H Acid Coupling Component from Canada
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 — Canada → United States
16.5%
Rate breakdown
9903.05.2910%Section 301 (forced labor) — additional 10% ad valorem on products of Canada
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