Patent · US Expired

Process for preparing a carbon fiber of high strength

US4925604A · kind A · utility

1Cited by
7References
3Claims
0Family size

Assignee

Inventors

Key dates

Filing dateOct 15, 1985
Grant dateMay 15, 1990
Priority date
Expiry dateOct 15, 2005

Classification

  • Technology area (CPC D)Textiles; Paper
  • CPC primaryD01F9/22
  • WIPO fieldTextile and paper machines
  • WIPO sectorMechanical engineering

Abstract

A carbon fiber of high strength is disclosed, each filament of which is substantially circular in its cross-section but which has circumferential ruggedness which extends in parallel to an axis of the filament to form pleats. The ruggedness has a depth of more than 0.1 .mu.m. The carbon fiber is prepared by extruding a spinning solution of an aqueous polyacrylonitrile/pure zinc chloride solution of a specified polymer content into a coagulating bath at a specified draft ratio, followed by washing, drying and stretching at a total stretching ratio of 10-20 folds to form a precursor which is then subjected to conventional stabilizing and carbonizing steps.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.