01 VMCPP + VMPET SOURCING
Metallized PET film (VMPET) and VMCPP: separate the layer roles
VMCPP and VMPET both carry a vacuum-deposited metal layer, but they should not be treated as the same procurement item. Start with the substrate and the job the web must perform in the laminate.
02 LAYER ROLE
Two metallized routes with different starting assumptions
VMPET is commonly evaluated as a metallized barrier or visual web that is paired with another sealant layer. VMCPP can combine a metallized barrier role with grade-dependent heat-seal behavior. Actual suitability depends on substrate, coating, metal deposition, treatment and the complete laminate.
- Laminates that need a metallic barrier or opaque visual layer
- Buyers comparing VMPET and VMCPP around sealing and structure
- Projects with defined OTR, WVTR, optical-density or metal-bond targets
- Substrate identity and which side carries the metal
- Optical density alone is not a complete barrier specification
- Metal adhesion, flexing and downstream lamination conditions
03 SELECTION MAP
Three decisions before supplier matching.
Barrier web first
Treat metallized PET as a distinct substrate choice. Define its laminate position, treatment, metal side and the separate layer responsible for sealing.
Barrier plus grade-dependent sealing
For metallized CPP, identify the sealing side, target seal conditions and whether the grade is expected to combine inner-web and barrier functions.
Specify more than appearance
Include optical density, metal adhesion and barrier values with test conditions, plus how flexing and lamination will be evaluated.
04 RFQ INPUTS
Metallized-film RFQ checklist
Use one substrate-specific brief rather than asking for “silver film” or “metallized roll.”
Open the RFQ brief builder ↗- 01
Choose VMPET, VMCPP or request a substrate recommendation
- 02
Packed product, pack format and complete laminate structure
- 03
Substrate gauge, total thickness, web width and tolerance
- 04
Metal side, treated side, lamination side and winding orientation
- 05
Target optical density and appearance requirement
- 06
OTR and WVTR targets with temperature, humidity and test method
- 07
Metal adhesion, flex-durability and downstream bond requirements
- 08
VMCPP seal conditions, roll format, trial quantity and recurring volume
05 BUYER QUESTIONS
Questions to resolve before the roll is quoted.
01What is the practical sourcing difference between VMPET and VMCPP?+
VMPET is usually approached as a PET-based metallized barrier web and normally needs a separate sealant layer. VMCPP is CPP-based and may provide a grade-dependent sealing role as well as a metallized barrier. The complete laminate and line conditions decide the fit.
02Is optical density enough to specify metallized film?+
No. Optical density helps describe the deposited metal layer and appearance, but the brief should also cover OTR, WVTR, metal adhesion, treatment, flexing, laminate bond and the applicable test conditions.
03Why must the RFQ identify the metal side and winding direction?+
The converter needs to know which surface will be laminated, printed, exposed or sealed and how the web unwinds into the process. Clear side orientation prevents an otherwise suitable roll from arriving in an unusable configuration.
04Can a VMPET grade be quoted as a direct VMCPP substitute?+
Not without redesigning the layer roles. PET and CPP bring different sealing, stiffness and conversion assumptions, so the complete structure and trial criteria should be reviewed before substitution.