WO2012064688A2

WO2012064688A2 - Reclosable zipper with coextruded sealing elements

Info

Publication number: WO2012064688A2
Application number: PCT/US2011/059698
Authority: WO
Inventors: Victor Matias
Original assignee: Illinois Tool Works Inc.
Priority date: 2010-11-11
Filing date: 2011-11-08
Publication date: 2012-05-18
Also published as: WO2012064688A3

Abstract

Reclosable zippers for reclosable packages are disclosed. Foam elements, similar soft, flexible elements, or adhesive elements are coextruded onto the zipper profile in order to create a tight seal when the zipper of the reclosable package is closed. Alternatively, adhesive beads are coextruded onto the bag walls. The beads sandwich together when the bag is closed to form a tight seal but separate when the profile is opened.

Description

RECLOSABLE ZIPPER WITH

COEXTRUDED SEALING ELEMENTS

BACKGROUND OF THE DISCLOSURE

[0001] This application claims priority under 35 U.S.C. §119(e) of U.S. provisional application serial no. 61/412,634 filed November 11, 2010, the disclosure of which is hereby incorporated by reference in its entirety.

Field of the Disclosure

[0002] The present disclosure relates to zippers for reclosable packages wherein the zipper profiles include coextruded sealing elements, particularly including a coextruded soft material or adhesive material in order to achieve an improved sealing quality.

Description of the Prior Art

[0003] The art of zipper profiles for reclosable packages is well-developed and generally satisfactory for its intended purposes. However, these zipper profiles have varying degrees of leak resistance. Further improvements in leak resistance are constantly being sought, particularly if the improvements in leak resistance can be achieved without making the zipper more difficult to operate or increasing the production costs.

OBJECTS AND SUMMARY OF THE DISCLOSURE

[0004] It is therefore an object of the present disclosure to provide a zipper for a reclosable package wherein improved sealing quality and leak resistance are achieved.

[0005] It is therefore a further object of the present disclosure to provide a zipper which is not more difficult for consumers to operate than prior art zippers.

[0006] It is therefore a still further object of the present disclosure to provide a zipper which can be manufactured without any significant decrease in manufacturing speed or significant increase in manufacturing cost, with respect to prior art zippers.

[0007] A first embodiment of the disclosure includes a zipper profile which includes coextruded zipper closure profile elements which include either a softer material or an adhesive layer of material in order to improve the quality of the seal when the reclosable zipper or the reclosable bag is closed. In a first embodiment, soft material is coextruded into the notched areas near the male or female closure profile. In the second embodiment, the coextruded layer is a resealable adhesive. The adhesive or soft material elements could be placed within the notched areas separate from the closure profiles, or could be placed within the closure profiles. Alternatively, a thin layer of adhesive on the film could be used, thereby typically avoiding any visible sign of a profile. In the embodiment using adhesive, the clip or slider used to close the profiles presses the adhesive surfaces together to close, but the adhesive is close enough to the plow of the slider or clip so that the plow will separate the surfaces when opening. Additionally, the locking elements themselves could also be coextruded with a soft material that will wrap around the plow to improve leak resistance. Various sliders can be coextruded to improve leak resistance.

[0008] In a further embodiment, adhesive beads could be coextruded onto the bag walls across the width or expanse of the bag mouth. The beads would sandwich together when the bag is closed to form a tight seal but would separate when the profile is opened.

BRIEF DESCRIPTION OF THE DRAWINGS

[0009] Further objects and advantages of the disclosure will become apparent from the following description and from the accompanying drawing, wherein:

[0010] Figure 1 is a cross-sectional view of a first or second embodiment of a zipper profile of the disclosure, shown in an open configuration.

[0011] Figure 2 is a cross-sectional view of a first or second embodiment of a zipper profile of the disclosure, shown in a closed configuration.

[0012] Figure 3 is a cross-sectional view of a first or second embodiment of a zipper profile of the disclosure, illustrating the operation of a slider or clip.

[0013] Figure 4 is a perspective view of a typical reclosable package with a zipper of the present disclosure.

