Abstract:
A container suitable for containing a liquid composition and comprising an insert located in the neck of said container, and wherein when said container is filled with a liquid composition, zero headspace exists below said insert.

Description:
CROSS REFERENCE TO RELATED APPLICATION 
       [0001]    This application claims the benefit of U.S. Application Ser. No. 60/963,870 filed Aug. 7, 2007. 
     
    
     FIELD OF THE INVENTION 
       [0002]    The present invention relates generally to a container having zero headspace. More specifically, the present invention relates to an insert which achieves zero headspace within the container. 
       BACKGROUND OF THE INVENTION 
       [0003]    As liquid compositions are packaged into consumer ready packages, air is commonly trapped at the top of the container before it can be sealed. The air trapped at the top of the container (headspace) results in an air bubble, which disrupts the composition within the bottle if the bottle is rotated or its orientation is changed. In instances where a specific design is created within the liquid composition in the container, the air bubble can cause damage to the design during shipping. Headspace can generally be reduced by “topping off” the container with a sufficient amount of the composition as to prevent air from remaining at the top of the container. However, this technique is difficult to automate, and therefore must typically be performed by hand. Additionally, “topping off” often results in overflow of the liquid composition, which becomes costly and risks overall quality of the liquid product in the container. 
         [0004]    A known method for eliminating headspace is to vent liquid-filled containers. One technique involves a pressure system comprising pieces of rubber, metal springs, and/or soft films (typically vinyl chloride) being used to lift and open vent orifices in a closure when internal pressure reaches a given threshold value. The venting method is heavily dependent on the type of liquid composition being vented in order to be operable. It also limits design options and prevents optimal dispensing of the liquid composition. Another technique is to provide elaborate passages in a closure whereby gases may leave the system but liquid losses are minimized. A third system, which may be called the pinorifice system, employs one or more tiny orifices in rubber, metal or plastic diaphragms which render the material permeable to gases. Yet another system, commonly called a positive displacement pump, or piston system, employs a mechanism which pushes a composition to the top of a container via a rising piston or pump. However, none of the aforementioned methods effectively eliminates headspace from a container. 
         [0005]    Generally, the aforementioned methods require manual expulsion of gases after filling, by way of a pump or compression of the container, which forces gases through a venting material. These methods are vulnerable to incomplete expulsion of gases and often result in backflow of gases into the container. Particularly, where gases are expelled by compression of a flexible container, when the container is allowed to return to its uncompressed position, some gas is likely to migrate back into the container. 
         [0006]    Therefore, a need still exists for a closure which creates zero-headspace during packaging, while preventing reintroduction of gas into the container. A need also exists to allow easy dispensing, from the same closure, of the contents of the package by a consumer. 
       SUMMARY OF THE INVENTION 
       [0007]    The present invention meets the aforementioned needs by providing a container suitable for containing a liquid composition and comprising an insert located in the neck of said container, and wherein when said container is filled with a liquid composition, zero headspace exists below said insert. 
         [0008]    While the invention will be described in connection with certain embodiments, it will be understood that the invention is not limited to these embodiments. On the contrary, the invention includes all alternatives, modifications, and equivalents as may be included within the spirit and scope of the present invention. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0009]    The accompanying drawings illustrate embodiments of the invention and, together with a general description of the invention given above, and the detailed description given below, serve to explain the invention. 
           [0010]      FIG. 1  is a side, elevational view of a container comprising a liquid composition and a insert described herein; 
           [0011]      FIG. 2  is an enlarged, perspective view of a valve employed as an insert in the container herein; 
           [0012]      FIG. 3  is top plan view of the valve shown in  FIG. 2 ; 
           [0013]      FIG. 4  is a side elevational view of the valve shown in  FIG. 2 ; 
           [0014]      FIG. 5  is an enlarged side view of a container comprising a liquid composition according to a dispensing assembly described herein; 
           [0015]      FIG. 6  is an enlarged side view of the upper portion of a container comprising a liquid composition and the insertion of a valve according to an embodiment of the invention; 
           [0016]      FIG. 7  is an enlarged side view of the upper portion of a container comprising a liquid composition which illustrates migration of a liquid composition through the valve upon insertion into the neck of a container. 
