Note: Descriptions are shown in the official language in which they were submitted.
CA 02305578 2000-03-31
WO 99/16677 PCT/GB98102945
-1-
The present invention relates to a can end having a
stay-on type lift tab, and a seal for a can end which provides
a safety feature for the lift tab mechanism.
Many beverages are packaged in stay-on type lift tab
cans of various sizes. Such beverages include soft drinks,
beers, wines and health drinks. An advantage of this form of
packaging is that the product may be maintained in an enclosed
light-free environment which, if desired, may be pressurised.
Once sealed in the can, the possibility of the contents becoming
contaminated within the can, either by chance or deliberate
intent is very small.
However, current designs of can ends having a lift tab
have a number of disadvantages. Current lift tabs have the
disadvantage that it is possible that, at the point of opening
and consumption, the product may become contaminated. When
current can ends are opened, there is an area of the end which
becomes a flap. As a result, an area of the end which was
previously external to the contents of the can comes into contact
with the contents. Thus any contamination of the area just
mentioned will be transferred to the contents.
Further, there is generally a space between the end of
the lift tab and the can end which may include an indentation to
prevent skidding of the tab when lifted. It is this space which
represents a more serious potential source of contamination.
When the contents of the can are poured out, any contamination
of this space is rinsed out together with the contents of the
can. Contamination of this nature may arise by accident or
deliberate design.
CA 02305578 2000-03-31
WO 99/16677 PCT/GB98/02945
-2-
For example, the presence of a small amount of aversant
in this space could be sufficient to impair the flavour of the
dispensed product. The effect would be particularly noticeable
if the contents of the can were drunk direct by mouth or if only
a small amount of product were dispensed into a drinking vessel
prior to consumption.
In addition, a further disadvantage of current can ends
having lift tabs is that they are difficult to lift, particularly
for people with arthritic finger joints or fragile finger nails.
It is therefore an object of the present invention to
provide a can end which substantially reduces the risk of
contamination and which enables the user to open the lift tab
with reduced risk of damage to finger nails and reduced need for
flexible finger movement.
According to a first aspect of the present invention,
there is provided a can end including:
(a) a disc-shaped panel having a peripheral edge to be engaged
with a rim of a can body, the panel having a frangible
area; and
(b) a stay-on type lift tab provided on the panel and having a
pull-up end and an opposed end arranged to bear on the
frangible area; and
(c) a seal member attached to the panel, the attachment being
between the frangible area and the peripheral edge such
that the seal member covers the frangible area and the lift
tab.
Typically, the lift tab has a connecting portion which
is rotatably connected about an axis perpendicular to the panel.
It is envisaged that in a first embodiment of the
present invention the panel further includes a recess arranged
to house the lift tab. Advantageously, in this embodiment the
seal member is arranged to be flush with the surface of the
panel.
Typically the seal member is attached to the panel
using an adhesive which is suitable for a food/beverage type
application, such as for example, a latex based adhesive.
Advantageously, the seal member acts as a tamper-proof or tamper-
CA 02305578 2000-03-31
WO 99/16677 PCT/GB98/02945
-3-
indicating seal and further includes a flap portion which is free
and not attached to the panel. In one embodiment, such a flap
portion may be generally substantially opposite the can end lift
tab.
However, it is also envisaged that the seal member may
be attached to the panel by adhesive which is arranged
substantially along the outer periphery of the seal member, the
seal member having a line of weakness parallel to the outer
periphery and defining a frangible area of the seal member. In
this embodiment of the invention, as the pull up end is pulled
up, the seal member is broken along the line of weakness and the
frangible area of the seal member is removed from the can end,
leaving the outer periphery of the seal member attached to the
panel.
The seal member may be advantageously made from the
same material as the can, so as to ease recycling. For example
when the can is made from steel, the seal member is made of
steel, and when the can is made from aluminium, the seal member
is made of aluminium. Alternatively, the seal member may be made
from a laminate or plastics film such as polypropylene.
The seal member is preferably continuous and
substantially liquid-impermeable to minimise the possibility of
contamination of the contents of the can having a can end
according to the invention.
Desirably, the seal member is further attached to the
lift tab, thus allowing the pull-up end of the lift tab to be
lifted when the tab portion is pulled up. Preferably, the seal
member is attached to the pull up end with an adhesive such as
an epoxy resin, or by welding. Alternatively, the seal member
may be attached to the pull up end by means of a loop threaded
through a hole in the pull up end. In order to break open the
seal member, the lift tab may be pulled upwards; this same action
raises the pull-up end of the lift tab and opens the can, or at
least begins the opening process, by causing the opposed end to
bear on the frangible area and thereby initiating the fracturing
process (and form a corresponding opening in the panel). In the
latter instance because the lift tab becomes readily accessible,
CA 02305578 2000-03-31
WO 99/16677 PCTIGB98/02945
-4-
the remainder of the opening process can be accomplished by
lifting the lift tab direct.
Because after opening, the seal member may remain
attached to the ring pull, it cannot readily be discarded
separately after use. It is therefore unlikely to be a cause of
litter nuisance.
It is preferred that the seal member may be such that
it can be removed substantially in whole from the panel when the
pull-up end is pulled upwards.
When the contents of the can are to be drunk direct by
mouth, it is preferred that substantially all the area which
comes into contact with the mouth is initially covered by the
seal member.
