Aluminum plating and aluminum foil, do you know the difference?

1. What is Metallized Film? What is Aluminum Foil? Metallized Film ≠ Aluminum FoilMetallized film (Metalized film) is a type of plastic film that has a very thin layer of metal aluminum (approximately 300nm) coated on its surface using a special process. The commonly used method is vacuum metallizing, where metal aluminum is melted and vaporized at high temperatures under a high vacuum. The aluminum vapor then condenses and deposits on the surface of the plastic film, giving it a metallic sheen. The most widely used types of metallized films are polyester metallized film (VMPET) and CPP metallized film (VMCPP).Aluminum foil composite film (Aluminum foil composite film), on the other hand, typically consists of aluminum foil laminated with other packaging materials, often forming a three-layer structure such as: printing layer (PET, BOPP)/barrier layer (AL)/heat seal layer (PE, CPP), etc.2. Which is Superior: Metallized Film or Aluminum Foil?Poor Light Blocking: Aluminum foil provides complete light blockage, whereas metallized film's light-blocking capability is far inferior, resulting in a shorter shelf life for food products.Easy Delamination: The metallized layer can migrate and peel off, which poses a risk to food safety.Poor Corrosion Resistance: Metallized film is susceptible to chemical and physical factors, leading to corrosion. It easily oxidizes in humid environments, affecting its appearance and durability.Inferior Moisture and Oxygen Barrier: The oxygen and moisture permeability of metallized packaging is much higher compared to aluminum foil packaging, which impacts the shelf life of food.Not Heat Resistant: The metallized layer oxidizes and blackens under high temperatures.Production and Usage Defects: Products made from composite metallized film often face issues during production and use, such as white spots, metallization transfer, weak metallization, and metallization disappearing, affecting the appearance of the bag, food shelf life, and food safety.3. How to Accurately Distinguish Between Metallized Film and Aluminum Foil?Visual Inspection: Aluminum foil is less shiny than metallized film. Metallized bags can reflect images, although matte film metallized bags, which resemble aluminum foil in appearance, are an exception. You can block the bag's opening and look inside against a strong light; if it's opaque, it’s an aluminum foil bag, and if it allows light through, it’s a metallized bag.Touch: Aluminum foil bags feel thick, sturdy, and heavy, whereas metallized bags feel lighter and softer.Folding: Aluminum foil bags are prone to leaving creases when folded, while metallized bags are not and quickly rebound after being creased.Twisting: Aluminum foil bags retain twists for a few seconds and are not easy to rebound, whereas metallized bags quickly spring back from twists.Burning Test: Aluminum foil is not easily flammable and will curl when exposed to fire, leaving behind gray aluminum residue. When a metallized bag is burned, it exhibits the burning characteristics of different plastic films and leaves no aluminum residue.