Abstract: A synthetic polymer filament is characterized by a four-sided void that extends centrally and axially through the filament. Each apex of the void extends toward the approximate midpoint of one side of the exterior configuration of the filament. The four-sided void has a modification ratio in the range from about 1.2 to about 2.0 and occupies from about five percent 5% to about thirty percent 30% of the cross sectional area of the filament. A spinneret plate for producing the thermoplastic synthetic polymer filament has a cluster of four orifices centered about a central point. Each orifice includes a generally isosceles triangle-shaped major portion from which extends a pair of legs, each leg of one orifice being spaced from the leg of an adjacent orifice to define a gap therebetween.

Abstract: A synthetic polymer filament is characterized by a four-sided void that extends centrally and axially through the filament. Each apex of the void extends toward the approximate midpoint of one side of the exterior configuration of the filament. The four-sided void has a modification ratio in the range from about 1.2 to about 2.0 and occupies from about five percent 5% to about thirty percent 30% of the cross sectional area of the filament.

Abstract: A synthetic polymer filament is characterized by a trilobal void that extends centrally and axially through the filament. Each apex of the void extends toward the approximate midpoint of one side of the exterior configuration of the filament. The trilobal void has a modification ratio in the range from about 1.4 to about 3.0 and occupies from about five percent (5%) to about thirty percent (30%) of the cross sectional area of the filament. At a given constant void percentage a decrease of modification ratio increases the degree of sparkle.A spinneret plate for producing the thermoplastic synthetic polymer filament has a cluster of three generally arrow-shaped orifices centered about a central point. Each orifice is defined by a first and a second outer leg joined together at a pointed end directed away from a central point of the cluster. Each orifice has a central leg extending from the jointure of the outer legs toward the central point of the cluster.

Abstract: Alternate-twist plied yarns, wherein a secondary strand for providing a special effect is plied with at least two alternately, false-twisted primary strands, are made by converging the secondary strand with the primary strands downstream of the point at which the primary strands are converged. The nodes at the twist reversal points for the secondary strand are displaced with respect to nodes of the primary strands. Improved effectiveness from the secondary strand in the plied yarn, such as better antistatic performance, can be realized. Where a node of a secondary strand overlaps a node of the primary strands, whether or not the node centers are displaced, a preferred configuration is one wherein the secondary strand forms a node by wrapping around only one of the primary strands in a portion of the primary node.