EP0654418A1

EP0654418A1 - Inflated, self standing flexible pouch

Info

Publication number: EP0654418A1
Application number: EP93203170A
Authority: EP
Inventors: Patrick Jean-François Etesse; Werner Herman Marie Bert Libens
Original assignee: Procter and Gamble Co
Current assignee: Procter and Gamble Co
Priority date: 1993-11-15
Filing date: 1993-11-15
Publication date: 1995-05-24
Also published as: JPH09505260A; WO1995013971A1

Abstract

Self-standing pouches are disclosed which are made of a flexible material, which comprise a contained goods and which are inflated during manufacture, before they are closed. Inflated pouches are thus obtained which are made of a flexible material and which are yet substantially more rigid than similar but non-inflated pouches. The pouches thus obtained stand upright in a stable manner and are less prone to folding. In a preferred embodiment, the pouches herein comprise a cut-opening region, and a spontaneous pouring spout is formed as the cut-open region is cut off.

Description

Technical field

The present invention relates to doypack-type pouches, i.e. self-standing pouches made of flexible material.

Background

Doypack-type pouches are well known in the art. These self standing pouches have found wide commercial applications because they are environmentally compatible in that they generate much less waste material and volume than conventional packaging. Indeed, these pouches are made with flexible materials such that the pouch can be rolled after it is used, and disposed of in a convenient manner. Most of the doypack business thus lies in refill packaging. Another main feature of doypack-type pouches is that they comprise a base design such that they are self-standing, thus they can be conveniently displayed on shelves, and securely stored in the household.
To maximize the environmental benefit obtained with doypack-type pouches, it is desirable to use materials which are as thin as possible. However, this requirement is somewhat in contradiction with the requirement that the pouches should be self-standing. Indeed, as the material used gets thinner, the pouch tends to fold, especially in the headspace region. This is clearly undesirable as folding compromises stability of standing, and can even lead, in the worst conditions, to cracking of the pouch in the folded region. A possible solution to this problem is the elaboration of pouches with sophisticated and specific dimensions or design for a given volume. This solution involves a certain amount of research and is therefore impractical, expensive and inflexible as different designs are required for different volumes.
Another problem which is also somewhat linked to the material used, specifically its thickness, is that the pouches thus produced may be difficult to open. Indeed, most preferred doypack-type pouches have a cut-open region, generally in an upper corner. This region must be cut off, and the contained goods can be dispensed from that region. However, it often occurs that the side walls of the pouch in the opening region remain closely one against the other so that they must be separated before the contained goods can be dispensed. This problem is even more acute when thinner materials are used and it becomes more difficult to grab one of the side walls only to separate it from the other.
The present invention solves both these problems at the same time. Indeed, we have now found that by inflating a doypack-type pouch before it is closed, an inflated pouch is obtained which is less prone to folding and wherein the formation of a spontaneous spout is eased as the cut-opening region is cut off. This invention is also very flexible in that it can apply to any pouch, by adjusting the amount of air to be introduced in the pouch.

Summary of the Invention

The pouches of the present invention are self-standing pouches made of a flexible material and comprising contained goods, characterized in that they are inflated. The present invention also encompasses a process for the manufacture of such pouches, wherein said pouches are assembled leaving their filling regions opened, and the pouches are then filled with said goods and inflated before they are closed.

