Patent Publication Number: US-6659643-B2

Title: Barrier arrangements for plastic bags

Description:
FIELD OF THE INVENTION 
     The invention relates to a reclosable fastener assembly for use with a plastic bag. Specifically, the reclosable fastener assembly with a tear-openable barrier arrangement is sealed to a single film wall of the plastic bag, with the barrier arrangement providing the sealing features of barrier material to the contents of the bag before the barrier arrangement is torn open. 
     DESCRIPTION OF THE PRIOR ART 
     The present invention relates to improvements in the bag-making art and may be practiced in the manufacture of reclosable thermoplastic bags and packages of the kind that may be used for various consumer products. Such reclosable thermoplastic bags or packages often include a seal to contain the package moisture and/or to render the package airtight prior to an initial opening of the bag or package. A reclosable fastener assembly protects any remainder of the product therein after the initial opening. 
     The indicated art is fairly well developed but nevertheless remains open to improvements contributing to the storing qualities of the reclosable bag. In the prior art, Yaeger (U.S. Pat. No. 5,461,845) discloses a reclosable bag and a method of making the bag. The bag has a reclosable fastener assembly connected to a single wall of film used to make the reclosable bag. 
     It is also known in the art that the sealant, strength and barrier layers of barrier material provide a much higher shield to the transmission of gases and water vapor than other films used in bag manufacturing. An improvement in reclosable bags of the type described above would be to provide various barrier arrangements of barrier material as part of the reclosable fastener assembly, thereby enhancing the barrier properties of the reclosable bag. 
     SUMMARY OF THE INVENTION 
     Accordingly, the present invention relates to a fastener assembly and a reclosable bag with the fastener assembly where the fastener assembly is connected to a single film wall of the bag. The fastener assembly generally comprises a strip formed of barrier material having a score line or line of weakness extending along a length of the strip of barrier material with the line of weakness not interfering with the barrier properties of the strip of barrier material. A first interlocking profile is connected to the strip of barrier material and extends parallel to the line of weakness. A mating profile flange is joined to the strip of barrier material on a side of the line of weakness opposite to the first interlocking profile, the mating profile flange including a second interlocking profile mateable with the first interlocking profile. A peel seal feature or closure flange may also be part of the fastener assembly. 
     In a first use of the fastener assembly with a reclosable bag, a bag is formed from a barrier film material with the bag including front and rear walls, a bottom, top and sides with a line of weakness extending along the bag front wall between the sides. The strip of barrier material of the fastener assembly is joined by a barrier seal to the interior of the bag front wall with the barrier seal encompassing the bag front wall line of weakness and the barrier material line of weakness. In a second use of the fastener assembly, the fastener assembly includes the arrangement of the first use except that the barrier strip includes both interlocking profiles. This is accomplished by the use of an extended barrier strip that bends at an upper section with the two interlocking profiles facing each other on the inner faces of the barrier flange, thereby forming the reclosable fastener portion. 
     In a third use of the fastener assembly with a reclosable bag, a bag is formed from a barrier film material with the bag including front and rear walls, a bottom, top and sides with a line of weakness extending along the bag front wall between the sides. As part of the fastener assembly, the strip of barrier material is sealed to a flange of the first interlocking profile along a seal line extending between the line of weakness and the first interlocking profile. The strip of barrier material of the fastener assembly is joined by a barrier seal to the interior of the bag front wall and encompasses the bag front wall line of weakness and the barrier material line of weakness. 
     In a fourth use of the fastener assembly with a reclosable bag, a bag is formed from a barrier film material with the bag including front and rear walls, a bottom, top and sides with a line of weakness extending along the bag front wall between the sides. A barrier seal encompassing the bag wall line of weakness seals the strip of barrier material to an exterior surface of the front wall. A flange of the fastener assembly having the first interlocking profile is connected to an interior surface of the front wall on one side of the bag front wall line of weakness. The mating profile flange is joined to the interior of the front wall on an opposite side of the bag front wall line of weakness. 
