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Title:
CONTAINERS FOR POWDERED PRODUCTS
Document Type and Number:
WIPO Patent Application WO/2007/086969
Kind Code:
A2
Abstract:
A container 10 has primary seal regions (18-1) and secondary seal regions (18-2) respectively. The container also has a resealable closure device (30).

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Inventors:
MANNING PAUL B (US)
MCGRATH JAMES W JR (US)
Application Number:
PCT/US2006/042552
Publication Date:
August 02, 2007
Filing Date:
October 27, 2006
Export Citation:
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Assignee:
PBM PRODUCTS INC (US)
MANNING PAUL B (US)
MCGRATH JAMES W JR (US)
International Classes:
B65D30/10
Foreign References:
US6709157B2
US5749658A
Attorney, Agent or Firm:
DAVIDSON, Bryan, H. (901 North Glebe Road 11th Floo, Arlington VA, US)
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Claims:

WHAT IS CLAIMED IS:

1. A container comprising: a sealed flexible pouch body defining an interior space; removable primary and secondary seal regions which seal primary and secondary openings into the interior space of the pouch body; and a resealable closure member provided adjacent the primary seal region for resealing the primary opening upon removal of the primary seal region.

2. The container of claim 1 , further comprising a strip thermometer physically attached to the pouch body.

3. The container of claim 1 , wherein the closure member comprises cooperative male and female ribs.

4. The container of claim 1 , wherein the primary and secondary seal regions include respective tear notches.

5. The container of claim 4, wherein the primary and secondary seal regions include respective tear lines to allow the primary and secondary seal regions to be physically removed by tearing the pouch body therealong.

6. The container of claim 1 , wherein the pouch body comprises a pair of bottom gusset walls.

7. The container of claim 1 , wherein the pouch body comprises a pair of opposed pinch regions

8. The container of claim 1 , wherein the pouch body comprises a lip region below the secondary seal region.

9. The container of claim 1 , wherein the pouch body includes a liquid fill line.

10. The container of claim 1 , wherein the pouch body comprises a tube member, wherein the secondary seal region comprises a removable tip region which closes the tube member.

11. The container of claim 10, wherein the tip region is removable from the tube member along a severing line, and wherein the severing line is a region of reduced material thickness of the tube member.

12. The container of claim 1 , wherein the pouch body includes an annular fitting outwardly protruding therefrom, and wherein the secondary seal region comprises a seal layer covering the annular fitting.

13. The container of claim 12, wherein the annular fitting is threaded.

14. The container of claim 13, wherein the threaded annular fitting is adapted to receive an infant nipple assembly.

15. The container of claim 1 , wherein the pouch body includes a handle member.

16. The container of claim 15, wherein the handle member is arcuately shaped.

17. The container of claim 1 , wherein the primary and secondary seal regions are unitary unitary with one another.

18. A prepackaged concentrated or powdered product comprising; a container as in any one of claims 1-17; and a concentrated or powdered product contained within the interior space of the container.

19. The prepackaged product of claim 18, wherein the concentrated or powdered product contained within the interior space of the container is a pharmaceutical or nutritional drink product.

20. The prepackaged product of claim 19, wherein the concentrated or powdered product contained within the interior space of the container is a nutritional drink product selected from the group consisting of adult and pediatric nutritional drinks, infant formula, pre-natal drinks, sports drinks, pediatric electrolytes, liquid foods, veterinary drinks .

21. The prepackaged product of claim 18, wherein the concentrated or powdered product contained within the interior space of the container is infant formula.

22. The prepackaged product of claim 21 , wherein the interior space of the container is substantially oxygen free.

23. A method of reconstituting a concentrated or powdered product, comprising the sequential steps of:

(a) providing a prepackaged concentrated or powdered product as in claim 10;

(b) removing the primary seal region and opening the closure member to expose the primary opening to the interior space of the container;

(c) introducing a reconstitution liquid through the primary opening and into the interior;

(d) resealing the primary opening by closing the closure member;

(e) mixing the reconstitution liquid and the concentrated or powdered product within the container to form a reconstituted liquid product; and

(f) removing the secondary seal region to allow access to the reconstituted liquid product through the secondary opening.

24. The method of claim 23, wherein the concentrated or powdered product contained within the interior space of the container is infant formula, and the reconstitution liquid is water.

