| abstract |
The present invention relates to a polyimine precursor produced by thermal imidization, wherein the repeating unit represented by the following chemical formula (1) is composed of a repeating unit represented by the following chemical formula (2), and the following chemical formula (2) is repeated. The content of the unit is 30 mol% or more and 90 mol% or less with respect to all the repeating units, and 50 mol% or more of the total amount of B in the following chemical formula (1) and the following chemical formula (2) is a paraphenyl group and/or Or a specific divalent group containing two or more benzene rings. □ (wherein A is a tetravalent group obtained by removing a carboxyl group from a tetracarboxylic acid, and B is a divalent group obtained by removing an amine group from a diamine, but A and B contained in each repeating unit may be the same It may be different. X1 and X2 are each independently hydrogen, an alkyl group having 1 to 6 carbon atoms, or an alkylene group having 3 to 9 carbon atoms. |