Patent Application
20160304275
The present disclosure is generally related to woven fabrics and containers and more particularly is related to high strength ribbon-woven disposable fabric articles.
Disposable refuse bags have typically involved the use of 3-mil polyethylene films which are formed into bags and provided on rolls for use in the containment or collection of lightweight refuse, preferably refuse which does not have any sharp edges, points or other protuberances which could cause the bag to rip or tear. Moreover, such bags are limited in the weight of the contents to normally 20 to 25 pounds, which means that a large majority of the bag is unfilled and therefore unused.
When such bags are used on construction sites for containing items, for instance, bricks, drywall pieces, two-by-fours with or without nails protruding therefrom, slate, tree limbs, cable, masonry, shingles, insulation, pipe, wire, gravel, metal or glass shards, typically these bags fail by either stretching and rupture due to the weight of the contents within the bag when the bag is lifted, or due to the puncturing, slicing or piercing of the bag film which has very little shear resistance. In such cases the puncture or hole produced propagates rapidly to cause the contents of the bags to spill out through the rip or unintended opening of the bag.
Typically, in the past, rubberized barrels were utilized at construction sites to contain the refuse that existed at the site. However, these barrels are both expensive and are subject to theft. Moreover, the barrels themselves take up a considerable amount of space and are relatively heavy in and of themselves. The amount of rubber necessary to form such barrels causes such barrels to weigh, for instance, ten pounds when empty. Also, these barrels, due to their cost, are not throwaway items and must be stored when not in use. Though the barrels themselves may be nested to reduce the amount of storage space, when these barrels are nested they oftentimes stick to each other and are difficult to dislodge.
The result for jobsite cleanup is either to use the expensive, large barrels or to utilize polyethylene continuous film bags, both of which are unsatisfactory for the above reasons.
Ribbon-woven fabrics made from new polyethylene terephthalate (PET) have been described in U.S. Pat. No. 7,510,327, entitled “High Strength Ribbon-Woven Disposable Bag for Containing Refuse”. The use of new PET has allowed for the creation of high-strength bags and fabrics which may be used for containment and disposal of construction waste, however, new PET is relatively costly compared to recycled polyethylene terephthalate (RPET). To date, RPET has not been shown to able to be suitable for use in bags, fabrics or other containers which have must withstand the rigors of containing and disposing of construction waste because RPET has not been shown to have the strength necessary for such use due to contaminants commonly found in RPET.
Compounded with the shortcomings of conventional refuse containers identified herein is the inability for some materials to be recycled while others are recycled with great abundance. While polyethylene is used in abundance, it is not often recycled. Additionally, polyethylene is not readily biodegradable without special treatment, and therefore it accumulates in landfills. In contrast, other plastic materials are used with wide varieties in consumer products, such as food packaging, and have high recycling rates.
Thus, a heretofore unaddressed need exists in the industry to address the aforementioned deficiencies and inadequacies.
Embodiments of the present disclosure provide high-strength ribbon-woven fabrics constructed of ribbon-woven recycled polyethylene terephthalate (RPET), methods of fabricating such fabrics and disposable bags for containing refuse fabricated using such fabrics. Briefly described, in architecture, one embodiment of the present invention, among others, can be implemented as follows. A high-strength, tear-resistant, puncture-resistant fabric having a high tear strength includes a ribbon-woven fabric having crossed woven ribbons of flat, recycled polyethylene terephthalate (RPET), wherein the RPET may be treated to be substantially free of metallic contaminants. The ribbon-woven fabric sheet may be devoid of low melting temperature bonding layers between the crossed ribbons.
The present disclosure can also be viewed as providing a creating a high-strength ribbon-woven disposable bag. Briefly described, in architecture, one embodiment of the invention, among others, may be implemented as follows. A high-strength, tear-resistant, puncture-resistant bag having a high tear strength, the bag comprising crossed woven flat ribbons, the ribbons including recycled polyethylene terephthalate (RPET), wherein the RPET is treated to be substantially free of metals. The fabric forming the bag may be devoid of low melting temperature bonding layers between the crossed ribbons. The bag may be formed in a sheet and stitched at various edges to prevent unraveling of the bag. The stitch count for the sealing end of the bag may be 100 per inch.
