2918.29.22.00 - p-Hydroxybenzoic acid

This HTS classification, 2918.29.22.00, specifically designates p-Hydroxybenzoic acid. This compound is a phenolic carboxylic acid, characterized by a hydroxyl group attached to the benzene ring at the para position relative to the carboxyl group. It serves as a crucial intermediate in the synthesis of various compounds, including parabens, which are widely used as preservatives.

Within the broader category of "Carboxylic acids with phenol function but without other oxygen function, their anhydrides, halides, peroxides, peroxyacids and their derivatives: Other," this sub-heading distinguishes p-Hydroxybenzoic acid from its isomers and related naphthoic acids found in sibling categories. For instance, sibling categories include m-Hydroxybenzoic acid (2918.29.08.00), which has the hydroxyl group in the meta position, and various naphthoic acid derivatives, which are based on a naphthalene ring system rather than a benzene ring. The classification here hinges on the specific positional isomer of the hydroxybenzoic acid and its absence of other oxygen-containing functional groups beyond the carboxylic acid and phenol functionalities.

As this is a leaf node, there are no further subcategories. The precise chemical structure and positional arrangement of the hydroxyl and carboxyl groups are the definitive criteria for classification under 2918.29.22.00, ensuring accurate tariff application for this specific organic compound.