     In a fifth use of the fastener assembly with a reclosable bag, a bag is formed from a barrier film material with the bag including front and rear walls, a bottom, top and sides with a line of weakness extending along the bag front wall between the sides. The strip of barrier material of the fastener assembly is connected to the first interlocking profile. A second profile having a flange is joined to an exterior of the front wall, with the second profile including an interlocking member mateable with the first interlocking profile. A barrier seal encompasses the mateable profiles and the front wall line of weakness, with the barrier seal joining the second profile flange to the front wall on one side of the mateable profiles and the strip of barrier material to the front wall on the opposite side of the mateable profiles. A peel seal joins the barrier strip to the second profile flange on a side of the mateable profiles opposite the line of weakness. 
     In a sixth use of the fastener assembly with a reclosable bag, a bag is formed from a barrier film material with the bag including front and rear walls, a bottom, top and sides with a line of weakness extending along the bag front wall between the sides. A strip of barrier material of the fastener assembly is connected to the first interlocking profile. A second profile having a flange is joined to an interior of the front wall, with the second profile including an interlocking member mateable with the first interlocking profile. A barrier seal encompasses the mateable profiles and the front wall line of weakness with the barrier seal joining the second profile flange to the front wall on one side of the mateable profiles and the strip of barrier material to the front wall on the opposite side of the mateable profiles. A peel seal joins the barrier strip to the second profile flange on the side of the mateable profiles with the line of weakness. In a seventh use of the fastener assembly with a reclosable bag, the fastener assembly includes the arrangement of the sixth use except that the barrier strip is extended. The extended barrier strip is sealed to the inside of the front on a face of the strip opposite to that of the first interlocking member. 
    
    
     DESCRIPTION OF THE DRAWINGS 
     Further objects and advantages of the invention will become apparent from the following description and claims and from the accompanying drawings, wherein: 
     FIG. 1 is a front view of a fastener assembly with a barrier arrangement of a first and second use of the present invention depicting the fastener assembly attached to a reclosable bag; 
     FIG. 2 is a cross-sectional view (exaggerated in a horizontal direction for purposes of illustration) of a fastener assembly of the first use of the present invention with the fastener assembly shown in a closed position and with the view taken from reference line  2 — 2  of FIG. 1; 
     FIG. 3 is a cross-sectional view (exaggerated in a horizontal direction for purposes of illustration) of the fastener assembly of the first use of the present invention with the fastener assembly shown in an opened position; 
     FIG. 4 is a cross-sectional view (exaggerated in a horizontal direction for purposes of illustration) of the fastener assembly of the second use of the present invention with the fastener assembly shown in a closed position and with the view taken from reference line  4 — 4  of FIG. 1; 
     FIG. 5 is a cross-sectional view (exaggerated in a horizontal direction for purposes of illustration) of the fastener assembly of the second use of the present invention with the fastener assembly shown in an opened position; 
     FIG. 6 is a front view of a fastener assembly with a barrier arrangement of a third use of the present invention depicting the fastener assembly attached to a reclosable bag; 
     FIG. 7 is a cross-sectional view (exaggerated in a horizontal direction for purposes of illustration) of the fastener assembly of the third use of the present invention with the fastener assembly shown in a closed position and with the view taken from reference line  7 — 7  of FIG. 6; 
     FIG. 8 is a cross-sectional view (exaggerated in a horizontal direction for purposes of illustration) of the fastener assembly of the third use of the present invention with the fastener assembly shown in an opened position; 
     FIG. 9 is a front view of a fastener assembly with a barrier arrangement of a fourth use of the present invention depicting the fastener assembly attached to a reclosable bag; 
