Abstract:
According to the invention, a patch is provided to be attached to the outside of the wall of the bag over the profile strip fastener assembly that is attached to the front panel of the package. The patch is made from a gas barrier type of substrate as to prevent oxygen and other gases from entering or leaving the perforations within the opening feature used to access the fastener assembly. The side of the patch that is in contact with the front panel of the bag includes an adhesive for securement to the package. A variety of adhesives can be utilized for securement depending on the arrangement of the perforations. Printing can be included on the outside of the patch to highlight the reclosable feature of the package thereby eliminating the need to modify the original printing on the package.

Description:
BACKGROUND OF THE INVENTION 
       [0001]    Reclosable packaging is particularly well suited for packaging food products when it is desired to repeatedly remove relatively small quantities of the food product. Recent improvements in reclosable packaging have included configuring packages to have integral zipper-type fastener assemblies. In such arrangements, the package is typically opened by cutting or tearing a portion of the package to gain access to the fastener assembly, with opening and closing of the profile strips of the fastener assembly thereafter permitting the package to be selectively opened and closed. 
         [0002]    While packages having the integrated profile strip fastener assemblies are becoming common in the market place, such arrangements have typically required specialized packaging machinery for forming and filling of such packages. 
         [0003]    U.S. Pat. No. 5,461,845 discloses a reclosable package, and method of formation, which is specifically configured to facilitate use on conventional, so called form, fill, and seal machinery. The package disclosed in the above referenced patent includes a profile fastener assembly which is configured such that a plurality of fastener assemblies can be provided on a continuous web of package forming material, with the web then stored in rolled form prior to use. The web of material with fastener assemblies can then be supplied to a conventional form, fill, and seal machine, with the machine operated in a generally conventional manner to package the product as desired. By the provision of the profile strip fastener assembly in the front wall portion of the package, convenient reclosability of the package is provided without resort to twist-tie fasteners, plastic clasps, or the like. The package disclosed includes a line of perforations in the front panel for accessing the fastener assembly. This access feature is necessary when the fastener assembly is in the front panel portion of the package since cutting or removing a portion of the top of the package would deem the reclosable fastener assembly useless. 
         [0004]    U.S. Pat. No. 5,806,984 also discloses a package in the form of a reclosable bag that includes a profile strip fastener assembly which is joined to the front wall of a bag body in a manner which permits formation of the bag in web form prior to use with a conventional form, fill, and seal machine. Notably, the profile strip fastener assembly includes a peelable seal, in addition to the closure formed by the interlocking profile strip of the assembly. In the preferred embodiment, the front wall of the bag body includes an elongated, frangibly removable portion which is substantially aligned with the fastener assembly. This removable portion provides access to the seal and interlocking profile strips of the fastener assembly after the portion is removed from the front wall of the bag. When packaging perishable products that must be packaged in a manner which limits the amount of oxygen to which the products are exposed through the remove able portion, the flanges of the fastener assembly can be formed from material which is substantially different than polyethylene for relatively low oxygen transmission. 
         [0005]    U.S. Pat. No. 6,079,878 also discloses a package in the form of a reclosable bag that includes a profile strip fastener assembly which is joined to the front wall of a bag body in a manner which permits formation of the bag in web form prior to use with a conventional form, fill, and seal machine. Notably, the sealing arrangement of the profile strip fastener assembly in combination with an improved opening feature with accurate center region that when separated from the front panel forms a convenient tab for simultaneously pulling open said joint and said fastener strips. Additionally, the sealing arrangement in combination with improved opening feature reduces the area within the seal thereby reducing the amount of oxygen to which the packaged product is exposed. Although when the opening feature utilizes perforations in the front panel for accessing the fastener assembly, the addition of a peelable seal along with barrier flange materials are again required. 
         [0006]    In summary the prior art teaches convenient front panel profile strip fastener assemblies that can be formed into reclosable packages using conventional form, fill, and seal machinery. When using front panel profile strip fastener assemblies some type of opening feature is necessary for accessing the fastener assemblies since the user of the package cannot merely remove the top portion of the package. When using opening features with front panel fastener arrangements that include perforations, the profile strip fastener assemblies must include additional features, such as barrier flanges and a peelable seal between the flanges, when making packages for use with products that are sensitive to oxygen transmission. 
