WO2001046028A1

WO2001046028A1 - Reclosable packages with barrier properties

Info

Publication number: WO2001046028A1
Application number: PCT/US2000/032339
Authority: WO
Inventors: David V. Dobreski; Steve P. Long; Toby R. Thomas
Original assignee: Pactiv Corporation
Priority date: 1999-12-21
Filing date: 2000-11-27
Publication date: 2001-06-28
Also published as: CA2394607A1; AU1802301A; US20020131653A1; EP1250267A4; CA2394607C; US20020097923A1; EP1250267A1; US6499878B1; JP2003517975A

Abstract

A reclosable package (10) includes a pair of opposing walls (16, 18), a reclosable seal (14) and a barrier partition (12). The opposing walls are joined along a pair of opposing sides, and a bottom bridges the opposing sides to create a receptacle space having a mouth end opposite the bottom. The reclosable seal extends along the mouth end and includes first and second opposing reclosable elements (26, 32). The first and second reclosable elements are releasably engageable to each other. The barrier partition comprises at least a first layer that is substantially impermeable to at least one of oxygen, nitrogen and carbon dioxide. The barrier partition extends substantially across the pair of opposing wall panels in the receptacle space.

Description

RECLOSABLE PACKAGES WITH BARRIER PROPERTIES

FIELD OF INVENTION

The present invention relates generally to reclosable packages with barrier properties More particularly, the present invention relates to the use of particular materials as partitions that are substantially impermeable to at least one of oxygen, nitrogen and carbon dioxide

BACKGROUND OF THE INVENTION

Reclosable packages or bags are very common, especially in the food industry- Such packages are typically made to be reclosable via the use of a reclosable element or fastener such as a resealable adhesive seal or a reclosable zipper Such zippers may be opened and closed either by pressure or by the use of an auxiliary slider mechanism

Reclosable packages are a great convenience to consumers, especially for products such as luncheon meats and cheeses where, typically, only a portion of the product is used at any given time One problem with these reclosable packages, however, is that the packages are not substantially impermeable to various gases such as oxygen, nitrogen and carbon dioxide These gases may enter into the packages from the external atmosphere causing food spoilage

One attempt to address this problem has involved encapsulating the reclosable feature by extending the wall panels of the package One disadvantage of this type of package is that the extended wall panels may interfere with the operation of opening and closing the package, resulting in customer dissatisfaction Another disadvantage includes higher product costs involved with using additional resins for extending the wall panels This type of package also involves an additional step for the customer of removing a tear strip or manually cutting the wall panels to gain access to the package A need therefore exists for packages or bags being substantially impermeable to gases such as oxygen, nitrogen and carbon without having the above-noted disadvantages

SUMMARY OF THE INVENTION

According to one embodiment of the present invention, a reclosable package includes a pair of opposing walls, a reclosable seal and a barrier partition The pair of opposing wall panels are joined along a pair of opposing sides and a bottom bridges the opposing sides to create a receptacle space having a mouth end opposite the bottom The reclosable seal extends along the mouth end and includes first and second opposing reclosable elements The first and second reclosable elements are releasably engageable to each other The barrier partition comprises at least a first layer that is substantially impermeable to at least one of oxygen, nitrogen and carbon dioxide The barrier partition extends substantially across the pair of opposing wall panels in the receptacle space

According to another embodiment, a reclosable package includes a pair of opposing walls, a reclosable seal and a barrier partition The reclosable seal extends along the mouth end and includes first and second opposing tracks The first and second tracks include respective first and second profiles The first and second opposing tracks are releasably engageable to each other The first and second tracks are connected to the respective opposing wall panels The first and second profiles include at least a first layer that is substantially impermeable to at least one of oxygen, nitrogen and carbon dioxide The barrier means are proximate to upper edges of the respective first and second profiles The barrier means are substantially impermeable to at least one of oxygen, nitrogen and carbon dioxide

According to another embodiment, a reclosable package includes a barrier partition comprising at least a first layer that includes a material selected from the group consisting of vinyl alcohol, polyvinyl alcohol, nylon, polyester, ethylene vinyl dichloride, liquid crystal polymer, polyvinyl chloride, polyvinylidene chloride, modified polyolefins with barrier properties, polyacrylonitrile, acrylonitriles copolymers, polyacetal, cellophane or combinations thereof

According to a further embodiment, a fastener of the present invention includes first and second opposing elements, a first fin portion and a second fin portion The first and second opposing reclosable elements are releasably engageable to each other The first fin portion extends downward from the first reclosable element The first fin portion comprises at least a first layer that is substantially impermeable to at least one of oxygen, nitrogen and carbon dioxide The second fin portion extends downward from the second reclosable element The second fin portion comprises at least a first layer that is substantially impermeable to at least one of oxygen, nitrogen and carbon dioxide The second fin portion and the first fin portion are joined to each other According to a yet another embodiment, a fastener of the present invention includes first and second opposing tracks that are releasably engageable to each other The first and second opposing tracks have a first and second profile, respectively The first and second profiles comprise at least a first layer that is substantially impermeable to at least one of oxygen, nitrogen and carbon dioxide

According to one process of the present invention, a coating is applied to a reclosable bag The provided reclosable bag comprises a pair of opposing wall panels joined along a pair of opposing sides and a bottom bridging the opposing sides to create a receptacle space having a mouth end opposite the bottom A reclosable seal extends along the mouth end and includes first and second opposing tracks The first and second tracks include respective first and second profiles The first and second opposing tracks are releasably engageable to each other The first and second tracks are connected to the respective opposing wall panels The process also includes applying a coating to at least a portion of the first and second tracks The coating includes at least a first layer that is substantially impermeable to at least one of oxygen, nitrogen and carbon dioxide

BRIEF DESCRIPTION OF THE DRAWINGS

Other objects and advantages of the invention will become apparent upon reading the following detailed description and upon reference to the drawings

FIG 1 is a section view of a mouth portion of a reclosable package or bag having fin portions joined below a fastener according to one embodiment of the present invention,

FIG 2 is a perspective view of the reclosable package incorporating the mouth portion depicted in FIG 1 in which a reclosable zipper has a slider mechanism being opened and the fin portions being partially opened, FIG 3 is a section view of a mouth portion of a reclosable portion having fin portions comprising two layers according to one embodiment of the present invention,