     FIG. 10 is a cross-sectional view (exaggerated in a horizontal direction for purposes of illustration) of the fastener assembly of the fourth use of the present invention with the fastener assembly shown in a closed position and with the view taken from reference line  10 — 10  of FIG. 9; 
     FIG. 11 is a cross-sectional view (exaggerated in a horizontal direction for purposes of illustration) of the fastener assembly of the fourth use of the present invention with the fastener assembly shown in an opened position; 
     FIG. 12 is a front view of a fastener assembly with a barrier arrangement of a fifth use of the present invention depicting the fastener assembly attached to a reclosable bag; 
     FIG. 13 is a cross-sectional view (exaggerated in a horizontal direction for purposes of illustration) of the fastener assembly of the fifth use of the present invention with a peelable seal shown in a closed position and with the view taken from reference line  13 — 13  of FIG. 12; 
     FIG. 14 is a cross-sectional view (exaggerated in a horizontal direction for purposes of illustration) of the fastener assembly of the fifth use of the present invention with a peelable seal shown in an opened position; 
     FIG. 15 is a front view of a fastener assembly with a barrier arrangement of a sixth and a seventh use of the present invention depicting the fastener assembly attached to a reclosable bag; 
     FIG. 16 is a cross-sectional view (exaggerated in a horizontal direction for purposes of illustration) of the fastener assembly of the sixth use of the present invention with a peelable seal shown in a closed position and with the view taken from reference line  16 — 16  of FIG. 15; 
     FIG. 17 is a cross-sectional view (exaggerated in a horizontal direction for purposes of illustration) of the fastener assembly of the sixth use of the present invention with a peelable seal shown in an opened position; 
     FIG. 18 is a cross-sectional view (exaggerated in a horizontal direction for purposes of illustration) of the fastener assembly of the seventh use of the present invention with a peelable seal shown in a closed position and with the view taken from reference line  18 — 18  of FIG. 16; 
     FIG. 19 is a cross-sectional view (exaggerated in a horizontal direction for purposes of illustration) of the barrier arrangement of the seventh use of the present invention with a peelable seal shown in an opened position; and 
     FIG. 20 is a detail view of the scored cut used on the barrier flanges and barrier tape in the uses of the present invention. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     Referring now to the drawings in detail wherein like numerals indicate like elements throughout the several views, a reclosable fastener assembly  10  in a first and second use of the present invention is shown in FIG. 1 as being attached to an associated bag  18 . In the figure, the reclosable fastener assembly  10  including a barrier arrangement is attached to a front wall  14  of the reclosable plastic bag  18 . 
     As shown in FIG. 2, a barrier flange  20  is sealed by an oval barrier seal  22  to the inside of the front wall  14 . The oval barrier seal  22 , and the tacking seals described in the specification, may be accomplished by conventional heat-sealing or any other sealing process known to those skilled in the art. The distinction between the barrier and tack sealing being that the barrier seals preclude air or liquid from passing whereas the tacking seals do not necessarily do so. Also, even though an oval barrier seal is preferred, barrier seals of alternate shapes known to those skilled in the art may be used. 
     A lower section of the barrier flange  20  of the fastener assembly  10  is sealed to the front wall  14  at a tack seal  24 . The tack seal  24  provides stability for the barrier strip when an interlocking profile  26  of the barrier flange  20  is accessed. The interlocking profile  26  of the figure is shaped to include a protuberance  28 , which is interlockingly received in a groove  30  of an interlocking profile  32 . However, other fasteners of interlocking profiles may be used by those skilled in the art. An interlocking profile  32  adapted to mate with interlocking profile  26  is integral to a mating profile flange  34 . The mating profile flange  34  is sealed to the barrier flange  20  at a tack seal  36 , with the tack seal providing an attachment area to the barrier flange  20  even when the interlocking profiles  26  and  32  are separated from one another. 
