Patent Publication Number: US-2007101751-A1

Title: Freezer pop containing at least one active agent

Description:
This application claims the benefit under 35 U.S.C. § 120 of the earlier filing date of U.S. patent application Ser. No. 10/868,102, filed Jun. 15, 2004, which application is hereby incorporated by reference in its entirety.  
      The present invention relates to packaging for active agent-containing freezer pops, and more particularly to a moisture barrier-containing packaging for freezer pops containing an active agent which needs protection against moisture loss, such as a pharmaceutical, which substantially reduces or eliminates moisture loss in the packaged product.  
     BACKGROUND OF THE INVENTION  
      Frozen ice products including “snowballs”, Italian ices, freezer pops and frozen fruit juices have long been popular treats among consumers especially during the warmer weather months. Frozen ice products of this type can be carried on sticks, in plastic tubes, or in wax coated paper containers. No utensils or plates are necessary. One popular frozen ice product in particular is the freezer pop, which has been a staple of summer treats form any years. The freezer pop can be purchased and consumed in either as a chilled liquid or as a frozen product. The freezer pop is simple and convenient to store and distribute, and less messy to consume than other kinds of frozen ice products.  
      The conventional freezer pop is generally packaged in a substantially tubular pouch formed from two plastic laminate films adhesively joined and sealed along the common edges thereof. The sealed plastic laminate films, in combination, define a central cavity for enclosing a freezable liquid. The freezable liquid typically contains a flavoring agent, a coloring agent and/or a sweetener. Freezer pop formulations are described in published European Patent Application EP 1 287 747 A2 published Mar. 5, 2003, incorporated herein by reference. To form the freezer pop, a freezable liquid is cooled to temperatures sufficiently low to freeze the liquid as the freezer pop takes the shape of the central cavity. Thereafter, the freezer pop can be dispensed from the packaging by first cutting off the top end of the pouch to form an opening. The consumer simply presses the bottom end of the pouch to slide the freezer pop out through the opening. Alternatively, the freezer pop can be consumed in the liquid form by simply drawing the freezable liquid through the opening in the packaging.  
      Since freezer pops are seasonal products and are usually kept in the freezer or on the shelves for relatively short periods of time at a time, extended shelf life is not required for such products. Typically, the packaging film used for conventional freezer pops is fairly pervious to moisture, which can result in significant moisture loss over an extended period of time. The amount of moisture loss can reach 20% to 30% or more. As indicated above, due to their seasonal nature, conventional freezer pops are not adversely affected by long-term moisture loss. Therefore, the packaging used in freezer pops is generally designed for storage over a relatively short period of time.  
      Recently, active agents including, pharmaceuticals, medicaments and nutritional agents and the like have been added to freezer pop formulations to provide a unique vehicle for dosing various active agents to patients including children. However, the packaging used to house freezer pops containing such active agents has been found to be inadequate. This is because conventional packaging allows excessive moisture loss over an extended period of time, and current laws regulating typical active agents such as pharmaceuticals generally require a shelf life of two years. The amount of moisture loss typically encountered in current packaging is considered unacceptable for freezer pops which contain controlled amounts and concentrations of active agents. Such moisture loss can adversely affect the taste, ingredient balance, consistency, quality perception, and efficacy of the product.  
      Accordingly, it would be desirable to develop a packaging for storing a freezable liquid containing an active agent, which greatly enhances the shelf life and quality of the product. It would be further desirable to develop a packaging for freezer pops, which significantly reduces or eliminates undesirable moisture loss that would otherwise adversely affect the taste, quality, ingredient balance, and efficacy of the product.  
     SUMMARY OF THE INVENTION  
      The present invention relates generally to packaging for storing a freezable liquid containing an active agent so that the active agent may be administered through a freezer pop. The packaging of the present invention includes an arrangement of film layers including a moisture barrier, which substantially reduces or eliminates undesirable moisture loss, thereby enhancing the quality and storage life of the freezable liquid. In addition, the packaging of the present invention is designed to resist tears and punctures for enhanced child-proof safety.  
      In one aspect of the present invention, there is provided a packaging in the form of a freezer pop for storing a freezable liquid, the packaging comprising:  
      a sealed chamber for storing the freezable liquid formed from at least one inner layer having a sealable edge portion comprised of a sealable material and sealed at the edge portion;  
      at least one outer layer comprised of a tear and puncture resistant material having an outside surface;  
      at least one intermediate layer which is in sealable contact with both the at least one inner and outer layers, such that all layers are sealable together to form the sealed chamber; and  
      at least one moisture barrier layer in proximity to the outer layer for at least substantially preventing moisture from escaping the sealed chamber for an extended period of time.  
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
      The following drawings in which like reference characters indicate like parts are illustrative of embodiments of the invention and are not intended to limit the invention as encompassed by the claims forming part of the application.  
