US20110081103A1

US20110081103A1 - Drawstring Trash Bag

Info

Publication number: US20110081103A1
Application number: US12/573,178
Authority: US
Inventors: George M. Hall
Original assignee: Poly-America LP
Current assignee: Poly-America LP
Priority date: 2009-10-05
Filing date: 2009-10-05
Publication date: 2011-04-07
Also published as: CA2686646A1

Abstract

The present invention is directed toward a drawstring trash bag. The drawstring trash bag features an upper opening with a first and second hem extending along the upper opening of the bag. A first drawstring is disposed within the first hem while a second drawstring is disposed within the second hem of the bag. The first drawstring and the second drawstring have different elastic properties. Both drawstrings may be pulled through cut-outs that are centrally located on the respective first and second panels along the upper opening. The elastic drawstring preferably has an elastic recovery percentage that is at least 10 points greater than the elastic recovery percentage of the non-elastic drawstring.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS

Not applicable.

BACKGROUND AND SUMMARY OF THE INVENTION

1. Field of the Invention
The present invention relates to improvements in the construction and manufacture of polymeric bags. In particular, the present invention relates to improvements in the construction and manufacture of drawstring-type polymeric bags, especially polymeric trash bags.
2. Description of the Related Art and the Present Invention
Polymeric bags are ubiquitous in modern society, available in a variety of different combinations of materials, capacities, thicknesses, dimensions and colors. Such bags are used for a variety of purposes including for long-term storage, food storage and trash collection. In response to consumer demand, manufacturers of polymeric bags have developed innovations over the years to improve the utility and performance of polymeric bags. The present invention is of particular interest to polymeric bags used for trash collection and to the method for securely closing and carrying such bags. Furthermore, the present invention provides advantages when applying such bags to trash receptacles.
The utility and desirability of polymeric trash bags is in part driven by the convenience of securely closing and carrying a particular trash bag after filling it with debris. Over the years, several different methods have been available, each method having certain advantages and disadvantages. One of the oldest methods for securing a trash bag is to provide a twist-tie to accompany the bag, allowing a consumer to bunch the upper opening of the bag together after filling. The twist-tie may be used to hold the bunched plastic together, securing the bag for disposal. Another common configuration is the flapped bag where the top edges of the bag are cut in a wave-like pattern to provide two or more flaps extending upward from the top of the bag. These flaps allow the user to tie the opposing flaps together, securing the contents of the bag inside while also providing a convenient handle for carrying the filled bag.
Drawstring bags are one of the most popular solutions to the problems associated with securing and carrying the bags. As the name suggests, drawstring bags feature drawstrings, also known as draw tapes, incorporated into the bag design. In a typical embodiment of a drawstring bag, drawstrings are enclosed within hems running along the top edges of the panels which make up the trash bag. Seals are then provided near the respective upper corners of the bag. The seals weld the drawstrings and the panels of the bag together and are formed by applying heat and pressure. The seals serve to anchor the ends of the drawstrings to the upper corners of the bag and within the hems. The drawstrings may then be pulled through the centrally-located cut-out of each hem to pull the upper corners of the bag together. This facilitates closure of the upper opening and secures the trash within the bag. After securely closing the bag, the drawstrings also provide a convenient handle for carrying the filled bag.
Prior art drawstring trash bags are known to utilize elastic drawstrings. Elastic drawstring bags are desirable because they allow a user to stretch the top of the bag, which contains the elastic drawstring, over a trash receptacle. When the elastic drawstring is released, it contracts and grips the outside of the trash receptacle, holding the bag in place. In the prior art elastic drawstring bags, an elastic drawstring is located in each of the two hems at the top of the bag as with a traditional drawstring trash bag. However, the drawstrings are only accessible from the sides of the bag rather than through centrally-located cut-outs in the middle of the panel hems. The configuration of this prior art elastic drawstring bag is both unusual and awkward. More importantly, the prior art elastic drawstring bag configuration is also known to suffer from certain additional disadvantages.
In addition to being awkward to use, another disadvantage of the prior art elastic drawstrings is evident in the way the drawstrings are used to close the bag. The prior art configuration makes it more difficult to close the top of the bag because, unlike the conventional drawstring trash bag, the elastic drawstrings of the prior art elastic drawstring bags are not anchored to the body of the bag. Pulling the elastic drawstrings does not close the bag by itself. In fact, to close the bag with a meaningful degree of effectiveness, both ends of the elastic drawstrings must be pulled upward in tandem. Furthermore, even after pulling the drawstrings and closing the bag, the configuration of the prior elastic drawstring bags also prevents the bag from substantially closing due to the large notches cut out of the bag.
Another disadvantage of the prior art elastic drawstring trash bags is that the elastic drawstrings do not function as effectively as a carrying handle when compared to non-elastic drawstrings. By their very nature, elastic drawstrings are designed to stretch when a force is applied to the respective ends of the elastic drawstrings. Therefore, after tying the elastic drawstrings together to secure the bag, carrying the bag by the tied elastic drawstrings can have a tendency to stretch the elastic drawstrings. Moreover, as the weight of the trash in the bag increases, the stretching of the elastic drawstring will also have a tendency to increase when the bag is carried.
To overcome these disadvantages, the prior art elastic drawstring trash bags focus on using thicker drawstrings. One problem with using materials which exhibit useful elastic and recovery properties for this application is that the tensile strength at yield of the drawstring is significantly reduced compared to a traditional drawstring of the same thickness. Therefore, elastic drawstrings of the prior art are typically thicker than non-elastic drawstrings to provide comparable tensile strength at yield. A suitable tensile strength at yield is necessary to prevent the drawstring from ripping or stretching excessively as the bag is carried by the elastic drawstrings. Generally speaking, the elastic drawstrings of the prior art are approximately 3 times thicker than a standard non-elastic drawstring. Accordingly, the thicker elastic drawstring requires more material and significantly increases the cost of the prior art elastic drawstring over a non-elastic drawstring.
In view of the foregoing, it would be desirable to offer improved versions of drawstring bags over what is known in the prior art. It would specifically be desirable to offer a drawstring trash bag with the advantage offered by the prior art elastic drawstring bag to allow securing a bag onto a receptacle while also providing the carrying and closing benefits of traditional non-elastic drawstring bags. The present invention addresses these needs.

