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.

Import Duty Rates by Country of Origin

Origin CountryMFN RateCh.99 SurchargesTotal Effective Rate
🇨🇳China5.5%+35.0%40.5%
🇲🇽Mexico5.5%+10.0%15.5%
🇨🇦Canada5.5%+10.0%15.5%
🇩🇪Germany5.5%+10.0%15.5%
🇯🇵Japan5.5%+10.0%15.5%

Alternative Classifications

This product could be classified differently depending on its characteristics or intended use.

2904.20.15.00Same rate: 40.5%

If contains both sulfo and carboxy groups (e.g., H-acid derivatives)

Derivatives with multiple functional groups classified by heading occurring last in numerical order.

2833.19.00.00Lower: 35% vs 40.5%

If imported as disodium salt form

Sodium sulfonic acid salts may fall to inorganic sulfonic acids if not classified with organic parent.

3824.99Lower: 15% vs 40.5%

If when supplied with stabilizers exceeding Chapter 29 note (f) allowances

Excess additives render it a chemical preparation rather than pure compound.

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Import Tips & Compliance

Request supplier Certificate of Analysis specifying <0.5% impurities to maintain Chapter 29 chemical compound status

Avoid retail packaging; bulk industrial shipments prevent shift to Chapter 32 retail dye provisions

Check REACH compliance documentation for EU-origin material destined for US transshipment