What Is Coated Polyester Metallized Film (Pre-Coated PET Metallized Film)?
Jul 09,2026 | FOSHAN CAILONG METALLIC PACKAGING MATERIAL CO.,LTD
Coated polyester metallized film — also referred to as pre-coated PET metallized film or primer-coated metallized PET — starts with a transparent BOPET base film that undergoes vacuum metallization on one side, while the non-metallized surface receives a special surface treatment (coating) .
This coating serves a critical function: it dramatically improves lamination bond strength when the film is later combined with other substrates (PE, CPP, paper, aluminum foil). Without this treatment, the non-metallized PET surface can delaminate under stress or wet conditions.
Key distinction: Standard metallized PET has no treatment on the non-metal side. Pre-coated metallized PET has a functional coating on the non-metal side specifically engineered for stronger adhesion in multi-layer laminates.
How It Differs from Standard Metallized PET
|
Property |
Standard Metallized PET |
Pre-Coated (Coated) Metallized PET |
|---|---|---|
|
Non-metal side treatment |
None |
Special surface coating |
|
Lamination bond strength |
Moderate |
Significantly higher |
|
Suitability for wet/oily contents |
Limited |
Excellent |
|
Retort / boil-proof capability |
Requires careful selection |
Designed for demanding processes |
|
Printability (non-metal side) |
Poor without corona |
Good to excellent |
|
Typical applications |
Dry snacks, simple labels |
Liquid pouches, retort, electronics |
Key Properties
1. Superior Mechanical Performance
-
Excellent flatness and stiffness — runs smoothly on high-speed packaging lines
-
Good tensile strength and dimensional stability
-
Resists curling and wrinkling during lamination and printing
2. Heat & Chemical Resistance
-
Withstands temperatures encountered in heat-sealing and lamination processes
-
Resists attack from oils, acids, and common solvents found in food and industrial environments
3. Outstanding Dimensional Stability
-
Low thermal shrinkage ensures register accuracy in multi-color printing
-
Maintains flatness across varying humidity conditions
4. Strong Metal Adhesion
-
The vacuum-deposited aluminum layer bonds tightly to the PET base
-
No flaking or peeling during converting (slitting, rewinding, bag-making)
5. High Barrier Performance
-
Oxygen barrier: OTR typically ≤2 cc/m²·24h (can reach ≤0.5 with ultra-high-barrier grades)
-
Moisture barrier: WVTR typically ≤2 g/m²·24h (can reach ≤0.5)
-
Opaque to light — protects light-sensitive contents
6. Metallic Gloss Finish
-
Attractive silver mirror-like appearance enhances shelf presence
-
Compatible with reverse printing and over-lamination for branding

Applications
Food Packaging
-
Coffee and tea pouches (oil resistance + barrier)
-
Snack food bags (crisps, nuts, biscuits)
-
Condiment sachets (ketchup, soy sauce, chili oil)
-
Retort pouches (ready meals, soups, pet food) — when combined with appropriate sealant layer
Pharmaceutical Packaging
-
Blister backing foil lidding
-
Strip pack wrapping for tablets and capsules
-
Moisture-sensitive nutraceutical packaging
Cosmetic & Personal Care
-
Lotion sachets and sample packs
-
Face mask packaging
-
Perfume box inserts and decorative wraps
Electronic Components
-
Phone reflector film — the metallic surface acts as a light reflector in backlight units and display modules
-
EMI shielding layers
-
Insulation spacers and die-cut parts in batteries and PCBs
Why phone reflector film? The combination of high reflectivity (from the aluminum layer), dimensional stability, and thin gauge makes pre-coated metallized PET ideal for directing light evenly across LCD/LED backlight assemblies.
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 grade) |
|
Optical density |
1.5–2.5 (depending on application) |
|
Surface tension (non-metal side) |
≥44 mN/m (treated) |
|
Coefficient of friction |
0.3–0.6 (adjustable) |
|
Tensile strength (MD/TD) |
≥170 MPa |
|
Elongation at break |
≥80% |
FAQ (SEO Snippet Target)
Q: What is pre-coated PET metallized film?
A: It is BOPET film that is vacuum-metallized on one side and has a special surface coating on the non-metallized side to improve lamination bond strength with other substrates.
Q: Can pre-coated metallized PET be used for retort packaging?
A: Yes. When combined with a suitable sealant film (such as CPP or RCPP), the pre-coated surface provides the adhesion needed to survive high-temperature retort processing.
Q: Is pre-coated metallized PET suitable for phone reflector film?
A: Yes. Its high reflectivity, dimensional stability, and thin gauge make it a preferred material for backlight reflectors in mobile phone displays.
Q: How does the coating improve lamination strength?
A: The coating increases surface energy and provides chemical bonding sites, allowing adhesives to anchor more effectively to the PET surface than untreated PET.
Q: Is this film printable on the non-metal side?
A: Yes. The special surface treatment enables good ink adhesion for reverse printing (commonly used in laminated packaging structures).
Conclusion
Coated (pre-coated) polyester metallized film bridges the gap between standard metallized PET and demanding packaging requirements. By treating the non-metallized surface, manufacturers achieve stronger laminations, better process reliability, and expanded application scope — from everyday snack pouches to precision electronic components like phone reflector films.