           [0017]      FIG. 8  is an enlarged side view of the upper portion of a container comprising a liquid composition, which illustrates substantial equilibrium on either side of a valve face, after insertion. 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0018]    While the specification concludes with claims that particularly point out and distinctly claim the invention, it is believed the present invention will be better understood from the following description. 
         [0019]    The term “insert” as used herein, refers to a mechanism which a liquid composition may pass through under conditions of a sufficient pressure differential and which may be fixed within a container suitable for liquid compositions. A valve is one type of insert. 
         [0020]    The term “valve” as used herein, means a device for halting or controlling the flow of a liquid, gas, or other material through a passage, pipe, inlet, outlet, etc., which is activated when a sufficient pressure differential is exerted upon it. 
         [0021]    The term “substantial equilibrium” as used herein, means that the force exerted on either side of a surface is nearly equal, or equal. Under conditions of substantial equilibrium, the valve herein remains sealed. The absence of a pressure differential results in substantial equilibrium. 
         [0022]    The term “pressure differential” as used herein, means the pressure exerted on one side of the insert herein, such that the insert is activated, and is thereby permeable. 
         [0023]    The term “zero headspace” as used herein, refers to the space between the bottom surface of the insert and the top surface of the liquid composition which is located below the insert, within the container. Upon achieving zero headspace, there is no space between the bottom surface of (below) the insert and the liquid composition. 
         [0024]    In one embodiment, the insert employed to achieve zero headspace is a valve  1 , which is designed to be effectively inserted into the neck  2  of a container  3 . The valve  1  is typically bonded or sealed to the inner wall  16  of the neck  2  by a retaining ring  5 . The valve  1  generally comprises a flexible, resilient material, which can open to dispense fluid under the exertion of a pressure differential, and which is substantially impermeable to liquids and gases in the relative absence of a pressure differential. The valve  1  may be fabricated from thermoplastic elastomers based upon materials such as thermoplastic propylene, ethylene, urethane, styrene, and their halogenated counterparts. Similar valves are described in U.S. Pat. No. 5,439,143 and U.S. Reissue Pat. No. RE39,520. Further valves are commercially available from suppliers such as Liquid Molding Systems, Inc. of Crystal lake, Ill. 
         [0025]    One type of valve  1 , as illustrated in  FIGS. 2-4 , includes a flexible central face  6  which has a concave configuration (when viewed from the exterior) and which defines two, mutually perpendicular, intersecting, dispensing slits  7  of about equal length. The intersecting slits  7  define four, generally sector-shaped, flaps  8  in the concave, central face  6 . The flaps  8  open outwardly from the intersection point of the slits  7 , in response to increasing container pressure of sufficient magnitude (pressure differential), which can be achieved by compressing a flexible container  3 , or upon insertion of the valve  1  into the neck  2  of the container  3  (described in detail hereinafter). 
         [0026]    The valve  1  includes a skirt  10  ( FIG. 4 ) which extends outwardly from the valve  1  central face  6 . At the outer (upper) end of the skirt  10 , there is a thin, annular flange  11  which extends peripherally from the skirt  10  in an angled orientation. The thin flange  11  terminates in an enlarged, much thicker, peripheral flange  12  which has a generally dovetail shaped transverse cross section. 
         [0027]    The lower surface of the peripheral flange  12  is bonded to a retaining ring  5 , which extends upwardly to form a cylinder  13 , which has a length which is typically slightly longer than the neck  2  of the container  3 . The cylinder  13  comprises an inner wall  14  and an outer wall  15 . The outer wall  15  of the cylinder  13  may comprise a matching means to seal the outer wall  15  of the cylinder  13  to a matching surface of the inner wall  16  of the neck  2  of the container  3 . The matching means may comprise threads, a clamping mechanism, a clipping mechanism, a bonding adhesive, or other means known in the art for creating a seal. 
