Multilayer program: the addition of the plastic film was the initial step for making brick containers impermeable to liquids and heat-sealable. In the sixties, an aluminum foil started to be added on the cardboard container to ensure far better safety and extend the shelf life of the packaged product. This https://wateringabletoppak.wordpress.com/2025/09/24/water-in-carton-packaging-preserving-nature-one-sip-at-a-time/