Abstract:
A cap for sealing a container having a neck includes an annular outer skirt having an inner surface and an outer surface, a top portion of the outer skirt forming an annular rim. A generally concave top wall extends inwardly from and below a plane defined by the rim, the top wall having a top face and a bottom face. An annular inner skirt extends downward from the top wall bottom face and disposed radially inward from and concentric with the outer skirt, wherein the inner skirt is configured to sealingly engage with an inner surface of the container neck when the cap is attached thereto.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
       [0001]    This application is a continuation of U.S. patent application Ser. No. 12/476,475, filed Jun. 2, 2009, which claims the benefit of U.S. provisional application Ser. No. 61/099,328 filed Sep. 23, 2008, all of which are incorporated by reference herein. 
     
    
     BACKGROUND OF THE INVENTION 
       [0002]    1. Field of the Invention 
         [0003]    This invention relates to a cap for sealing a containers, such as a bottle. 
         [0004]    2. Background Art 
         [0005]    Bottles or other containers intended to contain liquids require a cap that is capable of establishing a seal of the container which is effective to prevent leakage of the liquids contained therein. In some prior bottles, an internal foam closure of liner is disposed on an underside of the bottle cap in a secondary process. As such, use of a foam liner introduces additional material and labor into the construction of the bottle cap. In addition, in the event that the foam liner becomes compromised, the sealing capabilities of the foam liner can be adversely affected, potentially resulting in leakage of the liquid contents. Leakage can also occur as a result of internal pressure changes in the container, such as can be introduced during freezing and subsequent thawing of the liquid contents, which adversely affect the seal between the foam liner and the container. 
         [0006]    As a tamper-evident measure, bottles and other containers are often packaged with a plastic shrink sleeve extending at least partially over the container closure and downward onto the container itself. Unfortunately, these shrink sleeves can often be very difficult for a consumer to remove in order to open the container and gain access to the product therein. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0007]      FIG. 1  is a perspective view of a bottle cap according to the present invention; 
           [0008]      FIG. 2  is a top plan view of an interior of a bottle cap according to the present invention; 
           [0009]      FIG. 3  is a perspective view of the interior of a bottle cap according to the present invention; 
           [0010]      FIG. 4  is a cross-sectional view of a bottle cap according to the present invention taken along line  4 - 4  of  FIG. 1 ; and 
           [0011]      FIG. 5  is a cross-sectional, partially cut away view of a bottle cap denoting exemplary dimensions in accordance with an aspect of the present invention. 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0012]    As required, detailed embodiments of the present invention are disclosed herein; however, it is to be understood that the disclosed embodiments are merely exemplary of the invention that may be embodied in various and alternative forms. The figures are not necessarily to scale, and some features may be exaggerated or minimalized to show details of particular components. Therefore, specific structural and functional details disclosed herein are not to be interpreted as limiting, but merely as a representative basis for teaching on skilled in the art to variously employ the present invention. 
         [0013]    According to an aspect of the present invention, a leak-proof closure for a container is provided which also facilitates easier removal of tamper-evident sealing means on the exterior of the container. With reference to  FIG. 1 , a bottle cap in accordance with an aspect of the present invention is illustrated and designated generally by reference numeral  10 . The bottle cap  10  may be used for sealing a container (not shown), such as a bottle, having a neck. The container may hold a liquid substance which, according to one non-limiting aspect of the present invention, may be a liquid energy supplement or an energy drink. Such a liquid energy supplement or energy drink may contain one or more of the following ingredients: niacin, vitamin B6 (e.g., as pyridoxine hydrochloride), folic acid, and vitamin B12 (e.g., as cyanocobalamin), taurine, glucuronolactone, malic acid, N-acetyl L-tyrosine, L-phenylalanine, caffeine, and citicoline. 
         [0014]    Referring again to  FIG. 1 , as well as to  FIGS. 2-5 , bottle cap  10  has a generally circular top wall  12  having a top face  14  and a bottom face  16 . An annular outer skirt  18  having an outer surface  20  and an inner surface  22  depends downwardly from the outermost periphery of the top wall  12 . The outer surface  20  may be ribbed, as shown in  FIGS. 1 and 5 , for easier gripping by the consumer. The inner surface  22  includes a threaded portion  24 , which may have a standard helical configuration, arranged to cooperate with a correspondingly shaped threaded portion on an exterior of the container neck (not shown) in order to secure the bottle cap  10  to the container. Of course, other means for attaching the bottle cap  10  to the container are also fully contemplated. According to a non-limiting aspect of the present invention, as depicted in  FIG. 5 , an outer diameter of the bottle cap  10  may be approximately 0.9 inches, an inner diameter of the bottle cap  10  between the outer skirt inner surfaces  22  may be approximately 0.8 inches, the height of the bottle cap  10  may be approximately 0.6 inches, and the length of the outer skirt  18  to the top wall bottom face  16  may be approximately 0.5 inches. Of course, it is understood that the bottle cap  10  according to the present invention is not limited to these absolute or relative dimensions. 
