4,4'-Diamino-3-biphenylsulfonic Acid (3-Benzidinesulfonic Acid) from Japan
4,4'-Diamino-3-biphenylsulfonic acid is a sulfonated aromatic polyamine used as a dye intermediate. It is classified under tariff item 2921.59.00 as an 'other' aromatic polyamine, as sulfonic acid groups do not exclude it from this heading.
Duty Rate — Japan → Canada
0%
Import Tips
• Document the sulfonic acid substitution and purity level
• Ensure the product is a separate chemically defined compound
• Verify if the sulfonic acid group affects classification under other headings