Note: Descriptions are shown in the official language in which they were submitted.
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A CARTON HAVING FIRST AND SECOND PATTERNS OF WEAKNESS
Technical Field of the Invention
The present invention relates to a carton and more
particularly to a closure system of a carton. In one
preferred embodiment, the carton is for a solid
confectionary block such as a chocolate block.
Background to the Invention
Although chocolate blocks are traditionally packaged
within an outer wrapping of paper or foil, alternatively
they may be packaged within an outer carton composed of a
thin board. Previous carton designs proposed for this
purpose have a closure in the form of an end flap which,
in the unopened carton, is retained by gluing to an
adjacent wall of the carton. These existing closure
arrangements are not particularly easy to open especially
by older persons or less dextrous persons and, likewise,
the flap may not always be easy to close after opening.
The difficulties are such that some consumers simply tear
open the carton and which is easy to do as the carton is
quite thin, but once torn open in this way the carton
cannot be properly reclosed and also, having been torn, is
quite unsightly.
The present invention seeks to provide a carton of the
general type discussed above with an improved opening and
re-closure facility.
Summary of the Invention
According to the present invention there is provided a
carton erected from a blank, the carton having a closure
flap held in a closed condition prior to initial opening
of the carton by a connection between a face of the
closure flap and an opposing face of an adjacent wall of
the carton, wherein the connection is to a part of the
adjacent wall which is removable from the remainder of
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that wall along one or more first patterns of weakness,
the connection being in a predetermined zone of the
removable part defined by one or more second patterns of
weakness so that when the part is removed from the
remainder of the wall, the predetermined zone can be
separated the remainder of the removable part along the
second pattern(s) of weakness to remain attached to the
closure flap.
In a carton in accordance with this aspect of the
invention, separation of the removable part from the wall
along the first pattern(s) of weakness may also cause the
connected zone to separate from the part along its
associated second pattern(s) of weakness. To ease the
separation of the connected zone, it may be defined by a
pattern of weakness of a continuously curved profile such
as elliptical or circular. In alternative configurations,
it may not be a continuously curved profile.
The connected zone may provide the only zone of connection
between the closure flap and the adjacent wall of the
carton prior to initial opening.
When the part of the adjacent wall is removed as defined
above to permit release of the closure flap, a recess of
corresponding shape is formed in the wall and in one
embodiment of the invention, the closure flap is so
configured that after its release it can be reclosed by
tucking a free edge of the flap behind an edge of the
recess. The recess may open onto an outer edge of the
wall, and prior to initial opening of the carton the flap
may be located inside of that outer edge, whereas to
reclose the carton after initial opening the configuration
of the flap may be such that a free edge portion of the
flap is able to engage behind an edge of the recess
inwardly of the outer edge of the wall. The closure flap
may be connected along one edge with a panel forming a
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further wall of the carton, the free edge portion of the
flap being distal from said one edge. To aid in retaining
the free edge of the flap, the flap may be shaped to
provide a first zone of constant width immediately
adjacent the panel, the flap progressively narrowing in a
direction away from the panel to a second zone of constant
width and narrowing progressively from the second zone of
constant width towards the free edge. The first zone of
constant width may have a width which is substantially the
same as that of the panel.
The carton may be erected from a blank and in one form,
the carton is erected by folding the blank around a
product to be packaged within a carton, a confectionary
block for example., In this form, the retention of the
flap by a glued connection prior to opening is
particularly convenient as the actions of folding a blank
around a product in a production line situation and
applying glue to predetermined parts of the blank during
the process can readily be performed by existing
commercially available machinery.
Alternatively, however, the flap could be retained in
other ways, such as by double-sided adhesive tape or by
mechanical retention such as stapled or riveted connection
or a frictional connection. Certain of these retention
methods may be more applicable in a situation where the
carton is pre-formed prior to insertion of the product.
