Integrally blow-moulded bag-in-container having interface vents opening to the atmosphere at location adjacent to bag's mouth; preform for making it; and processes for producing the preform and bag-in-container

Abstract

The invention is an integrally blow-moulded bag-in-container (2) and preform (1) for making it The bag-in-container (2) has an inner layer (21) forming the bag and an outer layer (22) forming the container, and a mouth (5) fluidly connecting the volume defined by the bag to the atmosphere. The container further has at least one interface vent (3) fluidly connecting the interface (14) between inner and outer layers to the atmosphere, wherein the at least one vent (3) runs parallel to the interface between inner and outer layers (21) (22) and opens to the atmosphere at a location (4) adjacent to, and oriented coaxially with the bag-in-container's mouth (5). Processes for manufacturing a preform and a bag-in-container as defined above are defined too.

Description

FIELD OF THE INVENTION [0001]The present invention relates in general to new developments in dispensing bag-in-containers and, in particular, to the interface vents design which allows control of the pressure at the interface between an inner layer (the bag) and an outer layer (the container) of said bag-in-container, in order to separate the inner layer from the outer layer and collapse the inner bag. It also relates to a method for producing said bag-in-containers and, in particular, to preforms used for their production, as well as a method for producing said preform.BACKGROUND OF THE INVENTION [0002]Bag-in-containers, also referred to as bag-in-bottles or bag-in-boxes depending on the geometry of the outer vessel, all terms considered herein as being comprised within the meaning of the term bag-in-container, are a family of liquid dispensing packaging consisting of an outer container comprising an opening to the atmosphere—the mouth—and which contains a collapsible inner bag joi...

AI Technical Summary

Benefits of technology

[0024]in a second stage, when the air pressure building up in said gap reaches a pr

Problems solved by technology

These types of bag-in-containers have the advantage of being reusable, but they are very expensive and labour-intensive to produce.

One redundant problem with integrally blow-moulded bag-in-containers is the formation of the interface vents.

This approach has of course the disadvantages that it involves an additional production step, and the danger of piercing the bag.

The venting holes described in EPA1356915 and U.S. Pat. No. 6,649,121, however, are not suitable for being connected to a source of pressurized gas to force delamination and squeezing of the inner bag.

It should be noted that the thickness of the preform's walls disclosed in JPA10180853 varies locally which can lead to serious processing and reproducibility problems of the final bag-in-container upon blow-moulding.

In the solutions proposed in the prior art relating to integrally blow-moulded bag-in-containers However, the vents run perpendicular to the interface and open to the atmosphere through a hole across, and normal to the outer container's wall, therefore providing no wedge effect and thus reducing the efficacy and reproducibility of the delamination of the inner bag from the outer container.

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