Patent Description:
One desirable feature of such a flap is that, once opened, it falls under its own weight so that it lies folded away from the opening and does not interfere with the wipes being removed. A design that aims to provide a reliable hinge is shown in <CIT> by Prime Label & Screen, Inc. Here a resealable label flap is made of two main layers, a thicker base layer <NUM> and a top layer <NUM>, in the form of a rectangle. In practice, the base layer may itself be made of two or more layers, for instance to ease the application of the resealable adhesive. The rectangle is cut around three edges inside its circumference to form a flap portion, the fourth end forming a hinge. This hinge is constituted by slitting the lower layer but not the upper layer, so that the flap portion hinges about the upper layer where it bridges the slit. The region of the rectangle outside the cut forms a frame which remains stuck to the package.

In practice it is not easy to handle the assembly after the subsequent cut has been made through both layers so as to define the outline of the flap portion. The present invention aims to provide a flap that is easier to manufacture and also more reliable.

Another construction, using composite layers and intending to solve the problem of the flap undesirably returning to cover the opening while one is trying to extract a wipe, is shown in <CIT>. The flap is formed by two main layers, a thinner layer on top of a thick layer, the thin layer extending beyond one side of the lower layer and being fixed to the package by a strong adhesive. The construction appears not to solve the problem of the flap flipping back, because a transverse slit is formed in the upper layer over most of its transverse extent, so as to weaken the restoring force.

In a first aspect that is not part of the present invention there is described a resealable flap device in the form of a sheet for applying to or incorporating in packaging, comprising:.

Because the region of the flap portion behind the hinge line has only the single lower layer, the lower layer at that line, or in its vicinity, forms the desired hinge, being much less stiff - say two to ten times - than the composite of the two layers, in terms of Young's Modulus.

In general, the upper layer in the frame portion (i.e. the outside region surrounding the flap portion) will also end approximately in line with the hinge, though it may extend beyond it to a greater or lesser extent for added stability.

A tab may be formed on the end of the flap portion remote from the hinge in the usual way, to make it easier for the user to lift the flap. Preferably there is no adhesive on the underside of the tab, or any adhesive present is covered or neutralised, but the remainder of the flap portion generally has a tacky adhesive for resealable sticking to the package.

The lower layer may be of a tough but flexible polymer such as polypropylene (PP), about <NUM> thick, the upper layer of the same or, preferably, a different material, such as polystyrene (PS) or PET, and preferably at least two or three times as thick, preferably at least <NUM> thick. The two are laminated using a suitable adhesive such as acrylic-based adhesive, and the reclosure adhesive under the base layer can be any usual adhesive for this purpose.

The flap may be generally rectangular, rounded, elliptical, oval or ogival in shape, though the hinge will generally be a straight line. The "north-south" direction of the flap, i.e. the direction in the plane in which the flap opens and closes, will be termed the "longitudinal" direction, the perpendicular direction in the plane of the flap (when closed) being termed "transverse". The "front" of the flap is that edge or end picked up by the user to open the flap.

The present invention is directed to a resealable flap device according to claim <NUM>. This flap is in the form of a sheet for applying to or incorporating in packaging and comprises a layer of flexible material, the layer being cut through to outline a flap portion, but leaving an edge uncut in a hinge region, forming the rear end of the flap; wherein the layer continues rearwardly and incorporates a second flap portion with a second hinge region and having a slot by which a product may be suspended when the flap device is fixed to the packaging.

The device is easy to manufacture because the upper layer can be formed by selective removal of parts of the upper layer to form the hinge region. This can be done, for instance, by cutting through the upper layer only and then removing the unwanted portion of the upper layer. In addition, printing a blocking agent to prevent adhesion between base and upper layers in certain areas may be helpful. Also, although the top surface of the laminate is not entirely smooth (because of the local absence of the top layer at the base of the hinge), this presents no practical (nor aesthetic) difficulty and it does not interfere with manufacture of the flap device itself, nor with assembly as it is applied to the pack.

It is to be understood that the upper and/or lower layers may be printed upon, for example for the purpose of colouring or shading the device, or to apply a logo or graphic or other printed material such as instructions or advertising material.