According to a further aspect of the invention there is
provided a blank for erection into a carton, the blank
having panels foldable to form walls of the carton, and a
flap foldable for closing an access opening of a carton
whereby in the erected carton the flap is retained prior
to initial opening by connection to part of an adjacent
wall of the erected carton, the said part of the wall
being formed by a part of one of said panels which is
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removable from that panel along one or more first patterns
of weakness to permit release of the flap, wherein the
said part of the said one panel includes a zone defined by
one or more second patterns of weakness whereby when, in
the erected carton, the flap is connected to the said one
panel in that zone, release of the flap to open the carton
can be effected by removal of the said part of the panel
and separation of the said zone from the part.
The said zone may be of a continuously curved profile such
as elliptical or circular.
The said part of said one panel may be of generally
rectangular shape. In which case, at least one edge of the
said part is defined by an edge of the panel. In one
embodiment, two adjacent edges of the said part are
defined by two adjacent edges of the said one panel
forming a corner portion of the panel.
The said part may include a projecting tab to facilitate
its removal.
In one embodiment, the closure flap is connected along one
edge with a further panel which in the erected carton
forms a further wall of the carton, the flap having a free
edge region distal from said one edge, the closure flap
being shaped to provide a first zone of constant width
immediately adjacent the said further panel, the flap
progressively narrowing in a direction away from the said
further panel to a second zone of constant width and
narrowing progressively from the second zone of constant
width towards the free edge. The first zone of constant
width may have a width which is substantially the same as
that of the said further panel.
According to yet another aspect of the invention there is
provided a method of erecting a carton from a blank as
specified above, comprising placing a product to be
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packaged on a panel of the blank other than said one panel
and sequentially folding other panels around the product
to enclose the product, wherein the said flap is folded
over the product prior to folding the said one panel over
the product, and the said one panel is subsequently folded
over the product to overlie the flap, the method further
comprising connecting the said part of the said one panel
to the flap in said zone to thereby retain the flap
thereto.
Advantageously, the method comprises applying glue to
connect the said part of the said one panel to the flap,
and applying glue to other parts of the blank to connect
adjacent folded parts and maintain the carton in its
erected state.
Detailed Description of the Invention
An embodiment of the invention will now be described by
way of example only with reference to the accompanying
drawings in which:
Figure 1 is a view from the rear of the carton in
accordance with a preferred embodiment of the invention;
Figure 2 is a view from the front of the carton;
Figure 3 is a perspective view showing the rear of the
carton;
Figure 4 shows a blank of flat board from which the carton
is erected;
Figures 5 and 6 show schematically successive stages in
the opening of the carton by removal of a part of the rear
wall of the carton to release an upper closure flap; and
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Figure 7 shows schematically how the upper closure flap
can be reclosed following opening.
Figures 1 to 3 show the carton prior to opening, the
carton being erected from the blank 10 shown in Figure 4.
The blank which is formed from thin board, fibre board for
example, comprises a main panel 2 which forms the front
wall of the carton and outer side panels 4, 6 which, when
the carton is erected, overlap to form the rear wall. The
outer side panels 4, 6 are connected to the main panel 2
by narrow intermediate panels 8, 10 which form the
opposite side walls of the erected carton. A lower closure
flap 12, associated tabs 14, and a narrow intermediate
panel 16 between flap 12 and panel 2 form a lower closure.
An upper closure flap 18, associated tabs 20, and narrow
intermediate panel 22 form an upper closure.
In practice, a carton of the preferred embodiment is
designed to be erected around the product to be enclosed
by the carton. When the product is a block confectionary
product, a chocolate block for example, the product
already enclosed in an inner foil wrapping is placed on
the main panel 2 and the other panels and flaps are
sequentially folded and adhered together by glue to form
the completed carton as illustrated in Figures 1 to 3. The
general techniques for folding the flaps and applying glue
in a production line situation are well known in the
packaging industry and do not need to be further described
here. In the carton of the preferred embodiment, glue is
applied along the edge of one or other of the two outer
panels 4, 6 to form an overlapping glued seam which is
shown in Figure 2. The lower closure which is principally
formed by the lower closure flap 12 is of substantially
conventional construction. The lower closure is intended
to remain permanently closed and for this purpose the
lower closure flap 12 and intermediate panel 16 is
permanently retained in position by gluing of the flap 12
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to the inner surface of one or other of the outer panels
4, 6.
