Transverse direction zipper tape

Abstract

The reclosable container or bag (100) includes a zipper tape (18) with interlocking profiles (14, 16) of a zipper (12). First and second lines of perforation (28, 30) are formed parallel to and between the interlocking profiles (14, 16). Furthermore, the zipper tape (18) is looped so as to align the first and second lines of perforation (28, 30) with each other thereby forming a perforated cap structure (10). An additional layer of material (24) is formed to cover the first and second lines of perforation (28, 30) to maintain a hermetic seal prior to tearing of the first and second lines of perforation (28, 30). Typically, a notch (120, 122) is formed in at least one of the crush areas (116, 118) on the end of the zipper tape (18) to direct the user's tearing force to the lines of perforation (28, 30) thereby providing access to the zipper (12) and providing subsequent evidence of prior opening of reclosable container or bag (100).

Description

BACKGROUND OF THE INVENTION

[0001] 1. Field of the Invention

[0002] The present invention relates to a transverse direction zipper tape for a reclosable container, such as a plastic bag. More specifically, the present invention relates to the attachment of a perforated cap zipper tape to a web in a transverse direction.

[0003] 2. Description of the Prior Art

[0004] In the prior art, tamper-evident, hermetic reclosable containers, such as plastic bags, are known. Typical examples of this prior art are U.S. Pat. No. 5,023,122 entitled “Easy Open Bag Structure” issued to Boeckmann et al. on Jun. 11, 1991 and U.S. Pat. No. 5,100,246 entitled “Pull Bead and Guide Rails for Easy Open Flexible Containers” issued to La Pierre et al. on Mar. 31, 1992. While this art is well-developed, improvements in various aspects are sought.

SUMMARY OF THE INVENTION

[0005] The present invention is a method and apparatus relating to a reclosable container, such as a plastic bag, with a segment of perforated cap zipper tape applied to the web in a transverse direction. This provides a hermetic, tamper-evident, easy opening package, even for polyethylene packages that would normally require the consumer to use scissors to open the package. The cap or base is typically made from a material that will keep the inner flanges from sealing together from the main seal but still allow the zipper segment end seals to fuse together. Alternatively, the thickness of the cap or base can be used to provide enough insulation from the main seal.

[0006] More particularly, the perforated cap zipper tape provides a loop between the flanges of two zipper profiles and perforations are provided within the loop, so that the loop, which forms a header, can be removed from the package to provide access to the package and to provide evidence of prior opening.

BRIEF DESCRIPTION OF THE DRAWINGS

[0007] Further objects and advantages of the invention will become apparent from the following description and claims, and from the accompanying drawings, wherein:

[0008] FIG. 1 is a perspective view of the perforated cap and related structure of the present invention.

[0009] FIG. 2 is a plan view of the formed bag of the present invention.

[0010] FIG. 3 is a plan view of a first embodiment of the end seals of the formed bag of the present invention.

[0011] FIG. 4 is a plan view of a second embodiment of the end seals of the formed bag of the present invention.

[0012] FIG. 5 is a plan view of a third embodiment of the end seals of the formed bag of the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0013] Referring now to the drawings in detail wherein like numerals refer to like elements throughout the several views, one sees that FIG. 1 is a perspective view of perforated cap structure 10 of the present invention.

[0014] Zipper 12 includes male interlocking profile 14 and female interlocking profile 16. Zipper tape 18 is secured to both male and female interlocking profiles 14, 16 thereby forming extended tack flange 20 below female interlocking profile 16, extended tack flange 21 below male interlocking profile 14, and loop 22 between interlocking profiles 14, 16. Loop 22 of zipper tape 18 further includes interior reinforcing layer 24 thereby forming a “cap structure”. The upper interior apex of loop 22 further typically includes stiffener 26 therewithin. Moreover, a first line of perforation 28 (or a similarly weakened area) is formed through zipper tape 18 between the apex of loop 22 and male interlocking profile 14. Similarly, a second line of perforation 30 (or a similarly weakened area) is formed through zipper tape 18 and between the apex of loop 22 and female interlocking portion 16. In order to maintain a hermetic seal prior to the tearing of first and second lines of perforation 28, 30, typically the internal reinforcing layer 24 is not perforated. However, first and second lines of perforation 28, 30 can extend through internal reinforcing layer 24 if the hermetic quality of the package is not necessary. As illustrated in FIG. 1, first and second lines of perforation 28, 30 allow the upper portion or header 32 of loop 28 to be removed. When perforated cap structure 10 is sealed to a web to form a reclosable container as shown in FIG. 2, this structure allows header 32 to be removed to provide access to zipper 12 and the contents of the reclosable container while further providing evidence of prior opening, or tamper evidence.