25. The method of claim 23, wherein between steps (e) and (f) there is practiced the step of heating the reconstituted liquid product within the container.

Description:

CONTAINERS AND METHODS FOR THE RECONSTITUTION AND DISPENSATION OF CONCENTRATED OR POWDERED PRODUCTS

FIELD OF THE INVENTION

The present invention relates generally to the field of containers. In especially preferred embodiments, the present invention relates to containers and methods which allow for the reconstitution and dispensation of concentrated or powdered products (e.g., potable concentrates or powders, such as pharmaceutical and nutraceutical drink products, including adult and pediatric nutritional drinks, infant formula, pre-natal drinks, sports drinks, pediatric electrolytes, liquid foods, veterinary drinks and the like).

BACKGROUND AND SUMMARY OF THE INVENTION

A variety of potable products are provided in the form of liquid concentrates or powders requiring the consumer to add an additional amount of water in order to reconstitute the product to a form that is ready to consume. There exists a need therefore in the art for a container which allows the product manufacturer to supply such concentrated or powdered products to the market in a sanitary, modified atmospheric and hermetically sealed environment while also allowing the consumer to easily reconstitute the product and dispense it once reconstituted from the same manufacturer-supplied container. It isJowards fulfilling such a need that the present invention is directed.

Broadly, the present invention is embodied in containers which are especially adapted for the reconstitution and dispensation otconcentrated or powdered products. In especially preferred embodiments, the

containers of the invention include a sealed flexible pouch body defining an interior space, removable primary and secondary seal regions which seal primary and secondary openings into the interior space of the pouch body, and a resealable closure member provided adjacent the primary seal region for resealing the primary opening upon removal of the primary seal region. A strip thermometer may be physically attached to the pouch body so as to provide visual temperature indication of the reconstituted liquid product within the container.

Most preferably, the closure member includes cooperative male and female ribs, while the primary and secondary seal regions include respective tear notches. The primary and secondary seal regions may also include respective tear lines to allow the primary and secondary seal regions to be physically removed by tearing the pouch body therealong.

The pouch body may comprise a pair of bottom gusset walls to allow expansion the pouch body and thereby accommodate the desired amount of reconstitution liquid. Although the shape of the container is not critical to the present invention, it is preferred that the pouch body be provided with a pair of opposed pinch regions and/or a lip region below the secondary seal region. Also, in order to ensure proper filling of the reconstitution liquid, the pouch body most preferably includes a liquid fill line.

The containers of the present invention may be prepackaged with a desired amount of concentrated or powdered product for later reconstitution. Thus, in use when it is desired to reconstitute the prepackaged liquid concentrate or powdered product in the container, the primary seal region may be physically removed (e.g., by tearing along its respective tear line) and the resealable closure member opened so to

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expose the primary opening to the interior space of the container. A reconstitution liquid may then be introduced through the primary opening and into the container's interior space. Once the proper volume of reconstitution liquid has been introduced into the interior space of the container (e.g., which may be aided by a visible fill line and/or a clear or temperature-sensitive spot on the pouch film indicative of the proper liquid volume), the primary opening may be resealed by closing the closure member. While the closure member is closed, the reconstitution liquid and the concentrated or powdered product within the container may be mixed (e.g., by agitating the container) so as to form a reconstituted liquid product. Thereafter, removal of the secondary seal region will allow access to the reconstituted liquid product through the secondary opening. As such, the reconstituted liquid product may be dispensed from the container, such as by pouring into another receptacle or through straw inserted into the secondary opening.

These and other aspects and advantages will become more apparent after careful consideration is given to the following detailed description of the preferred exemplary embodiments thereof.

BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWINGS Reference will hereinafter be made to the accompanying drawings, wherein like reference numerals throughout the various FIGURES denote like structural elements, and wherein;

FIGURE 1 is a perspective view, partly in section, of one preferred embodiment of a container in accordance with the present invention which is sealed with a pre-measured amount of a liquid concentrate or powdered product in need of reconstitution prior to consumption;

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FIGURE 2 is a side elevational view of the container depicted in FIGURE 1 but without the product contained therein;

FIGURE 3 is a cross-sectional elevational view of the container depicted in FIGURE 2 as taken along line 3-3 therein;

FIGURES 4-9 schematically represent one preferred technique for reconstituting the liquid concentrate or powdered product within the container depicted in FIGURE 1 ; and

FIGURES 10-12 depict in perspective view alternative preferred embodiments of containers in accordance with the present invention which are sealed with a pre-measured amount of a liquid concentrate or powdered product in need of reconstitution prior to consumption.

