Blister foil, also known as PTP fojl tal-aluminju (Press Through Package Aluminum Foil) or aluminum-plastic blister packaging material in the field of pharmaceutical packaging, is a major form of pharmaceutical packaging.

Blister foil is mainly made of electrolytic aluminum calendering, with good ductility and uniform thinness, usually less than 0.2mm thick. It is mainly used for heat sealing with transparent plastic hard sheets (such as PVC, PVDC-coated PVC, PP, eċċ.) to form blister packaging.

The raw material manufacturing of blister foil generally uses aluminum foil alloy. The aluminum alloy used for medical blister foil is specially selected to protect the encapsulated drugs from external factors (such as moisture, light and oxygen), because these factors will reduce the effectiveness of the drug. The most commonly used aluminum alloy is 8011-H18.

Here is a detailed description of 8011-H18 for medical blister foil:

8011-H18 Aluminum Alloy

1. Composition:

Aluminum content: approximately 98%, with the remaining 2% consisting of elements such as iron and silicon. These small amounts of additional elements provide the necessary strength and workability without compromising the alloy’s protective properties.

2. Mechanical Properties:

– Ultimate Tensile Strength: 125 – 165 MPa.

– Yield Strength: 110 – 145 MPa.

– Elongation: Typically less than 3%.

– H18 temper means the foil is completely hard with excellent stiffness and resistance to deformation. This is critical for blister packaging to maintain the integrity of the package, especially during the sealing process.

3. Barrier Properties:

– Excellent Moisture Barrier: 8011-H18 foil has excellent moisture barrier properties, which is critical for protecting sensitive medications from moisture.

– Light Barrier: Aluminum foil provides 100% barrier to light, which can degrade light-sensitive medications.
– Oxygen Barrier: It effectively prevents oxygen penetration, ensuring the shelf life of oxygen-sensitive products.
– Chemical Resistance: The alloy is resistant to many chemicals, helping to protect medications from potential contamination.

4. Processability and Sealability:

Formability: Although aluminum foil is very hard (H18), it is still malleable enough to be formed into blister packs, which typically require complex forming.

Heat Sealability: 8011-H18 aluminum foil is compatible with a variety of heat-sealable coatings, so it can be effectively sealed to a variety of substrates, such as PVC (klorur tal-polivinil) or PVDC (klorur tal-poliviniliden) commonly used in blister packs.

5. Thickness:
– Typically, aluminum foil used in blister packs is 20 biex 25 microns thick, which provides the necessary barrier but is thin enough for patients to easily pierce the foil to access medication.

6. Other considerations:
– Cost-effectiveness: 8011-H18 aluminum foil is relatively cost-effective, balancing the need for high-quality protection with manufacturing efficiency.
– Printability: The surface of 8011-H18 aluminum foil can be easily printed, which is important for printing product information, branding and safety warnings directly on the packaging.

8011-H18 aluminum alloy is the material of choice for medical blister foil due to its excellent barrier properties, mechanical strength and compatibility with pharmaceutical regulations. Alumni foil 8011 ensures that drugs remain safe, effective and easily accessible to patients throughout their shelf life.