U.S. patent application number 11/151028 was filed with the patent office on 2005-12-29 for autoclavable reclosable package.
This patent application is currently assigned to Reynolds Consumer Products, Inc.. Invention is credited to Melchoir, Greg W., Sprague, Paul A..
Application Number | 20050286812 11/151028 |
Document ID | / |
Family ID | 32474591 |
Filed Date | 2005-12-29 |
United States Patent
Application |
20050286812 |
Kind Code |
A1 |
Sprague, Paul A. ; et
al. |
December 29, 2005 |
Autoclavable reclosable package
Abstract
A reclosable package that seals an enclosed product and allows
the product to be subjected to a retort procedure to cook the
product while the product is in the package. The reclosable package
is formed from a polypropylene film and includes a zipper closure
including a pair of mating closure profiles both formed from a
polypropylene material. One of the male or female closure profiles
includes a sealing flange having a layer of sealant such that the
sealing flange provides a seal for the package below the
interaction between the closure profiles. This seal prevents the
product from migrating through the profile member during the retort
procedure and prior to the package being opened for the first
time.
Inventors: |
Sprague, Paul A.; (Kiel,
WI) ; Melchoir, Greg W.; (Green Bay, WI) |
Correspondence
Address: |
ECKERT SEAMANS CHERIN & MELLOTT, LLC
ALCOA TECHNICAL CENTER
100 TECHNICAL DRIVE
ALCOA CENTER
PA
15069-0001
US
|
Assignee: |
Reynolds Consumer Products,
Inc.
|
Family ID: |
32474591 |
Appl. No.: |
11/151028 |
Filed: |
June 13, 2005 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
11151028 |
Jun 13, 2005 |
|
|
|
10726731 |
Dec 2, 2003 |
|
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|
60430727 |
Dec 3, 2002 |
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Current U.S.
Class: |
383/61.2 ;
383/203; 383/210 |
Current CPC
Class: |
B65D 33/2525 20130101;
B65D 33/2508 20130101; B65D 33/2533 20130101; B65D 81/34
20130101 |
Class at
Publication: |
383/061.2 ;
383/203; 383/210 |
International
Class: |
B65D 033/16; B65D
033/00; B65D 065/26 |
Claims
What is claimed is:
1. A flexible, reclosable package for containing a product and
allowing the product to be subjected to a retort process while
within the reclosable package, comprising: a pair of side panels
joined along a first side edge and a second side edge, the side
panels defining a mouth providing access to a package interior,
wherein the side panels are formed from polypropylene; and a
reclosable zipper positioned along the mouth of the package for
selectively opening and closing the package mouth, the reclosable
zipper including a first closure profile attached to the first side
panel and a second closure profile attached to the second side
panel, wherein the first and second closure profiles are each
constructed and arranged to interlock each other to hold the mouth
in a closed position, wherein the reclosable zipper is formed from
polypropylene, wherein the first closure profile includes a sealing
flange having a sealant, wherein the sealant of the sealing flange
is attached to the second side panel opposite the first closure
profile during the retort process to provide a hermetic seal
between the sealing flange and the second side panel.
2. The reclosable package of claim 1 further comprising a line of
weakness positioned between the sealing flange and an attachment
flange of the first closure profile, wherein the sealing flange
separates from the attachment flange along the line of weakness and
remains attached to the second side panel of the reclosable package
upon initial opening of the reclosable package.
3. The reclosable package of claim 2 wherein the sealant is a
polypropylene-based sealant.
4. The reclosable package of claim 1 wherein the sealant is a
releasable sealant such that the sealant separates from the second
side panel to permit the sealing flange to separate from the second
side panel upon initial opening of the product package.
5. The reclosable package of claim 2 wherein the sealing flange
includes a plurality of lines of weakness positioned between the
attachment flange and an outer end of the sealing flange.
6. The reclosable package of claim 1 wherein the sealant is applied
to a first face surface of the sealing flange and a second sealant
is applied to an opposite, second face surface of the sealing
flange, wherein the second sealant engages the first side
panel.
7. The reclosable package of claim 6 wherein the second sealant is
a permanent sealant and the first sealant is a releasable sealant
such that the sealing flange separates from the second side panel
and remains attached to the first side panel upon initial opening
of the product package.
8. The reclosable package of claim 1 wherein the second closure
profile includes a second sealing flange, the second sealing flange
having a second sealant, wherein the first sealing flange and the
second sealing flange engage each other to provide a hermetic seal
across the package interior.
9. The reclosable package of claim 8 wherein the first sealant and
the second sealant are each a releasable sealant.
10. The reclosable package of claim 8 wherein the first and second
sealing flanges are movable relative to the first and second side
panels.
Description
CROSS REFERENCE TO RELATED APPLICATION
[0001] The present application is a divisional of application Ser.
No. 10/726,731, filed on Dec. 2, 2003, which claimed the benefit of
U.S. Provisional Patent Application Ser. No. 60/430,727, filed on
Dec. 3, 2002, both disclosures of which are fully incorporated by
reference herein.
FIELD OF THE INVENTION
[0002] The present invention generally relates to a package having
a reclosable zipper member positioned at the mouth of the package
to allow the package to be reclosed after initial opening. More
specifically, the present invention relates to a zipper closure
that hermetically seals the contents of the package and can
withstand the temperatures associated with a retort procedure.
BACKGROUND OF THE INVENTION
[0003] Many packaging applications use reclosable containers to
store various types of articles and materials. These packages may
be used to store and ship food products, non-food consumer goods,
medical supplies, waste materials, and various other types of
articles. Reclosable packages are convenient in that they can be
closed and resealed after the initial opening to preserve the
enclosed contents. The need to locate a storage container for the
unused portion of the product in the package is thus avoided. As
such, providing products in a reclosable package appreciably
enhances the marketability of these products.
