Bayer's Acid Salt (1-Naphthylamine-4-sulfonic Acid Sodium Salt)
Bayer's acid sodium salt serves as a crucial intermediate for direct and reactive dyes, featuring the aminohydroxynaphthalenesulfonic acid structure. It is specifically listed under HTS 2922.21.4000 per additional U.S. note 3 to section VI for quota-controlled dye chemicals. The compound's classification follows chapter rules prioritizing oxygen-function amino-phenols.
Import Duty Rates by Country of Origin
Alternative Classifications
This product could be classified differently depending on its characteristics or intended use.
If containing more than one type of oxygen function (e.g., additional keto group)
Chapter notes exclude multi-oxygen function compounds from 2922.21; they fall under 'other' amino-phenols in 2922.29.
If for retail-packaged or finished pigment forms
Synthetic organic pigments and preparations go to chapter 32 per exclusion note (g).
If diluted beyond standard strengths for azo dye production
Chapter note (h) specifies standard dilutions stay in 29; others become preparations.
Not sure which classification is right?
The Tariff Assistant works through the GRI rules on your specific product to reach the right HTS code — and can price the duty on it in the same conversation.
Import Tips & Compliance
• Cross-reference exact chemical name against U.S. note 3 list to confirm tariff line applicability before shipment
• Maintain batch records showing synthesis from qualifying naphthol precursors to support chapter 29 chemical definition
• Beware of misdeclaration as 'dye intermediate mixture' which could trigger 3824 classification and different duties
Related Products under HTS 2922.21.40.00
Schaeffer's Salt (2-Naphthylamine-6-sulfonic Acid)
Schaeffer's salt is a sodium salt of 2-naphthylamine-6-sulfonic acid, a key aminohydroxynaphthalenesulfonic acid derivative used primarily as an intermediate in azo dye synthesis. It falls under HTS 2922.21.4000 as a product described in additional U.S. note 3 to section VI, which covers specific organic compounds subject to quota restrictions for dye production. The compound features both amino and sulfonic acid oxygen functions on a naphthalene ring.
Tobias Acid (2-Naphthylamine-8-sulfonic Acid)
Tobias acid is the sodium salt of 2-naphthylamine-8-sulfonic acid, widely used as a diazo component in manufacturing acid dyes and pigments. Classified under HTS 2922.21.4000 due to its status in additional U.S. note 3 to section VI, restricting imports for dye production. It qualifies as an oxygen-function amino-compound with amino, hydroxy, and sulfonic groups.
Neville-Winter Acid (1-Naphthylamine-5-sulfonic Acid)
Neville-Winter acid is an aminohydroxynaphthalenesulfonic acid used in acid dye manufacturing, subject to HTS 2922.21.4000 quotas under U.S. note 3 to section VI. Its structure with amino group ortho/para to sulfonic acid enables diazotization for azo coupling. Classification adheres to chapter priority for oxygen-function amino-naphthols.
Laurent's Acid (2-Naphthylamine-3,6-disulfonic Acid)
Laurent's acid, a di-sulfonic derivative of 2-naphthylamine, functions as a dye coupler in textile coloration chemistry. Covered by HTS 2922.21.4000 as specified in additional U.S. note 3 for import quotas. Despite two sulfonic groups, it remains classified here due to primary amino-hydroxy-naphthalene structure.
K-acid (4-Amino-5-hydroxynaphthalene-2,7-disulfonic Acid)
K-acid serves as an important coupling component for substantive dyes due to its multiple sulfonic groups enhancing water solubility. HTS 2922.21.4000 applies per U.S. note 3 listing for quota purposes. The compound exemplifies oxygen-function amino-naphthols with salt-forming capability.