The flow of low density polyethylene from reservoirs into slits at low Reynolds numbers was visually studied, and circulating secondary flows were observed in the reservoir. In this paper, stress patterns in the reservoir were measured by the technique of flow birefringence.
The results are that shear stress is zero both on the centre line between parallel plates and in some place in circulating secondary flow regions. Between these zero shear stress zones, a constant shear stress line lies drawing a loop towards the upstream of the slit. Normal stress difference is zero on the zero order isoclinic fringe lying on the centre line between parallel plates, and in the direction in which the principal stress inclines 45° to the axis perpendicular to the main flow. The absolute stress value is larger on the central side.
Even if a reservoir wall angle is changed, patterns of shear stress and normal stress difference hardly change.

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Experiments were made in the temperature range from 20 to 100°C to determine the frictional force acting on an acrylic filament pulled out from paralleled fiber bundles of cotton, viscose rayon, or polyester fibers, and following results were obtained:
(1) The temperature influence on the frictional force varies according to the kinds of fibers. The friction when pulled out from cotton fiber bundles has the minimum at 80°C, while that from viscose rayon or polyester fiber bundles reaches the maximum at 80°C.
(2) The pulling out frictional force from fiber bundles, f_s; (g/cm), is expressed by the equation: f_s; =K₀; P^a where P (g/cm²) is the external force applied on parallel fiber bundles, K₀; and α are experimental constants affected by the kinds of fibers, temperature, and compressive properties of fiber bundles.

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Viscose rayon fabrics were finished with phosphorus-containing flame retarder (Pyrovatex CP) having methylol groups, with or without melamine form aldehyde resin as co-agent. Content of finishing agents, phosphorus content, oxygen index, and free formaldehyde content were measured. Much free formaldehyde was detected in finished fabrics when treated without soaping. No free formaldehyde and sufficient flame retardancy could be obtained only by such treatment as carried out in highly concentrated solution of pure flame retarder followed by sufficient soaping.

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