[0004] Although reclosable packages have been around for quite some
time and are used for storing various types of food products,
currently available reclosable packages are not constructed to be
used with food products that are subjected to a retort procedure
after the food products have been placed into the reclosable
package. During the retort procedure, the contents of the package
are typically subjected to temperatures of 255.degree. F. for a
specified period of time to cook the food in its own package,
thereby extending shelf life and insuring food safety. Food items
such as tuna are often subjected to this type of retort
procedure.
[0005] Currently available reclosable packages cannot withstand the
temperature requirements of the retort procedure. Specifically, the
zipper closure used across the open mouth of the package is
typically formed from a polyethylene material that cannot withstand
the temperatures required for the retort or autoclave sterilization
process.
[0006] Further, packages used during a retort procedure are made
from a polypropylene film that can withstand the temperature of the
retort procedure. Currently available zipper closures made from
polyethylene do not form an adequate bond with the polypropylene
film and thus cannot be used for a sealed package.
[0007] Food products that are contained within a reclosable package
that are subjected to the retort procedure must be hermetically
sealed to prevent contamination. Thus, the zipper closure across
the mouth of the package must provide a hermetic seal across the
width of the package in order to prevent contamination of the
enclosed products before the package is initially opened.
Typically, the snap fit between the male and female profile
elements of a zipper closure does not provide a hermetic seal.
[0008] During the retort procedure, the contents of the package,
such as food particles or liquids, have a tendency to migrate
through the mated closure profile and into the package header area
of the pouch. When a user tears the pouch header open, the consumer
then handles the gripping area above the closure profiles in order
to separate the individual members of the zipper closure. Since
many products contained within a retort package are messy and
possibly greasy, accessing the package interior through the zipper
closure becomes more difficult if the product migrates past the
closure profile members.
[0009] Therefore, it is an object of the present invention to
provide a reclosable package having a zipper closure formed from a
material that can withstand the temperatures during the retort
procedure. Further, it is an object of the present invention to
provide a reclosable package that provides a hermetic seal across
the package mouth to prevent contamination of the enclosed products
prior to the initial opening of the reclosable package.
[0010] Yet a further object of the present invention is to provide
a reclosable package that prevents the migration of the packaged
food product past the zipper closure prior to opening of the
reclosable package.
SUMMARY OF THE INVENTION
[0011] The present invention is a reclosable package that allows
the contents of the package to be subjected to a retort procedure
while the product is contained within the package. Further, the
product package provides a hermetically sealed enclosure that
includes a tamper evident feature such that a user can determine if
the package has been previously opened. The product package further
prevents the migration of the packaged food product past the zipper
closure during the retort procedure and prior to opening of the
releasable package.
[0012] The reclosable package is formed from a packaging film that
is shaped into a reclosable package using conventional bag forming
techniques. However, the packaging film used to create the
reclosable package of the present invention is preferably a
polypropylene material that can withstand the retort temperatures
of 255.degree. F. for up to 84 minutes.
[0013] The product package includes mating male and female closure
profiles formed on opposite side panels of the product package. The
male and female closure profiles mate with each other to allow the
product package to be repeatedly opened and reclosed by a user. In
the reclosable package of the present invention, both of the male
and female closure profiles are formed from a polypropylene
material such that the closure profiles can be bonded to the
polypropylene side panels. The male and female closure profiles can
be bonded to the side panels using either heat alone or heat in
combination with a sealant placed between the closure profiles and
the side panels. Preferably, the sealant is a polypropylene-based
adhesive resin that provides for a strong bond between the closure
profiles and the side panels.
[0014] In accordance with a first embodiment of the invention, one
of the closure profile members includes a sealing flange that
extends from an attachment flange used to secure the profile to the
side panel of the product package. The sealing flange is separated
from the attachment flange by a die line or other line of weakness
such that the sealing flange can flex relative to the attachment
flange. Preferably, the sealing flange includes a layer of sealant
on its inner surface.
[0015] During the formation process of the product package, the
sealant on the sealing flange is attached to the side panel
opposite the side panel to which the closure profile including the
sealing flange is attached. In this manner, the sealing flange
provides for a hermetic seal along the entire width of the product
package. This seal prevents the product from migrating into contact
with the zipper closure during the retort procedure.
[0016] The sealant used on the sealing flange is selected such that
the sealant forms a bond with the side panel that both provides a
hermetic seal and is strong enough to allow the sealing flange to
separate from the closure profile along the line of upon initial
opening of the product package.
[0017] In an alternate embodiment of the invention, the closure
profiles attached to the opposed side panels of the product package
are joined to each other by a pair of connector flanges. Thus, the
pair of closure profiles and connector flanges are formed as a one
piece structure. The connector flanges are separated from each
other by a reduced material thickness die line such that the
closure profile can be separated along the die line.
[0018] The attachment of the pair of closure profiles along the die
line in the alternate embodiment of the invention provides for a
hermetic seal beneath the interacting portions of the closure
profile. Thus, the product contained within the product package is
hermetically sealed and prevented from migrating past the zipper
closure, regardless of the state of interaction between the
interlocking members of the closure profile. In the alternate
embodiment of the invention, the closure profiles and the side
panels of the reclosable package are both formed from a
polypropylene material that can withstand the temperatures
associated with the retort procedure.