     To access the interlocking profiles  26  and  32  in order to open the reclosable bag  18 , the front wall  14  is provided with a line of weakness  40 . The line of weakness  40  may be a scoring, dimpling or perforation of the front wall  14  in a longitudinally extending direction between the sides of the reclosable bag  18  and within the oval barrier seal  22 . The line of weakness  40  facilitates rupturing of the front wall  14  to provide an opening of the reclosable bag, which in turn allows access to the barrier flange  20 . A single line of weakness  40  is shown and referenced in the following figures; however, a multi-line perforation may be substituted. 
     To access the interlocking profiles  26  and  32 , the barrier flange  20  has a scored cut  42  which extends partially through the barrier strip between the sides of the reclosable bag  18  encompassed by the oval barrier seal  22 . A single scored cut  42  is shown and referenced in the following figures; however, a multi-line scored cut may be substituted. The scored cut  42  allows the user to tear open the reclosable bag but is shallow enough so that the barrier attributes of the barrier flange  20  are maintained before the barrier flange is torn through. FIG. 20, which is later discussed, shows a detail of the score cut  42  and the affected layers of the barrier flange  20 . 
     As shown in FIG. 3, when the line of weakness  40  and the scored cut  42  are opened, access is provided to the interlocking profiles  26  and  32 . The oval barrier seal  22  and the tack seal  36  secure the mating profile flange  34  to the front wall so that the sole pathway  44  to the bag interior is through the profiles when the line of weakness  40  and the scored cut  42  are opened. The pathway  44  allows the user to gain access to the interlocking profiles  26 ,  32  and to thereby gain access to the contents of the reclosable bag  18 . 
     A second use of the fastener assembly  10  is shown in FIG.  4 . In the figure the barrier flange  20  is elongated and bent at an upper section and extended to include the interlocking profile  32 , thereby allowing the interlocking profile  32  to be positioned opposite the interlocking profile  26 . As shown in FIG. 5, when the line of weakness  40  and the scored cut  42  are opened, the oval barrier seal  22  secures the barrier flange  20  to the front wall so that the pathway  44  to the bag interior is through the interlocking profiles. That is, the pathway  44  allows the user to gain access to the interlocking profiles  26 ,  32  and to thereby gain access to the contents of the reclosable bag  18 . 
     A third use of the fastener assembly  10  of the present invention is shown in FIGS. 6,  7  and  8 . In the front view of FIG. 6, a reclosable fastener assembly  10  including a barrier arrangement is attached by an oval barrier seal  22  to the front wall  14  of the reclosable plastic bag  18 , with a line of weakness  40  within the oval barrier seal. In the cross-sectional view of FIG. 7, a strip of barrier tape  48  is sealed by the oval barrier seal  22  to the inside of the front wall  14 . The oval barrier seal  22 , along with the barrier tape  48 , prevents air or liquids from entering or leaving the reclosable bag  18  even if the front wall  14  in the area encompassed by the oval barrier seal  22  is ruptured. A closure flange  50  is sealed to the barrier tape  48  at a tack seal  52  and to the front wall at a seal  24  below the lower edge of the strip of barrier tape  48 . The tack seals  24  and  52  provide stability for the closure flange when an interlocking profile  26  of the closure flange  50  is accessed. The interlocking profile  26  is interlockable with an interlocking profile  32  of a mating profile flange  34 . The mating profile flange  34  is sealed to the strip of barrier tape  48  at a tack seal  36 , with the tack seal  36  providing an attachment area to the strip of barrier tape  48  even when the interlocking profiles  26  and  32  are separated from one another. 
     To access the strip of barrier tape  48 , the front wall  14  of the reclosable bag  18  is provided with a line of weakness  40 . To access the interlocking profiles  26  and  32  in order to open the bag, the strip of barrier tape  48  includes a scored cut  42 . The scored cut  42  of the strip of barrier tape  48  allows the user to tear through the barrier tape, but is shallow enough so that the barrier attributes of the barrier tape are maintained before it is torn through. FIG. 20, which is later discussed, shows a detail of the scored cut  42  and the affected layers of the barrier tape  48 . 
