| 摘要 |
PROBLEM TO BE SOLVED: To obtain a milled carbon fiber capable of producing e.g. reinforced composite materials of high uniformity, excellent in fluidity and dispersibility by making a prescribed amount of a sizing agent adhere to carbon fiber, followed by subjecting the add-on to reduction adjustment and then cutting the resultant fiber into a prescribed length. SOLUTION: This milled carbon fiber is obtained by making >=0.1 wt.% of a sizing agent adhere to carbon fiber derived from polyacrylonitrile-based fiber, continuously feeding the carbon fiber into a heating oven whose internal air atmosphere is kept at 300 to 700 deg.C while maintaining the amount of the carbon fiber at 0.1 to 8 kg per m<2> of carbon fiber surface, subjecting the add-on of the sizing agent to reduction adjustment to <0.05 wt.% by heating, and then cutting the fiber into a fiber length of <=1 mm, thus obtaining the objective milled carbon fiber whose fiber length and aspect ratio are 3 to 500μm and 1 to 70, respectively. |
