4-Hydroxy-1-naphthalenesulfonic acid, 98% purity
High-purity technical grade 1-Naphthol-4-sulfonic acid for pharmaceutical and dye intermediates. Qualifies under HTS 2908.99.06.00 as a separate chemically defined compound with only sulfo groups, per Chapter 29 scope.
Import Duty Rates by Country of Origin
Alternative Classifications
This product could be classified differently depending on its characteristics or intended use.
If purity below threshold with significant impurities
Impure preparations become chemical mixtures under Chapter 38, not pure Chapter 29 compounds.
If oxidized form lacking sulfo definition
Quinone derivatives without sulfo groups classify under 2914 oxygen-function headings.
If pre-reacted into pigment dispersion
Processed into coloring matter, moving to Chapter 32 dyes.
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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
• Provide CoA with purity >95% to affirm 'chemically defined' status
• Segregate from impurities that could invoke Chapter 38 mixtures
• Comply with TSCA registration for US import
Related Products under HTS 2908.99.06.00
1-Naphthol-4-sulfonic acid
1-Naphthol-4-sulfonic acid is a sulfonated derivative of 1-naphthol, featuring a sulfo group at the 4-position on the naphthalene ring. It falls under HTS 2908.99.06.00 as a chemically defined organic compound containing only sulfo groups, classified among halogenated, sulfonated derivatives of phenols or phenol-alcohols.
Sodium 1-Naphthol-4-sulfonate
The sodium salt of 4-Hydroxy-1-naphthalenesulfonic acid, used in azo dye coupling reactions. Classified under HTS 2908.99.06.00 per Chapter 29 note 5(C)(1), as inorganic salts of organic sulfo-function compounds are placed with the parent acid.
Potassium 1-Naphthol-4-sulfonate
Potassium salt form of 1-Naphthol-4-sulfonic acid, soluble for use in textile dye manufacturing. Fits HTS 2908.99.06.00 as a salt of a sulfo-group derivative of phenol-alcohols, following Chapter 29 salt classification rules.
1-Naphthol-4-sulfonic acid monohydrate
Hydrated form of 1-Naphthol-4-sulfonic acid, stable for transport in dye production. Remains under HTS 2908.99.06.00 as water-associated product of (d) note, not altering chemical classification.
Ammonium 1-Naphthol-4-sulfonate
Ammonium salt of 4-Hydroxy-1-naphthalenesulfonic acid, used in analytical chemistry. Classified in HTS 2908.99.06.00 following Chapter 29 rule for salts of sulfo derivatives.