TONIOLO, Umberto (Propack GmbH, Boveristrasse 15, Ladenburg, 68526, DE)
WIEDEMANN, Ralf (Reckitt Benckiser Italia, Piazza S. Nicolo 12/3, Mira VE, 30034, IT)
ROSCIOLI, Laura (Reckitt Benckiser Italia, Piazza S. Nicolo 12/3, Mira VE, 30034, IT)
TONIOLO, Umberto (Propack GmbH, Boveristrasse 15, Ladenburg, 68526, DE)
WIEDEMANN, Ralf (Reckitt Benckiser Italia, Piazza S. Nicolo 12/3, Mira VE, 30034, IT)
RECKITT BENCKISER (UK) LIMITED (103-105 Bath Road, Slough, Berkshire SL1 3UH, GB)
| CLAIMS 1. A closure for a detergent container wherein the closure comprises a self-venting valve with an opening formed therein to permit the passage of gas there through; and a sheet secured to the closure for controlling the flow of gas through the opening, wherein the sheet of material has a first region secured to the closure in an area remote from the opening and a second region covering the opening, wherein the second region is only partially secured to the closure and a vent passage is defined between the unsecured portion of the second region and the closure, the vent passage extending from the opening towards the periphery of the sheet to permit controlled venting of gas from the opening. 2. A closure according to claim 1, wherein the sheet includes a strip which is non-adhesive. 3. A closure according to claim 2, wherein the sheet comprises two first regions arranged on opposite sides of the opening and a second region arranged between the two first regions. 4. A closure according to claim 1, 2 or 3, wherein the detergent composition comprises a component which degrades to produce a gas, e.g. an oxygen based bleach such as hydrogen peroxide or other bleach, such as a chlorine based bleach. 5. A detergent container comprising a closure, wherein the closure comprises a self-venting valve with an opening formed therein to permit the passage of gas there through; and a sheet secured to the closure for controlling the flow of gas through the opening, wherein the sheet of material has a first region secured to the closure in an area remote from the opening and a second region covering the opening, wherein the second region is only partially secured to the closure and a vent passage is defined between the unsecured portion of the second region and the closure, the vent passage extending from the opening towards the periphery of the sheet to permit controlled venting of gas from the opening. |
This invention relates to a self-venting cover for a cap for a detergent package.
Detergent products, especially liquids are generally sold in rigid containers that have a removable cap to allow release of the detergent liquid.
One problem with the use of such caps is that certain detergents contain compounds that degrade in storage to produce a gas. The production of this case can lead to swelling of the container and in severe cases can cause the container to burst. This problem is particularly prevalent at high temperatures and in cases where the detergent container is exposed to considerable disturbance in transport and storage.
It is an object of the present invention to obviate / alleviate the problem outlined above.
According to a first aspect of the invention there is provided a closure for a detergent container wherein the closure comprises a self-venting valve with at least one opening formed therein to permit the passage of gas there through; and a sheet secured to the closure for controlling the flow of gas through the opening, wherein the sheet of material has a first region secured to the closure in an area remote from the opening and a second region covering the opening, wherein the second region is only partially secured to the closure and a vent passage is defined between the unsecured portion of the second region and the closure, the vent passage extending from the opening towards the periphery of the sheet to permit controlled venting of gas from the opening.
Preferably, the sheet includes a strip which is non-adhesive. In this arrangement the sheet preferably comprises two first regions arranged on opposite sides of the opening and a second region arranged between the two first regions. The second region is intended to be placed over the opening. Such an arrangement is particularly easy to mass-produce because the non-adhesive strip and adjacent adhesive areas can be produced in the machine direction of the machine which is fabricating the cover.
In a preferred embodiment the opening is in the form of a circular hole formed in the production step of the closure or cut in the material of the closure. Preferably the opening has a diameter of about lmm.
The invention is generally embodied as a screw cap which is intended to close a bottle or other container by cooperation with a threaded spout of said container. As such the screw cap preferably comprises a plastics material such as polypropylene.
Preferably the detergent composition comprises at least one component which produces a gas, preferably the at least one component produces the gas by degradation, e.g. an oxygen based bleach such as hydrogen peroxide or other bleach, such as a chlorine based bleach.
In practice, the material of the sheet can be relatively thin material, for example 50 microns thick. The sheet material preferably comprises a plastics material such as PE or PVC.
The sheet may comprise a multi-layer material. In this case a lower (e.g. the lowermost) layer of the sheet is preferably formed such that it has an aperture. Moreover, the sheet aperture is preferably arranged on the closure such that locus of the sheet aperture forms a fluid channel with the closure opening. An upper layer of the sheet may be adhered to the first layer of the sheet in a manor such as that described above (the first and second region style of attachment) . In this way when there is a need to release pressure a vent passage may be created between the lower and upper layers of the sheet. The vent passage closes when there is no need for a pressure release.
In accordance with the second aspect of the invention there is provided a detergent package comprising a closure in accordance with the first aspect of the invention.
The above and further features and advantages of the invention will become clear from the following description of an embodiment thereof, reference being made to the accompanying drawings, in which Figure 1 is a top plan view of a detergent package provided with a closure in accordance with the present invention.
Referring to Figure 1, the closure 1 is attached by screwing to a detergent bottle (not shown) . The closure 1 comprises a pressure release aperture 2. Adjacent to the aperture 2 is a sheet of film material 3 secured to the closure 1 by adhesive. The sheet 3 comprises a numbers of regions: first regions 4 which are bonded to the closure 1 by an adhesive and a second region 5 which is arranged over the release aperture 2 and which is not bonded to the closure by an adhesive.
When a package formed as described above suffers from elevated internal gas pressure, initially, there will be little leakage of steam from the package. However, as the pressure of the package increases the second region 5 is eventually raised form the upper surface of the closure to define a channel through which gas may thereafter vent in a controlled manner.
As the pressure in the package is reduced the second region 5 is lowered until the seal above the release aperture 2 is restored and the closure is once more gas tight.