       SUMMARY OF THE INVENTION 
       [0007]    According to the invention, a patch is provided to be attached to the outside of the wall of the bag over the profile strip fastener assembly that is attached to the front panel of the package. The patch is made from a gas barrier type of substrate as to prevent oxygen and other gases from entering or leaving the perforations within the opening feature used to access the fastener assembly. The side of the patch that is in contact with the front panel of the bag includes an adhesive for securement to the package. A variety of adhesives can be utilized for securement depending on the arrangement of the perforations. Printing can be included on the outside of the patch to highlight the reclosable feature of the package thereby eliminating the need to modify the original printing on the package. The use of the patch not only solves the gas barrier problem that has plagued packages with front panel zipper arrangements, but also reduces the amount of time it takes to change an existing printed packaging over to new reclosable packaging graphics. The present invention is particularly well suited for packaging snack foods, such as, corn and potato chips which require gas barrier packaging. In addition the patch can be configured to eliminate tear propagation around the bag opening once the zipper has been accessed. 
         [0008]    A package in the form of a reclosable bag embodying the principles of the present invention includes a profile strip fastener assembly which is joined to a front wall of a bag body. The profile strip fastener includes an openable mouth formed by interlocking profile strips, allowing access to the contents of the bag. The front wall includes a joint defined by a pattern of perforations, the joint in registry with the openable mouth of the profile strip fastener assembly and a protective patch covering the perforations. Notably, the protective patch, in addition to the closure formed by the interlocking profile strips of the assembly, enhances the sealing integrity of the fastener assembly during package formation, filling, and subsequent storage and use. Oxygen barrier packaging can be produced in accordance with the principles disclosed herein by the provision of protective patch and bag film materials exhibiting oxygen-barrier properties. 
         [0009]    In accordance with the illustrated embodiment, the present reclosable bag includes a bag body formed from a rectangular sheet of film material, such as plastic film material or the like. The bag body has a top end, a bottom end, a front wall, and a back wall, wherein the front wall is joined to the back wall by upper and lower seams respectively provided at the top and bottom ends of the bag body. The bag and profile strip assembly are configured to be compatible with a conventional form, fill and seal machine. 
         [0010]    A reclosable profile strip fastener assembly is joined to the front wall of the bag body and comprises first and second interlocking profile strips which respectively extend along the length of the fastener assembly. The profile strips are configured for releasable interlocking engagement with each other by the provision of at least one elongated protuberance on one of the profile strips, and at least one groove defined by the other of the profile strips for respectively releasably receiving the protuberance. 
         [0011]    The fastener assembly is specifically configured for independent securement to the inside surface of the front wall of the bag body, and to this end, the first profile strip of the assembly includes a first body flange portion joined to an inside surface of the front wall. Similarly, the second profile strip includes a second body flange portion joined to the inside surface of the front wall of the bag body. 
         [0012]    In the preferred embodiment, the front wall of the bag body includes an elongated, frangibly openable joint which is substantially aligned with the fastener assembly. This openable joint provides access to the openable mouth formed by the interlocking profile strips of the fastener assembly after the joint is opened on the front wall of the bag body. The provision of this openable joint in the bag body desirably provides tamper-evidence of opening of the bag. The joint can be a substantially linear arrangement of perforations or a rectangular or oval pattern of perforations which defines a removable or partially removable panel. The first and second body flange portions are sealed to the front wall with a continuous perimeter seal which surrounds the joint. The second profile strip body flange portion can also be sealed along its bottom edge region to the bag front wall. A protective patch completely covering the openable joint. 
