This invention relates to a liquid container and in particular a
container for carbonated beverages such as beer, sparkling wines and soft drinks
such as colas and tonic.
It is known to provide containers for carbonated beverages such as
aluminium or steel cans and bottles manufactured from glass or a plastic material
such as PET. The beverages contain a dissolved gas such as CO2. The
CO2 may be present in the beverages as a result of the manufacturing
process such as brewing in the case of beer or may be dissolved into the liquid
such as usually the case with soft drinks. Containers for such beverages must
be capable of physically withstanding the pressure of the gas, that is, they must
not rupture or creep under pressure and they must also contain the gas without
allowing it to escape from the container. An acceptable shelf life for a beverage
so contained is approximately three months. Current containers such as glass or
plastic bottles and cans do provide the necessary shelf life however there are
drawbacks with such existing containers.
Cans, and in particular aluminium cans, can be recycled however such
recycling requires a relatively large input of energy and further requires that
the containers be sorted and transported to a recycling plant. Cans, even recent
aluminium cans, still require the use of several grams of metal. Another drawback
of cans is that the outer surface thereof is difficult to provide printing on.
Various screenprinting techniques exist, however these are somewhat limited and
in many cases the graphics capable of representation on the outer wall of an aluminium
can are limited to simple designs of primary colours.
In the case of bottles whether of a plastics material or glass printing
directly onto the outer surface of such a container is not normally possible. A
further layer must be provided in order to enable the graphics to be printed.
This complicates the manufacturing process and requires a separate layer of material
which may be dissimilar to the material of the main body of the container thus
The present invention provides a container for carbonated beverages.
These beverages may comprise beer, fizzy wine or other drinks such as soft drinks.
Existing containers do provide for adequate material strength and provide a gas
barrier so that any dissolved gas does not pass out of the container. Existing
techniques such as providing a glass or PET material bottle do adequately contain
such beverages however they do have limitations in that in order to recycle them
a collection facility must be provided and such containers are relatively bulky
and somewhat heavy. There is a further drawback in using PET in that recycled
PET cannot be placed in contact with food so when constructing a container from
recycled PET a layer of virgin PET must be provided on the internal surface which
will contact the beverage with the regrind or recycled PET providing the outer
layer. Card made from plant or vegetable-based material such as using the fibres
of flax, wood or hemp is readily recyclable or disposable. For example it can be
composted, burnt or recycled in a standard paper or card recycling plant. Card
may also be readily printed with detailed graphics. Card has a further advantage
in that it is substantially opaque and beverages such as beer have been found to
keep better when kept out of contact with light. As can be seen from the figures
preferred forms of the present invention as shown in Figure 1 provide a full opening
container, that is, when the endcap is removed full access to the container is
provided. This provides a container of beverage which is easier to drink from as
opposed to current aluminium or steel cans in which a smaller, that is, less than
full aperture opening is provided.
Card such as card produced from vegetable matter, for example, wood
pulp, hemp or flax material does provide a matt surface which can be readily printed
upon. However a single ply of card does not provide a sufficient degree of dimensional
stability, that is, it creeps under pressure. Further, card does not provide for
a sufficient gas barrier to contain gas present within a container manufactured
therefrom. Current card containers such as the "Tetrapak Tetrabrick" can be used
to contain beverages which are non-carbonated. However due to the current technique
of manufacturing the joints of the container are not mechanically strong enough
to withstand any degree of internal pressure. The shape of the container is also
not suitable for carbonated beverage containment.
A container for non-carbonated liquids is described in U.S. patent
5622308, the container walls being formed from a cardboard layer to which a barrier
layer has been laminated, the barrier layer being adhered to the card over its
In U.S. patent 4525396, there is described a container for carbonated
beverages constructed from paper or card, with a gas barrier layer permanently
attached to both faces of the card to form a three-ply laminated structure.
