4-Amino-2-stilbenesulfonic acid from China
4-Amino-2-stilbenesulfonic acid is a specific aromatic amine derivative with a sulfonic acid group, explicitly listed under HTS 2921.49.10.00. It is primarily used as an intermediate in the production of optical brightening agents for textiles, paper, and detergents. This chemically defined compound falls within Chapter 29 for separate organic compounds with amine-function groups.
Duty Rate — China → United States
43.3%
Rate breakdown
9903.05.3112.5%Except for products described in headings 9903.05.85–9903.05.92, articles the product of China, as provided for in U.S. note 52 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
• Verify purity certificate (≥98%) and provide chemical analysis to confirm identity as listed in HTS 2921.49.10.00
• Include Safety Data Sheet (SDS) and ensure packaging complies with DOT/UN regulations for hazardous chemicals
• Avoid misclassification as dye intermediates under Chapter 32; request binding ruling for custom formulations