Multilayer Technique: the addition of the plastic film was step one to produce brick containers impermeable to liquids and heat-sealable. From the nineteen sixties, an aluminum foil started to be included on the cardboard container to be sure much better safety and lengthen the shelf life of the packaged item. https://gabletop-pak.mystrikingly.com/blog/the-rise-of-gable-cartons-in-the-packaging-industry