Abstract:
An improved piercing fitment assembly for mounting to a flexible container is provided, whereby the contents of the container are dispensed by piercing a pierceable portion of a cap using a fluid transfer device. The piercing fitment assembly is easy to use as a relatively minimal amount of force is required for piercing and establishing fluid transfer. It also has a locking system which locks the fluid transfer device into a dispensing state and also forms a reliable seal between the cap and the fluid transfer device which minimizes the risk of unwanted spillage. The fitment assembly comprises: a spout connected in fluid communication to the container; a cap having a pierceable portion sealing an end of the spout and a fluid transfer device having a leading tooth to initiate piercing of the pierceable portion of the cap.

Description:
RELATED APPLICATION 
     This application claims the benefit of U.S. Provisional Application No. 60/834,458, filed on Jul. 31, 2006, entitled “A Piercing Fitment Assembly”, with listed inventor, James W. Johnson. The entire teachings of the above application are incorporated herein by reference. 
    
    
     FIELD OF INVENTION 
     This invention relates to a piercing fitment assembly for use with flexible containers for flowable materials, such as liquids, and including aseptically-packaged flexible containers. 
     BACKGROUND OF THE INVENTION 
     Flexible polymeric containers are extensively used throughout the food service industry for storing and dispensing soft drink syrups and other such beverages, as well as wine, dairy products, enteral feeding solutions, fruit juices, tea and coffee concentrates, puddings, cheese sauces, and many other flowable materials, including those that must be filled aseptically. Flexible polymeric containers typically have walls made of polymeric films with either a monolayer or multiple layer structure. The particular polymers constituting the container film layers vary depending on the type of material to be placed in the container. The film layers may also include an oxygen barrier material layer to prevent contact between such materials and oxygen or other gas sensitive contents. The walls of the containers may be metallized, or coated with a metallic layer such as aluminum to prevent incursion of oxygen or other gases. 
     The flexible polymeric containers may have inlets and/or spouts for filling and dispensing the container contents. The containers are also often placed within a corrugated paper box. Such packaging systems are commonly referred to as “bag-in-box” systems wherein the spout extends through an opening in the box to dispense the contents. Bag-in-box packaging systems are often used in restaurants, institutional food service centres, and convenience stores to facilitate service of liquid food products such as syrups, toppings, condiments, beverages and dairy products. These containers typically have a capacity of 1 to 6 gallons. 
     Once the container is filled with a desired flowable material, the spout is capped to seal the container and protect the contents from contamination. Depending on the type of contents, the container, spout and cap may be sterilized using steam, hydrogen peroxide (H 2 O 2 ), radiation or other suitable sterilizing methods prior to, during and after filling. In order to maximize the shelf life of such products, it is crucial that fitment assemblies provide a hermetic seal for the entire life cycle of the container. 
     One convenient method of dispensing the contents of flexible containers is to open the containers by piercing the cap used to seal the container or by piercing the container directly using a fluid transfer device. Examples of dispensing systems that use piercing are disclosed in the following U.S. Pat. Nos. 4,325,496, 6,971,548 and 6,378,730. 
     Since flexible containers are typically intended for one-time use and are discarded once the contents of such containers have been completely dispensed, the fitment assembly must be made of inexpensive material, easy to manufacture, quick to market and preferably recyclable. It is also desirable that the fitment assembly for use with such packaging systems simplifies access to the container&#39;s contents while also minimizing the potential for contamination of the contents. Preferably, the contents of the flexible containers can also be easily dispensed without tools or the like. It is also desirable that the fitment assembly can be adapted to standard and widely-used spout configurations and can be easily adapted to a flexible hose or tube. The dispensing mechanism must be reliable such that dispensing of the contents is achieved without wasting the liquid through leakage or uncontrolled opening of the connection component and the like. 
