Technical Field of the Invention
This invention relates to dispensers having dividers or fluid reservoirs therein
arranged to at least partially prevent gas or air in the dispensers from being ejected
through dip tubes in the dispenser. The invention further relates to dividers for use in
fluid dispensers, which dividers at least partially prevent mixing of gas/air and fluid in a
dispenser, in use.
Background to the Invention
It is known to provide both pressurized fluid dispensers, and non-pressurized fluid
dispensers which dispense fluid through a nozzle arrangement, and which may include a
dip tube connected to the nozzle arrangement, through which fluid is dispensed.
Nozzle arrangements are commonly used to facilitate the dispensing of various
fluids from containers or vessels. For instance, nozzle arrangements are commonly fitted
to pressurized fluid filled vessels or containers, such as an aerosol canister, to provide a
means by which fluid stored in the vessel or container can be dispensed. In addition, so
called pump and trigger activated nozzle arrangements are also commonly used to enable
the fluid contents of a non pressurized vessel or container to be conveniently dispensed in
response to the operation of the pump or trigger by an operator. Another version that is
much less commonly used uses a pump or trigger to pressurize the air and fluid inside the
container and this pressure can be topped up as the fluid is used up. This effectively
becomes the same as an aerosol canister in use.
A typical nozzle arrangement comprises an inlet through which fluid accesses the
nozzle arrangement, an outlet through which the fluid is dispensed into the external
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SUBSTITUTE SHEET RULE 26
environment, and an internal flow passageway through which fluid can flow from the
inlet to the outlet. In addition, conventional nozzle arrangements comprise an actuator
means, such as, for example, a manually operated pump or trigger or aerosol canister.
The operation of the actuator means causes fluid to flow from the container to which the
arrangement is attached into the inlet of the arrangement, where it flows along the fluid
flow passageway to the outlet.
Many liquors, foams or pastes are delivered using manually operated aerosol
cans, pumps or triggers and they often have a diptube reaching from the top or outlet of
the container to the bottom so that the fluid is drawn from the bottom to the top and out
through the outlet. Sometimes these diptubes are part of the container and can be in the
centre of the container or along a wall of the container especially with plastic containers.
A large number of commercial products can be dispensed this way, including, for
example, tooth paste, antiperspirants, de-odorants, perfumes, air fresheners, antiseptics,
paints, insecticides, polish, hair care products, pharmaceuticals, shaving gels and foams,
water and lubricants.
Most fluids are simply held in the container with air taking up the remainder of
the container with pumps or triggers and air or a propellant taking up the remainder of the
container for aerosols or pressurized containers. This is no problem for most fluids but
some need to be kept separate from the air or in the case of aerosol canisters from the
pressurized propellant which may be air or butane or other alternatives like C02. Some
products like foods can go off and others like shaving gel can expand and become either
unusable or unstable. This also prevents accidental loss of the air or propellant when the
device is used and this can be a problem.
The problem of separating the fluid from the air or propellant has been generally
approached in two different ways. In aerosol cans deformable bags are used in can or via
bags attached to valves. The fluid is kept in a bag inside the canister and the bag is either
sealed around part of the can itself or around the valve in the can and the propellant gas is
inside the can and around the bag. When the outlet valve is opened by depressing the
actuator, the gas pressure acting on the bag forces out the fluid through the valve and
actuator and the bag is compressed. The bags are often made of up to 4 different layers
of material so as to keep the propellant and fluid apart and they are relatively expensive
and the assembly process is generally expensive and complicated. The bags often never
completely empty the contents and 5 - 10% of the fluid tends to remain in the bag.
With pumps and triggers bags are also sometimes used and another approach has
been to use a shaped plate between the fluid and air called "follower plates" as they
follow the fluid as the container empties. These plates seal against the side walls of the
container and are upstream of the fluid in the container usually towards the base. As the
fluid is discharged, the plate moves downstream keeping the fluid chamber filled. For
this to work the walls of the container have to be parallel and the vessel is usually tubular
or oval in shape. The plate is usually shaped to match the shape of the downstream end
or top of the container so as to be able to drive most or substantially all of the fluid out of
the container. If the top of the container is shaped like a standard bottle or container with
a reduced neck on the shoulder then the bottom of the chamber has to be open so the
follower plate can be inserted through the bottom. Alternatively, with a closed bottom
the top of the container has to be the same size and shape as the rest of the container so
the follower plate can be inserted from the top.
Advantages of follower plates include that they are relatively cheaper to make and
assemble than other means described hereinabove. One disadvantage is that they cannot
be used with diptubes or inside aerosol cans or with bottles or containers with smaller
necks and a closed base.
Bags are widely used in pump or trigger containers and they can be a separate bag
that is inserted after the container is made or they can be moulded into the container. The
fluid is put inside the bag and is delivered by being sucked out of the bag by the pump or
trigger collapsing the bag. Air is drawn into the container through a hole or aperture in
the container wall or top and then around the bag as the bag is collapsed and the air is at
atmospheric pressure. Sometimes the bag is made of one plastic or rubber and other
times it is made of layers of different materials depending upon the barrier properties
required to protect the fluid. These systems are generally more expensive than follower
plates although they may be more versatile and standard containers can be used. Bags
tend to be made of layers because they are thin whereas a follower plate tends to be
thicker and made of a stronger, more chemically resistant plastic creating robust barrier.
There are two general types of aerosol cans with one having a seam along the
length of the can and a separate top and bottom joined to the body and the other being
seamless and made from one part which is drawn into shape and a separate top joined to
the body. Known follower plates would not work with seamed containers as there would
be no seal because of the seam. In seamless cans with reduced neck diameters it is not
possible to use a follower plate because of the reduced neck preventing insertion of the
plate and another problem with aerosol cans comprising diptubes is that any diptube
present would be in the way of the follower plate.
It is therefore an aim of embodiments of the invention to provide fluid dispensers
which enable separation of at least some of the air/gas or propellant in a dispenser from
the dispensing liquid and which prevent or reduce leakage of the air/gas or propellant into
a diptube or out of the dispenser. It is also an aim of embodiments of the invention to
provide divider or fluid reservoirs for us in fluid dispensers which can be used in a wide
variety of dispensers and which are robust, relatively inexpensive to make an insert, and
which can be inserted into a wide variety of fluid dispensers including seamed dispensers,
dispensers with reduced diameter necks and aerosols or other pressurized containers.
It is also an aim of embodiments of the invention to overcome or mitigate at least
one problem of the prior art described herein above.
Summary of the Invention
According to a first aspect of the invention there is provided a pressurized
dispenser comprising a base around which surrounds a peripheral wall having an open
end sealed by a dispensing element comprising a dip-tube, a fluid reservoir in contact
with the dip-tube for reducing the compressed gas lost from the pressurized dispenser, a
compressed gas and a dispensing liquid, wherein a majority of said fluid reservoir being
located outside of the diptube and the fluid reservoir comprises a porous material,
arranged in use to hold a volume of the dispensing liquid, the porous material being
configured so that in use at least a portion of any compressed gas in the reservoir can be
displaced by the liquid, ejecting said portion of the compressed gas into the dispenser,
and wherein the dispensing element is configured to dispense the dispensing liquid
continuously for at least 0.5 seconds, upon actuation of the dispensing element.
According to a second aspect of the invention there is provided a pressurized
dispenser comprising a base around which surrounds a peripheral wall having an open
end sealed by a dispensing element comprising a dip-tube or an outlet, a fluid reservoir in
contact with the dip-tube or outlet for reducing the compressed gas lost from the
pressurized dispenser, a compressed gas and a dispensing liquid, wherein the fluid
reservoir comprises a porous material, arranged in use to hold a volume of the dispensing
liquid, and wherein the porous material is configured so that in use at least a portion of
any compressed gas in the reservoir can be displaced by the liquid, ejecting said portion
of the compressed gas into the dispenser.
