Several novel polyimide materials are disclosed. One example is a polyimide material comprising heterocyclic polyimide having an unit represented by the following general formula (1): ##STR00001## (wherein .PHI..sub.1s may be the same or different and are individually a quadrivalent organic group, the .PHI..sub.1s including at least 0.2 molar equivalent of a quadrivalent hetrocyclic group selected from the following Group (a), .PSI..sub.1s may be the same or different and are individually a bivalent organic group, and n is a positive integer).

 
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