Dry-spun hollow polyacrylonitrile fibres and filaments and process for the production thereof

US4483903A · kind A · utility

Assignee

• BAYER HEALTHCARE LLC · DE

Inventors

• Ulrich Reinehr · Dormagen, DE
• Kurt Bernklau · Dormagen, DE
• Hans K. Burghart · Neuss, DE
• Toni Herbertz · Dormagen, DE
• Hermann-Josef Jungverdorben · Dormagen, DE

Key dates

• Filing date: Sep 6, 1983
• Grant date: Nov 20, 1984
• Expiry date: Sep 6, 2003

Classification

• Technology area (CPC Y): Emerging Cross-Sectional Technologies
• CPC primary: Y10T428/2975
• WIPO field: Textile and paper machines
• WIPO sector: Mechanical engineering

Abstract

Hollow acrylonitrile fibres and filaments are prepared by dry spinning the spinning dope through a nozzle having loop-shaped nozzle orifices, the solution having a viscosity equivalent to at least 120 falling ball seconds, measured at 80.degree. C., or at least 75 falling ball seconds, measured at 100.degree. C., wherein the nozzle orifice area of the profiling nozzle is smaller than 0.2 mm.sup.2 and the maximum width of the sides of the loop-shaped nozzle is 0.1 mm and the overlap between the two ends of the sides of the loop-shaped nozzle forms an angle of from 10.degree. to 30.degree. measured from the center of the nozzle and wherein the spinning air acts on the filaments in a transverse direction to the filament take-off and the air direction forms an angle of from 80.degree. to 100.degree. with a straight line passing through the opening between the sides.