4-Mercaptobenzoic Acid from Canada
4-Mercaptobenzoic acid features para-substituted mercapto and carboxylic groups on benzene ring. HTS 2930.90.4920 classification as aromatic mercaptocarboxylic acid per Chapter 29 organo-sulfur provisions. Utilized in nanotechnology and self-assembled monolayers.
Duty Rate — Canada → United States
100%
Rate breakdown
9903.04.6095.8%Pharmaceuticals Annex IV: patented pharma articles — 100% floor rate
9903.05.900%Articles already subject to Section 232 (steel/aluminum/copper + derivatives, autos + parts, wood, medium/heavy vehicles + parts, semiconductors, patented pharma) — U.S. note 52(f)
Import Tips
• Require HPLC purity certificate >99%; CAS 107-91-5 for customs verification
• Static dissipative packaging required for nano-electronics grade material
• Avoid 2930.90.49.40 misclassification by confirming acid vs amide function