FIG 4 is a section view of a mouth portion of a reclosable portion having fin portions comprising three layers according to a further embodiment of the present invention. FIG 5 is a section \iew of a mouth portion of a reclosable portion having fin portions comprising four layers according to another embodiment of the present invention,

FIG 6 is a section view of a mouth portion of a reclosable portion having fin portions comprising five layers according to yet another embodiment of the present invention,

FIG 7 is a section view of a mouth portion of a reclosable package having a barrier partition formed by integral extensions of opposing wall panels located below a fastener, FIG 8 is a perspective view of a reclosable package according to one embodiment of the present invention, showing the package in sealed form having upstanding fins in the process of being broken,

FIG 9 is an enlarged section view taken generally along line 9-9 of FIG 8,

FIG 10 is a perspective view of the reclosable bag, showing the bag in partially opened form after the upstanding fins have been completely broken,

FIG 1 1 is an enlarged section view of zipper profiles and upstanding fins comprising two layers according to one embodiment of the present invention,

FIG 12 is an enlarged section view of zipper profiles and upstanding fins comprising three layers according to one embodiment of the present invention, FIG 13 is an enlarged section view employing a continuous bead of adhesive to connect the zipper profiles,

FIG 14 is an enlarged section view similar to that of FIG 13 but integrally forming the zipper profiles to connect them to each other,

FIG 15 is a section view of the zipper profiles as extruded with each other end-to- end to achieve the integral connection shown in FIG 14

While the invention is susceptible to various modifications and alternative forms, specific embodiments thereof have been shown by way of example in the drawing and will herein be described in detail It should be understood, however, that it is not intended to limit the invention to the particular forms disclosed but, on the contrary, the intention is to cover all modifications, equivalents, and alternatives falling within the spirit and scope of the invention as defined by the appended claims DESCRIPTION OF ILLUSTRATIVE EMBODIMENTS

Turning now to the drawings, FIG 1 depicts a mouth portion of a reclosable package or bag 10 having a barrier partition 12 located below a fastener or zipper 14

The barrier partition 12 of FIG. 1 is also tamper-evident FIG 2 shows the reclosable package 10 opening the mouth portion depicted in FIG 1

Referring to FIGS 1 and 2, the mouth portion of the reclosable package 10 includes a pair of opposing wall panels 16 and 18 that make up a package body 20 and define a receptacle space 22 Connected to the wall panel 16 is a first track 24 having a first profile 26 and a first fin portion 28 extending downward from the first profile 26 Connected to the other wall panel 18 is a second track 30 having a second profile 32 and a second fin portion 34 extending downward from the second profile 32 The first and second profiles 26 and 32 are releasably engageable with each other to provide a reclosable seal to the package 10

The barrier partition 12 comprises at least a first layer that is substantially impermeable to at least one of oxygen, nitrogen and carbon dioxide As shown in FIG 1, the barrier partition 12 extends across the pair of opposing wall panels 16 and 18 in the receptacle space 22 The barrier partitions of the present invention are preferably substantially impermeable to oxygen, nitrogen and carbon dioxide

The first layer of the barrier partition 12 may comprise ethylene vinyl alcohols (EVOH), polyvinyl alcohols (PVOH), nylons, polyesters, ethylene vinyl dichlorides (EVDC), liquid crystal polymers (LCPs), polyvinyl chloride (PVC), polyvinylidene chloride (PVDC), modified polyolefins with barrier properties, polyacrylonitriles, acrylonitrile copolymers, polyacetals, cellophanes or combinations thereof The first layer of the barrier partition 12 is preferably made of an EVOH, PVDC, nylon or polyester Preferred nylons include nylon-6, nylon-66, nylon-MXD6 and amorphous nylons Preferred polyesters include polyethylene terephthlate (PET) and polybutylene terephthlate (PBT) It is preferred that water soluble materials, such as PVOH, do not comprise the first layer if the barrier partition is made of only the first layer because those materials may dissolve in a moisture environment or lose strength and/or barrier characteristics

The first layer generally has an oxygen transmission rate (OTR) less than 100 cm³ (miiyiOO in² (d) (atm) at 23°C as measured by ASTM D3985-81 The first layer preferably has an oxygen transmission rate less than 20 cm³ (mil)/100 in² (d) (atm) at

23 °C and, more preferably, less than 10 cm³ (mil)/ 100 in² (d) (atm) at 23 °C as measured by ASTM D3985-81

The first layer of the barrier partition 12 may also be substantially impermeable to water vapor and other gases causing dehydration, increased humidification and/or oxidation The first layer of the barrier partition 12 preferably assists in inhibiting loss of flavor, absorption of external odors and development of microflora (bacteria) in the food products of the package 10

It is contemplated that oxygen absorbers/scavengers may be included in the formation of the first layer of the barrier partition 12 Oxygen absorbers or scavengers are generally chemical or enzyme based Chemical oxygen scavengers contemplated in the present invention include metallic reducing agents such as various ferrous compounds, powdered iron oxide and metallic platinum Other chemical oxygen scavengers include non-metallic formulations such as those employing ascorbic acids (Vitamin C) and their associated salts and organo-metallic molecules that have a natural affinity for oxygen It is contemplated that additional materials may be added in forming the barrier partition 12 These materials include various fillers, such as clay, talc, mica and nanocomposites that may be more cost effective These fillers may provide a tortuous path for oxygen, nitrogen or carbon dioxide Similarly, the opposing wall panels 16 and 18 are also made of at least one layer that is substantially impermeable to at least one of oxygen, nitrogen and carbon dioxide and, preferably, substantially impermeable to all of the above The first layer of the opposing wall panels 16 and 18 may be made of similar material as described above in forming the first layer of the barrier partition 12 The opposing wall panels 16 and 18 may be made from multiple layers The first layer of the opposing wall panels 16 and 18 may be located on the inside layer or as an interior layer

One example of an opposing wall panel 16 or 18 is a three layer structure with the first layer comprising polyester and being located as an outside layer of the wall panels, a second layer comprising polyolefin that is located on the interior, and a third layer being a tie layer located between the first and second layers The tie layer may be made from, for example, ethylene vinyl acetate (EVA) or a modified EVA The first layer of the opposing wall panels 16 and 18 may be made of nylon Polyolefins that are typically used in forming the second layer of the opposing wall panels 16 and 18 include polyethylenes and polypropylenes