[0015] FIG. 2 is a plan view of a typical reclosable container or bag 100 formed with perforated cap structure 10. Reclosable container or bag 100 includes front and rear panels 102, 104 (shown overlapping) of film with a bottom seal 106, side seals 108, 110. It is envisioned that one or more of seals 106, 108, 110 could be replaced by folds depending upon the particular method of formation of reclosable container or bag 100. However, it is specifically envisioned that reclosable container or bag 100 is formed by placing zipper tape 18 in a transverse direction along a film in a form fill and seal operation.

[0016] Main seal 112 is formed between front panel 102 and a first side of zipper tape 18 and is likewise formed between rear panel 104 and a second side of zipper tape 18. The zipper tape 18 can be made from a material that will keep the inner portions of the first and second sides of zipper tape 18 from sealing together during the formation of the main seal 112 but still allow the zipper segment end seals proximate to side seals 108, 110 to seal together. This may be done by providing a non-seal layer on the zipper segment but applying sufficient additional heat and pressure, such as with a hot knife or an ultrasonic welder, to form the zipper segment end seals. Alternately, the thickness of zipper tape 18 or cap 24 can be chosen to provide enough insulation from main seal 112 to prevent the inner portions of the first and second sides of zipper tape 18 from sealing to each other while similarly providing sufficient additional heat and pressure to form the zipper segment end seals.

[0017] An additional envisioned embodiment of bag 100 would include a seal or fold along top 111 and further include lines of perforation along front and rear panels 102, 104 downwardly adjacent from top 111.

[0018] Additionally, as shown in FIGS. 2 and 3, the lateral ends of zipper tape 18 have wide flat crush areas 116, 118 formed inwardly adjacent from side seals 108, 110, respectively. In crush areas 116, 118, the interior of first and second sides of zipper tape 18 are sealed together. Notches 120, 122 are formed in the sides of crush areas 116, 118 aligned with the ends of first and second lines of perforation 28, 30 (first and second lines of perforation 28, 30 shown overlapping each other). Additionally, the bag film of front and rear panels 102, 104 is removed to form a semi-circular notch 126 inwardly adjacent from side seal 108 and downwardly adjacent from top 111 of bag 100. This removal is typically done to the front and rear panels 102, 104 prior to the attachment of zipper tape 18 in order to avoid damage to the zipper tape 18. The lower portion of semi-circular notch 126 is generally aligned with notch 120 and first and second lines of perforation 28, 30 in order to allow the user to grasp the portion of crush area 116 above notch 126 (that is, header 32 of loop 28 as shown in FIG. 1) and to easily tear along first and second lines of perforation 28, 30 above main seal 112 in order to provide access to zipper 12. Upon opening zipper 12, the user has access to the contents of reclosable package or bag 100. This embodiment further requires zipper 12 to be segmented from the remaining supply of zipper by cutting in the middle of a large crush area to form the zipper segment and create the two separate crush areas 116, 118.

[0019] FIG. 4 shows a second embodiment of the end seals of zipper tape 18. In this embodiment, crush areas 116, 118 are somewhat narrower than that of the embodiment of FIGS. 2 and 3. Additionally, crush areas 116, 118 are inwardly inset from the ends of zipper tape 18. This embodiment similarly requires zipper 12 to be segmented between the crush areas 116, 118.

[0020] FIG. 5 shows a third embodiment of the end seals of zipper tape 18. In this embodiment, the crush areas 116, 118 of FIGS. 2, 3 and 4 are replaced with seal ends 130, 132 which are segment sealed at the very edges.

