container with inner bag

Abstract

The present invention relates to a container having an inner bag comprising a substantially rigid outer container and a readily deformable inner bag, wherein the outer container and the inner bag are constructed of different thermoplastic materials, the outer container and the inner bag are not welded to each other , the container has a container opening and at least one pressure equalization opening in the wall of the outer container for balancing the pressure in the gap between the outer container and the inner bag when the inner bag shrinks, wherein the microbody is integrated into the In the layer of the inner bag and / or in the layer of the outer container directed towards the inner bag, the material of the micro-bodies does not melt during the manufacture of the container, the micro-bodies produce relief on the surface of the layer.

Description

technical field [0001] The present invention relates to a container comprising a substantially rigid outer container and an easily deformable inner bag, wherein the outer container and the inner bag are constructed of different thermoplastic materials, the outer container and the inner bag are not welded to each other. The container comprises a container opening for the discharge of the contents of the container and at least one pressure equalization opening in the wall of the outer container for equalizing the pressure in the gap between the outer container and the inner bag when the inner bag contracts. The container can be manufactured by a co-extrusion process where by forming excess material at the base of a blow mold, the inner bag is sealed with a base weld seam that traps the also sealed base in the outer container in the weld seam. Such a container is disclosed, for example, in European patent EP0912420, which also shows how pressure equalization openings can be form...

AI Technical Summary

Problems solved by technology

However, the inner bag is usually separated from the outer container differently, and often only incompletely, on both sides of the base seam, so that it may happen that not all of the container contents can subsequently be drained

The high reduced pressure can also lead to a permanent deformation of the inner bag, so that the inner bag can no longer be applied flat to the outer container, forming wrinkles in the worst case