Aluminum Foil (AL)
Aluminum Foil (AL) is a thin sheet of pure aluminium used in laminated packaging as the highest-barrier layer.
It provides complete protection against:
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Oxygen (Oâ‚‚)
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Moisture (water vapor)
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Light (UV & visible light)
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Odor/aroma transfer
This is why aluminum foil is commonly used for:
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Coffee bags
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Powder packaging
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Pharmaceuticals
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Retort pouches
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High-shelf-life food products
​Key properties of Aluminum Foil:
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Perfect light barrier → protects sensitive products
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Highest oxygen & moisture barrier of all materials
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Good thermal stability
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Metallic appearance (but cannot print directly without coating)
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Must be laminated with PE or CPP for heat sealing
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No other film (not even VMPET) can match the 100% barrier performance of true aluminum foil.
In laminated structures, aluminum foil is usually placed in the middle layer:
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PET / AL / PE
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PET / AL / CPP
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Kraft Paper / AL / PE
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NY / AL / PE
Types of AL used in packaging
Standard Aluminum Foil (Bare AL Foil)
This is the most common type used in plastic laminations.
Typical thickness:
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7 mic
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9 mic (most common)
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12 mic
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20 mic (special use)
Pharmaceutical-Grade Aluminum Foil
Special aluminium foil designed for medicines.
Features:
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Excellent barrier
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Special coatings
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Extremely stable
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Resistant to corrosion
Retort-Grade Aluminum Foil
Designed to withstand 121°C – 135°C sterilization for retort pouches.
Common structure:
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PET / AL / NY / CPP
or -
PET / AL / CPP