BRIEF DESCRIPTION OF THE DRAWINGS
[0019] The drawings illustrate the best mode contemplated of
carrying out the present invention. In the drawings:
[0020] FIG. 1 is a side view of a flexible, reclosable package
having the zipper closure of the first embodiment of the present
invention in an open condition prior to product loading;
[0021] FIG. 1a is a magnified section view of the zipper closure of
FIG. 1;
[0022] FIG. 2 is a side view illustrating the loading of a product
into the reclosable package including the zipper closure of the
present invention;
[0023] FIG. 3 is a side view illustrating the reclosable package in
a sealed condition including a product such that the product can be
subjected to the retort procedure;
[0024] FIG. 4 illustrates the removal of a header from the product
package prior to initial opening;
[0025] FIG. 5 is a side view illustrating the separation of the
sealing flange from the closure profile along the line of weakness
during the initial opening of the product package;
[0026] FIG. 6 is a side view of a second embodiment of the zipper
closure;
[0027] FIG. 6a is a magnified view of the second embodiment of the
zipper closure shown in FIG. 6;
[0028] FIGS. 7a-7c are side views of a third embodiment of the
zipper closure and illustrate the sealing of the zipper across the
package interior and the separation of the sealing flange from the
package sidewall during the initial opening of the product
package;
[0029] FIGS. 8a-8c are side views of a fourth embodiment of the
zipper closure illustrating the attachment of the sealing flange
across the open package interior and the separation of the sealing
flange from the package sidewall during the initial opening of the
product package.
[0030] FIGS. 9a-9c are side views of a fifth embodiment of the
zipper closure showing the attachment of the sealing flange across
the package interior and the separation of the sealing flange from
the sidewall during the initial opening of the product package;
[0031] FIGS. 10a-10d are side views illustrating a sixth embodiment
of the zipper closure and further showing the attachment of the
sealing flange across the open package interior and the separation
of the sealing flange from the sidewall during the initial opening
of the product package;
[0032] FIGS. 11a-11b are side views of a seventh embodiment of the
zipper closure;
[0033] FIGS. 12a-12c are side views of an eighth embodiment of the
zipper closure and illustrate the connection of a pair of sealing
flanges and the separation of the sealing flanges during the
initial opening of the product package;
[0034] FIGS. 13a-13c are side views of the ninth embodiment of the
zipper closure and illustrate the interconnection between a pair of
sealing strips and the separation of the sealing strips during the
initial opening of the product package;
[0035] FIGS. 14a-14c illustrate a tenth embodiment of the zipper
closure and illustrate the attachment of the zipper closure to the
package sidewalls;
[0036] FIGS. 15a-15c are side views of an eleventh embodiment of
the zipper closure and illustrate the separation of the sealing
flange from the closure profile during the initial opening of the
product package;
[0037] FIG. 16a is a side view of yet another embodiment of a
zipper closure that can withstand the retort procedure and provide
a hermetically sealed product package;
[0038] FIG. 16b is a magnified view of the area illustrated by line
16-16 in FIG. 16a;
[0039] FIG. 17 is a side view illustrating the bottom filling of
the reclosable package including the embodiment of the zipper
closure of FIG. 16a;
[0040] FIG. 18 is a side view illustrating the sealing of the
reclosable package prior to the retort procedure;
[0041] FIG. 19 is a view illustrating the removal of the package
header prior to initial opening the reclosable package;
[0042] FIG. 20 is a magnified view illustrating the initial opening
of the reclosable package;
[0043] FIG. 21 is a side view illustrating the separation of the
zipper closure profile elements along a die line to provide access
to the product contained within the reclosable package;
[0044] FIG. 22 is a side view of an alternate embodiment of a
zipper closure for a bottom-fill reclosable package that can
withstand the retort process;
[0045] FIG. 23 is another embodiment of a zipper closure for a
bottom filled reclosable package that can withstand the retort
process;
[0046] FIG. 24 is another embodiment of a zipper closure for a
bottom filled reclosable package that can withstand the retort
process;
[0047] FIG. 25 is another embodiment of a zipper closure for a
bottom filled reclosable package that can withstand the retort
process;
[0048] FIG. 26 is another embodiment of a zipper closure for a
bottom filled reclosable package that can withstand the retort
process;
[0049] FIG. 27 is another embodiment of a zipper closure for a
bottom filled reclosable package that can withstand the retort
process; and
[0050] FIG. 28 is another embodiment of a zipper closure for a
bottom filled reclosable package that can withstand the retort
process.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
[0051] Referring first to FIG. 1, thereshown is a reclosable
package 10 of the present invention. The reclosable package 10 is
formed from a first and a second polymeric film side panels 12 and
14 defining an open interior 16. In the embodiment of the invention
illustrated, the side panels 12 and 14 are joined to each other by
a gusseted bottom wall 18 that allows the open interior 16 of the
reclosable package 10 to expand. Although the reclosable package 10
is illustrated in FIG. 1 as having the gusseted bottom 18, it
should be understood that the reclosable package 10 could be formed
without the gusseted bottom while operating within the scope of the
present invention.
[0052] As illustrated in FIG. 1, the package 10 has an open mouth
20 defined by the top edges 22, 24 of the side panels 12 and 14.
The open mouth 20 allows a user access to the open interior 16 of
the package 10 and allows for a product to be loaded into the
package 10.
[0053] As illustrated in FIG. 1, a zipper closure 26 is attached to
the package near the open mouth 20 and extends across the entire
width of the package between a pair of side edges (not shown). The
zipper closure 26 can include a variety of configurations and
structures while operating within the present invention, a number
of which will be set forth below.
[0054] In the embodiment of the invention illustrated in FIG. 1,
the zipper closure 26 includes a male closure profile 28 and a
mating female closure profile 30. Specifically, the male closure
profile 28 includes a male closure post 32 that is received within
a groove 34 formed between a pair of female closure posts 36 and
38. The mating interaction between the male closure post 32 and the
pair of female closure posts 36, 38 provide for an interlocking
seal between the pair of closure profiles 28 and 30. The specific
construction and design of the male closure post 32 and the female
closure post 36 and 38 is shown for illustrative purposes only and
does not limit the scope of the present invention. It should be
understood that many various configurations for providing an
interaction between the male closure profile 28 and the female
closure profile 38 are thought to be within the scope of the
present invention.
[0055] Referring now to FIG. 1a, in the preferred embodiment of the
invention, the male closure profile 28 includes a sealing flange 40
that extends from the attachment flange 42 of the male closure
profile 28. The sealing flange 40 is integrally extruded along with
the attachment flange 42 and the male closure post 32 and is
separated from the attachment flange 42 by a reduced material
thickness die line 44. Thus, the sealing flange 40 can pivot
relative to the attachment flange 42 about the die line 44.