       FIG. 1  is a perspective view of a packaging containing a freezable liquid in one embodiment of the of the present invention;  
       FIG. 2  is an enlarged cross sectional view of the packaging along lines  2 - 2  of  FIG. 1  in accordance with the present invention; and  
       FIG. 3  is a schematic cross-sectional view of a packaging illustrating the layers used to form the sealed chamber in accordance with one embodiment of the present invention. 
    
    
     DETAILED DESCRIPTION OF THE INVENTION  
      As used herein, the term “freezer pop” refers to a consumable freezable liquid contained within a sealed chamber which may be opened by the consumer to ingest the freezable liquid when in liquid or frozen form. The size and shape of the sealed chamber may vary and is only limited by the practicality of producing a consumer product.  
      The term “active agent” refers to any one or more ingredients which may be incorporated into a freezer pop to provide a beneficial effect to the consumer upon ingesting the freezer pop. The active agent will typically be a therapeutic agent such as pharmaceuticals, medicaments, nutritional agents, vitamins, neutraceuticals and the like.  
      The present invention is directed generally to packaging for a freezer pop containing one or more active agents as defined herein. The packaging containing the freezer pop, can be placed in a freezer to freeze the liquid. The packaging of the present invention is also designed to provide sufficient tear and puncture resistance to provide adequate child safety features, while withstanding the effects normally encountered with freezing and thawing the freezable liquid. Furthermore, the packaging of the present invention includes a moisture barrier that significantly reduces or eliminates moisture loss from the freezable liquid, which would otherwise adversely affect the quality and storage life of the freezer pop and the active agent that may be contained therein. Accordingly, the packaging of the present invention provides excellent protection against moisture loss, thereby maintaining the taste, quality, ingredient balance and efficacy of the freezable liquid and particularly any active agents contained therein.  
      Referring to the drawings and first to  FIG. 1 , there is shown a packaging designed for enclosing a freezable liquid in the form of a freezer pop which may contain an active agent. The packaging identified generally by reference numeral  10  is shown having a substantially tubular body  12  with opposing ends  11 . The tubular body  12  is formed from first and second films  14  and  16  positioned coextensively with one another. The first and second films  14  and  16  are each formed with a laminate construction of one or more layers of select materials as will be described hereinafter. The inner surfaces of the first and second films  14  and  16  are adapted to facilitate sealing of the films together through suitable sealing means along edge portions  18  thereof. The sealed first and second films  14  and  16  define a sealed chamber  20  (as best shown in  FIG. 2 ) extending longitudinally through the tubular body  12 .  
      The sealed chamber  20  is adapted to retain a quantity of the freezable liquid  22  which may contain one or more active agents (as best shown in  FIG. 2 ) within the packaging  10 . The first and second films  14  and  16  are made of select materials and are fabricated to resist tears and punctures, and withstand the effects normally associated with freezing and thawing of the freezable liquid  22 .  
      The packaging  10  containing the freezable liquid  22  including one or more active agents may be placed in a freezer for a sufficient time to yield a freezer pop containing the active agent. Upon freezing, the freezer pop can be consumed by first opening one of the ends  11  of the tubular body  12 , and thereafter exerting pressure from the opposed end to urge the frozen liquid out of the open end.  
      Referring to  FIG. 2 , the first and second films  14  and  16  are positioned so that opposing inner surfaces  23   a  and  23   b  face one another and thereby form an inner boundary of the sealed chamber  20  which encloses the freezable liquid  22 . The edge portions  18  are maintained in sealing contact with one another at contact areas  19  through suitable sealing means as known in the art (e.g. an adhesive or through heat sealing). The outer surfaces  25   a  and  25   b  of the respective films  14  and  16  which form the exterior surface of the freezer pop and thereby do not contact the freezable liquid may be adapted to permit printing thereon. The printing, for example,may be required instructions for consuming a freezer pop, which contains an active agent. The first and second films  14  and  16 may be transparent to enable the product to be visible to the consumer, if desired.  
      The arrangement and composition of the layers of material forming an embodiment of the packaging will now be explained with reference to  FIG. 3 . Referring to  FIG. 3 , there is shown the relative positioning of the first and second films  14  and  16  of the packaging  10  with the understanding that the dimensions of the different layers comprising first and second films  14  and  16  depicted herein are not drawn to scale or shown in proportion to one another. The first and second films  14  and  16  each include one or more discrete layers of polymer materials arranged to form the sealed chamber  20 , which is occupied by the freezable liquid  22 .  
      The first and second films  14  and  16  each include at least one adhesive layer  24  (a single layer is shown) in contact with the freezable liquid  22 , one or more intermediate layers  26  (a single intermediate layer is shown) overlaying the adhesive layer  24 , and at least one outer layer  28  (a single outer layer is shown) overlaying the intermediate layer  26 .  
