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Title:
A DEFORMABLE CONTAINER
Document Type and Number:
WIPO Patent Application WO/2017/182652
Kind Code:
A2
Abstract:
A deformable container (10) that is suitable for dispensing dishwasher machine cleaner in an automatic dishwasher. The container defines an interior volume (15) for a fluid, and comprises an outlet (70) fluidly connected to the interior volume (15). A portion of the container is deformable on reaching a predetermined temperature to reduce the size of the interior volume (15) for forcing the fluid out from the container via the outlet (70). A seal (45) at the outlet (70) is openable by the fluid forced from the interior volume (15) when the size of the interior volume (15) is reduced to control the escape of fluid from the container (10).

Inventors:
KRAJEWSKI KRZYSZTOF (NL)
LINK RAINER (DE)
MONTI LUCA (IT)
Application Number:
PCT/EP2017/059552
Publication Date:
October 26, 2017
Filing Date:
April 21, 2017
Export Citation:
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Assignee:
RECKITT BENCKISER FINISH BV (NL)
International Classes:
D06F39/02; A47L15/44; B65D83/00
Attorney, Agent or Firm:
CARLIN, Robert et al. (GB)
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Claims:
CLAIMS

1 . A deformable container, the container defining an interior volume for a fluid, and comprising an outlet fluidly connected to the interior volume, and a first seal at the outlet; wherein a portion of the container, upon being heated to a predetermined temperature, is caused by the heat to deform to reduce the size of the interior volume for causing the fluid from the interior volume to open the seal and pass out from the container via the outlet. 2. A deformable container according to any preceding claim, wherein the

predetermined temperature is between 50°C - 75°C.

3. A deformable container according to claim 1 :

wherein the seal is operable to open, and the size of the interior volume is operable to partially reduce, at a first predetermined temperature; and

wherein the size of the interior volume is operable to further reduce at a second predetermined temperature which is higher than the first predetermined temperature.

4. A deformable container according to claim 3, wherein the first predetermined temperature is between 50°C - 55°C, and wherein the second predetermined temperature is between 65°C - 75°C.

5. A deformable container according to any preceding claim, the container further comprising a frangible seal at the outlet.

6. A deformable container according to any preceding claim, wherein the first seal is linear.

7. A deformable container according to any preceding claim, wherein the container further comprises a plurality of corrugated channels which do not substantially reduce in size when the container reaches the predetermined temperature.

8. A deformable container according to claim 7, wherein the plurality of corrugated channels are located downstream of the first seal.

9. A deformable container according to any preceding claim, wherein the container comprises a rib which is not substantially deformable when the container reaches the predetermined temperature. 10. A deformable container according to claim 9, wherein the rib extends around a circumference of the interior volume.

1 1 . A deformable container according to claim 10, wherein the interior volume comprises no sharp edges in a region that is distal to the outlet and that is adjacent the rib.

12. A deformable container according to any preceding claim, wherein the container comprises a region proximal to the outlet which defines a concave indentation for assisting with the removal of fluid from the container when the container reaches the predetermined temperature, wherein the concave indentation defines a flow path for the fluid to the outlet which decreases in cross-section towards the outlet.

13. A deformable container according to any preceding claim, wherein the interior volume comprises a plurality of smaller volumes which are fluidly isolated from each other prior to the container reaching the predetermined temperature.

14. A deformable container according to any preceding claim, wherein the interior volume is less than or equal to 300ml prior to the container reaching the predetermined temperature. 15. A deformable container according to any preceding claim, wherein the size of the interior volume is operable to reduce by between 70% - 90% when the container reaches the predetermined temperature.

16. A deformable container according to any preceding claim, wherein the portion of the container is made of a shape-memory material.

17. A deformable container according to claim 16, wherein the shape-memory material is a shape-memory polymer.

18. A deformable container according to claim 17, wherein the shape-memory polymer comprises polyethylene terephthalate.

19. A deformable container according to any preceding claim, wherein the first seal is made of a material comprising polyethylene, polyethylene terephthalate, and

polypropylene.

20. A deformable container according to any preceding claim, wherein the first seal comprises a filleted/chamfered edge which is exposed to the interior volume for assisting with the opening of the first seal when the container is heated to the predetermined temperature.