         [0013]    Other features and advantages of the present invention will become readily apparent from the following detailed description, the accompanying drawings, and the appended claim. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0014]      FIG. 1  is a perspective view of a package in the form of a reclosable bag with a first embodiment of a protective patch of the present invention; 
           [0015]      FIG. 2  is a perspective view of a package with a first embodiment of a protective patch partially removed; 
           [0016]      FIG. 3  is a cross-sectional view taken along lines  3 - 3  of  FIG. 1 ; 
           [0017]      FIG. 4  is a cross-sectional view taken along lines  4 - 4  of  FIG. 1 ; 
           [0018]      FIG. 5  is a perspective view of a package in the form of a reclosable bag with a second embodiment of a protective patch of the present invention; 
           [0019]      FIG. 6  is a perspective view of a package with a second embodiment of a protective patch partially removed; 
           [0020]      FIG. 7  is a cross-sectional view taken along lines  7 - 7  of  FIG. 5 ; 
           [0021]      FIG. 8  is a cross-sectional view taken along lines  8 - 8  of  FIG. 5 . 
       
    
    
     DETAILED DESCRIPTION 
       [0022]    While the present invention is susceptible of embodiment in various forms, there is shown in the drawings and will hereinafter be described a presently preferred embodiment of the invention, with the understanding that the present disclosure is to be considered as an exemplification of the invention, and is not intended to limit the invention to the specific embodiments illustrated. 
         [0023]    With reference now to the drawings, a package in the form of a reclosable bag  10  is illustrated which embodies the principles of the present invention. It is contemplated that the bag  10  be formed from suitable plastic film materials or the like, but it is within the purview of the present invention to form the bag from paper or paper-like materials. As will hereinafter be described, bag  10  is specifically configured in a manner which facilitates formation of the bag from a substantially continuous web of film material, to which fastener assemblies have been previously applied, for use in a so-called form, fill, and seal apparatus for packaging of food products, or non-food products. For example, the present package can be configured for packaging of non-food items such as hardware articles or the like, wherein repeated opening and closing of the package is desired. 
         [0024]    The reclosable bag  10  is formed from a generally rectangular sheet of film material, and includes a top end generally designated  12 , a bottom end generally designated  14 , and front and back walls  16  and  18 . The front and back walls are joined to each other by upper and lower seams  20 ,  22  (shown schematically as tracks), respectively provided at top and bottom ends  12  and  14  of the bag. Lateral edges of the rectangular sheet of film material from which the bag body is formed are joined to each other along a back seam  24  extending vertically along back wall  18 . The seams  20 ,  22 , and  24  can be formed adhesively, or by heat-sealing as is known in the art. As will be appreciated, a bag configured in accordance with the present invention can be formed from two rectangular sheets of bag material joined at their peripheral regions to form a package, with the fastener assembly having a length corresponding to the width of the sheet of bag material to which the fastener assembly is joined. 
         [0025]    Reclosable bag  10  includes profile strip fastener assembly  26  which is sealingly mounted on the inside surface of front wall  16 . In order to permit use of the present bag with conventional packaging equipment, fastener assembly  26  has a length no more than one-half the width of the rectangular sheet of film material from which the bag body is formed. In practice, a substantially continuous sheet of film material is provided with a plurality of the fastener assemblies  26  mounted thereon at spaced locations, which spacing corresponds to the length dimension of the bags ultimately to be formed. For use, this web of film material (with the fastener assemblies mounted thereon) is supplied to a form, fill, and seal apparatus which operates to form a series of the bags  10 , in end-to-end relationship, by formation of back seam  24 , bottom seam  22 , and top seam  20 , as food product is supplied to the individual bags being formed. After formation and filling, the individual bags are ordinarily separated from each other for packaging and shipment, as may be required. 
         [0026]    With particular reference to  FIG. 3  the fastener assembly  26  includes a first elongated profile strip  28 , and a second elongated profile strip  30  which are configured for releasable interlocking engagement with each other. While the specific configuration of the profile strips can be varied while keeping with the principles disclosed herein, it is contemplated that one of the profile strips (first strip  28  in the illustrated embodiment) includes a body  32  which defines at least one elongated groove  34 , while the other profile strip (second strip  30 ) includes a body  36  which defines at least one protuberance  38 , configured for respective interlocking engagement with the groove  34   a.  As will be recognized by those familiar with the art, the number of grooves and protuberances, and their respective disposition on the first and second profile strips, can be varied while keeping with the principles disclosed herein. 