     As shown in FIG. 8, when the line of weakness  40  and the scored cut  42  are opened, access is provided to the interlocking profiles  26  and  32 . The oval barrier seal  22  and the tack seal  36  secure the mating profile flange  34  and the closure flange  50  to the front wall so that the sole pathway  44  to the bag interior is through the profiles when the line of weakness  40  and the scored cut  42  are opened. The pathway  44  allows the user to gain access to interlocking profiles  26 ,  32  and to thereby gain access to the contents of the reclosable bag  18 . 
     A fourth use of the fastener assembly  10  of the present invention is shown in FIGS. 9,  10  and  11 . In the front view of FIG. 9, a reclosable fastener assembly  10 , including a barrier arrangement, is attached by an oval barrier seal  22  to the front wall  14  of the reclosable bag. In this use, a strip of barrier tape  48  with a scored cut  42  is attached to the exterior wall  14  encompassed by the oval barrier seal. 
     On the inside of the front wall  14 , a closure flange  50  is sealed to the wall of the reclosable bag at tack seals  24  and  52 , with the tack seals  24  and  52  providing stability for the closure flange when an interlocking profile  26  is accessed. The interlocking profile  26  is interlockable with an interlocking profile  32  of a mating profile flange  34 . The mating profile flange  34  is sealed to the inside of the front wall  14  with the tack seal  36 , thereby providing an attachment area for the mating profile flange  34  when the interlocking profiles  26  and  32  are separated from one another. 
     To access the interlocking profiles  26  and  32 , the front wall  14  is provided with a line of weakness  40 . To access the line of weakness  40 , the strip of barrier tape  48  has a scored cut  42 . As shown in FIG. 11, when the line of weakness  40  and the scored cut  42  are opened, access is provided to the interlocking profiles  26  and  32 . The tack seals  36  and  52  secure the mating profile flange  34  and the closure flange  50  to the front wall so that the sole pathway  44  to the bag interior is through the profiles when the line of weakness  40  and the scored cut  42  are opened. The pathway  44  allows the user to gain access to interlocking profiles  26 ,  32  and to thereby gain access to the contents of the reclosable bag  18 . 
     A fifth use of the fastener assembly  10  of the present invention is shown in FIGS. 12,  13  and  14 . In the front view of FIG. 12, a barrier flange  20  is sealed by an oval barrier seal  22  to the outside of the front wall  14  with the barrier strip sealed to a flange  64  by a peelable seal  66 . The flange  64  is sealed to the outside of the front wall  14  by a section of the oval barrier seal  22  in alignment with the peelable seal  66 . The flange  64  is also sealed to the outside of the front wall  14  by a tack seal  24 . In the cross-sectional view of FIG. 13, the peelable seal  66  provides an opening section of the oval barrier seal  22 , allowing access to the interlocking profiles  26  and  32 . However, if the peelable seal  66  is torn open, the barrier flange  20  and the flange  64  protect the line of weakness  40  from also being torn open inadvertently. 
     As shown in FIG. 14, when the line of weakness  40 , the interlocking profiles  26  and  32  and the line of weakness  40  are opened, access is provided to the contents of the reclosable bag  18 . The oval barrier seal  22  secures the flanges  20  and  64  to the front wall so that the sole pathway  44  to the bag interior is through the profiles. The pathway  44  allows the user to gain access to the interlocking profiles  26 ,  32  and to thereby gain access to the contents of the reclosable bag  18 . 
