Ultrahigh strength carbon fibers.

摘要

An ultrahigh strength carbon fiber having a surface layer having a crystalline completeness which is substantially the same as or higher than that of the central region of the fiber, and a functional group amount ratio (O<Sub>ls</Sub>/C<Sub>ls</Sub>) of 0.1 to 0.4 a detected in the fiber surface by X-ray photoelectron spectroscopy, the surface layer preferably having an ultrathin outermost layer having a lower crystalline completeness than the central region of the fiber.