1,8-Dihydroxynaphthalene-3,6-disulfonic acid (H Acid) from China

Pure 1,8-Dihydroxynaphthalene-3,6-disulfonic acid, known as H Acid, is a key intermediate for azo dye synthesis. This sulfonated phenol derivative falls under HTS 2908.99.0900 due to its specific chemical structure with only sulfo groups and its disodium salt form being explicitly named in the tariff.

Duty Rate — China → United States

40.5%

Rate breakdown

9903.03.0110%Except for products described in headings 9903.03.02–9903.03.11, articles the product of any country, as provided for in subdivision (aa) of U.S. note 2 to this subchapter
9903.88.0325%Except as provided in headings 9903.88.13, 9903.88.18, 9903.88.33, 9903.88.34, 9903.88.35, 9903.88.36, 9903.88.37, 9903.88.38, 9903.88.40, 9903.88.41, 9903.88.43, 9903.88.45, 9903.88.46, 9903.88.48, 9903.88.56, 9903.88.64, 9903.88.66, 9903.88.67, 9903.88.68, or 9903.88.69, articles the product of China, as provided for in U.S. note 20(e) to this subchapter and as provided for in the subheadings enumerated in U.S. note 20(f)

Import Tips

Provide detailed chemical analysis certificates confirming purity and structure match to avoid misclassification

Ensure SDS (Safety Data Sheets) comply with HAZMAT regulations for sulfonated organic acids

Verify import licenses for dye precursors if destined for textile or pigment manufacturing