What are the advantages of aluminum foil packaging bags, and how can you differentiate between aluminum foil bags and metallized bags?

Bright surface aluminum foil composite material (PET/AL/PE) and matte surface aluminum foil composite material (MPET/AL/PE) are two commonly used packaging materials, characterized by being hygienic, opaque, and resistant to high and low temperatures. Pure aluminum foil packaging bags offer superior protective performance compared to metallized bags, especially suitable for products like food .

Materials: Bright surface aluminum foil composite material (PET/AL/PE), matte surface aluminum foil composite material (MPET/AL/PE).

Characteristics of aluminum foil: The surface of aluminum foil is very clean and hygienic, and no microorganisms can grow on it, allowing direct contact with food without any health risks. As an opaque packaging material, it offers excellent protection for products sensitive to sunlight, such as oily products, solid beverages, coffee, etc. Aluminum foil does not allow penetration under high or low temperatures. It has a low permeability to air and moisture, which protects the contents well. Aluminum foil itself is non-volatile; neither it nor the packaged food will dry out or shrink. It is an odorless and tasteless packaging material that will not affect the taste of the packaged food. It has stable performance, can withstand various high and low temperature environments, and has certain corrosion resistance.

Why add a layer of pure aluminum foil inside the packaging bag? Aluminum foil is widely used as a barrier layer, for heat exchange, and as a conductor. Typically, the aluminum foil used in paper-based beverage packaging and food bags is only 6.5 micrometers thick. This thin layer of aluminum provides waterproofing, flavor preservation, protection against harmful microbes, and contamination. It is opaque, silvery white, glossy, and has good barrier properties, high/low temperature resistance, oil resistance, heat sealability, light blocking, aroma preservation, no off-flavor, and flexibility.

Metallized packaging bags are plastic films coated with a thin layer of aluminum powder for decorative purposes. These are also called aluminum-plastic bags. Aluminum foil packaging bags, as the name suggests, contain aluminum foil (pure aluminum) in their inner structure and are commonly referred to as aluminum foil packaging bags or pure aluminum bags. In fact, aluminum foil bags are made by laminating various plastic films with 99.9% pure aluminum and then forming, sealing, and cutting the bags. Performance-wise, they offer better cooling effects than metallized bags; pure aluminum bags completely block light, while metallized bags only provide light shielding. Material-wise, pure aluminum bags are made of pure aluminum with high purity and are soft materials; metallized bags contain composite materials and are brittle. In terms of use, pure aluminum bags are more suitable for vacuum sealing, such as for cooked foods and meats, while metallized bags are suitable for tea leaves, powders, etc. Cost-wise, the unit price of pure aluminum bags is higher than that of metallized bags. Hold the bag up to a light source or sunlight; if light can be seen through the bag, it's metallized foil; if not, it's pure aluminum foil.

In appearance, the two types of bags are not much different. The same product may lose moisture and experience a large increase in microbial growth within a month when stored in a metallized bag. In contrast, it might take half a year for similar issues to occur in an aluminum foil bag. To ensure the quality of the contents, many packages are vacuum sealed. After vacuuming, the internal oxygen is reduced, preventing microbial growth and thus protecting the product. Additionally, aluminum foil bags are very stable and generally unaffected by external environmental factors that could cause deterioration. Functional differences between the two types of bags are significant. Aluminum foil bags, with their pure aluminum layer, have far superior moisture-proofing, light-blocking, water-resistance, and anti-oxidation properties compared to metallized bags. Long-lasting durability is synonymous with aluminum foil bags. Both types of bags can be printed with designs; aluminum foil bags feel softer, while metallized bags feel harder. Therefore, aluminum foil bags are more suitable for food, pharmaceuticals, chemical products, and some electronic and mechanical accessories that require sealing. Metallized bags are often used for fast-moving consumer goods, not because metallized bags are inferior but rather because they demonstrate a high cost-performance ratio.