It is contemplated that various other layered structures may form the opposing wall panels 16 and 18 For example, the opposing wall panels 16 and 18 may have a layer of EVA and a layer of polyester Alternatively, the opposing wall panels 16 and 18 may have an EVA layer and a layer of nylon The layers of each of the opposing wall panels may be joined by coextrusion, extrusion lamination or adhesive lamination It is also contemplated that pigments, metallic components, paper, and/or paper/polymeric compositions may be incorporated into layer(s) forming the opposing wall panels 16 and 18 of the present invention

In the illustrated embodiment of FIG 1, the lower edges of the first and second fin portions 28 and 34 are joined to each other along an optional one-time breakable preferential area of weakness or preferential tear area 38 to form a one-time breakable tamper evident feature The optional preferential area of weakness 38 is substantially impermeable to at least one of oxygen, nitrogen and carbon dioxide and, preferably, substantially impermeable to all of the above It is not necessary that the first and second fin portions 28 and 34 have a one-time breakable preferential area of weakness 38 For example, the first and second fin portions 28 and 34 may be made in a manner such that the fin portions 28 and 34 are separated by cutting the fin portions apart The preferential area of weakness 38 inhibits tampering with the bag 10 prior to being opened The joined first and second fin portions 28 and 34 have a generally U-shaped or V-shaped cross- sectional configuration

To join the first and second fin portions 28 and 34, the first and second fin portions 28 and 34 may be extruded as a single continuous fin having the preferential area of weakness 38 In one embodiment, the preferential area of weakness 38 takes the form of a score line or a thinned line A score line may be created by making a uniform crease at the intersection of the fin portions 28 and 34 Alternatively, a score line may be formed on any portion(s) of the fin portions 28 and 34 A thinned line is created by extruding the fin portions 28 and 34 with less plastic material along the region joining the lower edges of the fin portions 28 and 34 In another embodiment, the preferential area of weakness 38 results from forming the single continuous fin out of a region of highly oriented plastic that has a tendency to split along the preferential area of weakness 38 Instead of extruding the first and second fin portions 28 and 34 as a single continuous fin, the fin portions 28 and 34 may be separately extruded and then later weakly attached at their lov/er edges or some other location by heat sealing, welding, or the like The weak attachment of the first and second fin portions 28 and 34 creates the

5 preferential area of weakness 38

The thicknesses of the first and second fin portions 28 and 34 may vary from generally about 2 to about 10 mil The thicknesses of the first and second fin portions 28 and 34 are typically from about 6 to about 8 mil

The reclosable package 10 may further include an optional auxiliary slider o mechanism 36 (FIG 2) slidably mounted to the zipper 14 for movement between a closed position and an open position The first and second profiles 26 and 32 are engaged to each other while the slider mechanism 36 is in the closed position, and movement of the slider mechanism 36 from the closed position to the open position disengages the profiles 26 and 32 from each other The package 10 of FIG 2 also includes end termination s clamps 37 The end clamps 37 perform the dual function of stops for the ends of the zipper 14 to prevent the slider 36 from going past the zipper 14 and, in addition, the end clamps 37 hold the first and second profiles 26 and 32 together to resist stresses applied to the profiles during normal use of the package 10 The composition and manner of operation of this zipper, slider arrangement and end clamps is described in detail in U.S o Patent No 5,067,208 to Herrington, Jr et. al , which is incorporated herein by reference in its entirety

As illustrated in FIG 2, in order to open the reclosable package 10 of the present invention, a consumer grips the slider mechanism 36 and moves it such that the first and second profiles 26 and 32 of the respective first and second tracks 24 and 30 are detached 5 from each other Next, the consumer tears open the barrier partition 12 along the preferential area of weakness 38 Alternatively, the consumer may open the barrier partition 12 by cutting the first and second fin portions 28 and 34 The package can be resealed utilizing the zipper 14 and slider mechanism 36 Specifically, the consumer grips the slider mechanism 36 and moves it from the open position to the closed position so as o to engage the complementary first and second profiles 26 and 32

As shown in FIGS 3-6, barrier partitions of the present invention may be formed of multiple layers As shown in FIG 3, a barrier partition 40 comprises a first fin portion 42 and a second fin portion 44. Each of the fin portions 42 and 44 comprises a first layer

46 and a second layer 48 The first layer 46 may comprise the same materials as described above in making the first layer of the barrier partition 12 The first layers of the first and second fin portions may be made of different materials The second layer 48 may be connected to the opposing wall panels 16 and 18 as shown in FIG 3 The second layer 48 is a tie layer and may be made from various materials such as ethylene vinyl acetate (EVA), anhydride modified polyolefins, anhydride modified ethylene-acrylates, anhydride modified EVAs, acid modified EVAs, acid modified ethylene-acrylates, amorphous polyolefin-modified EVA polymers or combinations thereof Some examples of anhydride modified polyolefins include anhydride modified high density polyethylene (HDPE), anhydride modified low density polyethylene (LDPE) and anhydride linear low density polyethylene (LLDPE) The second layers of the fin portions may be made of different materials

Referring to FIG 4, a barrier partition 50 is similar to the barrier partition 40 of FIG 3 except that it further includes a third layer 51 in both of the first and second fin portions 52 and 54 The third layer 51 of FIG 4 is a tie layer and may be made of similar materials as described above with respect to the second layer 48 The third layer 51 is located on the interior of the barrier partition 50, such that the first layer 46 is located between the second layer 48 and the third layer 51 Other barrier partitions having three layers are contemplated For example, a barrier partition (not shown) may include a first layer having the same materials as described above in making the first layer of the barrier partition 12, a tie layer and a third layer made of polyolefin(s), such as an LDPE, an HDPE, an LLDPE or a combination thereof In this embodiment, the first layer would be preferably located on the interior of the barrier partition with the tie layer being located between the first and third layers