According to a third aspect of the invention there is provided a method of forming
a pressurized dispenser of the first or second aspects of the invention, the method
comprising the steps of:
a. Providing a dispenser comprising a base around which surrounds a
peripheral wall having an open end; and in any order or together
b. Inserting a porous fluid reservoir as claimed in any one of claims 1 to 33
into the dispenser;
c. Inserting a dip-tube having a fluid inlet end into the open end of the
dispenser; and
d. Adding a dispensing liquid and compressed gas to the dispenser.
According to a fourth aspect of the invention there is a fluid dispenser comprising
a base around which surrounds a peripheral wall having an open end closed by a
dispensing element comprising a dip-tube, the fluid dispenser comprising a divider.
According to a fifth aspect of the invention there is provided pressurized
dispenser comprising a base around which surrounds a peripheral wall having an open
end sealed by a dispensing element comprising a dip-tube, a fluid reservoir in contact
with the dip-tube for reducing the compressed gas lost from the pressurized dispenser, a
compressed gas and a dispensing liquid, wherein the fluid reservoir comprises a porous
material, arranged in use to hold a volume of the dispensing liquid, the porous material
comprising a porous or cellular material having a pore or cell density of at least lOppi
(pores/cells per inch), at least 20ppi or at least 30ppi, and no more than lOOppi or no
more than 80ppi.
According to a sixth aspect of the invention there is a method of forming a
dispenser of any one of the first, second, fourth or fifth aspects of the invention, the
method comprising the steps of:
e. Providing a fluid dispenser comprising a base around which surrounds a
peripheral wall having an open end; and in any order or together
f. Inserting a porous divider of any one of claims into the dispenser; and
g. Inserting a dip-tube having a fluid inlet end into the open end of the
dispenser;
According to a seventh aspect of the invention there is a method of dispensing a
fluid from a fluid dispenser of the sixth aspect of the invention comprising forming a
dispenser, partially filling the dispenser with a dispensing liquid such that at least some of
the liquid enters the porous divider material, partially filling the dispenser with a gas, or
air, and actuating the dispensing element to dispense at least a portion of the dispensing
liquid.
According to a eighth aspect of the invention there is a divider for at least
partially separating a dispensing fluid from a propellant, gas or air in a dispenser, the
divider comprising a resiliently deformable member arranged to be inserted into a
dispenser through one end thereof and move from a first configuration, in which the
divider can be inserted into a dispenser, and a second configuration in which the divider
is able to form at least a partial barrier within the dispenser.
According to a ninth aspect of the invention there is a method of separating a fluid
dispenser into two chambers, the method comprising the steps of:
a. Providing a fluid dispenser comprising a base around which surrounds a
peripheral wall having an open end;
b. Providing a divider of the eighth aspect of the invention;
c. Moving the divider from the second configuration to the first
configuration;
d. Inserting the divider into the fluid dispenser; and
e. Moving the divider to the second configuration to form at least a partial
barrier separating the dispenser into two chambers.
According to a tenth aspect of the invention there is a fluid dispenser comprising a
base around which surrounds a peripheral wall having an open end, and further
comprising a divider of the eighth aspect of the invention, the divider forming two
chambers within the dispenser and being movable up and down the dispenser wall to vary
the size of the chambers, in use.
According to an eleventh aspect of the invention there is a method of dispensing a
fluid from a fluid dispenser of the tenth aspect of the invention comprising:
a. at least partially filling one of the chambers with a dispensing
fluid;
b. filling the other chamber with a pressurized gas or air;
c. operably connecting the dispensing fluid with a dispensing
element; and
d. actuating the dispensing element to dispense the dispensing fluid
and move the divider within the dispenser.
Further aspects of the invention, and features of the various aspects of the
invention are defined in the appended claims.
The eighth to eleventh aspects of the invention provide resiliently deformable
divider or follower plate that will be deformed to enable it to fit through a reduced neck
and reform to function as a standard follower. In some embodiments, the dividers may
have an aperture substantially in the centre that the diptube extends through in such a way
that there is at least one seal between the diptube and divider and this seal is usually an
integral part of the divider. In both cases there may be a seal around the outside of the
divider that seals between the divider and the dispenser, and this seal is usually an
integral part of the divider. The inner and outer seal may both be air tight but loose
enough to enable the divider to move up and down the can as required. The divider may
be resiliently deformable only in certain parts of it or it may all be resiliently deformable.
The divider may be made from a polymeric or natural or synthetic rubber and may be one
component and made of one material but two or more materials or two or more parts of
one or more materials may be used if certain barrier properties are required or part of the
divider could be coated in some way to enhance the barrier properties. For example it
may be painted, coated or even coated or plated with metal on one or more sides.
The divider may be a follower plate.
Two chambers may be created inside the dispenser with one upstream of the
divider and the other downstream of it. The air or compressed gas is normally upstream
of the divider and the fluid downstream of the divider. If no diptube is used then the
downstream chamber may use the outlet as a wall and if a diptube is used the non-outlet
end or the base may used as a wall. With no diptube the divider may moves towards the
outlet end or the top of the dispenser and with a diptube the divider moves towards the
closed end or the base. The divider may be shaped so that it is substantially the same
shape as the end of the dispenser that it moves towards so that all or substantially all of
the fluid may be emptied.
In some embodiments, suitable for fluid dispensers in the form of aerosols the
divider may be positioned on the downstream or closed end of the dispenser (usually the
base), the diptube extends through the central hole in the divider and the or each seal may
touch the downstream end of the dispenser. The upstream end of the diptube may be
shaped so there is a gap around the end of the diptube so the fluid may flow through it.
There may be a top on the dispenser which, in the case of an aerosol, may be located on a
valve in a valve cup, and the diptube may be connected to the valve inlet. Any air
between the downstream wall and the divider may be substantially sucked out. Fluid
may be pumped through the diptube via the valve which is lifted to open it, into the
downstream chamber and the divider may be pushed upstream by the fluid and may
continue to move until all of the required fluid had been added to the chamber. The
diptube may not move and the downstream end of the diptube may then be closed by
releasing the valve so the valve automatically closes.
Air in the upstream chamber may be allowed to evacuate around the valve cup
which would only be fixed in place but not sealed as the downstream chamber is filled
with fluid and the divider moved upstream. Once the fluid chamber is filled there may be
half to two thirds of the dispenser containing air and the fluid chamber may be used for
the pressurized air or propellent or gas. If the dispenser contains air, pressurized air may
be added to the gas chamber by pumping pressurized air under the valve cup and once the
required pressure is achieved the valve may be crimped in place sealing it. If a propellant
such as butane is used instead of air, any remaining air in the upstream chamber may be
removed and then replaced with the required propellant subsequently followed be sealing
the valve cup by crimping as before.
As the fluid is dispensed, the divider may move downstream towards the base
keeping in contact with the fluid, and the valve of gas chamber increases causing a
reduction in pressure of the gas. This process may continue until substantially all of the
fluid has been ejected but there may still be air or gas in the gas chamber and the pressure
of it will depend on the pressure required to eject the fluid. It may normally be between 1
and 3 bars. The action would be the same with a propellant such as butane for example,
while other propellants may maintain a more consistent pressure throughout the working
life of the dispenser.
In alternative embodiments of fluid dispensers of the invention, which comprise
aerosol canisters the fluid may be in the chamber with the outlet wall or valve (now the
downstream chamber) and the air or propellant in the chamber with the base (now the
upstream chamber). With a closed wall or base the divider may start at the outlet end of
the dispenser and there may be no diptube. Any residual air may be sucked out of the
downstream chamber and then the fluid may be added into the downstream chamber
through the valve which pushes the divider upstream towards the base wall of the
dispenser leaving around half to one third of the dispenser inner volume for the propellant
of compressed gas or air. There may be a hole in the upstream container wall or base and
a one way input valve to allow the air or propellant to be pumped into the upstream
chamber. As the fluid is dispensed, the divider may move downstream and the pressure
in the upstream chamber may reduce. One advantage of this embodiment is that there is
no diptube.
