Multilayer System: the addition of the plastic film was the initial step to create brick containers impermeable to liquids and heat-sealable. During the sixties, an aluminum foil began to be additional for the cardboard container to be sure far better defense and increase the shelf life of the packaged product. https://wateringabletop.tech.blog/2025/06/09/gable-top-milk-carton-a-smarter-sip-towards-a-greener-future/