Patent Application
20060163191
The present invention relates generally to container closures and the construction of closure liners that are intended to provide sealing at an interface between the closure and the corresponding container. Without a sealing liner, there is a greater risk that the contents within the container will leak past the point of connection between the closure and the container and/or will allow oxygen ingress into the container.
More specifically, the present invention relates to the construction and arrangement of a liner that is suitable for a hot fill process, an aseptic fill process, and/or a nitrogen fill process. Each of these three processes affect the container/closure structure in slightly different ways, and this in turn requires a slightly different sealing strategy and sealing design for the closure liner and its interfit between the closure and the container.
Regardless of the fill process selected for a particular container/closure combination, the sealing liner of the present invention is suitable for creating and maintaining sealing at the interface(s) between the container and the closure. In order to provide this design versatility, the sealing liner of the present invention has an annular wave portion adjacent an outer peripheral edge of the sealing liner. This wave portion includes two axially protruding, concentric ridges that define therebetween an annular concave portion that is constructed and arranged to position itself against an upper surface of the container neck finish. This specific liner construction is novel and unobvious and provides an improvement to current liner designs in terms of versatility and the integrity of the seal.
A container, closure, and liner combination according to one embodiment of the present invention comprises a container having a neck finish, a unitary closure having a sidewall and an upper panel, and a sealing liner received by the closure for sealing a container/closure interface. The unitary closure is constructed and arranged for attaching to the neck finish. The sealing liner includes a unitary body having a substantially circular shape with an outer peripheral edge, an inner panel, and an annular wave portion surrounding the inner panel and being positioned between the inner panel and the peripheral edge. The wave portion being constructed and arranged with an inwardly directed surface that includes two axially-projecting, concentric annular portions, and a concave land area between the two portions. The land area is designed to contact an upper edge of the container neck finish with one annular portion on the outer surface of the neck finish and another annular portion on an inner surface of the neck finish.
One object of the present invention is to provide an improved container, closure, and liner combination.
Related objects and advantages of the present invention will be apparent from the following description.
For the purposes of promoting an understanding of the principles of the invention, reference will now be made to the embodiments illustrated in the drawings and specific language will be used to describe the same. It will nevertheless be understood that no limitation of the scope of the invention is thereby intended, such alterations and further modifications in the illustrated device, and such further applications of the principles of the invention as illustrated therein being contemplated as would normally occur to one skilled in the art to which the invention relates.
Referring to
As the assembly 20 is threaded onto the neck finish 29, the liner 21 is drawn into contact with top edge 31. The construction and arrangement of liner 21 is such that, with suitable threaded engagement and threaded tightening of the assembly 20 onto the neck finish 29, a sealed interface is established by liner 21 between the closure 24 and the top edge 31 of the container neck finish 29.
As mentioned in the Background, the container 30 and the closure 24 are intended to represent something of a generic design wherein the combination may be subjected to a hot fill process or to an aseptic fill process or to a nitrogen fill process. As used herein in the context of the present invention, a hot fill process is just what its name implies. The product being placed in the container is hot at the time of filling. During this process, the neck finish 29 of the container 30 shrinks inwardly away from the edge of the internal threads on closure 24. This result is expected due to the properties of PET material that is used for the container. As the product in the container cools as part of the overall cooling process, a vacuum is created as the contents go from hot to cold. Due to the positional and dimensional shifts between container 30 and closure 24, the selected liner, such as liner 21, needs to provide a secure and continuous seal between the container 30 and closure 24. In order to provide the requisite secure and continuous seal at the container edge and closure interface, the focus of the design for liner 21 is on its wave portion that is positioned between the interior panel and the outer peripheral edge and the ability of this wave portion to contact and seal against the top edge 31 of the neck finish. As described, the wave portion includes an annular concave portion that is constructed and arranged and positioned so as to fit down over top edge 31 in order to establish and maintain a secure and continuous seal between the container 30 and closure 24. The construction and functioning of liner 21 for the hot fill process are explained in greater detail hereinafter.
In the aseptic fill process, as defined for purposes of the present invention, a container is filled with product at or near room temperature in a sterile environment. It is intended to maintain the sterile condition of the product and it is important to do so in view of the particular product selected for the container. Accordingly, the construction and arrangement of the selected liner, such as liner 21, is an important aspect of being able to maintain the requisite sterile condition for the contents placed in the container. The construction and functioning of liner 21 for the aseptic fill process are explained in greater detail hereinafter.