The barrier partitions of the present invention may include four layer and five layer fin portions such as shown in barrier partition 60 (see FIG 5) and in barrier partition 70 (see FIG 6) Referring first to FIG 5, the barrier partition 60 further includes a fourth layer 61 in both of the first and second fin portions 62 and 64 The fourth layer 61 of FIG 5 may be made of polyolefin(s), such as an LDPE, an HDPE, an LLDPE or a combination thereof As shown in FIG. 5, the fourth layer 61 is located on the interior of the barrier partition 60 and is adjacent to the third layer 51

Other four layered fin portions are contemplated in the present invention For example, a four layer structure (not shown) may include two first layers substantially impermeable to at least one of oxygen, nitrogen and carbon dioxide, a tie layer and a polyolefinic layer The two first layers may be made with materials that are independently selected from each other, such as described above in the first layer of the barrier partition 12 In this embodiment, the polyolefinic layer may be located as an exterior layer with the tie layer located adjacent to the polyolefinic layer The remaining layers are located adjacent to each other with one of the layers being located on an interior layer of the barrier partition

Referring to FIG 6, a barrier partition 70 further includes a fifth layer 71 in both of its first and second fin portions 72 and 74 The fifth layer 71 of FIG 6 may be made of the same materials (polyolefins) as described above with respect to the fourth layer 61 It is also contemplated that additional layers may be added in forming the first and second fin portions of the present invention For example, six or seven or more layered first and second fin portions are contemplated in the present invention

In one preferred three layer fin portion, the first layer 46 is EVOH, the second layer 48 is a tie layer and the third layer 51 is a tie layer. In another preferred three layer fin portion, the first layer 46 is nylon, the second layer 48 is a tie layer and the third layer 51 is a tie layer In one preferred four layer fin portion, the first layer 46 is EVOH, the second layer 48 is a tie layer, the third layer 51 is a tie layer and the fourth layer 61 is LDPE In another preferred four layer fin portion, the first layer 46 is nylon, the second layer 48 is a tie layer, the third layer 51 is a tie layer and the fourth layer 61 is LDPE In one preferred five layer fin portion, the first layer 46 is EVOH, the second layer

48 is a tie layer, the third layer 51 is a tie layer, and the fourth and fifth layers 61 and 71, respectively, are independently selected polyolefins, such as LDPE, HDPE or LLDPE In another preferred five layer fin portion, the first layer 46 is nylon, the second layer 48 is a tie layer, the third layer 51 is a tie layer, and the fourth and fifth layers 61 and 71, respectively, are independently selected polyolefins, such as LDPE, HDPE or LLDPE The first and second fin portions, such as shown in FIGS 3-6, may be formed by coextruding the multiple layers that form each fin portion The first and second fin portions may also be formed by other processes such as coating or laminating

In an alternative embodiment depicted in FIG 7, a mouth portion 90 includes wall panel portions 92 and 94, first and second tracks 96 and 98, and first and second profiles 100 and 102 The first and second tracks 96 and 98 are coextruded with the respective wall panels 92 and 94 The mouth portion also includes a barrier partition 104 that is formed by integral extensions of the wall panel portions 92 and 94 Alternatively, a barrier partition may be formed by an integral extension of only one of the wall panel portions 92 and 94 (not shown) The barrier partition 104 of FIG 7 is also tamper resistant The barrier portion 104 may include an optional one-time breakable preferential area of weakness 106, such as shown in FIG 7

By being substantially impermeable to at least oxygen, nitrogen and/or carbon dioxide, the barrier partitions of the present invention assist in preserving the freshness of the food contents of the package prior to its initial opening Since the fastener is located above the barrier partitions, the operation of the fastener is not hampered by the presence of a barrier partition The barrier partition of the present invention also provides a consumer with the assurance that the newly purchased package has not been opened The optional slider mechanism 36 is optimally made from polypropylenes, copolymers of polyethylene and polypropylene, polycarbonates or polyesters Especially preferred components for making the slider mechanism 36 are polypropylenes, polycarbonates or polyesters

The components of the fastener such as the tracks having integrally formed interlocking profiles and fin portions may be attached to the wall panels of the package by processes such as heat sealing, welding or blocking The process utilized depends upon the materials from which the bag and the fastener are made Specifically, heat sealing is a process whereby materials are fused or melted together Welding is a process where an intermediate third material is utilized to "glue" similar materials to each other Blocking is a process where at least sufficient pressure and optional temperature increases result in intimate surface contact adhesion of layers without sealing

Alternatively, an adhesive seal may be utilized as a fastener or reclosable element of the present invention Such seals employ a resealable adhesive-type substance that is applied to either one or bo h of the films making up the package The adhesive may alternatively be applied to an intermediary base strip It is contemplated that other fasteners, besides adhesive seals and zippers, may be used in the present invention

Referring to FIGS 8-10, a reclosable package or bag 110 is shown according to another embodiment of the present invention The reclosable package 110 includes a fastener or zipper 1 14 extending along a mouth formed opposite of a sealed bottom The package 1 10 comprises first and second opposing panels 1 16 and 1 18 that make up a package body 120 and define a receptacle space 122 Connected to the wall panel 116 is a first track 124 having a first profile 126 and a first fin portion 128 extending downward from the first profile 126 Connected to the other wall panel 118 is a second track 130 having a second profile 132 and a second fin portion 134 extending downward from the second profile 132 The first and second profiles 126 and 132 are releasably engageable with each other to provide a reclosable seal to the package 110

Referring still to FIGS 8-10, the package 1 10 further has an optional auxiliary slider mechanism 136 and end clamps 137 that function as described above in the slider mechanism 36 and the end clamps 37 of FIGS 1 and 2

To inhibit tampering with the contents of the package 110 prior to being initially opened, the slider 136 is initially parked in the closed position at one end of the zipper 1 14 as depicted in FIG 8 Moreover, upper edges of the first and second profiles 126 and 132 are detachably connected to each other, except at one end of the zipper 1 14 supporting the parked slider 136, such that the slider 136 cannot be moved from the closed position until the barrier feature is broken

As shown in FIGS 8 and 9, the package 1 10 is provided with first and second upstanding fins or flanges 139 and 141 that extend upward from the respective first and second profiles 126 and 132 The first and second upstanding fins 139 and 141 are detachably connected to their respective first and second profiles 126 and 132 along a preferential area of weakness 143 and are fused to each other so as to effectively connect the upper edges of the first and second profiles 126 and 132

