Naphthalene Trisulfonic Acid Trisodium Salt from Canada
1,3,6-Naphthalenetrisulfonic acid trisodium salt is a multi-sulfo derivative of naphthalene used in azo dye synthesis. Contains only sulfo groups, qualifying for HTS 2908.99.1500 as sulfonated phenol derivative.
Duty Rate — Canada → United States
15.5%
Rate breakdown
9903.03.0110%Except for products described in headings 9903.03.02–9903.03.11, articles the product of any country, as provided for in subdivision (aa) of U.S. note 2 to this subchapter
Import Tips
• HPLC purity >98% certification required; light-sensitive - opaque packaging
• Common issue: Dye coupling agents scrutinized for Chapter 32 colorant classification