US20030215165A1

US20030215165A1 - Easy-open strip and bags incorporating the same

Info

Publication number: US20030215165A1
Application number: US10/151,388
Authority: US
Inventors: Robert Hogan; Eric Plourde
Original assignee: Illinois Tool Works Inc
Current assignee: Illinois Tool Works Inc
Priority date: 2002-05-20
Filing date: 2002-05-20
Publication date: 2003-11-20
Also published as: US7395642B2; EP1364884A1; US20050008268A1

Abstract

An easy-open closure arrangement for bags is described. The closure arrangement includes a base web having a pair of longitudinal edges with a pair of perforated tear lines running in the same direction as the longitudinal edges. The perforated tear lines are located substantially equidistant from the longitudinal edges. A frangible layer is attached to one side of the base web with the frangible layer being positioned over the perforated tear lines to obstruct the perforations on one side. A tear bead is attached to the frangible layer on the side of the frangible layer opposite from the base web at a position between the location of the perforated tear lines. Alternative closure arrangements and bags incorporating the closure arrangements are also described.

Description

FIELD OF THE INVENTION

The present invention relates to a easily-openable closure arrangement for bags, and more particularly to perforated strips useful as closure arrangements for bags.

BACKGROUND OF THE INVENTION

Bulk consumer items (e.g., potting soil, seed, and animal feed as well as food products for service applications) are often packaged in large bags (e.g., pouches or satchels) for sale to the public. The weight of these bulk items often necessitates that the material for the bag be durable and tear-resistant. Typically, bulk item bags are made of a tear-resistant plastic, a tear-resistant paper-based material, or some combination of the two. However, the opening of bulk item bags is often difficult without the use of cutting instruments due to the tear resistance of the bag material. Thus, there is a need in the art for bulk item bags that can easily be opened without the use of cutting instruments.

It is, therefore, an object of the present invention to provide easy-open closure arrangements for bulk item bag which facilitate access to the interior of the bag without resort to cutting instruments. It is also an object of the present invention to provide bulk item bags incorporating the easy-open closure arrangements of the present invention.

SUMMARY OF THE INVENTION

The present invention provides an easy-open closure arrangement for a bag which includes a base web, a frangible layer, and a tear bead. The base web has a pair of longitudinal edges with a pair of perforated tear lines running generally parallel to the longitudinal edges and substantially equidistant from the longitudinal edges. The frangible layer is attached to one side of the base web and is positioned over the perforated tear lines to obstruct the perforations on one side. The tear bead is attached to the frangible layer on the side opposite from the base web and is positioned generally centrally between the location of the perforated tear lines. Preferably, the base web is formed from a material such as a thermoplastic polymer, a paper-based material, other multilayer webs used in the packaging industry or a combination thereof. The frangible layer thus serves to seal the perforated lines keeping out small particles and insects and preventing small particles within the packages from leaking out. The frangible layer also aids in keeping moisture in or out.

The present invention also provides an easy-open bag incorporating the above-described closure arrangement. The bag includes opposing side walls that form the bottom and sides of the bag. The above-described closure arrangement may be attached to the opposing side walls to form the top of the bag or the closure may be provided over a slit in one of the walls. The closure can be attached to the inside or outside of the bag wall.

Advantageously, the closure arrangements and bags of the present invention provide a unique solution for providing access to the contents of bulk item bags without resorting to cutting instruments. These and other advantages will become more readily apparent from the detailed description set forth below.

BRIEF DESCRIPTION OF THE DRAWINGS

In the accompanying drawings: [0007]
FIG. 1 is a perspective view, with portions broken away, of an easy-open closure arrangement in accordance with the present invention in an unfolded state constructed; [0008]
FIG. 2 is a perspective view of the easy-open closure arrangement of FIG. 1 in a folded and partially-opened state; [0009]
FIG. 3 is a cross-sectional view of a bulk item bag incorporating the easy-open closure arrangement of FIG. 1 in a folded state; [0010]
FIG. 4 is a plan view of a bulk item bag with the easy-open closure arrangement of FIG. 1 attached to one of the opposing side walls; [0011]
FIG. 5 is a cross-sectional view, taken as indicated by line [0012] 5-5, of the bag shown in FIG. 4;
FIG. 6 is a plan view of a bulk item bag incorporating an alternative embodiment of the easy-open closure arrangement of the present invention; and [0013]
FIG. 7 is a cross-sectional view, taken as indicted by line [0014] 7-7, of the bag shown in FIG. 6.