The strength of the bond between the gas barrier layer and the card
is fundamental to the integrity of the finished container of in both of these prior
In European patent 0166667, there is described a container having
a cardboard side or and metallic end caps crimped to the sidewall. The recycling
of such a container is time-consuming, in that separation of the metallic end
caps from the card sidewall is necessary.
The current invention attempts to overcome the problems of the above-mentioned
known devices by providing a container primarily of a vegetable matter card or
paper which provides sufficient dimensional stability and a gas barrier to provide
gas impermeability to enable the container to be used to contain carbonated beverages,
the gas barrier being removable from the vegetable matter components for recycling.
Exemplary embodiments of the present invention will now be described
with reference to the accompanying drawings.
Figure 1 shows a vertical cross-section through a preferred form
of the present invention. The beverage container 1 provides an outer wall 2 of
a card material such as card produced from vegetable matter and further includes
an internal membrane 3. The internal membrane 3 is preferably of a plastic material
such as nylon, polyethylene or PET. In the preferred form of the invention as
shown in Figure 1 a conical end cap 4 is provided over the top of the container.
There may also be present a further cap 5 which is flat-ended.
Figure 2 shows a container according to the present invention without
the internal membrane. This figure shows a vertical cross-section and illustrates
the structure of the outer wall of the container including the bottom endcap 6.
Figure 3 illustrates the construction of the side wall of the beverage
container and shows a preferred laminated structure. In this form of the invention
there are present four layers 10, 11, 12 and 13. These layers are produced from
pieces of card which are arranged concentrically. The joints of the card 20, 21,
22 and 23 are most preferably butt joints, that is, the card is curved and joined
end-to-end. In the preferred form of the invention which utilises four layers the
joints 20, 21, 22 and 23 are offset from each other by 90°. This ensures that
in this form of the invention there are three unbroken layers of card either above
or below each joint.
Figure 4 shows the construction of an endcap according to a preferred
form of the invention. This endcap is constructed from a series of nested cones.
These cones 30, 31, 32 and 33 preferably are produced from a circular piece of
card which has a sector removed. It has been found that a cone angle of approximately
120° provides for adequate strength. A series of extensions or tabs 40 are preferably
provided on the uppermost cone in order to facilitate fixing of the endcap to the
Figure 5 shows a horizontal cross-section showing the expanded layers
in a preferred form of the invention. These layers include butt joints which are
offset from each other by 90°.
Figure 6 shows another form of the present invention in which three
layers of card are provided. The butt joints of this form are offset from each
other by 120°.
Figure 7 shows another form of conical endcap, this form being produced
from triangular segments.
Figure 8 shows a form of the sidewall of the present invention. This
sidewall is approximately cylindrical and thus provides for ease of manufacture
in that the various layers or plies of the sidewall are substantially rectangular
Figure 9 shows a perspective view of another form of sidewall. In
this case the shape is substantially frustoconical having a larger upper opening
and smaller lower opening. This form of the present invention is still relatively
easy to manufacture and provides a further advantage in that it approximates the
shape of a traditional glass.
Figure 10 shows another form of the present invention being a frustoconical
shape having a smaller upper opening and larger lower opening.
Figures 12 to 16 show various possible shapes for the sidewall of
a container according to the present invention.
Figure 11 shows a horizontal cross-section through a preferred form
of the invention in which the cross-section is circular.
Figure 12 shows another shape which is possible for a sidewall when
viewed in cross-section, this shape being a tround. A tround shape has the advantage
of providing for ease of indexing, that is, a series of containers of such a shape
can be conveyed along a path or through an opening with ease.
Figure 13 shows another and less preferred form of the present invention
in which a polygon, in this case a pentagon, is constructed from a series of separate
sidewall pieces 60, 61, 62, 63 and 64.
Figure 14 shows a polygon shape, again a pentagon, in which the sidewall
is constructed from a single piece of material. Such a construction would involve
a number of plies of material similar to the construction of the circular cross-section
sidewall described earlier.