In embodiments comprising a pump or trigger the fluid would normally be put in
the upper chamber with the outlet or downstream chamber with the air in the lower
chamber with the base or the upstream chamber. The divider may start at the
downstream end of the dispenser and there may be no diptube. Any residual air may be
sucked out of the downstream chamber and then the fluid may be added into the
downstream chamber to push the divider upstream usually towards the upstream wall of
the dispenser. There may be a hole in the upstream container wall to allow the air or gas
to escape so the remaining air is always at atmospheric pressure. As the fluid is
dispensed, the divider may move downstream and air may be drawn into the air chamber
through the same hole in the chamber wall to maintain atmospheric pressure.
For embodiments comprising a pump or trigger device, the open end of the
dispenser top may be closed with the pump or trigger. As the fluid is dispensed a vacuum
may be created in the fluid chamber causing the divider to move downstream so the fluid
chamber stays full of fluid. This creates negative pressure in the air chamber so air may
enter from outside the dispenser to keep it at atmospheric pressure. This action may
continue until the divider meets the upstream wall having evacuated substantially all of
the fluid.
In embodiments comprising a pump or trigger, the fluid may be put in the
chamber with the base or closed wall (now the downstream chamber) and the air in the
chamber with the opening (now the upstream chamber). The divider may start at the
downstream or base end of the container and there may be a diptube. Initially any
residual air may be drawn out of the downstream chamber and then the fluid added into
the downstream chamber through the diptube and which pushes the divider upstream
towards the upstream wall of the container or open end. There may be a hole or aperture
in the upstream dispenser wall or the top to allow the air to escape so the remaining air or
gas is always at substantially atmospheric pressure. As the fluid is dispensed, the divider
may follow the fluid and air is pulled into the air chamber through the same hole in the
chamber wall to maintain substantially atmospheric pressure.
Suitable material for the divider may be plastics, such as polyethylene or
polypropylene for example, as these are very resistant to many fluids and propellants.
One way of achieving a deformable divider is to use areas or lines of weakness
such as very thin sections, such as annular "V" shaped grooves which enables relatively
easy deformation. Another way would be to use a mixture of porous foaming agent
such as a closed cell material in the divider in combination with a relatively rigid material
like polyethylene or polypropylene so it is both resiliently deformable and chemically
resistant. An alternative would be to use two materials with the first material having a
weakness in the area needed to deform and either over moulding or attaching a more
resiliently deformable material such as a flexible version of the first material or an
elastomer, in this way the chemical barrier may be maintained whilst the mechanical
properties are added with the second material.
In embodiments comprising diptubes in the dispenser may be made from a rigid
plastic material, or from a hard flexible plastics material. Some dispensers may have an
integral diptube in the body of the dispenser and these could be used instead of the
diptube in the follower plate.
One problem with known aerosol canisters particularly with compressed air and
with pumps or triggers is inability to use such aerosols through 360 degrees where
rotation of the canisters may cause the upstream end of a diptube can sometimes be in
contact with the air or propellant instead of the fluid. For aerosols, this can be a major
problem as the gas or air can be lost very quickly resulting in fluid being left in the
canister or very low pressures near the end of the can life and a consequent reduction in
performance. The dividers and dispensers of the invention described above overcome or
mitigate this problem. In the embodiments there may be no need to keep the fluid
separate from the air or propellant but instead is to keep the upstream end of the diptube
always immersed in the fluid regardless of how the dispenser is shaken, tilted or inverted.
Some gas or air can be lost but should be minimized. The divider and diptube
arrangement described above can be used in these applications. It is not essential that any
seals are always maintained as the divider may act as barrier that prevents or reduces a
rapid movement of the fluid away from the upstream end of the diptube when the
dispenser is tilted or shaken and it may be configured so that one or both seals are able to
leak because once the dispenser is left upright the air or propellant and fluid will tend to
return to the uppermost chamber and the fluid to the lower chamber especially in
dispensers where the propellant is pressurized. There may be small holes in the divider to
allow the fluid to return to the downstream chamber. Any gaps in the seal or holes in the
divider should be small enough to ensure that the divider is pushed towards the fluid by
the gas or propellant. This means that the divider may be relatively thin like packaging
used in the food industry or it could be a closed cell foamed divider or even an open cell
foam divider with an impermeable layer or skin on the surface that prevents any fluid
passing through the divider.
The divider may not need to move, and thus the divider may be immovable within
the dispenser. It may be fixed in position, preferably near to the downstream end of the
dispenser with a small chamber formed between the divider and base of the dispenser. A
diptube may pass through the divider and into the chamber which would contain the fluid
to be dispensed. Fluid would be able to pass through or around the divider to replace any
fluid dispensed. The rate that the fluid could enter the chamber would be comparable but
greater than the flow at which it is dispensed as there is always fluid available to be
dispensed. If the dispenser is tilted or shaken the loss of the fluid from the chamber may
be reduced and the amount of air or gas that replaces it is also reduced. Any air or gas in
the small chamber lost whilst the fluid was being dispensed is substantially reduced
compared to the loss with no divider. In addition, once the dispenser is left upright, any
air or gas would move upwards past or through the divider and would be replaced by the
fluid.
In some embodiments the divider is made of a porous material such as foam and
the upstream end of the diptube is located inside the foam. The fluid can now pass
around the divider but would normally pass through it as it is either drawn or pushed into
and through it. There may be no need to seal the divider against the dispenser walls or
even the need to create a chamber between the divider and the base of the dispenser as
the porous material may hold enough of the fluid itself. In some embodiments the
dispenser may have one or more shaped bases or a peak in the base, and comprise a
substantially flat porous divider which contacts the or each peak such that at least one
chamber is formed in each recess extending from the peak. Fluid may be drawn through
the diptube from inside of the porous divider and this causes more fluid to replace it. If
the dispenser is upright then more fluid from above porous divider will be absorbed into
it and the chamber below the divider may be full of fluid and any air or propellant may go
around or through the divider into the chamber above it. If the dispenser is inverted then
fluid will still go from the divider through the diptube and outlet and the fluid inside the
small chamber now above the divider may be absorbed into the foam with air or
propellant replacing it by going through or around the divider. When the container is
angled somewhere between the two extremes of upright and inverted, the fluid will be
touching at least some of the divider and will be absorbed. This may continue until the
small chamber is empty and the fluid has been extracted from the divider but the
dispensers tend to be moved through many angles as they are used so the fluid can
quickly replenish the small chamber. The reservoir of fluid in the chamber and divider is
generally more than enough for the likely usage at any one time which means there is
generally no need to lose much, if any, air or propellant. There is also no need to have a
smaller chamber for many applications and the foam divider may be made large enough
to hold a sufficient volume of fluid. The divider may touch the base or walls of the
dispenser and may be held around the diptube or may be any shape with the diptube
pushed inside it. Generally it may be positioned on or around the upstream end of the
diptube and touching the downstream wall and base of the dispenser. These
embodiments are generally for small dispensers used with products like perfume as the
foam divider can be very small such as a plug or rod on the end of the diptube for
example. For large dispensers a divider in the form of a plug or rod is also useful. In
some embodiments an open cell rod such as a backer rod, used in sealing applications,
may be used.
A porous plug or rod is one solution to a problem because the foam is relatively
cheap; it is easily pushed through a reduced neck in a dispenser and if it is larger than the
neck, it readily reforms. It can be made from many materials including plastics, synthetic
or natural rubber, paper or any other materials that will form a stable porous material and
the porous material can even be made inside the dispenser by spraying or mixing
materials inside the dispenser. Fluid and gas or propellants are able to rapidly flow into it
yet may retain most of that fluid as the dispenser is moved around or shaken. The porous
material naturally absorbs liquid in preference to gas or air and may replace gases with
liquid so there may be very little gas or air lost in practice. Some closed cell foams can
be converted into open cell foams by making holes in the material or the outer layer and
these materials may also be used.
Any suitable absorbent or porous material may be used instead of the open cell
foam described above provided the absorbent material is stable in the dispenser and fluid
environment and that the fluid flows readily through it. Any material that has the
required properties will suffice. Various foam and absorbents may be combined together
for some applications.