Print may be applied to one or both of an upper and lower side of the lower layer, and/or to one or both of an upper and lower side of the upper layer. Print may be applied before adhesive is applied to a layer, in which case the presence of the print typically does not adversely affect subsequent bonding of the layer to another surface. Alternatively print may be applied to all or a selected portion of an area of a surface of the upper or lower layers after a layer of adhesive has been applied to the surface. The presence of the layer of print on the adhesive essentially reduces or inhibits substantially entirely the ability of the adhesive in that area to cause the layer to stick to a surface that is subsequently brought into contact with the printed area.

This feature may be useful in some embodiments. For example, in embodiments having a tab formed on the end of the flap portion remote from the hinge, to make it easier for the user to lift the flap as described above, adhesive applied to the lower surface of the lower layer in order to allow the lower layer to be bonded to packaging may be printed upon in the region of the tab in order to prevent the tab from sticking to the packaging.

It is to be understood that, in addition or instead, the lower surface of the lower layer may be printed upon before adhesive is applied to that layer. In that case, it is typically the case that the adhesive will permit the printed (and any non-printed) regions of the lower layer to be bonded to the packaging to which the device is applied.

In addition or instead, the upper surface of the lower layer may be printed upon. In the case that a layer of adhesive is applied to the upper surface of the lower layer after printing upon the upper surface, the upper layer may subsequently be bonded to the lower layer even in regions in which print has been applied to the lower layer. However, if it is desired not to allow bonding of the upper and lower layers in certain regions, print may be applied to the adhesive after it has been applied to the upper surface of the lower layer or lower surface of the upper layer, to prevent adhesion in the printed areas.

If the upper and lower layers are both transparent, printed material on the lower layer or lower surface of the upper layer will be visible through the upper layer, and lower layer in the case of printing on the lower surface of the lower layer.

For a better understanding of the invention, embodiments will now be described with reference to the attached drawings, in which:.

<FIG> shows a composite picture of three different versions of flap devices or "label flaps" in accordance with a first aspect that is not part of the invention, before their application to the packaging for which they are destined. That is, they are still mounted on a release or backing layer <NUM>. All have the same basic features. The individual label flaps or flap devices <NUM> are arranged in rows on a release layer <NUM>. Each has a generally rectangular shape, out of which, by a cut <NUM>, is cut a flap portion <NUM>, leaving a surrounding frame <NUM>, which is in fact composed of two pieces each of a "mutton chop" shape.

The cut extends only over three sides of the rectangle, leaving a hinge <NUM>, forming the rear end of the flap in the longitudinal direction, i.e. the direction in which the flap is opened and closed. At the side or front end opposite the hinge is a protruding nose acting as a tab <NUM> when the device is in use.

The label flap is in two main layers, though other layers, such as adhesives, may be present also. The lower layer is present over all the area of the label flap as shown, while the upper layer of the flap portion, in accordance with the invention, is not present behind or beyond the hinge - in the upper region of the drawing as presented, forming a single-layer rear region <NUM>, which is to remain attached to the package.

It may be noted that hinge line <NUM> of each flap is in the direction of feed of the roll on which the laminate materials are handled. As is known, a laminate material when released from the roll has a tendency to curl in the circumferential direction of the roll. In some known types of flap this can lead to the flap tending to reclose rather than stay open; the design shown does not suffer from this defect. It may further be noted that in this embodiment the flap is wider than long, further reducing any tendency to curl in the longitudinal direction.

This relationship is evident from the very schematic <FIG> where a flap device is removed from the release film and applied to a package. <FIG> shows a section along the dogleg line <NUM>-<NUM> in <FIG>. Here the lower <NUM> and upper <NUM> layers are visible. The upper layer <NUM> is generally thicker, in this embodiment <NUM> thick, and made of PET. This material has excellent rigidity properties: that is, it retains its flat shape after repeated uses. It adheres to the <NUM>-thick lower layer <NUM> of PP over most of its extent, including either side of the cut <NUM>, which passes through both layers at <NUM> and <NUM> respectively. Only in the region beyond the hinge is the label flap formed by the lower layer <NUM> only. This means that the cut-out flap portion <NUM>, consisting of both upper and lower layers, is free to pivot about the weaker single-layer hinge region <NUM>. Moreover, it is found that the flap, once opened, will lie back against the packaging and after use is easy to close again.

