Aluminum and aluminum alloy foil for blister packaging
Aluminum and aluminum alloy foil for blister packaging is an ultra-thin product with a thickness of 0.02-0.1mm . It offers excellent barrier properties, sealing, and formability, making it indispensable for packaging in the pharmaceutical, food, and cosmetic sectors. This type of foil is typically made from aluminum-manganese alloys such as 8011 and 8021. By adding 1-1.5% manganese to enhance strength and corrosion resistance while maintaining an elongation exceeding 95% , it can be cold-stamped into a variety of complex blister shapes. Compared to plastic packaging, aluminum foil blisters offer superior oxygen barrier properties (oxygen permeability < 0.1cc/ ㎡・day ) and light-shielding properties, effectively extending product shelf life and making it particularly suitable for products requiring high freshness and oxidation resistance.
The production process of aluminum and aluminum alloy foil for blister packaging centers on high-precision rolling, requiring multiple rolling and annealing passes. First, aluminum ingots with a purity exceeding 99.7% are melted with a manganese alloy in appropriate proportions and cast into 6-10mm thick cast-rolled coils. A continuous casting and rolling process ensures uniform composition and fine grains. The cast-rolled coils are then rolled through a cold rolling mill in multiple passes, gradually thinning to 0.05-0.1mm, with each pass maintaining a reduction of 30-50%. Annealing treatments (300-350°C) are performed between passes to eliminate work hardening and maintain the foil’s plasticity. The finished foil is slit and coiled to maintain a thickness tolerance within ±3μm and a surface finish of Ra ≤ 0.4μm. Oiling is also performed (oil film volume 2-5mg/㎡) to facilitate subsequent stamping and forming. Finally, pinhole detection (number ≤ 1 pinhole/㎡, diameter ≤ 0.3mm) and mechanical property testing are performed to ensure compliance with packaging requirements.
In the pharmaceutical packaging sector, aluminum foil for blister packaging is the primary packaging material for tablets and capsules. Blister packaging for oral solid dosage forms typically utilizes a composite structure of aluminum foil + PVC/PP. Aluminum foil, used as the lid or blister base, leverages its barrier properties to protect the drug from moisture and oxidation. For example, the shelf life of a particular antibiotic tablet packaged in 8011 aluminum foil was extended from 18 months to 24 months. For medications requiring protection from light (such as vitamins), matte-finished aluminum foil offers a light shielding rate of over 99%, effectively protecting the active ingredients. In medical device packaging, aluminum foil composite materials for sterilization packaging can withstand high-temperature steam sterilization at 121°C, maintaining a stable tear force of 5-15N, making it easier for medical staff to operate. Using this aluminum foil in the packaging of an infusion set has resulted in a sterile shelf life of up to three years.
Demand for aluminum foil for blister packaging continues to grow in the food and cosmetics industries. Individually packaged foods like chocolate and chewing gum utilize 0.03-0.05mm aluminum foil blisters, which not only preserve the flavor but also allow for the creation of exquisite three-dimensional patterns through stamping, enhancing product appeal. One brand of chocolate has seen its shelf life extended by 30% using aluminum foil blister packaging. Health supplements such as fish oil and protein powder are packaged using aluminized composite aluminum foil, which combines barrier properties with printability, enabling multi-color, high-quality printing. In the cosmetics sector, aluminum foil blisters are used for sample packaging of products like serums and facial masks. Their excellent sealing properties prevent the volatilization of ingredients, while the foil’s metallic texture enhances the product’s quality. A skincare brand has reduced its sample breakage rate by 50% using this packaging.
With rising consumption and environmental awareness, the performance and applications of aluminum and aluminum alloy foil used in blister packaging are constantly innovating. Manufacturers have developed ultra-thin aluminum foil (0.02mm thick), reducing material usage by 20%. Microalloying technology has also enhanced foil strength, increasing the stamping pass rate from 90% to 98%. To address environmental concerns, biodegradable aluminum foil composites have been developed, reducing the foil layer thickness to 0.015mm for easier recycling and separation. In terms of functionalization, antibacterial aluminum foil has been developed, using surface treatment to inhibit the growth of bacteria like E. coli, expanding its application in infant food packaging. In the future, with the separation of pharmaceuticals and the development of small-scale e-commerce packaging, aluminum foil for blister packaging will continue to become thinner, stronger, and more environmentally friendly, providing a superior solution for consumer product packaging.
