2902.90.60.00 - Biphenyl (Diphenyl), in flakes

This HTS classification, 2902.90.60.00, specifically covers biphenyl, also known as diphenyl, when presented in a flaked form. Biphenyl is an aromatic hydrocarbon characterized by two phenyl rings directly bonded. Its application often lies in its use as a heat transfer medium, a starting material for certain organic synthesis processes, or as a component in flame retardants and dyes. The "in flakes" designation is a crucial physical characteristic for classification under this specific subheading, differentiating it from other forms such as liquid or crystalline.

Within the broader category of "Cyclic hydrocarbons: Other," this subheading is distinct from its siblings. For instance, subheadings like 2902.90.10.00 and 2902.90.20.00 cover specific named polycyclic aromatic hydrocarbons and other complex aromatic compounds, while 2902.90.30 addresses alkylbenzenes and polyalkylbenzenes which involve alkyl chains attached to benzene rings. The presence of 2902.90.40.00 for anthracene and a specific styrene derivative, and the catch-all 2902.90.90.00 for other cyclic hydrocarbons not otherwise specified, further delineate the scope. Therefore, biphenyl in flake form is a precisely defined entity within this hierarchical structure.

As this is a leaf node within the HTS database, there are no further subcategories or subdivisions under 2902.90.60.00. This means that any biphenyl presented in flake form will be classified directly under this code, provided it meets the chemical description of biphenyl. The classification relies on the accurate identification of the substance as biphenyl and confirmation of its physical state as flakes.