| abstract |
A multiple-layered printed wiring board is manufactured, which exhibits higher thermal resistance and lower thermal expansion so that no flaking and/or no crack would be occurred in a thermal shock test such as a cooling-heating cycle test and the like, in addition to exhibiting a fire retardancy. The resin composition is capable of being employed for forming a resin layer of a resin-attached metal foil or an insulating sheet of a base material-attached insulating sheet, and includes: a cyanate resin and/or a prepolymer thereof; an epoxy resin substantially containing no halogen atom; a phenoxy resin substantially containing no halogen atom; an imidazole compound; and an inorganic filler, and also directed to a resin-attached metal foil formed by cladding a metal foil with such resin composition, a base material-attached insulating sheet formed by cladding an insulating base material therewith, and a multiple-layered printed wiring board, formed by laying such resin-attached metal foil(s) or such base material-attached insulating sheet(s) on a single side or both sides of an internal layer circuit board, and hot pressure forming thereof. |