WO1999023318A1

WO1999023318A1 - Flexible film as a package for a toilet bowl dispenser

Info

Publication number: WO1999023318A1
Application number: PCT/IB1998/001636
Authority: WO
Inventors: Robert Corneel De Caluwe; Kirk Wallace Lake; John Russell Lawson; Greet Renee Els Francine Notele; Bruno Van Den Branden; Jean-Luc André Patrick VARLET
Original assignee: The Procter & Gamble Company
Priority date: 1997-10-31
Filing date: 1998-10-19
Publication date: 1999-05-14
Also published as: JP2001522007A; EP0913533A1

Abstract

The invention relates to a toilet bowl dispenser comprising a block (1), a package (2) for the block (1) and means for re-movably retaining the dispenser in the region of the rim of a toilet bowl, whereby the package (2) of the block (1) is made from a flexible film which is uniformly pierced or uniformly porous.

Description

FLEXIBLE FILM AS A PACKAGE FOR A TOILET BOWL DISPENSER

Technical field

The present invention relates to a flexible film used for a package for a toilet bowl dispenser.

Background of the invention

Toilet bowl dispensers are used for cleaning and deodorising toilets. Such dispensers are using the current of flush water for dispensing a chemically active composition which has a cleaning and deodorising action. Generally, such dispensers are composed of a block, a package for the block and a means for re-movably retaining the dispenser in the region of the rim of a toilet bowl. The block is formed from a chemically active composition which is drawn together with the flush water coming from the rim of the toilet. This block is maintained in a package which is typically a plastic made rigid cage letting flush water through. This cage is maintained under the rim in the way of the flush current by the retaining means, which is usually forming an extension of the rigid plastic cage forming a rigid plastic hook. An alternative package solution has also been introduced, in which the rigid plastic cage is replaced by a porous or pierced flexible film.

The present invention concerns a toilet bowl dispenser comprising a block, a package for the block and a means for re-movably retaining the dispenser in the region of the rim of a toilet bowl, the package being formed from a porous or pierced flexible film. Such a dispenser is known from the German Gebrauchsmuster G-8906 140.3.

Among the advantages of using a porous or pierced flexible film as a package for a toilet bowl dispenser is that the weight of such a package is much inferior than the weight of a rigid plastic cage fulfilling the same purpose. Consequently, the use of such a film is more environmentally friendly in so far as it is participating to a reduction of the amount of plastic released in the environment. Furthermore, the production cost of a package composed of a flexible film is lower than the production cost of a rigid plastic cage.

While having these and other advantages, flexible films, particularly pierced films, have disadvantages. For example, the dispenser has to be placed in a particular location to ensure sufficient ingress of water in the pierced holes while flushing. In addition, the block does not dissolve homogeneously as it dissolves mainly around the pierced holes of the package.

The invention seeks to provide a toilet bowl dispenser of the above mentioned kind which dissolves homogeneously and with a minimised dependence on its location.

Summary of the invention

In accordance with the invention, this object is accomplished in a toilet bowl dispenser of the above kind in that the film is uniformly porous or pierced.

Detailed description of the invention

Figure 1 presents five sections of five possible embodiments of a block and a package according to the invention.

Figure 2 is a section of a packaged block according to the invention after flushing. The invention relates to a toilet bowl dispenser which comprises a block 1 , a package 2 for the block 1 and a means for re-movably retaining the dispenser in the region of the rim of the toilet bowl. The retaining means is retaining the packaged block 1 in a location in the region of the rim of the toilet bowl, preferably under the rim, and is re-movable so that the dispenser can be removed once the block 1 is completely dissolved. It should be noted that it is preferable that the film composing the package 2 of the block 1 does not readily dissolve in water. Indeed, such a film could not be used as a package during use as it would be washed away, so that its packaging function would not be fulfilled: the block 1 itself would be directly dropped in the water. However, the film may be such that it is flushable. Such a dispenser is very widely used and has a passive functioning. Indeed, the dispenser is dispensing by means of the flush water. When the toilet bowl is flushed after use, the flush water is released from apertures provided under the rim of the toilet bowl and flows down into the receiving part of the toilet bowl. While the flush water flows down the bowl, it should intersect the dispenser, so that the dispenser will be wet. As the dispenser will be wet, the block 1 which is part of the dispenser will also be wet, and consequently release the active elements from which it is formed. Indeed, the block 1 is normally formed from a chemically active composition which will start acting once in contact with water. An example of chemical action due to wetting of the block 1 can be the release of perfume. Another example of chemical action may be the release of cleaning components which will be transported down in the bowl in the flow of the flush water.

