Abstract:
A beverage container includes a recyclable, multilayered, polymer bottle covered by an ultraviolet-absorbent, biodegradable and removable overlay. The container is thus both suitable for light sensitive products, such as beer, and ecologically sound in design for recycling. In one embodiment the bottle is a polyethylene terephthalate bottle covered by a biodegradable plastic, upon which has been printed various materials desired by the producer or consumer. The biodegradable plastic is removed by the consumer before disposal to facilitate the recycling process.

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
       [0001]    This application claims the benefit of U.S. provisional application 61/560,982 filed Nov. 17, 2011 and entitled: “Ultraviolet-Blocking Recyclable Plastic Container” hereby incorporated in its entirety by reference. 
     
    
     BACKGROUND OF THE INVENTION 
       [0002]    The present invention relates generally to a plastic bottle, for example, a soda bottle or beer bottle, providing improved blocking of ultraviolet light which may adversely affect the bottle&#39;s contents. In particular, the invention provides a bottle balancing consumer desire to be ecologically responsible with the desire to obtain a high-quality product for a reasonable price. 
         [0003]    In the beverage industry, cost-saving and safety considerations have driven many companies towards the use of plastics instead of glass as the material for the production of bottles. There has also been an increasing need from consumers for bottling that is convenient, lightweight, unbreakable, and recyclable, for example, for consumption at a picnic or sporting event. 
         [0004]    Some beverages, such as beer, are easily ruined if the packaging does not meet certain criteria. For instance, beer can lose its carbonation over time by carbon dioxide molecules that migrate outward through the bottle wall. At the same time, oxygen molecules diffuse into the beverage from the outside, producing off-flavors and affecting foam stability. A beer&#39;s flavor can also be ruined by exposure to ultraviolet (UV) light, which causes the light to act on certain chemicals in humulus lupulus or hops (a common bittering agent in beer) making the beer taste “skunky”. 
         [0005]    While plastic is not inherently gas impermeable or UV-absorbent/blocking, recent innovation has created polymers or combinations of polymers having properties that are suitable to store products such as beer. Unfortunately, these polymers are not necessarily recycling-friendly and in particular, some colors of plastic (for example, UV blocking brown or green) cannot be recycled using the current recycling infrastructure. 
       SUMMARY OF THE INVENTION 
       [0006]    The present invention provides a UV-absorbent/blocking, polymer container that uses a thin biodegradable overlay that is preferably removed before recycling to be more amenable to the current recycling process. In one embodiment, the plastic bottle is made of multiple polymer layers fused together to provide a gas impermeable polymer laminate. The polymer laminate is surrounded by a biodegradable UV-absorbent shrink-wrap that is removed by the user and disposed separately from the polymer laminate. The shrink-wrap is expected to degrade naturally while the plastic bottle is recycled under the current recycling infrastructure. 
         [0007]    Specifically, in one embodiment the present invention provides a foundation vessel with a base sized to support the container against a substantially flat horizontal surface and surrounded by a sidewall extending upwardly along an axis and terminating at a lip defining the container volume. A UV blocking thermoplastic film conforms substantially to the upwardly extending sidewalls of the foundation vessel and is removably attached thereto. 
         [0008]    It is thus a feature of at least one embodiment of the invention to provide for a container that has a removable UV blocking film to protect its contents from UV exposure and subsequent spoilage. 
         [0009]    The foundation vessel may be a recyclable plastic material. 
         [0010]    It is thus a feature of at least one embodiment of the invention to provide a container that is recyclable and environmentally friendly. 
         [0011]    The foundation vessel may be multilayered. 
         [0012]    It is thus a feature of at least one embodiment of the invention to provide a gas impermeable barrier to prevent diffusion of gases into or out of the bottle. 
         [0013]    The UV blocking thermoplastic film may include a UV blocking dye. 
         [0014]    It is thus a feature of at least one embodiment of the invention to easily transform a transparent plastic into a UV blocking film by adding the dye. 
         [0015]    The UV blocking thermoplastic film may be biodegradable. 
         [0016]    It is thus a feature of at least one embodiment of the invention to have a film that is environmentally friendly and does not leave behind waste. 
         [0017]    The UV blocking thermoplastic film may be a heat shrinkable film. 
         [0018]    It is thus a feature of at least one embodiment of the invention to provide a film that can conform to the shape of the container and removably adhere to the container without requiring adhesives. 
         [0019]    The UV blocking thermoplastic film may be perforated to promote a tearing of the film for complete removal by the consumer. 
         [0020]    It is thus a feature of at least one embodiment of the invention to facilitate removal of the film so that the foundation vessel can be more easily recycled without the film. 
         [0021]    The container may have a cap which encloses the opening of the foundation vessel defined by the radial circumference of the lip and the heat shrinkable film extends partially over the cap. 