21 . A deformable container according to any preceding claim, wherein the container is for application of a liquid detergent to the interior of an automatic dishwasher.

22. A deformable container according to claim 21 , wherein the liquid detergent is a dishwasher machine cleaner.

23. A deformable container according to claims 21 or 22, wherein the container comprises an attachment means for attaching the container to the interior of an automatic dishwasher.

24. A deformable container according to claim 23 when further dependent on any of claims 9-1 1 , wherein the attachment means is located on the rib.

25. A deformable container according to any preceding claim, wherein the interior volume contains a dishwasher machine cleaner formulation.

26. The use of a deformable container according to claim 25 in an automatic dishwasher.

27. A method for dispensing a fluid from a deformable container defining an interior volume containing the fluid, and comprising an outlet fluidly connected to the interior volume, and a first seal at the outlet, the method comprising the steps of:

placing the container in a heated environment; heating the container in the heated environment to a predetermined temperature; wherein upon the container being heated to the predetermined temperature; a portion of the container is caused by the heat to deform to reduce the size of the interior volume for causing the fluid from the interior volume to open the first seal and pass out from the container via the outlet.

28. A method according to claim 27:

wherein the seal opens, and the size of the interior volume partially reduces, at a first predetermined temperature; and

wherein the size of the interior volume further reduces at a second predetermined temperature which is higher than the first predetermined temperature.

29. A method according to claim 28, wherein the first predetermined temperature is between 50°C - 55°C, and wherein the second predetermined temperature is between 65°C - 75°C.

30. A method for manufacturing a deformable container defining an interior volume for a fluid, and comprising an outlet fluidly connected to the interior volume, and a first seal at the outlet, the method comprising the step of:

passing two adjacent sheets of material together through a plurality of sequential heated dies such that the heated dies shape the sheets of material into the shape of the deformable container.

31 . A method according to claim 30, wherein the plurality of sequential heated dies comprises a first set of heated dies and a second set of heated dies;

wherein the method comprises the steps of:

passing the two adjacent sheets of material together through the first set of dies to shape the adjacent sheets of material into a partly formed container comprising the interior volume;

injecting fluid into the interior volume of the partly formed container; and

passing the partly formed container containing the fluid through the second set of dies to shape the partly formed container into the deformable container.

32. A deformable container as substantially hereinbefore described and with reference to the accompanying drawings.

Description:
A DEFORMABLE CONTAINER

The present invention relates to a deformable container, in particular a deformable container suitable for dispensing dishwasher machine cleaner in an automatic dishwasher.

BACKGROUND

It is known that automatic dishwashers require intermittent cleaning to remove residues, such as limescale, which may have built up in the machine over time. Typically, such residues are removed by operating the automatic dishwasher with a container inside of it which contains dishwasher machine cleaner. During the operation of the dishwasher, the heat generated inside of the dishwasher causes the dishwasher machine cleaner from the container to be dispensed into the dishwasher to remove the residues. After operation of the dishwasher, the container is removed from the cleaned dishwasher, and the container then disposed of.

Dishwasher machine cleaner formulations typically include, but are not limited to: water; acidifiers such as citric acid; builders such as HEDP; non-ionic surfactants; and hydrotropes such as sodium cumenesulphonate. Further information on dishwasher machine cleaner formulations is contained within WO 2007/060439, the contents of which are herein incorporated by reference.

WO 2009/095638 describes an existing container for use in dispensing dishwasher machine cleaner in an automatic dishwasher. The container therein disclosed has a wax closure at one end. When the container is placed in the dishwasher with the wax closure facing down and the dishwasher then operated, heat generated inside the dishwasher causes the wax plug to melt allowing dishwasher cleaner inside the container to be dispensed.

The number of components which make up the container from WO 2009/095638 (including the main bottle; the wax seal; and the screw-cap) make this container difficult and time-consuming to produce. There is the need, therefore, for an improved container for dispensing dishwasher machine cleaner in an automatic dishwasher which is simpler to manufacture, and easier to produce. SUMMARY OF THE INVENTION

According to a first aspect of the present invention, there is provided a deformable container, the container defining an interior volume for a fluid, and comprising an outlet fluidly connected to the interior volume, and a first seal at the outlet;

wherein a portion of the container, upon being heated to a predetermined

temperature, is caused by the heat to deform to reduce the size of the interior volume for causing the fluid from the interior volume to open the first seal and pass out from the container via the outlet. The present invention thus provides a deformable container with few components, and which is easy and cheap to manufacture. Since the size of the container is reduced during use, this also makes the container easier to dispose of once used.

