4-Amino-1-naphthalenesulfonic acid, sodium salt (Naphthionic acid sodium salt) from China
Naphthionic acid sodium salt, chemically 4-amino-1-naphthalenesulfonic acid sodium salt, serves as a diazo component in dye chemistry. It matches HTS 2921.45.20.00 explicitly as a named aromatic monoamine derivative and salt thereof. Supplied as a soluble powder for coupling reactions in pigment production.
Duty Rate — China → United States
40.8%
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
9903.88.0325%Except as provided in headings 9903.88.13, 9903.88.18, 9903.88.33, 9903.88.34, 9903.88.35, 9903.88.36, 9903.88.37, 9903.88.38, 9903.88.40, 9903.88.41, 9903.88.43, 9903.88.45, 9903.88.46, 9903.88.48, 9903.88.56, 9903.88.64, 9903.88.66, 9903.88.67, 9903.88.68, or 9903.88.69, articles the product of China, as provided for in U.S. note 20(e) to this subchapter and as provided for in the subheadings enumerated in U.S. note 20(f)
Import Tips
• Certify sodium salt form with ionic content analysis; free acid form might classify differently under amine headings
• Declare as 'not for retail sale' to prevent shift to Chapter 32 exclusions for coloring matter preparations
• Monitor purity thresholds; impurities over 5% may trigger mixture classification under heading 3824