         [0015]    The bottle cap  10  further includes an annular inner skirt  26 , or plug, as depicted in  FIGS. 2-5 , arranged to sealingly engage within the inner diameter of the container neck. Inner skirt  26  also depends downwardly from the top wall  12 , set radially inward from the outer skirt  18  in concentric relation thereto. The inner skirt  26  also may act to guide the bottle cap  10  into position on the container, and may include a taper, as best shown in  FIG. 5 , which may further facilitate locating and inserting the inner skirt  26  with respect to the container neck. According to a non-limiting aspect of the present invention, as depicted in  FIG. 5 , an outer diameter of the inner skirt  26  may be approximately 0.6 inches, an inner diameter of the inner skirt  26  may be approximately 0.03 inches, and depth of the inner skirt  26  may be approximately 0.04 inches. Therefore, the inner skirt  26  may have a length of about 20% of the length of the outer skirt  18 . Again, it is understood that the bottle cap  10  according to the present invention is not limited to these absolute or relative dimensions. 
         [0016]    When the bottle cap  10  is fitted onto the container, the inner skirt  26  contacts an inner surface of the container neck which abuts the top wall bottom face  16 , such that the container neck is tightly received between the outer and inner skirts  18 ,  26 , thereby sealing the container and impeding the loss of fluid therefrom. A tight interference fit may be created by properly sizing the inner skirt  26  and the container neck inner diameter in order to prevent the liquid contents of the container from leaking, even under conditions such as freezing/thawing which induce internal pressure changes in the container. 
         [0017]    In further accordance with an aspect of the present invention, the bottle cap  10  may be injection molded and have a one-piece construction formed from a plastic material. According to one aspect of the present invention, the bottle cap  10  may be constructed from polypropylene, or from a co-polymer of polypropylene and ethylene propylene. The addition of ethylene propylene to the base polypropylene material may reduce brittleness and increase impact resistance of the bottle cap  10 . Of course, it is understood that other materials are also contemplated for the construction of bottle cap  10 . 
         [0018]    Ingredients specific to liquid energy supplements or energy drinks (these terms used interchangeably herein), such as vitamin B6, vitamin B12, and folic acid, may oxidize and subsequently undergo an unappealing color change. When prior art foam liners are used for sealing purposes, soaking of the liquid into the edges of the foam liner may result in oxidation, with the residue appearing as a dark substance which is typically unappealing to a consumer. Use of the bottle cap  10  with inner skirt  26  according to the present invention eliminates this problem encountered with liquid energy supplements or energy drinks. In addition, the plastic material used for construction of the bottle cap  10  offers a much higher level of impermeability to oxygen than does open cell foam used in prior art foam liners, such that the shelf life of the liquid energy supplement or energy drink can be extended. 
         [0019]    With reference to FIGS.  1  and  4 - 5 , according to one aspect of the present invention, top wall top face  14  may be generally concave and outer skirt  18  may include an annular rim  28  extending upwardly from the top face  14  around the perimeter of the top wall  12 . In accordance with one non-limiting aspect of the present invention, a distance from a plane defined by the rim  28  to the top face  14  may vary from approximately 0.095 inches near the rim  28  to approximately 0.105 inches at or near the center of the top wall  12  to the plane defined by the rim  28  may be about 10%, 15%, or 20% of the overall height of the bottle cap  10 . However, it is understood that the bottle cap is not limited to these absolute or relative dimensions. It is also understood that the term “concave” as used herein is not restricted to describing a surface with a constant radius of curvature, but rather is used to denote the general appearance of the surface. 
         [0020]    In one embodiment, the concavity of the top wall  12  spans about 80%, 85%, or 90% of the diameter of the bottle cap  10 , although other proportions are also contemplated. The concavity of the top face  14  allows the shrink sleeve to span partially across the concavity, and is of sufficient diameter to offer an avenue for a finger or fingernail of a consumer to gain easier access to an edge of the shrink sleeve on the bottle cap  10 . The size of the concave top face  14  also provides an ergonomic surface which cooperates with the natural curve of a consumer&#39;s finger to aid in removing the shrink sleeve packaging. 
         [0021]    With continuing reference to FIGS.  1  and  4 - 5 , the rim  28  may serve several purposes. As described above, one purpose may be to exaggerate the height difference between the shrink sleeve and the concavity of top face  14 , allowing a consumer easy access to the edge of the shrink sleeve to facilitate its removal. A second purpose of the rim  28  may be to reinforce the bottle cap  10  to resist breakage should the container be dropped or the cap  10  otherwise impact a hard surface. A minimal amount of plastic material is required for construction of the rim  28 , which produces a light yet strong bottle cap  10 . In one embodiment, the rim  28  may have a thickness of about 10% or 15% of the diameter of the bottle cap  10 , although other proportions are also contemplated. Maintaining a lightweight bottle cap  10  is cost effective and promotes fast cycle times during the injection molding process. Still further, the combination of the rim  28  and the steepness of its angled connection with the concave top face  14  create a unique “shadow box” effect to highlight any indicia provided on the top face  14 , such as a logo  30  as depicted in  FIG. 1 . A consumer&#39;s eye may be drawn, to the recessed logo  30  and the contrast between the logo  30  and the background, and thus this configuration may create a unique, three-dimensional brand identity. Of course, it is understood that the specific logo  30  depicted herein is purely exemplary, and that other logos or indicia are fully contemplated according to the present invention. 
         [0022]    While aspects of the invention have been illustrated and described, it is not intended that these aspects illustrate and describe all possible forms of the invention. It is understood that the features of various implementing aspects may be combined to form further aspects of the invention. The words used in the specification are words of description rather than limitation, and it is understood that various changes may be made without departing from the spirit and scope of the invention.