         [0022]    It is thus a feature of at least one embodiment of the invention to use the film as an anti-tampering method and to encourage the consumer to remove the entire film upon opening of the cap. 
         [0023]    The UV blocking thermoplastic film may be polyactic acid/polylastide (PLA). 
         [0024]    It is thus a feature of at least one embodiment of the invention to provide a film that has high clarity and gloss and easy processability in most equipment. 
         [0025]    The UV blocking thermoplastic film may be polyhydroxyalkanoates (PHA). 
         [0026]    It is thus a feature of at least one embodiment of the invention to provide a film that can degrade aerobically and anaerobically and has easy processability in most equipment. 
         [0027]    The UV blocking thermoplastic film may have printed material on either or both sides. 
         [0028]    It is thus a feature of at least one embodiment of the invention to allow space for product advertising and promotion and/or to encourage the consumer to remove the film before recycling the container. 
         [0029]    Other features and advantages of the invention will become apparent to those skilled in the art upon review of the following detailed description, claims and drawings in which like numerals are used to designate like features. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0030]      FIGS. 1   a - b  are respectively a perspective view of a plastic-wrapped polymer bottle of one embodiment of the invention cut away to reveal the laminations of the bottle walls and an enlarged cross-sectional view showing four layers of the lamination, the interior-most first layer of which is a first polymer, the next outward layer being a variation of that polymer, the third outward layer being made of the same polymer as the first layer, these layers fused together, and the fourth and outermost layer being a thin removable overlay, such as a plastic shrink-wrap material; 
           [0031]      FIG. 2  is a simplified flow diagram of a manufacturing process for the bottle of  FIG. 1  in which a bottle comprising the first three fused layers is surrounded by a cylinder of plastic wrap with open top and bottom, and in which the plastic wrap is then shrunk using heat until it conforms to the shape of the bottle; 
           [0032]      FIG. 3  is a cross-sectional view of the fused layers in  FIG. 1  before application of the shrink wrap layer showing impermeability of these layers to a carbon dioxide molecule located on the interior of the bottle and an oxygen molecule located on the exterior of the bottle; 
           [0033]      FIG. 4  is a cross-sectional view of the layers of  FIG. 3  further including a removable UV-blocking overlay where UV rays from the exterior of the bottle are absorbed by the overlay before they reach the interior fused layers; 
           [0034]      FIG. 5  is a perspective view of a bottle similar to that of  FIG. 1  showing a design printed on the shrink wrap and a pattern of perforations running in a ring around the cap portion of the plastic wrap and then spiraling down through the neck and body portions of the plastic wrap; and 
           [0035]      FIG. 6  is a plastic wrap covered bottle where the plastic wrap has been partially removed, revealing a cylindrical twist-off cap and additional optional printed material on the interior of the plastic wrap. 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
       [0036]    Referring now to  FIG. 1 , in one embodiment, the walls of a plastic-covered polymer bottle  10  with a cylindrical base portion and a tapered neck leading up to a cap, such as the type of bottle commonly used for beer, may comprise four distinct layers. 
         [0037]    As shown in cross-section  12 , the innermost polymer layer  14  may be a transparent, food-grade polymer, such as virgin polyethylene terepthalate (PET). PET is commonly used to bottle carbonated beverages because it provides good alcohol and essential oil barrier properties, generally good chemical resistance, and a high degree of impact resistance and tensile strength, making it a versatile option for bottling contents. Other common bottling polymers may be used, such as virgin polyethylene naphthalate (PEN), virgin polyvinyl chloride (PVC), virgin high density polyethylene (HDPE), or virgin low density polyethylene (LDPE). 
         [0038]    Lying exterior to the polymer layer  14  is a polymer layer  16  comprising a post consumer recyclate (PCR), for example, a recycled variation of the polymer used in polymer layer  14 , such as post-consumer PET. It is appreciated that the PCR may be any of a number of suitable plastics that have served their intended purpose and have been diverted or recovered from the waste stream. This would include PCR from closed-looped recycle systems which recycle a single type of plastic into the same production process, such as virgin PET bottles recycled into post-consumer PET bottles. 
         [0039]    Lying exterior to polymer layer  16  is another polymer layer  14 , which “locks in” the recycled polymer layer  16 . This layer may be the same material as the first polymer layer  14 , for example, virgin PET, or may be another polymer material. 
         [0040]    These three layers are fused together to be inseparable by the consumer and are referred to collectively as polymer laminate  20  and make up the structural part of the bottle walls of a foundation vessel. Polymer laminate  20  is recyclable using current recycling infrastructure, as would be the case if virgin PET and post-consumer PET were used. Generally, the polymer laminate  20  may, in one embodiment, meet the requirements of recyclability in the FTC “Green Guides” as of the date of this filing, hereby incorporated in its entirety by reference. 