Although the sealing flange 40 is shown attached to the male
closure profile 28, it should be understood that the sealing flange
40 could also be formed on the female closure profile 30 while
operating within the scope of the present invention. Most
importantly, the sealing flange 40 extends from one of the side
panels 12 or 14 to the opposing side panel to provide a hermetic
seal below the interaction between the closure profiles as will be
made clear below.
[0056] The sealing flange 40 includes a layer of sealant 46 applied
to its front surface 48. Preferably, the sealant 46 is applied to
the front surface 48 of the sealing flange 40 after the extrusion
of the male closure profile 28 and prior to installation of the
closure profile 28 to the side panel 12.
[0057] As illustrated in FIG. 1a, both the male closure profile 28
and the female closure profile 30 are applied to one of the side
panels 12, 14 of the product package. In the embodiment of the
invention illustrated, the side panels 12 and 14 are formed from a
polymeric material that can withstand the temperatures associated
with a retort procedure. Typically, the retort procedure occurs at
approximately 255.degree. F. for 84 minutes or more. The side
panels 12, 14 illustrated in FIG. 1a are formed from a
polypropylene material such that the side panels 12, 14 can
withstand the retort procedure.
[0058] Referring now to FIG. 2, thereshown is the filling of the
reclosable package 10 by a product 50. As illustrated, the product
50 is directed through the open mouth 20 of the reclosable package
and is received within the open interior 16. As illustrated in FIG.
2, the product 50 flows past the zipper closure 26, including the
male closure profile 28 and the female closure profile 30.
[0059] Once a desired amount of product 50 has been placed into the
reclosable package 10, the mouth of the package 20 is closed and
the side panels 12 and 14 heat sealed to each other along the top
seal 52 near the top edge of each panel, as illustrated in FIG. 3.
During the sealing of the top edges, the male closure post 32 may
or may not be mated with the pair of female closure posts 36 and
38. Thus, after the product has been placed into the reclosable
package 10, the top seal 52 close the open interior 16. However,
the package 10 is not hermetically sealed due to the lines of
perforation 58 that separate the header 56 from the remainder of
the package.
[0060] During creation of the top seal 52, the sealant 46 is
pressed into contact with the inner surface 54 of the side panel
14. As illustrated in FIG. 3, the sealing flange 40 is thus
attached to the side panel 14 opposite the side panel 12 to which
the remaining portion of the male closure profile 28 is secured. In
the preferred embodiment of the invention, the composition of the
sealant 46 is selected such that the sealant 46 can be heat sealed
to the inner surface 54 of the side panel 14 during the closure of
the open mouth 20. The sealant 46 is selected such that the
interaction between the sealant 46 and the inner surface 54
provides a hermetic seal between the sealing flange 40 and the side
panel 14.
[0061] In the preferred embodiment of the invention, the side
panels 12 and 14 are formed from polypropylene and the sealant 46
is a polypropylene-based adhesive resin. One example of such a
sealant is the Admer.RTM. QF552A, which is an anhydride modified
copolymer polypropylene-based adhesive resin and available from
Mitsui Chemical America, Inc. The sealant 46 has a melt flow value
in the range of 5.0 to 9.5 g/10 min based on the ASTM test method
D1238. Further, the sealant 46 preferably has a density in the
range of between 0.85 and 0.93 g/cm.sup.3 based upon the ASTM test
method D1505.
[0062] An important consideration for the sealant 46 in the first
embodiment of the invention is that the sealant is able to provide
a hermetic seal between the sealing flange 40 and the side panel 14
yet withstand the retort procedure. Typically, the retort procedure
occurs at 255.degree. F. for the required period of time to cook
the food product while it is in the package. The retort procedure
may last as long as 84 minutes or more. During the autoclave and
sterilization procedures, the sealant must maintain its integrity
and remain attached to the side panel 14 to provide a hermetic
seal.
[0063] As illustrated in FIG. 3, when the sealing flange 40 is
attached to the side panel 14, the product 50 within the open
enclosure can be subjected to the retort procedure. During this
procedure, the product 50 is cooked in the package and harmful
bacteria or other contaminants are killed. This type of retort
procedure is typically associated with fresh food products, such as
tuna or other perishable items.
[0064] In accordance with the present invention, the closure
profiles 28 and 30 are formed from a specified material such that
the profiles 28 and 30 can withstand the retort procedure and bond
to the polypropylene side panels 12 and 14. In prior art available
reclosable packages, the closure profiles are formed from a
polyethylene material having properties that cannot withstand the
autoclave procedure and do not bond well to the polypropylene side
panels 12 and 14.
[0065] In the present invention including the alternate embodiments
to be described below, the male and female closure profiles 28 and
30 are formed from a random copolymer polypropylene that can
withstand the retort process. Specifically, the reclosable profiles
28 and 30 are formed from a material having a melt index in the
range between 1.7 and 3.5 g/10 min as measured using the ASTM test
method D1238. Further, the polypropylene material used to form the
closure profiles 28 and 30 has a density in the range between 0.895
to 0.910 g/cm.sup.3 as measured by the ASTM test method D1505. An
example of such a product is the Atofina.RTM. copolymer product
number 6289MZ. However, other types of polymer materials are
contemplated as being within the scope of the present
invention.
[0066] As can be understood by the above description, it is
important that the material selected for the male closure profile
28 and the female closure profile 30 be able to withstand
temperatures of approximately 255.degree. F. for up to an 84 minute
period.
[0067] In the embodiment of the invention illustrated in FIG. 3,
the male and female closure profiles 28 and 30 can be attached to
the side panels 12 and 14 either solely through the application of
heat or through the combination of heat and a sealant layer between
the closure profiles 28, 30 and the side panels 12, 14. If a
sealant layer is used, the sealant is typically the same as the
sealant 46 applied to the sealing flange 40. Thus, a hermetic seal
is also created between each of the closure profiles 28, 30 and the
side panels 12, 14, as well as along the line of sealant 46.