In its most general form, the deformable container is adaptable for use in any heated environment where fluid requires dispensing at a predetermined temperature.

Where the deformable container is intended for use in an automatic dishwasher or a washing machine, preferably the predetermined temperature is between 50°C - 75°C, more preferably 65°C - 75°C.

Preferably, the first seal is operable to open, and the size of the interior volume is operable to partially reduce, at a first predetermined temperature; and the size of the interior volume is operable to further reduce at a second predetermined temperature which is higher than the first predetermined temperature. In such cases, the first predetermined temperature may be between 50°C - 55°C, and the second predetermined temperature between 65°C - 75°C.

To prevent the container from prematurely leaking any fluid through the outlet, preferably the container further comprises a frangible seal at the outlet. Preferably the frangible seal is operable to be snapped off or torn off by the user just prior to the container being placed in a heated environment.

Preferably, the first seal is linear, rather than curved, to improve the flow of fluid through the seal. To further control the escape of fluid from outlet, preferably the container further comprises a plurality of corrugated channels which do not substantially reduce in size when the container reaches the predetermined temperature. Preferably the plurality of corrugated channels are located downstream of the first seal.

The container may comprise a rib which is not substantially deformable when the container reaches the predetermined temperature. Preferably, the rib extends around a circumference of the interior volume. The rib helps to retain the structure of the deformable container at the predetermined temperature, and works with the deformable portions from the container to help guide fluid out of the container when it is deformed.

When the container comprises a rib, the container may comprise an interior volume comprising substantially no sharp edges in a region that is distal to the outlet and that is adjacent the rib. The amount of permissible sharpness in these edges will depend on the size of the container. Preferably however, such edges should have a radius of curvature of at least 3mm.

Preferably, the container comprises a region proximal to the outlet which defines a concave indentation for assisting with the removal of fluid from the container when the container reaches the predetermined temperature, wherein the concave indentation defines a flow path for the fluid to the outlet which decreases in cross-section towards the outlet.

In some cases, the interior volume from the container may comprise a plurality of smaller volumes which are fluidly isolated from each other prior to the container reaching the predetermined temperature. This arrangement allows, for example, two incompatible liquids which require separation from each other prior to use, to be kept separated until the point when the container is deformed.

Particularly in situations where the deformable container is intended for use in an automatic dishwasher or a washing machine, preferably the interior volume is less than or equal to 300ml prior to the container reaching the predetermined temperature.

The size of the interior volume is preferably operable to reduce by between 70% - 90% when the container reaches the predetermined temperature. The reduction in the size of the interior volume may be achieved by a portion of the container which expands into the interior volume when the container is at the

predetermined temperature. Preferably however, the reduction in the size of the interior volume is achieved by the portion of the container being made of a material comprising, or consisting of, a shape-memory material, such as a shape-memory alloy or a shape- memory polymer. An example of a suitable shape-memory polymer is PET (polyethylene terephthalate).

The first seal may comprise a filleted/chamfered edge which is exposed to the interior volume for assisting with the opening of the first seal when the container is heated to the predetermined temperature. In this way, when the container is heated to the predetermined temperature, any fluid in the interior volume of the container is able to exert a peeling force on the filleted/chamfered edge to help peel the first seal open. As mentioned previously, preferably the container is for application of a liquid detergent to the interior of an automatic dishwasher. In such cases, the liquid detergent is preferably a dishwasher machine cleaner.

To assist with the mounting of the container when it is used in an automatic dishwasher, preferably the container comprises an attachment means for attaching the container to the interior of an automatic dishwasher. In such cases, and where the container additionally comprises a rib, the attachment means is preferably located on the rib. Preferably, the interior volume contains a dishwasher machine cleaner formulation.

According to a second aspect of the present invention, there is provided a use of a deformable container according to the first aspect in an automatic dishwasher. According to a third aspect of the present invention, there is provided a method for dispensing a fluid from a deformable container defining an interior volume containing the fluid, and comprising an outlet fluidly connected to the interior volume, and a first seal at the outlet, the method comprising the steps of:

placing the container in a heated environment;

heating the container in the heated environment to a predetermined temperature; wherein upon the container being heated to the predetermined temperature; a portion of the container is caused by the heat to deform to reduce the size of the interior volume for causing the fluid from the interior volume to open the first seal and pass out from the container via the outlet.

