Patent ID: 7998387

Claim:
A process for producing a plurality of high strength, high modulus aromatic polyamide filaments, comprising the steps of: extruding an acid solution containing at least 15% by weight of an aromatic polyamide through linearly arranged orifices in a spinneret to provide a warp of filaments; passing the warp of filaments through a layer of non-coagulating fluid into a coagulation bath; and subsequently passing the warp through a spin tube, the spin tube having an elongated cross section with at least two opposite sides being parallel to the filament warp with a length of the at least two opposite sides being at least as long as a width of the filament warp; jetting additional coagulating liquid at a constant flow rate about the filaments in a downward direction at an angle between 15° and 75° with respect to the filaments, wherein: the jetted coagulating liquid moves downward with the warp of filaments through the spin tube at a velocity of about 50% to 100% of a velocity of the filaments, and the coagulating liquid is jetted through a jet channel from either side of the spin tube that is parallel to the filament warp, the jet channel having a width that is equal to or greater than the width of the filament warp.