Some foams or absorbents are designed to only allow liquids through and to
prevent gas or air and these may also be connected to the end of the diptube or around the
outlet.
Description of the Invention
Further aspects and features of the invention will be understood from the
following description of a number of embodiments of the invention, which are provided
by way of example only, with reference to the accompanying drawings, in which:
Figure 1 is a cross-sectional view though a dispenser of the invention in the form
of an aerosol canister with divider of the invention inside and a diptube.
Figure 2 is a view similar to that of Figure 1 but showing the version with no
diptube.
Figure 3 is a cross-sectional view though a pump dispenser of the invention with a
divider of the invention in the form of a foam plate inside.
Figure 4 is a cross-sectional view though a dispenser of the invention in the form
of an aerosol canister with foam plug divider of the invention inside.
Figure 5 is a cross-sectional view though a dispenser of the invention comprising
a trigger with a foam rod divider inside.
Figure 6 is a cross-sectional view though a dispenser of the invention with a fixed
divider of the invention inside.
Figures 1 and 2 show a pressurized dispenser of the invention in the form of a
pressurized aerosol canister 100 with a divider of the invention in the form of a shaped
dividing or follower plate 120 and diptube 110 in accordance with the invention. The
downstream chamber 103 would contain the fluid to be dispensed and the downstream
wall 101 is the base of the canister which has a wall 102 and reduced opening or neck
105. The upstream chamber wall comprises the neck 105 of the canister and the valve
cup 106. A valve 115 is inserted and sealed in the opening 107 and a valve cup 106 is
crimped and sealed around the neck 105 at 108. The diptube 110 is fixed onto the valve
1 5 onto a neck portion 117 at the downstream end and passes through a hole 123 in the
dividing plate and almost contacts the base 101 at the upstream end 1 1. The propellant
or air is contained in the upstream chamber 104. The dividing plate 120 has two outer
annular seals 121 and 122 that seal against the canister wall 02 and two inner annular
seals 124 and 125 that seal against the diptube 110. The fluid to be delivered is filled
through the valve outlet 116 by lifting up a valve stem 118 to open the valve internally
and pumping the fluid through it and the diptube into a lower chamber 103. The valve
stem is then released closing off the valve and sealing in the fluid. The aerosol valves are
all standard and the workings are not shown here. A divider in the form of dividing plate
120 is put inside the can through the neck 105 of the canister and has to be deformed to
get it inside and then it has to resiliently reform once inside. Sometimes the diptube 110
is inside the divider plate 120 before it is deformed and other times it is put through
afterwards. The dividing plate 120 would normally start touching the base 101 and its
base 126 is shaped to conform to the base 101 of the canister 100 and it would slide up
the diptube 110 and canister wall 102 as the chamber 103 is filled. Normally chamber
103 would then be 50 - 75% of the canister capacity.
The propellant or air would then be pumped under pressure into an upper chamber
104 formed between the neck 105 of the canister and the dividing plate 120. Once filled
the valve cup 106 and canister neck 105 would be crimped together at 108 forming a
permanent seal. The contents of the two chambers cannot mix because of the seals 124,
125, 122 and 121 around the dividing plate 120.
As the fluid is dispensed through an outlet 116 in the valve 15 by depressing an
actuator on the valve stem 118 the dividing plate moves downstream staying substantially
in contact with the fluid. This increases the size of the upstream chamber 104.
Eventually the divider plate 120 contacts the base 101 and by then virtually all of the
fluid in chamber 103 has been evacuated.
The propellant in chamber 104 will often be air or gas and consequently the
pressure in the chamber will reduce as the fluid is dispensed. Sometimes it will be a voc
like butane and will exist in liquid and gas and will maintain a similar pressure as the
fluid is expelled by more liquid turning into gas.
The dividing plate 120 is normally a solid and relatively thin plate but it could be
made in a wide range of materials as required and it could for example, be a closed cell
foam plate which would give it the flexibility to the deformed and pushed through the
reduced opening. Some products made of open cell foam have an impermeable layer or
skin around the outside or are coated so nothing will pass through and these could also be
used.
Fig 1 shows a pressurized canister with an outlet valve 115 but the same
arrangement could equally be used with a non-pressurized container with a pump or
trigger in place of the valve 15, similar to the pump or trigger shown in Figs 3 and 5.
For these embodiments there would a leak hole in the pump or trigger or in the
connection between them and the dispenser which would allow air to be pushed out or
pulled in by the movement of the dividing plate 120 maintaining the air in the upper
chamber 104 at atmospheric pressure. The fluid may be located in the downstream or
lower chamber 103 before the dividing plate is inserted. The pump or trigger pumps
fluid from chamber 103 through the diptube 110 and out of the pump or trigger outlet.
The dividing plate is then drawn towards the base 101 of the container and air is drawn
into the upper chamber 104.
In Figure 2 there is a similar arrangement of an embodiment of a dispenser of the
invention to that of Figure 1 except there is no diptube or corresponding hole in the
dividing plate 220. This time, to fill the canister the fluid is pumped through a valve stem
118 into the top chamber 104 and the divider plate 220 moves away from the top of the
canister near to the valve 115 down towards the base 101 of the canister. The propellant
or air is then added into the lower chamber 103 via a one way valve (not shown) that is
fixed into the hole 201 on the base 101 of the canister and this permanently seals after
filling. As the fluid is discharged by pressing on an actuator on the valve stem 118, the
top chamber 104 reduces in size as the dividing plate moves upwards towards the outlet.
The lower chamber 200 then increases in volume causing the gas pressure in the chamber
to reduce unless a voc propellant is used.
Fig 2 shows a pressurized canister of the invention with an outlet valve but the
same arrangement could equally be used with a non-pressurized container with a pump or
trigger in place of the valve 115, similar to the pump or trigger shown in Figs 3 and 5.
For these embodiments there would a hole 201 in the base or lower walls of the dispenser
but no valve inside it as the hole allows air to be pushed out or pulled in by the movement
of the dividing plate 220 maintaining the air in the lower chamber 103 at atmospheric
pressure. The fluid is put into the downstream or upper chamber 104 after the dividing
plate is inserted and pushed next to the base of the container 101. The pump or trigger
pumps fluid from chamber 104 through their inlet like 219 and out of the pump or trigger
outlet. The dividing plate is then drawn towards the top or outlet of the dispenser and air
is drawn into the lower chamber 103 via the hole 201.
This is true for all of the embodiments of Figures 1 to 6 which could all be used
with pressurized containers including aerosol canisters, or with non-pressurized
containers for pumps or triggers.
Fig 3 shows an embodiment of a dispenser of the invention with a divider of the
invention in the form of a dividing plate or disc 325 which is stationary and positioned
substantially next to the base although it could be higher if required. The plate 325 is
made from a porous material in the form of an open cell foamed or cellular material plate
that absorbs liquid. A diptube 310 is present which has an angled downstream end 311
that is able to penetrate into the foamed plate 325. The dispenser has a single peak
extending from the base 303 and this creates at least one annular chamber 304 between
the base 303 and the plate 325. The container 300 is shown as holding fluid 328 in the
lower half and air 329 in the top half. The foamed plate 325 is saturated with the fluid
and the annular chamber 304 below the plate is also full of it, as is the diptube. The
dispenser includes a pump 320 which is held onto the outlet of the neck 302 of the
container with a threaded top 315 and has an outlet orifice 322. It could also have a
trigger on top or the arrangement could be an aerosol canister with pressurized fluid. As
the actuator 321 is depressed, fluid 328 exits via the orifice 322 and this is drawn from
the container 300 through the foamed plate 325 and through the diptube 310. As fast as
fluid is drawn from the foamed plate 325 it is replaced by fresh fluid that is drawn into
the foam by the gas pressure and normal absorption. With a pressurized canister the
fluid is pushed into the foamed plate 325 by the pressure of the propellant or air 329 and
then through the diptube, and it is also absorbed into the foamed plate 325.
