To provide a fine carbon fiber on a mass production scale, having good electrical conductivity and an outer diameter of <400 nm especially of 2-300 nm and used as a filler material with good adhesion to resins or the like, and to provide an field electron-emitting material chemically and thermally stable, excellent in electron emission characteristics and having a long lifetime.
The fine carbon fiber has a multiple-layer structure in which cylindrical carbon sheets overlap each other to form the multiple-layer structure and which center axis has a hollow structure, and has an outer diameter of 2-300 nm and an aspect ratio of 10-15,000, wherein at least one layer of the cylindrical carbon sheet is turned back among the multiple layers at the front end of the carbon fiber to be continuous with another cylindrical carbon sheet, so that the turned back and continuous cylindrical carbon sheet forms a cylinder is open at the front end.
INOUE HITOSHI
SUHARA YUTAKA
Jun Tsuruta
Tetsuji Koga
Masaya Nishiyama
Higuchi Souji