DETAILED DESCRIPTION OF THE INVENTION

FIG. 1 is a perspective view of one embodiment of the easy-open closure arrangement of the present invention. The [0015] closure arrangement 10 includes a base web 12, which is formed from a length of a thermoplastic polymer such as polyethylene, a length of paper-based material or a combination of the two materials (e.g., a laminate). Preferably, the thermoplastic polymer and paper-based material are not readily frangible. Base web 12 has a pair of longitudinal edges and a pair of perforated tear lines 14, 16 running generally parallel to the longitudinal edges. Perforated tear lines 14, 16 are located substantially equidistant from the longitudinal edges and the perforations are spaced sufficiently close so that the tear lines will rupture upon the application of a tearing force to the tear lines.
Attached to one side of [0016] base web 12 is a layer of a frangible thermoplastic film 18 (hereinafter “frangible layer 18”). Frangible layer 18 is positioned on one side of the base web 12 so as to obstruct (or seal) the perforations of perforated tear lines 14, 16. In the context of the present invention “frangible” means that the material is easily broken or ruptured. An example of a thermoplastic polymer to be used for frangible layer 18 is ethylene vinyl acetate (EVA). Frangible layer 18 is attached to the base web 12 by any of many techniques known in the art such as heat sealing, adhesive bonding, etc. As will be apparent to the skilled artisan, the method of choice for attaching the two layers will be partially dependent on the choice of material for base web 12. For example, if base web 12 is a thermoplastic polymer, frangible layer 18 can be adhered via heating sealing or via the use of a tie layer. Likewise, if base web 12 is a paper-based material, frangible layer 18 can be adhered thereto with an adhesive.
[0017] Frangible layer 18 has attached thereto a tear bead 22 on the side opposite from the base web 12. In accordance with the present invention, tear bead 22 is made of a generally tear resistant material (i.e., non-frangible) such as a cloth string, or plastic extrusion. In a preferred embodiment, the tear resistance of the tear bead 22 is greater than that of either the base web material 12 or the wall material of a bag incorporating the easy-open closure arrangements of the invention. Preferably, tear bead 22 is formed from a tear resistant thermoplastic polymer such as polypropylene or high-density polyethylene (HDPE) and may be attached by heat sealing, adhesive bonding or any other appropriate technique known in the art. The tear bead 22 is centrally located on frangible layer 18 between the position of perforated tear lines 14, 16 to substantially equalize the tearing force applied to tear lines 14, 16 as tear bead 22 is pulled away from the bag.
FIG. 2 is a perspective view of the easy-[0018] open closure arrangement 10 in a folded and partially open (i.e., torn) state. Closure arrangement 10 is folded at a location between and along the same direction as perforated tear lines 14, 16 so as to position frangible layer 18 and tear bead 22 within the interior of folded, closure arrangement 10 so that tear lines 14, 16 are obstructed on the interior side of closure arrangement 10. As shown in FIG. 2, the top of closure arrangement 10 is removed by tearing along perforated tear lines 14, 16 (16 not shown) by pulling along tear bead 22.
FIG. 3 is a cross-sectional view of [0019] bulk item bag 20 incorporating the folded easy-open closure arrangement 10 in accordance with invention. As shown in FIG. 3, opposing side walls 32, 34 are attached to closure arrangement 10 via base web 12. Opposing side walls 32, 34 are formed from a single length of bag forming material as shown in FIG. 3 or may be formed from two lengths of bag-forming material sealed at the end opposite from tear bead 22. Opposing side walls 32, 34 are attached to base web 12 by any of many well known techniques, such as heat sealing, adhesives, etc., dependent on the type of materials used for base web 12 and opposing side walls 32, 34. In a preferred embodiment, as shown in FIG. 3, opposing side walls 32, 34 are attached to base web 12 on the exterior side of closure arrangement 10 (i.e., the side of base web 12 opposite from frangible layer 18 and tear bead 22). Likewise, as shown in FIG. 3, closure arrangement 10 is folded in a position between and in the same direction as perforated tear lines 14, 16 so that frangible layer 18 and tear bead 22 face bag interior 36. To facilitate opening of closure arrangement 10, the point of attachment of opposing side wall 32, 34 to base web 12 is below perforated tear lines 14, 16 to avoid obstructing or covering the perforations of the tear lines.
FIG. 4 is a plan view of a sealed [0020] bulk item bag 30 incorporating easy-open closure arrangement 10 in an unfolded state. The bulk item bag 30 has opposing side walls 32, 34, a bottom 26 and a top 28. Side wall 32 is provided with a clearance opening 38 that provides access to bag interior. Closure arrangement 10 is positioned over clearance opening 38 so that the opening is completely located between perforated tear lines 14, 16 with frangible layer 18 and tear bead 22 facing the bag interior 36 and opposing side wall 32. An extension of tear bead 22, at one end of the bead extends past base web 12 and frangible layer 18 to provide a tab for opening closure arrangement 10 along perforated tear lines 14, 16.
FIG. 5 is a cross-sectional view of [0021] bulk item bag 30 along line 5-5 shown in FIG. 4. Tear bead 22 is centrally located within clearance 38 so as to provide a substantially equal tearing force to perforated tear lines 14, 16 as tear bead 22 is pulled away from opposing side wall 34. FIG. 5 also shows that base web 12 and frangible layer 18 are attached to opposing side wall 32 along both sides of clearance 38.
FIG. 6 is a plan view of a [0022] bulk item bag 50 incorporating easy-open closure arrangement 40, which is an alternative embodiment of the closure arrangement of the present invention. In this embodiment, base web 12 is omitted and one of the opposing side walls of the bag completes closure arrangement 40. Bulk item bag 50 has opposing side walls 32, 34 a bottom 26 and a top 28. Side wall 32 has pair of perforated tear lines 14, 16 running substantially parallel to one another. Frangible layer 18 is attached to the interior side of the opposing side wall 32 running in the same direction as perforated tear lines 14, 16. Frangible layer 18 is positioned over the perforation lines so that the perforations of both tear lines 14, 16 are sealed. Tear bead 22 is attached to frangible layer 18 on the interior side of wall 32 centrally located between the lines of perforation. An extension of tear bead 22 extends beyond frangible layer 18 and opposing side wall 32 to provide a tab for opening closure arrangement 40. Bag 50 is opened by pulling tear bead 22 away from opposing side wall 34 thereby tearing opposing side wall 32 along perforated tear lines 14, 16.
While the invention has been described as to what are presently believed to be the preferred embodiments of the invention, those skilled in the art will recognize that various changes and modifications can be made to the invention without departing from the spirit of the invention. All such changes and modification will fall within the scope of the present invention and are therefore intended to be claimed. [0023]