The preferential area of weakness 143 may be in the form of a scored line, a thinned line or highly orientated material The first and second upstanding fins 139 and 141 extend substantially across the bag mouth, with the exception that the fins 139 and 141 do not occupy the end portion of the zipper 1 14 supporting the slider 136 while the slider 136 is in the closed position If a slider is not used, the first and second upstanding fins 139 and 141 may extend across the entire bag mouth Alternatively, the first and second upstanding fins 139 and 141 may be removed by cutting the upstanding fins from a remainder of the package 110 The slider 136 is retained in the closed position by the ends of the first and second upstanding fins 139 and 141, thereby preventing access via the bag mouth to the interior of the package 1 10 The slider 136 cannot be moved from the closed position until the first and second upstanding fins 139 and 141 are detached from the first and second profiles 126 and 132 along the preferential area of weakness 143 To remove the first and second upstanding fins 139 and 141, a consumer first grasps the upstanding fins at one end of the bag mouth as shown in FIG 8 and then pulls the upstanding fins in an upward direction away from the zipper 1 14 The pulling force causes the package 1 10 to tear along the preferential area of weakness 143 Once the first and second upstanding fins 139 and 141 are removed, the connection of the upper edges of the first and second profiles 126 and 132 is broken (because the first and second profiles 126 and 132 are not connected below the preferential area of weakness 143) This allows the slider 136 to be moved to the open position to gain access to the interior of the package 1 10 FIG 10 depicts the slider 136 in the process of being moved toward the open position

The first and second upstanding fins 139 and 141 include a first layer that is substantially impermeable to at least one of oxygen, nitrogen and carbon dioxide and, preferably, to oxygen, nitrogen and carbon dioxide The first and second upstanding fins 139 and 141 may also be formed of multiple layers as discussed above with respect to the fin portions 28 and 34 For example, as shown in FIG 1 1 , the first and second upstanding fins 139 and 141 include two layers The first layers 139a and 141a may comprise a material that is independently selected from the materials made in forming the first layer of the barrier partition 12 described above Layers 139b and 141b may be made of independently selected tie layers as described above, for example, in forming the second layer 48 depicted in FIG 4

Another embodiment of the first and second upstanding fins 139 and 141 is depicted in FIG 12 Each of the first and second upstanding fins 139 and 141 of FIG 12 has three layers Layers 139a, 139b, 141a and 141b are the same as described above in FIG 1 1 Layers 139c and 141c comprise independently selected polyolefins, including the polyolefins described above in forming the fourth layer 61 depicted in FIG 5

Prior to being removed, the first and second upstanding fins 139 and 141 also restrict access to the contents of the package 1 10 If a consumer purchases a prepackaged package 1 10 with the upstanding fins 139 and 141 intact, it is not likely that the contents of the package 110 have been tampered with because the slider 136 cannot be moved and the bag mouth cannot be opened without first tearing off the upstanding fins 139 and 141 If, on the other hand, the consumer purchases a package 1 10 with part or all of the fins 139 and 141 detached from the zipper 114 along the preferential area of weakness 143, then it is more likely that the contents of the package 1 10 have been tampered with Thus, the upstanding fins 139 and 141 also provide an effective tamper- evident feature for the package 110

The first and second profiles 126 and 132, as shown, for example, in FIGS 1 1 and 12 may have multiple layers In FIG 11, the first and second profiles 126 and 132 have respective layers 126a and 132a comprised of a material that is independently selected from the materials made in forming the first layer of the barrier partition 12 described above Layers 126b and 132b of the first and second profiles 126 and 132, respectively, may be made of independently selected tie layers as described above, for example, in forming the second layer 48 depicted in FIG 4 In FIG 12, layers 126c and 132c of the first and second profiles 126 and 132, respectively, comprise independently selected polyolefins, including the polyolefins described above in forming the fourth layer 61 depicted in FIG 5

The first and second profiles 126 and 132 may be coated or laminated with a material that is substantially impermeable to at least one of oxygen, nitrogen or carbon dioxide This coating or lamination may comprise the materials described above in forming the first layer of the barrier partition 12

It is contemplated that additional materials may be added in forming the first and second profiles 126 and 132 These materials include various fillers, such as clay, talc, mica and nanocomposites which may be more cost effective These fillers may provide a tortuous path for oxygen, nitrogen or carbon dioxide These materials may be blended with other materials in the formation of the first and second profiles 126 and 132 These materials may be added in a sufficient amount so that the first and second profiles 126 and 132 are substantially impermeable to at least one of oxygen, nitrogen or carbon dioxide

Referring to FIGS. 13-15, reclosable packages 155 and 165, respectively, employ a barrier feature in accordance with the present invention. Elements of the reclosable packages 155 and 165 in FIGS 13 and 14, respectively, correspond to elements of the package 1 10 in FIG 8 and are designated by the same reference numerals The reclosable packages 155 and 165 are similar to the package 1 10 with the exception that the upper edges of the first and second profiles 126 and 132 are directly connected to each other along a line of connection without the use of the upstanding fins 139 and 141 of FIGS 8- 10

As shown in FIGS 13-15, barrier features proximate to the upper edges of profiles may be accomplished in several ways In FIG 13, a continuous bead of adhesive 157 is applied across the upper edges of the profiles 126 and 132 Alternatively, the upper edges of the profiles may be continuously sealed to each other by thermal fusion In another embodiment shown in FIG 14, an upper edge of the first profile 126 is integrally formed with an upper edge of the second profile 132 To achieve this integral connection, the first and second profiles 126 and 132 may be extruded as one piece as shown in FIG 15 and then folded into an interlocking relationship

The continuous bead of adhesive 157 (see FIG 13) is comprised of an adhesive that is substantially impermeable to at least oxygen, nitrogen or carbon dioxide The continuous bead of adhesive 157 preferably is substantially impermeable to oxygen, nitrogen and carbon dioxide The impermeability of the adhesive 157 increases when the cross-sectional thickness of the adhesive is increased The continuous bead of adhesive 157 may be made from hot melt adhesives such as linear saturated polyesters or polyimides, reactive thermosetting adhesives, polyester and polyurethane solutions, solvent and water based adhesives, thermosetting nitrile phenolics, and liquid crystal polymers