DETAILED DESCRIPTION OF THE INVENTION

Accompanying FIGURES 1-3 depict one particularly preferred embodiment of container 10 in accordance with the present invention. As shown the container 10 includes a pouch body 12 having opposed flexible pouch walls 12-1 which define therebetween an interior space 12-2 for holding a pre-measured amount of a liquid concentrate or powdered product 14 in need of reconstitution prior to consumption.

The interior space 12-2 of the pouch 12 is most preferably substantially deoxygenated so as to prolong the shelf life of the product 14 contained therein. More particularly, the interior space 12-2 may be filled with a suitable inert gas (e.g., nitrogen, argon, carbon dioxide or the like). Alternatively, the interior space 12-2 may be evacuated (e.g., a vacuum) which would then also serve the beneficial function of assisting to 5 maintain the pouch walls 12-1 in a collapsed state which would thereby

minimize the size of the container 10 for purpose of shipment and/or storage prior to reconstitution of the product 14 therein.

The material forming the pouch walls 12-1 of the container 10 is sealed along the entirety of their opposed edges by means of heat- sealing, adhesive and/or ultrasonic welding to form a sealed edge region

12-3. Gusset walls 12-4, 12-5 are formed at the bottom of the pouch 12 so as to permit the opposed pouch walls 12-1 to expand somewhat and thereby provide a sufficient volume of space 12-2 to accommodate the product 14.

The pouch walls 12-1 may also be provided with a measurement marking 12-6 or "fill line". The fill line 12-6 may be printed on, embossed into or otherwise formed integrally with the material of the pouch walls 12- 1 so as to assist the end user to determine the proper amount of reconstitution liquid (e.g., water, fruit juice, milk or the like) to be added to the concentrated or powdered product 14 to thereby ensure the proper final liquid concentration.

Alternatively (or additionally), the pouch walls 12-3 may be provided with one or more indicator windows 12-6' to assist the user in determining the proper volume of reconstitution liquid to be added. Such indicator windows 12-6' may thus be advantageous if the pouch walls 12-1 are formed of an opaque film material. The indicator window 12-6' may be, for example, transparent or translucent to allow a user to visibly determine when the reconstitution liquid has reached the proper level within the interior 12-2. The indicator window 12-6' may alternatively be a temperature-sensitive indicator which serves to provide a visual indication of the presence of the desired liquid volume.

In the event the reconstituted product 14 is to be served heated (e.g., by the addition of heated water or the heating of the entire container and reconstituted product 14 under running hot water, in a hot water bath or in a microwave oven as may be needed for reconstituted infant formula), the pouch 12 may optionally be provided with a strip thermometer 16 having temperature indicators 16-1 , 16-2 and 16-3 formed of reversible temperature-responsive liquid crystal materials. By way of example only, if the reconstituted product 14 is infant formula, the temperature indicators 16-1 and 16-3 may respectively be colored blue and red to indicate a temperature of the heated reconstituted product 14 that is less than or greater than the ideal temperature for an infant's consumption (e.g., less than or greater than 98.6 0 F (+/- 3 0 F), respectively) while the indicator 16-2 may be colored green to indicate that the temperature is at the desired infant consumption temperature (e.g., about 98.6 0 F (+/- 3 0 F)). One of the temperature indicators 16-1 , 16-2 or 16-3 may also serve the concurrent function of being a visible liquid fill indicator in the manner described above with reference to the window 12-6'. Strip thermometers having temperature indicators formed of reversible temperature-responsive liquid crystal materials are well known and available from numerous commercial sources such as from Dry Pak

Industries of Studio City, CA. See in this regard, the strip thermometers at www.drypak.com, the entire content of which is expressly incorporated hereinto by reference.

Any material suitable for use with the particular product 14 within the container 10 in its concentrated (partially hydrated), dehydrated

(powdered) and fully hydrated (drinkable) forms may be employed to form the pouch walls 12-1. In this regard, virtually any sheet-formable thermoplastics material may be employed in the practice of this invention,

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including (but not limited to) polymers and copolymers of polyolefins (such as polypropylenes, polyethylenes and the like), polyesters, polyamides (e.g., nylons), polyphenylene oxides, polyphenylene sulfides, polyvinyl chlorides, acrylonitriles and the like. Blends of such thermoplastics materials may also be employed in any desired blend ratio to suit desired end use applications. In addition, metal foils, e.g., aluminum, may also be employed in the practice of the present invention. Particularly preferred for the ultimate fabrication of containers for use in the present invention are food grade polyolefins, with polyethylenes being particularly preferred.