Figure 15 shows another possible cross-section, in this case an octagon
having unequal side lengths.
Figure 16 shows another less preferred technique of constructing
the sidewall of a beverage container, in this case the material is arranged in
a spiral or convolute. That is, a single piece of material is provided which is
wound into an approximately circular shape.
Figure 17 shows the preferred form of the invention utilising concentric
plies of material.
Figure 18 shows yet another form of the invention in which the sidewall
is constructed from a helically wound piece of material 70. Such a technique is
known for the construction of inner cores of, for example, toilet paper. In this
form of the present invention a number of plies of material, for example four,
are provided, the joints of each ply being butt-jointed to each other and the
joints of each separate ply being offset from each other by approximately equal
Figures 19, 20, 21 and 22 show in cross-section various forms of
jointing in providing the sidewall of the present invention.
Figure 19 shows the preferred form in which a butt joint is provided
and the material plies are adhered to each other by a suitable adhesive, for example,
polyvinyl acetate (PVA) glue or another food-approved adhesive.
Figure 20 shows another preferred technique in which the joints are
skived, that is, the joint is similar to the butt joint however the pieces of material
to be jointed to each other are angled. This technique has the advantage of providing
a greater surface area for the ply to adhere to itself.
Figure 21 shows another possible form of joint in which the ply is
Figure 22 shows a preferred jointing technique in which, similar
to that illustrated in Figure 25, an overlap joint is provided however this is
further sealed by a separate layer, for example tape 80.
Figure 23 shows a construction technique of a sidewall according
to the present invention. This involves the layering of a ply onto a former 100.
As illustrated in Figure 27 the former 100 may comprise a cylinder and the various
plies making up the sidewall are simply layered onto the cylinder as it rotates.
The offset of the joints between the plies or layers is achieved by starting the
separate plies at points offset from the underlying joint.
Figure 24 shows a similar technique used to provide a container which
is tround in cross-section. In this case the former 101 is of course of a tround
shape. Other formers may be used to provide various sidewalls of differing shapes.
The present invention provides a container for a carbonated beverage
1 which utilises multiple layers of differing materials. One of those layers 2
comprises one and preferably multiple plies of a plant fibre-based material. Such
a plant fibre-based material may comprise card produced from wood fibres according
to any of the well-known card or paper-making techniques. It has been found that
multiple layers of wood fibre card of approximately 90 grams per square metre in
weight can provide sufficient strength to contain a carbonated beverage when such
material is layered or laminated. Other suitable plant fibre-based materials such
as hemp or flax fibre-based cards may also be utilised. The outer surface of the
sidewall 2 provides an area onto which graphics may be printed. The use of material
of a plant fibre-based nature enables a number of the known techniques for printing
onto plant fibre-based materials to be utilised.
Most plant fibre-based materials are not moisture-proof to any great
degree and therefore the outer surface of the sidewall 2 of the container for carbonated
beverages may be coated with a waterproofing material such as a plastic material
or a wax. Such a layer provides a degree of protection for the sidewall and may
therefore allow for longer shelf-life.
The membrane barrier material 3 which is the internal layer of the
container for a carbonated beverage may be produced from a number of suitable materials.
It may comprise a laminated or multilayer material. Suitable materials have been
found to include nylon or polypropylene or polyethylene or polyethylene napthalate.
Such materials may further include, for added protection, a thin layer of metal
such as aluminium. Devices according to at least preferred forms of the present
invention have been found to be capable of containing pressures of up to 40-75
pounds per square inch. The containment of such pressures was stable over the
intended shelf-life of typical carbonated beverages, that is, over three months.