[0068] Once the product 50 has been subjected to the retort
procedure when it is contained within the reclosable package 10,
the reclosable package 10 including the products 50 can be shipped
to consumers. Upon receipt, the consumer can open the reclosable
package by grasping the top tear off header 56, as illustrated in
FIG. 4. Referring back to FIG. 3, the top tear off header 56 is
separated from the remaining portions of the side panels 12 and 14
by lines of perforation 58 contained in each of the side panels 12
and 14. Once the top tear off header 56 has been separated, the
user can access the pair of closure profiles 28 and 30.
[0069] As can be understood by the above description, the seal
between the sealing flange 40 and the side panel 14 prevents the
food product 50 from migrating through the zipper closure and into
contact with the gripping ridges 60 formed on the pair of closure
profiles 28 and 30, as illustrated in FIG. 4. Since the food
product contained within the package may be greasy or messy, the
prevention of the migration of the food product past the zipper
closure allows the user to more easily grasp the gripping ridges 60
to open the package.
[0070] Referring now to FIG. 5, once the user has grasped the
gripping ridges 60, the male and female closure profiles 28 and 30
can be pulled apart to open the mouth 20 as illustrated. As the
mouth 20 is opened, the sealing flange 40 separates from the
attachment flange 42 along the die line 44 and remains attached to
the side panel 14, as illustrated in FIG. 5. In the embodiment of
the invention illustrated, the sealant 46 forms a sufficiently
strong bond with the side panel 14 such that the sealing flange 40
separates from the attachment flange 42 before the sealing flange
40 is released from the side panel 14. Thus, in addition to
providing a seal to prevent product migration past the zipper
closure, the combination of the sealing flange 40 and the sealant
46 acts as a tamper evident feature for the opening of the product
package 10.
[0071] After the sealing flange 40 has been separated, the product
50 can be removed through the open mouth 20 and the package 10
resealed by re-engaging the male closure profile 28 and the female
closure profile 30.
[0072] Referring now to FIG. 6, thereshown is an alternate
embodiment of the male closure profile 28. In the second
embodiment, the sealing flange 62 has a semi-circular configuration
and includes a pair of die lines 64 and 66. The sealing flange 62
is attached to the attachment flange 42 and separates from the
attachment flange 42 when the product package 10 is opened for the
first time.
[0073] As can be seen in FIG. 6a, the sealant 46 is applied to the
outer end 68 of the sealing flange 66 and contacts the side panel
14 to form a hermetic seal between the sealing flange 62 and the
side panel 14. In the embodiment of the invention illustrated in
FIG. 6, the sealant 46 and the closure profiles 28 and 30 are
formed from the same material illustrated and described in FIGS.
1-5.
[0074] Referring now to FIGS. 7a-7b thereshown is another alternate
embodiment for the zipper closure to be used across the open mouth
20 of a product package that can be subjected to the retort
process. The zipper closure includes a male closure profile 28 and
a female closure profile 30 that are designed to mate and engage to
hold the open mouth 20 closed. In the embodiment of the invention
illustrated, the male closure profile includes a depending sealing
flange 86. The sealing flange 86 includes a layer of releasable
sealant 88 on its first face surface 90 and a layer of permanent
sealant 92 on the opposite, second face surface 94. In the
embodiment of the invention illustrated, the permanent sealant 92
has the same composition as the sealant 46 included on the sealing
flange 40 shown in FIG. 5.
[0075] When the reclosable package 10 is in the closed position
shown in FIG. 7b, the permanent sealant 92 is in contact with the
side panel 14 while the releasable sealant 88 contacts the side
panel 12. In this position, the sealing flange 86 prevents product
from seeping past the closures and contacting the gripping ridges
60. When the reclosable package 10 is opened for the first time, as
illustrated in FIG. 7c, the sealing flange 86 separates from the
side panel 12 along the releasable sealant 88. Thus, the releasable
sealant 88 forms a "peel seal" between the sealing flange 86 and
the side panel 12. In the preferred embodiment of the invention,
the releasable sealant 88 is an FDA approved sealant.
[0076] Referring now to FIGS. 8a-8c, thereshown is yet another
embodiment of the zipper closure positioned along the mouth 20 of
the reclosable package 10. In the embodiment of the invention
illustrated, the male closure profile 28 includes a sealing flange
96. The sealing flange 96 is formed integrally with the remaining
portions of the male closure profile 28 and includes a releasable
sealant 98 applied to the front face 100 of the sealing flange 96.
As illustrated in FIG. 8b, the releasable sealant 98 creates a seal
between the sealing flange 96 and the side panel 12 to prevent the
product from seeping between the closure profiles prior to opening.
When the package 10 is opened for the first time, as shown in FIG.
8c, the releasable sealant 98 separates from the side panel 12 and
allows for access to the contents of the package. As discussed
above in the embodiment shown in FIGS. 7a-7c, the releasable
sealant 98 is preferably an FDA approved sealant for contact with
food products.
[0077] Referring now to FIGS. 9a-9c, thereshown is yet another
embodiment of a method for creating the reclosable package 10. In
the embodiment of the invention illustrated, the zipper closure 26
is initially installed in a mated condition. Specifically, the male
closure profile 28 and the female closure profile 30 are installed
in the mated condition shown in FIG. 9a. As shown, the female
closure profile 30 is initially attached to the side panel 12
through the application of heat or an adhesive while the male
closure profile 28 is spaced from the side panel 14. When the
zipper closure 26 is in the position shown in FIG. 9a, product can
be fed into the package interior 16 through the opening 95 that
exists between the side panel 14 and the male closure profile
28.
