Patent ID: 9376765
Filing Date: 2016-06-28
CPC Classification: D01F,Y10T

Claim Text:
1. A method for producing a carbon fiber having a lattice spacing (d 002 ) of 0.336 nm to 0.338 nm and a crystallite size (Lc 002 ) of 50 nm to 150 nm as measured and evaluated by X-ray diffraction and an average fiber diameter of 10 nm to 500 nm, the carbon fiber having no branched structure, said method comprising: (1) a step of forming a precursor fiber from a mixture made of 100 parts by mass of a thermoplastic resin having a melt viscosity of 5 to 100 Pa·s as measured at 350° C. and 600 s (2) a step of subjecting the precursor fiber to a stabilization treatment to stabilize the thermoplastic carbon precursor in the precursor fiber, thereby forming a stabilized resin composition; (3) a step of removing the thermoplastic resin from the stabilized resin composition under reduced pressure which is 0.01 to 5 kPa, thereby forming a fibrous carbon precursor; and (4) a step of carbonizing or graphitizing the fibrous carbon precursor.