Like the upstanding fins 139 and 141 in FIGS 8-10, the continuous line of connection of the upper profile edges in FIGS 13 and 14 extends substantially across the bag mouth If a slider is used, the line of connection does not occupy the end portion of the zipper 114 supporting the slider 136 while the slider 136 is in a closed position The movement of the slider 136 from the closed position will break the line of connection formed by, for example, the continuous bead of adhesive 157 of FIG 13 The slider 136 includes a pointed separator finger (not shown) located between the first and second profiles 126 and 132. As the slider 136 is moved from the closed position to the open position, the separator finger of the slider 136 simultaneously disengages the first and second profiles 126 and 132 from each other and breaks the line of connection along the upper edges of the profiles

In addition to being a substantially impermeable barrier, the line of connection along the upper profile edges serves as an effective tamper-evident feature because the line of connection restricts access to the contents of the packages 155 and 165 If a consumer purchases a prepackaged package 155 or 165 with the line of connection intact, it is less likely that the contents of the package 155 or 165 have been tampered with

The packages 155 and 165 of FIGS 13 and 14, respectively, may have first and second fin portions 128 and 134 made by the same materials as described above in forming the first and second fin portions 26 and 34 The fin portions 128 and 134 may be formed from multi-layers The packages 155 and 165 of FIGS 13 and 14, respectively, have first and second profiles 126 and 132 made of a first layer substantially impermeable to at least one of oxygen, nitrogen or carbon dioxide The first and second profiles 126 and 132 may be formed from multi-layers

While the present invention has been described with reference to one or more particular embodiments, those skilled in the art will recognize that many changes may be made thereto without departing from the spirit and scope of the present invention Each of these embodiments and obvious variations thereof is contemplated as falling within the spirit and scope of the claimed invention, which is set forth in the following claims

Claims

WHAT IS CLAIMED IS:

1 A reclosable package, comprising a pair of opposing wall panels joined along a pair of opposing sides and a bottom bridging the opposing sides to create a receptacle space having a mouth end opposite the bottom, a reclosable seal extending along the mouth end and including first and second opposing reclosable elements, the first and second reclosable elements being releasably engageable to each other; and a barrier partition comprising at least a first layer that is substantially impermeable to at least one of oxygen, nitrogen and carbon dioxide, the barrier partition extending substantially across the pair of opposing wall panels in the receptacle space and being located below the reclosable seal

2 The reclosable package of Claim 1 , wherein the barrier partition is formed by first and second fin portions extending downward from the respective first and second reclosable elements and are joined to each other

3 The reclosable package of Claim 2, wherein the first and second fin portions are joined to each other along a one-time breakable preferential area of weakness to inhibit tampering with the package prior to being opened

4 The reclosable package of Claim 3, wherein the preferential area of weakness is selected from the group consisting of a score line, a thinned line and a highly oriented region

5 The reclosable package of Claim 2, wherein the first and second fin portions are joined to each other along respective lower edges thereof

6 The reclosable package of Claim 2, wherein the first and second fin portions are extruded with each other so as to form a single continuous fin

7 The reclosable package of Claim 2, wherein a combination of the first and second fin portions has a generally U-shaped or V-shaped cross-sectional configuration

8 The reclosable package of Claim 1, wherein the barrier partition is formed by at least one integral extension of at least one opposing wall panel

9 The reclosable package of Claim 8, wherein the barrier partition is formed by integral extensions of the opposing wall panels 10 The reclosable package of Claim 1, wherein the first layer of the barrier partition comprises ethylene vinyl alcohol, polyvinyl alcohol, nylon, polyester, ethylene vinyl dichloride, liquid crystal polymer, polyvinyl chloride, polyvinylidene chloride, modified polyolefins with barrier properties, polyacrylonitrile, acrylonitriles copolymers, polyacetal, cellophane or combinations thereof

11 The reclosable package of Claim 10, wherein the first layer of the barrier partition comprises ethylene vinyl alcohol, nylon, polyvinylidene chloride or the combination thereof

12 The reclosable package of Claim 1, wherein the barrier partition includes an oxygen scavenger or an oxygen absorber

13 The reclosable package of Claim 1, wherein the barrier partition includes a filler

14 The reclosable package of Claim 13, wherein the filler is talc, clay, mica or a nanocomposite 15 The reclosable package of Claim 1 , wherein the barrier partition further includes a second layer, the second layer is a tie layer

16 The reclosable package of Claim 15, wherein the barrier partition further includes a third layer, the third layer is a tie layer and the first layer is located between the second and the third layers 17 The reclosable package of Claim 15, wherein the barrier partition further includes a third layer, the third layer comprises a polyolefin, the second layer is located between the first and the third layers

18 The reclosable package of Claim 15, wherein the barrier partition further includes a third layer and a fourth layer, the third layer is a tie layer, the fourth layer comprises a polyolefin and is located adjacent to the third layer, the third layer is located between the fourth and first layers, and the first layer is located between the second and third layers

19 The reclosable package of Claim 18, wherein the barrier partition further includes a fifth layer, the fifth layer comprises a polyolefin and is located adjacent to the second layer, the second layer is located between the fifth and first layers

20 The reclosable package of Claim 1 , wherein the first layer is nylon, ethylene vinyl alcohol, polyvinylidene chloride or combinations thereof

21. The reclosable package of Claim 17, wherein the first layer is nylon or ethylene vinyl alcohol, polyvinylidene chloride or combinations thereof.