         [0041]    It is appreciated that multilayer bottles may encompass any combination of polymer or polymer blend layers. Examples of polymer blends with effective transmission barriers include poly(ethylene naphthalate) (PEN)/PET blends, liquid crystalline polymers (LCP)/PET alloys, or nylon MXD6/PET blends and clay/PET mixtures. Other effective polymer layers include co-polymer ethylene vinyl alcohol (EVOH) or crystalline polyamide resin nylon MXD6. Multilayer bottles may also include an oxygen scavenger used as an active layer to absorb oxygen molecules that migrate into the bottle, into the beverage, or into the headspace of the bottle. This is done by oxidation of the iron powder contained in the oxygen scavenger and absorption of oxygen molecules. 
         [0042]    It is appreciated that the order of the polymer layers may vary and may be characterized by any denomination of layered structures, such as three, four, five or more layers, and may be repeated any number of times. 
         [0043]    Other methods besides multilayer bottling may be employed to prevent carbon dioxide egress and oxygen ingress, such as bottle coatings or barrier-enhanced monolayer bottles. The inside and/or outside of the bottle may be coated with an agent that creates a barrier to the migration of oxygen and carbon dioxide, for example, organic coatings such as epoxyamine. Or for processing simplicity, a single layer may be desired and a barrier resin and/or oxygen scavenger may be blended with PET to produce an effective monolayer structure. It is appreciated that other methods of bottle coating or compositions of monolayer bottles may be used. 
         [0044]    Exterior to this polymer laminate  20  is a consumer removable, UV-absorbent, biodegradable overlay  18 . This removable overlay  18  is in the preferred embodiment a plastic shrink-wrap and covers all outer surfaces of the bottle that might be exposed to light in typical use. In one embodiment, the overlay  18  may be a biodegradable plastic, such as polylactide (PLA), that is a thermoplastic aliphatic polyester derived from renewable resources which can biodegrade under certain conditions, such as in the presence of oxygen, but is difficult to recycle. In an alternative embodiment, the overlay  18  is polyhydroxyalkanoates (PHA), that is a linear polyester that accumulates in a wide variety of microorganisms and is fully biodegradable aerobically or anaerobically in the presence of natural microbes, e.g., in septic systems, commercial waste water treatment systems, composting environments or even cold waters. It is also appreciated that other biodegradable plastic may be used, such as other polyesters, (bio)polyesters, or starch-based polymers which have biodegradable properties. It is also appreciated that other biodegradable plastics may also be used. In one embodiment a biodegradable film that will decompose into carbon dioxide and water in a “controlled composting environment” will be selected. In one embodiment the biodegradable film will meet at least one of the standards of: ASTM D6400: a test to certify if a product can be composted, ASTM D6868: a test to determine if a biodegradable plastic is truly biodegradable, and EN 13432 a European test to determine biodegradability of plastics. Other embodiments may meet any of ASTM D5511-12 Standard Test Method for Determining Anaerobic Biodegradation of Plastic Materials Under High-Solids Anaerobic-Digestion Conditions or ASTM D5526-12 Standard Test Method for Determining Anaerobic Biodegradation of Plastic Materials Under Accelerated Landfill Conditions. 
         [0045]    A UV blocking agent such as “CESA-Natur Light” manufactured by Clariant of Glattbrugg Switzerland, making use of naturally occurring UV blocking aromatics or other UV blocking material may be added to the PLA. Other UV-absorbing/blocking shrink wrapping films or blocking dyes may also be used. Ideally, the amount of UV blocking will be comparable to amber glass used in a standard beer bottle, providing, for example, a reduction in intensity for ultraviolet light in the range of 280 to 380 substantially in excess of the clear plastic bottle. In some embodiments, the amount of UV blocking at 403 nanometers will be greater than 25 percent or alternatively at least equal to 50 percent, or alternatively greater than 80 percent. 
         [0046]    Referring now to  FIG. 2 , in one embodiment, the manufacture of the product may be divided into three steps. In the first step  21 , a cylinder of plastic wrap  22 , which is open on the top and bottom ends, is placed to concentrically surround the polymer bottle  24 . The size of the plastic wrap  22  is determined by the shrinkage rate of the plastic. In the second step  23 , the cylinder of plastic wrap  22  is deformed by shrinkage around the polymer bottle  24  by means of heating, represented as  26 , for example, by a heat gun or by passing the polymer bottle  24  through a heat tunnel or conveyor. If using a heat gun, the heat source should be moved around the entire area of the polymer bottle  24  to shrink the plastic wrap  22  evenly. In the final step  25  the plastic wrap  22  is fully shrunk and deformed to snuggly cover the polymer bottle  24 , the plastic wrap  22  is allowed to cool, and the plastic-covered polymer bottle  10  is formed. The cylinder of plastic wrap  22  may be mono-directional in shrinkage to shrink preferably in its circumference but not height. 