Also shown in <FIG>, though in dashed lines only, is the foil <NUM> of the package to which the label flap is applied. To this end the lower layer <NUM> has a layer of adhesive on its underside, not shown. As can be seen, the flap <NUM> covers the hole <NUM> from which moist wipes, or other contents, are to be extracted, while the hinge <NUM> is a short distance to the side of the hole. In fact, the hole will usually be made by the user on first use of the package, the outline of the hole being defined by a weak perforation which is then torn open by the attachment of the foil to the flap portion, as shown.

<FIG> is a cross-sectional view of a flap device <NUM> with the flap <NUM> in the open condition, leaving the frame <NUM> in place. The drawing is likewise very schematic and does not represent actual thicknesses. <FIG> is a corresponding 3D view showing the flap applied to the foil <NUM> of a package containing moist wipes. The contents of the package are accessed through the hole or aperture <NUM> formed in the foil <NUM> that forms a wall of the package.

Returning to <FIG>, further advantageous features may be noted. First, at two points along the cut <NUM> defining the flap, the cut is interrupted to form small ties <NUM>. These keep the frame and flap portion together after the flap assembly is removed from the release layer and before it is applied to the package. They can, however, be easily broken by the user on first use of the flap, and they also act as a tamper-check mechanism.

Secondly, the cut <NUM>, which passes through both layers to form the flap portion <NUM>, is also present in the lower layer for a short distance past the point where the upper layer stops. It can be seen that on each side of the flap, or near each end of the hinge <NUM>, a tightly curved cut <NUM> continues, curving round with a radius of a few mm, starting from the transversely directed line at the rear end of the cut that forms the flap. The cut goes first toward the rear edge (upper in the diagram), then outwardly towards the side edge, then slightly back towards the tab (front) edge. It is known as a "peel break" and its function is to stop a tear in the lower layer if the user opens the flap <NUM> too enthusiastically: in these circumstances the tear is directed round and does not continue to the rear edge of the lower layer (which would lift the flap off entirely). The peel break construction also has the advantage that a short strip of the lower-layer-only area lifts up and contributes to the flexibility of the hinge.

In use, the user takes hold of the tab <NUM>, which has no adhesive or where the effect of the adhesive is nullified, and pulls it up. This pulling force overcomes the tacky adhesive between the lower layer <NUM> and the package, though not at the area defined by perforations in the package, where instead the flap lifts the area to form the hole <NUM>. The ties <NUM> between flap and frame are also broken.

The opening action continues until the flap has lifted along the entire cut line shown as a thick line in <FIG>. The curve towards the rear, away from the hinge line, enables the hinge region <NUM> of the flap to lift from the substrate and form a tube of the material of the lower layer, having a relatively large radius, i.e. several times (at least twice) the thickness of the layer. This tube is visible from the side in <FIG>. Theoretically the cut could be a score that tears on first use. This large radius allows the flap to lie back with only a very small restoring force, much less than the weight of the flap.

The continuing cuts <NUM> could in theory just go straight back towards the rear edge, but it is better if they curve round as described above, to mitigate the risk of tearing though the entire flap device. The longitudinal extent of the curve might be, say, a third to a half of the longitudinal extent of the flap device behind the flap proper.

To make the laminate flap device, the lower layer has an adhesive-blocking layer applied over the hinge/rear area <NUM>; such a blocking layer may also be applied to the underside of the tab area <NUM> of the upper layer. Adhesive is then spread over the lower layer and the upper layer is stuck to the lower. A first cut, through the top layer only, is made along the hinge line (and the ends of the frame <NUM>) and the resulting separated rear part of the top layer (uppermost in <FIG>) is removed. The flap/frame shape is then cut through both layers, along with the peel breaks. When ready, the flap device is removed from the backing and applied to a package.

