A recycled polyester filament and preparation method therefor are disclosed. In the process of preparing a fiber from a recycled polyester according to the FDY process, the ring-blowing is used for cooling, and the distribution of spinneret holes on the spinneret is controlled to meet certain conditions, then the recycled polyester filament is obtained by relaxation heat treatment after a fully drawn yarn is produced. The spinneret holes are C-shaped spinneret holes and circular spinneret holes, the cross-section of the C-shaped spinneret hole is composed of an outer arc, an inner arc, and two line segments, and two endpoints of the outer arc are A and B respectively; wherein the certain conditions include: all the spinneret holes are distributed in concentric circles, and the C-shaped spinneret holes are located on the outermost circle, rotating at different angles and randomly distributed.

A recycled polyester filament and preparation method therefor are disclosed. In the process of preparing a fiber from a recycled polyester according to the FDY process, the ring-blowing is used for cooling, and the distribution of spinneret holes on the spinneret is controlled to meet certain conditions, then the recycled polyester filament is obtained by relaxation heat treatment after a fully drawn yarn is produced. The spinneret holes are C-shaped spinneret holes and circular spinneret holes, the cross-section of the C-shaped spinneret hole is composed of an outer arc, an inner arc, and two line segments, and two endpoints of the outer arc are A and B respectively; wherein the certain conditions include: all the spinneret holes are distributed in concentric circles, and the C-shaped spinneret holes are located on the outermost circle, rotating at different angles and randomly distributed.

Various implementations include a melt-spun filament that has a radial cross section that has two substantially parallel linear perimetrical sections and first and second curved perimetrical sections. The first curved perimetrical section extends between first ends of the linear perimetrical sections, and the second curved perimetrical section extends between second ends of the linear perimetrical sections. The curved perimetrical sections are convex. According to some embodiments, the curved perimetrical sections are semi-circular or semi-elliptical. A plurality of melt-spun filaments may be included in a bundle of filaments and/or a yarn made with the melt-spun filaments. In addition, a spinneret plate for spinning the melt-spun filaments and a method of making the melt-spun filaments is also provided.

Various implementations include a melt-spun filament that has a radial cross section that has two substantially parallel linear perimetrical sections and first and second curved perimetrical sections. The first curved perimetrical section extends between first ends of the linear perimetrical sections, and the second curved perimetrical section extends between second ends of the linear perimetrical sections. The curved perimetrical sections are convex. According to some embodiments, the curved perimetrical sections are semi-circular or semi-elliptical. A plurality of melt-spun filaments may be included in a bundle of filaments and/or a yarn made with the melt-spun filaments. In addition, a spinneret plate for spinning the melt-spun filaments and a method of making the melt-spun filaments is also provided.

A woven fabric is provided that is advantageously used for sportswear such as down wear, a down jacket, a windbreaker, a futon, a sleeping bag, rainwear, a tent, a bag, and a rucksack, and materials thereof, and that has a high tear strength, assuredly maintains a low air-permeability, and has a good abrasion resistance while the fabric is lightweight and thin. The woven fabric comprises a synthetic multifilament comprising a modified monofilament having a filament transverse cross-section of a substantially quadrilateral shape, wherein: the synthetic multifilament has a total fineness 5 to 60 dtex; the modified monofilament has a single yarn fineness of 1.0 to 7.5 dtex; the woven fabric includes the synthetic multifilament in an amount of 45% or more by mass relative to 100% by mass of the woven fabric; and an average contact length where the modified monofilament touches a modified monofilament adjacent thereto is 8 to 40 μm on a cross-section in a direction perpendicular to the synthetic multifilament.

An artificial turf filament comprising an ethylene-based polymer, wherein the ethylene-based polymer comprises greater than 50 wt. % of the units derived from ethylene and less than 30 wt. % of the units derived from one or more alpha-olefin co monomers.

A preparation method of self-crimping elastic combined filament yarns for knitting is disclosed, wherein the combined filament yarns are extruded from the same spinneret; a first fiber-forming polymer melt is divided into two ways, one is directly extruded after distribution; and the other is extruded after distribution by side-by-side composite spinning together with a second fiber-forming polymer melt; the first fiber-forming polymer and the second fiber-forming polymer are compatible or partially compatible; on the same spinneret, a ratio of the number of spinneret holes m for direct extrusion to the number of spinneret holes n for extrusion after distribution by side-by-side composite spinning is 1:(5-10); the self-crimping elastic combined filament yarns for knitting are prepared according to specific spinning processes, wherein the combined filament yarn mainly comprises a first fiber-forming polymer monofilament and a first/second fiber-forming polymer side-by-side composite monofilament; wherein the monofilament crimping directions are randomly distributed.

A preparation method of self-crimping elastic combined filament yarns for knitting is disclosed, wherein the combined filament yarns are extruded from the same spinneret; a first fiber-forming polymer melt is divided into two ways, one is directly extruded after distribution; and the other is extruded after distribution by side-by-side composite spinning together with a second fiber-forming polymer melt; the first fiber-forming polymer and the second fiber-forming polymer are compatible or partially compatible; on the same spinneret, a ratio of the number of spinneret holes m for direct extrusion to the number of spinneret holes n for extrusion after distribution by side-by-side composite spinning is 1:(5-10); the self-crimping elastic combined filament yarns for knitting are prepared according to specific spinning processes, wherein the combined filament yarn mainly comprises a first fiber-forming polymer monofilament and a first/second fiber-forming polymer side-by-side composite monofilament; wherein the monofilament crimping directions are randomly distributed.

A method of forming a color-changing fiber that can be incorporated into fabrics and other woven materials. The color changing fibers include an annular wall and a conductive wire axially extending through the annular wall, a core strand surrounded by the annular wall and extending axially through a central portion of the fiber, and an encapsulated electro-optic medium disposed on a surface of the core strand.

Various implementations include a method of forming a bulked continuous filament (BCF) yarn. The method includes providing N molten streams of polymer, providing M spinnerets, and spinning the N molten streams of polymer through the M spinnerets. At least a first group of filaments and a second group of filaments are spun through the M spinnerets. The first group of filaments each have a first average denier per filament along a length of the filaments and the second group of filaments each having a second average denier per filament along a length of the filaments, the first and second average denier per filament being different. The method further includes combining the filaments from the M spinnerets together and texturizing the spun filaments.