ZA200902695B

ZA200902695B - Packaging pouches

Info

Publication number: ZA200902695B
Application number: ZA2009/02695A
Authority: ZA
Inventors: Nigel Ervine Claxton
Original assignee: Nigel Ervine Claxton
Priority date: 2008-01-31
Filing date: 2009-04-20
Publication date: 2009-12-30

Description

. Le 2 E2009 /02695

FIELD OF THE INVENTION

This invention relates to stand up pouches for containing small volumes of liquids, particularly liquid medicines.

BACKGROUND TO THE INVENTION

Rigid bottles blown or moulded from glass or synthetic resins are commonly used to pack small quantities of liquids, particularly medicines, reagents and colouring materials. In a production environment the handling of such bottles Co during labelling, filling and closing generally calls for the use of costly and complicated machinery. The bottles themselves, with their closures and labels, are commonly priced in such a way as often to be more costly than their contents.

In attempts to provide less costly containers for such liquids it has been proposed that the containers be formed from laminated or co-extruded sheet synthetic plastics material as so-called “stand-up” pouches. However these often ) require the use of costly labelling, erecting, filling and closing means for handling discrete pouches. It is common to provide such pouches with separate moulded shoulders, spouts and closures, which in turn demand the use of costly means to fasten the moulded elements to the sheet elements, either before or after filling.

It is an object of this invention to provide a method of manufacturing less expensive “stand-up” pouches than can be manufactured using known methods.

SUMMARY OF THE INVENTION

According to the present invention there is provided a method of producing pouches which comprises folding an advancing web of synthetic plastics material along three parallel lines thereby to form a gusset along one edge of the advancing web, forming transverse welds at intervals along the length of the web thereby to form individual | pouches, providing lines of weakening within the transversely extending boundaries of the transverse weld lines thereby to permit the

) | individual pouches to be detached from the web, and providing downwardly curving weld lines within the areas of the gussets, each curved weld line extending between two adjacent transverse weld lines. oo 5. ‘The method can include the step of welding the layers of material constituting the gusset to one another in the areas defined between the lower folds of the gusset, the curved weld lines and the transverse weld lines.

In a specific embodiment the method includes providing an L-shaped weld line extending from one of the transverse weld lines towards the other and then in the direction away from the gusset to the edge of the web thereby to define a filling and dispensing neck which is offset to one side of the centre line of the pouch.

In another embodiment, the method includes the step of providing two weld lines which extend towards one another from said transverse weld lines and then parallel to one another in the direction away from the gusset to the edge of the web to form a filling and dispensing neck which is centrally located on the centre line of the pouch.

To enable the pouch to be reclosed, after it has been opened, the method can include providing a rib and a groove which extend between said transverse weld lines and which enable the pouch to be reclosed by pressing the rib into the groove.

In embodiments where the pouch includes a neck, the rib and groove can extend across the neck.

Two or more parallel, spaced apart ribs and two or more parallel, oo spaced apart grooves can be provided. : :

The method can include the step of flattening and folding a tube of sheet synthetic plastics thereby to provide two spaced apart gussets extending in the direction of the length of the web, forming said transverse weld lines and said curved : weld lines, and splitting the flattened tube centrally thereby to form a row of pouches . on each side of the split line.

BRIEF DESCRIPTION OF THE DRAWINGS

For a better understanding of the present invention, and to show how the same may be carried into effect, the invention will now be described, by way of non-limiting examples, with reference to the accompanying drawings in which:

Figure 1 illustrates the folding of an elongate web;

Figure 2 illustrates the configuration of the web after folding;

Figure 3 illustrates the conversion of the folded web into pouches; : Figure 4 to 6 illustrate individual pouches and show the welds that are formed during the conversion of the web into pouches:

Figures 7, 8 and 9 illustrate various configurations that the mouth of the pouch may take; :

Figure 10 illustrates a pouch with a re-closable sealing structure, and:

Figure 11 illustrates two rows of pouches in a “two up” configuration. LT

DETAILED DESCRIPTION OF THE DRAWINGS

In Figures 1 and 2 the reference numeral 10 designates a multi-layered web of synthetic plastics material which is being drawn out from a reel 12. At the zones designated 14, 16 and 18 folds are formed in the advancing web by suitably positioned folding ploughs (not shown). The configuration of the folded web is best seen in Figure 2. An upper centre fold 20 and two lower outer folds 22, 24 provide a gusset 26 which-eventually forms the base of each pouch manufactured. : The folded web is advanced passed heat sealing stations at which the two layers 28 (see Figure 2) of the folded web above the gusset 26 and the four : layers constituting the gusset 26, are welded to one another.

