Reclosable bags having a tamper evident stepped member

Abstract
A plastic bag comprises opposing body panels fixedly connected to each other along a pair of sides and a bottom bridging the pair of sides. A reclosable zipper extending along a mouth portion formed opposite the sealed bottom of the plastic bag. The zipper is preferably free of graspable upper pull flanges in order to best accommodate a slider and inhibit operation of the zipper without the slider. The slider is mounted to the zipper for movement between a closed position and an open position. The zipper is closed while the slider is in the closed position. The zipper is opened in response to movement of the slider to the open position. To inhibit tampering with the contents of the bag, the bag includes a tamper-evident feature. In one set of embodiments, the tamper-evident feature initially maintains the slider in the closed position and allows the slider to move away from the closed position toward the open position in response to removing or breaking the tamper-evident feature. In another set of embodiments, the tamper-evident feature initially maintains a mouth portion of the plastic bag in a folded position and allows the mouth portion to be unfolded in response to removing or breaking the tamper-evident feature.
Description




FIELD OF THE INVENTION




The present invention generally relates to reclosable plastic bags and, more particularly, relates to a reclosable plastic bag having a tamper-evident feature. In one set of embodiments, the plastic bag has a zipper opened and closed using a slider mounted to the zipper, and the tamper-evident feature initially maintains the slider at a closed position on the zipper and allows the slider to move away from the closed position to an open position on the zipper in response to removing or breaking the tamper-evident feature. In another set of embodiments, the tamper-evident feature initially maintains a mouth portion of the plastic bag in a folded position and allows the mouth portion to be unfolded in response to removing or breaking the tamper-evident feature.




BACKGROUND OF THE INVENTION




Reclosable slider bags of the type disclosed in U.S. Pat. No. 5,067,208 include a zipper that is opened and closed by movement of a slider mounted to the zipper. Due to the ease of operating the slider, such slider bags have increased in popularity over the last few years. Heretofore, the primary market for slider bags has been consumers who purchase a package of empty slider bags and then fill the slider bags with products at home. However, with the increasing popularity of the slider bags, product manufacturers have become interested in packaging their food and nonfood products in slider bags for sale to consumers. The slider bags are a great convenience to the consumer who purchases these product-filled bags especially for products of the type where only a portion of the product is used at any given time. The product applications for which slider bags may be useful are virtually unlimited. The consumer may initially open the slider bag, use a portion of the product, and then easily reclose the slider bag. Due to the ease of using the slider bag, the slider bag is typically preferred over one-time openable bags, which are significantly more difficult to open and reclose. To open a one-time openable bag, the consumer may need to tear the bag open and may require a scissors or other tool to facilitate the opening process; to reclose the bag, the consumer typically must roll the top of the bag closed and may require an extra fastening mechanism such as a clip, tie, or tape to maintain the bag in the closed position.




A problem with plastic slider bags is that if such bags are to be prepackaged with a food or non-food product and then sold in a store, the contents of the plastic bags can easily be tampered with prior to purchase by the consumer. To inhibit such tampering, slider bags have been provided with tamper-evident features of the type disclosed in U.S. Pat. Nos. 5,669,715; 5,713,669; and 5,775,812. While such tamper-evident features are capable of providing tamper evidence upon opening the bag, bag manufacturers such as the assignee of the foregoing patents are continually striving to develop new bag features for improving the functionality of their bags.




SUMMARY OF THE INVENTION




To that end, the present invention provides a plastic bag comprising first and second opposing body panels fixedly connected to each other along a pair of sides and a bottom bridging the pair of sides. The bag is provided with a reclosable zipper extending along a mouth portion formed opposite the sealed bottom of the plastic bag. The zipper is preferably free of graspable upper pull flanges in order to best accommodate a slider and inhibit operation of the zipper without the slider. The slider is slidably mounted to the zipper for movement between a closed position and an open position. The zipper is closed while the slider is in the closed position. The zipper is opened in response to movement of the slider to the open position. The bag optionally includes end terminations at opposite ends of the zipper to prevent the slider from going past the ends of the zipper. To provide the plastic bag with tamper evidence, the bag includes a tamper-evident feature.




In one set of embodiments, the tamper-evident feature initially maintains the slider in the closed position and allows the slider to move away from the closed position toward the open position in response to removing or breaking the tamper-evident feature. The tamper-evident feature may take a variety of forms including for example: a removable cardboard, paper, or plastic member covering or adjacent to the slider in the closed position and adhered, stapled, friction fit, or connected in some other way to the bag to hold the member in place; a removable flexible member extending through a hole in the slider or through a hole in the zipper adjacent to the slider in the closed position; a removable stepped retaining element removably attached to one of the bag body panels near the closed position of the slider such that a shoulder of the slider is initially engaged to the stepped element and is disengaged therefrom upon removal of the stepped element; a latch connected to the end termination and releasably engaged to the slider in the closed position; a latch connected to the slider and releasably engaged to the end termination when the slider is in the closed position; and a removable U-shaped element extending through slots in the slider in the closed position and dug into the zipper.




The tamper-evident features noted above initially maintain the slider in the closed position. Therefore, prior to removing or breaking the tamper-evident feature, it is difficult to gain access to the interior of the bag because, in the absence of graspable upper flanges, the zipper is difficult to grasp and open by hand without the use of the slider. After the tamper-evident feature is removed or broken, the slider may be used to open the zipper and access the contents of the bag.




In another set of embodiments, the tamper-evident feature initially maintains the mouth portion of the plastic bag in a folded position and allows the mouth portion to be unfolded in response to removing or breaking the tamper-evident feature. The tamper-evident feature can be employed with both slider and sliderless bags and may take a variety of forms including for example: spot seals detachably sealing the sides of the folded mouth portion to the sides of the bag; spot seals detachably sealing the inner panel of the folded mouth portion to the adjacent bag panel; a removable flexible member passing through both the folded mouth portion and the adjacent unfolded portion of the bag; one or more stickers (adhesive strips) attaching the folded mouth portion to the adjacent unfolded portion of the bag; and combinations of the foregoing. If the flexible member or sticker is employed and the plastic bag includes a slider for operating the zipper, the flexible member or sticker may be strategically positioned to perform the dual function of maintaining the mouth portion in the folded position and preventing the slider from being moved away from the closed position until the flexible member or sticker is removed from the bag.