     SUMMARY OF INVENTION 
     Accordingly, the present invention provides a fitment assembly which can be mounted to a flexible container, whereby contents of the container are dispensed by piercing a portion of the cap using a fluid transfer device. The piercing fitment assembly is easy to use as a relatively minimal amount of force is required for piercing and establishing fluid transfer. It also has a locking system which locks the fluid transfer device into a dispensing state and also forms a reliable seal between the cap and the fluid transfer device which minimizes the risk of unwanted spillage. 
     The piercing fitment assembly may be used, for example, with flexible containers that are filled or that are formed and filled using suitable commercial packaging systems known in the art. Such packaging systems may include vertical form film seal filling machines sold under the trade-marks PREPAC, IMPACO and ELECSTER, and, the Liqui-Box™ Filler Model 2000C1T-A that is used for filling flexible containers used in bag-in-box systems. The fitment assembly may also be used with flexible containers that are aseptically filled. 
     According to one broad aspect, the present invention provides a fluid transfer device for dispensing flowable material from a container by piercing. The fluid transfer device comprises a hollow body having: a longitudinal axis, a through internal passage, a piercing end and a dispensing end. The piercing end has a peripheral extremity that is tapered in relation to the longitudinal axis of the hollow body and the piercing end also has a leading tooth that is located at a distal extrema of the peripheral extremity to initiate piercing of a cap secured to a spout of a container. 
     In another embodiment of the invention, the leading tooth may comprise an exterior surface that is substantially parallel to the longitudinal axis of the hollow body and an interior surface that is inclined inwardly and forms an angle of 10° to 45° with the exterior surface. 
     Advantageously, the piercing end of the fluid transfer device may further comprise a plurality of additional teeth that are disposed around the peripheral extremity. The additional teeth facilitate piercing as they reduce the amount of force that is required for piercing a pierceable portion of the cap of the spout of the container and cause a circular membrane within the pierceable portion to be peeled back in order to establish fluid transfer. 
     According to another aspect, the present invention also provides a cap for securing to a spout of a container. The cap comprises a spout receiving side adapted for securing the cap to the spout of the container and a pierceable portion adapted to be pierced by a fluid transfer device. The pierceable portion of the cap comprises an indentation defining a circular membrane surrounded by a plurality of petaloid elements. Advantageously, the pierceable portion may be located within a central opening of the cap and a barrier may be used to cover the central opening and hence the pierceable portion so as to keep the pierceable portion in a substantially sterile state prior to dispensing. 
     According to a further aspect, the present invention also provides a fitment assembly for a container. The fitment assembly comprises: a spout connected in fluid communication to the container; a cap sealing a dispensing end of the spout, the cap having a pierceable portion; and a fluid transfer device including a piercing end and a dispensing end. The fluid transfer device has a longitudinal axis and a through internal passage and is used for piercing the cap at the pierceable portion to permit fluid communication from the container through the spout and the fluid transfer device. The piercing end of the fluid transfer device includes a leading tooth to initiate piercing of the pierceable portion of the cap. 
     The piercing end of the fluid transfer device may have a peripheral extremity that is tapered in relation to the longitudinal axis of the fluid transfer device wherein the leading tooth is located at a distal extrema of the tapered peripheral extremity so as to initiate piercing of the pierceable portion of the cap during piercing. Advantageously, the piercing end may further comprise additional teeth disposed around the peripheral extremity of the piercing end so as to subsequently and progressively puncture the pierceable portion of the cap during piercing. 
     Preferably, the pierceable portion of the cap also comprises an indentation defining a circular membrane surrounded by a plurality of petaloid elements. Advantageously, the pierceable portion is further adapted to cooperate with the fluid transfer device such that the circular membrane remains attached to the cap by a hinge-like connection that is formed during piercing. 
     The fitment assembly may further comprise a locking mechanism adapted to secure the fluid transfer device to the cap as a result of a pushing force exerted on the fluid transfer device in an essentially axial direction within the spout, whereby the piercing end is in piercing engagement with the cap. The locking mechanism may comprise an annular recessed portion on the piercing end of the fluid transfer device adapted to cooperate with the petaloid elements of the pierceable portion of the cap so as to prevent removal of the fluid transfer device from the cap once the piercing fitment assembly is in a dispensing state and thereby prevent unwanted spillage. 