The seal member may be simple and small, and may be
fitted to existing types of cans without the need for major
modification of the lift tab mechanism. Similarly, the present
facility for cans to be stacked one upon the other need not be
compromised by the provision of a can end in accordance with the
invention. The seal member may provide, in an inexpensive
manner, improvements in both the security and the method of
opening of the can.
According to a second aspect of the present invention,
there is provided a can including a can body having a closed end
and an open end spaced therefrom, a peripheral wall extending
between the closed end and the open end, there being a peripheral
rim at the open end, and a can end as herein before described
engaged with the rim.
Features of the invention may be more clearly
understood by reference to the accompanying illustrative
drawings, which axe given by way of example only, in which:
Figure 2 is a plan view of a conventional can end;
Figure 2 is a similar plan view showing a can end
according to the invention;
Figure 3 is a plan view showing a can end according to
a second aspect of the invention;
CA 02305578 2000-03-31
WO 99/16677 PCT/GB98/02945
-5-
Figure 4 is a sectional view through the can end of
Figure 3 along the line x-x;
Figure 5 is a plan view of a can end according to a
third aspect of the present invention;
Figure 6 is a sectional view through the can end of
Figure 5 along the line y-y; and
Figure 7 is a sectional view through the can end of
Figure 5 along the line z-z.
Referring initially to Figure 1, this illustrates a
conventional can end known in the art, generally indicated by the
numeral 1. The can end 1 comprises a disc-shaped panel 2 and a
stay-on type lift tab 3. The lift tab 3 is attached to panel 2
at pivot point 4.
The panel 2 has a generally 'C' shaped score line 5 in
its upper surface. The score line 5 can be formed by making a
shallow score in the upper surface of the panel 2. The score
line 5 as illustrated starts from a point adjacent to the centre
of the panel 2 (near pivot point 4), passes a point adjacent the
outer periphery of the panel 2, and terminates at a further point
adjacent the centre of panel 2. In general, the score line 5 as
illustrated consists of two parallel scores 51 and 52. The outer
score 51 is the main score to be torn by pulling at the lift tab
3, and the inner score 52 is an auxiliary score'which facilitates
the tearing of outer score 51.
The can is opened by lifting the lift tab 3 at point
6. Initially, this causes the other end of the lift tab 3 at
point 7 to press down on the surface of the can end 1.
The positioning of the lift tab 3 is such as to result
in the fracture of the can end 1 at score line 5. Further
downwards pressure results in scored portion 8 being pushed down
into the can thus creating an opening defined by what was the
score line 5. Access to the contents of the can may be gained
through this opening.
Referring now to Figure 2, this shows how a can end
such as that illustrated in Figure 1 can be modified so as to
embody the present invention. A plastic seal 21 covers the
entire lift tab mechanism (which may be generally as described
CA 02305578 2000-03-31
WO 99!16677 PCT/GB98/02945
- 6-
above with reference to Figure 1). The seal 21 is bonded to the
can end along bond line 22, and is also attached to the lift tab
mechanism 25 at point 24.
The pull flap 23 is not bonded to the panel 2. Line
26 is parallel to the bond line 22. In use, the pull flap 23 is
lifted and the seal 21 tears along the line 26, exposing an
uncontaminated portion around the score lines of the lift tab
arrangement. As the pull flap 23 is pulled back and up, the
action causes the lift tab to be raised, causing downward
pressure on the scored portion, which results in the fracturing
of the can end along the scored line.
Referring to Figure 3, this shows how a can end such
as that illustrated in Figure 1 can be modified so as to embody
a second aspect of the present invention. An aluminium seal 20
covers the entire lift tab mechanism (which may be generally as
described above With reference to Figure 1) . The seal 20 is
bonded to the can end along bond line 22, and is also attached
to the lift tab mechanism 25 at point 24.
The pull flap 23 is not bonded to panel 2. In use, the
pull flap 23 is lifted and seal 20 is removed from the can end
2. As the pull flap 23 is pulled back and up, the action causes
the lift tab to be raised, causing downward pressure on the
scored portion, which results in the puncturing of the can and
along the scored line 5. In this embodiment, the entire seal 20
is removed from the panel 2.
Reference will now be made to Figure 4, in which like
reference numerals have been used to identify like parts
corresponding to those in Figures 1, 2 and 3. A loop 30 is
attached to seal 21 (or with reference to Figure 3, seal 20) as
well as to lift tab 3 at point 24. When the seal 21 is pulled
backwards and upwards, loop 30 is also pulled backwards and
upwards. The resultant action causes lift tab 3 to be lifted,
which in turn initiates the fracturing of can end 1 at score line
5.
Referring to Figures 5, 6 and 7, these show how a can
end such as that illustrated in Figure 1 can be further modified
to embody a third aspect of the present invention. An indent 105
CA 02305578 2000-03-31
- _ WO 99/16677 PCT/GB98/02945
is formed in panel 102 to define an indented or recessed portion
106. A lift tab, as illustrated in Figure 1, is provided on
indented or recessed portion 106.
A steel seal 121 covers the entire lift tab mechanism,
and lies flush with the non-indented portion of panel 102. The
seal 121 is bonded to the can end along bond line 122, and is
also bonded to the lift tab mechanism 125 at point 124.
Seal 121 is welded to lift tab mechanism 103 at point
124. When the seal 121 is pulled backwards and upwards, the
resultant action causes the lift tab 125 to be lifted which in
turn initiates fracturing of can end at the score line.
