Note: Descriptions are shown in the official language in which they were submitted.
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Description
Pre-Foiled Closures
Technical Field
[0001] The present invention relates to pre-foiled closures which are applied
over an
opening in a container.
[0002] Cartons and plastics containers for drinks and other liquids are
frequently sealed by
means of an induction heat sealed (IHS) foil that is bonded to a rim of a
mouth of the
container typically within a spout. The foil closes the mouth opening in order
to
provide a gas barrier.
[0003] By contrast to older style containers sealed with a peelable foil that
can be provided
with a tab so that the foil can be removed by a peeling action once the
overcap has
been removed to expose the foil, in the case of modern BAP pre-foiled closure
designs, it is normally necessary to initiate a tear in a bonded foil in order
to gain
access to the contents of the container. The foil may also have its border
bonded
between the rim and a portion of the spout as, for example in the applicant's
own
earlier application,
GB 2377701 (SPRECKELSEN MCGEOUGH LTD). 2003-01-22.
so that there is no access to the border of the foil for a peeling style of
opening.
[0004] An example of an older style closure employing a peelable foil is
described in
EP 1266839 A (PORTOLA PACKAGING LTD). 2002-12-18.
. In this case a pull tab is provided for assisting the removal of the foil
membrane.
Peelable IHS foils are thicker, may have more layers, and are heavier and
therefore
more expensive than tearable IHS foils.
Background Art
[0005] It has been suggested in
GB 2350105 A (SPRECKELSEN MCGEOUGH LTD). 2000-11-22.
that a plate be sealed to and support the foil. The plate is mounted to the
overcap so
that it can swivel relative to the overcap during the opening process. The
plate is
provided primarily to support the foil to prevent it being ruptured by gas
pressure when
the closure is used with pressurised fluids. However, opening of the overcap
also
initiates a tear in the foil membrane and breaks the seal.
[0006] In
GB 2108464 (CONTAINER CORPORATION). 1983-05-18.
there is described in relation to figures 6 to 8, a container defining an
opening, a foil
membrane closing the opening and having a border adapted to be induction heat
sealed
to a rim of the container, and an overcap having a formation terminating in an
edge
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2
bonded to the foil to define a removable portion of the foil. The formation is
a
cylindrical inner rim of a hinged lid, which is closed so that it is aligned
with and
directly supported by the rim of the container. This results in a strong seal
that is
difficult to break and the foil may remain bonded to either rim once the lid
is lifted.
The container, foil and overcap are assembled in a single operation, which
results in
assembly problems.
[0007] In the technical field of carton fitments as opposed to pre-foiled
closures which are
applied over an opening in a container to which this invention relates,
WO WO 93/13998 A (CAP SNAP CO.). 1993-07-22.
describes a closure comprising a spout defining an opening and a foil membrane
closing the opening , the closure having an openable section with a foil
retaining
formation terminating in an edge bonded to the foil to define a removable
portion of
the foil membrane, the foil membrane also being bonded to a non-openable
section of
the closure before application to a container. This closure is described by
Cap Snap as
an optional embodiment of Figure 5 in which the foil retaining formation is a
bottom
edge of a plug skirt that must be lifted up through a spout to open the
closure. Cap
Snap also teaches the use of a foil disk of greater diameter than a flange of
the fitment
that defines the spout. Only one side of the Cap Snap foil is used in the
bonding
operations. The reader is not taught how to create the weld to the foil
without welding
the skirt to the adjacent spout or how the closure can be opened. Considerable
problems would also be presented during handling of this closure by the
presence of an
unsupported and unprotected foil border beyond the flange. The closure would
also
leave the edge and other side of the foil exposed to the contents of the
container.
[0008] The larger the mouth of the container, the more difficult it is to
initiate a tear in the
foil membrane. These issues have been discussed in
GB 2404916 (SPRECKELSEN MCGEOUGH LTD). 2005-02-16.
which teaches design improvements for the mounting of a supporting leg of a
pull ring
in order to reduce the pulling force required to initiate the tear.
Disclosure of Invention
Technical Problem
[0009] The present invention addresses the technical problems that arise with
pre-foiled
closures in the opening of the foil without the littering problem of removable
pull rings
and foil and without the need for undue force, skill, knowledge or dexterity
on the part
of the user.