Detailed Description of the Invention

The pouches of the present invention are doypack-type pouches. By doypack-type pouch, it is meant herein a pouch which is made of a flexible material and which has the ability to stand in an upright position.
Such pouches are disclosed for instance in US 3,380,646, L. Doyen et Al. In their most generic description, these pouches comprise a base portion, on which the pouch stands, and an upper portion. The pouches generally comprise two opposite side walls and a bottom gusset comprising two panels joined by a median line. The panels of the bottom gusset are affixed to the side walls in the bottom region of the pouch, constituting said base portion, and the side walls are affixed together in the upper part of the pouch, distant from the bottom region. Various embodiments of the base are conceivable. In '646, the panels of the gusset and the respective side walls are assembled together along a curved seal, and the panels are assembled together along their vertical edges, in the standing pouch. In our co-pending European application 93870118, we described a major improvement, which is a preferred embodiment herein, where the panels are not assembled together along their vertical edges, and the panels of the gusset are assembled with their respective side walls along oblique instead of vertical seals. This improvement provides already greater standing stability.
The pouches herein have dispensing means. Dispensing means may include all kinds of caps, which can be affixed via a transition piece to a side wall of the pouch, but preferably, the pouches herein are opened by cutting a portion of the pouch, said portion hereinafter referred to as a cut-open region. Said region is preferably an upper corner of the pouch so as to provide a pouring spout upon opening. Said region is generally at least materialized by a printed indication on the side wall, but it may also be further materialized by at least one line of greater weakness, preferably one on each side wall, made for instance of a thinner material, or a different material, or a partially preperforated material. Furthermore, said line of weakness can comprise a notch or a slit which assists in starting tearing the pouch along said line.
The pouches herein are made of a sheet-like flexible material. By flexible, it is meant herein a material such that the pouch can be rolled or folded before it is disposed of. The suitable material to be used further depends on the goods to be contained in the pouch. Suitable goods to be contained in the pouches herein include granular and liquid materials. Particularly In the case where liquid goods are to be contained, it is generally suitable to use predominantly thermoplastic materials. A great variety of such materials have been disclosed in the art, including various polyethylenes, polyamides, polycarbonates, polyester polyvinylidene chloride, nylons, polyolefins polyvinyl chlorides etc.., and mixtures thereof. It is a general object of the present invention to use materials which are as thin as possible. Accordingly, sheet-like thermoplastic materials having a thickness of from 10 to 500 micrometers, preferably 100 to 250, are suitable to manufacture pouches having an internal volume of at least 5 liters.
The pouches of the present invention are inflated before they are closed. Pouches according to the present invention differ from conventional pouches in that the headspace folds substantially less, or not at all, and the side walls in the headspace tend not to be in contact one with the other, except for the sealing lines. In the preferred pouches according to the present invention, the side walls only come in contact at the sealing lines on the entire pouch.
The pouches of the present invention thus appear stiffer, and are more stable. This stiffening effect, which is particularly effective in the headspace portion of the pouch, can be further supported in the lower region of the pouch by providing substantially vertical ridges on the side walls of the standing pouch, as described in our co-pending European application 93870118. Preferably these stiffening ridges extend from the bottom edge of the pouch up to the headspace. In the preferred embodiment where the panels of the gusset are assembled with their respective side walls along oblique instead of vertical seals, the stiffening ridges extend from the lowest points of said oblique seals up to the headspace.
Furthermore, because the gas inside the pouch prevents the side walls from being in contact, the formation of a spontaneous pouring spout is eased as the cut-open region is cut off. This effect is enhanced as the amount of gas inside the pouch increases. If the amount of gas inside the pouch exceeds atmospheric pressure, there will even be a gas outflow as the cut-open region is cut off, further favoring the formation of a spontaneous pouring spout. The formation of a spontaneous pouring spout can be further favored as disclosed in our co-pending European application 93870119, by providing further ridges which extend in the cut-open region on the side walls of the pouch. Preferably said ridges extend outwardly, and at least one ridge is provided on each side wall, and the ridges on the side walls correspond one with the other.
The amount of gas to be introduced in the pouch depends, amongst other things, on the dimensions of the pouch, how much it is filled, and the degree of stiffening and ease-of-pouring which is desired. In all cases it can be determined by simple trial and error. It is preferred to inflate enough gas so that the walls of the pouch only come in contact at their sealing lines. Also, the gas which is used to inflate the pouch may vary, depending mainly on the packaging material and the goods to be contained. The most economical and safe embodiment is to use atmospheric air.
Generally, the pouches according to the invention can be manufactured by assembling all of the pouch except a filling region, generally the top portion of the pouch, in a gas-tight manner. Then, the pouch is filled with the goods it is to contain and it is inflated with the appropriate amount of gas. Inflation may occur while the pouch is being filled, or preferably after it is filled, before it is closed in a gas tight manner. In the typical manufacture of such pouches, one of the last step is the closing of the last portion of the pouch, the upper portion, after the pouch is filled. In the case where the pouch is made of a thermoplastic material, closing means are usually heated jaws which grab and heat seal the side walls of the pouch at their top edges. This state of the art equipment can be easily modified by adding a gas pipe in the region of said jaws, e.g. about in between said jaws, and by synchronizing gas inlet with the action of the jaws.

Example

A pouch is made which is 250mm wide, 235 mm height and which has a gusset of 50mm. The material used is a laminate comprising a 190 micrometers layer of polyethylene and a 12 micrometers layer of polyethylene terephthalate. The pouch is assembled in a conventional manner, i.e. all seals are formed except for the top seal. 2 liters of a liquid detergent composition are then introduced in the pouch. In a pre-sealing operation, the top edge of the pouch is stretched and about 0.3 Liters of air are introduced by means of an air nozzle while the top edge of the pouch is being sealed around the nozzle. The seal is strengthened and completed in a final sealing operation after the nozzle has been removed.

Claims

A self-standing pouch made of a flexible material and comprising a contained goods, characterized in that said pouch is inflated.
A pouch according to claim 1 wherein said goods is a liquid detergent composition.
A pouch according to the preceding claims which further comprises substantially vertical stiffening ridges.
A pouch according to the preceding claims, which comprises an cut-opening region.
A pouch according to claim 4, and which further comprises ridges which extend into said opening region.
A pouch according to the preceding claims which is made of a flexible sheet material comprising a thermoplastic material.
A pouch according to claim 6 wherein said material has a thickness of from 10 micrometers to 500 micrometers, preferably 100 micrometers to 250 micrometers.
A process for making a pouch according to the preceding claims wherein said pouch is assembled, leaving open a filling region, and said pouch is filled with said goods and inflated before it is closed.
A process according to claim 8 wherein said pouch is inflated after it is filled.
A process according to claim 8 wherein said pouch is inflated while it is being filled.