Multilayer procedure: the addition of the plastic film was the first step to make brick containers impermeable to liquids and warmth-sealable. While in the 1960s, an aluminum foil began to be additional towards the cardboard container to be certain superior safety and lengthen the shelf lifetime of the packaged merchandise. https://sustainablesoappackaging.blogspot.com/2025/08/sustainable-liquid-packaging-smart.html