Epoxy Resin Composition with Active Ester and Cyanate Ester for Low Dielectric Loss

The patent uses a composite hardening system combining active ester hardening agent and cyanate ester hardening agent with epoxy resin. This composite material approach creates a multi-functional curing system where the active ester provides adhesion and processability while the cyanate ester contributes to low dielectric loss, achieving both requirements simultaneously through material composition rather than single-material optimization

The patent optimizes the molecular structure parameters of the hardening agents by selecting specific active ester compounds with particular functional groups and cyanate ester compounds with specific aromatic ring structures. By changing the chemical parameters (molecular weight, functional group types, aromatic content) of the hardening agents, the resin composition achieves reduced polarizability and lower dielectric loss while maintaining adequate adhesion and processability

The patent merges the functions of two different hardening agents into a single curing system. The active ester hardening agent provides the necessary adhesion and processability characteristics, while the cyanate ester hardening agent contributes to low dielectric loss. By combining these two agents in specific proportions, the resin composition achieves both low signal transmission loss and adequate peel strength that neither agent could achieve alone

The patent applies different functional properties to different components of the hardening system. The active ester component is optimized for interfacial adhesion and processability, while the cyanate ester component is optimized for bulk dielectric properties. This local optimization of different regions of the chemical system allows the overall material to satisfy conflicting requirements for both strength and low energy loss