Part 3.2: Pharmaceutical Packaging  Please click here to download the pdf. A number of alufoil’s properties combine to provide a convenient, safe and versatile packaging format for tablets, creams, liquids and powders covering an enormous variety of pharmaceutical products. Alufoil’s unrivalled barrier properties totally exclude moisture, oxygen and other gases, micro-organisms and light, thus maintaining sensitive products in peak condition for long periods. Foil can be supplied in a completely sterile condition thanks to the annealing temperature and final conditioning processes during its manufacture. It is not hazardous to health, and many suppliers offer dedicated ‘clean-room’ printing and laminating, printing and packing facilities to ensure medical standards of sterility of the final product.* Important properties Barrier Alufoil’s total barrier to light, atmosphere and liquids is the principle reason for its use in pharmaceutical applications. Deadfold and mechanical properties Alufoil is strong and can be laminated with other materials. By using different alloys alufoil can be given a choice of characteristics which make it suitable for ‘pushthrough’ lids or pre-formed trays for tablets. Thanks to its ‘deadfold’ property, collapsible tubes made from alufoil laminates do not, when squeezed, draw air and contamination into contact with the product. Hygiene and safety Alufoil does not harbour bacteria. It can be supplied in a fully sterile condition. Many suppliers offer alufoil packaging materials produced in hygienic ‘clean-room’ facilities. For tamper evidence and anti-counterfeiting security, holograms and other techniques can be readily applied to alufoil. Sustainability Alufoil is weight-saving, effective and minimises the amount and diversity of packaging material needed. Added to this reduction at source, it also helps to preserve valuable pharmaceutical products, so cutting waste of materials and energy. Aluminium can be repeatedly recycled at a fraction of its original energy cost. Modern separation techniques allow aluminium foil in household waste to be extracted and recycled. Even in cases where the metal is uneconomic to recover directly, its high energy content can be efficiently recovered in the form of heat. Applications Blister packs Alufoil is particularly suitable for blister packs because of the range of mechanical properties available. 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 for more and more alufoil blister packs. Strip packs Strip packs can be produced from aluminium or in combination with paper or plastics. A key requirement is that they should be easy to tear open. Alufoil is readily printed and its malleability and deadfold characteristics are important in these applications, allowing the metal to closely form to the shape of the tablet. Strip packs provide economical high barrier performance and can be filled at high speeds on modern, sterile, filling lines. Sachets and pouches 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 an effective packaging solution 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 the hospital treatments. Alufoil sachet packs are robust and keep the product in good condition for long periods. They withstand rigorous ‘burst’ tests and are convenient and economical to transport. Printed designs, colour coding and anti-counterfeiting finishes are also fully available. Heat sealed membranes and closures 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 effect 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 and providing tamperevidence. Safety information can be printed on the alufoil seal itself if required. Collapsible tubes 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’. This means that a tube made from an alufoil laminate can be designed not to ‘spring back’ when squeezed and so draw ambient air and contamination back into the tube. Tubes with holographic or other optical effects are also available. As well as offering decorative design opportunities, these surface finishes can be used as valuable tools against product counterfeiting. *Clean room conditions to Class 100,000 are generally available to meet most pharma/medical standards in the slitting/packing of materials.
|
