4-Amino-5-Hydroxy-2,7-Naphthalenedisulfonic Acid (H Acid) from Mexico
H Acid is premier dye intermediate with amino-naphthalene core structure. HTS 2921.45.90 as 'other' naphthylamine derivative; multiple functions but amine principal. Widely used in reactive/direct dyes for cotton.
Duty Rate — Mexico → United States
16.5%
Rate breakdown
9903.05.5510%Except for products described in headings 9903.05.85–9903.05.92 and 9903.05.94, articles the product of Mexico, as provided for in U.S. note 52 to this subchapter
Import Tips
• CAS 90-64-2; sodium salt form CAS 5182-63-2 most common
• Light-sensitive; dark packaging mandatory
• 97% min purity standard; HPLC certificate required by dye manufacturers