Technical Solution
[0010] The closure of the present invention is characterised in that the
closure has means
for engaging it over an open end of a container; in that the foil membrane is
held inside
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the closure in order to provide a border adapted to be induction heat sealed
to the
container; and in that the openable section is pivotable relative to the non-
openable
section of the closure.
[0011] The same principle can be employed with a small plastics closure in
which the
openable section is the whole of an overcap or a large can or container end in
which
the openable section is a section of an overcap that is pivotable relative to
the
remainder.
[0012] Preferably the foil membrane is bonded to a land on the non-openable
section close
to an edge of the opening in order to create a region of foil which is
stretched between
the land and an adjacent part of the foil retaining formation during the
opening process
to create an initial tear in that stretched region. Preferably the stretched
region is
opposite a hinge about which the openable section pivots open. In order to
create that
tear, it may be desirable to provide at least one foil tearing tooth between
an edge of
the opening and the land.
[0013] The edge of the formation may be continuously or intermittently welded
to the foil.
The formation is preferably a depending wall having an edge with a radius of
less than
.3 mm, preferably. .1 mm.
Advantageous Effects
[0014] As can be seen from the prior art discussed above, the idea of opening
a lid and
removing the foil at the same time is a desirable idea. However, its
implementation has
not proved straightforward as prior art proposals have proved to be unopenable
in
practice.
[0015] In use, removal of the openable section brings with it the removable
portion of the
foil. This eliminates littering issues associated with removable ring pulls.
[0016] The closure in accordance with the invention can be moulded very simply
as there
are no complex ring pull structures requiring the use of separate retractable
metal cores
which increase the cycle time of the mould.
[0017] The energy needed to weld the edge to the foil is modest because the
edge is so
fine. This is in contrast to the energy absorbed to weld a plate to the foil
as in
GB 235015 A (SPRECKELSEN MCGEOUGH LTD). 2000-11-22.
[0018] In an embodiment of the closure in which the overcap is clipped in
position and has
a peak by means of which the user can lift the overcap, the formation
preferably has a
shape which converges to a tip aligned with the peak.
Brief Description of the Drawings
[0019] In order that the invention may be well understood, five embodiments
thereof will
now be described, by way of example only, with reference the accompanying dia-
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grammatic drawings, in which:
[0020] Figure 1 is a perspective view of a spout as moulded for a closure in
accordance
with a first embodiment of the invention;
[0021] Figure 2 is a view from below of the spout of Figure 1;
[0022] Figure 3 is a section on line 3-3 in Figure 2 showing the closure with
a foil
membrane applied;
[0023] Figure 4 is a perspective view of a variation of the first embodiment
of the closure
shown secured to a can and in an open condition;
[0024] Figure 5 is a perspective view of the spout and overcap in an open
condition
showing two alternative designs for the edge of the formation in accordance
with a
second embodiment of the invention;
[0025] Figure 6 shows a plan view of the overcap and spout of Figure 5;
[0026] Figure 7 shows a section on line 7-7 of Figure 6
[0027] Figure 8 shows a plan view of the second embodiment of the closure
after it has
been assembled into a closed, foiled condition;
[0028] Figure 9 shows a section on line 9-9 of Figure 8;
[0029] Figure 10 shows a plan view of an overcap and spout in accordance with
a third
embodiment of the invention;
[0030] Figure l0a and lOb shows plan views as in Figure 10 showing variations
of the
profile for the shape of the foil retainer;
[0031] Figure 11 shows a perspective view of a closure for a can end in
accordance with
the fourth embodiment of the invention;
[0032] Figure 12 shows a section through an edge of the overcap of Figure 11;
[0033] Figure 13 shows a fifth embodiment of a closure for a can end; and
[0034] Figure 14 shows a section through an edge of the overcap of Figure 12.
[0035] The present invention can be implemented as a one- piece spout overcap
for use
over an open mouth of a container as shown in Figures 1 to 4 and 11-14 or as a
spout
and overcap combination as shown in Figures 5-10.
First Embodiment
[0036] A closure 2 for an open end of a container is made up of a spout
overcap 4 to which
a foil membrane 20 is induction heat sealed prior to the presentation of the
closure to
an open mouth of a container.
[0037] The foil membrane 20 is a double sided foil, which is a thin aluminium
foil coated
on one side with a plastics material compatible with the material from which
the spout
overcap is moulded and on the other side with a plastics material compatible
with the
material of the container. The membrane 20 may also be or contain a plastics
barrier
membrane. For example the membrane may be a laminate that contains a plastics
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barrier layer.
