Abstract:
Biodegradable novelty packages, which can take the shape of eggs (i.e., ellipsoids), for example, are useful for containing small toys, candy or the like. Such small toys, candy and the like are often hidden in petroleum-based plastic eggs for children&#39;s amusement. Biodegradable novelty packages as described herein are formed of a biodegradable resin, such as a biodegradable thermoplastic.

Description:
RELATED APPLICATION 
     The present application claims priority to U.S. Provisional Patent Application Ser. No. 61/386,238, filed Sep. 24, 2010 and titled, “BIODEGRADABLE NOVELTY PACKAGE,” which is commonly assigned and incorporated by reference herein in its entirety. 
    
    
     TECHNICAL FIELD 
     The present disclosure relates generally to biodegradable novelty packages and, in particular, in one or more embodiments, the present disclosure relates to compostable plastic eggs. 
     BACKGROUND 
     A common Easter tradition involves Easter egg hunts, where colored eggs are hidden for children to find. This tradition has generally evolved away from the use of real eggs, and has instead gravitated toward the use of colored plastic eggs. These petroleum-based plastic eggs are typically two-part packages, that can be filled with small toys, candy and the like. Similarly, in another Easter tradition, Easter baskets are often presented to children containing such colored plastic eggs, again typically filled with small toys, candy and the like. Such use generates a large amount of plastic waste, resulting in significant waste of petroleum resources. While people have looked to ways of repurposing these plastic eggs, such as using them in children&#39;s play kitchens, or in the creation of Easter wreaths using them as decorations, a significant portion of these plastic eggs are likely to end up in landfills or incinerators. 
     For the reasons stated above, and for other reasons stated below which will become apparent to those skilled in the art upon reading and understanding the present specification, there is a need in the art for alternatives to traditional plastic eggs. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1A  is a view of a package in accordance with an embodiment of the disclosure. 
         FIG. 1B  is a cross-sectional view of the package of  FIG. 1A  in accordance with an embodiment of the disclosure. 
         FIG. 1C  is an expanded view of a portion of the cross-sectional view of  FIG. 1B  in accordance with an embodiment of the disclosure. 
     
    
    
     DETAILED DESCRIPTION 
       FIG. 1A  depicts a package  100 . The package  100  is a novelty package. For example, the package  100  may be egg-shaped (e.g., an ellipsoid) as depicted, such as might be used to enclose small toys, candy or the like. Alternatively, the package  100  may be some other shape, such as a sphere, a polyhedron or some other three-dimensional regular or irregular shape. The package  100  includes two or more portions defining sidewalls of the package  100 , each configured to mate with at least one other of the two or more portions. 
     In the example of  FIG. 1A , the package  100  includes a first portion  105  having sidewalls  115 . The package  100  further includes a second portion  110  having sidewalls  120 . The sidewalls may have, for example, a thickness of 0.05 inches (1.25 mm) to 0.1 inches (2.5 mm) or more. The package  100  has a height  125 , e.g., 2.97 inches (75 mm). 
       FIG. 1B  is a cross-sectional view of the package  100  taken along line A-A of  FIG. 1A . The package  100  has a width  130 , e.g., 2.25 inches (57 mm). In the case of the example ellipsoid package  100 , or in the case of a spherical package or the like, the width  130  may also represent a diameter (e.g., a maximum exterior diameter) of the package  100 . The single layer sidewalls  115  and  120  of the first and second portions  105  and  110 , respectively, define a hollowed interior of the package  100 . 
       FIG. 1C  is expanded view of cut-out B of  FIG. 1B  showing more detail of one example mating configuration for the first portion  105  to the second portion  110 . As shown in  FIG. 1C , the sidewall  115  (of first portion  105 ) includes a rim  135  having an outwardly-facing (i.e., facing toward the exterior of the package  100 ) flange  140 , while the sidewall  120  (of second portion  110 ) includes a rim  145  having an inwardly-facing (i.e., facing toward the interior of the package  100 ) flange  150 . The flange  140  and the flange  150  are configured to snap together, such as through flexure of one or both of the rims  135  and  145 . This permits the package  100  to be opened (i.e., taken apart) and closed (i.e., reassembled) more than once. Other embodiments could utilize a simple pressure-fit connection, i.e., without snap-fit flanges as shown in  FIG. 1C . For example, an inner diameter of rim  135  could be substantially equal (e.g., equal) to an outer diameter of rim  145  such that simple friction could be used to releasably hold the two portions  105  and  110  together. The flange  140  and  150  is most effectively placed at a joint in a circular cross section of the ellipsoid. 
     The package  100  is a biodegradable novelty package. The portions  105  and  110  of the package  100  are formed of a biodegradable resin, e.g., a biodegradable thermoplastic. 
     Applicant notes that a biodegradable resin should have sufficient rigidity to form a novelty package of the type described herein while being sufficiently flexible to form a self-closure, such as a snap-fit or pressure fit closure of the type described herein, and without being brittle to the point of raising safety concerns; sufficient strength to facilitate thin-walled construction of the package; sufficient stability to be warehoused and displayed on retail shelves for extended periods, as well as sufficient stability to contain candies and other foodstuffs and to endure environments in which the package may be likely to be placed in use; and the ability to incorporate colorants. As one example, Applicant has identified PLA (polylactic acid)-based resins as suitable biodegradable resins. PLA can be made from renewable resources, such as corn starch or sugars. PLA can be 100% compostable and it can be shelf stable until subjected to heat, moisture and microorganisms typically found in a compost. Applicant has further identified certain physical characteristics that appear to meet these criteria for PLA-based resins. For example, a PLA-based resin having a Crystalline Melt Temperature of approximately 160-170° C., a Glass Transition Temperature of approximately 55-65° C., a Tensile Yield Strength of approximately 7,000 psi (48 MPa), a Tensile Elongation of approximately 2.5%, a Notched Izod Impact of approximately 0.3 ft-lb/in (0.16 J/m), a Flexural Strength of approximately 12,000 psi (83 MPa), and a Flexural Modulus of approximately 555,000 psi (3828 MPa) appears to meet Applicant&#39;s criteria. Applicant notes that other physical characteristics may also meet the criteria. 
     One specific example of a PLA-based thermoplastic for use in the package  100  is Biopolymer 3251D, available through NatureWorks (Minnetonka, Minn., USA). The Biopolymer 3251D is a thermoplastic, capable of use for forming the package  100  using injection molding techniques. The Biopolymer 3251D is compostable, and has the rigidity, strength, flexibility and ability to incorporate colorants to form a novelty package, such as a plastic egg. 
     Applicant notes that a variety of biodegradable resins fail to meet these criteria established by Applicant. Not all biodegradable plastics are colorable or rigid enough to be used for items such as plastic eggs. Some biodegradable resins lack sufficient stability. For example, some biodegradable plastics break down merely upon contact with water or with excessive heat or may simply break down primarily based on its age. 
     In addition to PLA-based thermoplastic, the portions of the package  100  may contain additional chemical components that do not materially affect the basic and novel properties of the package  100  disclosed herein. For example intentional additions, such as colorants, or unintentional additions, such as low-level contaminants common in industrial environments, may be contained within its portions without materially affecting its basic and novel properties. 
     CONCLUSION 
     Biodegradable novelty packages are described herein. The biodegradable novelty packages are formed of a biodegradable resin. Such packages can be used, for example, as plastic Easter eggs or the like. These biodegradable novelty packages would not only reduce the use of petroleum resources, they would reduce the strain on landfills or incinerators, and the pollution associated therewith.