Multilayer process: the addition of a plastic film was the first step to make brick containers impermeable to liquids and heat-sealable. Inside the sixties, an aluminum foil started to be extra to the cardboard container to make sure greater protection and increase the shelf lifetime of the packaged solution. Taking https://www.tumblr.com/gabletoppak/761384337533026304/gabletop-pak-source-for-premium-gable-top-cartons?source=share