         [0027]    The fastener assembly  26  is sealingly mounted on the inside surface of the front wall  16  of the body of the reclosable bag  10 , and to this end, each of the profile strips  28 ,  30 , includes an elongated flange portion joined to the inside surface of the front wall. Specifically, first profile strip  28  includes a first body flange portion  40  which is joined to the inside surface of front wall  16  by elongated seal region  41 . Similarly, second profile strip  30  includes a second body flange portion  42  (including upper and lower flange regions which respectively extend upwardly and downwardly from the body  36 ) which is joined to the inside surface of front wall  16  by lower elongated seal region  43  (shown schematically as tracks), and upper elongated seal region  44 . Elongated seal regions  41 ,  44  may be arranged in the form of a continuous oval seal including end seal regions  50  (shown schematically as tracks) described below. It is within the purview of the present invention that seal regions  41 ,  43 ,  44 ,  50  may be formed with the use of suitable adhesive, but are preferably provided by heat-sealing (sometimes referred to as “lock-up” or “destruct” sealing). The seals  41 ,  43 ,  44 ,  50  are preferably continuous for strength and for sealing of the contents of the bags, but discontinuous seals may be suitable for some applications. 
         [0028]    As illustrated in  FIGS. 2 and 3 , access to the fastener assembly  26  from the exterior of the package is preferably provided by the provision of an elongated, frangible region, substantially aligned with fastener assembly  26 , and in particular in the region between seal  41  and seal  44 . In the illustrated embodiment the frangible region comprises an elongated frangible joint  52  formed through the front wall  16  of the bag body. 
         [0029]    The joint  52  is preferably defined by a preferentially weakened frangible portion of the bag front wall  16 , such as by perforations  53 , which when broken or ripped, result in formation of an elongated opening by which access to fastener assembly  26  is provided. An enlarged perforation  53   a  is preferably located at each end of the joint to prevent further ripping. As shown in  FIG. 2 , the joint has an arcuate center region  52   c  formed by perforations  53  which, when separated, forms a convenient tab  52   d  for handling by the user to pull apart the remainder of the opening and also thereafter to open the joint  52  of the bag. Perforators  53  in the center region  52   c  could be made longer (i.e., slits) so as to make them easier to grip and open. 
         [0030]    Protective patch  31  is secured over joint  52  which is desirable for use with certain perishable products that when packaged in bag  10  in a manner which limits the amount of oxygen and moisture to which the products are exposed. The protective patch  31  includes a body portion  31   a  that is preferably formed from materials which exhibit relatively low oxygen transmission rates, such as materials including nylon, ethylene vinyl alcohol (EVOH), polyester (PET), Metallized foils, bi-oriented polypropylene (BOPP), Polypropylene, Polystyrene, Polyethylene, Saran (PUDC), or combinations thereof, or the like. The oxygen transmission rate through the protective patch should not be greater than 2.5 cc-mil/100 square inches/24 hrs at 23 degrees Celsius and 75% relative humidity. Although for or certain applications, the oxygen transmission rate should below 0.25 5 cc-mil/100 square inches/24 hrs at 23 degrees C. and 90% relative humidity. 
         [0031]    In addition, the body portion  31   a  can also be made from materials that exhibit relatively low moisture vapor transmission rates such as, Polyethylene, in particular high density polyethylene (HDPE), Oriented Polypropylene (OPP), Metallized PET, Polyester, or the like. The moisture vapor transmission rate through the protective patch  31  should not be greater than 1.1 gm-mil/100 square inches/24 hrs at 30 degrees Celsius and 90% relative humidity. Although for certain applications, the moisture vapor transmission rate should be below 0.5 gm-mil/100 square inches/24 hrs at 30 degrees Celsius and 90% relative humidity. One side of body portion  31   a  contains an adhesive  31   b  for use in securement to the front panel  16  of bag  10  completely covering joint  52 . Adhesive  31   b  has a peelable strength so as to allow it to be removed from bag  10  without damaging front panel  16 . Protective patch  131  is designed to securely cover joint  152  as to eliminate excessive amounts of water vapor and gases from entering bag  10 , but allowing the user to peel patch  31  off when accessing the reclosable fastener  26  through joint  52 . The adhesive  31   b  is preferably made from any suitable adhesive known in the art of making pressure sensitive labels such as Hot Melt, Acrylic Emulsions, Transfer Adhesives, glue, Chemical Reactive Type adhesives, but could also be formed from other suitable adhesives as well. 
