Imide-modified polyester resin and wire enamel containing the imide- modified polyester resin

摘要

An imide-ring containing polyester comprising the reaction product ofPP(A) (1) a dicarboxylic acid of the formula ##EQU1## wherein R.sub.1 represents a divalent organic group, R.sub.2 represents a trivalent organic group, and n≧1, the dicarboxylic acid of the formula (I) comprising the reaction product of 1 mole of an imide compound having terminal amino groups of the formula (II) ##EQU2## wherein R.sub.1 has the same meaning as above, or of an imide precursor thereof, with 2 moles of a tricarboxylic acid anhydride of the formula (III) ##EQU3## wherein R.sub.2 has the same meaning as above, the imide compound of the formula (II) being prepared by reacting n moles of 1,2,3, 4-butanetetracarboxylic acid (hereinafter referred to as BTC) with (n+1) moles of a diamine of the formula (IV) ##EQU4## wherein R.sub.1 has the same meaning as above; or (A) (2) a mixture of the dicarboxylic acid of the formula (I) with at least one other polycarboxylic acid (including the lower alkyl ester thereof) withPP(B) at least one polyhydric alcohol; and a wire enamel containing the imide ring containing polyester described above.