H Acid Monosodium Salt (4-Amino-5-hydroxy-2,7-naphthalenedisulfonic acid, monosodium salt)
H Acid monosodium salt is a key dye intermediate specifically enumerated under HTS 2922.21.1000 for use in manufacturing direct, reactive, and acid dyes. This salt form improves solubility and handling compared to the free acid. It contains both amino and hydroxy functions with naphthalene sulfonic acid structure as defined in chapter notes.
Import Duty Rates by Country of Origin
Alternative Classifications
This product could be classified differently depending on its characteristics or intended use.
If for salts of different amino-naphthol sulfonic acids not specifically enumerated
Chapter notes require classification with the organic base occurring last in numerical order, potentially shifting to 2921
If considered primarily as sulfonic acid salts rather than organic base
Inorganic sulfonic acid salts classify in Chapter 28, though chapter 29 organic compound takes precedence
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Import Tips & Compliance
• Provide sodium content analysis to confirm salt form versus free acid classification
• Declare as UN 3265 if solution exceeds 10% concentration; dry powder typically UN 3077
• Avoid retail packaging that might trigger Chapter 32 classification for dye preparations
Related Products under HTS 2922.21.10.00
Chicago Acid (4-Amino-5-hydroxy-1,3-naphthalenedisulfonic acid)
Chicago Acid is a specific aminohydroxynaphthalenedisulfonic acid used primarily as an intermediate in the synthesis of reactive dyes and azo pigments. It falls under HTS 2922.21.1000 as one of the enumerated oxygen-function amino-naphthol sulfonic acids containing both amino and hydroxy groups with sulfonic acid functions. This chemically defined organic compound is supplied as a powder or solution for industrial dye production.
1-Amino-8-hydroxy-3,6-naphthalenedisulfonic acid
This specific diaminohydroxynaphthalenedisulfonic acid is explicitly listed in HTS 2922.21.1000 and serves as a diazo coupling component in acid dye synthesis. Its structure features both amino (-NH2) and hydroxy (-OH) oxygen functions on the naphthalene ring with sulfonic acid groups. Supplied as technical grade powder (95%+ purity) for chemical manufacturing.
6-Amino-1-naphthol-3-sulfonic acid (J Acid)
J Acid (6-Amino-1-naphthol-3-sulfonic acid) and its salts are specifically enumerated under HTS 2922.21.1000 as essential intermediates for direct and reactive dyes used in cellulosic fibers. The compound's ortho amino-hydroxy positioning enables stable azo coupling. Typically imported as 92-98% purity technical grade.
8-Amino-1-naphthol-5-sulfonic acid (Schaeffer's acid)
Schaeffer's acid is explicitly named in HTS 2922.21.1000 and functions as a dye intermediate for acid wool dyes and reactive dyes. Its sulfonic acid group enhances water solubility while maintaining coupling reactivity. Commonly imported at 96% minimum assay.
H Acid Monopotassium Salt
The monopotassium salt of 4-Amino-5-hydroxy-2,7-naphthalenedisulfonic acid (H acid) is specifically listed in HTS 2922.21.1000. This salt form offers different solubility characteristics than sodium salt for specific dye applications. Classifies as organic salt of enumerated base per chapter note 3(C).
Chicago Acid Sodium Salt
Sodium salt of 4-Amino-5-hydroxy-1,3-naphthalenedisulfonic acid (Chicago acid) specifically enumerated in HTS 2922.21.1000. Widely used in reactive dye synthesis for cotton. The salt formation follows chapter note 3(C)(1) classification with parent acid.