Enhanced adhesion metallized PET film (also referred to as chemically treated surface metallized PET) is produced by applying a chemical treatment to one side of a BOPET base film before vacuum metallization. The aluminum layer is deposited directly onto this chemically activated surface, resulting in significantly stronger metal-to-film adhesion compared to standard untreated metallized PET.
Key difference from standard metallized PET: In standard grades, the aluminum is deposited on a corona-treated or untreated surface. In enhanced adhesion grades, a dedicated chemical primer/treatment is applied to the base film prior to metallization, creating covalent bonding sites for the aluminum atoms.

How It Compares to Standard and Coated Metallized PET
| Property | Standard Metallized PET | Coated (Pre-Coated) Metallized PET | Enhanced Adhesion (Chemically Treated) Metallized PET |
|---|
| Treatment location | Usually corona on metal side | Non-metal side coated for lamination | Metal side chemically treated for adhesion |
| Aluminum adhesion | Moderate | Moderate (metal side untreated) | Excellent |
| Water resistance | Poor (delamination risk) | Good (lamination helps) | Excellent |
| Pasteurization / boiling | Not recommended | Possible with proper structure | Yes, directly suitable |
| Lamination bond strength | Moderate | High (due to coating) | Moderate (metal side optimized, non-metal side may need separate treatment) |
| Primary advantage | Low cost | Strong lamination | Strong metal adhesion + water resistance |
Key Properties
1. Superior Aluminum Layer Adhesion
- Chemical treatment creates a reactive surface that anchors the aluminum layer firmly
- No peeling, flaking, or micro-cracking during converting (slitting, bag-making, filling)
- Essential for liquid, moist, or oily contents
2. Excellent Water Resistance
- The enhanced metal-to-film bond resists hydrolysis and delamination when exposed to moisture
- Suitable for pasteurization (hot water bath up to ~85–95°C) and boil-proof applications
3. High Barrier Performance
- Oxygen barrier: OTR typically ≤2 cc/m²·24h (ultra-high barrier grades ≤0.5)
- Moisture barrier: WVTR typically ≤2 g/m²·24h (ultra-high barrier grades ≤0.5)
- Opaque to light – protects light-sensitive products
4. Outstanding Mechanical Properties
- Excellent flatness and stiffness for high-speed packaging lines
- Good tensile strength and dimensional stability
- Flex-crack resistance – the aluminum layer withstands repeated bending without fracturing, critical for pouches and sachets
5. Metallic Gloss Finish
- Bright silver appearance enhances shelf appeal
- Compatible with reverse printing and lamination
6. Pasteurization Compatibility
- Can withstand pasteurization processes (e.g., 85°C for 30 minutes) without delamination or barrier loss
- Enables extended shelf life for refrigerated and ambient-stable products

Applications
Food Packaging Requiring Pasteurization
- Sauce and condiment pouches (ketchup, mayonnaise, salad dressing)
- Soup and broth sachets (pasteurized for ambient storage)
- Baby food pouches (sterilized via hot water bath)
- Pickled vegetable and kimchi packaging (acidic + moisture environment)
Coffee & Tea
- Stand-up pouches for roasted coffee beans (oil resistance + barrier)
- Tea bag overwrap (moisture barrier + flex-crack resistance)
Pharmaceutical & Nutraceutical
- Moisture-sensitive tablet and capsule packaging
- Powder sachets (protein, electrolyte mixes)
Cosmetics & Personal Care
- Lotion sample sachets
- Shampoo and conditioner refill pouches
- Face mask packaging (requires water resistance)
Meat, Seafood & Dairy
- Processed meat pouches (ham, sausages) – pasteurization step
- Cheese packaging (moisture barrier + flex-crack resistance)
Technical Specifications (Typical Range)
| Parameter | Value |
|---|
| Base film thickness | 12–50 µm |
| Aluminum layer thickness | 300–500 Å (standard); down to 40 Å (ultra-thin) |
| Optical density | 1.5–2.5 |
| Surface tension (metal side) | ≥52 mN/m (after treatment) |
| Coefficient of friction | 0.3–0.6 (adjustable) |
| Tensile strength (MD/TD) | ≥170 MPa |
| Elongation at break | ≥80% |
| Pasteurization test | 85°C / 30 min – no delamination |
| Water immersion test | 24h @ 23°C – no adhesion loss |
FAQ (SEO Snippet Target)
Q: What is enhanced adhesion metallized PET film?
A: It is BOPET film that receives a chemical treatment on the metallization side before vacuum aluminum deposition, resulting in much stronger aluminum adhesion than standard metallized PET.
Q: Can enhanced adhesion metallized PET be pasteurized?
A: Yes. The strong metal-to-film bond and water resistance allow it to withstand pasteurization processes (e.g., 85°C hot water bath) without barrier loss or delamination.
Q: How does it differ from pre-coated metallized PET?
A: Pre-coated (coated) metallized PET treats the non-metalside for better lamination. Enhanced adhesion treats the metalside for better aluminum anchorage and water resistance. They solve different problems.
Q: Is this film suitable for coffee packaging?
A: Yes. Its oil resistance, barrier, and flex-crack resistance make it an excellent choice for coffee stand-up pouches and valve-equipped bags.
Q: Does enhanced adhesion affect printability?
A: The non-metal side can be corona-treated or coated separately for printing. The enhanced adhesion treatment is only on the metal side and does not interfere with reverse printing.
Conclusion
Enhanced adhesion metallized PET film fills a specific but important niche: applications where water resistance, pasteurization, and strong aluminum anchorage are critical. By chemically activating the metallization surface, manufacturers eliminate the weak point of standard metallized films — metal peeling under wet or thermal stress.
For converters producing pouches for sauces, soups, baby food, and other pasteurized products, this grade offers a reliable, high-performance alternative to foil laminates or expensive multi-layer structures.