Trimellitic anhydride is an organic compound with the formula HO2CC6H3(C2O3).

It is the cyclic anhydride of trimellitic acid.

The compound is a colorless to white solid.

It's primarily used in the production of various polymers, polyesters, agricultural chemicals and dyes.

Several thousand tons of this compound are produced annually as a precursor to plasticizers for polyvinyl chloride.