| 摘要 |
PURPOSE:To obtain a sizing agent composed essentially of specific three resin components and a stearic acid ester, capable of forming a carbon fiber strand excellent in resistance to scuffing and producing a prepreg reinforced by the strand and having smooth surface. CONSTITUTION:This sizing agent contains (A) a bisphenol A-type epoxy resin of liquid at room temperature, (B) a bisphenol A-type epoxy resin of solid at room temperature, (C) an unsaturated polyester resin of a condensate of an unsaturated dibasic acid with an alkylene oxide adduct of bisphenol A and (D) a stearic acid ester as essential components, in an amount of 10-50wt.% of component A and 50-90wt.% of component B based on 100wt.% of the total of the component A and the component B. This sizing agent can produce a carbon fiber strand of little nap formation and excellent in resistance to scuffing. When the obtained carbon fiber strand is used in UD prepreg production, a composite having strong shearing force between layers is easily obtained owing to excellent adhesiveness between prepregs. |
