Multilayer System: the addition of the plastic film was the initial step to help make brick containers impermeable to liquids and warmth-sealable. During the 1960s, an aluminum foil started to be added to your cardboard container to be certain better protection and increase the shelf lifetime of the packaged item. https://gabletoppak.politics.blog/2025/02/25/gable-top-pak-crafting-a-sustainable-legacy-with-every-pak/