In the nitrogen fill process, as defined for the purposes of the present invention, a small amount of very cold nitrogen is placed in the container. As the temperature of the nitrogen approaches the ambient temperature (i.e., warms up), pressure is created in the head space between the container contents and the closure. Due to this internal pressure, it is important for the selected liner, such as liner 21, to be able to provide a secure and suitable seal at the interface between the container 30 and closure 24. The construction and functioning of liner 21 for the nitrogen fill process are explained in greater detail hereinafter.
Referring again to
With reference to
By the design, construction, and positioning of ridges 37, including the inclined upper surface of each ridge in proximity to its corresponding wing 35, even if a small implement or tool is inserted to try and pull down the wings, the wing will abut up against each corresponding ridge 37 before the wing 35 can be positioned so as to clear the A diameter stop 36.
The use of ridges 37 as either a segmented plurality (see
The upper panel 23 of closure 24 connects to the generally cylindrical sidewall 28 at circular “corner” 41. The upper surface 42 of panel 23 is substantially flat as is the center portion 43 of inner surface 22. Positioned between center portion 43 and corner 41 is an annular, axially-protruding ridge 44 that includes two axially-projecting, concentric annular portions 45 and 46 (see
With reference to
The downward or inwardly-directed surface 51b of wave portion 51 includes two axially-projecting, concentric annular portions 61 and 62. Each portion 61 and 62 is generally V-shaped with a rounded tip 61a and 62a, respectively. An annular concave land area 63 is defined by and between projecting portions 61 and 62. Land area 63 is rounded at its base 63a.
Liner 21 is of a substantially uniform thickness, both prior to forming or shaping of the wave portion 51 and after the forming or shaping of wave portion 51. Further, the various contours and shaping of the upper surface 51a each have a reverse aligned contour or shaping in the lower surface 51b. For example, each annular channel 56 and 57 has a corresponding projecting portion 61 and 62, respectively. A similar correspondence exists between ridge 58 in the upper surface 51a and land area 63 in lower surface 51b. In effect, the forming of the channels on one side of the liner 21 creates the projecting portions or vice versa. Additionally, the shaping of the upper surface 51a of wave portion 51 of liner 21 corresponds to the shaping of ridge 44 in inner surface 22. In this way, the liner 21 has an overall close conforming shape as it fits up against the inner surface 22. With reference against to
With reference to
As previously described, the closure and liner assembly 20 is constructed and arranged to provide a suitable sealed interface with container 30, whether the container is subjected to a hot fill process, an aseptic fill process, or a nitrogen fill process. More specifically, during the hot fill process, a vacuum is created. Since the liner 21 has both inside and outside contact by the pressure of projecting portions 45 and 46, as well as axial compression of top edge 31 into concave land area 63, a secure seal is established and maintained for the closed container 30.
For the aseptic fill process, it is important to maintain the closed container, i.e., the container contents, sterile. Since liner 21 has both inside and outside contact by the pressure of projecting portions 45 and 46, as well as axial compression of top edge 31 into concave land area 63, a secure seal is established and maintained for the closed container 30.
For the nitrogen fill process, an internal pressure is created in the head space between the liner 21 and container contents. Since the liner 31 has both inside and outside contact by the pressure of projecting portions 45 and 46, as well as axial compression of top edge 31 into concave land area 63, a secure seal is established and maintained for the closed container 30. Regardless of the fill process that is selected for the container and closure combination 20, liner 21 provides, in cooperation with closure 24, an effective and reliable seal for the interface between the container and the closure.
The wave seal liner 21 can be produced from any of the common EVA-based copolymer liner materials that are commercially available. So long as the closure configuration is maintained, the liner 21 can be used in combination with either a metal or a plastic closure. The present invention and the design of liner 21 takes into account the option for adding a barrier to protect the contents from oxygen ingress. In this regard, it is anticipated that the liner can be compounded with an oxygen scavenger material or with clay platelets.
While the invention has been illustrated and described in detail in the drawings and foregoing description, the same is to be considered as illustrative and not restrictive in character, it being understood that only the preferred embodiment has been shown and described and that all changes and modifications that come within the spirit of the invention are desired to be protected.
