Aluminium Foil Laminates for Medical & Pharma Packaging
Aluminium Foil Laminates for Medical & Pharma Packaging
Near-absolute barrier against oxygen, moisture, and light — protecting moisture-sensitive drugs and implants with validated foil laminate structures.
Aluminium Foil as a Packaging Barrier
Aluminium foil provides near-zero permeability to oxygen, water vapour, light, and aromas — a barrier level unachievable by polymer films alone. In medical and pharmaceutical packaging, foil laminates are the material of choice for moisture-sensitive drugs (ICH stability Class IV–V), implantable devices, moisture-sensitive diagnostics, and sterile products requiring extended shelf life under ambient conditions.
Foil thickness in packaging laminates ranges from 6 to 20 µm. Pinholes increase significantly below 6 µm; above 20 µm, formability and cost become limiting factors. 9 µm and 12 µm are the most common pharmaceutical grades, balancing barrier with cold-forming capability.
Alu-Alu Cold-Form Blister (CFF)
Cold-formed foil (CFF) blister uses an OPA/foil/PVC or OPA/foil/PE laminate that is mechanically formed at room temperature into cavities — unlike PVC/PVDC thermoforming which uses heat. Cold forming creates cavities with near-vertical walls and a matte, non-reflective surface.
Advantages of CFF
Near-zero WVTR (<0.1 g/m²/day) and OTR (<0.05 cc/m²/day) — up to 100× better moisture barrier than PVDC. Essential for highly hygroscopic APIs, effervescent tablets, and moisture-sensitive biologics. Enables ambient shelf life of 24–60 months for products that would otherwise require refrigeration.
Limitations
Lower production speeds than thermoform lines (typically 200–400 blister/min vs. 600–1200 for PVC). Cavities are less uniform in depth due to material springback. Alu-alu is not transparent — product inspection requires manual or camera-based systems specifically calibrated for opaque blisters.
| Laminate | Total Gauge (µm) | WVTR (g/m²/day) | Application |
|---|---|---|---|
| OPA 25/Foil 45/PVC 60 | 130 | <0.1 | Hygroscopic tablets, capsules |
| OPA 25/Foil 60/PVC 60 | 145 | <0.05 | Effervescent, biologic drugs |
| OPA 25/Foil 45/PE 50 | 120 | <0.1 | Child-resistant, EO sterilisation |
Foil Lidding for Medical Pouches and Trays
PET/foil/PE and PET/foil/sealant laminates are used as lidding films on rigid trays and as the forming or lidding component of peel pouches for moisture-sensitive implants, IVD reagents, and active pharmaceutical devices. The foil layer provides light and moisture barrier while the PET outer layer provides stiffness, printability, and puncture resistance.
Regulatory Compliance
Aluminium foil packaging materials for pharmaceutical use must comply with Ph.Eur. 3.2.1 (containers for pharmaceutical preparations), 21 CFR 177 (FDA indirect food additive), and ICH Q3D (elemental impurities) where applicable. For medical devices, materials must be documented in the technical file as per EU MDR Annex I essential requirements — including biocompatibility data per ISO 10993-1 if there is direct or indirect patient contact.
Frequently Asked Questions
When should I use alu-alu vs. PVC/PVDC blisters?
Choose alu-alu (CFF) when the API has a water activity specification requiring WVTR below 0.5 g/m²/day — typically hygroscopic, effervescent, or moisture-degrading drugs. PVC/PVDC (0.5–2 g/m²/day WVTR) is adequate for most solid oral dosage forms that are not moisture-sensitive and offers higher line speeds and lower material cost. PVC-only (20–30 g/m²/day) is suitable only for tablets with no moisture sensitivity concern.
Does aluminium foil affect MRI compatibility?
Aluminium is non-ferromagnetic and does not cause MRI artefacts. However, foil is conductive and can cause eddy currents and heating in strong RF fields. Medical device packaging using foil laminates must be removed before patient MRI procedures — this should be specified in device labelling. For devices used in MRI environments, consider SiOx-coated films as MRI-compatible alternatives with near-foil oxygen barrier.
What are the pinhole limits for pharmaceutical foil?
Ph.Eur. and ISO standards do not specify absolute pinhole limits for foil packaging — validation is performance-based. As a guideline, 9 µm foil typically has 0–2 pinholes/m²; 6 µm foil has 5–15/m². Pinholes >50 µm significantly degrade barrier. Pinhole count should be included in foil CoA requirements and verified during initial material qualification.