When the dispenser of Figure 3 is tilted or inverted so the fluid tilts or drops to
towards the outlet end 313. The fluid in the open cell foamed plate 325 stays inside the
plate. The fluid in the small chamber 304 tends to stay inside the chamber when the
dispenser 300 is tilted or inverted but some can escape into the plate or around it. When
the dispenser is then turned upright it quickly returns to the original position. If the fluid
is being discharged while the dispenser is being moved around, shaken, tilted or inverted
fluid is drawn from the foamed plate 325 and replaced with other fluid in contact with it
from either chamber so it continues discharging through all angles. Once the dispenser is
then angled back up or is upright, fluid will quickly fill the smaller chamber and the foam
plate 325 and the air will return to the large chamber 329. This is also true of an aerosol
canister and the action is the same, save that the fluid replaces the propellant gas in the
foamed plate and smaller chamber 304 when the dispenser is no longer inverted and the
action is faster because of the propellant being pressurized. But these dispensers are
used substantially upright in normal use and aren't tilted or turn upside down for more
than a short period of time. The foamed plate is made with enough capacity to enable the
fluid to be drawn from it rather than the air or gas and still have some left in the foamed
plate 325 as the dispenser returns to a largely upright position enabling fluid to replace
any air or gas in the foamed plate 325 and preventing the fluid or air being delivered to
the diptube. So if the fluid is delivered slowly through the outlet 322 only a small
volume of foam is required and if it is being delivered quickly a larger volume of foam is
required. Most suitable foams are relatively inexpensive but still need to be minimized
because of price pressure so the small chamber 304 can be a good storage chamber as it
will supply the foamed plate 325 with more fluid when the dispenser is inverted. Even a
small foamed plate 325 enables a user to deliver the fluid and still lose very little air or
propellent. In other embodiments foamed plate 325 may have had part of its base shaped
and extending into or filling the annular groove 303 and the end of the diptube 310 may
be much closer to the base 303 of the dispenser and also angled into the annular chamber
304. The divider plate 325 could be any shaped required and could for example, have a
large hole in the centre largely to reduce the cost with the diptube angled over into the
foam divider plate, or ring as it would become.
The embodiment shown in Fig 4 comprises an aerosol canister 400 similar to that
of Fig 1 (like numerals represent like components) with a plug of cellular material or
foam 401 instead of a divider plate or disc and the plug is on the end of the diptube 110
and inside part of the annular groove 403 does not create a smaller chamber below it.
The plug could be any shape or size or material as required and it could be assembled in
the dispenser or on the diptube and then put inside the dispenser. It could be placed as
shown or in any other position near to the base 404 of the dispenser and it could be raised
above the annular groove 403 creating a gap for fluid under it. Again, an aerosol canister
has been shown but it could also be a pump or trigger with a non-pressurized container.
The diptube 110 includes an inlet hole 11 1 as described above for other embodiments,
but also a secondary hole 406 located partway up the diptube. Both holes 1 1 and 406
are covered by the plug part 401 .
It is often an advantage to deliver additional air or gas to the dispensing liquids
when the canister is emptying and the pressure reducing to improve the quality of the
spray and ideally the lower the pressure and the more empty the canister, the greater the
volume of air or gas added. One way to achieve this in conventional dispensers is to add
more holes in the diptube or a hole further upstream from the end 11 of the diptube.
But this normally causes other problems as when the canister isn't being used and the
level of the liquor is below the hole, the gas or air gets into the diptube through the hole
and displaces much of the liquor in the diptube which is driven out of the bottom of the
diptube. This can represent a substantial loss of air for a compressed air canister and isn't
desirable. The holes are also tiny and are easily blocked especially with the liquor
flowing through them. If the holes are too far away from the end of the diptube then air
or gas is lost sooner than required. The air or gas lost is proportional to the pressure in
the canister yet you actually want more air or gas to be delivered through the hole as the
canister empties. The air or gas can escape through the hole 406 when the canister is
tilted, shaken or inverted if the liquor no longer covers the hole. These are all serious
problems with compressed air aerosols in particular as it is essential to keep the canister
pressure as high as possible. By adding the foam part 401 on the end of the diptube 1 0
as shown in the embodiment of Fig. 4 the tendency for the liquid to be pushed out of the
diptube 110 is reduced so the air or gas is less likely to get inside when the canister 400
isn't being used. The secondary hole 406 also acts as an additional exit route for the
liquid through the foam when the canister is inverted or tilted and this enables more fluid
to be delivered as the forces at the end of the diptube 1 1 is often not sufficient to draw
liquid from all of the foam. Another solution is to add a valve around the hole and this is
achieved with a resiliently deformable band such as an O-ring 408 on a hole 407. The
band 408 is sized so that at low pressures it naturally covers the hole 407 but doesn't seal
it and instead allows a reduced flow through it but at high pressure the additional forces
on the band 408 cause it to seal off the hole 407 allowing no fluid through. The higher
the pressure the more it seals and the lower the pressure the more air or gas it allows
through. This means more air or gas is delivered just when it is needed and the air or gas
used over the canister lifetime can be fully controlled. This can be used with or without
the foam plug part 401 on the end of the diptube 110. It can be positioned anywhere on
the diptube 110 or even around the valve 115 but it is often best used lower down the
diptube so that it only becomes exposed to the gas or air when the canister pressure has
dropped to the level where extra gas or air is needed to be delivered through the hole.
Many different chemicals are used in aerosols and some of these react with the band
making it larger or smaller and this in turn makes it open at different pressures and by
different amounts. It doesn't matter if it opens sooner than ideal if the dispensing liquid
is covering the hole as no air or gas can escape. The lower the band the less the problem
of loss of gas or air to the diptube when the canister isn't being used as it only potentially
becomes a problem when the liquid level is below the hole and that means that relatively
little is lost over the lifetime of the canister. For compressed air aerosols, additional air is
generally only required for the last 20 - 25% of the canister life. The band could also be
put inside the foam if required. A one way valve could be added to the downstream end
111 of the diptube as well as the band to prevent any loss of air or gas when the canister
is stationary as it would fully prevent the escape of any of the liquid in the diptube.
It has been found that an O-ring is a good shape for the band because it seals the hole
more efficiently than a band and it deforms more around the hole as the canister pressures
increases. It also gives a more consistent flow increase with the reducing pressure in the
canister.
In Fig 5 there is provided an embodiment of a dispenser of the invention
comprising a trigger 508 and container 500. A porous foam or cellular material plug 510
is on the end 506 of a diptube 505 and be close to a base 503. Trigger bottles tend to be
large, especially in the base, therefore the foamed plug 510 is mounted to the diptube 505
before assembly. In other embodiments such as spray pumps in the form of perfume
pumps, the dispensers are very small and only a small foam plug may be needed and can
be positioned onto the diptubes. Some aerosol cans are very large and again the same
applies. For most applications with aerosol canisters, pumps and triggers where the fluid
and propellant don't have to be permanently separated, this is an efficient configuration
although the shape of the plug may be different to that described above. It is relatively
simple and cheap and easy to install that the price is relatively low. The diptube may also
be flexible allowing the foamed part to move around under the weight of the dispensing
liquid contained in it so that it will tend to stay immersed in the liquid.
Fig 6 illustrates an embodiment of a dispenser of the invention comprising part of
a container 601 which may be for a trigger, pump or aerosol, and which includes a
diptube 606, and a fixed divider plate 607 with small holes 605, 606 and 607 through the
top surface and partial annular seals 602 and 604. Similar to the small chamber 303 in
the embodiment of Fig 3, there is a chamber between a fixed plate 607 and the base of the
container 601 . The proximity of the plate 607 to the container base determines the size of
the chamber but it would normally be close to the base as in Fig 3. The air or gas as well
as the fluid is free to move from one chamber to the other either through the small holes
in the plate 607 or through the partial seals 602 and 604 which are set to allow some
movement but to slow it down so little gas or air is lost during use.