SUMMARY OF THE INVENTION

The present invention is directed toward an improved construction of a drawstring trash bag. The bag is comprised of a first panel and a second panel, with a first hem in the first panel. The first hem extends along an upper opening of the bag with a first drawstring disposed within the first hem. A second hem is provided in the second panel. The second hem extends along the upper opening of the bag and a second drawstring is disposed within the second hem. The first and second drawstrings have different elastic properties. In particular, the first drawstring is an elastic drawstring and the second drawstring is a non-elastic drawstring.
In some embodiments of the present invention, a sealing area is located in each of the respective upper corners of the bags. Each sealing area comprises one or more seals to weld the first panel, the second panel, the elastic drawstring, and the non-elastic drawstring together.
It is contemplated that the present invention may be utilized in ways that are not fully described or set forth herein. The present invention is intended to encompass these additional uses to the extent such uses are not contradicted by the appended claims. Therefore, the present invention should be given the broadest reasonable interpretation in view of the present disclosure, the accompanying FIGURE, and the appended claims.

BRIEF DESCRIPTION OF THE RELATED DRAWINGS

A full and complete understanding of the present invention may be obtained by reference to the detailed description of the present invention and preferred embodiment when viewed with reference to the accompanying drawing.

FIG. 1 provides a perspective view of a drawstring trash bag as contemplated by one embodiment of the present invention.

