Homophthalic acid (also known as 2-carboxybenzene-1,3-dicarboxylic acid) is a chemical compound with the molecular formula C8H6O4. It is a benzene derivative containing two carboxyl groups (-COOH) attached at the 1 and 3 positions of the benzene ring. This compound can be used in a variety of industrial applications, especially in polymer synthesis and chemical processes. https://www.sarex.com/fine/product/key-products/homophthalic-acid-stellar-2001