Multilayer program: the addition of the plastic film was step one to help make brick containers impermeable to liquids and heat-sealable. From the 1960s, an aluminum foil started to be extra into the cardboard container to make sure far better safety and increase the shelf life of the packaged products. https://mineralwaterinbox.wordpress.com/2025/05/05/the-rise-of-gable-top-packaging-in-modern-beverage-and-dairy-industries/