An imide prepolymer comprising specific bismaleimide and diamine components in a specific molar ratio cures into a product having improved dielectric properties, heat resistance, and bond strength. An encapsulating composition for semiconductor packages is obtained therefrom. The prepolymer is used to form prepregs from which laminates useful as multilayer printed circuit boards are manufactured.  
                            由特定摩尔比的特定双马来
酰亚胺和二胺成分组成的
亚胺预聚物可固化成具有更好的介电性能、耐热性和粘合强度的产品。由此可获得一种用于半导体封装的封装组合物。该预聚物可用于形成预浸料,用其制成的层压板可用作多层印刷电路板。