Oxygen Transmission Rate Of Aluminium Foil

Aluminum foil itself is a very good oxygen barrier material with extremely low oxygen permeability. Generally, the oxygen transmission rate of aluminum foil is usually 0.01 to 0.1 cm³/m²·h per square meter per hour (cm³/m²·h), or even lower. Pure aluminum foil (thickness ≥12μm) has excellent oxygen barrier properties, but in actual applications, due to the presence of tiny pinholes or cracks in the aluminum foil, its oxygen permeability will increase slightly. Therefore, pure aluminum foil is often used in combination with other materials to enhance physical strength and maintain its excellent oxygen barrier properties.

In order to further improve the barrier properties of aluminum foil, it is usually combined with the following materials:

– Plastic film: such as PET (polyester), BOPP (biaxially oriented polypropylene), PE (polyethylene), etc. After compounding, aluminum foil provides an oxygen barrier layer, and plastic film provides mechanical strength and heat sealing properties.

– Paper: such as aluminum foil combined with kraft paper, used for packaging of tea, cigarettes, etc., with both barrier properties and printability.

– Nylon (PA): Aluminum foil is compounded with nylon to improve the puncture resistance and flexibility of the packaging.

– EVOH (ethylene-vinyl alcohol copolymer): After compounding with aluminum foil, it forms a high-barrier multilayer structure, which is suitable for high-end food packaging.

Oxygen transmission rate of aluminum foil composite film materials:

After aluminum foil is compounded with other materials, the oxygen transmission rate can be significantly reduced, and the specific value depends on the composite structure and material thickness. For example:

– Aluminum foil/PET/PE composite film: The oxygen permeability can be as low as 0.01-0.05 cm³/(m²·24h·atm).

– Aluminum foil/nylon/PE composite film: The oxygen permeability can be controlled at 0.005-0.02 cm³/(m²·24h·atm).

– Multi-layer high-barrier composite film (such as aluminum foil + EVOH + PET + PE): The oxygen permeability can be lower than 0.001 cm³/(m²·24h·atm), which is suitable for packaging products that are extremely sensitive to oxygen.

Aluminum foil can effectively block oxygen, moisture and other gases, thereby extending the shelf life of products and preventing oxidation and deterioration. Due to its excellent oxygen barrier properties, aluminum foil is widely used in the following packaging fields:

– Food packaging: such as packaging of easily oxidized foods such as coffee, milk powder, nuts, meat, etc., to extend the shelf life.

– Pharmaceutical packaging: such as packaging of tablets, capsules, injections and other medicines to prevent oxidation and deterioration of medicines.

– Electronic product packaging: such as moisture-proof and anti-oxidation packaging of oxygen-sensitive electronic components such as PCB boards and IC integrated circuits.

– Industrial product packaging: such as moisture-proof and anti-oxidation packaging of chemicals, precision instruments, etc.

Aluminum foil is widely used in food, medicine, electronics and other fields due to its excellent oxygen barrier properties. By compounding with other materials (such as plastic film, paper, nylon, EVOH, etc.), its barrier properties and mechanical properties can be further improved to meet the packaging needs of different products. The oxygen transmission rate of the composite aluminum foil material can be significantly reduced, providing more reliable protection for the product.