[0038] The spout 4 as shown in Figure 1 can be moulded in one piece from
relatively rigid
plastics materials such as HDPE or PP. LDPE would not be suitable as it would
be too
flexible. The spout 4 consists of a non-openable section in the form of an
overcap 6
with a skirt 8. An opening 10 is defined in the non-openable section and has
an edge 12
shaped to provide a convenient pouring opening. An openable section 18 is
moulded in
a vertical position as shown in Figure 1 and merges with the overcap section
at a hinge
22 formed by a thinner plastics web between a root of the openable section and
the
non-openable section. By moulding the spout in this configuration, it can be
made ef-
ficiently using a three-part mould which has two laterally separable parts to
create the
upper side of the overcap. These upper parts define between their facing
surfaces, a
cavity for creating the openable section 18. The openable section 18 carries a
foil
retaining edge formation 24 that is shaped to fit inside the opening 10. A
flange 26 at
the remote end of the openable section is angled relative to the remainder of
the section
to enable it to be gripped and lifted. This flange 26 sits outside the skirt 8
when the
openable section has been pivoted down into the same plane as the rest of the
overcap.
[0039] Figure 2 shows the underside of the overcap after the openable section
18 has been
closed down. On this surface of the overcap, a peripheral broad land 28 is
formed
around the inside edge to retain the foil membrane 20 inside the spout. A land
30 is
also provided around the periphery of the opening 10. This land 30 must be
close to an
edge of the opening 10 at least opposite the hinge 22.
[0040] As moulded, these lands are not perfectly flat but have a raised ridge
32 along one
edge. When the induction heat sealing foil membrane 20 is applied over the
surface of
the lands 28, 30, it comes into contact with the ridge 32 and it is this which
melts first
and welds to the plastics coating of the foi120. In this way, less energy is
consumed as
a world can be created simply by supplying sufficient energy to melt the
bridge and
then allowing the melted plastic to flow across the land. This also ensures
that the rest
of the moulding is not damage during the pre-foiling.
[0041] A series of foil tearing teeth 19 are formed around the edge 12 of the
opening 10.
The teeth do not need to reform all around the opening but it may be desirable
to have
at least one foil tearing tooth in the region opposite the hinge and between a
portion of
the land 30 close to the edge of the opening in that region as this is where
an initial tear
in the foil membrane will be made as the openable section is pivoted open.
[0042] In the variation of Figure 4 designed for use with a PET container
having the shape
of a standard 350m1 can. The openable section 18' extends across the entire
width of
the spout overcap 4 and has a hinge 22 at the edge of the overcap by means of
which it
is pivoted open. The openable section 18' has a liftable tab 33 moulded into a
recess in
order to facilitate the pivoting of the openable section relative to the non-
openable
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overcap section 6. As shown in the drawing, the foil retainer 24 surrounds an
opening
25 directly above the opening 10 so that the foi120 can be seen. This opening
25 can
be covered in use by a plug. In this variation the opening 10 in the overcap 6
is shown
as tear drop shaped converging to a point towards the centre of the can mouth
opposite
the hinge 22.
Assembly and Use of the First Embodiment
[0043] Spout overcap components 4 are moulded as shown in Figure 1 and removed
from
their moulds. The openable section 18 of each component is then folded down so
that
the thin foil retaining formation wall 24 snap fits into the opening 10. A
foil disc 20 is
then placed inside each overcap to cover the entire lower surface. An anvil
holds the
disc in contact with the lands 28, 30 of the surface while the assembly is in
an
induction heat sealing chamber and subjected to a magnetic field which create
sufficient heat in the aluminium foil to weld foil membrane to the lands 28
and 30 to
create a pre-foiled closure. The edge of foi120 is inside the skirt 8 and is
therefore
protected from damage during transit of the pre-foiled closures.
[0044] As with earlier BAP closures, the closures 2 can be sterilised in the
closed, foiled
condition and supplied to a factory where they will be fitted to containers.
[0045] The pre-foiled closure exposes a border of foil opposite the land 28
that can be
bonded to a rim of a container. Because this border of foi120 will be welded
on both
sides, it will be extremely difficult to separate this border from the
container without
considerable force. This weld also ensures that an exposed aluminium edge
within the
foi120 is kept securely away from the contents of the container. There should
be no
part of the container which bonds to the foil opposite the foil retainer 24
and therefore
this bond will be preferentially weaker than the bond at the rim of the
container.
