A New Flame Retardant 1,2-Polybutadiene Laminate

A flame retardant 1,2-polybutadiene laminate with excellent dielectric properties and high heat resistance has been developed for high density multilayer printed wiring boards. A high molecular weight 1,2-polybutadiene is selected as a base material to provide prepregs with a bnon-tacky property without semi-curing of the resin. A low molecular weight 1,2-polybutadiene is used to control the resin flow property of prepregs. The desirable flame retardation is achieved while maintaining the excellent dielectric and thermal properties of 1,2-polybutadieney using a new halogenated bisphenol methacrylate compound. The 1,2-polybutadiene laminate exhibits a low dielectric constant (ε = 3.4) and dissipation factor (tanδ=0.004) and a flammability classification of UL94 V-1. Also, it has a solder resistance at 300°C for over 120 s. The 1,2-polybutadiene multilayer printed wiring board shows no occurrence of resin smears and excellent transmission characteristics, and demonstrates high reliability of interconnectionn between plated-through-holes and internal layers against thermal shock.