Abstract: The products of the invention are high melting, highly insoluble N,N'-bis(arylazo)diimides prepared by reacting 2 mols of an arylazoaromatic amine with pyromellitic acid dianhydride or 3,3',4,4'-benzophenone tetracarboxylic acid dianhydride. The products are colored and useful as pigments in surface coating compositions and plastics.

Abstract: Bis-quinizarin compounds are disclosed. They have the structure: ##STR1## where X is ##STR2## --CF.sub.2 --, or a bond.

Abstract: Acetylene end-capped polyimide oligomers are prepared by a process including the following sequential steps:1. Preparing an alkanol or ether solution containing substantially 1 molar equivalent of a dialkyl ester of an aromatic tetracarboxylic acid,2. Adding substantially 0.5 to 0.8 molar equivalent of an aromatic diamine to the solution of (1) to form a reaction product between the diacid and the diamine,3. Adding an aminoarylacetylene to the solution of (2) in a quantity sufficient to provide amine groups equivalent to the free carboxylic acid groups present in the product of (2).4. Heating the solution of (3) to vaporize the solvent therefrom, and5. Heating the product of (4) to convert the carboxylic acid groups, the ester groups, and the amino groups thereof to imide groups.The temperature in steps (2) and (3) is maintained below about 50.degree. C. The temperature in steps (4) and (5) is maintained below about 210.degree. C.