| abstract |
(57) [Problem] To provide a prepreg for an inner layer circuit capable of improving adhesion between an inner layer circuit and an insulating layer while maintaining high heat resistance. SOLUTION: An epoxy resin is used as a main agent, a phenol novolak resin is used as a curing agent, and imidazole silane is used as a coupling agent. Using these, a resin composition is prepared. Next, the resin composition is impregnated into a substrate. Thereafter, it is dried. By using a phenol novolak resin, the cured product of the resin composition can have high heat resistance. In addition, with the imidazole silane, high adhesion of the cured product of the resin composition to the metal foil can be obtained. |