The tamper evident features of the present invention effectively inhibit tampering with contents of the bag to a degree that is especially useful for non-food and some food applications, where tamper-proof packaging is not required but tamper-resistant packaging is nonetheless desirable.











BRIEF DESCRIPTION OF THE DRAWINGS




Other object and advantages of the invention will become apparent upon reading the following detailed description and upon reference to the drawings in which:





FIG. 1

is an isometric view of a reclosable plastic slider bag having a slider mounted to a zipper in a closed position;





FIG. 2

is an isometric view of a mouth portion of the slider bag showing the slider moved away from the closed position so that the zipper is partially opened;





FIG. 3

is a sectional view taken generally along line


3





3


in

FIG. 1

;





FIG. 4



a


is a partial isometric view of a slider bag having a tamper-evident feature in the form of a removable adhesive label;





FIG. 4



b


is an enlarged isometric view of the slider bag showing the adhesive label in the process of being removed from the bag;





FIG. 4



c


is a sectional view taken generally along line


4




c—




4




c


in

FIG. 4



a;







FIG. 4



d


is a sectional view taken generally along line


4




d—




4




d


in

FIG. 4



b;







FIG. 5



a


is a partial isometric view of a slider bag having a tamper-evident feature in the form of a flexible member, such as a price tag pin, extending through a hole in the slider;





FIG. 5



b


is a partial isometric view of the slider bag showing the flexible member in the process of being cut away from the slider;





FIG. 5



c


is a sectional view taken generally along line


5




c—




5




c


in

FIG. 5



a;







FIG. 5



d


is a sectional view taken generally along line


5




d—




5




d


in

FIG. 5



b;







FIG. 6



a


is a partial isometric view of a slider bag having a tamper-evident feature in the form of flexible member, such as a price tag pin, extending through a hole in the zipper adjacent to the slider in the closed position;





FIG. 6



b


is a partial isometric view of the slider bag showing the flexible member in the process of being cut away from the zipper;





FIG. 6



c


is a sectional view taken generally along line


6




c—




6




c


in

FIG. 6



a;







FIG. 6



d


is a sectional view taken generally along line


6




d—




6




d


in

FIG. 6



b;







FIG. 7



a


is a partial isometric view of a slider bag having a tamper-evident feature in the form of a stepped retaining element attached to one of the bag body panels and engaging a shoulder of the slider in the closed position;





FIG. 7



b


is a partial isometric view of the slider bag showing the stepped retaining element in the process of being detached from the bag body panel and disengaged from the slider;





FIG. 7



c


is a sectional view taken generally along line


7




c—




7




c


in

FIG. 7



a;







FIG. 7



d


is a sectional view taken generally along line


7




d—




7




d


in

FIG. 7



b;







FIG. 7



e


is a partial isometric view of a slider bag having a tamper-evident feature in the form of a stepped retaining element integrally formed with a slider end stop and engaging a shoulder of the slider in the closed position;





FIG. 7



f


is a partial isometric view of the slider bag showing the stepped retaining element in the process of being detached from the slider end stop and disengaged from the slider;





FIG. 7



g


is a sectional view taken generally along line


7




g—




7




g


in

FIG. 7



e;







FIG. 7



h


is a sectional view taken generally along line


7




h—




7




h


in

FIG. 7



f;







FIG. 7



i


is a partial isometric view of a slider bag having a tamper-evident feature in the form of a stepped retaining element integrally formed with a slider end stop and engaging a shoulder of the slider in the closed position according to another embodiment of the invention;





FIG. 7



j


is a partial isometric view of the slider bag showing the stepped retaining element of

FIG. 7



i


in the process of being detached from the slider end stop and disengaged from the slider;





FIG. 7



k


is a sectional view taken generally along line


7




k—




7




k


in

FIG. 7



i;







FIG. 7



l


is a sectional view taken generally along line


7




l—




7




l


in

FIG. 7



j;







FIG. 8



a


is a partial isometric view of a slider bag having a tamper-evident feature in the form of shrink wrap encapsulating the slider in the closed position;





FIG. 8



b


is a partial isometric view of the slider bag showing the shrink wrap in the process of being removed from the bag;





FIG. 8



c


is a sectional view taken generally along line


8




c—




8




c


in

FIG. 8



a;







FIG. 8



d


is a sectional view taken generally along line


8




d—




8




d


in

FIG. 8



b;







FIG. 9



a


is a partial isometric view of a slider bag having a tamper-evident feature in the form of a plastic sleeve covering at least a portion of the slider in the closed position;





FIG. 9



b


is a partial isometric view of the slider bag showing the plastic sleeve in the process of being removed from the bag;





FIG. 9



c


is a sectional view taken generally along line


9




c—




9




c


in

FIG. 9



a,







FIG. 9



d


is a sectional view taken generally along line


9




d—




9




d


in

FIG. 9



b;







FIG. 10



a


is a partial isometric view of a slider bag having a tamper-evident feature in the form of an extruded friction fit plastic sleeve located adjacent to the slider in the closed position;





FIG. 10



b


is a partial isometric view of the slider bag showing the plastic sleeve in the process of being removed from the bag;





FIG. 10



c


is a sectional view taken generally along line


10




c—




10




c


in

FIG. 10



a;







FIG. 10



d


is a sectional view taken generally along line


10




d—




10




d


in

FIG. 10



b;







FIG. 11



a


is a partial isometric view of a slider bag having a tamper-evident feature in the form of a cardboard, paper, plastic, or foil strip stapled to the bag adjacent to the slider in the closed position;





FIG. 11



b


is a partial isometric view of the slider bag showing the stapled strip in the process of being removed from the bag;





