Abstract: Thermosetting polycondensates containing amide and imide groups which are obtained by reacting 1,2,3,4-butanetetracarboxylic acid or its anhydride with one or more aliphatic, cycloaliphatic or aromatic diamines and one or more oxadicarboxylic acids or oxadicarboxylic acid esters of the general formulaROOC--CH.sub.2 --O--(CH.sub.2).sub.2 --O--.sub.n CH.sub.2 --COORwhere R is hydrogen or alkyl of 1 to 6 carbon atoms and n is 0 or an integer from 1 to 10, in a water-soluble organic solvent and/or water, at from 80.degree. to 200.degree. C. These polycondensates are useful as wire enamels, impregnating agents and adhesives.

Abstract: Pure halonaphthalic acid anhydrides are prepared from haloacenaphthenes by oxidation with nitric acid in a mixture of aliphatic carboxylic acid, water and nitric acid in the presence of vanadate, with or without further metal salts, at an elevated temperature and the reaction product is isolated and subjected to an oxidative after-treatment with hypochlorite in aqueous solution at a pH of from 9 to 12 at an elevated temperature. The products are intermediates for the manufacture of optical brighteners.