     According to another aspect, the present invention also provides a pierceable port for a flexible container comprising: a pierceable portion adapted to be pierced by a fluid transfer device. The pierceable portion comprises an indentation defining a circular membrane surrounded by a plurality of petaloid elements. The pierceable port can be secured to the flexible container. The pierceable port may further comprise a skirt extending outwardly from a container side of the pierceable port and surrounding the pierceable portion. The skirt serves as a spacer to keep any portion of any adjacent container wall away from the pierceable portion thereby preventing the container walls from being pierced by the fluid transfer device. 
     According to a further aspect, the present invention also provides a flexible container comprising the pierceable port described above. The pierceable port may be secured to the flexible container by a flange secured to a wall surface of the flexible container. The pierceable port may also be secured to the flexible container so that the pierceable portion is aligned with an opening in the flexible container. Alternatively, if the pierceable portion is not aligned with an opening in the flexible container and the flange is secured to an outside wall surface of the container, a portion of the pierceable portion may also be secured to the outside wall surface. This prevents excessive stretching of the container material in the area of the pierceable portion during piercing and allows the container to be pierced more easily by the fluid transfer device. 
     According to yet another aspect, the present invention also provides a fitment assembly for a container comprising a pierceable port and a fluid transfer device. The pierceable port is secured to a wall of the container and includes a pierceable portion. The port may include a flange by which it may be secured to the container. The fluid transfer device comprises a through internal passage, to permit fluid communication from the container through the fluid transfer device. The fluid transfer device may be of the type previously described. 
    
    
     
       BRIEF DESCRIPTION OF THE FIGURES 
         FIG. 1  shows a cross-sectional side elevation view of a piercing fitment assembly, in a disassembled state, according to one embodiment of the invention. 
         FIG. 2  shows a perspective view of the fluid transfer device of the piercing fitment assembly of  FIG. 1 . 
         FIG. 3  shows a cross-sectional side elevation view of a piercing end of the fluid transfer device of the piercing fitment assembly of  FIG. 1 . 
         FIG. 4  shows a top plan view of the cap of the piercing fitment assembly of  FIG. 1  without a barrier. 
         FIG. 5  shows a cross-sectional side elevation view of the piercing fitment assembly of  FIG. 1  in a ready-to-pierce state. 
         FIG. 6  shows a cross-sectional side elevation view of the piercing fitment assembly of  FIG. 1  in a dispensing state. 
         FIG. 7  shows a top plan view of a cap of a piercing fitment assembly according to another embodiment. 
         FIG. 8  shows a side elevation view of a fluid transfer device of a piercing fitment assembly according to another embodiment. 
         FIG. 9  shows a perspective view of a fluid transfer device according to another embodiment of the invention. 
         FIG. 10  shows a perspective view of a fluid transfer device according to another embodiment of the invention. 
         FIG. 11  shows a cross-sectional perspective view of a piercing fitment assembly, in a disassembled state, according to a another embodiment of the invention. 
         FIG. 12A  shows a cross-sectional side elevation view of a piercing fitment assembly according to another embodiment of the invention. 
         FIG. 12B  shows a cross-sectional side elevation view of the piercing fitment assembly of  FIG. 12A  in a dispensing state. 
         FIG. 13A  shows a cross-sectional side elevation view of a piercing fitment assembly according to another embodiment of the invention. 
         FIG. 13B  shows a cross-sectional side elevation view of the piercing fitment assembly of  FIG. 13A  in a dispensing state. 
         FIG. 14A  shows a cross-sectional side elevation view of a piercing fitment assembly according to another embodiment of the invention. 
         FIG. 14B  shows a cross-sectional side elevation view of the piercing fitment assembly of  FIG. 14A  in a dispensing state. 
         FIG. 15A  shows a cross-sectional side elevation view of a piercing fitment assembly according to another embodiment of the invention. 
