The present disclosure relates to a method for preparing an aramid nanofiber dispersion. More specifically, the present invention relates to a method for preparing aramid nanofibers in a short time from aromatic polyamide-based polymers other than fibers, and to aramid nanofibers prepared therefrom.

An actuator for motor vehicle applications, in particular a motor vehicle door actuator, includes a manually or electromotiveiy operating drive. Furthermore, a flexible drive means which is connected to the drive and can be acted upon by the latter is realized. Additionally provided is an actuating member driven by the drive means. According to the invention, the drive means is produced predominantly from plastic.

An application of a profiled fiber in an infrared radiation material and a textile, wherein a cross-sectional shape of the profiled fiber is polygonal, trefoil, quatrefoil, cross-shaped, double-cross shaped, I-shaped, epsilon-shaped, C-shaped, V-shaped, or hollow. The profiled fiber can be directly used as an infrared material having a high property and has a stable and persistent infrared function without adding an infrared additive.

Embodiments of the invention relate to flame resistant fabrics containing fibers having at least one energy absorbing and/or reflecting additive incorporated into the fibers. Inclusion of such fibers into the fabric increases the arc rating/fabric weight ratio of the fabric while still complying with all requisite thermal protective requirements.

A spinneret is used to reduce filament breakage during spinning of multifilament yarn being stretched at a high stretch ratio. The spinneret has a first group of spinning holes with capillaries and a second group of spinning holes with capillaries. The capillaries of the second group of spinning holes have a lower length to diameter (L/D) ratio than the capillaries of the first group of spinning holes. All of the capillaries have the same diameter, which is 100 m or less.

Fiber for tribological applications, with the exception of mineral fibers, comprising at least one solid lubricant, with the exception of graphite, or boated with at least one solid lubricant, with the exception of graphite.

Provided is a semi-aromatic polyamide fiber having excellent spinning stability, heat resistance and chemical resistance. The semi-aromatic polyamide fiber includes a semi-aromatic polyamide resin having a melting point of 290 C. or higher and a plasticizer having a 5% thermal weight reduction temperature of 320 C. or higher, the resin having as a dicarboxylic acid component an aromatic dicarboxylic acid unit and as a diamine component 1,9-nonanediamine unit and 2-methyl-1,8-octanediamine unit in a molar ratio (the former:the latter) of 70:30 to 99:1.

A crosslinked rubber composition contains a rubber component and para-aramid short fibers having a filament fineness of 2.5 dtex or more and dispersed in the rubber component.

[Problem] To provide: a carbon fiber precursor fiber that can efficiently produce a carbon fiber at a low cost which is excellent in mechanical strengths even without an infusibilization treatment; a carbon fiber; and a method for producing the carbon fiber.

[Solution] A carbon fiber precursor fiber of the present invention includes a polymer containing a constituent unit represented by General Formula (1) below:

##STR00001## where in the General Formula (1), X and Y each independently represent a divalent substituent, a single bond, or a structure forming a fused ring by sharing one side of two adjacent rings, and the divalent substituent is selected from the group consisting of O, S, OSO, NH, CO, CH.sub.2, and CH(CH.sub.3).sub.2.

A fiber-reinforced thermoplastic resin filament is obtained by impregnating a continuous reinforcing fiber with a thermoplastic resin, and satisfies all of conditions (a) to (c). (a) The volume ratio of a reinforcing fiber in a fiber-reinforced thermoplastic resin filament is 30 to 80%; and the volume ratio of a thermoplastic resin in a fiber-reinforced thermoplastic resin filament is 70 to 20%. (b) The thickness of a fiber-reinforced thermoplastic resin filament is 0.01 to 3 mm. (c) The length of a filament contained in a fiber-reinforced thermoplastic resin filament is 1 m or more.