Multilayer Method: the addition of a plastic film was the initial step to make brick containers impermeable to liquids and heat-sealable. Within the sixties, an aluminum foil started to be added on the cardboard container to make certain much better safety and extend the shelf life of the packaged solution. https://gablecarton.video.blog/2025/04/09/why-gable-top-packaging-is-taking-over-modern-sustainable-markets/