Tobias Acid (2-Amino-1-naphthalenesulfonic acid)
Tobias acid is a chemically defined aromatic monoamine derivative with a sulfonic acid group, specifically 2-amino-1-naphthalenesulfonic acid. It falls under HTS 2921.45.90.10 as a derivative of 1-naphthylamine per Chapter 29 note (a). Primarily used as an intermediate in azo dye synthesis.
Import Duty Rates by Country of Origin
Alternative Classifications
This product could be classified differently depending on its characteristics or intended use.
If in salt form like Tobias acid sodium salt
Salts of aromatic monoamines classified with parent compound per Chapter 29 note on inorganic salts.
If pre-reacted into synthetic azo dye coupler
Completed synthetic organic coloring intermediates excluded from Chapter 29 by note 1(g).
If dissolved in water >20% for transport safety
Aqueous solutions may qualify as chemical preparations if solvent renders unsuitable for general use.
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Import Tips & Compliance
• Provide chemical purity certificates (typically 98%+ min) and CAS number (84-86-6) documentation to verify identity
• Ensure SDS includes GHS classification for skin/eye irritant hazards; REACH compliance required for EU transshipment
• Avoid misclassification as finished dye (HTS 32); confirm no azo coupling has occurred
Related Products under HTS 2921.45.90.10
Tobias Acid with 0.2% Stabilizer
Tobias acid containing 0.2% sodium sulfite stabilizer for transport stability. Remains classified under HTS 2921.45.90.10 per Chapter 29 note 1(f) as stabilizer necessary for preservation. Used in disperse dye manufacturing.
Pharma Grade Tobias Acid USP
Ultra-pure pharmaceutical grade Tobias acid meeting USP standards for API synthesis. Classified as chemically defined compound under HTS 2921.45.90.10 despite high purity. Trace impurities <50 ppm heavy metals.
Tobias Acid 50% Aqueous Solution
50% aqueous solution of Tobias acid for safe transport, classified under HTS 2921.45.90.10 per Chapter 29 note 1(d). Solution concentration prevents crystallization during shipping. Used directly in coupling baths.
Dye Intermediate Tobias Acid Flake
Flaked Tobias acid for rapid dissolution in dye manufacturing. Chemically defined aromatic sulfonic acid classified HTS 2921.45.90.10. Anti-caking agent <0.1% permitted.
High Assay Tobias Acid 99.5%
Premium 99.5% assay Tobias acid for direct black dye synthesis. Meets Chapter 29 criteria as separate chemically defined compound under HTS 2921.45.90.10. Low isomer content <0.1%.
Technical Grade Tobias Acid 99%
High-purity technical grade Tobias acid (99% min) used in industrial dye manufacturing. Classified under HTS 2921.45.90.10 as a separate chemically defined aromatic amine-sulfonic acid derivative. Supplied as off-white powder with standardized assay.