[0046] When the user wishes to open the closure 2, the openable section 18 is
gripped by
the flange 26 and pivoted about the hinge 22. This causes the foil membrane 20
in the
region between the land 30 and an adjacent part of the foil retaining
formation 24
opposite the hinge (in this version adjacent the outer edge of the overcap) to
stretch
and come into contact with the foil tearing tooth 19 which will initiate the
tear if the
stretching does not. In order to design closures that require minimal force to
open
them, it is desirable to have only a relatively narrow bridge of foil in this
stretched
region between the foil retainer and a part of the foil which is bonded to the
non-
openable section. In order to achieve an opening pressure in at least this
stretched
region of the foil, it is desirable that the lifting force be applied to a
relatively small
area and this can be achieved by making the opening pointed and using a
pivoting
action to lift the foil retainer.
[0047] In the variation shown in Figure 4, the user grasps the pull tab 33 and
lifts it. This
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will create a significant opening pressure on the foil in a stretched region
between the
foil retainer 24 at the point of the tear drop shaped opening 10 in the middle
of the
container opposite the hinge 22. This region is limited by the closely
adjacent land 30
and may contain cutting teeth 19 over which the foil will be stretched to
puncture it.
Once the foil is torn, the openable section 18' can pivot about the hinge 22.
This will
also stretch the remainder of the foi120 in the region between the non-
openable section
and the land 30 close to the edge of the opening so that the tear will
propagate around
the opening resulting in a portion of the foi120 enclosed by the wall 24 being
lifted out
of the opening 10 with the pivoting openable section 18'. This ensures that
there is no
littering.
Second Embodiment
[0048] The spout and overcap embodiments will now be described with reference
to
Figures 5 to 10.
[0049] A closure 2 for fitting to a container (not shown) consists of a spout
40 connected to
a flip-top overcap 60 by a hinge 80. The spout 40 constitutes the non-openable
section
of the closure 2 and the overcap 60 the openable section. The spout 40 has a
cylindrical
wall portion 120 defining an opening 10 and a base 140. The cylindrical wall
portion
120 terminates in a pour lip 160. A sealing rib 180 is formed around an inner
surface of
the side wall 120 in order to seal against a valve in the overcap 60. A series
of foil
tearing teeth 19 are formed around the opening 10.
[0050] A foil membrane 20 is sealed across the opening 10 in the spout 40. A
border 220
of the foil membrane 20 is welded by induction heat sealing to the base 140 of
the
spout.
[0051] The structure of the spout 40 is otherwise as described in the
applicant's own earlier
application
GB 2377701 A (SPRECKELSEN MCGEOUGH LTD). 2003-01-22.
and BAP
closures manufactured in accordance with designs based on that technology,
except for the significant omission of a removable portion that is typically
moulded
across the opening 10 in the spout. Such a removable portion with its
associated ring
pull adds considerably to the cost and expense of the spout mould or spout
portion of a
hinged mould. The remaining details of the spout construction will not
therefore be
described further as they will be familiar to the skilled reader.
[0052] The overcap 60 is also substantially as described in that earlier
specification. The
overcap has a top wall 300, a side wall 320 and a peak 34 opposite the hinge
80. A
cylindrical valve 36 depends from the inside of the top wa11300 and is
positioned so
that its outer surface will engage with and seal against the sealing rib 180
inside the
side wall 120 of the spout 40. The overcap of the present invention however
differs in
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that there is an additional foil retaining formation, in this case a
cylindrical wall 400
that acts as a foil retainer. The foil retainer 400 depends from the top wall
300 of the
overcap 60 inside the valve 36. The foil retainer 400 terminates in an edge 42
that is
formed with a fine radius of .3 mm or less preferably .1 mm. The thickness of
the wall
40 tapers towards the edge 42. The height of the foil retainer 400 is such
that the edge
42 will just touch an upper surface of the foil membrane 20 when the overcap
60 is
closed over the spout 4. When the edge 42 is in contact with the foi120, it
will define
and enclose a circular portion of the foil membrane 20.
[0053] The edge 42 may be continuous as shown in the major portion of the edge
42 in
Figure 1. The edge 42 may also be crenellated as illustrated at 44. The edge
is therefore
discontinuous with short sections 46 separated by cut-outs 48. Only the
sections 46 of
the edge will weld to the foil membrane 20. It will be appreciated that the
shapes of the
cut-outs 48 are to be designed to facilitate moulding and tearing.
