Aluminum foil is a critical material in pharmaceutical packaging due to its superior barrier properties against moisture, oxygen, light, and contaminants, which protect medicine efficacy and ensure a long shelf life. It is non-toxic, safe for direct contact with medications, and easily formable into various packaging types
Key Properties and Benefits
The unique characteristics of aluminum foil make it an ideal choice for the stringent requirements of pharmaceutical packaging:
- Exceptional Barrier Protection: Aluminum foil is virtually impermeable to moisture, gases (including oxygen), light, and microorganisms. This complete barrier is crucial for protecting sensitive drug formulations from degradation and maintaining their potency.
- Hygiene and Safety: The material is non-toxic, odorless, and stable, meaning it does not react with or contaminate the pharmaceutical products it contains. The high temperatures used during its annealing and final processing also ensure the foil is in a sterile condition when produced.
- Formability and Deadfold: Aluminum is highly malleable, which allows it to be formed into various shapes (like blister cavities) without cracking. Its “deadfold” characteristic (it stays folded or shaped after pressure is applied) is especially useful in collapsible tubes, preventing air and contaminants from being drawn back into the tube after squeezing.
- Tamper Evidence and Security: Foil-based packaging clearly indicates if a product has been opened or tampered with, enhancing product safety. Anti-counterfeiting measures like holographic effects can also be integrated into the foil surface.
- Lightweight and Recyclable: The material is lightweight, reducing transportation costs, and is 100% recyclable, which aligns with modern sustainability efforts in the industry.
Common Pharmaceutical Applications
| Blister Packs (點對點) | The most common form of packaging for tablets and capsules, featuring a plastic tray sealed with a push-through aluminum foil lid. Hard temper foil is typically used for easy push-through access. | 0.02 – 0.03 mm thick; Alloy 8011-H18 |
| Cold Form Foil (Alu-Alu) | A premium, highly protective option where both the lidding and the formed cavity are made of a multi-layer aluminum laminate (typically OPA/Alu/PVC). This provides the highest barrier performance for highly sensitive drugs. | 0.045 – 0.065 mm thick; Alloy 8021-O or 8079-O |
| Strip Packs | Medications are sealed between two layers of soft aluminum foil or foil laminates. These offer high barrier performance and are typically easy to tear open. | 0.02 – 0.05 mm thick; 合金 8011, 8079 (soft temper) |
| Sachets and Pouches | Laminated aluminum foil pouches used for powders, creams, liquids, and sterile fluids. They are robust and ensure contents remain in peak condition over long periods. | Varies based on multi-layer laminate structure |
