CARBON FIBER STRAND

摘要

A carbon fiber strand obtained by impregnating carbon fibers with a sizing agent composition comprising two or more sizing agents each comprising an epoxy resin, wherein the sizing agent composition satisfies the following: when a composition for evaluation prepared by mixing 100 parts by weight of the sizing agent composition with 30 parts by weight of a given hardener is heated at 130°C for 2 hours to obtain a cured article for evaluation and this cured article is examined for dynamic viscoelasticity, then the product of the value of tandelta for the resultant alpha relaxation peak and that of tandelta for the resultant ß relaxation peak, alphatandelta.ßtandelta, is from 0.07 to 0.2. The amount of the sizing agent composition to be infiltrated is preferably 0.3 to 5.0 wt.%.