         [0032]      FIGS. 3-4  illustrate an alternate embodiment of the present invention. A reclosable bag  100  is formed from a generally rectangular sheet of film material, and includes a top end generally designated  112 , a bottom end generally designated  114 , and front and back walls  116  and  118 . The front and back walls are joined to each other by upper and lower seams  120 ,  122  (shown schematically as tracks), respectively provided at top and bottom ends  112  and  114  of the bag. Lateral edges of the rectangular sheet of film material from which the bag body is formed are joined to each other along a back seam  124  extending vertically along back wall  118 . The seams  120 ,  122 , and  124  can be formed adhesively, or by heat-sealing as is known in the art. As will be appreciated, a bag configured in accordance with the present invention can be formed from two rectangular sheets of bag material joined at their peripheral regions to form a package, with the fastener assembly having a length corresponding to the width of the sheet of bag material to which the fastener assembly is joined. 
         [0033]    Reclosable bag  100  includes profile strip fastener assembly  126  which is sealingly mounted on the inside surface of front wall  116 . The fastener assembly  126  includes a first elongated profile strip  128 , and a second elongated profile strip  130  which are configured for releasable interlocking engagement with each other. While the specific configuration of the profile strips can be varied while keeping with the principles disclosed herein, it is contemplated that one of the profile strips (first strip  128  in the illustrated embodiment) includes a body  132  which defines at least one protuberance  134 , while the other profile strip (second strip  130 ) includes a body  136  which defines at least one groove  138  configured for respective interlocking engagement with the protuberance  134 . As will be recognized by those familiar with the art, the number of grooves and protuberances, and their respective disposition on the first and second profile strips, can be varied while keeping with the principles disclosed herein. 
         [0034]    The fastener assembly  126  is sealingly mounted on the inside surface of the front wall  116  of the body of the reclosable bag  110 , and to this end, each of the profile strips  128 ,  130 , includes an elongated flange portion joined to the inside surface of the front wall. Specifically, first profile strip  128  includes a first body flange portion  140  which is joined to the inside surface of front wall  116  by elongated seal region  141  (shown schematically as tracks). Similarly, second profile strip  130  includes a second body flange portion  142  (including upper and lower flange regions which respectively extend upwardly and downwardly from the body  136 ) which is joined to the inside surface of front wall  116  by lower elongated seal region  144  (shown schematically as tracks). Elongated seal regions  141 ,  144  may be arranged in the form of a continuous oval seal including end seal regions  150  (shown schematically as tracks) described below. It is within the purview of the present invention that seal regions  141 ,  144 ,  150  may be formed with the use of suitable adhesive, but are preferably provided by heat-sealing (sometimes referred to as “lock-up” or “destruct”sealing). The seals  141 ,  144 ,  150  are preferably continuous for strength and for sealing of the contents of the bags, but discontinuous seals may be suitable for some applications. 
         [0035]    The flange portions and the bodies of the first and second profile strips  128 ,  130  can be composed of similar materials and constructed as described for the previous embodiment. 
         [0036]    The profile strips are sealed at opposite ends in similar fashion as described in the previous embodiment. The end seals  150  can be substantially identical to the configuration of the end seals  50  shown in  FIG. 4 . That is, the body flange portions  140 ,  142  are sealed to each other and each to the front wall  116  vertically between the seals  141 ,  144 . The bodies  132 ,  136  can be compressed and sealed together as shown in  FIG. 4  with regard to the bodies  32 ,  36 . The fastener assembly embodying the principles of the present invention can include a secondary, peelable seal  147  which detachably joins the profile strips to each other, apart from the releasable engagement of protuberances  134  in the grooves  138 . 
