Thermally stable anthrapyridone compositions

An anthrapyridone composition of the formula: is disclosed, where "A" and "B" are independently selected from substituted or unsubstituted cyclic ketone groups having from about 10 to about 20 ring carbon atoms; "a" is an integer having a value from 0-4, R1-R4 are monovalent substituents; with the proviso that when "a" is 0, R1 is selected from the group consisting of a hydrogen, an alkyl group, a secondary amino group and an aminosulphonyl group; and R2-R4 are substituents selected form the group consisting of a hydroxyl group, an aliphatic group, an aromatic group, a heterocyclic group, a halogen atom, a cyano group, a carbonyl containing group, an amino group and a sulphonyl-containing group. The anthrapyridones are useful as thermally stable colorants for producing colored polymer resins and articles that require high temperature polymer processing conditions.