FIG. 11



c


is a sectional view taken generally along line


11




c—




11




c


in

FIG. 11



a;







FIG. 11



d


is a sectional view taken generally along line


11




d—




11




d


in

FIG. 11



b;







FIG. 12



a


is a partial isometric view of a slider bag having a tamper-evident feature in the form of a plastic tab located adjacent to the slider in the closed position, and including a pair of tab panels detachably connected to and extending upward from respective bag body panels and attached to each other above the zipper;





FIG. 12



b


is a partial isometric view of the slider bag showing the plastic tab in the process of being removed from the bag;





FIG. 12



c


is a sectional view taken generally along line


12




c—




12




c


in

FIG. 12



a;







FIG. 12



d


is a sectional view taken generally along line


12




d—




12




d


in

FIG. 12



b;







FIG. 13



a


is a partial isometric view of a slider bag having a tamper-evident feature in the form of a latch extending from a slider end stop and releasably engaged to the slider in the closed position;





FIG. 13



b


is a partial isometric view of the slider bag showing the latch in the process of being disengaged from the slider.





FIG. 13



c


is a sectional view taken generally along line


13




c—




13




c


in

FIG. 13



a;







FIG. 13



d


is a sectional view taken generally along line


13




d—




13




d


in

FIG. 13



b;







FIG. 14



a


is a partial isometric view of a slider bag having a tamper-evident feature in the form of a latch extending from a slider end stop and engaged to the slider in the closed position;





FIG. 14



b


is a partial isometric view of the slider bag showing the latch in the process of being broken to release the slider from the end stop;





FIG. 14



c


is a sectional view taken generally along line


14




c—




14




c


in

FIG. 14



a;







FIG. 14



d


is a sectional view taken generally along line


14




d—




14




d


in

FIG. 14



b;







FIG. 15



a


is a partial isometric view of a slider bag having a tamper-evident feature in the form of a latch extending from the slider in the closed position and engaged to the slider end stop;





FIG. 15



b


is a partial isometric view of the slider bag showing the latch in the process of being broken to release the slider from the end stop;





FIG. 15



c


is a sectional view taken generally along line


15




c—




15




c


in

FIG. 15



a;







FIG. 15



d


is a sectional view taken generally along line


15




d—




15




d


in

FIG. 15



b;







FIG. 16



a


is a partial isometric view of a slider bag having a tamper-evident feature in the form of a U-shaped element extending through slots in the slider in the closed position and dug into the zipper;





FIG. 16



b


is a partial isometric view of the slider bag showing the U-shaped element in the process of being disengaged from the zipper and removed from the slider;





FIG. 16



c


is a sectional view taken generally along line


16




c—




16




c


in

FIG. 16



a;







FIG. 16



d


is a sectional view taken generally along line


16




d—




16




d


in

FIG. 16



b;







FIG. 17



a


is an isometric view of a slider bag having a tamper-evident feature created by folding over the mouth portion of the bag and detachably connecting the folded-over mouth portion to the sides of the bag;





FIG. 17



b


is a partial isometric view of the slider bag showing one of the side seals attaching the folded-over mouth portion to the sides of the bag;





FIG. 17



c


is a partial isometric view of the slider bag after the side seals have been broken to allow the mouth portion to be unfolded;





FIG. 18

is an isometric view of a slider bag having a tamper-evident feature created by folding over the mouth portion of the bag and securing the folded-over mouth portion with a price tag pin and a side seal;





FIG. 19



a


is an isometric view of a slider bag having a tamper-evident feature created by folding over the mouth portion of the bag and detachably sealing the inner panel of the folded-over mouth portion to the adjacent bag panel;





FIG. 19



b


is a section view taken generally along line


19




b—




19




b


in

FIG.19



a;







FIG. 20



a


is an isometric view of a slider bag having a tamper-evident feature created by folding over the mouth portion of the bag and securing the folded-over mouth portion with partially removable stickers; and





FIG. 20



b


is an isometric view of the slider bag in

FIG. 20



a


after the stickers have been partially removed to allow the mouth portion to be unfolded.











While the invention is susceptible to various modifications and alternative forms, a specific embodiment thereof has been shown by way of example in the drawings 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.




DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS




Turning now to the drawings,

FIG. 1

depicts a reclosable plastic slider bag


10


comprising first and second opposing body panels


12


and


14


fixedly connected to each other along a pair of sides


16


and


18


and a bottom


20


bridging the pair of sides


16


and


18


. The bag is provided with a reclosable zipper


22


extending along a mouth portion formed opposite the closed bottom


20


of the plastic bag.




Referring to

FIG. 3

, the zipper


22


includes a male track and a female track. The male track includes a male profile


24


and a first depending fin or flange


26


extending downward from the male profile


24


. Likewise, the female track includes a female profile


28


and a second depending fin or flange


30


extending downward from the female profile


28


. The first and second fins


26


and


30


are thermally fused to inner surfaces of the respective first and second body panels


12


and


14


. Alternatively, the zipper


22


may be extruded with the body panels


12


and


14


such that the first fin


26


is integrally formed with the first body panel


12


and the second fin


30


is integrally formed with the second body panel


14


. To provide a hermetic seal for the contents of the bag, the first and second fins


26


and


30


may be joined to each other at their lowermost ends along a line of weakness to effectively create a single tamper-evident continuous fin. If the fins are joined to each other, they must be separated from each other along the line of weakness in order to gain access to the contents of the bag. Further information concerning the joined fins may be obtained from U.S. application Ser. No. 08/950,535 filed Oct. 15, 1997 and entitled “Reclosable Fastener Strip With Tamper Evident Feature,” which is incorporated herein by reference in its entirety.