     A sixth use of the fastener assembly  10  of the present invention is shown in FIGS. 15,  16 , and  17 . In the front view of FIG. 15, a reclosable fastener assembly  10 , including a barrier flange  20 , is attached to the front wall  14  by an oval barrier seal  22  of the reclosable bag  18  with a line of weakness  40  encompassed by the oval barrier seal. In the cross-sectional view of FIG. 16, the barrier flange  20  and a closure flange  50  are sealed by an oval barrier seal  22  to the front wall  14  of the reclosable bag  18 . The barrier flange  20  also seals to the closure flange  50  at a peelable seal  66 . The peelable seal  66  provides an opening section of the barrier arrangement, allowing access to interlocking profiles  26  and  32 . Even if the line of weakness  40  is torn open, the oval barrier seal  22  and the peelable seal  66  will still prevent air or liquid from entering or leaving the reclosable bag. 
     The interlocking profile  32  is integral to the barrier flange  20  and is interlockable with the interlocking profile  26  of the closure flange  50 . A tack seal  24  seals a lower end of the closure flange  50  to the front wall  14  of the reclosable bag. The tack seal  24  provides stability to the closure flange  50  when the interlocking profiles  26  and  32  are opened; however, a larger barrier seal  22  may be used in place of the tack seal  24 . As shown in FIG. 17, when the line of weakness  40  and the peelable seal  66  are opened, access is provided to the interlocking profiles  26  and  32 . The oval barrier seal  22  secures the barrier flange  20  and the closure flange  50  to the front wall so that the sole pathway  44  to the bag interior is through the profiles. The pathway  44  allows the user to gain access to interlocking profiles  26 ,  32  and to thereby gain access to the contents of the reclosable bag  18 . 
     A seventh use of the fastener assembly  10  is shown in FIGS. 15,  18 , and  19 . In the front view of FIG. 15, a reclosable fastener assembly  10  including a barrier flange  20  is attached to the front wall  14  by an oval barrier seal  22 , with a line of weakness  40  encompassed by the oval barrier seal. In the cross-sectional view of FIG. 18, a closure flange  50  is also sealed by an oval barrier seal  22  to the front wall  14  of the reclosable bag  18 . The barrier flange  20  also seals to the closure flange  50  at a peelable seal  66 . Even if the line of weakness  40  is torn open, the oval barrier seal  22  and the peelable seal  66  will still prevent air or liquid from entering or leaving the reclosable bag. 
     The peelable seal  66  provides an opening section of the barrier arrangement, allowing access to interlocking profiles  26  and  32 . The interlocking profile  26  of the closure flange  50  is interlockable with the interlocking profile  32  of the barrier flange  20 . In this use, the interlocking profile  32  is on a face of the extended barrier flange  20  opposite the face of the barrier flange that includes the peelable seal  66 . A tack  24  seals a lower end of the closure flange  50  to the front wall  14 , thereby providing stability to the closure flange  50  when the interlocking profiles  26  and  32  are opened; however, a larger barrier seal  22  may be used in place of the tack seal  24 . 
     As shown in FIG. 19, when the line of weakness  40  and the peelable seal  66  are opened, access is provided to the interlocking profiles  26  and  32 . The oval barrier seal  22  secures the barrier flange  20  and the closure flange  50  to the front wall so that the sole pathway  44  to the bag interior is through the profiles. The pathway  44  allows the user to gain access to interlocking profiles  26 ,  32  and to thereby gain access to the contents of the reclosable bag  18 . 
     A detail of the barrier flange  20  and the strip barrier tape  48  is shown in FIG.  20 . In the figure, the scored cut  42  is sliced through a sealant layer  80  and a strength layer  82 . The sealant layer is typically a linear low-density polyethylene material or similar materials known to those skilled in the art. The strength layer  82  is typically polyethylene terephthalate. By not fully slicing through the strength layer  82 , the integrity of the barrier flange  20  or the strip of barrier tape is maintained. A barrier layer  84  prevents moisture and oxygen from entering the reclosable bag. Another sealant layer  86  is provided to protect the layer of the barrier material and to provide a sealing surface. 
     Thus the several aforementioned objects and advantages are most effectively attained. Although preferred uses of the invention have been disclosed and described in detail herein, it should be understood that this invention is in no sense limited thereby and its scope is to be determined by that of the appended claims.