In this method, preferably the seal opens, and the size of the interior volume partially reduces, at a first predetermined temperature; and the size of the interior volume further reduces at a second predetermined temperature which is higher than the first predetermined temperature. In this case, the first predetermined temperature may be between 50°C - 55°C, and the second predetermined temperature may be between 65°C - 75°C.

According to a fourth aspect of the present invention, there is provided a method for manufacturing a deformable container defining an interior volume for a fluid, and comprising an outlet fluidly connected to the interior volume, and a first seal at the outlet, the method comprising the steps of:

passing two adjacent sheets of material together through a plurality of sequential heated dies such that the heated dies shape the sheets of material into the shape of the deformable container.

In this method, preferably the plurality of sequential heated dies comprises a first set of heated dies and a second set of heated dies; and preferably the method comprises the steps of:

passing the two adjacent sheets of material together through the first set of dies to shape the adjacent sheets of material into a partly formed container comprising the interior volume;

injecting fluid into the interior volume of the partly formed container; and

passing the partly formed container containing the fluid through the second set of dies to shape the partly formed container into the deformable container.

DESCRIPTION OF THE FIGURES

The invention will now be described, by example only, with reference to the accompanying drawings in which:

Figure 1 shows a perspective view of a container in accordance with the invention. Figure 2A shows a bottom view of the container of Figure 1 ;

Figure 2B shows a front side view of the container of Figure 1 ;

Figure 2C shows a top view of the container of Figure 1 ; and

Figure 2D shows a side end view of the container of Figure 1 .

Figure 3A shows a first stage of operation of the container shown in Figure 1 ;

Figure 3B shows a second stage of operation of the container shown in Figure 1 ; and Figure 3C shows a third stage of operation of the container shown in Figure 1 .

Figure 4A shows an image of a container similar to the container shown in Figure 1 ; Figure 4B shows an image of the container of Figure 4A after having been used in an automatic dishwasher;

Figure 4C shows an image of the container of Figure 4B after having been used in an automatic dishwasher and whilst still inside the tray of an automatic dishwasher.

Figure 5 shows a table illustrating the effectiveness of various differently shaped containers when heated. Figure 6 shows a cross-section view of a different container in accordance with the invention.

Figure 7 shows a front view of a container having a curved weak seal and a close up view of the curved weak seal.

Figure 8 shows an image of a weak seal of a container similar to the container shown in Figure 7.

Figure 9 shows a side end view of the container and the fluid-actuated seal of the container.

DETAILED DESCRIPTION With reference in particular to Figures 1 and Figures 2A-2D, there is shown a container 10 for dispensing a fluid. The container is predominately made of a shaped memory-polymer, such as PET, and defines an interior volume 15 for holding a fluid, such as dishwasher machine cleaner. The interior volume is divided into a first and second smaller region 20;25. Each of the two smaller regions is fluidly connected to a plurality of parallel corrugated channels 30 located at the top of the container. The channels 30 act as an outlet for the fluid to escape from the container as will be described, and do not reduce in size when heated. Prior to use, the top ends of the plurality of channels 30 are covered by a frangible seal 35 which is operable, in use, to be snapped off or torn off by the user along a fault line 40 extending substantially perpendicular to the direction of the corrugated channels 30.

Located between the bottom end of the plurality of channels 30 and the interior volume 15 is a fluid-actuated seal 45. The fluid actuated seal 45 extends across the entire width of the parallel corrugated channels 30 and preferably extends in a linear direction 46 which is substantially perpendicular to the direction of the corrugated channels 30.

In an example the fluid-actuated seal has a width, defined by the distance between the corrugated channels 30 and the interior volume 15, between 1 mm and 3mm, for example 1.5mm to 2.5mm, for example 1 .8mm to 2.2mm. The seal width may be 1 .5mm, 1.7mm, 1 .9mm, 2.1 mm, 2.3mm, 2.5mm and/or 2.6mm. The fluid-actuated seal may have a uniform width or the width of the fluid-actuated seal may vary, for example the fluid- actuated seal may have an area with a smaller seal width to provide a non-uniform seal strength.

