GB2264690A

GB2264690A - Gusseted carrier bags

Info

Publication number: GB2264690A
Application number: GB9204899A
Authority: GB
Inventors: John Madeley
Original assignee: Individual
Current assignee: Individual
Priority date: 1992-03-06
Filing date: 1992-03-06
Publication date: 1993-09-08
Also published as: GB9204899D0

Abstract

A gusseted carrier bag 1 comprises first and second opposing faces interconnected along opposite side edges by means of gussets (7, figure 2), each face of the bag having side regions 9 accommodating the gussets and a central region 13 between the side regions. For greater strength, the material of the bag has a greater thickness in the central region 13 of each face than in the side regions 9 and gussets (7). A handle is formed by cut-out portions 15 in the central region 13 of each face in the region of the open end of the bag. The bags may be supplied in a continuous strip wound on a spool, individual bags being separable by perforations. <IMAGE>

Description

GUSSETED CARRIER BAG The present invention relates to a gusseted carrier bag, and more particularly is concerned with a gusseted carrier bag having side regions and a central region, the material of the central region having a greater thickness than the material of the side regions and gussets thereof.

Gusseted carrier bags, so-called vest-type carrier bags, are known and are made, for example, by taking a continuous tube of polyethylene plastics material having constant thickness, flattening the tube to form a gusset in opposite side regions of the tubular material, heat sealing the plastics material at the top and the bottom of the intended carrier bag to form a sealed blank, and cutting the sealed blank from the continuous tube of plastics material. The sealed blanks are then accumulated into a stack of a predetermined number, ensuring that the ends of the blanks are aligned, and a generally rectangular cut-out is made through the entire stack of blanks to form the desired carrier bags.It is necessary to ensure that the bags are accurately aligned and that the size of the cut-out is sufficient to extend into each gusset in order to provide a through-hole which forms the handles for the carrier bag.

Such a known gusseted carrier bag has considerable strength due to the provision of the handle in the gusseted region where there are four thicknesses of plastics material, but has the disadvantages that it is necessary to heat seal the bag both at the top and at the bottom and that it is necessary to accumulate and accurately align the blanks prior to forming the handle. This is a time-consuming and inconvenient operation compared with forming the handle as part of a continuous manufacturing operation.

It is therefore an object of the present invention to provide a gusseted carrier bag which is relatively strong, but which is capable of being manufactured in a continuous operation.

According to one aspect of the present invention there is provided a gusseted carrier bag comprising first and second opposing faces interconnected along opposite side edges by means of gussets, each face of the bag having side regions accommodating the gussets between the opposing faces and a central region between the side regions, the side regions and the central region extending from one end of the bag to the other, the first and second faces and the gussets being secured together in the region of one end of the bag so as to form a closed bottom for the bag, and a handle being formed by cut-out portions in the central region of each face in the region of the other, open, end of the bag, the material of the bag having a greater thickness in the central region of each face than in the side regions and gussets thereof.

The bag is preferably made of a plastics material such as a polyethylene plastics material. The closed bottom for the bag may be formed by heat sealing the first and second faces and the gussets.

The cut-out portions forming the handle may be C-shaped, circular, square, rectangular or kidney-shaped.

The thickness of the material of the bag in the central region may be up to twice the thickness of the material in the side regions and gussets.

According to another aspect of the present invention there is provided a continuous strip of gusseted carrier bags as hereinbefore defined, the bags being wound onto a spool and being separable by means of perforations.

For a better understanding of the present invention and to show more clearly how it may be carried into effect reference will now be made, by way of example, to the accompanying drawings in which: Figure 1 is an elevational view of one embodiment of a gusseted carrier bag according to the present invention; and Figure 2 is a sectional view taken along the line II-II in Figure 1.

Figures 1 and 2 show a carrier bag 1 made from a continuous tube of plastics material, such as polyethylene. The tube of plastics material is folded flat so as to provide a first face 3 and a second face 5 interconnected by gussets 7 along opposing side regions 9 of the bag and extending, in use, from the bottom of the carrier bag to the open top thereof. The carrier bag 1 is sealed at the bottom with a heat seal 11 and is provided in central region 13 of the top of the bag with a cut-out handle 15 extending through both the first and second faces 3 and 5 respectively. In the illustrated embodiment, the cut-out handle 15 is substantially C-shaped, but alternative shapes include circular, square, rectangular, kidney-shaped and the like.