To assist in opening the plastic bag, a slider


32


is slidably mounted to the zipper


22


for movement between a closed position and an open position. In the closed position of the slider


32


shown in

FIG. 1

, the male and female profiles


24


and


28


are interlocked with each other. Movement of the slider


32


from the closed position in

FIG. 1

toward the open position (see

FIG. 2

) disengages the male and female profiles


24


and


28


from each other and allows a user to gain access to the interior of the plastic bag. The zipper


22


is preferably free of graspable upper pull flanges extending upward from the profiles


24


and


28


in order to facilitate mounting and movement of the slider


32


along the zipper


22


. Also, the absence of such upper pull flanges inhibits a user from opening and closing the zipper


22


without the use of the slider


32


.




Opposite ends of the zipper


22


are provided with end termination clamps


34


. Each end clamp


34


includes a strap member that wraps over the top of the zipper


22


. To mount the strap to the zipper


22


, one end of the strap is provided with a rivet-like member that is adapted to penetrate through the bag material and into a cooperating opening at the other end of the strap. The end clamps


34


perform the dual function of stops for the ends of the zipper


22


to prevent the slider


32


from going past the end of the zipper


22


and, in addition, they hold the male and female profiles


24


and


28


together to resist stresses applied to the profiles during normal use of the plastic bag. Further details concerning the construction and operation of the slider


32


and the end clamps


34


may be obtained from U.S. Pat. No. 5,067,208 to Herrington, Jr. et al., which is incorporated herein by reference in its entirety. The end terminations


34


are merely illustrative and may take other forms known in the art, such as those disclosed in U.S. Pat. Nos. 5,482,375; 5,448,807; 5,442,837; 5,405,478; 5,161,286; 5,131,121; and 5,088,971 and in U.S. application Ser. No. 08/698,923 filed Aug. 16, 1996 and entitled “End Posts for Plastic Zipper,” all of which are incorporated herein by reference in their entireties.




To provide the plastic bag with tamper evidence, the bag includes a tamper-evident feature. In one set of embodiments depicted in

FIGS. 4



a-d


through


16




a-d,


the tamper-evident feature initially maintains the slider


32


in the closed position (

FIG. 1

) and allows the slider


32


to move away from the closed position toward the open position (see

FIG. 2

) in response to removing or breaking the tamper-evident feature. Prior to removing or breaking the tamper evident feature, it is difficult to gain access to the interior of the bag because, in the absence of graspable upper flanges, the zipper


22


is difficult to grasp and open by hand without the use of the slider


32


. The tamper-evident feature may take a variety forms which are discussed below in connection with

FIGS. 4



a-d


through


16




a-d.






Referring to

FIGS. 4



a-d,


there is shown a tamper-evident feature in the form of a partially removable adhesive label


40


adjacent to the narrow closing end


32




a


of the slider


32


when the slider


32


is in the closed position on the zipper


22


. Opposing end sections


40




a


and


40




b


of the label


40


are permanently adhered to outer surfaces of the opposing bag body panels


12


and


14


, while a middle portion


40




c


of the label


40


is detachably connected to these end sections


40




a


and


40




b


along respective perforation lines. One or both ends of each perforation line may be provided with a notch to help initiate tearing along the perforation line. The middle portion


40




c


is either not adhered to the bag or is peelably adhered to the bag. Prior to removal, the label


40


extends over the zipper


22


as shown in

FIGS. 4



a


and


4




c


so as to obstruct movement of the slider


32


away from the closed position. To allow movement of the slider


32


and thereby gain access to the interior of the bag, a user grasps the portion


40




c


of the label


40


extending over the zipper


22


and detaches this portion


40




c


from the end sections


40




a


and


40




b


as shown in

FIGS. 4



b


and


4




d.


The end sections


40




a


and


40




b


remaining on the bag provide evidence of tampering. In an alternative embodiment, the label


40


does not include the perforation lines, but rather is removed using a cutting tool such as a scissors or knife.




Referring to

FIGS. 5



a-d,


there is shown a tamper-evident feature in the form of a flexible member, such as a conventional plastic price tag pin


50


, extending through a hole


52


in the slider


32


and through the zipper


22


when the slider


32


is in the closed position on the zipper


22


. The price tag pin


50


includes a pair of stops


54


and


56


at its opposing ends to keep the pin


50


in place. Since the price tag pin


50


is anchored to the zipper


22


, the slider


32


cannot be moved away from the closed position until the price tag pin


50


is clipped off the bag as shown in

FIGS. 5



b


and


5




d.


As shown in

FIGS. 6



a-d,


the price tag pin


50


may alternatively be anchored to the zipper


22


adjacent to the closing end


32




a


of the slider


32


when the slider


32


is in the closed position on the zipper


22


. The zipper


22


includes the profiles


24


and


28


and the fins


26


and


30


extending downward from the respective profiles


24


and


28


. The price tag pin


50


may extend through a hole in either the profiles


24


and


28


(not shown) or the fins


26


and


30


as shown in

FIG. 6



c.


The pin


50


may extend through both the fins and the opposing body panels (as shown) or just the fins. Prior to removal of the pin


50


, the pin


50


blocks movement of the slider


32


away from the closed position.




Referring to

FIGS. 7



a-d,


there is shown a tamper-evident feature in the form of a removable stepped retaining element


70


removably attached to the bag body panel


12


just below the zipper


22


at the closed position of the slider. The stepped element


70


may be attached to the bag body panel


12


by a peel seal or other weak adhesive that allows the stepped element


70


to be peeled or pried away as shown in

FIGS. 7



b


and


7




d.


The stepped element


70


forms one or more steps


72


having respective sloped surfaces. The sloped surfaces of the respective steps


72


may be inclined such that each step


72


gradually increases in thickness in a direction approaching the end stop


34


. To engage one of the steps


72


, the slider


32


includes at least one inwardly extending shoulder


73


that is contoured to form a protrusion or bump


74


. The protrusion


74


may be located anywhere along the shoulder


73


. Further details concerning the contoured shoulder


73


may be obtained from U.S. application Serial No. 08/938,047 filed Apr. 26, 1997, entitled “High-Strength Slider for a Reclosable Bag,” and incorporated herein by reference in its entirety. When the slider


32


is in the closed position, the protrusion


74


on the slider shoulder


73


engages a raised edge


76


(

FIG. 7



a


) on one of the steps


72


.