[0014] Figures 5a and 5b are cross-sectional views of a third embodiment of a zipper profile or closure of the present disclosure, in the closed and open configuration, respectively. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[00010] Referring now to the drawings in detail wherein like numerals indicate like elements throughout the several views, one can see that the first and second embodiments of the present disclosure can be illustrated by Figures 1-3. Figures 1-3 illustrate a zipper 10 with a first zipper profile 12 and a second zipper profile 14. First and second zipper profiles 12, 14 are typically made from a polymeric material such as polyethylene or polypropylene, but those skilled in the art may recognize other materials after review of the present disclosure. First zipper profile 12 includes a first base (or flange) 16 with a first interlocking element 18 extending perpendicularly therefrom. First interlocking element 18 includes first post 20 and first distal hook 22. Likewise, second zipper profile 14 includes a second base (or flange) 26 with a second interlocking element 28 extending therefrom. Second interlocking element 28 includes second post 30 and second distal hook 32. As shown in Figure 2, first and second distal hooks 22, 32 interlock with each other in the closed configuration of zipper 10. First guide 36 extends perpendicularly from an end of first base (or flange) 16, adjacent to first interlocking element 18 so as to hold second interlocking element 28 in the closed or interlocked position as shown in Figure 2. Additionally, second and third guides 40, 42 extend perpendicularly from second base (or flange) 26 in a parallel closely-spaced configuration so as to form female notch 44 therebetween. Fourth guide 46 extends perpendicularly from first base (or flange) 16 thereby forming a male or post element for reception by female notch 44, thereby serving to align first and second profiles 12, 14 properly in the closed or interlocked position as shown in Figure 2. The distal end of fourth guide 46 includes a head 48 of soft, flexible, sponge-like, foam, or foamed material (first embodiment of the present disclosure), including, but not limited to, flexible foam or ethylene-vinyl acetate. The head 48 would have a duremeter value which indicates a higher degree of softness than that of the male or post element. Alternatively, the head 48 may be composed of adhesive material (second embodiment of the present disclosure). In either the first or second embodiments, the material of head 48 is preferably coextruded with the first profile 12. In the closed or interlocked configuration shown in Figure 2, this head 48, whether of foam material, soft material, or adhesive, forms a seal within female notch 44 thereby improving the leak-resistant qualities of the zipper 10. Second and third guides 40, 42 are sufficiently closely spaced so as to engage the head 48 thereby forming the seal. [00011] Figure 3 illustrates a slider (or clip) 50 which operates to open or close the zipper 10 of Figures 1 and 2. As with known sliders or clips, the user manually moves the slider 50 in an opening direction to separate the zipper profiles 12, 14 thereby achieving the configuration of Figure 1 or moves the slider 50 in a closing direction (the opposite of the opening direction) thereby achieving the configuration of Figure 2. Slider 50 includes first and second sidewalls 52, 54 joined by a top wall 56. The first and second sidewalls 52, 54 engage against first and second profiles 12, 14, respectively. Plow 58 extends perpendicularly from top wall 56, into the interior of slider 50 so as to separate the first and second interlocking elements 18, 28.

[00012] An advantage of the resulting design is that the soft material or adhesive of head 46 will be more pliant or forgiving than many prior art designs, thereby requiring less strict manufacturing tolerances and thereby making the zipper 10 easier to manufacture. Additionally, the material of head 48 will fill the female notch 44 and will create an improved seal with respect to many prior art mechanical designs By coextruding the soft or adhesive material within overlapping elements, a tighter seal will be produced than many prior art designs which simply coextrude compressible seals beneath the closure profile.

[00013] A typical reclosable package 100 including the zipper 10 is illustrated in Figure 4. The package 100 includes first and second sidewalls 102, 104 of polymeric material, such as, but not limited to, polyethylene or polypropylene. The first and second sidewalls 102, 104 are joined to each other, typically by lower seal 106 and side seals 108, 110, but sidewalls 102, 104 may also be formed from a single folded sheet of web thereby replacing lower seal 106 with a fold. First and second sidewalls 102, 104 are not joined to each other at the top edge, thereby forming mouth 110. Mouth 110 has zipper 10 affixed thereto to provide for reclosability. Zipper 10 typically includes slider 50.

