaCMC and PEO solutions decreased in a similar manner, while in PVA solution it suddenly increased in a dilute concentration region. The particle size distribution was narrower in PEO than in NaCMC solution. Thus, it was found that there is no close relation between the deposition of the particles and their dispersing state in polymer solution.
In NaCMC solution the negative zeta potential of both particles and fabrics increased with an increase in polymer concentration. However, in the solutions of PEO and PVA, the potentials had a tendency to decrease with increasing concentration.
From these results, the mechanism of action of water-soluble polymers on soil deposition onto fabrics is discussed.

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The apparent molal volumes φ₂, and partial molal volumes _??_₂, in aqueous solutions were obtained for NH₄Cl, (CH₃)₄NCl, (C₂H₅)₄NCl, C₆H₅N(CH₃)₃Cl, C₆H₅CH₂N (CH₃)₃Cl, and (C₆H₅CH₂)₂N (CH₃)₂Cl at 25°C and for C₆H₅CH₂N (C₂H₅)₃Cl at 15°, 25° and 35°C. In dilute solution, the sign Sv is found to be negative for all of the salts except in NH₄Cl and (CH₃)₄ NCl.
The values of heat capacity change for the salts in aqueous solution were determined by measuring heats of solution in the temperature range of 5°_??_35°C. ΔC⁰_p values vary from -35.1 to 45.6 cal. deg^-1 mole^-1 in the increasing order of NH₄Cl<(CH₃)₄NCl<C₆H₅CH₂N(CH₃)₃Cl<C₆H₅CH₂N (C₂H₅)₃Cl<(C₆H₅CH₂)₂N(CH₃)₂Cl.
Results are discussed in terms of the influence of the salts on the water structure. All aromatic quaternary ammonium salts except (CH₃)₄ NCl promote the water structure.

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