8-Amino-1-naphthol-5-sulfonic acid (Schaeffer's acid) from China
Schaeffer's acid is explicitly named in HTS 2922.21.1000 and functions as a dye intermediate for acid wool dyes and reactive dyes. Its sulfonic acid group enhances water solubility while maintaining coupling reactivity. Commonly imported at 96% minimum assay.
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
• Isomer-specific NMR spectrum confirms identity versus gamma acid or other isomers
• Anti-caking agent declaration required if >1% added (permitted by chapter note 1(f))
• Temperature-controlled shipping prevents degradation above 40°C