Multilayer Technique: the addition of a plastic movie was the initial step to make brick containers impermeable to liquids and heat-sealable. While in the 1960s, an aluminum foil started to be added to your cardboard container to make sure much better protection and increase the shelf life of the packaged https://share.evernote.com/note/50a43c45-be13-328c-5d6a-78a96bc30d4c