Multilayer System: the addition of the plastic film was step one to make brick containers impermeable to liquids and heat-sealable. While in the 1960s, an aluminum foil began to be added towards the cardboard container to make sure improved safety and prolong the shelf lifetime of the packaged product. This https://wateringabletoppak.wordpress.com/2025/09/24/water-in-carton-packaging-preserving-nature-one-sip-at-a-time/