To create the tamper-evident feature in

FIGS. 7



a-d,


the stepped element


70


is preferably first adhered to the bag body panel


12


. Subsequently, the slider


32


may be engaged to the stepped element


70


using a couple of techniques. In one technique, if the slider


32


is of the wing-lock type disclosed in U.S. Pat. No. 5,067,208, the slider


32


may be installed on the zipper


22


at a location immediately above the stepped element


70


. The wing-lock slider


32


includes a pair of hinged wings


78


and


79


that, prior to installing the slider


32


on the zipper


22


, are spread away from each other in an open position (not shown). The wing


78


forms the shoulder


73


having the protrusion


74


. The slider


32


is initially mounted to the zipper


22


above the stopped element with the wings


78


and


79


in the open or spread position, and then the wings


78


and


79


are rotated downward and latched in a closed position depicted in

FIGS. 7



a-d.


As the wings


78


and


79


are latched in the closed position, the protrusion


74


engages the edge


76


of one of the steps


72


. In another technique, the slider


32


is installed on the zipper


22


at a location away from the stepped element


70


. The slider


32


is then moved along the zipper


22


to the closed position. When approaching the closed position, the slider shoulder


73


is forced over the stepped element


70


until the protrusion


74


engages the edge


76


of one of the steps


72


.




To remove the stepped element


70


and thereby allow movement of the slider


32


away from the closed position, a user grasps a tab


71


of the stepped element


70


and peels or pries the stepped element


70


away from the bag body panel


12


as shown in

FIGS. 7



b


and


7




d.






Referring to

FIGS. 7



e-h,


in an alternative embodiment a breakaway stepped element


70


′ is integrally formed with the end stop


34


and is detachably connected to the end stop


34


along a weakened area of connection


75


(

FIG. 7



e


). To remove the stepped element


70


′, the slider


32


is forced away from the closed position as shown in

FIG. 7



f


to break the weakened connection


75


. The detached stepped element


70


′ is then removed from beneath the slider


32


. To facilitate removal of the stepped element


70


′, a pull tab akin to the tab


71


in

FIGS. 7



a-d


may be provided. Instead of detaching the stepped element


70


′ from the end stop


34


by forcibly moving the slider


32


away from the end stop


34


, the stepped element


70


′ may alternatively be provided with a pull tab that is grasped and pulled by a user to first rupture the weakened connection


75


and then remove the detached stepped element


70


′ from beneath the slider


32


.

FIGS. 7



i-l


depict a further alternative embodiment of the invention where the sloped surfaces of the respective steps


72


′ of the breakaway stepped element


270


gradually increase in thickness. As shown in

FIGS. 7



i


and


7




j,


the breakaway stepped element


270


forms one or more steps


72


′ having respective sloped surfaces which are inclined such that each step


72


′ gradually increases in thickness in a direction approaching the end stop


34


. Similar to

FIGS. 7



e-h,


to remove the breakaway stepped element


270


, the slider


32


is forced away from the closed position as shown in

FIG. 7



j


to break the weakened connection


75


. The detached breakaway stepped element


270


is then removed from beneath the slider


32


.




Referring to

FIGS. 8



a-d,


there is shown a tamper-evident feature in the form of removable plastic shrink wrap


80


encapsulating the slider


32


when the slider


32


is in the closed position. The shrink wrap


80


is adhered or thermally fused to the bag body panels


12


and


14


. The shrink wrap


80


may additionally encapsulate the end stop


34


, in which case the shrink wrap


80


may only need to be attached to itself and not to the body panels in order to be held in place. Alternatively, the shrink wrap may be shrunk over the zipper


22


in front of the slider


32


. To allow the slider


32


to be moved away from the closed position, the shrink wrap


80


is torn or peeled away from the bag as shown in

FIGS. 8



b


and


8




d.


The shrink wrap


80


may be notched or perforated to facilitate its removal. Such perforations could be located along the top or sides of the shrink wrap


80


depending upon the manner in which it is desired that the shrink wrap


80


be torn away. It is contemplated that a portion of the shrink wrap


80


could remain attached to the bag body panels


12


and


14


for tamper evidence after most of the shrink wrap


80


is torn away, so long as the remaining portion does not interfere with the movement of the slider


32


.




Referring to

FIGS. 9



a-d,


there is shown a tamper-evident feature in the form of a rigid or flexible plastic sleeve


90


partially covering the slider


32


when the slider


32


is in the closed position. Alternatively, the sleeve


90


may be increased in length to cover the entire slider


32


. The sleeve


90


is either adhered or thermally fused to one or both of the bag body panels


12


and


14


as shown in

FIGS. 9



a


and


9




c


or attached to the end stop


34


(not shown). To allow the slider


32


to be moved away from the closed position, the plastic sleeve


90


is torn or peeled away from the bag as shown in

FIGS. 9



b


and


9




d.






Referring to

FIGS. 10



a-d,


in an alternative embodiment a plastic sleeve


100


is mounted over the zipper


22


adjacent to the closing end


32




a


of the slider


32


when the slider is in the closed position. The sleeve


100


may be adhered or thermally fused to the bag body panels


12


and


14


and, additionally or alternatively, may be releasably connected to the zipper


22


by a friction fit. Also, the sleeve


100


may extend along only a short portion of the length of the zipper


22


as shown, or may extend along substantially the entire length of the zipper


22


less the region of the zipper


22


occupied by the slider


32


. To achieve a strong friction fit between the sleeve


100


and the zipper


22


, the sleeve


100


is preferably extruded to have an inner profile conforming to an outer profile of the zipper


22


as shown in

FIG. 10



c.


When the sleeve


100


is mounted to the zipper


22


, the sleeve


100


obstructs movement of the slider


32


away from the closed position. To allow the slider


32


to be moved away from the closed position, the sleeve


100


is pried off the zipper


22


either by pulling the entire sleeve


100


upward off the zipper


22


(not shown) or, if the sleeve


100


is sufficiently flexible, by releasing and lifting one side of the sleeve


100


as shown in

FIGS. 10



b


and


10




d.






