U.S. patent application number 10/595820 was filed with the patent office on 2007-05-03 for fitments.
This patent application is currently assigned to BAPCO CLOSURES RESEARCH LTD.. Invention is credited to Peter Michael McGeough, Henning Von Spreckelsen.
Application Number | 20070095834 10/595820 |
Document ID | / |
Family ID | 29726587 |
Filed Date | 2007-05-03 |
United States Patent
Application |
20070095834 |
Kind Code |
A1 |
Von Spreckelsen; Henning ;
et al. |
May 3, 2007 |
Fitments
Abstract
A carton fitment (2) has a base flange (4) and a pour spout (6)
closed by a screw on overcap (8). The base flange (4) has a barrier
foil (30) coated on both sides with a plastic layer embedded in a
sacrificial receiving wall (32) surrounding the periphery of the
base flange (4).
Inventors: |
Von Spreckelsen; Henning;
(SURREY, GB) ; McGeough; Peter Michael; (SURREY,
GB) |
Correspondence
Address: |
CHRISTOPHER J. KULISH, ESQ
HOLLAND & HART LLP
P. O. BOX 8749
DENVER
CO
80201-8749
US
|
Assignee: |
BAPCO CLOSURES RESEARCH
LTD.
Surrey
GB
GU21 4SU
|
Family ID: |
29726587 |
Appl. No.: |
10/595820 |
Filed: |
June 25, 2004 |
PCT Filed: |
June 25, 2004 |
PCT NO: |
PCT/GB04/02744 |
371 Date: |
May 12, 2006 |
Current U.S.
Class: |
220/258.2 ;
220/270 |
Current CPC
Class: |
B65D 5/749 20130101 |
Class at
Publication: |
220/258.2 ;
220/270 |
International
Class: |
B65D 51/20 20060101
B65D051/20; B65D 17/34 20060101 B65D017/34 |
Foreign Application Data
Date |
Code |
Application Number |
Nov 14, 2003 |
GB |
0326619.4 |
Claims
1. A fitment comprising a base flange (4) and a hollow spout (6), a
removable part (10) within a base of the spout (6), and an overcap
(8) for resealably closing the spout (6), and a barrier foil (30)
coated on both sides with a plastics layer extending across the
base flange (4), characterised in that the foil (30) is a coated
aluminium foil that has an exposed aluminium cut edge prior to
assembly in the fitment, and that the edge of the foil (30) is
assembled to the flange (4) in such a manner that the aluminium cut
edge is prevented in use from coming into contact with contents of
a container to which the fitment is assembled with the base flange
inside the container.
2. A fitment as claimed in claim 1, characterised in that the
aluminium cut edge of the foil (30) is embedded in the base flange
(4).
3. A fitment as claimed in claim 1 or 2, characterised in that the
foil (30) is sealed to the base flange (4).
4. A fitment comprising a base flange (4) having a first surface
(54) and a hollow spout (6) projecting from a surface (56) opposite
the first surface (54), a removable part (10) within a base of the
spout (6), and an overcap (8) for resealably closing the spout,
characterised in that a barrier foil (30) coated on both sides with
a plastics layer is wrapped over the first surface of the flange
(4) such that the foil extends onto the opposite surface (56)
surrounding the spout.
5. A fitment as claimed in any one of the preceding claims, further
comprising tamper evident means.
6. A paperboard carton with a fitment (2) as claimed in any one of
the preceding claims inserted into a pre-cut hole (20) in a
composite paperboard wall (22), characterised in that a seal
between edges of the foil (30) and the wall (22) are of the same
integrity as other seams in a remainder of the carton.
7. A plastic coated or barrier coated metal container with a
fitment (2) as claimed in any one of the preceding claims inserted
into a pre-cut hole (20) in a wall of the container, characterised
in that a seal between edges of the foil (30) and the wall are of
the same integrity as other seams in a remainder of the
container.