In general for aerosol canisters and especially those producing an atomised spray
particularly with compressed air or gas propellants, the pressure in the canister when it is
nearly empty is often very low, resulting in a poor spray. It is known that adding some of
this gas or air into the fluid at this time greatly improves the spray quality. Careful
positioning of the diptube in combination with the correct foam size can be used to
enhance the spray quality then because the fluid from the foam will be mixed with the air
or gas in the foam and delivered together. Also, shaping the end of the diptube and its
diameter will also alter the amount of propellant or gas drawn into the fluid. As the fluid
level in the canister reduces so it reduces in the foam and the gas or air will replace it so
when the diptube is exposed to the gas or air. it has a free run from the chamber above
and it will be readily drawn through the diptube along with the fluid. By varying the
foam cell size and the height of the angle of the end of the diptube air or gas that is added
to the fluid can be controlled, enhancing the spray quality. As already described a simple
and effective improvement is to add a hole or holes in the side of the diptube away from
the upstream end of the diptube but still covered by the foamed part as shown in the
Figure 4 embodiment. Holes in diptubes would normally be very small but still allow a
lot of gas or air to escape which is normally too much and by covering the hole with the
foam this is considerably reduced giving the enhanced performance with an acceptable
gas or air loss.
The type of porous or cellular material is important both interiors of material and
what the average cell size is as well as the free space available and the actual size of the
part and the density. A very fine cell structure with small chambers is little use with big
flows of liquor or even with viscous liquids. Equally a coarse cell structure is not
practical for tiny flows such as for perfume pumps. The foam also needs to be able to
retain the fluid when inverted or out of the fluid or when the container is shaken and
many coarse foams don't retain much fluid in those circumstances whereas fine foam
may. Some foams absorb up to IS times their size whereas others only absorb small
volumes. Since it can be used for a wide variety of fluids, delivery systems, flows and
discharge volumes, many types of foam will be used from fine to coarse and with a wide
range of properties and materials. Also, many shapes and sizes of the divider part itself
will be used. The divider part is essentially a reservoir of the fluid so if there is a small
discharge then the fluid reservoir does not need to hold much fluid whereas if there is a
large discharge it does. Also, if the dispenser is used upright for most of the time then the
fluid will keep flowing through the divider and consequently a smaller divider is required
whereas if the divider is often out of the fluid because of the dispenser being tilted and
turned upside down a greater reservoir will be needed and the foamed part will need to be
larger. Open cell foamed dividers may have an impermeable surface and one or more of
the sides of the foamed divider could retain this so that fluid and air or propellent could
only be drawn though the other sides, or part of the surface could be opened up with fine
holes. Some closed cell foams may function like open cell foams if the surface has holes.
In some embodiments the porous or cellular material comprises pores having an
average pore size of at least SO microns, at least 100 microns or at least 200 microns, and
may have a pore size of no more than 1000 microns, no more than 750 microns or no
more than 500 microns.
In some embodiments the fluid reservoir, such as the porous material, may
comprise a material having at least lOppi (pores per inch), at least 20ppi and at least
30ppi, and may have no more than lOOppi, 80ppi, 70ppi or 60ppi.
In some embodiments the fluid reservoir may hold at least 0.5ml of fluid, or at
least 1ml or at least 2ml.
In some embodiments the fluid reservoir holds at least 0.5ml of liquid and has at
least lOppi or at least 20ppi.
One of the problems associated with dispensers with diptubes may be retaining
the divider on the diptube during transportation and assembly so the divider may need to
be permanently fastened to the diptube. This can be done in a variety of ways including
heat welding, ultrasonic welding, fixing with a clip or wire, or fixing part of the skin of a
foam divider instead of the foam itself. For porous foamed dividers preferred method is
to push a pin through the foam divider and the diptube and bending the pin so as to trap
the foam onto the diptube. This is usually done near to the input of the diptube. A staple
or fastener could be used instead of the pin and one or both of the legs could be shaped to
leak around them and this could also be arranged for the pin. Simply shaping or
roughening the surface of the legs would cause such a leak and this could be used instead
of making holes in the diptube under the foam. The staple or pin could be positioned so
as to allow gas or air to escape into the diptube when the dispenser has been used to a set
level such as 80 or 90% to improve the spray quality by fixing it to the appropriate
position on the diptube.
Some absorbents like some foams can be made inside the dispenser and the
diptube pushed into it during assembly and in some cases this may be the better option.
For foam dividers the foam should generally let any air or gas trapped in it to
escape quickly and should and able to tolerate a range of different chemistry.
The volume of the foam may be important as it has to hold enough dispensing
liquid to enable the dispenser to keep discharging liquid when the device is tilted or
inverted or shaken. If the foam is partially immersed in the liquor then it will tend to
draw on that liquor and mat will go to the inlet of the diptube in preference to the gas or
air but as the liquor in the foam is used up so air or gas will be lost along with the new
liquor entering the foam. If the foam does not touch the liquor then as the liquor in the
foam is expelled so the gas or air is lost through the foam. Aerosols deliver liquor at
varying rates between 0.3 - 4 mis per second with 1ml per second being common. So if
there is only a small volume of foam and therefore a small volume of liquid that the foam
can hold then the liquid can quickly be used up and the air or gas will rapidly escape and
it takes a very short amount of time before it become critical. The greater the volume of
foam the better, and generally 1 ml foam would be the minimum needed but it may be
between 3 -20 mis. In terms of the liquid the foam can hold, this may be at least 0.5 mis
and preferably 1 - 3 mis and even more preferably 3 -20 mis.
Foam is measured in pores per inch or "ppi" and the smaller the number the
coarser the foam and the higher the number the finer the foam. The more the pores per
inch and the finer they are the denser the foam. With higher ppi foams such as 90 ppi and
over, the pore size is very small and that makes them suitable for filters but it also
reduces the volume of liquid that they can hold. Conversely, coarser foams below 20 ppi
have very low density foam with large sell sizes that could potentially hold far more
liquid and it flows easily through it but the foam may not be able to retain the liquid if it
isn't immersed in it. A pore size that enables the foam to retain the liquid if the dispenser
is inverted or shaken but that also holds as much liquor as possible should be used. This
also depends on the viscosity of the liquid as higher viscosities can be retained in larger
pore sizes than lower viscosities and the greater the viscosity the greater the cell size
needs to be in order to allow the liquid through. The porous material preferably
comprises more than 10 ppi and most preferably greater than 20 ppi but the average pore
size is preferably less than 120 microns and most preferably less than 90 microns.
Foam materials have been exemplified but any absorbent, cellular or porous
material that allows fluid to flow through freely could be used instead, and the pore sizes,
capacities and ppi described above apply thereto.
With an upright pressurized dispenser the air or gas tends to settle on top of the
liquid present and consequently when the porous material is immersed the pressure of the
air or gas causes the liquid to drive any air or gas out of the material and into the dispnser
replacing the gas with liquid and ensuring that the foam is always full of liquid. This is
also true if the dispenser is tilted anywhere above the horizontal provided the dispenser
isn't substantially empty. Since pressurized canisters are generally always left standing
upright after use this means that the foam will be recharged with liquid after use, but as
this is a very quick action it tends to be recharged during use as well. If the level of the
liquid goes below the top of the porous material then the gas will go to the same position
in the porous material as the top of the liquid, the porous material may also absorb some
liquid moving the air higher. The gas won't tend to go into the diptube because it is full
of liquid and the gas takes the easiest route. In addition to the force of the gas or air
pushing the liquid into the foam and the gas or air out, there is also a natural tendency for
a porous material to absorb the liquid again replacing at least some of the gas or air. The
larger the cell size the easier it is for the liquid to replace the gas or air.
The invention described can be used to produce a spray, foam or bolus of liquid
from pressurized dispenser, or pump or trigger dispensers.
Whereas the invention has been described in relation to what is presently
considered to be the most practical and preferred embodiments, it is to be understood that
the invention is not limited to the disclosed arrangements but rather is intended to cover
various modifications and equivalent constructions included within the spirit and scope of
the invention.