[0078] Once the package has been filled, the male closure profile
28 is attached to the side panel 14 through the application of heat
or an adhesive. At the same time, the sealing flange 96, including
the releasable sealant 98, is secured to the opposite side panel
12. As can be understood in FIGS. 9a and 9b, the method of the
invention allows the product to be filled past the zipper, rather
than through the zipper as in the previously described embodiment
of FIGS. 8a-8c.
[0079] When the reclosable package 10 is opened for the first time,
the sealing flange 96 separates from the side panel 12 along the
layer of releasable sealant 98.
[0080] Referring now to FIGS. 10a-10c, thereshown is yet another
embodiment of the invention similar to the embodiment shown in
FIGS. 9a-9c. As described above, the zipper closure 26 is initially
installed in a mated condition and product is fed into the open
interior 16 through the opening 95 between the side panel 14 and
the male closure profile 28. However, in the embodiment shown in
FIG. 10a, the sealing flange 96 is separated from the remaining
portions of the male closure profile 28 by a line of weakness 100.
Additionally, the sealing flange 96 includes a permanent sealant
102 that creates a bond with the side panel 12, as shown in FIG.
10b.
[0081] When the reclosable package 10 is opened for the first time,
the sealing flange 96 separates from the remaining portions of the
male closure profile 28 along the line of weakness 100 to provide
access to the open interior 16. The permanent sealant 102 is
sufficiently strong to cause the separation of the sealing flange
96 from the male closure profile 28 upon initial opening. In the
embodiment shown in FIGS. 10a-10c, the permanent sealant 102 is the
same composition as the sealant 46 shown in the first embodiment of
FIG. 1a.
[0082] Referring now to FIGS. 11a-11b, thereshown is yet another
embodiment of a zipper closure 104. In the embodiment of the
invention shown in FIG. 11a, the zipper closure 104 includes a male
profile element 106 and a female profile element 108. The male
profile element 106 includes an attachment flange 110 while the
female profile element includes a similar attachment flange 112. As
illustrated, the attachment flanges 110, 112 are joined to each
other along an apex 114. In the preferred embodiment of the
invention, the apex 114 includes a line of weakness such that the
attachment flange 110 can separate from the attachment flange 112
along the apex 114.
[0083] As illustrated in FIG. 11a, the male profile element 106 is
initially attached to the side panel 12 by the application of heat
or an adhesive while the female closure profile 108 is spaced from
the side panel 14 by the opening 95. In this mated, spaced
condition, product can be inserted into the open interior 16 of the
reclosable package 10 through opening 95 and past the zipper
closure 104. Once the product has been inserted, the female profile
element 108 is attached to the side panel 14 by the application of
heat or an adhesive to provide a seal across the mouth of the
package. In the preferred embodiment of the invention, the male and
female profile elements 106, 108 are extruded as one piece and are
joined to each other along the apex 114. During initial product
opening, the male and female profile elements 106, 108 separate
from each other along the apex 114 to provide access to the open
bag interior.
[0084] FIGS. 12a-12c illustrate yet another embodiment of a zipper
closure 26 positioned at the open mouth of the reclosable package
10. In the embodiment illustrated in FIG. 12a, the male closure
profile 28 includes an attachment flange 116 while the female
closure profile 30 includes a similar attachment flange 118. The
attachment flanges 116 and 118 are not adhered to the side panels
12, 14 and each include a releasable sealant 120.
[0085] As illustrated in FIG. 12b, when the package 10 is closed,
the releasable sealants 120 engage each other to provide a hermetic
seal across the entire width of the package 10. In the preferred
embodiment of the invention, the releasable sealant 120 is an FDA
approved releasable sealant.
[0086] As shown in FIG. 12c, when the package 10 is opened for the
first time, the releasable sealant 120 formed on each of the
attachment flanges 118 and 116 separate to provide access to the
open interior of the product package 10.
[0087] FIGS. 13a-13c illustrate yet another embodiment of the
present invention for the creation of a reclosable package 10 that
can withstand the retort process. As illustrated, the side panel 12
includes a first sealant strip 122 while the second side panel 14
includes a second sealant strip 124. The sealant strips 122 and 124
are aligned with each other such that when the reclosable package
10 has been filled, the sealant strips 122 and 124 are brought into
a mating relationship, as shown in FIG. 13b. The interaction
between the sealant strips 122 and 124 provide a continuous seal
across the interior of the reclosable package 10 and prevents
product from migrating past the sealant strips into contact with
the zipper closure 26.
[0088] As shown in FIG. 13c, when the package 10 is opened for the
first time, the sealant strips 122 and 124 separate from each other
to provide access to the open interior 16 of the package 10. In the
preferred embodiment of the invention, the sealant strips 122 and
124 create a peel seal and are formed from the same releasable
sealant as described above.
[0089] FIGS. 14a-14c show alternate methods for attaching yet
another zipper closure across the open mouth of a reclosable
package 10. As illustrated in FIG. 14a, the zipper closure includes
a male closure profile 28 and a female closure profile 30. The male
closure profile 28 includes a sealing flange 126. The sealing
flange 126 includes a heat resistant layer 128 formed on the back
surface 130. A releasable sealant 132 is formed on the opposite
surface 133 of the sealing flange 126. The zipper closure shown in
FIG. 14 is configured to allow product to be filled through the
zipper and into the open interior of the package.
[0090] FIG. 14b illustrates the same zipper closure as shown in
FIG. 14a except installed in an alternate manner. As illustrated in
FIG. 14b, the male and female closure profiles 28, 30 are initially
engaged with each other and the female closure profile attached to
the side panel 12 through the application of either heat or the use
of an adhesive. In this condition, product can be inserted into the
open interior 16 of the package through the opening 95 between the
back face surface 135 of the male profile element 28 and the side
panel 14. As illustrated, the back surface 135 of the male closure
profile 28 includes lines of adhesive 134. The lines of adhesive
134 bond with the side panel 14 through the application of heat to
adhere the zipper closure across the open mount of the reclosable
package.