8. A mono or multi-layer plastics container which is thermoformed,
injection moulded, or blow moulded, with a fitment (2) as claimed
in any one of the preceding claims inserted into a pre-cut hole
(20) in a wall of the container, characterised in that a seal
between edges of the foil (30) and the wall are of the same
integrity as other seams in a remainder of the container.
9. A method of manufacturing a fitment comprising the steps of
placing an aluminium foil having a plastics layer on each surface
within a receiving wall projecting from a first surface of a base
flange of a fitment that has a hollow spout extending from an
opposite surface, and welding the foil to the flange such that the
wall is sealed over an aluminium cut edge of the foil.
10. A method as claimed in claim 9, further comprising the step of
folding the receiving wall over the edge of the foil prior to the
securing step.
11. A method as claimed in claim 9 or 10, wherein the securing step
is carried out by induction heat sealing.
12. A method of manufacturing a fitment comprising the steps of
wrapping a foil having a plastics layer on each surface over a
first surface of a base flange of a fitment that has a hollow spout
extending from an opposite surface such that the foil extends onto
the opposite surface surrounding the spout, and welding the foil to
the flange.
Description
BACKGROUND OF THE INVENTION
[0001] The present invention relates to closures for aseptic and
extended shelf life (ESL) containers and more particularly
paperboard cartons.
[0002] In non-aseptic containers it is well known to use carton
fitments that extend through a wall of a paperboard carton. These
fitments are constructed to provide a pour spout and provide a
resealable closure such as a threaded spout and overcap. They are
typically made of injection-moulded plastics. The fitment may also
provide tamper evidence such as a severable tamper band connecting
a lower edge of the overcap to a body of the fitment. Ring pull
removable membranes are often provided within the spout. A typical
fitment will have a base flange and a cylindrical spout.
[0003] Such fitments are inserted, as fully assembled components
with an overcap fitted, through a hole cut in the top of the
carton. The fitment is passed through the hole from the inside of
the open top during the filling process. The base flange, being
larger than the diameter of the hole, remains inside the carton.
Ultrasound welding is used to weld the base flange to the carton
and secure the fitment in place. Fitments of this type are used
extensively to enable gable top paperboard cartons to be
resealable. They are typically used for fresh milk and fresh juice,
which are not packed aseptically.
[0004] Aseptic Packaging
[0005] In aseptic filling a UHT process is used to process the
product prior to filling. The product is subjected to high
temperature (140.degree. C.) for a very short period (4 seconds)
and then cooled to a temperature between ambient and 4 degrees C.
Once cooled the product must remain in sterile conditions and
cannot be exposed to environmental air or bacteria. The cartons and
fitments must also be cleaned and sterilised, typically using
Hydrogen Peroxide or peracetic acid, which is later evaporated off
the components. The cartons are then filled and sealed in an
aseptic environment. The packaging must also be sealed tightly
enough to prevent re-infection. This process is effective to
provide long shelf-life products. The cost of the filling plant is
significant.
[0006] ESL packaging covers other processes such as microfiltering
to ensure minimal microbe presence in the product.
[0007] A significant feature of both aseptic and ESL cartons is the
presence of a continuous barrier layer. This layer is required to
prevent bacteria, microbes, yeasts or fungal spores passing into
the container and to provide a gas barrier. The use of existing
carton fitments that require a pre-cut hole in the carton blank is
clearly not possible.
[0008] Cartons for use in aseptic packaging are typically
constructed of several layers. In one example there are seven
layers that make up the aseptic package. From the outside in they
are--polyethylene, adhesive, paper, adhesive, aluminium foil,
adhesive and polyethylene. The aluminium foil provides a barrier
layer. The adhesive layers serve to adhere the materials together
and the polyethylene layers serve to provide surface coatings.
These layered structures are described as composite paperboard. The
barrier layer may alternatively be made of EVOH.