Due to the fact that such a dispenser is a passive dispensing means depending on an external element, i.e. the flushing water flow, the relation between the dispenser and the flushing water flow has to be considered. Indeed, the flow of flushing water is usually not a homogeneous flow. The flow of flushing water is usually concentrated beside the apertures provided under the rim and releasing the water. For this reason, the functioning of a normal toilet bowl dispenser is dependant on its location. If such a dispenser is placed directly in the flow, the active elements from the block will be released in greater quantities, so that the block will be flushed away after only a few flushing operations. On the contrary, the block might be placed in a location where only a weak flow of water is obtained, so that the amount of active elements released will not be sufficient for cleaning and perfuming the toilet. This is an absolute location problem, as the entire block may be placed in a part of the bowl which is not convenient. Another problem of location is a relative location problem, whereby the block is not wet uniformly. The irregularity of the flow is such that a part of the block may be repeatedly widely wet whereas the rest of the block will not be wet in the same manner, so that the block will not be washed away evenly. This results in an unsatisfactory action of the dispenser. Indeed, at the beginning of use, the part which is widely wet will release large quantities of chemically active elements, thus providing an instantaneous perfume and cleaning action, even if part of the active elements will be flushed down the drain. However, once this part of the block will have been dissolved completely, the block will have to be displaced in order to locate the remaining of the block in a sufficient flow. Such a displacement is often causing a problem because it requires for the user to come into contact with the soiled retaining means. Some solutions have been proposed for solving the relative location problem, consisting in providing the package of the block with a limited number of openings placed in a particular manner, so that there is, for example, an opening for letting the flow in, and an opening for letting the flow out. By doing this, the advantage is that the manner in which the block will be wet can be predicted, and consequently controlled. A means for control is to provide the package with three openings allowing the flow in, and with only two letting the flow out, each opening having the same opened surface, as is presented in an embodiment of CH-A-675140. Consequently, there will be a delay during which some water will be left within the package, as more water can flow in than out at a given time, so that the block can be wet more evenly. However, this improvement in solving the relative location problem is rendering the absolute location problem more acute. Indeed, if the opening of the package for letting the flow in is not itself placed in the flow, the entire block will stay substantially dry. This means that not only the block has to be placed carefully in the flow, but the opening letting flow in has to be placed accordingly. Indeed, the flow may intersect part of the block without intersecting the opening letting flow in, so that use of the dispenser will not be satisfactory. The dispenser according to the invention is aiming at solving both the relative and absolute location problems.

This is achieved by using the uniformly porous or pierced film of the invention. Indeed the use of a film will provide the control on wetting solving the relative location problem by creating an inter-space between the package and the block in which the water can be retained, and by allowing a better control of the amount of water which is allowed to enter the film. Furthermore, the flow will be dispersed in a plurality of flows by the plurality of pores or pierced holes (20), so that the wetting will be more uniform. Not only the relative location problem is solved, but the absolute location problem is reduced. Indeed, as the porosity or piercing is uniform, it is sufficient that only a part of the block, and furthermore any part of the block, is intersecting the flow, as the pores or pierced holes are uniformly placed, and not in a precise location somewhere around the block.

If a part of the flexible film according to the present invention is intersecting a part of the flushing water, the water will enter the package through the pores or pierced holes (20) which are located in the part of the film which is intersecting the flow. By entering through these holes, a forceful flow will be divided into a plurality of streams. This reduction of the force of the flow will prevent accelerated dissolution of the block, so that the active elements composing the block are not taken straight away by the flush flow to be drained without having fulfilled their function. Once the streams enter the package, they may be submitted to a force of capillary attraction. Indeed, it is preferred that the package composed of the film is tightly wrapped around the block so that the space between the block and the package is sufficiently thin for allowing capillary attraction from one part of the film to an other, as could be obtained by flow wrapping. Indeed, such a uniform film is appropriate for high speed flow wrapping as it does not require to be specifically oriented because of its uniformity. Such a high speed process would have been difficult to apply to the traditional dispensers which are not uniform. Furthermore, the possibility to apply such a process to the dispenser of the invention is particularly appropriate if the retaining means of the dispenser is also made out of a flexible film, preferably forming one piece together with the package, so that the package and the retaining means may be flow wrapped together around the block, thus simplifying greatly the production of toilet bowl dispensers.

