H Acid Coupling Component from China
H Acid (1-amino-8-naphthol-3,6-disulfonic acid) serves as an azo coupling agent for substantive dyes on cotton. Though primarily phenolic, its role in azo dye synthesis links it to products in additional U.S. note 3 under HTS 2927.00.40.00. This chemically defined compound is essential for dye chemistry per chapter scope.
Duty Rate — China → United States
44%
Rate breakdown
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)
9903.05.3112.5%Section 301 (forced labor) — additional 12.5% ad valorem on products of China
Import Tips
• Ensure documentation specifies use in diazo coupling to justify note 3 classification over general aromatics
• Test for heavy metal impurities; sulfonated compounds often require REACH-like compliance data
• Ship in stabilized aqueous solution only if per chapter note (d) for water-dissolved products