[0009] The original aseptic cartons were composite paperboard
tetrahedrons and later bricks, which were difficult to open and
could not be resealed. Aseptic cartons are now provided with carton
fitments that offer reclosable, tamper-evident screw overcap
closures as with paperboard cartons. In order to maintain the
barrier layer, two methods have been employed.
[0010] In the first method a hole is cut in the outer paper and
plastics layers of the composite paperboard blank before the blank
is laminated with a barrier and inner layers. The fitment is then
applied to the exterior of the carton and must incorporate a
mechanism for cutting, tearing or punching through the barrier and
inner layers. In the second method the composite paperboard is
scored or weakened without penetrating the barrier layer at the
position where the carton fitment is to be placed. The cutting,
tearing or punching mechanism then has to break through all the
layers of the composite paperboard. A great variety of designs have
been proposed for this mechanism. These range from pivoting levers;
ratchets that drive teeth down through the paperboard, and punch
thorough systems which require the user to push a thumb down into
the spout. Examples of such post applied carton fitments are
described in EP-A-1, 127 798 (Rexam), which teaches a cam driven
mechanism; and WO 98/41452 (Tetra Laval), which teaches a ratchet
mechanism and provides a tamper indicator. Numerous other
post-applied fitments are available on the market from
manufacturers such as SIG Combibloc GmbH & Co KG
(www.sigcombibloc.com) and Bericap GmbH & Co
(www.bericap.com).
TECHNICAL PROBLEMS
[0011] All of these fitments suffer from technical problems
including the amount of force needed to open the package and the
relative complexity of manufacture, installation and use,
particularly for fitments assembled from multiple parts. Alignment
issues are a particular problem in post-applied fitments. Since the
fitments need to be glued onto the containers there is a risk that
they will become detached in transit. The external application also
makes these closures vulnerable to tampering. Use of these closures
is frequently not intuitive creating additional problems of
consumer education.
SOLUTION OF THE INVENTION
[0012] Rather than the approach of these prior art fitments, which
retain the barrier layer in the composite paperboard carton, the
present invention solves the problem of providing a continuous
barrier layer with a resealable pour spout closure by providing the
barrier layer within the closure itself so that it can be inserted
into a pre-cut hole as with non-aseptic cartons.
[0013] However in an aseptic/ESL context, it is not acceptable to
expose bare aluminium to the contents of many aseptically packaged
fluids, for example high acid products. This is because such
products have a propensity--over the long shelf life of six to nine
months--to oxidise the metal. Therefore any bare foil must be
prevented from coming into contact with the contents of the aseptic
carton. It is therefore not sufficient to apply a foil--even a
coated foil--to a base flange of a carton fitment, as any exposed
cut edge would be vulnerable to this oxidation over time. It is
known to avoid such contact in the structural seams needed to make
a carton from a composite paperboard blank. Typically to create
such seams, an inner paperboard layer is folded outwardly and
overlapped with an outer layer so that the edges of the barrier
layer foil are prevented from coming into contact with the
contents. The seam is welded by ultrasound or induction heat
sealed. This is found to produce acceptable results.
[0014] Applying a removable, peelable foil seal across a top of a
fitment spout prevents the presence of a plug inside the overcap
for satisfactory reseal and leaves a significant breach in the gas
barrier through the base flange surrounding the spout within the
hole and the spout wall.
[0015] It is therefore preferable to continue the barrier layer in
the base flange of the fitment and this is a solution described in
U.S. Pat. No. 4,948,015 (Kawajiri). The fitment described has a
base flange provided with a recess into which a thin film having a
property of a gas barrier is securely fitted. It is suggested that
the film may be of laminated structure comprising polyethylene,
aluminium and polyethylene layers. The barrier layer has its
peripheral edge concealed by the material of the film. Insert
moulding is suggested as a technique for joining the film to the
fitment. In principle the Kawajiri proposal solves the technical
problems discussed above. However the design is not practicable for
the following reasons: [0016] Practical, high volume, low cost
manufacture of multilayer films containing an entirely embedded
aluminium foil layer (with no exposed aluminium edge) is not known
in the art and no method is described by Kawajiri. [0017] Insert
moulding for such lightweight foil discs would be a slow procedure
requiring careful placement of discs into the mould. [0018] In
order to place the disc into the recess it is almost inevitable
that a crevice would be created within the recess around the disc
and this would render the fitment unsuitable for aseptic use as the
crevice could not be adequately sterilised prior to use. The
inability to kill bacteria hiding in crevices is a major issue that
leads to any packaging subject to this problem being non aseptic,
leading to a product "shelf life" of a few days, rather than the
current aseptic norm of many months shelf life under non
refridgerated conditions.