In preferred forms of the invention, for example as illustrated in Figure 1, the
internal pressure of the carbonated beverage has the effect of tightening the
bond of the upper endpiece 4 to the sidewall 2. This is also the case in forms
of the invention where the outer edges of the topmost piece 4 are rolled together
with the upper portions of the sidewall 2 or the folded skirt portion 13 of the
sidewall 2. In such situations it may be beneficial to provide means for releasing
the pressure contained prior to opening. For example a weakened portion may be
provided on the endcap 4, the user removing the weakened portion by, for example,
pushing or pulling off the weakened portion thereby releasing the pressure and
therefore decreasing the bonding of the upper endcap 4 to the sidewalls 2 thus
facilitating opening. In forms of the invention such a weakening may comprise the
middle or upper portion of the conical endcap 4 which may be either scored, that
is, perforated in such a way as to enable a central portion thereof to be removed
or may comprise a separate conical subportion which can be removed.
In preferred forms of the invention the gas barrier material 3 need
not provide any great degree of pressure containment of the carbonated beverage.
It therefore may be relatively thin as long as it provides the necessary degree
of gas impermeability. It has been found that a container for carbonated beverage
constructed according to a preferred form of the invention provides a container
in which the membrane 3 provides approximately 2-5% of the total mass of the container.
This is an advantage in that the barrier material 3 is likely to be more expensive
and in most cases much more expensive than the material of the outer wall 2.
The degree of attachment of the barrier material 3 to the sidewall
2 need not be great. To some degree the internal pressure of the carbonated beverage
within the membrane 3 will push it against the sidewall 2. In preferred forms
of the invention the membrane material 3 may be easily removed from the sidewall
after disposal of the container. This enables the barrier material 3 to be separately
processed or recycled whereas the sidewall 2 may be subject to different disposal
options. For example the barrier material 3 may be floated off recycled and the
outer wall or layer 2 may be otherwise disposed of for example being a plant fibre-based
material it may be used in landfill, burnt or composted.
As shown in the preferred form of the invention as illustrated in
Figure 1 the removal of the endcap 4 of the container for carbonated beverage provides
a full aperture opening. That is the top of the container is fully open and the
beverage contained therewithin can be readily consumed. However in other less preferred
forms of the invention the endcap may be provided with points of weakening or
for example a tear-tab which the user can remove in order to obtain access to the
beverage contained therein through an aperture which does not occupy the full
end of the container.
The preferred form of the invention as shown in Figure 1 may be further
provided with an additional overcap 5. Such an overcap may be simply a cylinder
closed at one end which fits over the conical endcap 4. This additional overcap
further protects the endcap 4. This is particularly important if the endcap 4 has
as described previously a point of weakening or tear-tab to enable non-full aperture
access to the beverage to be obtained. An additional use of the additional endcap
4 is to enable promotional material such as instant win tickets to be placed under
the outer endcap 5. Until purchased such promotional material would not be visible,
however once purchased a user would be able to remove the outer endcap 5 and view
the promotional material.
The present invention provides containers for carbonated beverages
which may prove attractive to beverage producers for a number of reasons as described
above. Additionally such a container for carbonated beverage is less likely to
cause injury if thrown at persons. This may prove an advantage.
The endcap 4 may be secured to the sidewall 2 by a number of means.
In the preferred forms of the invention as illustrated the conical endcap 4 includes
a skirt portion comprising a substantially cylindrical band of material extending
from the outer surface of the cone. This may prove to be a preferred alternative
to the form of the endcap as shown in Figure 4 which includes a number of tabs
40. It is believed that the endcap of a conical nature as shown in Figure 4 will
be preferred when used as a lower occlusion as shown in Figure 1 and indicated
by the reference numeral 9 whereas the form of endcap comprising a cone with an
additional skirt or cylindrical wall will be preferred when used as a top endcap
as shown in Figure 1. In forms of the invention the sidewall 2 may be rolled or
folded outwardly to provide an upper lip 13 to the sidewall 2. The upper endcap
4 may additionally be provided with a folded or rolled internal lip 14. The metallised
layer, for example the layer of aluminium, is extremely thin, up to approximately
6 microns and maybe less in thickness. The metal layer may be coated with a plastic
or other polymer material. Various techniques exist in the art to which this invention
relates to enable such a thin layer of metal to be bonded with a membrane such
as a plastic membrane.
