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Thioxanthene-9-one (Thioxanthone) from Canada

Thioxanthene-9-one, commonly called thioxanthone, is a tricyclic aromatic heterocyclic ketone with a central sulfur atom. It is specifically enumerated under HTS 2934.99.05.00 as an 'aromatic heterocyclic compound.' Widely used as a photoinitiator in UV-curable inks, coatings, and adhesives.

Duty Rate — Canada → United States

15.8%

Rate breakdown

9903.05.2910%Section 301 (forced labor) — additional 10% ad valorem on products of Canada

Import Tips

Include UV absorption spectrum data confirming photoinitiator properties while maintaining chemical classification

Light-protected packaging essential to prevent premature activation during transit

Specify 'technical grade >98% purity' on invoices to distinguish from formulated ink preparations