[0019] In accordance with the present invention the technical
problems left unsolved by Kawajiri are solved by providing a
fitment comprising a base flange and a hollow spout, a removable
part within a base of the spout, and an overcap for resealably
closing the spout, and a barrier foil coated on both sides with a
plastics layer extending across the base flange, characterised in
that the foil has an exposed cut edge prior to assembly in the
fitment and that edge of the foil is assembled to the flange in
such a manner that the edge is prevented in use from coming into
contact with contents of a container to which the fitment is
assembled. The edge can be sealed away in various ways such as, for
example, by embedding it into the plastic of the flange, folding it
underneath prior to sealing to the flange, or wrapping it around a
peripheral edge of the flange.
[0020] Preferably the edge of the foil is embedded in the base
flange. By embedding the edge of the foil into the plastic it
cannot taint the product. Since the barrier layer in the paperboard
carton overlaps with the barrier foil applied to the base flange
there is no break in the barrier layer.
[0021] Such a fitment can be manufactured by a method comprising
the steps of placing a foil having a plastics layer on each surface
within a receiving wall projecting from a first surface of a base
flange of a fitment that has a hollow spout extending from an
opposite surface, and securing the foil to the flange such that the
wall is sealed over the edge of the foil disc.
[0022] The fully assembled fitment may be inserted into a pre-cut
hole in a composite paperboard carton blank from inside prior to
filling and the embedding of the foil edge carried out as part of
the same process as welding the flange to the paperboard.
[0023] Alternatively the present invention provides a fitment
comprising a base flange having a first surface and a hollow spout
projecting from a surface opposite the first surface, a removable
part within a base of the spout, and an overcap for resealably
closing the spout, characterised in that a barrier foil coated on
both sides with a plastics layer is wrapped over the first surface
of the flange such that the foil extends onto the opposite surface
surrounding the spout.
[0024] In this alternative construction the cut edge of the foil is
prevented from coming into contact with the contents of the
container as it is sealed to a paperboard wall during the
ultrasound welding of the fitment into the carton. This seal has
exactly the same construction and integrity as other seals
elsewhere on the paperboard carton. The barrier layer in this
construction is virtually continuous as there are only the inner
polyethylene layers between the two foils and not even the modest
thickness of the base flange as in the earlier variation.
[0025] Preferably the fitments as claimed are used in any shape of
paperboard carton, but it will be appreciated that this type of
fitment could also be applied to a mouth of a gas impervious bottle
such as a barrier PET or multi-layer polyolefin bottle; to a coated
steel or aluminium can or can lid; or to a mono or multi-layer
plastics container which is thermoformed, injection moulded or blow
moulded.
BRIEF DESCRIPTION OF THE DRAWINGS
[0026] In order that the invention may be well understood some
embodiments thereof will now be described, by way of example only,
with reference to the accompanying diagrammatic drawings, in
which:
[0027] FIG. 1 shows a longitudinal section through a fitment in
accordance with a first embodiment of the invention assembled in a
carton top;
[0028] FIG. 2 shows a detail of an edge of the base flange of FIG.
1 prior to insertion of a foil;
[0029] FIG. 3A shows a detail of an alternative embodiment of the
edge of a base flange prior to insertion of a foil;
[0030] FIG. 3B shows a detail of an edge of the base flange of FIG.