The present disclosure may also be viewed as providing a method of making a high-strength, tear-resistant, puncture-resistant fabric having a high tear strength, the method including forming a sheet from melted recycled polyethylene terephthalate (RPET), wherein the RPET is purified to remove metals, and other impurities, cutting the sheet into ribbons; and weaving the ribbons into a fabric of crossed woven flat ribbons. According to embodiments, the fabric may be devoid of low melting temperature bonding layers between the crossed ribbons. The method may further include forming the fabric into a cylindrical bag having a sealed end. The method may include folding over one end of the bag and stitching the bag to form the sealed end. Also according to embodiments, the stitching may be performed using cotton thread. According to further embodiments, the method may include laminating the fabric with at least one laminate sheet which may include RPET and or polyethylene terephthalate (PET) and according to aspects, the laminate sheet may include an additive, for example a terpolymer such as a terpolymer of ethylene, acrylic ester, and maleic anhydride.
Other systems, methods, features, and advantages of the present disclosure will be or will become apparent to one with skill in the art upon examination of the following drawings and detailed description. It is intended that all such additional systems, methods, features, and advantages be included within this description, be within the scope of the present disclosure.
Many aspects of the disclosure can be better understood with reference to the following drawings. The components in the drawings are not necessarily to scale, emphasis instead being placed upon clearly illustrating the principles of the present disclosure. Moreover, in the drawings, like reference numerals designate corresponding parts throughout the several views.
Rather than utilizing non-disposable barrels and rather than utilizing film bags which resist biodegradation, the subject disclosure is directed to a high strength bag suitable for carting away demolition products such as bricks, wood, nails, and glass is comprised of a woven ribbon structure in which the woven material, rather than being a cord or strand, is a ribbon of recycled polyethylene terephthalate (RPET). In many situations, 100% recycled post-consumer PET, (i.e., RPET) may be used, such as RPET from consumer regrind of beverage bottles, which may include no new or pure plastic. In other situations, RPET with at least one additive may be used. Such additives may include, but are not limited to: a bioplastic, polypropylene, a terpolymer, including a terpolymer which includes ethylene, acrylic ester and maleic anhydride, such as Loader® 4503.
It has been found that, when bags are constructed utilizing the woven ribbon structure, the bags will safely contain refuse weighing in excess of 125 pounds for 40-inch by 29-inch′ bags. It has also been found that any piercing of the woven structure does not creep or otherwise travel due to the woven nature of the fabric or bag, making the fabric or bag both tear resistant and cut resistant, while at the same time providing a tear strength or modulus which is quite high and in one embodiment is 35 warp pounds or 32 filling pounds according to ASTM 5587.
While such a ribbon-woven structure does in fact stretch, it has been found that the bag does not rupture with loading so that the bag may be utilized to contain large amounts of refuse without fear of the bag breaking or failing.
In one embodiment, the fabric or bag is made by melting recycled polyethylene terephthalate pellets, extruding a web that is relatively flat, and then cutting the web longitudinally to make ribbons. These ribbons are then wound up on spools, with the spooled ribbons then feeding a loom or weaving machine such that an under/over weave is produced in which the flat ribbons are clearly visible to the naked eye. It should be noted that bioplastics or other plant-based plastics may be used along with or instead of RPET for fabricating the ribbons. In one embodiment, the recycled polyethylene terephthalate (RPET) ribbons are approximately 2.4 to 6.0 millimeters wide, approximately millimeter thick and are woven in an over and under pattern.
While the weave can be made tight enough to prevent small objects from exiting the bag, in one embodiment a liquid-tight bag is provided by laminating a PET film, or an RPET film to the outer surface of the ribbon-woven bag. The PET film/RPET film may be heat sealed to the web in a laminating process involving placing sheets about the exterior of the bag and laminating such sheets to one or both of the outer surfaces of the bag through a heat/temperature cycle. Thereafter the bag with the laminate may be cooled, for example in a water bath. The laminate sheet may include less than 100% PET or RPET, and may include an additive, such as Loader, ethylene, an acrylic ester, a maleic anhydride-based terpolymer, low density polyethylene, high density polyethylene, etc.
In both the laminated and the non-laminated bag configurations, the structure may be woven in a cylindrical form, after which the bag may be flattened. In order to manufacture each of the individual bags, the cylindrical flattened structure is severed along a transverse cut line and the bag may be folded back on itself at the cut and stitched so as to form the bottom of the bag. The stitching may be done using cotton thread, or alternatively the stitching may be done using PET, RPET or other appropriate material. The unsealed portion of the bag serves as the top or open portion of the bag.
In one example, bags of 40-inches by 29-inches weigh only 85 grams, which make the bags of light enough weight to be folded and packaged in a convenient manner to be opened at a jobsite where the bags will be filled. The bags are intended to be throwaway and packaged folded so that there is no problem of having to provide and store bulky containers.
