Patent ID: 11898276
Assignee: FORMOSA PLASTICS CORPORATION, U.S.A.
Field: Textile and paper machines (Mechanical engineering)
Classification: CPC D | IPC D

Claim 0:
1. A method of forming a carbon fiber, comprising:
dissolving a polyacrylonitrile copolymer in a solvent to obtain a dope;
performing a spinning process to the dope, thereby obtaining a filament tow;
oiling the filament tow to obtain a filament with oil by using a finishing oil, wherein a surface tension (σ) is in a range of 30 mN/m to 70 mN/m, and the surface tension and a particle size (R) of the finishing oil satisfy following equation:

20<σ+(R/2)0.5<60;

performing a compacting drying process to the filament with oil, thereby obtaining a filament; and
performing a firing process to the filament, thereby obtaining the carbon fiber.