Referring to

FIGS. 11



a-d,


there is shown a tamper-evident feature in the form of a cardboard, paper, plastic, or foil strip


110


wrapped over the zipper


22


at a location adjacent to the closing end


32




a


of the slider


32


when the slider


32


is in the closed position. The strip


110


is stapled to the bag body panels


12


and


14


. To allow the slider


32


to be moved away from its closed position, the staple is removed from the strip


110


which is, in turn, removed from the bag.




Referring to

FIGS. 12



a-d,


there is shown a tamper-evident feature in the form of a plastic tab


120


located adjacent to the closing end


32




a


of the slider


32


when the slider is in the closed position. The plastic tab


120


includes a pair of tab panels


120




a


and


120




b


(

FIG. 12



c


) integrally formed with the respective bag body panels


12


and


14


and detachable therefrom along lines of weakness


122


(

FIG. 12



a


). The lines of weakness may be perforations, scores, thinned areas, or the like. The tab panels


120




a


and


120




b


extend upwardly above the zipper


22


and are adhered or thermally fused to each other above the zipper


22


. To allow the slider


32


to be moved away from its closed position, the tab panels


120




a


and


120




b


are grasped and pulled in a generally upward direction until they are broken away from the bag body panels


12


and


14


along the lines of weakness


122


as shown in

FIGS. 12



b


and


12




d.


It is contemplated that a single tab panel maybe used in place of the pair of tab panels


120




a


and


120




b.






Referring to

FIGS. 13



a-d,


there is shown a tamper-evident feature in the form of a latch


130


extending from the end stop


34


and releasably engaged to the slider


32


when the slider


32


is in the closed position. The illustrated latch


130


is connected to the end stop


34


along a one-time breakable hinge that biases the latch


130


toward the position depicted in

FIG. 13



a.


The latch


130


may extend along the side of the slider


32


as shown or, alternatively, may extend along the top wall of the slider


32


. As shown in

FIG. 13



a,


the latch


130


is shaped to extend about the exterior of the slider


32


and forms a distal hook


132


that engages the closing end


32




a


of the slider


32


. Alternatively, the slider


32


may be modified to include a protruding tab, and the latch


130


may be adapted to engage the protruding tab. To allow the slider


32


to be moved away from its closed position, the latch


130


is pivoted outward away from the slider


32


until the hook


132


disengages from the slider


32


as shown in

FIGS. 13



b


and


13




d.


The latch


130


is then torn away from the end stop


34


and discarded.




Referring to

FIGS. 14



a-d,


there is shown a tamper-evident feature in the form of an arrow-shaped latch


140


extending from the slider end stop


34


and engaged to the slider


32


when the slider


32


is in the closed position. The latch


140


is integrally formed with the end stop


34


, and the slider


32


is initially injection molded with an elongated cavity


142


having a shape generally corresponding to the shape of the latch


140


. The transverse dimension of the cavity is slightly greater than the transverse dimension of the latch


140


. To “activate” the tamper-evident feature, the slider


32


is moved to the closed position such that the latch


140


is inserted into the cavity


142


and the barb-like head


144


of the latch


140


snappingly engages a shoulder


146


deep within the cavity


142


. The latch head


144


is sufficiently flexible to allow the latch


140


to be inserted in the cavity


142


and, yet, its barb-like shape prevents the latch


140


from subsequently being extracted from the cavity


142


. The installed latch


140


is depicted in

FIGS. 14



a


and


14




c.


To allow the slider


32


to be moved away from its closed position, the slider


32


is simply grasped and moved away from the closed position with sufficient force to break the latch


140


away from the end stop


34


as shown in

FIGS. 14



b


and


14




d.


The latch


140


remains captured within the cavity


142


of the slider


32


.




As shown in

FIGS. 15



a-d,


an arrow-shaped latch


150


may alternatively extend from the slider


32


and be engaged to the end stop


34


. The latch


150


is inserted into a cavity


152


within the end stop


34


and snappingly engaged to a shoulder


154


within the cavity


152


. In response to forcing the slider


32


away from its closed position, the latch


150


is broken away from the slider


32


and remains captured within the cavity


152


as shown in

FIGS. 15



b


and


15




d.






Referring to

FIGS. 16



a-d,


there is shown a tamper-evident feature in the form of a U-shaped rigid or semi-rigid retaining element


160


extending through slots


162


in the slider


32


and dug into the zipper


22


(see

FIG. 16



c


) when the slider


32


is in the closed position. The U-shaped element


160


may be composed of metal or plastic. The slider


32


includes a transverse member


163


and a pair of side walls


164


and


165


extending downward from opposing longitudinal sides of the transverse member


163


. The transverse member


163


rides along the upper portion of the zipper


22


. The side wall


164


includes a leg


166


and a hinged wing


167


. After the slider


32


is installed on the zipper


22


, the wing


167


encompasses and is latched to the leg


166


. The side wall


165


includes a leg and a hinged wing akin to the respective leg


166


and wing


167


of the side wall


164


. The slots


162


are formed by a small gap separating the wing


167




20


from the leg


166


. Further details concerning the construction of the slider


32


may be obtained from U.S. application Ser. No. 08/938,047 filed Apr. 26, 1997, entitled “High-Strength Slider for a Reclosable Bag,” and already incorporated herein by reference in its entirety.




An advantage of the tamper-evident feature in

FIGS. 16



a-d


is that a slider bag utilizing the slider


32


constructed as described above is already suitable for receiving the U-shaped element


160


. No special features need to be added to the slider


32


. Therefore, such a slider bag may be retrofitted with the U-shaped element


160


to provide the bag with a degree of tamper evidence. To allow the slider


32


to be moved away from the closed position, the U-shaped element


160


is disengaged from the zipper


22


and removed from the slider


32


. To facilitate such removal of the U-shaped element, a prying tool such as a screwdriver may be inserted between the slider leg


166


and the U-shaped element


160


. In an alternative embodiment, the U-shaped element


160


is replaced with a rigid element that passes through only a single slot or hole in the slider


32


and digs into the zipper


22


. This rigid element is preferably provided with some sort of handle that can be manipulated by hand or with a tool to facilitate removal of the rigid element from the slider


32


.