DETAILED DESCRIPTION OF THE INVENTION

The present disclosure illustrates one or more preferred embodiments of the present invention. It is not intended to illustrate or encompass all embodiments contemplated by the present invention. In view of the disclosure of the present invention contained herein, a person having ordinary skill in the art will recognize that innumerable modifications and insubstantial changes may be incorporated or otherwise included within the present invention without diverging from the spirit of the invention. Therefore, it is understood that the present invention is not limited to those embodiments disclosed herein. The appended claims are intended to more fully and accurately encompass the invention to the fullest extent possible, but it is also fully appreciated that certain limitations on the use of particular terms is not intended to conclusively limit the scope of protection.
FIG. 1 provides a perspective view of one embodiment of the drawstring trash bag 100 disclosed herein. In the depicted embodiment, the drawstring trash bag 100 is a polyethylene bag constructed from a first panel 102 and a second panel 104. The drawstring trash bag 100 has two side edges 106 and a bottom 108. The top of the respective first panel 102 and second panel 104 define the upper opening 112 of the drawstring trash bag 100 into which trash and refuse may be disposed.
Typically, the first panel 102 and second panel 104 are formed from a single polyethylene sheet folded in half. The fold of the polyethylene sheet typically forms the bottom 108 of the drawstring trash bag 100. After the polyethylene sheet is folded, side seals 110 are provided which extend substantially the entire length of the drawstring trash bag 100 and weld the first panel 102 and second panel 104 together. The side seals 110 are generally located slightly interior from the side edges 106 of the panels 102 and 104. The distance between these two side seals 110 defines the usable width of the drawstring trash bag 100. A person of ordinary skill in the art would recognize that the present invention is not necessarily limited to this method of construction and that alternative bag construction techniques may be used without diverging from the spirit of the present invention.
In the depicted embodiment of FIG. 1, the first panel 102 has a first hem 130 which extends substantially the entire width of the drawstring trash bag 100 and along the upper opening 112. Similarly, the second panel 104 has a second hem 132 which extends substantially the entire width of the drawstring trash bag 100 along the upper opening 112. An elastic drawstring 140 is disposed within the first hem 130 while a non-elastic drawstring 142 is disposed within the second hem 132. Both the elastic drawstring 140 and the non-elastic drawstring 142 extend substantially the entire width of the drawstring trash bag 100.
All polymeric materials exhibit some degree of elastic properties. The difference in elastic properties between the elastic drawstring 140 and the non-elastic drawstring 142 can be quantified by their respective elastic properties. As a point of reference, ASTM D5459 Standard Test Method for Machine Direction Elastic Recovery and Permanent Deformation and Stress Retention of Stretch Wrap Film available from ASTM International, which is incorporated herein by reference, sets forth a method for determining certain elastic properties of films. The elastic properties of particular interest here include, but are not limited to, elastic recovery, permanent deformation, and stress retention. The present invention contemplates that the tests to determine the elastic properties of the elastic drawstring 140 and non-elastic drawstring 142 would be done using an initial elongation of 25%, but other initial elongations could be utilized if the particular application warranted such tests.
The present invention contemplates that the elastic properties of the elastic drawstring 140 and the non-elastic drawstring 142 will be different. In particular embodiments, it is expected that the elastic drawstring 140 will have an elastic recovery percentage that is greater than the elastic recovery percentage of the non-elastic drawstring 142. Furthermore, in some embodiments of the present invention, the elastic recovery of the elastic drawstring 140, when stated as a percentage, should be at least 10 percentage points greater than the elastic recovery for the non-elastic drawstring 142. In certain embodiments of the present invention, the elastic drawstring 140 would exhibit an elastic recovery percentage of at least 70% while the non-elastic drawstring 142 would exhibit an elastic recovery percentage of less than 55%.
In other embodiments of the present invention, the differences between the elastic properties of the elastic drawstring 140 and the non-elastic drawstring 142 may be stated in terms of permanent deformation. As an example, in certain embodiments of the present invention, the permanent deformation of the elastic drawstring 140 will be less than the permanent deformation of the non-elastic drawstring 142. In particular, in some embodiments, it is expected that the permanent deformation of the elastic drawstring 140, when stated as a percentage, should be at least 10 percentage points greater than the permanent deformation for the non-elastic drawstring 142. In certain embodiments of the present invention, the elastic drawstring 140 would exhibit a permanent deformation that is less than 30% while the non-elastic drawstring 142 would exhibit a permanent deformation of greater than 45%.
At each upper corner of the drawstring trash bag, a sealing area 120 is provided to weld the first panel 102, the second panel 104, the elastic drawstring 140, and the non-elastic drawstring 142 together. Each sealing area 120 is comprised of one or more individual seals which in turn define an inner seal boundary 124. The bag opening width is therefore defined by the distance between the respective inner seal boundaries 124. In certain embodiments of the present invention, the bag opening width is less than the usable bag width.
Using an elastic drawstring 140 and a non-elastic drawstring 142 in combination with one another overcomes disadvantages of prior art drawstring trash bags. Unlike traditional drawstring trash bags, the incorporation of the elastic drawstring 140 allows the bag to grip the can when the bag is pulled over a trash receptacle. And, unlike prior art elastic drawstring trash bags, the bag of the present invention 100 can be manufactured more cost effectively without the use of two elastic drawstrings, provides a more traditional configuration with central-access cut outs, and effectively ensures a good closure.
As noted, the embodiments depicted herein are not intended to limit the scope of the present invention. Indeed, it is contemplated that any number of different embodiments may be utilized without diverging from the spirit of the invention. Therefore, the appended claims are intended to more fully encompass the scope of the present invention.

