Abstract: A method for the preparation of a diaminobisimide compound of the formula (I) substantially free of oligomers: ##STR1## wherein Ar.sup.1 is an optionally substituted aromatic residue which provides for good conjugation between the nitrogen containing groups; andAr is an optionally substituted aromatic residue characterized in that at least two molar proportions of an aromatic diamine of the formula (II)H.sub.2 N--Ar.sup.1 --NH.sub.2 (II)wherein Ar.sup.1 is as defined above,are heated with one molar proportion of an aromatic tetracarboxylic acid of the formula (III) or the corresponding dianhydride,(HOOC).sub.2 Ar(COOH).sub.2 (III)wherein Ar is as defined above,optionally in the presence of a polar solvent and optionally including 0.1 to 2 molar proportions of a tertiary amine.The compounds of formula (I) are useful curing agents in epoxy resin formulations.

Abstract: A method for the preparation of diaminobisimide compounds of the formula (I) which are substantially free of oligomers and are useful as curing agents in epoxy resin formulations: ##STR1## wherein Ar.sup.1 is an optionally substituted aromatic residue which provides for good conjugation between the nitrogen containing groups; and Ar is an optionally substituted aromatic residue, comprising heating an aromatic diamine of the formula H.sub.2 N--Ar.sup.1 --NH.sub.2, with an aromatic tetracarboxylic acid of the formula (HOOC).sub.2 (COOH).sub.2 or the corresponding dianhydride.