[0091] As illustrated in FIG. 14c, the releasable sealant 132
attaches to the side panel 12 while the layer of heat resistant
material 130 prevents attachment of the sealing flange 126 to the
side panel 14.
[0092] Upon opening the reclosable package 10 for the first time,
the sealing flange 126 separates from the side panel 12 along the
releasable sealant 132. Alternatively, the sealing flange 126 can
include a line of weakness such that the sealing flange 126
separates from the remaining portion of the male closure profile 28
during the initial opening.
[0093] FIGS. 15a-15c illustrate yet another embodiment of the
zipper closure 26. In the embodiment shown in FIG. 15a, the male
closure profile 28 includes a depending sealing flange 136. The
sealing flange 136 is separated from remaining portions of the male
closure profile 28 by a line of weakness 138, as shown in FIG. 15b.
Referring back to FIG. 15a, the sealing flange 136 includes
multiple ribs 140 formed from a permanent sealant. The ribs 140
form a bond with the side panel 12 when the package 10 is closed,
as shown in FIG. 15b.
[0094] Referring back to FIG. 15a, the opposite face surface of the
sealing flange includes a series of ribs 142 formed from a
non-sealing material. The ribs 142 prevent the sealing flange 136
from becoming attached to the side panel 14 when the reclosable
package 10 is closed, as shown in FIG. 15b.
[0095] When the package 10 is initially opened, the sealing flange
136 separates from the remaining portions of the male closure
profile 28 along the line of weakness 138. Thus, when the package
is initially opened, the sealing flange 136 remains attached to the
side panel 12 as illustrated in FIG. 15c.
[0096] As can be understood by the description of the alternate
embodiments shown in FIGS. 1-15, the zipper closure positioned
along the open mouth of the reclosable package allows the opposite
side panels to be mated together to close the package. Each of the
alternate embodiments illustrated includes a sealing flange or
similar element that extends across the open interior of the
reclosable package to prevent product from migrating into contact
with the closure elements of the mating male and female closure
profiles 28, 30. In each embodiment of the invention, the male and
female closure profiles are formed from a polypropylene material
that is bonded to the polypropylene side panels 12 and 14. The
materials used to form the zipper closure and side panels can
withstand the temperatures associated with the retort process, as
clearly described above. The embodiments illustrated in FIGS. 1-15
allow for top filling of the package either through the closure
profiles or past the closure profiles, as described. Once the
product package is filled, the top edge of the package is sealed to
create a package that can withstand the retort process.
[0097] Referring now to FIG. 16a, thereshown is another alternate
embodiment of the zipper closure, as referred to by reference
numeral 70. The zipper closure 70 includes a male closure profile
72 and a female closure profile 74. The male and female closure
profiles 72 and 74 each include an attachment flange 76 that is
joined to the respective side panel 12, 14 of the reclosable
package in the manner previously described.
[0098] Referring now to FIG. 16b, both of the male and female
closure profiles 72 and 74 are joined to each other by connecting
flanges 78 and 80. The connecting flanges 78 and 80 are joined to
each other along a line of weakness, such as a folded die line 82
that defines a weakened portion of the zipper closure 70.
[0099] As illustrated in FIG. 16a, the reclosable package has an
open bottom end 84 through which product can be bottom filled into
the reclosable package 10. The interconnection of the connector
flanges 78 and 80, as well as the attachment of the male and female
closure profiles 72, 74 to the side panels 12 and 14, provides a
hermetic seal at the top of the package 10 below the male and
female closure posts.
[0100] Referring now to FIG. 17, product 50 can be inserted into
the package 10 through the open bottom end 84. After the product 50
has been inserted into the package, the side panels 12 and 14 are
heat sealed to each other along a sealing joint 86 (FIG. 18) to
define the package. Once the bottom end 84 has been sealed along
the joint 86, the package is subjected to the retort procedure,
inverted and shipped to a consumer.
[0101] Upon receipt, the consumer can grasp the top tear off header
88 which is separated from the side panels 12 and 14 along a pair
of lines of perforation 90 and 92 shown in FIG. 18. Upon grasping
the top tear off header 88, the user can remove the top tear off
header 88 as illustrated in FIG. 19.
[0102] Once the top tear off header 88 has been removed, the user
can grasp the gripping strips 60 formed on the male closure profile
72 and the female closure profile 74 and pull the profiles 72, 74
apart until the male closure post 32 separates from the pair of
female closure posts 36 and 38, as illustrated in FIG. 20. As
illustrated in FIG. 20, the die line 82 between the connecting
flanges 78 and 80 provides a seal upon the initial separation of
the interlocking profiles.
[0103] As with the first embodiment of the invention previously
described, the connection between the flanges 78 and 80 prior to
product being inserted into the package and subjected to the retort
procedure prevents the product from migrating through the
interlocking members of the zipper closure. Thus, upon initial
opening of the package, the user can grasp the male closure profile
72 and the female closure profile 74 without any product being
present.
[0104] As illustrated in FIG. 21, if the user further pulls the
male and female closure profiles 72 and 74 apart, the connecting
flanges 78 and 80 separate to provide access to the product 50
contained within the reclosable package. In this manner, the male
and female closure profiles 72, 74 provide not only a seal to
prevent product migration past the zipper closure, but also provide
a tamper evident feature to the reclosable package.
[0105] FIG. 22 illustrates an alternate embodiment of the zipper
closure 70 for a bottom filled package. In the embodiment shown in
FIG. 22, the male closure profile 72 and the female closure profile
74 are joined to each other by a membrane 144. The membrane 144
includes a first end 146 coupled to the male closure profile 72 and
a second end 148 coupled to the female closure profile 74. In the
preferred embodiment of the invention, the membrane 144 has a
material strength less than the strength of the bond between the
male and female closure profiles 72, 74 and the side panels 12, 14.