[0054] The foil membrane may be weakened in the region of the edge 42 to
facilitate
tearing. This weakening can be created by a laser process. It is preferable to
avoid this
step but it may be necessary for thicker foils or where the edge 42 cannot be
moulded
sufficiently fine.
[0055] An arrowhead 50 is moulded as a depression in a flat top surface of the
top wall 300
in order to point to a centre of the peak 34. This arrowhead directs the
consumer to the
peak in order to indicate the point at which the closure should be opened.
Forming the
arrowhead as a depression facilitates use of the closure by blind or partially
sighted
consumers.
[0056] A breakable tab (not shown) may be formed between an edge of the
overcap and the
spout to facilitate visual tamper evidence. Such a breakable tab must be
removed
before the overcap can be lifted. Other standard forms of tamper evidence such
as a
band or strip around the overcap may be adapted for use with this closure.
Third Embodiment
[0057] Figure 10 shows an alternative embodiment of the foil retainer 400 but
is otherwise
identical to the previously described embodiment. As shown in Figure 10, the
formation 400 is not a cylindrical wall but is shaped to converge to a
narrower tip 52
aligned with the centre of the peak 34.
[0058] Other variations for the shape of the formation are shown in Figures
l0a and lOb. In
these designs the formation 400 has a shape which defines tips 52' spaced to
either
side of the peak 34. . These designs have been found to be more effective in
tearing out
the enclosed portion of foil with minimal effort.
Method of Assembly and Use of the Overcap and Spout Embodiments
[0059] It will be appreciated that the spout and overcap embodiments described
can be
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moulded readily in one piece with a mould that forms the spout and overcap
together
in an open condition as shown in Figure 5. The closure 2 is assembled by
pivoting the
overcap 60 about the hinge 80 so that the valve 36 is engaged inside the spout
40. In
this closed condition as shown in Figure 9, a foil membrane 20 is placed in
the base
140 of the spout and induction heat sealed to the spout. The induction heat
sealing
process will weld the foil to the areas of plastics material that it is
touching when the
placing pressure is applied. Therefore, the border 220 of the foil will weld
to a
horizontal surface of the base. The edge 42 or those spaced portions of it 46
which
touch the foi120 will also weld to it. Limiting the area of contact between
the foil and
the plastics of the spout 40 and edge 42 reduces the amount of energy used to
weld the
foil and reduces the effort to tear it later.
[0060] As with earlier BAP closures, the closures 2 can be sterilised in the
closed, foiled
condition and supplied to a factory where they will be fitted to containers.
[0061] When a container that has been closed with a closure as described is
received by the
consumer, it can be opened by the application of a lifting and pivoting force
applied to
the peak 34 of the overcap at the position indicated by the arrow 50. On first
opening
the closure, there will be a degree of resistance as the foi120 is lifted and
stretched by
the formation 400. This lifting force will eventually tear the foil adjacent
the edge 42.
As the foil is ruptured, there will be an audible pop. This provides consumer
re-
assurance that the closure has not been tampered with.
[0062] When the overcap 60 is pivoted fully open, the space within the foil
retainer 400
will normally be covered by the enclosed portion of the foil which has been
removed
during the opening process. The foil may also be torn by the teeth 19 at the
edge of the
opening 10.
[0063] In the embodiment of Figure 10, the lifting force applied by the user
to the peak 34,
initially creates a tear at the tip 52 at which the force is concentrated. The
tear will then
propagate in both directions around the edge 42 resulting in a droplet shaped
enclosed
portion of foil being removed with the overcap. A similar effect will be
produced using
the profiles of Figures l0a and lOb. Shaping the edge 42 in one of these ways
is par-
ticularly desirable in applications with larger closures and thicker foils.
[0064] In most cases, it will be possible to dispense the contents of the
container through
the opening created by removal only of the portion of the foi120 that is
enclosed by the
edge 42. However, the remaining region of the foil (if any) across the opening
10 may
be pushed into the container to clear the entire opening 10.
[0065] Since the removed portions of the foi120 are retained in the closure,
littering issues
are eliminated.
[0066] It will be appreciated that the exact tearing propagation will depend
on the force
applied during the opening process and the utility of the closure as described
is not
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dependent on any particular tearing pattern.