In another set of embodiments illustrated in

FIGS. 17



a-c


through

FIGS. 20



a-b,


the tamper-evident feature initially maintains a mouth portion of the plastic bag in a folded position and allows the mouth portion to be unfolded in response to removing or breaking the tamper-evident feature. The tamper-evident feature can be employed with both slider and sliderless bags.




Referring to

FIGS. 17



a-c.


there is shown a tamper-evident feature created by folding over the mouth portion


170


of the bag and detachably sealing the folded-over mouth portion


170


to the sides


16


and


18


of the bag along side spot seals


172


and


174


. With the bag in the folded position, as shown in

FIGS. 17



a


and


17




b,


access to the interior of the bag is restricted because even if the slider


32


is moved from the closed position to the open position, one would have difficulty getting past the fold


176


after entering the bag. In addition to providing tamper evidence, the folded-over mouth portion


170


provides a convenient handle for carrying the bag especially when the seals for attaching the folded-over mouth portion


170


are located along the sides


16


and


18


. To gain access to the contents of the bag, the side seals


172


and


174


are ruptured to allow the mouth portion


170


to be unfolded as shown in

FIG. 17



c.






As shown in

FIGS. 18

,


19




a-b,


and


20




a-b,


the folded-over mouth portion


170


may alternatively be secured in the folded position by other means. For example, in

FIG. 18

, the folded-over mouth portion


170


is held in the folded position by the combination of a spot seal


174


along the side


18


and a flexible member, such as a price tag pin


180


, passing through both the zipper


22


and the adjacent unfolded bag portion near the side


16


. The price tag pin


180


performs the dual function of maintaining the mouth portion


170


in the folded position and preventing the slider


32


from being moved away from the closed position until the pin


180


is removed from the bag. The embodiment in

FIG. 18

may be modified to eliminate the spot seal


174


and provide either a single price tag pin approximately midway between the sides


16


and


18


or a pair of price tag pins near the respective sides


16


and


18


. Any price tag pin near the side


16


is preferably disposed adjacent to or through the slider


32


along the zipper


22


to prevent the slider


32


from being moved away from the closed position until the pin is removed from the bag.




In

FIGS. 19



a-b,


the folded-over mouth portion


170


is secured in the folded position by one or more spot seals


190


and


192


detachably sealing the bag panel


12


to itself. The spot seals may, for example, be peelable seals or “dirty” seals. The portion of the bag panel


12


on the mouth portion


170


is adhered to the adjacent unfolded portion of the bag panel


12


. The spot seals


190


and


192


may, if desired, be strategically positioned to create a handle for carrying the bag.




In

FIGS. 20



a-b,


the folded-over mouth portion


170


is secured in the folded position by one or more partially removable stickers (adhesive strip) or pressure-sensitive labels


200


that attach the mouth portion


170


to the adjacent unfolded portion of the bag panel


12


. One of the stickers


200


may be positioned adjacent to or over the slider


32


along the zipper


22


to prevent the slider


32


from being moved away from the closed position until the sticker is removed from the bag. A middle portion of each sticker


200


is torn away to allow the mouth portion


170


to be unfolded, while end portions of each sticker


200


remain permanently attached to the bag to provide evidence of tampering.




Each tamper-evident feature described above makes it difficult to gain access to the interior of the bag prior to removing or breaking the tamper-evident feature. In the absence of graspable upper flanges, the zipper


22


is difficult to grasp and open by hand without the use of the slider


32


. Therefore, with respect to those tamper-evident features that prevent movement of the slider


32


away from the closed position, such tamper-evident features effectively inhibit tampering with the contents of the bag to a degree that is especially useful for non-food and some food applications, where tamper-proof packaging is not required but tamper-resistant packaging is nonetheless desirable. For example, the tamper-evident features in

FIGS. 4



a-d,




8




a-d,




9




a-d,




10




a-d,




11




a-d,


and


12




a-d


are advantageous in that tamper resistance is accomplished by using a removable cardboard, paper, plastic, or foil member covering or adjacent to the slider in the closed position and adhered, stapled, friction fit, or connected in some other way to the bag to hold the member in place. If the member is composed of plastic, the plastic may be a polymer or copolymer comprised of polyethylene-based polymers, polystyrene, polypropylene, nylon, polycarbonate, or other similar materials. The polyethylene-based polymers may include low density polyethylene, linear low density polyethylene, metallocene, ethylene vinyl acetate, or other similar materials. The shrink wrap


80


in

FIGS. 8



a-d


is preferably composed of conventional low density polyethylene. The plastic tab


120


in

FIGS. 12



a-d


is formed from the same material as the bag body panels


12


and


14


because the detachable tab panels


120




a


and


120




b


are integrally formed with the respective bag body panels


12


and


14


.




Further, the tamper-evident features in

FIGS. 5



a-d


and


6




a-d


are advantageous in that tamper resistance is accomplished by using a conventional price tag pin anchored to at least the zipper


22


(

FIGS. 5



a-d


and


6




a-d


) and optionally anchored to the slider


32


as well (

FIGS. 5



a-d


) so as to obstruct movement of the slider


32


away from its closed position. The tamper-evident features in

FIGS. 13



a-d,




14




a-d,


and


15




a-d


are advantageous in that tamper resistance is accomplished by using a movable (

FIGS. 13



a-d


) or breakable (

FIGS. 14



a-d


and


15




a-d


) latch releasably coupling the slider


32


to the end stop


34


. The stepped element in

FIGS. 7



a-h


is likewise effective at providing resistance to tampering with the contents of the slider bag.