Claim
A pressurized dispenser comprising a base around which surrounds a peripheral
wall having an open end sealed by a dispensing element comprising a dip-tube, a
fluid reservoir in contact with the dip-tube for reducing the compressed gas lost
from the pressurized dispenser, a compressed gas and a dispensing liquid, wherein
a majority of said fluid reservoir being located outside of the diptube and the
fluid reservoir comprises a porous material, arranged in use to hold a volume of
the dispensing liquid, the porous material being configured so that in use at least a
portion of any compressed gas in the reservoir can be displaced by the liquid,
ejecting said portion of the compressed gas into the dispenser, and wherein the
dispensing element is configured to dispense the dispensing liquid continuously
for at least 0.5 seconds, upon actuation of the dispensing element.
A pressurized dispenser as claimed in claim 1 wherein the porous material
comprises a foam or cellular material.
A pressurized dispenser as claimed in claim 2 wherein the foam or cellular
material comprises closed cells, open cells, or a combination of closed or open
cells.
A pressurized dispenser as claimed in any one of claims 1 to 3 wherein the foam
or cellular material comprises cells adapted to allow free flow of liquid through
the cells.
5. A pressurized dispenser as claimed in any one of claims 1 to 4 wherein the
reservoir comprises a polymeric material selected from polyurethane, polystyrene,
polypropylene, polyethylene, polyvinylchloride or a combination thereof.
6. A pressurized dispenser as claimed in any one of claims 1 to 5 wherein the porous
material is a sintered material or an injection-moulded material.
7. A pressurized dispenser as claimed in any one of claims 1 to 6 wherein the porous
material is a resilient and/or deformable material.
8. A pressurized dispenser as claimed in any one of claims 1 to 7 wherein the porous
material is an inflexible material.
9. A pressurized dispenser as claimed in any one of claims 1 to 8 wherein the
reservoir holds at least 0.5ml, at least 1ml or at least 2ml of dispensing liquid.
10. A pressurized dispenser as claimed in claim 9 wherein the reservoir holds at least
Sml of dispensing liquid.
11. A pressurized dispenser as claimed in any preceding claim wherein the porous
material comprising at least lOppi (pores per inch), at least 20ppi or at least 30ppi.
12. A pressurized dispenser as claimed in any preceding claim wherein the porous
material comprises no more than 80ppi, no more than 7Sppi or no more than
70ppi.
13. A pressurized dispenser as claimed in any preceding claim wherein the porous
material comprises at least 20ppi and holds at least 0.5ml of dispensing fluid.
14. A pressurized dispenser as claimed in any preceding claim having a storage
capacity of between 10ml and 5000ml, or between 20ml and 1000ml.
15. A dispenser as claimed in any preceding claim wherein the reservoir forms a
barrier within the dispenser through which the dip-tube extends, the dip-tube
having a fluid inlet end located at or near the base of the dispenser.
16. A dispenser as claimed in claim 15 wherein the reservoir is located at or near the
fluid inlet end of the dip-tube.
17. A dispenser as claimed in claim 16 wherein the reservoir covers the fluid inlet end
of the dip-tube.
18. A dispenser as claimed in claim 17 wherein the reservoir forms a plug at the end
of the dip-tube comprising the fluid inlet.
19. A dispenser as claimed in claim 7 or 18 wherein the dip-tube comprises a fluid
inlet at an end thereof, and a second fluid inlet located along the length of the diptube,
and the reservoir covers both fluid inlets.
20. A dispenser as claimed in any one of claims 14 to 19 wherein the reservoir is
fixedly connected to the dip-tube.
2 1. A dispenser as claimed in any one of claims 14 to 20 wherein the reservoir spans
the fluid dispenser dividing the dispenser into two chambers.
22. A dispenser as claimed in claim 21, comprising a dip-tube having a fluid inlet
end, wherein the fluid inlet end is located below the reservoir, at or near the base
of the dispenser.
23. A dispenser as claimed in claim 1 or 22 wherein the base of the dispenser
comprises at least one peak, and the reservoir contacts the peak such that at least
one chamber is formed in the or each recess extending from the or each peak.
24. A dispenser as claimed in any preceding claim wherein the gas is compressed air
or a propellant.
25. A dispenser as claimed in any preceding claim wherein the reservoir is a foam or
cellular material and the cells of the foam or cellular material are adapted to retain
liquid within the cells when the dispenser is inserted, tilted, shaken or any
combination thereof.
26. A dispenser as claimed in claim 25 wherein the cells are sized to retain at least
0% vol of a liquid present in the fluid dispenser, or at least 20% vol, at least 50%
vol or at least 60% vol.
27. A dispenser as claimed in any one of any preceding claim wherein the reservoir is
a foam or cellular material having any suitable density.
28. A dispenser as claimed in any preceding claim wherein the reservoir comprises a
foam or cellular material having any suitable cell size.
29. A dispenser as claimed in any one of claims 14 to 28 comprising an aerosol
comprising compressed gas or air.
30. A dispenser as claimed in any preceding claim wherein the dispensing element is
configured to dispense at least 1ml, at least 2ml or at least 5ml upon actuation.
31. A dispenser as claimed in any preceding claim, wherein the dispensing element is
configured to dispense no more than 20ml, no more than ml or no more than 10
ml upon actuation.
32. A dispenser as claimed in any preceding claim, wherein the porous material
comprises pores having an average pore size of at least 50 microns, at least 100
microns or at least 200 microns.
33. A dispenser as claimed in any preceding claim, wherein the porous material
comprises pores having an average pore size of no more than 1000 microns, no
more than 750 microns or no more than 500 microns
34. A method of forming a pressurized dispenser of any preceding claim, the method
comprising the steps of:
a. Providing a dispenser comprising a base around which surrounds a
peripheral wall having an open end; and in any order or together
b. Inserting a porous fluid reservoir as claimed in any one of claims 1 to 33
into the dispenser;
c. Inserting a dip-tube having a fluid inlet end into the open end of the
dispenser; and
d. Adding a dispensing liquid and compressed gas to the dispenser.
35. A method as claimed in claim 34 wherein step (b) is performed after step (c).
36. A method as claimed in claim 34 wherein step (b) is performed before step (c).
37. A method a claimed in any one of claims 34 to 36 wherein the porous fluid
reservoir is added as reactants or pre-cursor ingredients and formed into a foam
within the dispenser.
38. A method as claimed in any one of claims 34 to 37 wherein the method further
comprises connecting a dispensing element to the dip-tube.
39. A method as claimed in any one of claims 34 to 38 wherein step (b) comprises
connecting a resilient or deformable fluid reservoir inside the dispenser to form at
least two chambers separated by the fluid reservoir.
40. A method as claimed in any one of claims 34 to 39 wherein step (b) comprises
connecting the fluid reservoir to the dip-tube before inserting the dip-tube into the
dispenser.
41. A method as claimed in claim 40 wherein step (b) comprises covering the inlet
end of the dip-tube with the divider before inserting the dip-tube into the
dispenser.
42. A method as claimed in claim 4 1 wherein the dip-tube has more than one inlet
and step (b) comprises covering all of the inlets of the dip-tube with the fluid
dispenser before inserting the dip-tube into the dispenser.
43. A method as claimed in any one of claims 34 to 42 wherein the base of the
dispenser comprises at least one peak and the fluid dispenser is inserted such that
it rests on at least one peak of the base.
44. A method of dispensing a fluid from a pressurized dispenser of any one of claims
1 to 33 comprising forming a dispenser by the method of any one of claims 34 to
43, partially filling the dispenser with a dispensing liquid such that at least some
of the liquid enters the porous fluid reservoir material, partially filling the
dispenser with a compressed gas, and actuating the dispensing element to
dispense at least a portion of the dispensing liquid.
45. The method of claim 44 wherein the compressed gas is at least partially prevented
from being entrained in the porous material and therefore at least partially
prevented from exiting the dispenser as the liquid is dispensed.