Transverse welds 30 (see Figures 3 and 4) are formed at intervais along the length of the web. The welds 30 constitute the vertical edges of the pouches manufactured. Each weld 30 is bisected by a line of weakening 32. Each 5 line of weakening 32 is preferably constituted by perforations. The material between the pairs of pouches where the lines of weakness are introduced is sufficiently strong to allow the handling of formed pouches as a chain, thereby facilitating the printing and filling processes. The construction allows, when required, the individual pouches easily to be separated from the chain. :

Downwardly curving, curved weld lines 34 (see Figures 3 and 5) are formed within the areas of the gusset 26 and extend between the weld lines 30. The weld lines 34 do not have a sealing function but configure the gusset so that, in use, the gusset can serve as the base of the pouch. To provide additional stiffness the four layers of the gusset 26 can be welded to one another below the weld line 34 as indicated by the reference numerals 36. The weld lines 36 are not shown in Figures 4,50r71t009.

The pouch designated 38 and shown in Figure 7 has a mouth 40 which is formed by the juxtaposed edges 42 of the layers 28 of the web 10. The mouth 40 in this form extends the full width of the pouch.

In Figure 8 the two layers 28 of the web 10 are welded together along a weld line 44. A first part 44.1 of the weld line 44 extends parallel to the web’s edges and extends from one of the weld lines 30 towards the other weld line 30 and a second part 44.2 extends from the part 44.1 in the direction away from the gusset to the edge of the web 10. In this form the pouch’s mouth 46 is at the free end of a neck 48 which is narrower than the width of the pouch and offset from the pouch’s vertical centre line. The rectangular parts of the layers 28 which lie outwardly of the weld line 44 are removed to leave a shoulder to one side of the neck 48.

The pouch 38 shown in Figure 9 has a mouth 50 which is on the

- pouch’s centre line and defined by two L-shaped welds 52, 54 consisting of parts 52.1, 52.2, 54.1 and 54.2. The rectangular parts of the layers 28 outwardly of the L- “shaped weld lines 52, 54 are removed leaving a centrally positioned neck 56 with a . shoulder on each side thereof. Each weld line 52, 54 is configured in the same way asthe weld line 44.

Turning now to Figure 10, the pouch 38 illustrated has, just inwardly of the pouch mouth 46, two sets of ribs 58, 60. Each set of ribs comprises a first rib which has a groove extending in the direction of the length of the rib and a second rib which has an elongate protrusion which fits into, and interlocks with, the groove when the ribs are pressed together. The ribs 58, 60 provide the pouch with means which permit the pouch to be reclosed after being opened. The ribs 58, 60 are preferably extruded integrally with the web but can be in the form of ribbons which are attached to the web. : The neck 50 shown in Figure 9 can also be provided with rib sets 58, 60 as can the pouch 38 shown in Figure 7. .

If desired a single rib and a single groove can be provided.

The pouches illustrated in Figures 7, 8 and 9 are filled through the mouth 40 (Figure 7), through the mouth 48 (Figure 8) or through the mouth 50 (Figure 9). The mouths are then sealed closed. It is also possible, in the form of : Figure 8, to seal the mouth 46 and omit the weld line part 44.1. In this form the pouch is filled through the shoulder which is then sealed closed. In the form of Figure 9 one of the weld line parts 52.1, 54.1 can be omitted and the mouth 50 sealed closed. Filling is through the open shoulder.

To enable a high rate of production to be achieved, the web may have - 30 what is referred to as a “two up” configuration as illustrated in Figure 11. In this arrangement a flattened elongate tube is used and not a folded web. The reference numerals used in Figure 11 correspond to those used in the preceding Figures and particularly those used in Figure 8. The two rows of pouches formed are separated from one other along the line designated 62. The line 62 bisects the weld line parts. 44.2 and weld line parts 44.1.