The upper closure flap 18 is an openable and re-closable
flap to provide access to the contents of the carton. Its
construction and its mode of co-operation with the rear
wall of the carton prior to opening and upon re-closure
will now be described in detail.
With reference to the blank of Figure 4, it will be seen
that the upper closure flap 18 is shaped to provide a zone
18a (shown by the stippling in Figure 4) of constant width
immediately adjacent the intermediate panel 22 which forms
the upper end wall of the erected, closed, carton. The
width of the zone 18a corresponds to that of the front
panel 2 and hence to that of both the front and rear walls
in the erected carton. Beyond the zone 18a, the flap 18
then progressively narrows to a second zone 18b (shown by
the crosshatching in Figure 4) of constant width and from
that second zone 18b of constant width, it narrows
progressively towards its free end. The function of this
second zone 18b of the flap 18 will be described later. In
the erected carton prior to opening, the flap 18 is
retained in its entirety beneath the rear wall formed by
the overlapping side panels 4, 6.
The panel 4 includes at its upper end a removable part 30
of generally rectangular shape, the part 30 being joined
to the remainder of the panel 4 by first patterns of
weakness 32 as exemplified below. Within this removable
part 30 is a removable zone 34 which, in the embodiment
illustrated, is generally of an elliptical shape but could
be of any other shape, circular for example, which
achieves the function to be described below. The removable
zone 34 is likewise defined by second pattern(s) of
weakness 36 as exemplified below.
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The first and second patterns of weakness, which may be
lines of weakness, may be formed by, for example,
perforations or scoring extending only partially through
the thickness of the board; such scoring may extend from
the inner surface of the board outwards, or the outer
surface of board inwards, or a mixture of both. The
scoring, perforations or other patterns of weakness may be
formed by laser cutting or by mechanical means, for
example.
In the erected carton prior to opening, the upper closure
flap 18 is retained by gluing only to the rear wall only
in the area defined within this small removable zone 34 of
elliptical shape. Accordingly, the flap 18 is retained, by
gluing, only to the removable part 30 of the rear wall,
with the glued connection being confined to within the
removable zone 34 of that part 30. With reference to the
detailed construction of the flap 18 shown in Figure 4,
the glued connection to the zone 34 is located in the zone
of the flap 18 between the zones 18a and 18b. In the
erection of the carton around the product as outlined
above, the flap 18 is folded over the product prior to
folding the panels 4, 6 which form the rear wall and the
glue for providing the connection to the zone 34 can be
applied either to the upper face of flap 18 after folding
or upper face of the removable part 30 prior to folding of
the panel 4.
In order to release the upper closure flap 18 to open the
package, the larger removable part 30 is removed from the
rear wall by tearing along the first patterns of weakness
32 and during removal of that larger part 30 it will also
separate from its glued connection with the upper closure
flap 18 by tearing along the second pattern of weakness 36
which separates the inner glued zone 34 from the remainder
of the removable part 30. The curved profile of that inner
zone readily promotes that action during the separation of
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the larger part 30. A small tab 38 can be seen to project
from the upper edge of the part 30 to facilitate easily
gripping that part for the purposes of removal and the tab
38 may carry instructions to the consumer to "OPEN HERE".
The upper closure configuration described provides firm
and secure retention of the upper closure flap 18 prior to
opening, but the package can easily be opened by removal
of the part 30 by tearing along the defined patterns of
weakness as indicated schematically in Figures 5 and 6.
