A two-component curable epoxy resin system including a dye solution. The resin system includes an epoxy resin component containing at least 80% by weight of a polyglycidyl ether of a polyphenol. The system also includes a hardener mixture containing mainly polyethylene tetraamines. The system includes triethylene diamine in specific amounts as a catalyst. The system has beneficial curing characteristics with desired color that make it useful for producing fiber-reinforced composites in a resin transfer molding process.