Multilayer method: the addition of the plastic movie was the initial step to generate brick containers impermeable to liquids and heat-sealable. From the sixties, an aluminum foil began to be included on the cardboard container to make sure much better protection and prolong the shelf life of the packaged merchandise. https://leak-proofgabletopcarton.blogspot.com/2025/02/gable-cartons-future-of-packaging.html