Thus, during the initial opening of the reclosable package 10, the
membrane 144 tears or ruptures to provide access to the open
interior of the reclosable package 10.
[0106] In one contemplated embodiment of the invention, the first
and second ends 146, 148 of the membrane 144 are adhesively
attached to the male and female closure profiles 72, 74. However,
it is contemplated that the membrane 144 could be co-extruded with
the male and female closure profile elements 72 and 74. In either
case, the bond between the first and second ends 146, 148 of the
membrane 144 to the male and female closure profiles 72, 74 must be
greater than the material strength of the membrane 144 such that
the membrane 144 tears upon initial opening of the product package.
Additionally, the membrane 144 must be selected such that it is
impermeable to the product contained within the reclosable package
10 to prevent the product from migrating into contact with the
closure elements of the zipper closure.
[0107] FIG. 23 illustrates yet another embodiment of the zipper
closure 70 particularly useful with a bottom-fill reclosable
package 10. In the embodiment shown in FIG. 23, the male and female
closure profiles 72, 74 each include a depending attachment flange
150, 152. The attachment flanges each include a releasable sealant
154, 156 such that the attachment flanges 150, 152 can be joined to
each other along the releasable sealants 154, 146. During initial
opening of the product package, the attachment flanges 150, 152
separate from each other through the separation of the releasable
sealant layers 154, 156. Preferably, the releasable sealant 154,
156 is an FDA approved sealant.
[0108] FIG. 24 illustrates yet another alternate embodiment of the
zipper closure 70 for use with a bottom-fill reclosable package. In
the embodiment illustrated in FIG. 24, the male closure profile 72
includes an extended sealing flange 154 that extends across the
open interior of the package from the side panel 12 to the side
panel 14. The sealing flange 154 includes a releasable adhesive 156
that holds the sealing flange 154 in contact with the side panel
14.
[0109] During initial opening of the package, the sealing flange
154 separates from the side panel 14 along the releasable adhesive
156. In the preferred embodiment of the invention, the releasable
adhesive 156 is an FDA approved sealant.
[0110] FIG. 25 illustrates another alternate embodiment for the
zipper closure 70 for use with a bottom-fill reclosable package. As
illustrated in FIG. 25, a membrane 158 extends across the open
package interior from the male closure profile 72 to the side panel
14. The male closure profile 72 includes an extended attachment
flange 160. The extended attachment flange 160 receives a first end
162 of the membrane 158. Preferably, the membrane 158 can be
attached to the extended attachment flange 160 through either a
layer of adhesive or through a co-extrusion process. The second end
164 of the membrane 158 includes a releasable sealant 166 that
allows the membrane 158 to be removably attached to the side panel
14.
[0111] During initial opening of the package 10 shown in FIG. 25,
the bond between the releasable adhesive 166 and the side panel 14
is destroyed to provide access to the open interior of the package.
As can be understood, the bond between the first end 162 of the
membrane 158 and the attachment flange 160 is greater than the
strength of the sealant 166 such that the opening interior of the
product package can be accessed.
[0112] FIG. 26 illustrates yet another embodiment of the invention.
The embodiment illustrated in FIG. 26 is similar to the embodiment
illustrated in FIG. 24 and includes a sealing flange 154 that
extends from the male closure profile 72. However, in the
embodiment illustrated in FIG. 26, the sealing flange 154 includes
a line of weakness 168. Additionally, the end 170 of the sealing
flange 154 is attached to the side panel 14 by a permanent sealant
172, rather than the releasable sealant 156 shown in FIG. 24.
[0113] During initial opening of the product package 10, including
the zipper closure 70 shown in FIG. 26, the sealing flange 154
fractures along the line of weakness 168. The separation along the
line of weakness 168 allows for access to the open interior of the
product package 10 including the zipper closure 70 shown in FIG.
26. The permanent sealant 172 shown in FIG. 26 is preferably the
same sealant shown and described in the first embodiment of the
invention shown in Figure la.
[0114] FIG. 27 illustrates yet another embodiment of the zipper
closure 70 for use with a bottom-fill reclosable package 10. In the
embodiment of the invention illustrated, the male closure profile
and the female closure profile 74 are joined to each other along a
curved, center section 174. The center section 174 includes a line
of weakness 176 positioned somewhere along its length. The line of
weakness 176 can be formed either during the extrusion process, or
as a weakened area during subsequent processing of the zipper
closure 70. When the reclosable package 10 is initially opened, the
male closure profile 72 separates from the female closure profile
along the line of weakness 176.
[0115] Referring now to FIG. 28, thereshown is yet another
embodiment of the zipper closure 70 of the present invention for a
bottom-fill reclosable package. In the embodiment shown in FIG. 28,
a first sealant strip is formed on the side panel 12 and a second
sealant strip 180 is formed on the opposite side panel 14. Prior to
filling of the package 10, the sealant strips 178 and 180 are
brought into contact with each other, as shown. The interaction
between the sealant strips 178 and 180 prevents product from
migrating into contact with the closure elements formed on the male
closure profile 72 and the female closure profile 74.
[0116] Once the product has been filled into the reclosable package
and subjected to the retort process, the package can be stored.
Upon initial opening, the male and female closure profile elements
72, 74 are separated. Further separation results in the separation
of the sealant strips 178, 180 to provide access to the open
interior 16 of the package 10. In the preferred embodiment of the
invention, the sealant strips 178, 180 are formed from a releasable
sealant.
[0117] In the embodiments of the invention illustrated in FIGS.
16-28, the male and female closure profiles 72 and 74 are formed
from the same material as the closure profiles described above in
reference to the top filled package and zipper designs shown in
FIGS. 1-15. Thus, the bottom filled reclosable packages illustrated
in FIGS. 16-28 can be subjected to the retort procedure without
negatively affecting the performance of the male and female closure
profiles.
[0118] Having described the presently preferred embodiments, it is
to be understood that the invention may be otherwise embodied
within the scope of the appended claims.
* * * * *