Multilayer Method: the addition of a plastic film was the initial step for making brick containers impermeable to liquids and heat-sealable. From the 1960s, an aluminum foil started to be added on the cardboard container to be sure better safety and lengthen the shelf lifetime of the packaged products. Now https://gablecarton.game.blog/2024/10/05/sustainable-packaging-gable-top-cartons-as-a-game-changer/