Unlike the tamper-evident features in

FIGS. 4



a-d


through


16




a-d,


the tamper-evident features in

FIGS. 17



a-c,




18


,


19




a-b,


and


20




a-b


do not rely upon preventing movement of the slider


32


away from its closed position. Rather, the tamper-evident features in

FIGS. 17



a-c,




18


,


19




a-b,


and


20




a-b


rely upon securing the bag mouth in a folded position and would still be effective in the absence of the slider


32


and the zipper


22


. Therefore, unlike the other tamper-evident features, the tamper-evident features in

FIGS. 17



a-c,




18


,


19




a-b,


and


20




a-b


may be applied to virtually any type of bag. If, however, a slider bag is employed, it is contemplated that the tamper-evident features of

FIGS. 4



a-d


through


16




a-d


can be combined with the tamper-evident features in

FIGS. 17



a-c,




18


,


19




a-b,


and


20




a-b


so as to both secure the bag mouth in a folded position and prevent movement of the slider away from its closed position until the appropriate tamper-evident feature is broken or removed. Examples of bags combining multiple tamper-evident features is illustrated in

FIGS. 18 and 20



a-b.






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
  • 1. A slider bag, comprising:first and second opposing body panels fixedly connected to each other along a pair of sides and a bottom bridging said pair of sides; a reclosable zipper extending along a mouth formed opposite said bottom; a slider slidably mounted to said zipper for movement between a closed position and an open position, said zipper being closed while said slider is in said closed position, said zipper being opened in response to movement of said slider to said open position, said slider including a shoulder riding along said first body panel as said slider is moved between said closed and open positions; and a stationary stepped member disposed adjacent to said first body panel and including at least one step, said shoulder being engaged to said step when said slider is initially in said closed position so as to initially prevent movement of said slider away from said closed position, said slider being allowed to move away from said closed position in response to removal of said stepped member from the bag.
  • 2. The bag of claim 1, further including an end termination mounted to said zipper and disposed adjacent to said closed position of said slider, said end termination stopping said slider at said closed position when said slider is moved from said open position to said closed position, and wherein said stepped member is detachably connected to said end termination.
  • 3. The bag of claim 2, wherein said stepped member is integrally formed with said end termination.
  • 4. The bag of claim 1, wherein said stepped member includes a plurality of steps having respective sloped surfaces, said sloped surfaces being inclined such that each of said plurality of steps gradually increases in thickness in a direction extending away from said open position of said slider.
  • 5. The bag of claim 1, wherein said shoulder includes a protrusion, said protrusion from said shoulder being engaged to said step when said slider is initially in said closed position so as initially prevent movement of said slider away from said closed position.
  • 6. The bag of claim 1, wherein said stepped member is located beneath said slider.
  • 7. The bag of claim 2, wherein said stepped member is detachably connected to said end termination along a weakened area of connection.
  • 8. The bag of claim 1, wherein said stepped member is adapted to be removed by forcing said slider away from said closed position so as to break a weakened area of connection between an end termination mounted to said zipper and disposed adjacent to said closed position of said slider, said end termination stopping said slider at said closed position when said slider is moved from said open position to said closed position.
  • 9. The bag of claim 8, wherein said stepped member is integrally formed with said end termination.
  • 10. The bag of claim 2, wherein said stepped member includes a plurality of steps having respective sloped surfaces, said sloped surfaces being inclined such that each of said plurality of steps gradually increases in thickness in a direction extending away from said open position of said slider.
  • 11. The bag of claim 1, wherein said stepped member is a breakaway stepped member which is detachably connected to an end termination mounted to said zipper and disposed adjacent to said closed position of said slider, said end termination stopping said slider at said closed position when said slider is moved from said open position to said closed position.
  • 12. The bag of claim 1, wherein said stepped member includes a pull tab adapted to remove said stepped member from said slider.
  • 13. The bag of claim 12, wherein said pull tab is adapted to be pulled so as to rupture a weakened area of connection between said stepped member and an end termination mounted to said zipper and disposed adjacent to said closed position of said slider.
  • 14. A slider bag, comprising:first and second opposing body panels fixedly connected to each other along a pair of sides and a bottom bridging said pair of sides; a reclosable zipper extending along a mouth formed opposite said bottom; a slider slidably mounted to said zipper for movement between a closed position and an open position, said zipper being closed while said slider is in said closed position, said zipper being opened in response to movement of said slider to said open position, said slider including a shoulder riding along said first body panel as said slider is moved between said closed and open positions; an end termination mounted to said zipper and disposed adjacent to said closed position of said slider, said end termination stopping said slider at said closed position when said slider is moved from said open position to said closed position; and a stationary stepped member disposed adjacent to said first body panel and including at least one step, said shoulder being engaged to said step when said slider is initially in said closed position so as to initially prevent movement of said slider away from said closed position, said slider being allowed to move away from said closed position in response to removal of said stepped member from said bag, said stepped member being detachably connected to said end termination.
  • 15. The bag of claim 14, wherein said stepped member is integrally formed with said end termination.
  • 16. The bag of claim 14, wherein said stepped member includes a plurality of steps having respective sloped surfaces, said sloped surfaces being inclined such that each of said plurality of steps gradually increases in thickness in a direction extending away from said open position of said slider.
  • 17. The bag of claim 14, wherein said shoulder includes a protrusion, said protrusion from said shoulder being engaged to said step when said slider is initially in said closed position so as initially prevent movement of said slider away from said closed position.
  • 18. The bag of claim 14, wherein said stepped member is located beneath said slider.
  • 19. The bag of claim 14, wherein said stepped member is detachably connected to said end termination along a weakened area of connection.
  • 20. The bag of claim 14, wherein said stepped member includes a pull tab adapted to remove said stepped member from said slider.
  • 21. The bag of claim 20, wherein said pull tab is adapted to be pulled so as to rupture a weakened area of connection between said stepped member and said end termination.
CROSS REFERENCE TO RELATED APPLICATIONS

This application is a divisional of U.S. Ser. No. 09/309,465, filed on May 11, 1999, now U.S. Pat. No. 6,286,488.

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