46. A pressurized dispenser comprising a base around which surrounds a peripheral
wall having an open end sealed by a dispensing element comprising a dip-tube, a
fluid reservoir in contact with the dip-tube for reducing the compressed gas lost
from the pressurized dispenser, a compressed gas and a dispensing liquid, wherein
the fluid reservoir comprises a porous material, arranged in use to hold a volume
of the dispensing liquid, the porous material comprising a porous or cellular
material having a pore or cell density of at least lOppi (pores/cells per inch), at
least 20ppi or at least 30ppi, and no more than lOOppi or no more than 80ppi.
47. A pressurized dispenser comprising a base around which surrounds a peripheral
wall having an open end sealed by a dispensing element comprising a dip-tube, a
fluid reservoir in contact with the dip-tube for reducing the compressed gas lost
from the pressurized dispenser, a compressed gas and a dispensing liquid, wherein
the fluid reservoir comprises a porous material, arranged in use to hold a volume
of the dispensing liquid, the porous material holds a volume of at least O.Sml, at
least 1ml, at least 2ml or at least Sml.
48. A divider for at least partially separating a dispensing fluid from a compressed
gas or air in a dispenser, the divider comprising a resiliently deformable member
arranged to be inserted into a dispenser through one end thereof and move from a
first configuration, in which the divider can be inserted into a dispenser, and a
second configuration in which the divider is able to form at least a partial barrier
within the dispenser.
49. A divider as claimed in claim 48 wherein the divider includes at least one area or
line of weakness, about which the divider may be moved between the first and
second positions.
0. A divider as claimed in claim 48 comprising at least two areas or lines of
weakness, or any combination thereof.
51. A divider as claimed in any one of claims 48 to 50, wherein the divider is formed
of a resilient material and the divider is movable between the first and second
positions by deforming the resilient material.
52. A divider as claimed in any one of claims 48 to 5 1 formed of a single, unitary
member.
53. A divider as claimed in any one of claims 48 to 52 formed of multiple pieces
connected together.
54. A divider as claimed in claim 53 wherein the multiple pieces comprise resilient
joins, about which the divider is movable between the first and second
configurations.
55. A divider as claimed in any one of claims 48 to 54 comprising a natural or
synthetic rubber, resilient or deformable polymeric material or any combination
thereof.
56. A divider as claimed in claim 55, wherein the divider consists essentially of
natural or synthetic rubber, resilient or deformable polymeric material, or any
combination thereof.
57. A divider as claimed in any one of claims 48 to 56 wherein the divider includes at
least one aperture therethrough arranged in use to receive a dip-tube.
58. A divider as claimed in claim 57 wherein the divider comprises a dip-tube
extending through the aperture.
59. A divider as claimed in claim 58 wherein the divider is movable up and down the
dip-tube.
60. A divider as claimed in any one of claims 57 to 59 wherein the divider comprises
a sealing material, arranged in use to form at least a partial seal between the
divider and a dip-tube inserted through the aperture.
61. A divider as claimed in any one of claims 48 to 60 wherein the divider comprises
a sealing material, arranged in use to form at least a partial seal between the
divider and a dispenser in which it is located, in use.
62. A divider as claimed in claim 6 wherein the sealing material is located on the
portions of the divider arranged to contact the wall or walls of a dispenser in
which it is located, in use.
63. A divider as claimed in any one of claims 60 to 62 wherein the sealing material
comprises natural or synthetic rubber, resilient or deformable polymeric material,
or any combination thereof.
64. A divider as claimed in any one of claims 48 to 63 wherein at least a portion of
the divider comprises a material which prevents or reduces movement of gases
across the divider.
65. A divider as claimed in claim 64 wherein the divider is at least partially coated
with a gas-impermeable material.
66. A divider as claimed in claim 65 wherein the gas-impermeable material comprises
a metal or metal-containing material.
67. A method of separating a fluid dispenser into two chambers, the method
comprising the steps of:
a. Providing a fluid dispenser comprising a base around which surrounds a
peripheral wall having an open end;
b. Providing a divider as claimed in any one of claims 48 to 66;
c. Moving the divider from the second configuration to the first
configuration;
d. Inserting the divider into the fluid dispenser; and
e. Moving the divider to the second configuration to form at least a partial
barrier separating the dispenser into two chambers.
68. A method as claimed in claim 67 wherein the open end of the dispenser has a
reduced diameter compared to the peripheral wall.
69. A method as claimed in claim 67 wherein the divider is movable up and down the
fluid dispenser wall when in the second configuration.
70. A method as claimed in any one of claims 67 to 69 wherein the divider comprises
an aperture therethrough and the method comprises inserting a dip-tube through
the aperture before, during or after insertion of the divider into the fluid dispenser.
71. A method as claimed in claim 70 wherein the dip-tube is part of a trigger sprayer,
spray nozzle, spray pump or dispenser head.
72. A method as claimed in claim 70 or 7 1 wherein the divider comprises a sealing
material around the edge of the aperture, arranged to form a seal between the
aperture and dip-tube.
73. A method as claimed in any one of claims 70 to 72 wherein the divider is movable
up and down the dip-tube.
74. A method as claimed in any one of clams 67 to 73 wherein the fluid dispenser is a
pressurized or non-pressurized fluid dispenser.
75. A method as claimed in any one of claims 67 to 74 wherein the method further
comprises at least partially filling one chamber of the fluid dispenser with a
dispensing fluid.
76. A method as claimed in claim 75 wherein the method comprises at least partially
filling the fluid dispenser with a dispensing liquid after the divider is inserted into
the dispenser.
77. A method as claimed in claim 75 or 76 when dependent on any one of claims 64
to 68, wherein the dispensing liquid is inserted through the aperture or dip-tube.
78. A method as claimed in claim 76 or 77 wherein the dispensing liquid is placed on
top of the divider.
79. A method as claimed in claim 75 wherein the dispensing liquid is added to the
fluid dispenser before insertion of the divider into the fluid dispenser.
80. A method as claimed in any one of claims 75 to 79 wherein a pressurized gas is
added to the fluid dispenser.
81. A method as claimed in claim 80 wherein the pressurized gas is added to the
chamber of the fluid dispenser which does not contain a dispensing liquid.
82. A method as claimed in claim 8 1 wherein the dispensing liquid is added to the
fluid dispenser before addition of the pressurized gas.
83. A method as claimed in claim 82 wherein the pressurized gas is added to the fluid
dispenser before addition of the dispensing liquid.
84. A fluid dispenser comprising a base around which surrounds a peripheral wall
having an open end, and further comprising a divider as claimed in any one of
claims 48 to 66, the divider forming two chambers within the dispenser and being
movable up and down the dispenser wall to vary the size of the chambers, in use.
85. A fluid dispenser as claimed in claim 84 wherein the open end has reduced
diameter compared to the peripheral walls and which may be formed as a neck
portion of reduced diameter.
86. A fluid dispenser as claimed in claim 84 or 85 wherein the open end of the
dispenser comprises a dispensing element.
87. A fluid dispenser as claimed in claim 86 wherein the dispensing element
comprises a nozzle, pump trigger sprayer or dispenser head.
88. A fluid dispenser as claimed in any one of claims 8 1 to 84 wherein the fluid
dispenser comprises a dispensing fluid on one side of the divider and a gas on the
other side of the divider.
89. A fluid dispenser as claimed in claim 85 comprising a dip-tube extending through
the divider and having an fluid inlet, and wherein the dispensing fluid is located
on the side of the divider comprising the dip-tube inlet.
90. A method of dispensing a fluid from a fluid dispenser of any of claims 84 to 89
comprising:
a. at least partially filling one of the chambers with a dispensing fluid;
b. filling the other chamber with a pressurized gas or air;
c. operably connecting the dispensing fluid with a dispensing element; and
d. actuating the dispensing element to dispense the dispensing fluid and
move the divider within the dispenser.
91. A method as claimed in claim 90 wherein the dispenser comprises a dip-tube
connected to the dispensing element and step (d) comprises inserting the inlet of
the dip-tube into the dispensing fluid.
92. A divider, fluid dispenser or method as substantially described herein with
reference to the accompanying drawings.
93. A dispenser as claimed in any one of claims 1 to 33 wherein the fluid reservoir
has substantially the same refractive index as the dispensing fluid.