4-Mercaptobenzoic Acid from Mexico
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 — Mexico → United States
110%
Rate breakdown
9903.04.6095.8%Except as provided in heading 9903.04.61, patented pharmaceutical articles as provided for in subdivisions (c) and (d) of U.S. note 40 to this subchapter
9903.05.5510%Except for products described in headings 9903.05.85–9903.05.92 and 9903.05.94, articles the product of Mexico, as provided for in U.S. note 52 to this subchapter
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