         FIG. 15B  shows a cross-sectional side elevation view of the piercing fitment assembly of  FIG. 15A  in a dispensing state. 
         FIG. 16A  shows a cross-sectional side elevation view of a piercing fitment assembly according to another embodiment of the invention. 
         FIG. 16B  shows a cross-sectional side elevation view of the piercing fitment assembly of  FIG. 16A  in a dispensing state. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     Referring particularly to the drawings, the figures are for the purpose of illustrating the present invention only and not for the purpose of limiting the scope of the appended claims. 
     Referring now to  FIG. 1 , there is illustrated a piercing fitment assembly shown generally at  1  according to the invention for use with flexible containers for flowable materials, such as liquids, and particularly for aseptically-packaged flexible containers. The piercing fitment assembly  1  comprises a spout shown generally at  10  mounted to a flexible container  2 , a cap shown generally at  20  and a fluid transfer device shown generally at  40 . 
     The configuration of the spout  10  shown in  FIG. 1  is widely-used, commercially available and is conventionally adapted for mounting to flexible containers such as bag-in-box containers, namely bags. However, it is understood that the piercing fitment assembly of the present invention could easily be modified to comprise other configurations of spouts. The spout  10  has a generally cylindrical shape and has a through central opening  14 . The central opening  14  of the spout  10  is in communication with the container  2  (a top portion of which is shown) via an opening  3  in the container  2 . At its base, the spout  10  also has a relatively thin outwardly projecting flange  11  that is used to secure the spout  10  to an inside wall surface  4  of the container  2 . The top surface  12  of the flange  11  is bonded to form a hermetically sealed connection with the inside wall surface  4  of the container  2  by known means such as heat sealing, adhesive or the like. 
     The cap  20  has a generally cylindrical shape but could be made to adapt other shapes of spouts such as oval or polygon-shaped. The cap  20  has a central opening  22  which has an interior circumferential surface  30 . The cap  20  also has, within the central opening  22 , a pierceable portion  31  which has an indentation which comprises a circular portion  33  and several radial portions  34  as shown in  FIG. 4 . The indentation formed by portions  33  and  34  is an area of reduced material thickness within the pierceable portion  31  which defines a circular membrane  27  surrounded by a plurality of petaloid elements  29  within the pierceable portion  31 . The cap  20  also has an annular opening  26  which is adapted for receiving the spout  10  and hermetically securing the cap  20  to the spout  10 . Located inside the annular opening  26  is an inside surface  25  and an annular bead  24 . The cap  20  may further comprise a barrier  21  secured to a top surface  23  of the cap  20  for sealing the central opening  22 . 
     The fluid transfer device  40  also has a generally cylindrical shape and comprises, a dispensing end shown generally at  41 , a piercing end shown generally at  42 , a through internal passage  43  and a handle  44  between the dispensing end  41  and the piercing end  42 . The handle  44  comprises an outwardly projecting flange and has a bottom surface  45 . The dispensing end  41  has a ribbed exterior portion  51  which is adapted to be secured to a dispensing tube (not shown). The piercing end  42  has an exterior cylindrical surface  52  and an annular recessed portion  50  which is part of a snap-fitting locking mechanism. The piercing end  42  also comprises a guiding surface  49  which has an inwardly extending conical profile which leads to a peripheral extremity  46  that is tapered in relation to a longitudinal axis of the fluid transfer device  40 . 
     The fluid transfer device  40  further comprises at a minimum, a leading tooth  47  located at a distal extrema  53  of the tapered peripheral extremity  46  and in a preferred embodiment, includes a plurality of additional teeth  48  which are disposed around the peripheral extremity  46  of the piercing end  42 . The configuration of the teeth ( 47  and  48 ) is shown in details in  FIGS. 2 and 3 . The leading tooth  47  comprises an exterior surface  56  which is relatively parallel to the longitudinal axis of the fluid transfer device  40  and an interior surface  55  which is inwardly inclined and forms an angle of 10° to 45° with the exterior surface  56 . The additional teeth  48  may have the same or different geometric features as the leading tooth  47 . The leading tooth  47  and the additional teeth  48  may comprise a total number of teeth of 3, 5, 7, etc.  FIG. 9  shows a fluid transfer device having 3 teeth and  FIG. 10  shows a fluid transfer device having 5 teeth. 
