2917.39.15.00 - Isophthalic acid

This HTS category encompasses **isophthalic acid**, a specific aromatic dicarboxylic acid. Isophthalic acid is characterized by its structure where the two carboxyl groups are attached to a benzene ring at the 1 and 3 positions. It serves as a vital intermediate in the production of various polymers, resins, and plasticizers.

While the sibling categories at this level cover other distinct aromatic polycarboxylic acid derivatives, such as trimellitic anhydride, phthalic acid, naphthalic anhydride, and specific halogenated or functionalized anhydrides, this subcategory is specifically reserved for isophthalic acid itself. The distinction lies in the precise chemical structure and the relative positions of the functional groups on the aromatic ring, which dictate their unique chemical properties and downstream applications.

As this node represents a leaf in the HTS structure, there are no further subcategories. Classification under 2917.39.15.00 is definitive for isophthalic acid. Importers and exporters should ensure that the substance being declared precisely matches the chemical identity of isophthalic acid, distinguishing it from isomers or other related carboxylic acids that fall under different tariff lines.