Epoxy resin composition, a prepreg, a method and its manufacturing fiber-reinforced composite material

The present invention, component A: an epoxy resin having no sulfur atom in the molecule, and component B: an epoxy resin composition containing an imidazole compound represented by the following formula (1), component C: the following formula imidazole compounds represented by (2), or a component D: among the epoxy resins having at least one sulfur atom in the molecule, characterized in that it comprises at least one component, relates to an epoxy resin composition. According to the present invention, excellent storage stability at room temperature, a relatively low temperature, and can be heated and cured in a short time, it is possible to provide an epoxy resin composition having a resin has high heat resistance after curing. (In the formula, R1 represents a linear or branched alkyl group having 1 to 5 carbon atoms, a hydroxy methyl group, R2 is an alkyl group or a hydrogen atom, straight or branched C1-5 It represents. embedded image wherein the, R3 represents an organic group containing at least one carbon, R4-R6 represents a hydrogen atom or a methyl group or an ethyl group.)