     Filling of flexible containers such as the ones used in bag-in-box systems may be performed on any suitable aseptic filler known to those skilled in the art, and is typically performed using commercial packaging systems such as, for example, the Liqui-Box™ Filler Model 2000C1T-A (not shown). Before filling and aseptic packaging, the container  2  is supplied to the packaging system in a state where the inside of the container has been pre-sterilized using Cobalt gamma irradiation or any other suitable means of sterilization. The spout  10 , cap  20  and fluid transfer device  40  are also sterilized using Hydrogen Peroxide (H 2 O 2 ), steam or any other suitable means. Once the container  2  has been filled via the spout  10  with flowable material, the cap  20 , comprising a barrier  21  hermetically bonded to the top surface  23 , is secured to the spout  10 . The fluid transfer device  40  is provided to the customer together with the filled and capped container in a separate sterilized plastic bag (not shown) which is only opened when the contents of the container  2  are to be dispensed. 
       FIG. 5  shows the cap  20  installed on the spout  10  of the flexible container  2 . The cap  20  is installed in a snap-fitting manner by firstly positioning the cap  20  and the spout  10  such that the spout-receiving annular opening  26  receives the end of the spout  10 . An inward axial force is applied to the cap  20  such as to press the cap  20  against the spout  10 . The annular bead  15  forcefully and resiliently slides against the inside surface  25  and forms a substantially hermetic seal between the cap  20  and the spout  10 . Once the cap  20  is installed on the spout  10 , the annular bead  24  on the cap  20  cooperates with the outwardly projecting flange  13  on the spout  10  such as to lock the cap  20  into position. 
     The barrier  21  maintains the central opening  22  and the pierceable portion  31  of the cap  20  in a substantially sterile state during shipping and storage of the container. Preferably, the barrier  21  may be substantially gas or oxygen impermeable and may include any suitable material such as foil, ethylene vinyl alcohol, polyvinyl alcohol, polyethylene or a metalized polyester laminate. The barrier  21  may be attached to the top surface  23  of the sterilized cap  20  by heat sealing, ultrasonic welding or other known methods. The barrier  21  may be removed prior to piercing the pierceable portion  31  of the cap  20  or it may be left on the cap  20  and pierced using the fluid transfer device  40 . 
     The container  2  would usually be placed in a dispensing position wherein the fitment assembly  1  extends outwardly or downwardly from the container so as to allow gravity to aid in dispensing of the contents. The contents of the container  2  are dispensed by firstly removing the barrier  21  from the cap  20 . The fluid transfer device  40  is then removed from the sterilized plastic bag (not shown) and the dispensing end  41  may be connected to a dispensing tube (not shown) or other fluid delivery systems. The piercing end  42  of the fluid transfer device  40  is inserted into the central opening  22  and pressed axially inwardly towards the cap  20 , using the handle  44 , such as to pierce the pierceable portion  31 .  FIG. 5  shows the fluid transfer device  40  positioned within the central opening  22  of the cap  20  in a position ready to pierce the pierceable portion  31  of the cap  20 .  FIG. 6  shows the fluid transfer device  40  in a dispensing position within the cap  20  wherein the pierceable portion  31  has been fully pierced. Alternatively, depending on the type of material used for the barrier  21 , the barrier  21  may be left in place and pierced using the fluid transfer device  40  before piercing the pierceable portion  31  of the cap  20 . 