In the example illustrated in Figures 7 and 8 the fluid-actuated seal 45 comprises a curved contour. As shown in Figure 8 the weak seal comprises a first curved contour 47 located between the plurality of channels 30 and the interior volume 15 of the first smaller region 20 and a second curved contour 48 located between the plurality of channels 30 and the interior volume 15 of the second smaller region 25. The first curved contour 47 directs the fluid towards a first apex 47a and the second curved contour 48 directs the fluid towards a second apex 48a so that the internal pressure is greater and the seal starts to open at this point. In the example illustrated in Figures 7 and 8 the apex of first and second curved contours 47;48 comprises a discontinuity in the curvature i.e. the apex 47a;48a defines a single point. In the example illustrated in Figures 7 and 8 the width of the seal is non-uniform. The width of the seal is less close to the apex of the curve. The reduction in the width of the seal weakens the seal at this point relative to the wider seal. The narrower weaker seal requires a lower pressure to open compared to the wider seal. In the example illustrated the seal width gradually declines away from the apex of the curve. The width of the seal may be 3mm away from the apex and 2mm at the apex of the curved contours 47;48.

The fluid-actuated seal may also have a chamfered edge. As illustrated in Figure 9 the fluid-actuated seal 45 may have a chamfered edge 51 located adjacent to the first and second smaller region 20;25. The chamfered edge gradually increases the seal pressure from the outer edge between the interior volume 15 to the centre of the seal 45 and therefore reduces the initial peeling force so that fluid pressure required to open the fluid- actuated seal is reduced.

Each of the first and second smaller region 20;25 comprises a front side wall 50 and a rear side wall 55 which are deformable when heated to a predetermined temperature. A strengthening rib 60, which does not substantially deform when heated to this

predetermined temperature, and which preferably has a greater thickness than the front side wall 50 and the rear side wall 55, extends around the side and top portions of the interior volume 15 to provide rigidity to the container 10 at the predetermined temperature.

A partitioning rib 65, having similar properties to the strengthening rib 60, extends from the fluid-actuated seal 45 to the bottom of the container 10 to isolate the first smaller region 20 from the second smaller region 25.

A fluid port 80 is provided at the top of each the first and second smaller region 20;25 to allow fluid to be inserted therein during the forming process of the container 10 as will be described.

The container 10 is also provided with attachment means, shown in Figure 1 as hook shaped portions 71 in the strengthening rib 60, for allowing the container 10 to be attached in an upright position to an object, although more preferably between the supports of a dishwasher tray when the container 10 is located in an inverted position inside a dishwasher, as will be described. Operation of the container 10 shown in Figure 1 and Figures 2A-2D is described with reference to Figures 3A-3C, and also Figures 4A-4C. Initially, a user grips the container and snaps off the frangible seal 35 along the fault line 40 (see Figure 3B). Although not shown in the Figures, rather than being snapped off, the frangible seal 35 may take the form of a tear-off strip which tears along the fault line 40. Once the frangible seal 35 is removed, this exposes the plurality of parallel corrugated channels 30. The exposed top surface from these channels 30 forms the outlet 70 through which fluid can escape from the container 10.

Once the outlet 70 is formed, the container 10 is then inverted and placed between the supports of a dishwasher tray, as shown in Figure 3C, and such that the hook shaped portions 71 engage against the bottom of the dishwasher tray (see Figure 4C). In this inverted position, fluid contained in the first and second smaller region 20;25 is prevented from passing to the outlet 70 via the corrugated channels 30 by the fluid-actuated seal 45, which at this stage remains closed.

The dishwasher is then operated with the container 10 located inside.

As the interior of the dishwasher heats up, the heat generated within the dishwasher causes the deformable container to heat up. In the case of a container made of PET, once the container reaches a temperature of approximately 50°C - 55°C, the front side wall 50 and the rear side wall 55 of the container deform slightly inwardly. The initial deformation of these side walls 50;55 causes the size of the first and second smaller region 20;25 to reduce, which increases the pressure of the fluid contained within these regions 20;25.

The increased pressure of the fluid exerts a pressure on the fluid-actuated seal 45 which forces it to peel open, allowing an initial portion of the fluid from the container 10 to pass through the channels 30 and out the outlet 70 into the dishwasher.

