Prepreg for printed wiring board, printed wiring board using the prepreg and method for manufacturing the printed wiring board, and multilayer printed wiring board and method for manufacturing the multilayer printed wiring board

摘要

A prepreg for a printed wiring board includes fluorocarbon fibers as a reinforcing material, and the reinforcing material is impregnated with a resin. The fluorocarbon fibers include short fibers having a branch structure. The reinforcing material includes a nonwoven fabric formed by interlacing the fluorocarbon fibers in the thickness direction. The proportion of the fluorocarbon fibers among the fibers constituting the nonwoven fabric ranges from 50 wt % to 100 wt %, and the remaining fibers are synthetic fibers or inorganic fibers. The nonwoven fabric is heat-treated at 330° C. to 390° C., then annealed at 200° C. to 270° C., and impregnated with the resin. This prepreg can used to provide a printed wiring board with low Interstitial Via Hole connection resistance and high connection stability and a method for manufacturing the printed wiring board.