Multilayer program: the addition of a plastic film was the first step to produce brick containers impermeable to liquids and heat-sealable. Inside the 1960s, an aluminum foil started to be added to the cardboard container to make sure much better protection and extend the shelf lifetime of the packaged products. https://dairycartonsustainability.water.blog/2025/02/07/innovative-eco-friendly-packaging-solutions-for-a-sustainable-future/