     The leading tooth  47  and the additional teeth  48  permit a relatively effortless piercing of the pierceable portion  31  by concentrating the force at distinct points on the pierceable portion  31  and hence facilitating the piercing process. The leading tooth  47  firstly punctures the circular portion  33  of the indentation and as the piercing end  42  of the fluid transfer device  40  is further inserted, the additional teeth  48  subsequently come in contact with and puncture the circular portion  33  in a progressive manner so as to leave the circular membrane  27  hingedly attached to the cap  20 . The additional teeth  48  need not have the same geometric configuration as the leading tooth  47 . In the present embodiment, the leading tooth  47  and the additional teeth  48  are shown to have a generally pyramidal geometry, however, any other suitable geometric configurations which minimize the force required to pierce the pierceable portion may be used. 
     As the leading tooth  47  punctures the circular portion  33  of the indentation, it proceeds in tearing the circular portion  33  as the interior surface  55  presses downwardly and radially inwardly on the circular membrane  27  so as to peel back the circular membrane  27  from the pierceable portion  31 . As the guiding surface  49  proceeds to enter the pierceable portion  31 , the petaloid elements  29  are pushed and deflected downwardly and thereby cause the material within the radial portions  34  of the indentation to become stretched. Consequently, this creates a tight fit between the piercing end  42  and the pierceable portion  31  of the cap  20  and thereby prevents unwanted leakage. In  FIG. 4 , the petaloid elements  29  are shown to have a generally square profile but a more rounded profile as shown in  FIG. 7  can also be used. 
     Once the fluid transfer device  40  is fully inserted, the bottom surface  45  of the handle  44  comes in contact with the top surface  23  of the cap  20  and the fluid transfer device  40  becomes locked into a dispensing position within the cap  20  via a snap-fitting mechanism. The petaloid elements  29  and the stretched radial portions  34  of the indentation become engaged with the annular recessed portion  50  of the fluid transfer device  40  as shown in  FIG. 6 . This prevents the fluid transfer device  40  from being pulled out from the cap  20  once the piercing fitment assembly  1  is in a dispensing state and also maintains a tight fit between the cap  20  and the fluid transfer device  40  to prevent unwanted spillage. 
       FIG. 6  clearly shows how the circular membrane  27  remains connected to the cap  20  via a hinge  32 . Through the cooperation of the piercing end  42  of the fluid transfer device  40  and the pierceable portion  31  of the cap  20 , the hinge  32  is automatically formed upon piercing and comprises a portion of the pierceable portion  31  which remains unbroken once the fluid transfer device  40  has been fully inserted and locked into the dispensing position. The circular membrane  27  is thereby prevented from becoming loose and potentially obstructing the flow or being dispensed together with the contents. 
     The location of the hinge  32  within the pierceable portion  31  is dependent on the orientation of the fluid transfer device  40  when piercing occurs as the hinge  32  is automatically formed at a location adjacent to a proximal extrema  54  of the peripheral extremity  46 . Therefore, the piercing end  42  of the fluid transfer device  40  does not have to be inserted into the cap  20  in any particular orientation for the hinge  32  to be formed. 
     The ribbed exterior portion  51  of the dispensing end  41  shown in the preferred embodiment is adapted to receive a dispensing tube (not shown). Obviously, other types of adapters could also be used for connecting the fluid transfer device  40  to a delivery system. The dispensing end  41  could also be in fluid communication with a dispensing tap which could be used to regulate the flow of flowable material. In another embodiment, the dispensing end  41  may also comprise a dispensing tap  57  as shown in  FIG. 8  that is integral to the fluid transfer device  40 . 
       FIG. 11  shows a piercing fitment assembly according to another embodiment that is mainly used for dairy applications. The cap  20  in this case has a slightly different geometric configuration but still comprises the pierceable portion  31  adapted to be pierced by the fluid transfer device  40 . 
     In yet another embodiment, the present invention also provides a piercing fitment assembly wherein a pierceable port is secured directly to a wall of a flexible container. Examples of such pierceable ports are shown generally at  80  in  FIGS. 12A to 16B . This type of pierceable port can be used, for example, on containers that are filled on vertical form film seal filling machines where no spout is needed for filling the containers. The pierceable port  80  comprises a flange  81  that is adapted for securing the pierceable port  80  to an outside wall surface  5  (shown in  FIGS. 12A to 15B ) or an inside wall surface  4  (shown in  FIGS. 16A and 16B ) of the container  2 . The pierceable port also comprises an exterior side generally shown at  83 , a container side generally shown at  84 , and, a pierceable portion  31  that is adapted to be pierced by the fluid transfer device  40  as previously described. Similarly, the pierceable port may also comprise the barrier  21  secured to the exterior side  83  in order to keep the pierceable portion  31  in a substantially sterile state prior to dispensing the contents of the container  2 . 
