Multilayer procedure: the addition of the plastic film was the first step to produce brick containers impermeable to liquids and heat-sealable. Within the sixties, an aluminum foil began to be additional towards the cardboard container to make certain much better protection and increase the shelf lifetime of the packaged solution. https://gabletopcartonsforsoaps.blogspot.com/2025/10/liquid-soap-packaging-innovative-gable.html