Melt-spinnable thermoplastic polymeric filaments are melt extruded from at least one spinneret die plate having at least 25 spinning orifices per square inch of effective spinning area through an airgap of less than 1 inch into a liquid quench medium, for example, water. The surface tension of the quench liquid is maintained at least below 65 dynes per centimeter. The as-spun filaments can have a denier per filament in the range of about 4 to about 600. Polypropylene filaments processed in this manner have an X-ray diffraction pattern for the diffraction angle 2.theta. in the range of 10.degree.2.theta. to 25.degree. 2.theta. characterized by two broad peaks located at about 15.degree. 2.theta. and about 21.degree. 2.theta.; a crystal orientation pattern for an X-ray diffraction angle of about 14.degree. 2.theta. which exhibits a maximum at about the equator; a differential scanning calorimeter thermogram characterized by an exothermic peak at about 90.degree. C.; and a crystallinity of less than 50 percent. The corresponding drawn polypropylene filaments have an equatorial X-ray diffraction pattern for the diffraction angle 2.theta. in the range of 10.degree. 2.theta. to 25.degree. 2.theta. characterized by a single peak located at about 15.degree. 2.theta., and a crystallinity of less than 55 percent.
A synthetic fibre spinning and reeling machine comprising at least one row of spinning units. In each unit the rows of spinnerets and the axles of the rollers and rolls in the finishing and reeling device are disposed transversely to the longitudinal axes of the row of units in which that unit lies. In the case of two rows of units common drive arrangements are provided. The machine provides ready access to the rolls and yet at the same time does not undesirably twist the fibres during their transit from the spinnerets to the rolls.
A zip fastener made of a monofilament of 200 to 20,000 denier composed of a polymethylene terephthalate containing at least 85 mole % of trimethylene terephthalate, tetramethylene terephthalate or hexamethylene terephthalate as a recurring unit, said monofilament having an intrinsic viscosity of 0.35 to 3.5 and a circularity of not more than 1.01. The monofilament is prepared by melt-extruding the polymethylene terephthalate in the form of a filament, passing the extruded filament through an air gap, passing it through a cooling bath of an inert quenching liquid held at a temperature of about 60.degree. to 100.degree.C., then passing it through a cooling zone at a temperature of below 35.degree.C., and then drawing the filament.
Melt-spinning of a fusion melt of an acrylonitrile polymer and water through a crowded hole spinnerette plate having small orifice diameters is achieved using low molecular weight polymer to provide fiber of desirable physical properties.
Fusion melts of acrylonitrile polymer and water are effectively melt-spun through spinnerettes of high capillary density without sticking together of the individual filaments.
Molten polyamide filaments are extruded from spinneret capillaries through a gas-filled gap and into a quench bath which contains a heated aqueous liquid. The bath has a nozzle defining a vertically disposed cylindrical passageway with its entrance in the bath below the bath surface. The filaments are converged into a filament bundle at the entrance and withdrawn from the exit of the passageway at a withdrawal speed of about 1500 to about 3500 meters per minute. The polyamide polymer is extruded from the spinneret such that the jet velocity in the spinneret capillaries is between 2 and 10% of the withdrawal speed of the filament from the exit of the nozzle passageway.