      The adhesive layers  24  form the base portion of the laminate film construction of the first and second films  14  and  16  and are the layers which are in direct contact with the freezable liquid through the respective bottom surfaces thereof. The adhesive layers  24  are sealingly engaged to one another along the edge portions  18  of the first and second films  14  and  16 . The adhesive layer  24  may be composed of a suitable adhesive material, including, but not limited to, pressure sealable and/or heat sealable materials such as, for example, low-density polyethylene-linear low-density polyethylene (LDPE-LLDPE). The thickness of the adhesive layer  24  may typically range from about 100 gauge to 400 gauge. The selection of a suitable adhesive material may also provide tear and puncture resistant properties to the packaging. For example, LLDPE is known to exhibit both tear and puncture resistance.  
      One or more intermediate layers  26  overlay the outer surface of the adhesive layer  24 . The intermediate layer  26  draws the adhesive layer  24  and the at least one outer layer  28  together into a single laminate structure, and forms a transition layer to provide a structural bond between the adhesive layer  24  and the outer layer  28  which contributes to providing a desirable child proof product which is both tear and puncture resistant. The intermediate layer  26  is typically composed of material such as low-density polyethylene (LDPE) and has a thickness generally from about 9 to 12 lbs/m 2 , preferably about 10.8 lbs/m 2 .  
      The at least one outer layer  28  forms the main structure of the laminate film  14  and  16 , and overlays the outside surface of the intermediate layer  26 . The outer layer  28  provides the laminate films  14  and  16  with the structural integrity necessary to provide the packaging  10  with the requisite tear and puncture resistance. The outer layer  28  provides the packaging with tear and puncture resistance sufficient to prevent children from accidentally gaining access to the freezable liquid. Tear and puncture resistance properties for this purpose would be known to those skilled in the art. The outer layer  28  is composed of a tear- and puncture-resistant material such as, for example, polyethylene terephthalate (PET), oriented polypropylene (OPP), and biaxial nylon. The thickness of the at least one outer layer  28  is typically of from about 36 gauge to 200 gauge, and preferably about 92 gauge.  
      The packaging  10  further includes at least one moisture barrier layer  30 , which may be located between the intermediate layer  26  and the outer layer  28  and/or may overlay the outside surface of the outer layer  28 . In the specific embodiment of  FIG. 3 , the moisture layer  30  is positioned in both locations for purposes of illustration. The moisture barrier layer  30  is selected from materials which are capable of providing sufficient moisture barrier properties to the packaging  10  so as to reduce moisture loss from the freezable liquid  22  for an extended period of time, typically up to or exceeding two years. The moisture barrier layer  30  provides the packaging with a water transmission rate of less than 0.25 gms/100 inch 2 /24 hours at 100° F., 90% RH.  
      The moisture barrier layer  30  may be selected from low moisture transmission materials including, for example, low moisture-transmission polymer films such as, for example, polyvinylidene chloride (PVDC), and polychlorotrifluoroethylene (PCTFE), coatings of silicon oxide and/or aluminum oxide and metal foils such as, for example, aluminum foil. The preferred low moisture transmission material is polyvinylidene chloride (PVDC). The moisture barrier layer is typically fabricated with a thickness of up to 2 gauge.  
      The packaging of the present invention is particularly suited to store freezable liquids containing one or more active agents, but may be employed for freezable liquids which do not contain an active agent. Suitable freezable liquid formulations in which an active agent may be added are disclosed in EP 1287747A2, as previously described.  
      The frozen liquid in the form of a freezer pop is preferably fast dissolving. The term “fast dissolving” as used herein means that the frozen liquid dissolves in less than 30 seconds, preferably less than 15 seconds, and more preferably less than 10 seconds, after placing the freezer pop in the oral cavity. To freeze the above-described freezable liquid, the packaging containing the freezable liquid is placed in a freezer at a temperature below 0° C., preferably from −5° C. to −20° C.  
     EXAMPLE  
      A packaging for a freezer pop formulation containing dextromethorphan hydrobromide as an active agent is prepared by forming a packaging comprising two films sealed together to form a chamber for storing the freezer pop formulation.  
      The two films have the same or similar construction to that shown in  FIG. 3 . The adhesive layer is a low-density polyethylene-linear low-density polyethylene (LDPE-LLDPE) having a thickness of about 200 gauge. The intermediate layer is a low-density polyethylene (LDPE) having a thickness of about 10.8 lbs/m 2 . The outer layer is polyethylene terphthalate coated with saran and has a thickness of about 50 gauge.  
      A moisture barrier layer of polyvinylidene chloride is provided on the outer surface of the outer layer and has a thickness of up to 2 gauge. The freezer pop formulation is stored in a holding tank and then passed through a plate heat exchanger for pasteurization. The pasteurized formulation is sent to a stainless steel feed tank. The formulation is loaded into the packaging in a conventional filling device. Such filling devices are commonly known in the art. It is preferred to use a device which is serviced by volumetric pumps. In the present instance the device is comprised of sets of eight bars on a single head feed line. The filing line is serviced by eight volumetric pumps—one for each filling line. The 8-bar set is vertically perforated so that an individual bars may be separated from the rest of the bars for administration.