Indeed, the water which entered with the streams will wet the space between the package and the block uniformly, thus wetting the block uniformly, although any part or only one part of the dispenser may have been intersecting the flushing flow. By uniformly porous or pierced, it is meant that any substantial part of the film is porous or pierced in the same manner than any other substantial part of the film. Furthermore, the film according to the invention is flexible in order to take the shape of the block of which it is the package. Furthermore, because the film is flexible, the block will be maintained in tight contact with the film at least by gravity, thus further favouring capillary attraction of the water 3.

The dispenser according to the invention will not only solve location problems but timing problems. Indeed, when using traditional dispensers such as rigid plastic cages, the flow will enter and come out of the block straight away and with a relatively high force, thus carrying most of the active elements directly down the drain. This is a timing problem. Indeed, it is preferable to release the active elements after draining of the flush water, as is accomplished when using a dispenser according to the present invention. Firstly, as already mentioned above, a forceful flow will be divided in a plurality of streams, so that less active elements will dissolve straight away, as the force of the flow is lessened when passing the package. Any excess of water will not enter the package as the ingress of water is limited by the percent open area of the film which is fixed by the number and shape of the holes or pores (20). Preferably, the percent open area is comprised between 10 and 50 % of the entire surface of the film. Furthermore, tests showed that the dispenser of the invention has a weight evolution which can be readily controlled by acting on the size of the pores or pierced holes (20) and on the open percent area. Secondly, capillary attraction will allow complete and uniform wetting of the block, slowly dissolving active elements. Thirdly, the capillary force will retain at least part of the water 3 within the package, so that the active elements will have an effect which will last in time. This is particularly effective for perfume, thus allowing comfortable use for the following user of the toilets. In order to further improve the long lasting effect, it is preferred to use pores or holes (20) having a three dimensional conical shape which will favour the capillary force. The shape of the pores or holes may be various, comprising circles, rectangles or triangles for example. Furthermore, the pores or holes should preferably have a size comprised between 200 and 2000 μm, more preferably between 500 and 1000 μm, so that the capillary attraction will be further favoured. Preferred shapes for pores or pierced holes include conical shape (21 ), reversed conical shape (22), cylindrical shape (23), long cylindrical shape (24) or flat shape (25). Tests comparing the dispenser according to the invention with existing dispensers showed that the weight loss of the dispenser according to the invention would vary of less than 30 percent depending on the location, whereas a traditional dispenser will exhibit a difference of more than 80 percent in weight loss depending on its location.

It should be noted that the preferred percent open area of the film is comprised between 10 and 50 %, and more preferably between 20 and 40 % of the entire surface of the film, as such a percent open area is favouring bubbling of the dispensed mixture of water and active elements, thus allowing a better cling or adherence to the surface of the bowl which further improves the long lasting effect and also allows to improve the hygienic effect of the active elements of the block by increasing the time during which the active elements are in contact with the surface of the bowl. Furthermore, bubbling will be more likely to occur after the first uses of the block as the block will have absorbed water and will normally have adapted to the shape of the pores or holes, so that water will have to go through the active elements at each flushing operation.

In order to further improve the wetting of the block, the block may also be adapted for having a shape co-operating with the general curved shape of a toilet bowl. Indeed, the block may be bent in a curve following the curve of the toilet bowl. Bending of the block can occur after flow wrapping if the block is flow wrapped.

Claims

1. A toilet bowl dispenser comprising a block (1 ), a package (2) for the block (1 ) and a means for re-movably retaining the dispenser in the region of the rim of a toilet bowl, the package being formed from a porous or pierced flexible film, characterised in that the film is uniformly porous or pierced.

2. A dispenser as in claim 1 , whereby the retaining means is made from a flexible film.

3. A dispenser as in claim 2, whereby the retaining means and the package (2) are in one piece.

4. A dispenser as in claim 3, whereby the retaining means and the package (2) are flow wrapped around the block.

5. A dispenser as in claim 1 , whereby the film has a percent open surface area comprised between 10 and 50 % of the entire film surface.

6. A dispenser as in claim 1 , whereby the film is applied using a flow wrapping process.

7. A dispenser as in claim 1 , whereby the film does not dissolve in water.

8. A dispenser as in claim 1 , whereby the pores or holes (21 , 22) of the porous or pierced film have a three dimensional conical shape.

9. A dispenser as in claim 1 , whereby the pores or holes (20) of the porous or pierced film have a size between 200 and 2000 ╬╝m.

10. A dispenser as in claim 1 , whereby the block (1) is bent in a curve following the curve of the toilet bowl.