Metallized PET Film: Barrier or Adhesion?

Metallized PET Film should be selected from the package failure, not from one maximum-performance label. A shelf-life problem caused by oxygen or moisture entry requires a different evidence set from metal transfer, weak lamination or delamination during wet-heat exposure.

A Metallized Film Supplier should ask whether the priority is transmission resistance, metal-layer adhesion, process durability or a combination. Cailong’s published range separates ultra-high-barrier, chemically enhanced and high-adhesion metallized film families, so the enquiry should identify the dominant interface risk.

When Barrier Is the Dominant Requirement

Choose a barrier-focused evaluation when the product is highly sensitive to oxygen, moisture or light and the current pack fails shelf-life targets despite intact seals. Compare OTR and WVTR under stated conditions and confirm whether the figures apply to single film, cured laminate or finished package.

Then repeat the critical measurement after printing, lamination, pouch making and distribution simulation. A strong incoming number has limited value if folding or abrasion damages the deposited layer.

When Adhesion Is the Dominant Requirement

Choose an adhesion-focused evaluation when metal transfers during tape checks, the laminate separates, or the interface changes after heat, humidity, oil or chemical exposure. Document which interface failed; adhesive-to-metal failure is different from metal-to-PET failure or seal-layer separation.

Record adhesive chemistry, coat weight, drying, cure time and test conditions. A higher bond result on one laboratory strip does not guarantee that every package condition is covered.

Do Not Trade One Failure for Another

A high-adhesion grade still needs the required barrier, and an ultra-high-barrier grade still needs adequate converting durability. Use one approval matrix containing transmission, optical appearance, metal transfer, bond strength, seal integrity and post-abuse performance.

Send Cailong the current laminate, failure location, required OTR and WVTR, exposure conditions and retained samples. The recommendation can then target the actual package risk instead of over-specifying one property.