22 The reclosable package of Claim 1, wherein the first reclosable element includes a first locking profile and the second reclosable element includes a second 5 locking profile, and further including a slider mechanism slidably mounted to the first and second locking profiles for movement between a closed position and an open position, the first and second profiles being engaged to each other while the slider mechanism is in the closed position, the first and second profiles being disengaged from each other in response to movement of the slider mechanism to the open position o 23 A reclosable package, comprising a pair of opposing wall panels joined along a pair of opposing sides and a bottom bridging the opposing sides to create a receptacle space having a mouth end opposite the bottom, a reclosable seal extending along the mouth end and including first and second s opposing tracks, the first and second opposing tracks including respective first and second profiles, the first and second opposing tracks being releasably engageable to each other, the first and second tracks being connected to one of the respective opposing wall panels, the first and second profiles including at least a first layer that is substantially impermeable to at least one of oxygen, nitrogen and carbon dioxide, and 0 barrier means being proximate to upper edges of the respective first and second profiles, the barrier means being substantially impermeable to at least one of oxygen, nitrogen and carbon dioxide

24 The reclosable package of Claim 23, wherein the barrier means includes first and second upstanding fins extending upward from the respective first and second 5 profiles, the first and second upstanding fins are detachably connected to the first and second profiles and are attached to each other

25 The reclosable package of Claim 24, wherein the first and second upstanding fins extend substantially across the mouth, and further including a slider mechanism slidably mounted to the first and second profiles for movement between a o closed position and an open position

26. The reclosable package of Claim 23, wherein the barrier means is a continuous bead of adhesive applied across the upper edges of the respective first and second profiles

27. The reclosat le package of Claim 23, wherein the barrier means includes an integral formation of the upper edges of the respective first and second profiles

28 The reclosable package of Claim 23, wherein the barrier means includes a continuous thermal seal of the upper edges of the respective first and second profiles 29. The reclosable package of Claim 23 further including a slider mechanism slidably mounted to the first and second profiles for movement between a closed position and an open position, the first and second profiles being engaged to each other while the slider mechanism is in the closed position, the first and second profiles being disengaged from each other in response to movement of the slider mechanism to the open position

30 The reclosable package of Claim 29, wherein the slider mechanism includes a separator finger disposed between the first and second profiles, the separator finger adapted to break a line of connection formed between the upper edges of the respective first and second profiles in response to movement of the slider from the closed position to the open position.

31 The reclosable package of Claim 23, wherein the barrier means comprises ethylene vinyl alcohol, polyvinyl alcohol, nylon, polyester, ethylene vinyl dichloride, liquid crystal polymer, polyvinyl chloride, polyvinylidene chloride, modified polyolefins with barrier properties, polyacrylonitrile, acrylonitriles copolymers, polyacetal, cellophane or combinations thereof

32 The reclosable package of Claim 31 , wherein the barrier means comprises ethylene vinyl alcohol, nylon, polyvinylidene chloride or combinations thereof

33 The reclosable package of Claim 23, wherein the barrier means further includes a second layer, the second layer is a tie layer

34 The reclosable package of Claim 33, wherein the barrier means further includes a third layer, the third layer is a tie layer and the first layer is located between the second and third layers

35 The reclosable package of Claim 23, wherein the barrier means includes an oxygen scavenger or an oxygen absorber

36 The reclosable package of Claim 23, wherein the barrier means includes a filler 37 The reclosable package of Claim 36, wherein the filler is talc, clay, mica or a nanocomposite

38 A reclosable package, comprising- a pair of opposing wall panels joined along a pair of opposing sides and a bottom bridging the opposing sides to create a receptacle space having a mouth end opposite the bottom, a reclosable seal extending along the mouth end and including first and second opposing reclosable elements, the first and second reclosable elements being releasably engageable to each other; and a barrier partition comprising at least a first layer that includes a material selected from the group consisting of vinyl alcohol, polyvinyl alcohol, nylon, polyester, ethylene vinyl dichloride, liquid crystal polymer, polyvinyl chloride, polyvinylidene chloride, modified polyolefins with barrier properties, polyacrylonitrile, acrylonitriles copolymers, polyacetals, cellophane or combinations thereof the barrier partition extending substantially across the pair of opposing wall panels in the receptacle space and being located below the recloseable seal

39 The reclosable package of Claim 38, wherein the barrier partition is formed by first and second fin portions extending downward from the respective first and second reclosable elements and are joined to each other 40 The reclosable package of Claim 39, wherein the first and second fin portions are joined to each other along a one-time breakable preferential area of weakness to inhibit tampering with the package prior to being opened

41 The reclosable package of Claim 40, wherein the preferential area of weakness is selected from the group consisting of a score line, a thinned line and a highly oriented region

42 The reclosable package of Claim 38, wherein the barrier partition is formed by at least one integral extension of at least one opposing wall panel

43 The reclosable package of Claim 38, wherein the first layer of the barrier partition comprises ethylene vinyl alcohol, nylon, polyvinylidene chloride or combinations thereof

44 The reclosable package of Claim 38, wherein the barrier partition further includes a second layer, the second layer is a tie layer 45 The reclosable package of Claim 44, wherein the barrier partition further includes a third layer, the third layer is a tie layer and the first layer is located between the second and the third layers

46 The reclosable package of Claim 44, wherein the barrier partition further includes a third layer, the third layer comprises a polyolefin, the second layer is located between the first and the third layers

47 The reclosable package of Claim 38, wherein the barrier partition includes an oxygen scavenger or an oxygen absorber

48 The reclosable package of Claim 38, wherein the barrier partition includes a filler

49 The reclosable package of Claim 48, wherein the filler is talc, clay, mica or a nanocomposite

50 A fastener to be used in a reclosable bag, the fastener comprising first and second opposing reclosable elements, the first and second reclosable elements being releasably engageable to each other, a first fin portion extending downward from the first reclosable element, the first fin portion comprising at least a first layer that is substantially impermeable to at least one of oxygen, nitrogen and carbon dioxide, and a second fin portion extending downward from the second reclosable element, the second fin portion comprising at least a first layer that is substantially impermeable to at least one of oxygen, nitrogen and carbon dioxide, the second fin portion and the first fin portion being joined to each other

51 The fastener of Claim 50, wherein the first and second fin portions are joined to each other along a one-time breakable preferential area of weakness to inhibit tampering with the package prior to being opened

52 The fastener of Claim 51, wherein the preferential area of weakness is selected from the group consisting of a score line, a thinned line and a highly oriented region

53 The fastener of Claim 50, wherein the first and second fin portions are joined to each other along respective lower edges thereof

54 The fastener of Claim 50, wherein the first and second fin portions are extruded with each other so as to form a single continuous fin 55 The fastener of Claim 50, wherein a combination of the first and second fin portions has a generally U-shaped or V-shaped cross-sectional configuration

56 The fastener of Claim 50, wherein the first layers of the first and second fin portions comprise material independently selected from the group consisting of ethylene vinyl alcohol, polyvinyl alcohol, nylon, polyester, ethylene vinyl dichloride, liquid crystal polymer, polyvinyl chloride, polyvinylidene chloride, modified polyolefins with barrier properties, polyacrylonitrile, acrylonitriles copolymers, polyacetal, cellophane and combinations thereof