[0021] Thus the several aforementioned objects and advantages are most effectively attained. Although preferred embodiments 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.

Claims

1. A reclosable container including:

a first film panel and a second film panel with at least some edges thereof joined together;

a zipper tape with first and second interlocking profile members, said first and second interlocking profile members being separated by a portion of width of said zipper tape, said portion of width of said zipper tape being shaped into a loop thereby allowing said first and second interlocking profile members to engage with each other;

said zipper tape including at least one line of weakness spaced between and parallel to said first and second interlocking profile members;

said zipper tape including an additional layer covering one side of said at least one line of weakness thereby providing a seal to prevent passage of matter through said at least one line of weakness prior to tearing of said at least one line of weakness;

said zipper tape being sealed to an interior of said first and second film panels inwardly adjacent from one edge where said first and second film panels are joined together, whereby tearing said at least one line of weakness provides access to said first and second interlocking profile members, and subsequently provides evidence of access to said first and second interlocking profile members.

2. The reclosable container of claim 1 wherein said zipper tape includes a first end, a second end, a first lateral edge and a second lateral edge, wherein said first interlocking profile is inwardly adjacent from and parallel to said first lateral edge, said second interlocking member is inwardly adjacent from and parallel to said second lateral edge.

3. The reclosable container of claim 2 wherein said first end includes a first crush area wherein a portion of said first side is sealed to a portion of said second side and wherein said second end includes a second crush area wherein a portion of said first side is sealed to a portion of said second side.

4. The reclosable container of claim 2 wherein said first and second crush areas extend to said first end and said second end, respectively.

5. The reclosable container of claim 2 wherein said first and second crush areas are spaced inwardly from said first and second ends, respectively.

6. The reclosable container of claim 2 wherein said first end is sealed wherein a portion of said first side is sealed to a portion of said second side and wherein said second end is sealed wherein a portion of said first side is sealed to a portion of said second side.

7. The reclosable container of claim 3 wherein said first and second crush areas include notches aligned with said at least one line of weakness.

8. The reclosable container of claim 7 wherein said at least one line of weakness includes two parallel lines of weakness and wherein said portion of width of said zipper tape shaped into a loop aligns said two parallel lines of weakness with each other.

9. The reclosable container of claim 8 wherein said two parallel lines of weakness are two parallel lines of perforation.

10. The reclosable container of claim 9 wherein said loop includes an additional layer of material inwardly from said zipper tape.

11. The reclosable container of claim 10 wherein said zipper tape includes a cylindrical stiffener located inwardly from an apex of said loop.

12. A zipper tape for application in the transverse direction on a web of material, the zipper tape including a web of material with first and second parallel interlocking profile members spaced from each other, at least one line of weakness in said web positioned between said first and second parallel interlocking profile members, and an additional layer covering one side of said at least one line of weakness thereby providing a seal to prevent passage of matter through said at least one line of weakness prior to tearing of said at least one line of weakness.

13. The zipper tape of claim 12 further including a first end, a second end, a first side and a second side, wherein said first interlocking profile is inwardly adjacent from and parallel to said first side, said second interlocking member is inwardly adjacent from and parallel to said second side.

14. The zipper tape of claim 13 wherein said first end includes a first crush area wherein a portion of said first side is sealed to a portion of said second side and wherein said second end includes a second crush area wherein a portion of said first side is sealed to a portion of said second side.

15. The zipper tape of claim 13 wherein said first and second crush areas extend to said first end and said second end, respectively.

16. The zipper tape of claim 13 wherein said first and second crush areas are spaced inwardly from said first and second ends, respectively.

17. The zipper tape of claim 12 wherein said first end is sealed wherein a portion of said first side is sealed to a portion of said second side and wherein said second end is sealed wherein a portion of said first side is sealed to a portion of said second side.

18. The zipper tape of claim 14 wherein said first and second crush areas include notches aligned with said at least one line of weakness.

19. The zipper tape of claim 18 wherein said at least one line of weakness includes two parallel lines of weakness and wherein said zipper tape is looped thereby aligning said two parallel lines of weakness with each other.

20. The reclosable container of claim 19 wherein said two parallel lines of weakness are two parallel lines of perforation.