       FIGS. 14A and 14B  show the pierceable port  80  according to another embodiment which comprises a skirt  82 . The skirt extends outwardly from a container side  84  of the pierceable port  80  and surrounds the pierceable portion  31 . The skirt  82  serves as a spacer or guard to keep any portion of any adjacent container wall away from the pierceable portion  31  thereby preventing the container  2  from being pierced by the fluid transfer device  40 . 
       FIGS. 13A ,  13 B,  14 A,  14 B,  16 A and  16 B show embodiments of pierceable ports  80  that are secured to the container  2  either on an outside wall surface  5  or an inside wall surface  4  at a location where the pierceable portion  31  is aligned with an opening  3  in the container  2 . However, as shown in  FIGS. 12A ,  12 B,  15 A and  15 B, the pierceable portion does not have to be aligned with an opening  3  in the container  2  if the flange  81  is secured to the outside wall surface  5 . In such a case, it is preferable that at least a portion of the pierceable portion  31  also be secured to the outside wall surface  5 . This prevents excessive stretching of the container material in the area of the pierceable portion during piercing and allows the container  2  to be pierced more easily by the fluid transfer device  40 . 
     Since these containers are typically intended for one-time use and are discarded once the contents of such containers have been completely dispensed, it is preferable that the fitment assembly for use in such systems be easy to manufacture, inexpensive, easy to install and use, and recyclable. It is also important that the components are of sufficient quality and robustness. Accordingly, the construction of the components required to produce the piercing fitment assembly of the present invention is relatively simple and economical. The spout  10 , cap  20 , pierceable port  80  and fluid transfer device  40  can all be produced from commonly used and recyclable thermoplastic materials and formed using conventional plastic injection molding processes. For example, the cap  20  and pierceable port  80  may preferably be made using a blend of 85% medium density linear low density polyethylene (LDPE) and 15% high density polyethylene (HDPE). The fluid transfer device  40  may be produced using high density polyethylene (HDPE) or polypropylene (PP). Alternatively, the fluid transfer device  40  may be made using a commercially available low density polyethylene. It was found that the use of a softer low density polyethylene for the fluid transfer device  40  in comparison with HDPE causes the force required to pierce the cap  20  or pierceable port  80  to be reduced. It is believed that the use of a softer material for the fluid transfer device  40  allows the piercing end  42  of the fluid transfer device  40  to be more accommodating to a rupture path, in the piercing portion  31 , that offers less resistance during piercing. The reduction in piercing force was more notable on caps  20  and pierceable ports  80  having a pierceable portion  31  of comparatively smaller diameter. 
     Thinner regions of injection molded parts typically impose challenges with respect to suitable mold and process design for injection molding. Accordingly, the thinner circular potion  33  and radial portions  34  of the pierceable portions  31 , may be formed using a separate punch (not shown) used to score or indent the cap  20  or pierceable port  80  once it has been molded with thicker dimensions. The punch can preferably be integrated within the mold wherein the forming of the thinner regions may take place prior to or as the part is ejected from the mold. The specific configuration of such a mold with integrated punch would be apparent to one skilled in the art. 
     From the foregoing description, it can be seen that the present invention comprises a piercing fitment assembly which is used with flexible containers. It will be appreciated by those skilled in the art that obvious changes can be made to the embodiments described in the foregoing description without departing from the broad inventive concept thereof. It is understood, therefore, that this invention is not limited to the particular embodiments disclosed, but is intended to cover all obvious modifications thereof which are within the scope and the spirit of the invention as defined by the appended claims.