| 摘要 |
PROBLEM TO BE SOLVED: To provide a fiber bundle of carbon fiber precursors capable of producing a carbon fiber bundle having good resin impregnating property and fiber openability and high strength.SOLUTION: The fiber bundle of carbon fiber precursors made of a plurality of single fibers and the single fiber made of an acrylonitrile-based polymer, where the ratio of a major diameter to a minor diameter (major diameter/minor diameter) of cross section of a single fiber is 1.35-1.5, the maximum height (Ry) of surface of the single fiber is 0.42-0.6 μm, and Ry/(major diameter/minor diameter) is 0.31 μm or above. |