It is especially desirable that the material forming the pouch walls

12-1 should formed of a food grade material having oxygen barrier properties. By the term "oxygen barrier" is meant a material that exhibits an oxygen permeability according to ASTM D-1434 of less than about 0.010, preferably less than about 0.005, and most preferably less than 0.003 cc.mil/100 in 2 /24 hrs./atm. at 65% relative humidity (RH) and 68°F.

Such oxygen barrier materials along with the inert gas-filled interior space, will ensure that the powdered product 14 contained in the interior space of the containers 10 will be subjected to a substantially oxygen free (i.e., less than about 1.5% O 2 ) environment thereby prolonging its shelf life. In this regard, when the powdered product 14 is infant formula, it is especially desirable to have an environment within the interior space 12-2 of the containers 10 which contains less than about 0.1% O 2 ).

The oxygen barrier materials may be a thermoplastics material or may be a metal foil. A metallized layer on thermoplastics material is also envisioned so as to achieve the desired oxygen barrier properties. The pouch walls 12-1 may thus be formed of a monolayer of an oxygen barrier material per se, or may be multiple layers of materials wherein one or more such layers are oxygen barrier materials and one or more other

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layers are formed of non-oxygen barrier materials. Suffice it to say, that the selection of any particular oxygen barrier material is dependent upon a number of factors, including the desired container properties and its end use application.

Exemplary classes of oxygen barrier thermoplastics materials include ethylene vinyl alcohol (EVOH) copolymers (e.g., commercially available from Eval Company of America under the registered trademark EVAL ® ', polyvinyiidene chlorides (e.g., commercially available from Dow Chemical under the registered trademark SARAN ® ), oriented and non- oriented polyamides (e.g., nylon 6), and oriented polyesters.

One particularly preferred multilayer thermoplastic film that may be employed in the practice of the present invention is disclosed in U.S. Patent No. 6,093,462, the entire content of which is expressly incorporated hereinto by reference.

Important to the present invention, the container 10 of the present invention includes a primary access opening 18 (see FIGURE 5) and a secondary access opening 20 (see FIGURE 9), each being sealed by a corresponding portion of the edge seal region 12-3 to establish primary and secondary seal regions 18-1 and 20-1 , respectively. These primary and secondary seal regions 18-1 , 20-1 are in turn provided with respective tear notches 18-2, 20-2 to allow the pouch walls 12-1 in the vicinity of each seal region 18-1 , 20-1 to be torn along the tear lines 18-3, 20-3, respectively. Removal of the seal regions 18-1 , 20-1 by tearing the pouch walls 12-1 along the tear lines 18-3, 20-3 will therefore expose the interior space 12-2 to access from the exterior of the container 10 via the primary and secondary openings 18, 20, respectively.

Also important to the present invention is the provision of an integral resealable closure device 30 which is most preferably comprised of interlocking male and female rib elements 30-1 , 30-2, respectively. The rib elements 30-1 , 30-2 may be pressed together manually to form a fluid-

5 tight seal at the primary access opening 18, but may be readily separated from one another by a separatory force to again establish access from the exterior to the interior space 12-2 of the container 12. Virtually any known closure device 30 may be employed in the practice of the present invention such as those disclosed in U.S. Patent Nos. 3,198,228, o 4,812,056, 4, 186,786 and 6,826,808 (the entire content of each such patent being expressly incorporated hereinto by reference).

While the exact shape of the container 10 is not critical to the present invention, it is most preferred that the container 10 in the depicted embodiment include a pair of opposed pinch regions 10-1 which define 5 therebetween a region of lesser cross-sectional dimension to assist the user in grasping and manipulating the container 10. In addition, the container 10 most preferably includes a lip region 10-2 located immediately below the secondary seal region 20-1. The lip region 10-2 provides a surface which can be brought to bear against an edge of 0 another receptacle when the reconstituted liquid is being discharged from the interior space 12-2 through the secondary opening 20. In such a manner, therefore, the lip region 10-2 assists the user in steadying the container 10 while its contents are being discharged.