[00014] Figures 5a and 5b illustrate respective closed and open configurations of a third embodiment of the present disclosure wherein first sidewall 102 includes first and second coextruded adhesive beads 120, 122 which are formed in closely spaced parallel configuration while second sidewall 104 includes a third coextruded adhesive bead 124 configured to be pressed between the first and second coextruded adhesive beads 120, 122. While cross-sectional views are shown, the adhesive beads 120, 122, 124 are envisioned as typically being formed as extending across substantially the entire width or expanse of the mouth 110 of a reclosable package 100 so as to form a closure as an alternative configuration of zipper 10. As illustrated in Figure 5b, in the closed configuration, the third coextruded adhesive bead 124 sandwiches against (i.e., is positioned between and touching) first and second coextruded adhesive beads 120, 122 to form a tight seal. However, third coextruded adhesive bead 124 separates from first and second coextruded adhesive beads 120, 122 when the zipper 10 is opened, as illustrated in Figure 5a.

[00015] The embodiments of the present disclosure are used to provide reclosable zippers 10 for reclosable packages 100, as illustrated, for containing any product which may be contained in reclosable packages 100, such as, but not limited to, foodstuffs and similar products.

[00016] 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

CLAIMS What is Claimed is:

1. A zipper for a reclosable package, including:

a first zipper profile with a first interlocking element;

a second zipper profile with a second interlocking element, wherein the first and second interlocking elements interlock with each other in a closed configuration of the zipper; the first zipper profile including a male guiding element;

the second zipper profile including a female guiding element for reception of the male guiding element; and

the male guiding element including a post element and head element at a distal end of the post element, wherein material of the head element is coextruded with material of the post element and is substantially softer than the material of the post element.

2. The zipper of Claim 1 wherein the material of the head element comprises a material chosen from the group consisting of a foam material, a foamed material, a sponge material and ethylene-vinyl acetate.

3. The zipper of Claim 2 wherein the zipper is comprises a polymeric material.

4. The zipper of Claim 3 wherein the post element is formed of the polymeric material.

5. The zipper of Claim 1 wherein the first zipper profile includes a first base.

6. The zipper of Claim 5 wherein the second zipper profile includes a second base.

7. The zipper of Claim 6 wherein the female guiding element is formed by parallel closely-spaced elements which extend perpendicularly from the second base.

8. The zipper of Claim 7 wherein spacing of the closely-spaced elements is sufficiently close to form a seal with the head element.

9. The zipper of Claim 8 wherein the first and second interlocking elements have respective first and second distal ends with respective first and second hooks which interlock with each other.

10. A zipper for a reclosable package, including:

a first zipper profile with a first interlocking element;

the male guiding element including a post element and head element at a distal end of the post element, wherein material of the head element is coextruded with material of the post element and is an adhesive.

1 1. The zipper of Claim 12 wherein the zipper is comprises a polymeric material.

12. The zipper of Claim 11 wherein the post element is formed of the polymeric material.

13. The zipper of Claim 12 wherein the first zipper profile includes a first base.

14. The zipper of Claim 13 wherein the second zipper profile includes a second base.

15. The zipper of Claim 14 wherein the female guiding element is formed by parallel closely-spaced elements which extend perpendicularly from the second base.

16. The zipper of Claim 15 wherein spacing of the closely-spaced elements is sufficiently close to form a seal with the head element.

17. The zipper of Claim 16 wherein the first and second interlocking elements have respective first and second distal ends with respective first and second hooks which interlock with each other.

18. A closure for a reclosable package, including:

first and second adhesive beads on a first package wall; and

a third adhesive bead on a second package wall;

wherein, upon closing the reclosable package, the third adhesive bead is positioned between and contacting the first and second adhesive beads.

19. The closure of Claim 18 wherein the first and second adhesive beads are parallel with each other.

20. The closure of Claim 19 wherein the first and second adhesive beads are coextruded with each other.