Multilayer process: the addition of the plastic film was the initial step for making brick containers impermeable to liquids and heat-sealable. In the nineteen sixties, an aluminum foil began to be additional towards the cardboard container to be sure improved protection and extend the shelf life of the packaged product. https://waterinsustainablepak.news.blog/2025/09/24/water-in-carton-packaging-preserving-nature-one-sip-at-a-time/