Background of the invention The applicant's patent specification No. PCT/NZ96/00008 discloses a container of variable volume. The container includes a bladder located within a number of interlocking sleeves. The volume of the bladder can be varied by moving at least one of the outer sleeves relative to another of the outer sleeves.

If is often important to minimise the air in contact with fluid within a container.

This is particularly useful when storing aerated drinks, such as sparkling wine and soft drinks. However it is also useful when storing sauces as these degrade when they contact air.

Another area where it is particularly important to minimise the air in contact with fluid is in the photographic industry. As photochemicals oxidise rapidly, they are sold in ready to use bottles of a required volume. This is expensive and is not ecologically sound.

It is also useful to be able to deliver a measured dose of fluid from a container.

Sometimes it is important that a precise dose is provided each time. Although certain mechanisms go some way to achieving this, none are very successful.

Pump mechanisms, as an integral part of a cap of a container, are sometimes used to deliver fluids. However pumps have a number of disadvantages. Firstly, pumping fluids such as a sauce changes the rheological properties of the sauce and hence alters its texture. Secondly, if the fluid is highly viscose, it does not flow properly through the pump and hence an accurately measured dose is difficult to obtain. The problem is accentuated as the fluid level falls such that when a small amount of fluid remains at the bottom of the container, the dispensing of a dose can be very inaccurate. Hence it is difficult to obtain an accurately measured dose using the pump when only a small amount of fluid remains in the container. Thirdly, the use of pump mechanisms causes oxygen degradation of the contents of the container. For example, tomato sauce turns dark red due to oxygen degradation over a period of time.

A combination pump mechanism and internal bladder is sometimes used to dispense a product such as toothpaste. A disadvantage with this type of mechanism is that as the bladder collapses from the bottom up, the packaging becomes top heavy and the container is liable to tip over. Also, unless the container is transparent, it is not known how much product remains within the container.

Another problem with "toothpaste style" pump mechanisms is that when the fluid in the container becomes low, it becomes almost impossible to remove all the fluid as the bottom of the pump must, of necessity intrude into the bladder space.

Other containers use a bladder type system incorporating a tap. Examples of such mechanisms are found on wine boxes and fruit juice boxes. A major disadvantage of such mechanisms is that the liquid inside the box cannot be completely removed without removing the bladder from the box. This is cumbersome and inconvenient.

Disclosure of the Invention It is an object of the invention to provide a container which goes at least some way in overcoming at least some of the above disadvantages.

It is another object of this invention to provide a container in which the volume of fluid held in the container can be dispensed in measured doses whilst minimising the air in contact with the fluid.

Within this specification, the term "fluid" means any flowable substance and includes liquids, sauces, glues, lotions, pastes, toothpaste and similar substances.

According to one aspect of the present invention, there is provided a container wherein the volume of fluid held therein can be dispensed in measured doses whilst minimising air contact with the fluid.

The fluid is preferably held in an inner flexible member located within the container.

A piston-like mechanism may be provided and the inner flexible member may rest on a base of the piston. Alternatively, the base may be located above and rest on the inner flexible member. The base of the piston may be capable of moving up or down relative to the container in discrete steps such that each movement of the base causes a predetermined volume of fluid to be dispensed from the inner flexible member.

The invention provides a container comprising an external casing, wherein an inner flexible member and a piston are located within the casing such that as the piston is moved in a discrete step relative to the external casing, fluid within the member is dispensed in a measured dose whilst minimising air contact with the fluid.

The container may include a ratchet mechanism in which the base of the piston is adapted to move in discrete steps within slots in the external casing thus dispensing a specific amount of fluid from the inner flexible member, as the base moves up each step in the external casing.

The ratchet mechanism may comprise one or more ratchet slots running up the external casing of the container and a series of retaining slots at intervals along the ratchet slot. The piston mechanism is preferably adapted to move up the ratchet slot and be inserted into at least one retaining slot. This retention results in a specific amount of fluid being dispensed from the container.

The invention also provides a telescoping container comprising an external casing, and wherein an inner flexible member and a piston are located within the casing such that as the container shortens via a telescoping mechanism, a measured dose of fluid within the bladder is dispensed from the container whilst minimising air contact with the fluid.

The telescoping container may also include a ratchet mechanism. The ratchet mechanism may include a series of ratchet sections within the external casing.

When the container is pushed, it telescopes down by at least one ratchet section, dispensing a specific dose or fluid from the inner flexible member. The ratchet mechanism may include ratchet slots and retaining slots as described above.

The container may include a top section comprising a dispensing mechanism similar to an optic on a spirits bottle. The optic-like dispensing mechanism may be adapted to operate to dispense a measured amount of fluid each time the container is reduced in size. Hence a measured dose of fluid is dispensed each time the container is pushed making it shorter. The shortening of the container may be via a telescoping piston type arrangement or via a ratchet type arrangement.

The container may telescope, non-telescope or concertina. The container may telescope upwards or downwards.

Brief DescriDtion of the Drawings Further aspects of the invention will become apparent from the following description which is given by way of example with reference to the accompanying drawings in which: Figure 1 shows a perspective view of the invention according to one embodiment of the invention; Figure 2 shows a cross-section view of a container according to the embodiment shown in Figure 1; Figure 3 shows a perspective view of a container according to a second embodiment of the invention; Figure 4 shows a cross-sectional view of the container shown in Figure 3; Figure 5 shows a perspective view of a container according to a third embodiment of the invention; and Figure 6 shows a cross-section view of the container shown in Figure 5.

