2917.39.12.00 - 4,4'-(Hexafluoroisopropylidene)bis(phthalic anhydride)

This category encompasses aromatic polycarboxylic acids and their derivatives that are not specifically enumerated in the preceding subheadings. It serves as a residual category for such compounds. Specifically, HTS code 2917.39.12.00 pertains to the distinct chemical compound 4,4'-(Hexafluoroisopropylidene)bis(phthalic anhydride). This compound is characterized by its aromatic structure, the presence of two phthalic anhydride moieties linked by a hexafluoroisopropylidene group, distinguishing it by its specific chemical structure and the presence of fluorine atoms.

This classification differs from sibling categories such as 2917.39.04.00, which covers trimellitic anhydride and phthalic acid, and 2917.39.08.00 for naphthalic anhydride. Unlike these, 4,4'-(Hexafluoroisopropylidene)bis(phthalic anhydride) possesses a more complex bis-anhydride structure with a fluorinated linkage, rather than simpler anhydrides or acids. It is also distinct from 2917.39.15.00 (isophthalic acid) and 2917.39.17.00 (tetrabromophthalic anhydride) due to its unique chemical composition and the absence of bromine substituents.

As this is a leaf node, there are no further subcategories within 2917.39.12.00. Therefore, classification at this level relies entirely on the precise chemical identity and structure of the imported or exported substance matching the description "4,4'-(Hexafluoroisopropylidene)bis(phthalic anhydride)". Importers and exporters must ensure that laboratory analysis or product specifications definitively confirm the presence and structure of this specific compound to ensure accurate classification under this subheading.