Multilayer method: the addition of the plastic film was the initial step to help make brick containers impermeable to liquids and heat-sealable. In the nineteen sixties, an aluminum foil began to be extra for the cardboard container to be certain greater defense and increase the shelf life of the packaged https://ecofriendlypackagings.blogspot.com/2025/08/how-water-in-sustainable-pak-is.html