[0067] The closure can be resealed by the consumer as with the existing BAP
closures.
Different shapes and designs of the overcap can readily be implemented for
brand dif-
ferentiation purposes. The construction of the present invention therefore
retains all the
consumer attributes of the earlier closures but allows a simpler mould and a
lighter
weight closure. The invention therefore makes a closure that is suitable for
applications
which are of greater price sensitivity.
Can End Embodiments
[0068] Figures 11 to 14 relate to an implementation of the invention in which
a single piece
moulded closure 600 (as opposed to a two piece moulded or hinged unit) is
designed to
replace the whole of an end of a cylindrical can 61, for example a drinks can
or bottle
made of thermoformed plastics material. The can is essentially cup shaped and
has an
opening which is closed by the closure 600.
[0069] The closure 600 comprises an overcap 62 having a flat top 64 and a
depending skirt
66, and a foil membrane disc 68 held inside the overcap by means of a foil
retaining
formation 70 in the form of an annular ridge or land that is formed on an
inner surface
of the top 64. The foil retainer 70 terminates in an edge 72 that is bonded to
the foi168.
[0070] An edge of the skirt 66 has a bead 74 formed around its internal
surface in order to
provide means by which the overcap can be engaged over the can end to hold it
in
position during assembly. The closure 600 is sealed to the can end by
induction heat
sealing of a border of the foi168 to a rim of the can.
[0071] The overcap 62 also has a section 800 that is adapted to be torn from a
remainder of
the overcap to create a drinking or pouring opening. The section 80 carries an
arcuate
section 82 of the foil retaining formation 70. The section 80 is separated
from the
remainder of the overcap by tear lines 84 along each side. These tear lines 84
are
thinner plastics webs. A hinge 86 is formed in the overcap at a back of the
removable
section 800 nearest the centre of the top 64. A peak 88 can be moulded at the
front
edge of the section 80 to facilitate lifting of the section. A tab 90 is
formed so that it
projects outwardly from the remainder of the skirt 66 so it can be grasped to
initiate the
tearing of off of the section 800 and subsequent opening by pivoting the
section 800
about the hinge 86. When the section 800 is opened in this way, the foil will
be torn as
it is lifted by the section 82 of the foil retaining formation 70.
[0072] The tab 90 can be clipped right over out of the way of the user's mouth
by clipping
it over the edge of the skirt 66 opposite the opening. After opening, the can
can be
closed by bringing the section 80 back over the opening.
[0073] An alternative style of can end closure is illustrated in Figures 13
and 14. Like
reference numerals are used for similar parts. In this embodiment the overcap
62 does
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not have a continuous upper surface but exposes parts of the foil membrane 68.
A
portion 94 of the upper surface of the overcap 62 is moulded in such a manner
that it
can be removed by gripping on a pull tab 96. In this embodiment the foil
retainer is a
wall formation 98 underneath the portion 94 indicated by dotted lines. This
formation
98 does not need to be a closed circle as shown in previous embodiments. There
may
also be more than one foil retainer edge. This type of can end can be adapted
for
various types of spout construction.
[0074] It will be appreciated that given the concept of a foil retainer with
an edge welded
to the foil membrane on a part of an overcap that is removed during the
opening
process, the skilled man will be able to design various patterns and
configurations for
such edges that facilitate tearing and lifting of the required parts of the
foil needed to
leave a convenient drinking opening. The removed parts of the foil held by the
foil
retainer edges can also be designed to have aesthetic shapes.
Variations
[0075] The closure as illustrated in Figures 5 to 10 is intended for use with
a 33mm
bottleneck but it will be appreciated that it can be used for wide mouthed
bottles and
smaller drinks bottles as well as adapted for wide mouthed jars, cartons, cans
and
thermoformed containers of all manner of diameters.
[0076] Additional tamper evidence can be provided by a removable or breakable
tab
adjacent the peak 341ocking the overcap to the adjacent wall of the base. In
the can
end embodiment, a similar breakable tab or other tamper evidence structure may
be
provided. The can end embodiments can also be used on a variety of can
diameters.
[0077] Moulding the overcap 6, 60 or 62 out of a see through or clear or
clarified plastics
material also offers additional visual tamper evidence.
[0078] It is therefore possible to provide feedback by visual, audible and
touch
mechanisms to reassure consumers that the products supplied with the closure
has not
been previously opened or tampered with.
