Synthesis of high purity o-cresol formaldehyde novolac epoxy resins

Polymer Bulletin (Impact Factor: 1.33). 04/1991; 25(5):559-565. DOI: 10.1007/BF00293514

ABSTRACT The content of total chlorine in o-cresol formaldehyde novolac epoxy resin (CNE), the main resin component for encapsulation
formulation, affects the reliability of semi-conductor device greatly and it is one of the major criteria used by the electronic
industry in measuring the quality of resins. A new process which synthesizes a high purity CNE with less than 300 ppm total
chlorine content has been developed. This high purity resin has provided an extended device life under the accelerated stress
test condition.

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