Best mode for carrying out the invention In the embodiment shown in Figures 1 and 2 the container 2 includes an external casing 4. An inner flexible member 6 is located within the casing 4. The inner flexible member 6 is attached either permanently or semi-permanently to an upper portion 8 of the container 2. The advantage in the inner flexible member 6 being attached semi-permanently to the upper portion of the container 8 is that the inner flexible member 6 can be replaced when empty. This will decrease the amount of waste, will be more cost-effective and environmentally friendly.

The container 2 includes a ratchet mechanism 10. The ratchet mechanism 10 allows the container to be emptied in discrete steps. In Figure 2, six discrete steps of the ratchet mechanism 10 are shown. However, it will be appreciated that any number of steps are possible and included within the scope of the invention. The ratchet mechanism 10 includes a base 1 2 with a lug 1 8 and a button 20. The base portion 12 is adapted to move up two ratchet slots 14 in the surface 4 of the container 2. These ratchet slots 14 are longitudinal slots running up the external casing 4 of the container 2.

The ratchet mechanism 10 also includes a series of retaining slots 1 6 in the surface of the container 4. These are shown as retaining slots 1 6. These retaining slots 1 6 are adapted to retain the base 1 2 of the ratchet mechanism 1 0.

The base 1 2 is adapted to move up the longitudinal slots 1 4 and rest in any one of the retaining slots 1 6. When the ratchet mechanism 10 is moved upwards from one retaining slot 1 6 to another 16, a predetermined volume of fluid within the inner flexible member 6 is dispensed from the container 2.

Pressure must be applied to button 20, located on lug 1 8 before the lug 1 8 is able to move between adjacent retaining slots 1 6.

Thus, as the base 1 2 moves up the ratchet mechanism 10 in a discrete series of steps, a measured dose of fluid is dispensed from the inner flexible member 6 of the container 2 as each retaining slot 16 is reached. A dispensing spout 3 is provided for dispensing the fluid. Thus a measured dose of fluid is provided whilst minimising the amount of air within the container 2 as the inner flexible member is compressed by the base 1 2.

A second embodiment of the invention is shown in Figures 3 and 4 which illustrate a telescoping container 30. The container 30 has a number of interlocking sleeves 32. The volume of the container can be altered by moving at least one sleeve relative to another. In the base 34 of the container 30 is a piston 36. As the container telescopes down and thereby becomes shorter, the piston 36 compresses an inner flexible member or bladder 38.

When the container 30 has telescoped down to its fullest extent, the piston 36 is at a position such that the inner flexible member or bladder 38 is totally compressed and therefore devoid of any fluid contents. In this way, all the fluid within the bladder 38 is removed.

Also, the piston 36 compresses the bladder 38 which ensures that no air is contained within the bladder 38. Hence there is minimum contact between the fluid in the bladder 38 with air.

The top section 40 of the container 30 comprises an optic-like dispensing mechanism 42. The optic mechanism 42 is adapted to provide a specific, measured dose of fluid from within the bladder 38. Each time the container 30 is telescoped down, the optic mechanism 42 is operated thus providing a measured dose of fluid. Hence a measured dose is provided each time the container 30 is pushed. Hence a telescoping piston-type arrangement is provided which provides a measured dose of fluid each time the container 30 is pushed.

The base 34 may be removable to allow for the removal and insertion of a clean bladder 38. Alternatively, or in addition, the top 40 may be adapted to be removed for changing the bladder 38.

Figures 5 and 6 illustrate a third embodiment according to the invention. The container 50 is a telescoping container but, in addition, contains a series of ratchet sections, 52, similar to the ratchet mechanism provided in embodiment 1.

A button 54 is provided on the ratchet mechanism 52. Each time the button 54 is pushed, the container becomes shorter by telescoping and the ratchet mechanism moves up by one ratchet section 52. The container also includes an inner flexible bladder 56 such that when the ratchet mechanism moves up a section, a specific, measured dose of fluid from within the bladder 56 is dispensed.

The container 50 could be adapted to telescope either downwards or upwards although upwards is preferred such that all the fluid may be removed.

A measured dose of fluid is thus provided whilst minimising the amount of air in contact with the fluid in the bladder 56. As the piston 58 moves up the container 50, the fluid is dispensed in measured doses. Once the piston 58 is at its uppermost level, all the fluid will have been removed from the container 50.

It will thus be seen that the present invention provides a container wherein the volume of the fluid held therein can be dispensed in measure doses, whilst minimising air in contact with the fluid.

Wherein the aforegoing description, reference has been made to integers of components having known equivalents, then such equivalents are incorporated as if individually set forth.

Although this invention has been described by way of example and with reference to possible embodiments thereof, it is to be appreciated that improvements and/or modifications may be made without departing from the scope or spirit of the invention.

Industrial Applicabilitv The invention provides a container which dispenses a measured dose of fluid whilst minimising contact of the fluid with the air. It may be used in the photographic industry where chemicals oxidise rapidly, in the food industry where specific quantities of sauces for example need to be dispensed and where the aesthetic properties of the sauce need to be maintained. The container may also be useful in the pharmaceutical and cosmetic industries to dispense specific quantities of creams, pastes, lotions and other substances.