Boric Acid and Sodium Tetraborate Hardening Agent from Mexico
Dry blend of boric acid and sodium tetraborate (borax) used as a chemical hardener for inorganic foundry binders to accelerate setting time and improve mold strength. Classified in HTS 3824.99.39.90 for multi-inorganic compound preparations. Essential for no-bake foundry systems requiring rapid mold production.
Duty Rate — Mexico → United States
10%
Rate breakdown
9903.05.5510%Section 301 (forced labor) — additional 10% ad valorem on products of Mexico
Import Tips
• Include boron content analysis for DOT hazardous material shipping; verify compatibility with specific silicate binders; maintain dry storage conditions to prevent premature reaction