         [0028]    As discussed above, when gases are present in packages which contain liquid compositions, the pocket of gas at the top of the package often disrupts composition, either chemically, aesthetically, or both. Although other gases may be present in the liquid composition as suspensions or gas capsules, the pocket of gas at the top of the package can migrate throughout the liquid composition during shipping, which causes the aforementioned disruptions. This problem is solved by a zero headspace insert. 
         [0029]    In one embodiment, zero headspace is achieved by filling the container  3  with a liquid composition  17  to a level  18  at or above the shoulders  19  of the container  3  as depicted in  FIG. 5 . Upon filling, the container typically has a volume of gas  9  (air) which remains at the upper portion of the container  3 , typically above the shoulders  19  and in the neck  2 . The valve  1  is inserted into the neck  2  to displace the liquid composition  17 . As the valve  1  descends into the neck  2 , the liquid composition  17  is displaced in the container  3 , until the valve  1  is forced to roll upwardly on itself and open, as depicted in  FIGS. 6 and 7 . The liquid composition  17  flows through the valve opening  4 , and accumulates above the valve  1 , generally in the neck  2  of the container  3 . The valve  1  then returns to its sealed position as depicted in  FIG. 8 , as the valve  1  reaches substantial equilibrium. After the valve  1  is inserted, and secured to the neck  2  via the matching means described hereinbefore, a cap (not depicted) may then be applied to the container  3  as a closure by various means which are known in the art. 
         [0030]    The zero headspace insert, described above, prevents gases, now above the valve  1 , from entering and disrupting the liquid composition  17  in the container  3 . This is particularly useful to prevent damage to liquid compositions which comprise patterns or designs, due to rotation of the container  3 , and migration of bubbles throughout the liquid composition  17 . Of course, preservation of such patterns and designs are particularly relevant to liquid compositions which are packaged in transparent containers. Therefore, in one embodiment, the container  3  is a transparent or semi-transparent container. 
         [0031]    In use, in order to expel the liquid composition  17  from the container  3 , the valve  1  must be removable, or the container  3  may be flexible. Accordingly, in one embodiment, the valve  1  is removable via a removable matching means, such as threads, as discussed hereinbefore. In the case of personal care compositions, or other less viscous liquid compositions, a compressible container may significantly improve ease of expulsion of a liquid composition. Therefore, in another embodiment, the container  3  is primarily made from a flexible plastic material such as polyethylene (PE), polypropylene (PP), or poly(ethylene terephthalate) (PET). Such materials may be fabricated as transparent, opaque, or semi-transparent containers. As discussed hereinbefore, compression of a flexible container  3  creates a pressure differential which is sufficient to expel the liquid composition  17  through the valve  1  without its removal. 
         [0032]    The dimensions and values disclosed herein are not to be understood as being strictly limited to the exact numerical values recited. Instead, unless otherwise specified, each such dimension is intended to mean both the recited value and a functionally equivalent range surrounding that value. For example, a dimension disclosed as “40 mm” is intended to mean “about 40 mm.” 
         [0033]    All documents cited in the Detailed Description of the Invention are, in relevant part, incorporated herein by reference; the citation of any document is not to be construed as an admission that it is prior art with respect to the present invention. To the extent that any meaning or definition of a term in this document conflicts with any meaning or definition of the same term in a document incorporated by reference, the meaning or definition assigned to that term in this document shall govern. 
         [0034]    While particular embodiments of the present invention have been illustrated and described, it would be obvious to those skilled in the art that various other changes and modifications can be made without departing from the spirit and scope of the invention. It is therefore intended to cover in the appended claims all such changes and modifications that are within the scope of this invention.