| 摘要 |
<p>Provided are carbon fiber bundles which have high knot strength even if the single fiber fineness is large, and which have excellent handling properties and processability. The carbon fiber bundles have a single fiber fineness of 0.8-2.5 dtex, knot strength of 298 N/mm 2 or greater. This method of producing carbon fibers having knot strength of 298 N/mm 2 or greater involves a heat treatment step for heat treating, for 50-150 minutes, specific polyacrylonitrile-based precursor fiber bundles described in the description in an oxidizing atmosphere rising in temperature in the temperature range of 220-300°C.</p> |