3A after insertion of the foil and before an induction heat sealing
step;
[0031] FIG. 4 shows a section through a fitment in accordance with
a further embodiment of the invention; and
[0032] FIG. 5 shows a section through a fitment in accordance with
a yet further embodiment of the invention.
OVERVIEW
[0033] A carton fitment 2 is made up of a base flange 4 with an
upstanding pour spout 6, which is closed by an overcap 8.
[0034] The fitment 2 is two injection moulded plastics
components.
[0035] The spout 6 comprises a hollow cylindrical spout in the base
of which there is a removable part 10. The removable part 10 is a
plastics disc joined to the remainder of the base flange 4 by a
weakened section 12. A ring pull 14 is connected to the removable
part 10 in order to allow the removable part to be removed.
[0036] As so far described, this fitment is substantially similar
to carton fitments known in the art for use with standard
paperboard cartons. Any of the design features employed on such
fitments can be incorporated into the fitment of the present
invention.
[0037] The fitment of the present invention is however intended to
be used with a container providing a barrier layer. As illustrated
in FIG. 1 the fitment is inserted into a pre-cut hole 20 in a
composite paperboard carton wall 22. The fitment 2 could also be
assembled to an open mouth of a barrier PET or polyolefin barrier
layer bottle; or any other gas tight container, such as a tin can
made up of mono or multi layers including aluminium, steel etc
coated with a plastics surface layer, or a plastics container,
which is thermoformed, injection moulded or blow moulded, whether
by an extrusion or injection-stretch blow moulding process.
[0038] A foil disc 30 is sealed to an underside of the base flange
4 and removable part 10.
[0039] Instead of a solid disc, the removable part 10 could be
constructed as an annular frame typically with a central,
three-pointed star structure. Such a frame would be joined by
weekened bridges to the base flange 4. This reduces the overall
weight of the fitment 2.
[0040] The foil disc 30 is cut from an aluminium foil, which is
coated on both sides with a plastics layer, typically polyethylene,
polypropylene or PET, which enables it to be bonded to other
plastics components.
[0041] The base flange 4 is welded in an annular region A to the
carton wall 22 by means of induction heat sealing or ultrasonic
welding. A receiving wall 32 surrounds a peripheral edge of the
base flange 4. In FIG. 1 the receiving wall 32 is shown as having
been deformed inwardly over the peripheral edge of the foil disc 30
in order to prevent the contents of the container being exposed to
an edge of the aluminium layer within the double sided coated foil
disc 30.
[0042] Carton Structure
[0043] The composite paperboard carton 22 is formed from several
layers of material including a gas barrier layer 40. This barrier
layer may be aluminium foil or EVOH or any other suitable material.
The barrier layer is bonded by means of an adhesive layer to a
paperboard layer which is coated on each side by a polyethylene
coating. Other detailed constructions of the composite paperboard
are possible.
[0044] Closure Construction
[0045] One possible construction for the overcap and pour spout is
described in WO99/61337 (Spreckelsen McGeough), which also shows
how a foil may be fitted into a base flange. However, in that
document, the free metal edge of the foil would be exposed.
Spreckelsen McGeough also shows a snap on overcap. It will be
appreciated that the screw on overcap 8 as illustrated is equally
appropriate for closing the pour spout 6. The overcap 8 is shown as
having a plug 42, which is received within an open mouth of the
spout 6 in order to ensure effective resealing. Threads 44, 46 are
formed on the external wall of the spout of the pour spout 6 and on
a facing internal wall of the overcap 8 in order to enable the
overcap to be screwed onto the spout of the spout.