Claims

1. An drawstring trash bag comprising:

a bag comprised of a first panel and a second panel,

a first hem in the first panel, the first hem extending along an upper opening of the bag,

a first drawstring disposed within the first hem,

a second hem in the second panel, the second hem extending along the upper opening of the bag,

a second drawstring disposed within the second hem,

the first drawstring and the second drawstring having different elastic properties.

2. The drawstring trash bag of claim 1, further comprising

the first drawstring being an elastic drawstring, the second drawstring being a non-elastic drawstring.

3. The drawstring trash bag of claim 1, further comprising

an elastic recovery percentage of the first drawstring being greater than an elastic recovery percentage of the second drawstring.

4. The drawstring trash bag of claim 3, further comprising

the elastic recovery percentage of the first drawstring being at least 10 points greater than the elastic recovery percentage of the second drawstring.

5. The drawstring trash bag of claim 3, further comprising

the elastic recovery percentage of the first drawstring being greater than 70%, and

the elastic recovery percentage of the second drawstring being less than 55%.

6. The drawstring trash bag of claim 1, further comprising

a permanent deformation percentage of the first drawstring being less than a permanent deformation percentage of the second drawstring.

7. The drawstring trash bag of claim 6, further comprising

the permanent deformation percentage of the first drawstring being at least 10 points less than the permanent deformation percentage of the second drawstring.

8. The drawstring trash bag of claim 6, further comprising

the permanent deformation percentage of the first drawstring being less than 30%, and

the permanent deformation percentage of the second drawstring being greater than 45%.

9. The drawstring trash bag of claim 1, further comprising

a first centrally-located cut-out in the first hem, and a second centrally-located cut-out in the second hem.

10. The drawstring trash bag of claim 1, further comprising:

a first sealing area located in a first upper corner of the bag, the first sealing area welding the first panel, the second panel, the first drawstring, and the second drawstring together, and

a second sealing area located in a second upper corner of the bag, the second sealing area welding the first panel, the second panel, the first drawstring, and the second drawstring together.

11. The drawstring trash bag of claim 10, further comprising

12. The drawstring trash bag of claim 10, further comprising:

the first sealing area comprising one or more seals, and

the second sealing area comprising one or more seals.

13. The drawstring trash bag of claim 10, further comprising:

a distance between a first side seal of the drawstring trash bag and a second side seal of the drawstring trash bag defining a usable bag width,

a distance between an inner boundary of the first sealing area and an inner boundary of the second sealing area defining an upper opening width, and

the upper opening width being less than the usable bag width.

14. The drawstring trash bag of claim 13, further comprising