Cationic epoxy molded electronic (Cemtronic) technology and its applications

The characteristics of an aromatic sulfonium fluoro antimonate salt which promotes the homopolymerization of epoxies is introduced. The influence of various epoxy resins, epoxy diluents, and inorganic fillers on the reactivity of this sulfonium salt are discussed. The uniqueness of this sulfonium salt is its attended stability at room temperature and instant reactivity towards epoxies at >70/spl deg/C. Additionally, only a small amount of this sulfonium salt is needed to cure epoxies. This so called "Cemtronic catalyst" has been utilized in the electronic, electrical encapsulating and casting areas. Properties of a Cemtronic encapsulating product and a Cemtronic casting system are discussed and compared with a traditional anhydride cured epoxy system.