The variations shown in <FIG> will be explained as follows. The top row shows flap portions rounded at the base (i.e. near the hinge <NUM>), the frame continuing for a short distance to surround the flap portion, but not as far as the edge of the lower layer - in fact about the same distance as, or slightly more than, the rearward extent of the curved cut <NUM>. The middle row shows a version where the base of the flap is square, with the peel breaks starting some way in along this base; the cut in the lower layer therefore extends some way in along the hinge line towards the centre. In this version, unlike the first, the frame does not continue towards the rear edge of the lower layer beyond the line of the hinge <NUM>. In the third row the curved cut <NUM> continues in the lower layer past the square end <NUM> of the upper layer, so that one could say the hinge is distributed over a certain longitudinal extent of the single-layer portion <NUM>.

<FIG> shows a variant, illustrating the presently claimed invention, in which the rear region <NUM>' of the flap device extends further back in the longitudinal direction, forming a rear section <NUM>, and a second flap-type area <NUM>' formed by retaining a portion of the upper layer <NUM>. The flap is defined by a similar cut <NUM>' through both layers, with the tear-stop curves <NUM>' and hinge region <NUM>' back-to-back, as it were, with that of the package flap <NUM>, and has an adhesive-free tab <NUM>'. It is somewhat more squat in shape than the flap proper <NUM>, and in addition the flap part <NUM>' has a transverse slot <NUM>. This slot, known as a "Euroslot", is used for hanging the package when the closure device has been applied to a package. The upper layer used for the hanging portion will probably be a portion of the same layer as is used for the flap, but it could be formed separately. The slot could of course have a different shape, or just be a simple hole or even a hook.

<FIG> shows a perspective view of the label flap applied to a package, and with the flap <NUM> and the hanger flap <NUM>' both deployed. This is how the package would appear in use. In a shop the flap <NUM> would be shut but the package would be suspended by the hanger flap <NUM>'.

In accordance with further aspects of the invention, the integral hanger flap does not have to have the same layer construction as here shown, but could have the layers inverted, or a weakness formed for the hinge line or lines in a different way, such as by partial cutting or scoring.

<FIG> shows some schematic sections illustrating the upper and lower layers <NUM>, <NUM> as before, but also the adhesive layers <NUM>. One adhesive layer <NUM> sticks together the upper and lower layers of the label flap, and the other sticks the label flap to the package <NUM>. They can be the same or different adhesives. Diagrams (a) and (b) show the manufacturing step where the section <NUM>' of upper layer <NUM> is removed, following the cutting step forming the outline of the flap <NUM> and enabled by the presence of a silicone release layer <NUM>. This leaves the single-layer area <NUM> of the label flap, including the hinge regions for the flap <NUM> and hanger flap <NUM>'. (The package <NUM> is also shown, though it would not actually be present during the manufacturing process). The adhesive-kill layers <NUM> underneath the tabs <NUM> and <NUM>' are also visible. Diagrams (c) and (d) show the label flap in use undeployed and deployed.

<FIG> shows a plan view, separated into the component layers, of the embodiment of <FIG>. This shows how the silicone release layer <NUM> corresponds to the shape of the cut and removed portions <NUM>' of the upper layer.

Finally, <FIG> shows a typical sequence of steps in the manufacturing process. First, the roll of backing layer and lower layer (with its layer of adhesive) is fed and the two layers are separated. The adhesive kill layer <NUM> is applied to the lower layer (Step S1). Then the lower layer is reunited with the backing and the laminate turned over (S2). The silicone release coating <NUM> is then printed on the base or lower layer <NUM>, with any logos etc. (S3, S4). Then the stiff top layer <NUM> is laminated onto the lower layer at step S5. The hinge/rear area <NUM> is cut out and removed, and any final print applied (S6, S7). Finally the flap outline is cut, including the tear stops <NUM> and the tab <NUM>. The individual flap devices can then be applied to packages as required.

It will be appreciated that, while the embodiments described are envisaged for moist wipes, they could be applied to any packaging where a sealing flap is required.

Claim 1:
A resealable flap device in the form of a sheet for applying to or incorporating in packaging comprising a layer construction of flexible material, the layer construction being cut through to outline a flap portion (<NUM>), but leaving an edge uncut in a hinge region (<NUM>), forming the rear end of the flap;
characterised in that the layer continues rearwardly and incorporates a second flap portion (<NUM>') with a second hinge region (<NUM>') and having a slot (<NUM>) by which a product may be suspended when the flap device is fixed to the packaging.