As the interior temperature inside the dishwasher continues to increase towards the intended operating temperature of the dishwasher, typically around 65°C - 75°C, the increase in temperature causes further inward deformation of the front side wall 50 and the rear side wall 55 of the container 10 such that the container is deformed into a flattened state as shown in the images of Figure 4B and Figure 4C. In this state, any fluid in the interior volume is forced by the flattened side walls 50;55 through the fluid-actuated seal 45 and out of the outlet 70. In this flattened state shown in Figure 4B and 4C, the interior volume of the container is around 10%-30% of its original size as shown in Figure 4A.

It will be seen from Figure 4C that the hook shaped portions 71 in the strengthening rib 60, which engage against the bottom of the dishwasher tray, help keep the container in its inverted position, even when it is deformed. This is important since fluid escape from the container is optimized when the container is in an inverted position as shown in Figure 4C, rather than in a flat position. The hook shaped portions 71 , when engaged against the bottom of the dishwasher tray also keep the container straight in use and prevent it from folding like a book onto itself when it deforms. Such folding is disadvantageous since it reduces the amount of fluid which can escape from the first and second smaller regions 20;25. The hook shaped portions 71 also prevent the container 10, once emptied and deformed, from being displaced inside the dishwasher by the pressurized water jets emitted from the rotating spray arm of the dishwasher.

The extent to which fluid is forced out from the first and second smaller region 20;25 depends on the shape of the first and second smaller region 20;25, and the extent to which the front side wall 50 and the rear side wall 55, which are made of a shaped-memory polymer, inwardly deform when they are heated to the predetermined temperature.

To improve the extent to which fluid inside the first and second smaller region 20;25 is drawn towards the channels 30, the regions of the front side wall 50 and the rear side wall 55 which are away from the outlet 70 and which are proximal to the strengthening rib 60 and the partitioning ribs 65 should comprise no sharp edges, since these sharp edges when deformed can create narrow capillaries which retain fluid inside the first and second smaller region 20;25, even after these regions 20;25 have deformed. To minimize such fluid retention inside the first and second smaller region 20;25, preferably the regions of the front side wall 50 and the rear side wall 55 which are proximal to the strengthening rib 60 and the partitioning ribs 65 comprise a fillet 90.

To further improve the extent to which fluid inside the first and second smaller region 20;25 is drawn towards the channels 30, each of the front side wall 50 and the rear side wall 55 may comprise a concave indentation 75 in a region proximal to the channels 30 and the outlet 70 which decreases in cross-section towards the outlet, and which does not deform when heated. Figures 4A-4C show this most clearly, where it can be seen that the concave indentations 75 have the same shape both before and after the container 10 has been heated and deformed in an automatic dishwasher.

Having the fluid-actuated seal 45 formed in a straight line, rather than as a curve, also results in improved transfer of fluid from the first and second smaller region 20;25 through to the channels 30. To illustrate how the shape of the first and second smaller regions 20;25 affects how these regions deform and expel fluid when heated, Figure 5 shows various differently shaped deformable containers before and after use inside an automatic dishwasher operated at 65°C. As can be seen in Figure 5, the pillow shaped container having the concave indentations 75 and the fillet 90 is the most effective of the shown containers at expelling fluid.

Although the deformable container shown in the Figures has been described as being suitable for dispensing dishwasher machine cleaner in an automatic dishwasher, it will be appreciated that the container may be modified for use in any situation where a fluid requires dispensing in an environment only when the temperature of the environment reaches a predetermined level. One such situation includes dispensing detergent inside a washing machine.

The choice of shape-memory polymer for the deformable portions of the container 10 will depend on the intended application for the container 10. When used inside a dishwasher, the deformable portions of the container 10 are preferably predominately made of a shape-memory polymer which has a glass transition temperature (TG) in the region of the operating temperature inside a dishwasher. Accordingly, for use inside a dishwasher, the selected shape-memory polymer should have a glass transition temperature of between 50°C - 75°C. PET is one such suitable shape-memory polymer.