Such metallised layers are flexible, provide a degree of thermal
insulation and may also enhance the gas impermeability of the membrane. As shown
in Figure 1 the lips 13 and 14 may be sized so as to secure the endcap 4 to the
sidewall 2. In other forms of the invention the skirt of the endcap 4 may be provided
with points of weakening or a tear strip to enable the user to readily remove
the endcap from the beverage container. In other forms of the invention the endcap
4 may be secured to the sidewalls 2 by means of serrations which are provided
inside the skirt of the endcap 4 and on the outside of the sidewall 2. Such serrations
may be of a plastic material and provide for the endcap to click or clip onto
the sidewall. Other forms of the invention may provide an endcap 4 which can be
screwed or twisted off the sidewall 2. The lower endcap 9 may in less preferred
forms of the invention be of a similar form to that as described in relation to
the upper endcap 4. However preferably it is mounted internally in the sidewall
2. This means that the endcap 9 may be positioned such that the point of the cone
may be no lower than the lower portions of the sidewall. This can provide a stable
base for the beverage container. The lower endcap 9 may be adhered inside the
sidewall 2 by means of the tabs 40. A suitable food-grade or food-approved adhesive
such as PVA may be used.
Figure 3 shows various layers of sidewalls. In this form of the invention
the layers 20, 21, 22 and 23 are separate plies of plant fibre-based material card.
As shown in the figures the ends of the various plies are butted together and
joined at their ends. These joints are preferably glued using a suitable food-grade
or food-approved adhesive such as PVA and the joints are offset from one another,
in this case as four layers are provided the offset is 90°. In forms of the invention
wherein three layers are provided the joints are offset by 120°. The various plies
or layers are laminated to each other using again a suitable food-grade or food-approved
adhesive such as PVA.
In preferred forms of the invention the layers may comprise the same
material, for example they may all comprise a wood pulp paper. In other forms of
the invention differing plies or layers may be utilised. For example one layer
may comprise recycled plant fibre-based card whereas other layers may comprise
virgin or non-recycled fibre-based card. In other forms of the invention the orientation
of the fibres may differ in the various layers. For example alternate layers may
comprise plies having fibres arranged substantially vertically then horizontally.
This is believed to provide a greater structural strength container. This method
may also allow the outermost ply or layer to be of a different material, for example
the outermost layer may comprise a material which can be readily printed upon.
And as mentioned previously the outermost layer may be water or moisture-proofed
using various techniques which are known to persons skilled in the art to which
the invention relates.
The multilayer construction of the endcaps is shown in Figure 4.
It is preferred that at least three and preferably four layers are provided in
the endcap. In this case they are shown in exploded view. The various layers 30,
31, 32 and 33 comprise a set of nested cones. These cones may be most simply produced
from circular pieces of material which have a sector removed to enable them to
be formed into a cone. It has been found experimentally that cones having an angle
of approximately 120° provide sufficient strength. Again as discussed in relation
to the sidewalls the materials of the plies of the cones 30, 31, 32 and 33 may
differ in order to provide additional material strength or utilise advantages
of certain materials such as ease of printing.
Other less preferred endcaps are shown in Figures 7, 8 and 9. Figure
7 shows a hemispherical endcap. This endcap 42 requires a different construction
technique from the conical endcap. A different technique of constructing the conical
endcap is illustrated in Figure 8 wherein the cone is constructed from sectors
of material. The sectors are adhered to one another using a suitable food-grade
adhesive such as PVA.
Figure 9 shows an alternative method of sealing one or both ends
of the container for a carbonated beverage. In this case the end is flattened and
folded or crimped over 50. This technique is used in the manufacture of tubes
of such substances as toothpaste etc. and the sealing may be enhanced by use of
adhesive or heat sealing. A tearaway or ripaway portion may be provided in the
crimped region 50 to enable users to readily obtain access to the carbonated beverage