What is Aluminum Foil?

Aluminum foil is a thin, pliable sheet made of aluminum metal. Aluminum foil is typically less than 0.2 millimeters (mm) thick.

Aluminum foil acts as an excellent barrier against moisture, light, oxygen, and other contaminants. It is an efficient conductor of heat, highly flexible and can be easily shaped, folded.

Aluminum Foil
Usage Temperature
Common Thickness
7um, 9um, 12um, 40um
Excellent barrier
Efficient conductor of heat
Barrier cut down after folded
Widely used for lamination.

Advantages of Aluminum Foil

The use of aluminum foil is ubiquitous in daily life, and it is commonly encountered in tearing open food and beverage packaging.

Aluminum foil is made from 99.0%-99.7% pure electrolytic aluminum through multiple rolling processes.

There are 9 Advantages of Aluminum Foil:

  1. Aluminum foil possesses moisture-proof, airtight, light-shielding, odor-preserving, non-toxic, and odorless characteristics.
  2. Aluminum foil packaging has excellent barriers against oxygen and moisture, making it a good barrier material.
  3. It has good heat resistance, high light reflectivity, and luster. It maintains good shape at high and low temperatures and is stable under high and low-temperature conditions between -73°C to 371°C without warping.
  4. Featuring an elegant silver-white metallic luster, aluminum foil is highly decorative.
  5. Lightweight with high ductility, thin thickness, and low unit area weight.
  6. Excellent light-shielding properties with a reflectivity of up to 95%.
  7. Strong protection capability, preventing packaged items from bacterial, fungal, and insect infestations.
  8. It has extremely good barrier properties to prevent moisture absorption, oxidation, and volatile deterioration of packaged contents as well as excellent moisture and oxygen barrier properties.
  9. Aluminum foil is easy to process and can be compounded with various plastic films and papers.

Drawbacks of Aluminum Foil

Aluminum foil also has some defects when used in packaging.

  1. Low strength, prone to tearing, unsuitable for standalone packaging, easily fractures during folding then leading to punctures, and not resistant to acids and alkalis.
  2. Aluminum foil is brittle, fractures easily, and is relatively challenging to laminate.
  3. Aluminum foil has poor acid resistance. Therefore, when packaging juices or acidic items, it is generally not placed in the inner sealing layer to ensure the acid does not penetrate and cause delamination.
  4. Lacks heat-sealing properties, cannot serve as the innermost layer of a laminate pouch, and is only suitable as an intermediate layer material for the bag.

Metallized Materials

The high barrier properties of aluminum foil make it a favorite in flexible packaging, but its cost is relatively high.

To reduce costs, film manufacturers have explored metalized material, which not only possesses the characteristics of aluminum foil but also comes with the advantage of being cost-effective.

When selecting material structures, metalized bags can be considered as a substitute.

Aluminum Foil
Normal MBOPP
  • Aluminum Foil OTR≤0.5cm³/(m²∙24h∙0.1Mpa), and WVTR≤0.5g/(m²∙24h). It has the best barrier.
  • After metalization, the PET OTR increased from 120 to 2.0cm³/(m²∙24h∙0.1Mpa), and WVTR increased from 50 to 2.0g/(m²∙24h), the barrier property increased exponentially.
  • Nylon film lacks oxygen barrier properties and typically offers moderate water resistance. However, after metallization, its oxygen and water barrier performance is significantly enhanced.
  • BOPP film has poor water resistance. After metallization, the water resistance of ordinary barrier BOPP (MBOPP) is significantly improved, and its oxygen barrier properties are simultaneously enhanced.

    The high barrier MBOPP can achieve oxygen and water barrier levels even ≤1.0cm³/(m²∙24h∙0.1Mpa) and ≤1.0g/(m²∙24h).

Uses of Aluminum Foil

Due to the versatile properties of aluminum foil, it serves a variety of purposes, such as food packaging, cooking and baking, medical packaging, insulation, grilling and barbecuing, arts and crafts, electrical conductivity, decoration and wrapping, reflective insulation, and hairdressing.

In Food Packaging:

  • Common packaging structure PET/AL/PE is suitable for most food items requiring barrier properties.
  • For stand-up pouches with a spout, such as tomato sauce, PET/AL/PET/PE structure is used. The aluminum layer provides barrier properties, and the dual PET layers lend rigidity to the stand-up pouch. It is also suitable for baby food and daily food.
  • For retort pouches, the PET/AL/NY/RCPP structure is an excellent choice.
  • Stand-up paper bags typically use AL for barrier properties, like paper//PE//AL//PE.

Even in non-food applications, AL plays a significant role.

  • Cleaning agents often use NY/AL/PE structure, where the aluminum layer not only blocks light but also prevents the unpleasant odor of the cleaning agent.

The versatility and protective properties of aluminum foil make it a valuable material in various industries and everyday applications.

Start With KDW

Please contact us for more info of the flexible packaing, our expert term will get in touch with you timely.

+86 13559233681(Wechat, Whatsapp)

No1, Anbian Rd, Torch High-Tech Zone (XiangAn), Xiamen, Fujian, China