         [0037]    As will be appreciated, the secondary peelable seal  147  preferably is configured to extend substantially the entire length of the fastener assembly  126 , thus desirably acting to provide an additional seal for the contents of the bag  100  in addition to the seal provided by interlocked portions  134 ,  138  of the profile strips  128 ,  130 . Further sealing of the contents of the bag against air and moisture transmission is preferably effected by the provision of the end seals  150  at respective opposite lateral ends of the fastener assembly  126 . 
         [0038]    As illustrated in  FIGS. 5 and 6 , access to the fastener assembly  126  from the exterior of the package is preferably provided by the provision of an elongated, frangible region, substantially aligned with fastener assembly  126 , and in particular in the region between seal  141  and seal  144 . In the illustrated embodiment the frangible region comprises an elongated substantially rectangular or oval frangible joint  152  formed through the front wall  116  of the bag body. 
         [0039]    The joint  152  is preferably defined by a preferentially weakened frangible portion of the bag front wall  116 , such as by perforations  153 , which when broken or ripped, result in formation of an elongated opening  154  by which access to fastener assembly  126  is provided. As shown in  FIG. 5 , the joint has arcuate end regions  152   c  which, when separated, form convenient tabs  152   d  for handling by the user to pull apart the remainder of the opening  154 . Alternatively, a single tab  152   d  can be provided at only one end of the joint  152 . The joint  152  defines a removable panel  155  which, once removed, provides access to the profile strip assembly  126  as well as serving as tamper-indication. 
         [0040]    Opening of the joint  152  and removal of the panel  155  permits opening of profile strips  128 ,  130 , thus permitting access to the contents of the package. 
         [0041]    Protective patch  131  is secured over joint  152  which is desirable for use with certain perishable products that when packaged in bag  110  in a manner which limits the amount of oxygen and moisture to which the products are exposed. The protective patch  131  includes a body portion  131   a  that is preferably formed from materials which exhibit relatively low oxygen transmission rates, such as materials including nylon, ethylene vinyl alcohol (EVOH), polyester (PET), Metallized foils, bi-oriented polypropylene (BOPP), Polypropylene, Polystyrene, Polyethylene, Saran (PUDC), or combinations thereof, or the like. The oxygen transmission rate through the protective patch should not be greater than 2.5 cc-mil/100 square inches/24 hrs at 23 degrees Celsius and 75% relative humidity. Although for or certain applications, the oxygen transmission rate should below 0.25 5 cc-mil/100 square inches/24 hrs at 23 degrees C. and 90% relative humidity. 
         [0042]    In addition, the body portion  131   a  can also be made from materials that exhibit relatively low moisture vapor transmission rates such as, Polyethylene, in particular high density polyethylene (HDPE), Oriented Polypropylene (OPP), Metallized PET, Polyester, or the like. The moisture vapor transmission rate through the protective patch  131  should not be greater than 1.1 gm-mil/100 square inches/24 hrs at 30 degrees Celsius and 90% relative humidity. Although for certain applications, the moisture vapor transmission rate should be below 0.5 gm-mil/100 square inches/24 hrs at 30 degrees Celsius and 90% relative humidity. One side of body portion  31   a  contains an adhesive  131   b  for use in securement to the front panel  116  of bag  110  completely covering joint  152 . Adhesive  131   b  has a peelable strength so as to allow it to be removed from bag  10  without damaging front panel  116 . Protective patch  131  is designed to securely cover joint  152  as to eliminate excessive amounts of water vapor and gases from entering bag  110 , but allowing the user to peel patch  131  off when accessing the reclosable fastener  126  through joint  152 . The adhesive  131   b  is preferably made from any suitable adhesive known in the art of making pressure sensitive labels such as Hot Melt, Acrylic Emulsions, Transfer Adhesives, glue, Chemical Reactive Type adhesives, but could also be formed from other suitable adhesives as well.