When the pouches are made as described with reference to Figure 11, each pouch is open at the pouch mouth 46 (see Figures 8 and 10). They consequently have to be filled through the mouth 46. To provide a tamper evident feature the mouths 46 are then welded closed. A line of perforations can be provided between the sealed mouth 46 and the line 60 (Figure 10) to enable the end portion of the neck to be torn off.

It is also possible for the line 62 to lie alongside the weld line parts 44 1. This leaves all the necks 56 sealed closed and the shoulders open. In this form the pouch is filled through the shoulder which is then sealed closed. ’ The “two-up” configuration of Figure 11 can also be used to manufacture pouches having the configurations shown in Figures 7 and 9.

The pouch can contain a powder which has to be mixed with water or other liquid before use. To enable the correct amount of water to be added, a vertically elongate window 64 (Figure 3) can be provided in what is usually an opaque, printed face. The window thus extends parallel to the weld lines 30. The . window has a marker 66 next to it to indicate the correct filling level. | A one way valve (not shown) can be provided in the neck 48 and also in the neck 56 below the rib set 58. These valves permit liquid to flow from the main part of the pouch to the parts of the necks above the valves. These parts of the neck have a predetermined volume. Once these parts of the necks are filled, the ribs 58, 60 are separated to allow the liquid to be dispensed. The valves can comprise flaps of material which move apart when the pouch is inverted or squeezed and move together which the pouch is returned to its upright position or the squeezing pressure is removed.

Claims

HELE CLAIMS TT

1. A method of producing pouches which comprises folding an advancing web of synthetic plastics material along three parallel lines thereby to form a gusset along one edge of the advancing web, forming transverse welds at intervals along the length of the web thereby to form individual pouches, providing lines of weakening within the transversely extending boundaries of the transverse weld lines thereby to permit the individual pouches to be detached from the web, and providing downwardly curving weld lines within the areas of the gussets, each curved weld line extending between two adjacent transverse weld lines.

2. A method as claimed in claim 1, and including welding the layers of material constituting the gusset to one another in the areas defined between the lower folds of the gusset, the curved weld lines and the transverse weld lines.

3. A method as claimed in claim 1 or 2, and including the step of provided an L-shaped weld line extending from one of the transverse weld lines towards the other and then in the direction away from the gusset to the edge of the web thereby to define a filling and dispensing neck which is offset to one side of the centre line of the pouch.

4, A method as claimed in claim 1 or 2, and including the step of providing two weld lines which extend towards one another from said transverse weld lines and then parallel to.one another in the direction away from the gusset to the edge of the web to form a filling and dispensing neck which is centrally located . on the centre line of the pouch.

5. A method as claimed in claim 1 or 2 and including providing a rib and a groove which extend between said transverse weld lines and which enable the pouch to be reclosed by pressing the rib into the groove.

9 20 009/02695

6. A method as claimed in claim 3 or 4 and including providing a rib and a groove which extend across the neck and which enable the pouch to be reclosed by pressing the rib into the groove.

7. A method as claimed in claim 5 or 6 and including providing two or more parallel, spaced apart ribs and two or more parallel, spaced apart grooves.

8. A method as claimed in any preceding claim and including the step of flattening and folding a tube of sheet synthetic plastics thereby to provide two spaced apart gussets extending in the direction of the length of the web, forming said transverse weld lines and said curved weld lines, and splitting the flattened tube centrally thereby to form a row of pouches on each side of the split line.

9. A method as claimed in any preceding claim and comprising the step of providing the pouch with an opaque area within which area there is a transparent window which extends parallel to said transverse weld lines, there being a marker adjacent said window to indicate a filling level.

10. A method as claimed in claim 3, 4 or 6 and including providing a one way valve for controlling liquid flow into said neck from the remainder of the pouch.

11. A method of producing pouches substantially as hereinbefore described with reference to the accompanying drawings. Dated this 16" day of April 2009. rian Bacon & Associates Inc. Applicant's Patent Attorneys