Once the choice of shape-memory polymer has been made for the container 10, manufacture of the container 10 is achieved by heating the container above its glass transition temperature and then shaping the container in these conditions, for instance in a thermoforming process or a stretch blow moulding process, into a stressed shape. Importantly, the portions of the container that are stressed in the forming process are the portions of the container that are intended to be deformed in use of the container. These portions include the front side wall 50 and a rear side wall 55; but not the partitioning rib 65, the strengthening rib 60, or the concave indentations 75. Once the stressed shape is achieved the container 10 is constrained in this stressed shape and simultaneously cooled back below its glass transition temperature. Once cooled, the container 10 is set in the stressed shape, which is the shape shown in Figure 1 and Figures 2A-2D.

When the container 10 is subsequently heated above its glass transition temperature in use, e.g. inside a dishwasher, the container 10 is allowed to revert to a shape which is less stressed. This less stressed shape corresponds to the shape of the container when it is inwardly deformed.

From the above, it will be appreciated that how the container 10 is manufactured, and placed in a stressed shape, affects the extent to which the container inwardly deforms when it is heated to the predetermined temperature. It will therefore be appreciated by the skilled person that the exact material selected (together with its associated glass transition temperature) for the container, and the particular manufacturing conditions used to shape the container in its stressed shape, will thus vary depending on the intended application for the container.

The forming process used to create the container 10 can be performed in a number of different ways, as required, to allow for fluid to be inserted into of each the first and second smaller region 20;25. In one forming process, the container 10 is formed by passing two adjacent sheets of material through a series of sequential heated dies, wherein each heated die operates to partly shape the sheets of material into the shape of the container 10. In one operation, the adjacent sheets of material are passed through a first set of heated dies such that the sheets form the container 10 but without its fluid ports 80 sealed. From this partly-formed state, the partly-formed container is placed in an upright position and fluid is then inserted into each of the first and second smaller regions 20;25 via the unsealed fluid ports 80. Once the container is filled, the partly-formed container is passed through a further set of heated dies to seal the fluid ports 80 such to seal the fluid inside the first and second smaller regions 20;25, and such to create the container 10. ln relation to the faces of the portions of the heated dies which form the adjacent sheets of material into the strengthening rib 60, and any partitioning rib 65, preferably these faces are textured, such as corrugated. In this way, when these faces from the heated dies contact the portions of material which form the strengthening rib 60 (and any partitioning rib 65), the die faces deform these portions of material such they share a greater area of contact compared with if they were formed using non-textured die faces. This additional contact area improves the sealing properties of the strengthening rib 60 and the partitioning rib 65. It will be appreciated that various modifications can be made to the container herein described. For instance, it will be appreciated that rather than the interior volume of the container being made of two isolated regions 20;25, the interior volume may be separated into any number of such regions (including only one) depending on the number of partitioning ribs 65 (if any) used.

The size of the container 10 and its interior volume 15 may also vary depending on the intended application for the container 10. When being used to hold dishwasher machine cleaner, the interior volume may ideally hold no more than 300ml, preferably no more than 250ml, and further preferably no more than 200ml, of dishwasher machine cleaner.

The dimensions of the container may also vary depending on the intended application for the container 10. When being intended for use in an automatic dishwasher, the maximum height of the container may be approximately 135mm, the maximum width of the container approximately 150mm, and the maximum depth of the container approximately 35mm.

The reduction in size of the interior volume need not necessarily be achieved using a shape-memory material. A similar reduction in size may be achieved using a bag-in-box type container as shown in Figure 6. In this arrangement, the container 100 may be provided with a rigid outer housing 102 in which is located a resilient container 104 defining an interior volume for a fluid to be dispensed. A fluid-actuated seal 145, which may be similar to the fluid-actuated seal 45 described in Figures 1 and Figures 2A-2D, provides an outlet for the fluid from the resilient container 104. A heat-transfer fluid 103 (such as air), which expands when heated, is located between the rigid outer housing 102 and the resilient container 104.

In operation of the container 100 shown in Figure 6, when the container 100 is heated to the predetermined temperature, the heat-transfer fluid between the rigid outer housing 102 and the resilient container 104 expands causing the resilient container 104 to inwardly deform, which increases the pressure of the fluid inside the resilient container 104. As the pressure exerted on this fluid increases, the pressure this fluid exerts on the fluid-actuated seal 145 also increases. Ultimately, the pressure on the fluid-actuated seal 45 forces it to open, allowing fluid out of the container 100.