57 The fastener of Claim 56, wherein the first layers of the first and second fin portions comprise material independently selected from the group consisting of ethylene vinyl alcohol, nylon, polyvinylidene chloride and combinations thereof

58 The fastener of Claim 56, wherein each of the first and second fin portions further includes a second layer, the second layer is a tie layer

59 The fastener of Claim 58, wherein each of the first and second fin portions further includes a third layer, the third layer is a tie layer and the first layer is located between the second and the third layers

60 The fastener of Claim 58, wherein each of the first and second fin portions further includes a third layer, the third layer is made from a polyolefin, the second layer is located between the first layer and the third layer 61 The fastener of Claim 50, wherein at least one of the fin portions includes an oxygen scavenger or an oxygen absorber

62 The fastener of Claim 50, wherein at least one of the fin portions includes a filler

63 The fastener of Claim 62, wherein the filler is talc, clay, mica or a nanocomposite

64 The fastener of Claim 50, wherein the first and second fin portions have an oxygen transmission rate less than 100 cm³ (mil)/100 in² (d)(atm) at 23°C as measured by ASTM D3985-81

65 The fastener of Claim 64, wherein the first and second fin portions have an oxygen transmission rate less than 20 cm¹ (mil)/100 in² (d)(atm) at 23°C as measured by ASTM D3985-81 66 The fastener of Claim 65, wherein the first and second fin portions have an oxygen transmission rate less than 10 cm³ (mil)/ 100 in² (d)(atm) at 23 °C as measured by ASTM D3985-81

67 A fastener to be used in a reclosable bag, the fastener comprising a first opposing track having a first profile, the first profile comprising at least a first layer that is substantially impermeable to at least one of oxygen, nitrogen and carbon dioxide, and a second opposing track having a second profile, the second profile comprising at least a first layer that is substantially impermeable to at least one of oxygen, nitrogen and carbon dioxide, the first and second opposing tracks being releasably engageable to each other

68 The fastener of Claim 67, wherein the first layer of the first and second profiles comprise material independently selected from the group consisting of ethylene vinyl alcohol, polyvinyl alcohol, nylon, polyester, ethylene vinyl dichloride, liquid crystal polymer, polyvinyl chloride, polyvinylidene chloride, modified polyolefins with barrier properties, polyacrylonitrile, acrylonitriles copolymers, polyacetal, cellophane and combinations thereof

69 The fastener of Claim 68, wherein the first layers of the first and second profiles comprise material independently selected from the group consisting of ethylene vinyl alcohol, polyvinylidene chloride, nylon and combinations thereof

70 The fastener of Claim 67, wherein each of the first and second profiles further includes a second layer, the second layer is a tie layer

71 The fastener of Claim 70, wherein each of the first and second profiles further includes a third layer, the third layer is a tie layer and the first layer is located between the second and the third layers

72 The fastener of Claim 67, wherein at least one of the first and second profiles includes an oxygen scavenger or an oxygen absorber

73 The fastener of Claim 67, wherein at least one of the first and second profiles includes a filler 74 The fastener of Claim 73, wherein the filler is talc, clay, mica or a nanocomposite 75 The fastener of Claim 67, wherein the first and second fin portions have an oxygen transmission rate less than 100 cm' (mil)/100 in² (d)(atm) at 23°C as measured by ASTM D3985-81.

76 The fastener of Claim 75, wherein the first and second fin portions have an oxygen transmission rate less than 20 cm³ (mil)/100 in² (d)(atm) at 23°C as measured by ASTM D3985-81

77 The fastener of Claim 76, wherein the first and second fin portions have an oxygen transmission rate less than 10 cm³ (mil)/100 in² (d)(atm) at 23°C as measured by ASTM D3985-81. 78 A process of applying a coating to a reclosable bag, the process comprising providing a reclosable bag, the reclosable bag comprising a pair of opposing wall panels joined along a pair of opposing sides and a bottom bridging the opposing sides to create a receptacle space having a mouth end opposite the bottom, a reclosable seal extending along the mouth end and including first and second opposing tracks, the first and second tracks including respective first and second profiles, the first and second opposing tracks being releasably engageable to each other, the first and second tracks being connected to the respective opposing wall panels, and applying a coating to at least a portion of the first and second tracks, the coating including at least a first layer that is substantially impermeable to at least one of oxygen, nitrogen and carbon dioxide

79 The process of Claim 78, wherein the first and second tracks further include respective first and second fin portions and the applying step includes applying the coating to at least a portion of the first and second profiles and the first and second fin portions

80 A reclosable package, comprising a pair of opposing wall panels joined along a pair of opposing sides and a bottom bridging the opposing sides to create a receptacle space having a mouth end opposite the bottom, a reclosable seal extending along the mouth end and including first and second opposing reclosable elements, the first and second reclosable elements being releasably engageable to each other, and a barrier partition formed by first and second fin portions extending downward from the respective first and second reclosable elements and being joined to each other, the barrier partition extending substantially across the pair of opposing wall panels in the receptacle space and being located below the recloseable seal, the barrier partition comprising at least a first layer that is substantially impermeable to at least one of oxygen, nitrogen and carbon dioxide.

81. A reclosable package, comprising: a pair of opposing wall panels joined along a pair of opposing sides and a bottom bridging the opposing sides to create a receptacle space having a mouth end opposite the bottom; a reclosable seal extending along the mouth end and including first and second opposing reclosable elements, the first and second reclosable elements being releasably engageable to each other; and a barrier partition formed by first and second fin portions extending downward from the respective first and second reclosable elements and being joined to each other, the barrier partition extending substantially across the pair of opposing wall panels in the receptacle space and being located below the recloseable seal, the barrier partition comprising at least a first layer that includes a material selected from the group consisting of vinyl alcohol, polyvinyl alcohol, nylon, polyester, ethylene vinyl dichloride, liquid crystal polymer, polyvinyl chloride, polyvinylidene chloride, modified polyolefins with barrier properties, polyacrylonitrile, acrylonitriles copolymers, polyacetals, cellophane or combinations thereof.