This has the effect of releasing the upper flap 18 as the
glued connection between the flap 18 and the part 30
itself separates from the removed part by easily tearing
along the inner pattern of weakness 36. The effect of this
is twofold. Firstly, releasing of the flap 18 does not
require application of a force sufficient to break the
glued connection itself; the force applied merely needs to
be sufficient to permit tearing along the various patterns
of weakness and the design of these can readily be
configured to permit ease of tearing. Secondly, the fact
that the glued connection is itself not broken provides a
distinct aesthetic element in that no unsightly broken
glued connection will be visible when the carton is
opened. All that will be visible on the outer surface of
the closure flap 18 after opening is the small elliptical
(or other shaped) zone 34 which remains glued to the
exposed outer surface of the flap 18. That attached zone
34 could, for instance, carry a trade mark applicable to
the product in order to provide a sense of aesthetic
design integrity to that part of the closure flap 18 after
opening.
It will be understood that as the package is designed only
to be opened by removing the part 30 of the rear wall in
the manner described and which will require complete
separation of the inner zone 34 and at least substantial
separation of the overall part 30 from the rear wall, the
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state of the part 30, either absent or at least
substantially separated, will immediately provide clear
visual evidence of tamper and conversely even upon casual
inspection it should be immediately apparent that the
presence of the part 30 without any tearing should
indicate that there has in all probability been no
tampering with the package.
As the part 30 is quite "cleanly" removable from the
carton and has a relatively significant size, it can also
be used as a token redeemable for promotional activities.
For example the part 30 may be printed on its inside
surface, that is the surface not visible to the consumer
prior to opening the carton, with indicia concerning a
prize which can be obtained when the token is redeemed; it
will be understood that in this case the indicia must
appear within the area outside of the inner removable zone
34.
When the part 30 has been removed to permit release of the
upper closure flap 18, a recess of approximately
rectangular shape will be left in the upper edge part of
the rear wall and this is shown in Figure 6. It will be
seen that the recess is bounded on opposite sides by the
remaining portions of the rear wall. Although the carton
could be reclosed after opening by tucking the closure
flap 18 under those remaining portions, that is rather
cumbersome. Instead the flap 18 is designed to be reclosed
by folding the flap 18 back over the rear wall so that the
main body of the flap 18 lies on the outside of the rear
wall rather than on the inside of the rear wall as
occurred during initial erection and sealing of the
carton. In this state the flap 18 can then be retained in
its closed state by tucking the narrowed free end part of
the flap 18 beneath the lower edge 40 of the recess now
present in the rear wall (this is shown in Figure 7). This
effect is facilitated by the presence of the secondary
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zone 18b of constant width, the width of this being
slightly less than the width of the recess itself.
It will be noted that in the particular design shown in
the drawings, the main removable part 30 of the rear wall
extends to the upper edge of the panel 4 and side edge of
the panel so that the part 30 defines a comer portion of
the panel 4. Although this is preferred as its removal
merely requires tearing along two principal patterns of
weakness, one at right angles to the other and
interconnected by a radiused portion to facilitate a
smooth tearing action, nevertheless in alternative forms
the removable part could be positioned more centrally
within that panel.
The embodiment has been described by way of example only
and modifications are possible within the scope of the
invention. For example although as shown, the closure
system is associated with one of the two ends of the
carton, specifically the upper end, in other embodiments
it could be associated with one or other of the two sides
of the carton.
Although as described, the carton is erected by folding
around the product, it may alternatively be pre-formed
prior to insertion of the product(s) to be contained
therein. As an alternative to gluing the inner removable
zone 34 to the closure flap 18 it may be secured thereto
in alternative ways such as by the use of double-sided
adhesive tape or by a mechanical fastening such as a
staple, rivet or frictional connection. Certain of these
alternatives may however only be applicable for use in a
pre-formed carton.
Although the invention has been particularly described
with reference to a carton for a confectionary product
such as chocolate in block form it is to be understood
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that the closure system described herein could be used in
cartons for a variety of different products.
