Systems for producing M yarns, wherein M≥1, include N extruders, M spin stations, and a processor, wherein N>1. Each extruder includes a thermoplastic polymer having a color, hue, and/or dyability characteristic, which are different from each other. Each spin station produces one yarn comprising at least one bundle of filaments. Each spin station comprises at least one spinneret through which filaments are spun from at least two molten thermoplastic polymer streams received by the respective spin station and N spin pumps upstream of the spinneret for the respective spin station. Each spin pump is paired with one of the N extruders. The processor is in electrical communication with the N*M spin pumps and is configured to adjust the volumetric flow rate of the polymers pumped from each spin pump to achieve a ratio of the polymers to be included in each M yarn.

Stretched filaments based on linear, branched or cyclic, aliphatic or semiaromatic polyamides, wherein the filaments have been stretched at a temperature between glass transition temperature and melting point and wherein the filaments are cooled down to room temperature under full tensile load.

Stretched filaments based on linear, branched or cyclic, aliphatic or semiaromatic polyamides, wherein the filaments have been stretched at a temperature between glass transition temperature and melting point and wherein the filaments are cooled down to room temperature under full tensile load.

A thermoplastic resin composition of the present invention comprises: about 100 parts by weight of a thermoplastic resin containing at least one of a polyamide resin and a polyester resin; and about 1 to about 5 parts by weight of zinc oxide, wherein the zinc oxide has an average particle size (D50), as measured by a particle analyzer, of about 0.8 to about 3 μm, and wherein the intensity ratio (B/A) of peak A in a region of 370-390 nm and peak B in a range of 450-600 nm, at the time of photoluminescence measurement, is about 0.01 to about 1.0. The thermoplastic resin composition is excellent in weather resistance, antibacterial properties, mechanical properties, and the like.

An artificial hair fiber suppressed in formation of nodes is provided. An artificial hair fiber is structured with a fiber of drawn resin composition; wherein: when an initial tensile stress of undrawn fiber at 100° C. is taken as F0, and a tensile stress when drawn by 2.5 times is taken as F1, F1/F0 of an undrawn fiber obtained by spinning the resin composition is 1.2 or more.

A breathable water resistant film includes a substrate and a nanofiber layer disposed on the substrate. The nanofiber layer is formed by an electrospinning process. An electrospinning solution used in the electrospinning process includes a first additive, an alcohol, and a second additive. The first additive includes nylon copolymer, and the second additive includes polysilazane.

A breathable water resistant film includes a substrate and a nanofiber layer disposed on the substrate. The nanofiber layer is formed by an electrospinning process. An electrospinning solution used in the electrospinning process includes a first additive, an alcohol, and a second additive. The first additive includes nylon copolymer, and the second additive includes polysilazane.

Provided is an airbag base fabric that has a low air permeability sufficient to ensure the safety of occupants and heat resistance sufficient to withstand high-power, high-temperature gas generated from a recent downsized inflator, and that is capable of being packaged compactly. Also provided is an airbag comprising the base fabric. An airbag base fabric comprising a synthetic fiber multifilament having a total fineness of 500 to 750 dtex, the airbag base fabric having an areal weight of 225 to 245 g/m.sup.2, air permeability at 20 kPa of 0.2 to 0.8 L/cm.sup.2/min, and edgecomb resistance according to the ASTM D 6479 method of 300 to 600 N in both warp and weft directions.

Provided is an airbag base fabric that has a low air permeability sufficient to ensure the safety of occupants and heat resistance sufficient to withstand high-power, high-temperature gas generated from a recent downsized inflator, and that is capable of being packaged compactly. Also provided is an airbag comprising the base fabric. An airbag base fabric comprising a synthetic fiber multifilament having a total fineness of 500 to 750 dtex, the airbag base fabric having an areal weight of 225 to 245 g/m.sup.2, air permeability at 20 kPa of 0.2 to 0.8 L/cm.sup.2/min, and edgecomb resistance according to the ASTM D 6479 method of 300 to 600 N in both warp and weft directions.

Provided are: a filter medium with high dust collection efficiency, low pressure loss, and a long lifespan; and a filter material used for the filter medium. This composite structure includes ultrafine fibers having a fiber diameter of less than 500 nm, and beads. The outermost surface of the composite structure has at least 500/mm.sup.2 of beads with a diameter of 5 μm or more. The ultrafine fibers and the beads preferably have the same component.