Method and Apparatus for High Denier Hollow Spiral Fiber
A self-texturing hollow fiber that exhibits a desirable tendency to coil rather than to bend sharply or zig-zag. In one embodiment the invention is a hollow polymer filament having a generally cylindrical cross-section. The filament is further defined by a cylindrical wall formed of at least two generally C-shaped sections, each section including first and second ends separated by an intermediate portion in which no two points along the cross-section of the wall corresponding to the intermediate portion share the same width. In another aspect, the invention is a coiled bilateral hollow polymeric filament in which the two component polymers are identical except for their degree of orientation. The filament is further defined by a non-linear wall formed of at least two non-linear sections.
1 . A hollow polymer filament having a generally cylindrical cross-section, said filament further defined by a cylindrical wall formed of at least two generally C-shaped sections, each section comprising first and second ends separated by an intermediate portion in which no two points along the cross-section of the wall corresponding to said intermediate portion share the same width.
2 . A hollow polymer filament according to claim 1 in which said first end has a first width and said second end has a second width different from said first width.
3 . A hollow polymer filament according to claim 1 in which one side of the hollow filament is more oriented than the other.
4 . A hollow polymer filament according to claim 1 wherein the polymer is polyester.
5 . A hollow polymer filament according to claim 1 wherein the filament is coiled.