Approximate ASTM ratings of the bag are set forth in the table below:
(Samples were conditioned and tested in the Standard Atmosphere for Testing Textiles)
Due to the cut resistance, piercing resistance, tear resistance and stretch resistance of the recycled polyethylene terephthalate ribbon-woven bag, bags of the above dimensions are rated to hold upwards of 110 pounds or more of refuse. This means that the bags of the above dimensions may be filled to the top without fear of the bag ripping apart when the bag laden with refuse is transported from one position to another. It has been found that the bags are so tough that construction site refuse may be loaded into the bags without fear of the bags ripping or tearing due to any of the contents within the bag.
The use of recycled polyethylene terephthalate ribbons takes advantage of the physical strength of the recycled, purified polyethylene terephthalate resin when molded and cut into ribbons, with the width of the 1- to 2-millimeter-thick ribbons being variable from six millimeters down to 2.4 millimeters.
While the subject invention is described as utilizing recycled polyethylene terephthalate ribbons, other materials may be utilized for the bag in addition to the RPET, so that the bag may be ribbon-woven from a wide variety of materials, depending on the application. For example, in one non-limiting example, the refuse bags having a 4 mil thickness may be made with a mixture of RPET, titanium dioxide (TiO2) and one or more binders, for non-limiting example, a polypropylene, high density polyethylene, low density polyethylene, an ethylene acrylic ester, etc. In one example, the ratio may include 92-95% RPET with remaining amounts of TiO2 and calcium carbonate as a combined batch along with additive binder(s). As discussed above, the additive may include a terpolymer. This production may be a blown film in circular fashion which may be heat sealed at bottom, or sealed by any appropriate means, including stitching or including a liquid fluid from a pressure pump and elongated into a tube dispensing melted PET/RPET to form a sheet. Similarly, other sealing techniques, such as sonic sealing may also be used. It should be noted that recycled polyethylene terephthalate is a relatively inexpensive material that has the above-noted ASTM properties. Further, polyethylene terephthalate is abundantly recycled from common consumer products, such as beverage bottles. The result is that an ultra-strong fabric or bag can be fabricated with ribbon-weaving techniques and can be manufactured inexpensively enough for the bag to be a one-time use bag and then thrown out.
In summary, an ultra-strong tear resistant, cut resistant, puncture resistant fabric or bag having a high shear strength or modulus is provided by weaving ribbons of flat polyethylene terephthalate sheet into a blanket or a bag. Such a bag may be formed by weaving a cylindrically shaped fabric article, cutting the fabric transversely and sealing up one end to form the bag, e.g., by stitching. The physical properties of the ribbon-woven bag easily accommodate holding refuse including bricks, wood with nails, glass and other refuse in a lightweight disposable bag. In an alternative embodiment, the ribbon-woven bag is overlain with sheets laminated to the exterior of the bag to provide a fluid-tight container.
It will be appreciated that the sharp corners of the brick 16 would ordinarily pierce a polyethylene film bag, as would the points of nail 20 or any other sharp hardware that happens to be contained within the bag. However, it has been found that with a ribbon-woven, recycled polyethylene terephthalate bag structure, all of the refuse at a typical jobsite can be contained safely within a bag formed with the ribbon weaving so that the bag can be a one-use bag which is provided folded up at the jobsite and then opened and filled. Once filled, the bag is generally capable of being lifted by its top and transported to a refuse disposal location.
It will be appreciated that by placing the liquid-tight film over at least one surface of the bag, the bag itself provides for the load-bearing structure, with the outer film containing liquids in the bag.
The present disclosure is also directed to a high-strength ribbon-woven disposable blanket and method of fabrication. The blanket may be constructed from the same materials and largely using the same process as described relative to
In either bag form or blanket form, the product may be used for a variety of purposes. These include trash compactor waste bags, tarpaulins, bulk bags, such as FIBC bags, pallet covers, lumber wrap, house/commercial installation bags as outside coverage, house wrap as labor barrier, or other items which may have similar uses or used under similar conditions.
It should be emphasized that the above-described embodiments of the present disclosure, particularly, any “preferred” embodiments, are merely possible examples of implementations, merely set forth for a clear understanding of the principles of the disclosure. Many variations and modifications may be made to the above-described embodiment(s) of the disclosure without departing substantially from the spirit and principles of the disclosure. All such modifications and variations are intended to be included herein within the scope of this disclosure and the present disclosure.
This application claims priority to co-pending U.S. Provisional Application entitled High Strength Ribbon-Woven Disposable Fabric Articles, having Ser. No. 62/148,974, filed Apr. 17, 2015, which is entirely incorporated herein by reference.
| Number | Date | Country | |
|---|---|---|---|
| 62148974 | Apr 2015 | US |