[0046] Sealing the Edge of the Foil
[0047] An essential feature of the fitment of the present invention
is that the metal edge of the foil is prevented from coming into
contact with the contents of a container in use when the fitment is
assembled. The fitment 2 is preferably pre sealed to the foil 30
before installation in the container. In the embodiment of FIGS. 1
and 2 the foil disc 30 is seated within a receiving wall 32 which,
prior to assembly of the foil to the spout 6, depends vertically
from the base flange 4 as shown in FIG. 2. During assembly a tool
is used to press the receiving wall 32 over the edge of the foil
disc during an induction heat sealing process. The receiving wall
32 is therefore a sacrificial part of the spout construction and
the plastic making up this material effectively melts over the edge
of the foil to seal in the exposed metal edge.
[0048] An alternative construction of the receiving wall 32 is
shown in FIGS. 3A and 3B. In this arrangement the wall 32 has a
weaked portion 50 in an intermediate annular region. Once the foil
disc 30 is inserted within the receiving wall 32 the weakened
portion 50 allows a terminal end 52 of the wall to be deformed
inwardly over the edge of the foil to retain it in position to
ensure that the plastic of this sacrificial receiving wall 52 flows
over and covers any exposed metal edge.
[0049] An alternative approach to sealing away the metal edge of
the foil 30 is shown in FIG. 4. In this embodiment the foil 30 is
larger than the diameter of the base flange and is wrapped over the
entirety of a lower first surface 54 of the base flange 4 around a
free edge and onto a second surface 56 of the base flange. The
folded edge terminates inwardly of the annular region A at which
the base flange 4 is welded to the container 22.
[0050] In the embodiment of FIG. 5 the foil disc 30 has its edges
folded upwardly and inwardly prior to being welded to the base
flange 4. This folding step may be done by means of an appropriate
forming tool during placement of the foils on the base flange 4. A
periphery of the base flange 4 is provided with a retaining wall 34
to retain the folded foil disc in place prior to sealing.
[0051] Method of Manufacturing
[0052] The carton fitments 2 are preassembled to the foil disc 30
and the foil welded in position by an induction heat sealing
process before the fitments are assembled to the paperboard carton.
The assembly to the paperboard carton is as with standard
non-aseptic packaging and will not be described in detail here. As
an alternative to induction heat sealing of the foil to the base
flange 4, ultrasonic welding may be employed. The foil may also be
secured to the flange by adhesive means. In the embodiment of FIG.
4, it is possible to rely on the wrapping over of the outer
peripheral edge of the foil around the base flange 4 to secure the
foil to the spout 6. Although further bonding steps can be
undertaken prior to installation in the carton, these are not
essential with this embodiment. If the fitment 2 is induction heat
sealed to the carton the foil 30 will weld to the base flange at
that time.
[0053] In the embodiment of FIG. 4 the seal which is created
between the edge of the foil 30 and the wall 22 is of exactly the
same construction as on the other seams elsewhere in a paperboard
carton of this type.
[0054] Continuity of the Barrier Layer
[0055] Once the fitment 2 is welded into hole 20 in the paperboard
carton wall 22 the barrier layer constituted by the foil 30 creates
a continuous barrier layer with the layer 40 within the paperboard
carton. Therefore, the ease of assembly advantages of the carton
fitments used with non-aseptic packaging are combined with the
integrity of the barrier layer offered by post applied prior art
fitments traditionally used with aseptic packaging.
[0056] Consumer Use
[0057] In use, a consumer can open the packaging by removing the
overcap 8 by unscrewing it in order to gain access to the ring pull
14. The removable part 10 can then be removed by use of the ring
pull 14. Since the foil 30 is welded to the whole of the base
flange 4 including the removable part 10, the pulling out of the
ring pull will breach the foil and allow access to the container
contents. If necessary, teeth may be formed in the lower surface 54
of the base flange 4 in order to facilitate tearing of the foil as
described in Spreckelsen McGeough above. If the foil is not severed
by removal of the removable part 10, it is relatively easy for this
foil layer to be punctured manually.
[0058] Although a ring pull has been shown, any of the other prior
art mechanisms can be used in the spout to remove the removable
part and breach the foil to allow access to the contents.
* * * * *