Claims

Having thus described the invention, what is claimed is:

1. An easy-open closure arrangement for a package comprising:

a base web having a pair of longitudinal edges, a pair of spaced perforated tear lines extending between said longitudinal edges;

a frangible layer attached to one side of said base web overlying said perforated tear lines' perforations.

2. The easy-open closure arrangement in accordance with claim 1 further comprising a tear bead positioned between said tear lines attached to said frangible layer on a side of said frangible layer opposite from said base web.

3. The easy-open closure arrangement in accordance with claim 1, wherein said base web is formed from a material selected from the group consisting of a thermoplastic polymer, a paper-based material, or a combination thereof.

4. The easy-open closure arrangement in accordance with claim 2 wherein said perforated tear lines and said tear bead are parallel.

5. The easy-open closure arrangement of claim 3, wherein said tear bead is positioned centrally between said perforated tear lines.

6. An easy-open bag comprising:

a pair of opposing side walls; and

a closure arrangement attached to at least one of said opposing side walls, said closure arrangement including:

a base web having a pair of longitudinal edges, a pair of spaced perforated tear lines extending between said longitudinal edges; and

7. The easy-open bag in accordance with claim 6 wherein said closure arrangement base web is attached to top ends of both of said opposing side walls thereby forming a top for said bag.

8. The easy open bag in accordance with said claim 7 wherein said base web is folded at a position between said perforated tear lines.

9. The easy open bag in accordance with claim 8 wherein said frangible layer is attached to the interior side of said base web and further comprising a tear bead attached to said frangible layer on the side of said frangible layer opposite from said base web, wherein said tear bead is positioned between the perforated tear lines.

10. The easy open bag in accordance with claim 6 further comprising a clearance opening in one of said side walls and said closure is positioned over said opening.

11. The easy open bag in accordance with claim 10 wherein said clearance opening is centrally positioned between said perforated tear lines.

12. The easy open bag in accordance with claim 10 further comprising a tear bead adhered to said frangible layer on a side of said frangible layer facing the other of said side walls, wherein said tear bead is positioned between the location of said perforated tear lines and at one end protrudes through said bag thereby providing a tab for opening said bag.

13. An easy-open bag comprising:

a pair of opposing side walls, wherein one of said walls has a pair of spaced perforated tear lines; and

a frangible layer attached to said wall having spaced perforated tear lines, said frangible layer overlying said perforated tear lines' perforations.

14. The easy open bag in accordance with claim 13 wherein said frangible layer is attached to the interior side of said wall having spaced perforated tear lines and further comprising a tear bead attached to said frangible layer on the side of said frangible layer opposite from said wall having spaced perforated tear lines, wherein said tear bead is positioned between the perforated tear lines.

15. The easy open bag in accordance with claim 14 wherein said tear bead at one end protrudes through said bag thereby providing a tab for opening said bag.