1,3,6-1,3,7-NTS Acid for Acid Dyes
Mixture of naphthalenetrisulfonic acid isomers (1,3,6 & 1,3,7) used as diazo component in acid dye synthesis. Precisely matches HTS 2904.10.15.00 for mixtures of these specific sulfonated derivatives containing only sulfo groups.
Import Duty Rates by Country of Origin
Alternative Classifications
This product could be classified differently depending on its characteristics or intended use.
If for other naphthalenetrisulfonic acid isomer mixtures not specified
2904.10.15.00 specifically names this isomer pair; others go to basket provision.
If put up in forms particularly suitable for retail dye use
Chapter 29(g) exclusion sends retail-ready coloring forms to Chapter 32.
If misidentified as ketonitrilosulfonates or similar derivatives
Different oxygen/nitrogen functions change classification within Chapter 29 headings.
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
• Document intended industrial use to distinguish from Chapter 32 exclusions for coloring matters
• Test for heavy metal impurities (<10 ppm) required for dye intermediate import clearance
• Use DOT-approved corrosive packaging; common violation leads to CBP holds
Related Products under HTS 2904.10.15.00
Naphthyltrisulfonic Acid Mixture (1,3,6 & 1,3,7 Isomers)
This is a specific mixture of 1,3,6-naphthalenetrisulfonic acid and 1,3,7-naphthalenetrisulfonic acid isomers, classified under HTS 2904.10.15.00 as sulfonated derivatives of hydrocarbons containing only sulfo groups. It serves as a key intermediate in azo dye manufacturing, meeting Chapter 29 note (a) for separate chemically defined organic compounds.
Dye Coupling Grade Naphthalenetrisulfonic Acid Isomer Mix
Specialty isomer mixture (1,3,6- and 1,3,7-naphthalenetrisulfonic acids) optimized for diazo coupling in azo pigment production. HTS 2904.10.15.00 applies as chemically defined sulfonated naphthalene derivative per Chapter 29 exclusions from dyes.
1,3,6/1,3,7-Naphthalenetrisulfonic Acid Technical Grade
Technical grade mixture of 1,3,6- and 1,3,7-naphthalenetrisulfonic acid used in industrial dye synthesis. Falls under HTS 2904.10.15.00 per Chapter 29 scope for sulfonated hydrocarbon derivatives with only sulfo groups, excluding coloring matters of Chapter 32.
Industrial Naphthalene-1,3,6,7-Trisulfonic Acid Blend
Industrial-grade 50/50 blend of 1,3,6- and 1,3,7-naphthalenetrisulfonic acids for synthetic dye production. Classifies under HTS 2904.10.15.00 as the explicitly named mixture of these sulfonated hydrocarbon derivatives.