         [0047]    Referring now to  FIG. 3 , the polymer layer  20  provides not only structural strength, but a structure that is impermeable to gas. For a carbonated beverage, it is desired that carbon dioxide  30  molecules remain in the interior of the container, and the carbon dioxide  30  cannot pass through the polymer layer  20  to get to the exterior. From the other direction, oxygen  28  molecules cannot pass through the polymer layer  20  to the interior of the container, as for certain beverages such as beer, oxygen can spoil the taste of the beverage. 
         [0048]    Referring now to  FIG. 4 , the overlay  18  is UV-absorbent. UV-rays  32  from the exterior of the container are absorbed by overlay  18  before they can reach polymer layer  20 , and reemitted as heat by the bonds in the material used to create the overlay  18 . Generally, the overlay  18  need not be recyclable, as it may be removed as described below, allowing the principle components of the bottle to be recycled and the overlay disposed of by other means. 
         [0049]    Referring now to  FIG. 5 , perforations may be placed on the plastic wrap layer that encourage the consumer in the complete removal of said layer. In particular, removal of the cap may require beginning a tearing of the perforations. It is desired that the plastic wrap be removed before bottle recycling because the plastic wrap may be a contaminate to the post consumer recyclate, causing problems such as substantial loss of intrinsic viscosity, color issues, loss of clarity/haze, extruder drool or drip, or black specks. 
         [0050]    In one embodiment, perforation  36  forms a partial ring around the cap portion  35  of the bottle so that a torsional force as one uses to twist off a bottle cap may be used to begin the tearing of the perforations  36 . Continuous from perforation  36  is perforation  38 , which spirals down the remaining neck and body portion of the plastic wrap that covers the bottle. Once the tearing is started at perforation  36  it will naturally continue down perforation  38 , promoting a complete removal of the plastic wrap. The plastic wrap may have a design  34  printed on it, such as the logo of the beverage company, a description, nutritional information, or other such necessary or desirable material. As the cap portion  35  is entirely covered by plastic wrap except at the very top, the plastic wrap acts as a means of tamper-resistance, as the bottle cannot be opened without tearing it along the perforations. Further, use of the bottle requires at least partial removal of the plastic wrap and hopefully encourages complete removal for recycling. Printed instructions promoting removal of this plastic wrap layer may be included on the plastic wrap. Even partial removal of the plastic wrap layer may be sufficient to promote its eventual separation from the bottle by abrasion in transport to a recycling center or subsequent mechanical removal steps that may lightly abrade the outer surface of the bottle by tumbling, brushes, or the like. 
         [0051]    Referring now to  FIG. 6 , the overlay  18  is removable from the exterior of the bottle, and may be discarded along with regular trash, as it may be biodegradable, a quality promoted by its thinness and thus high surface area to volume. Thus removed, the transparent polymer layer  20  and twist-off cap  40  are revealed. The twist-off cap need not have a tamper-resistant sealing ring, as the overlay  18  is sufficient for sealing and tamper-resisting needs. Also revealed, on the interior surface of the overlay  18 , is additional printed material, which could be information on a contest, advertising, or any other desirable material that might further promote complete removal of the plastic wrap layer. 
         [0052]    Certain terminology is used herein for purposes of reference only, and thus is not intended to be limiting. For example, terms such as “upper”, “lower”, “above”, and “below” refer to directions in the drawings to which reference is made. Terms such as “front”, “back”, “rear”, “bottom” and “side”, describe the orientation of portions of the component within a consistent but arbitrary frame of reference which is made clear by reference to the text and the associated drawings describing the component under discussion. Such terminology may include the words specifically mentioned above, derivatives thereof, and words of similar import. Similarly, the terms “first”, “second” and other such numerical terms referring to structures do not imply a sequence or order unless clearly indicated by the context. 
         [0053]    When introducing elements or features of the present disclosure and the exemplary embodiments, the articles “a”, “an”, “the” and “said” are intended to mean that there are one or more of such elements or features. The terms “comprising”, “including” and “having” are intended to be inclusive and mean that there may be additional elements or features other than those specifically noted. It is further to be understood that the method steps, processes, and operations described herein are not to be construed as necessarily requiring their performance in the particular order discussed or illustrated, unless specifically identified as an order of performance. It is also to be understood that additional or alternative steps may be employed. 
         [0054]    It is specifically intended that the present invention not be limited to the embodiments and illustrations contained herein and the claims should be understood to include modified forms of those embodiments including portions of the embodiments and combinations of elements of different embodiments as come within the scope of the following claims. All of the publications described herein, including patents and non-patent publications, are hereby incorporated herein by reference in their entireties.