4-Amino-5-hydroxynaphthalene-2,7-disulfonic Acid (H Acid)
H acid is a multi-substituted 1-naphthylamine derivative essential for direct and reactive dyes in cotton dyeing. Classified in HTS 2921.45.90.90 as 'other' α-naphthylamine derivative, the amine group defines its place despite phenolic and sulfonic functions. Chapter 29 classification rules ensure amine-function precedence.
Import Duty Rates by Country of Origin
Alternative Classifications
This product could be classified differently depending on its characteristics or intended use.
If imported as amino-alcohol derivative emphasizing hydroxy function
Alcohol amines class in 2922 if oxygen function characteristics dominate.
If when pre-coupled with diazonium salts for dye production
Partial dye synthesis moves to synthetic coloring matter in Chapter 32.
If for sugar esters/esthers if chemically derived that way
Later subchapter provisions supersede per Chapter note on numerical order.
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Import Tips & Compliance
• Include chromatograms showing >95% purity; multi-functional nature invites classification challenges
• Declare as 'amine-function compound' explicitly on commercial invoice with structure diagram
• For EU-sourced material, verify REACH compliance as it affects US import documentation
Related Products under HTS 2921.45.90.90
4-Amino-1-naphthalenesulfonic Acid
4-Amino-1-naphthalenesulfonic acid is a derivative of 1-naphthylamine with a sulfonic acid group, used primarily as an intermediate in dye manufacturing. It falls under HTS 2921.45.90.90 as a derivative of 1-naphthylamine (α-naphthylamine) that is not specifically listed elsewhere in the subheading. This aromatic monoamine derivative contains the characteristic amine-function group directly linked to the naphthalene ring.
1-Naphthylamine-4,8-disulfonic Acid
This disulfonic acid derivative of 1-naphthylamine serves as a key intermediate for acid dyes and azoic coupling components. Classified under HTS 2921.45.90.90 as an 'other' derivative of α-naphthylamine, it retains the primary aromatic amine function despite sulfonic substitutions. The classification follows Chapter 29 rules prioritizing amine-function compounds.
7-Amino-1-hydroxynaphthalene-3-sulfonic Acid
Also known as J acid, this naphthylamine derivative with hydroxy and sulfonic groups is crucial for synthesizing reactive and direct dyes. It qualifies for HTS 2921.45.90.90 as an 'other' derivative of 1-naphthylamine per Chapter 29 amine-function priority. The molecule's primary aromatic amine defines its tariff classification.
1-Naphthylamine-8-sulfonic Acid (Peri Acid)
Peri acid is a monosulfonic derivative of 1-naphthylamine used in azo dye production for textiles. It falls under HTS 2921.45.90.90 as an unspecified derivative of α-naphthylamine, maintaining classification in the amine-function heading. The sulfonic acid enhances water solubility without altering the core amine classification.
2-Naphthylamine-6-sulfonic Acid (Laurent's Acid)
Laurent's acid, a derivative of 2-naphthylamine (β-naphthylamine), is used in acid dye synthesis. It is classified under HTS 2921.45.90.90 as an 'other' derivative within the naphthylamine subheading. The aromatic amine-function remains the principal characteristic for tariff purposes.
1-(Phenylamino)naphthalin-8-sulfonic Acid (Naphthol AS)
Naphthol AS is a substituted naphthylamine derivative used as a dye coupler in pigment printing. It falls under HTS 2921.45.90.90 as an 'other' derivative featuring the naphthylamine core with phenylamino substitution. The classification adheres to Chapter 29's amine-function provisions.