Many of alufoil’s properties combine to provide user-friendly, safe and versatile packaging formats for pharmaceutical tablets, creams, liquids and powders. Alufoil’s excellent barrier properties totally exclude moisture, oxygen and other gases, micro-organisms and light, maintaining degradable products in peak condition over long periods.
Foil comes in a completely sterile condition due to the annealing temperature and final conditioning processes. It is not hazardous to health, and many suppliers offer dedicated ‘clean-room’ printing and laminating or printing and packing facilities to ensure medical standards of sterility.
Alufoil is particularly suitable for blister packs because of its range of mechanical properties. Depending on the alloy and its treatment, alufoil can be made more brittle, tougher or more ductile. It can also be combined with other materials like paper or plastics. Blister packs are tamper-evident and can be designed to be ‘child-proof’ or to provide more secure access.
Most blister packs consist of a preformed plastic tray with an aluminium foil closure manufactured to facilitate the necessary ‘push-through’ characteristic. A recent development is the all-aluminium blister pack. The cold-formed trays are filled with the medicine in aqueous form and freeze dried into individual tablets, which adopt the shape of the individual alufoil compartment. All-aluminium packs are also used for diagnostic products, ointments, and light sensitive formulations where total barrier performance is required. As product counterfeiting has become an increasingly serious issue, holographic effects are now being used on more and more alufoil blister packs.
Strip packs can be produced entirely from aluminium or in combination with paper or plastics, all of which are printable. A key requirement is the ability to tear open easily. Alufoil’s malleability and deadfold characteristic are important in these applications, allowing the metal to closely match the shape of the tablet. Strip packs provide economical high barrier performance and can be filled at high speeds on sterile filling lines.
The sensitive nature of most pharmaceutical preparations demands that the packaging provides a perfect barrier to moisture and often to light. Alufoil laminated sachets provide packaging solutions for many products, whether in powder, cream or liquid form. Large alufoil pouches are also used to store, transport and dispense sterile fluids used in hospital treatments.
Alufoil sachets are robust and keep the product in good condition over long periods. They withstand rigorous ‘burst’ tests and are convenient and economical to transport. Printed designs, colour coding and anti-counterfeiting finishes are available.
Many medicines are supplied in glass, plastic or metal containers. Alufoil, laminated with paper or plastic, is frequently used as a heat-sealed membrane hermetically closing the container, usually under a plastic screw cap. The localised heat needed to affect the sealing process is generated by an electrical induction process after the screw caps are applied on the filling and capping line. The resulting alufoil membrane provides excellent barrier properties preventing moisture or gas transmission as well as tamper evidence. Safety information can be printed on the alufoil seal if required.
Alufoil is frequently used as a key component in tube laminates. Apart from providing excellent barrier performance to protect sensitive creams, alufoil offers the advantage of ‘deadfold’. So a tube made with alufoil laminate can be designed not to ‘spring back’ when squeezed, which can draw ambient air and contamination back into the tube. Tubes with holographic or other optical effects are available. In addition to decorative design opportunities, these surface finishes can be used as valuable tools against product counterfeiting.