The carrier bags 1 according to the present invention are manufactured from a continuous tube of plastics material which is folded flat to provide continuous first and second faces interconnected by gussets 7 as shown in Figures 1 and 2. The tube is heat sealed, as at 11, at predetermined intervals to form the bottom of each bag 1 and a cut-out handle, as at 15, is formed at similar predetermined intervals. The continuously formed bags are then cut into individual bags 1 adjacent to each heat seal 11, so as to form an open top for each bag, for accumulating the bags into bundles and packing each bundle, for example, into a box.Alternatively, the continuously formed bags are perforated adjacent to each heat seal 11 and wound onto a spool as a continuous strip of bags 1 so that the bags can subsequently be unwound and torn off the continuous strip at the perforations so as to provide an open top for each bag. Advertising material or other matter can be printed onto the faces of the bags during the manufacturing process if required.

In order that the carrier bag 1 should be sufficiently strong, the plastics material in the central region of both the first and second faces 3 and 5 of the bag is thicker than the plastics material in the side regions 9 so as to provide a central reinforcing band for the bag. This can be seen in Figure 1 from the cross-hatched area in the central region of the bag and can be seen in Figure 2 by the use of a thicker line to denote the thicker material.

Clearly, the overall thickness of the plastics material is dependent on the intended use of the carrier bag, but in general, the thickness of the plastics material in the side regions 9 is of the order of 30 to 50 microns, while the thickness of the plastics material in the central region of the bag may be up to twice the thickness in the side regions. It may be disadvantageous for the thickness of the plastics material in the central region to exceed twice the thickness in the side regions since this would result in the central region of the bag having a greater overall thickness than the side regions which could give rise to a central high spot if the plastics material is wound onto a spool for example, leading to instability in the wound material.

I have found that such a carrier bag is strong in use because of the central reinforcing band which extends entirely around the bag from the top of one face 3 to the top of the other face 5. The central reinforcing band also incorporates the cut-out handle 15 thus ensuring that the bag does not fail prematurely in the region of the handle.

The manufacturing method for the carrier bags according to the present invention is particularly simple in that only a single heat sealing operation is required for the bottom of each bag, rather than heat sealing operations at both the bottom and the top of each bag as is required for conventional gusseted bags. Additionally, the cut-out handle can be formed as an in-line operation without the need to accumulate the bags into accurately aligned bundles and to cut out the handles as a separate batchwise operation as required for conventional gusseted carrier bags.

In addition to a more simple manufacturing method, the gusseted carrier bags according to the present invention have numerous practical and economic advantages over conventional gusseted carrier bags, for example: - the carrier bags according to the invention can be made shorter than conventional bags for an equivalent carrying capacity because of the different handle configuration, and this results in a lower material requirement for each bag; because it is no longer necessary to cut into the gusset in order to form the handle, the size of the gusset can be reduced and the size of the faces of the bag can be increased for the same size bag, and this gives a greater surface area for the faces of the bag and, in turn, allows a greater area of the bag to be printed and to bear, for example, advertising material;; the use of a thicker band of plastics material in the central region of the bags reduces the thickness differential between the side regions and the central region when the bags are folded flat, and this in turn leads to improvements in packaging the bags in that they lie more evenly in a box or on a spool than conventional carrier bags; the use of a thicker band of plastics material in the central region of the bags gives rise to a reinforcing band around the bags from one handle to the other, and thus the carrier bags according to the present invention are stronger than conventional carrier bags; and because only a single heat seal is required, as compared with two heat seals in conventional bags, the carrier bags according to the present invention are more reliable in use and are less likely to fail in the region of the heat seal.

Claims

1. A gusseted carrier bag comprising first and second opposing faces interconnected along opposite side edges by means of gussets, each face of the bag having side regions accommodating the gussets between the opposing faces and a central region between the side regions, the side regions and the central region extending from one end of the bag to the other, the first and second faces and the gussets being secured together in the region of one end of the bag so as to form a closed bottom for the bag, and a handle being formed by cut-out portions in the central region of each face in the region of the other, open, end of the bag, the material of the bag having a greater thickness in the central region of each face than in the side regions and gussets thereof.

2. A gusseted carrier bag as claimed in claim 1, wherein the bag is made of a plastics material.

3. A gusseted carrier bag as claimed in claim 2, wherein the bag is made of a polyethylene plastics material.

4. A gusseted carrier bag as claimed in claim 2 or 3, wherein the closed bottom for the bag is formed by heat sealing the first and second faces and the gussets.

5. A gusseted carrier bag as claimed in any preceding claim, wherein the cut-out portions forming the handle are C-shaped, circular, square, rectangular or kidney-shaped.

6. A gusseted carrier bag as claimed in any preceding claim, wherein the thickness of the material of the bag in the central region is up to twice the thickness of the material in the side regions and gussets.

7. A gusseted carrier bag substantially as hereinbefore described with reference to, and as shown in, the accompanying drawings.

8. A continuous strip of gusseted carrier bags as claimed in any preceding claim, the bags being wound onto a spool and being separable by means of perforations.