December 6, 2026
Flexible barrier packaging is almost always a multi-layer laminate, not a single material, because no one polymer blocks oxygen, moisture, and light equally well while also sealing reliably and surviving handling. A typical structure pairs an outer layer for print quality and puncture resistance, a barrier core for oxygen and moisture blocking, and an inner sealant layer chosen for heat-seal performance against the product.
EVOH (ethylene vinyl alcohol) is one of the best oxygen barrier materials commonly used in flexible packaging, but it loses barrier performance when wet, which is why it's almost always sandwiched between moisture-blocking layers rather than used alone. Metallized film, a thin vacuum-deposited aluminum layer on a polymer substrate, and true foil laminations offer strong oxygen and light barrier at a lower cost than EVOH structures, at the tradeoff of losing microwave compatibility and, with foil, the ability to see the product through the package.
Polyolefins, PE and PP, are naturally good moisture barriers but poor oxygen barriers, which is the opposite profile from EVOH. This is why moisture-sensitive, oxygen-sensitive products (many edibles and some cosmetic formulas) need a structure combining both barrier types rather than relying on one material to do both jobs.
Over-specifying barrier film, using a high-barrier EVOH or foil structure on a product that doesn't need it, adds real cost without a corresponding benefit. Under-specifying it shows up as product degradation, staleness, color shift, potency loss for cannabinoid products, well before the printed best-by date. The right call depends on the specific product's oxygen and moisture sensitivity, not a default "premium equals foil" assumption.
We spec film structure to the product's actual sensitivity profile and required shelf life, not a one-size-fits-all laminate. For format decisions that pair with barrier film selection, see Stand-Up Pouches vs. Flat Bags.
See our flexible packaging capabilities.