It is also preferred that the container 10 in the depicted 5 embodiment be configured such that the secondary seal region 20-1 extends laterally outwardly so as to form a spout of sorts when the secondary seal region 20-1 is removed to expose the secondary opening 20. As will be explained in greater detail below, such a spout-iike

configuration will more easily assist the user in pouring the reconstituted liquid product from the container 10 and into another receptacle (e.g., a drinking glass, an infant bottle or the like).

In addition, it is preferred that the secondary opening 20 be considerably smaller in size as compared to the primary opening 18.

Providing the primary opening 18 with a greater size will more easily allow reconstitution liquids to be introduced into the interior space 12-2 of the container 10 through the primary opening 18. On the other hand, providing the secondary opening 20 with a lesser size will permit the user to exercise greater control when discharging the contents therethrough and/or provide an access port through which a straw may be inserted should it be desired to consume the reconstituted liquid directly from the container 10.

As briefly noted above, the container 10 according to the present invention is especially well suited and adapted to allow for the reconstitution and dispensation of concentrated or powdered products. Accompanying FIGURES 4-9 schematically depict one possible technique for reconstituting a concentrated or powdered product 14. In this regard, the product 14 depicted in FIGURES 4-9 may be referred to as infant formula, but it should be kept in mind that such a reference is for mere example only. Thus, the technique depicted in FIGURES 4-9 may sometimes be discussed in terms of reconstituting such concentrated or powdered infant formula 14 in preparation for feeding an infant. Again, such description is exemplary only and may be applied to the reconstitution and dispensation of virtually any concentrated or powdered product.

As depicted in FIGURE 4, when it is desired to reconstitute the concentrated or powdered product 14 within the container 10, a user grasps the container 10 and physically removes the primary seal region 18-1 by tearing it along the tear line 18-3. As shown in FIGURE 5, applying a separatory force to the closure device 30 will therefore expose the primary opening 18 and allow reconstitution liquid RL (e.g., water, juice, milk or the like) to be introduced therethrough and into the interior space of the container 10. Once a volume of the reconstitution liquid RL has been introduced into the container 10 sufficient to fill it to the fill line 12-6, the user may pinch the closure device 30 together so as to reseal the primary opening 18 against fluid leakage (see FIGURE 6).

With the primary opening 18 sealed by the closure device 30 and the secondary opening 20 being sealed by the secondary seal region 20- 1 , the user may physically agitate the entire container so as to thoroughly mix the reconstitution liquid RL and the product 14 so as to form a reconstituted liquid product LP as shown in FIGURE 7. Thus, the resealed closure device 30 and the secondary seal region 20-1 provide the container 10 with liquid sealing characteristics so that the reconstituted liquid product LP may be formed therein without leakage.

At this stage, the user may warm the reconstituted liquid product

LP if desired or necessary. In this regard, hot water may be run over the exterior of the liquid-filled and sealed container 10 or the entire container 10 may be placed physically in a water bath or subject to microwave energy to warm its contents of liquid product LP. Once the desired temperature indication is visible from the strip thermometer, the container

10 may be prepared for dispensing its contents of liquid product LP. In this regard, as depicted in FIGURE 8, a user may gain access to the secondary opening 20 by physically removing the secondary seal region

20-1 along the tear line 20-3. The user may then discharge the reconstituted liquid product LP through the secondary opening 20 and into another receptacle R. In this regard, if the reconstituted liquid product is liquid infant formula, the receptacle R may be an infant bottle or a flexible infant bottle liner to be placed in a bottle sleeve and capped with a suitable nipple for feeding an infant. However, as noted previously, if the liquid product is a non-infant consumable drink, the user at this stage may discharge the reconstituted liquid product LP into drinking glass or cup for consumption or may consume the liquid product LP directly from the container 10 by inserting a straw through the secondary opening 20.

Suffice it to say, that those skilled in the art will recognize many beneficial uses and techniques for reconstituting concentrated or powdered product and dispensing a liquid therefrom once reconstituted.

FIGURES 10-12 depict in perspective view alternative preferred embodiments of containers in accordance with the present invention which are sealed with a pre-measured amount of a liquid concentrate or powdered product in need of reconstitution prior to consumption. In this regard, as compared to container 10 discussed previously, the container 100 depicted in FIGURE 10 most preferably includes a substantially rigid tube member 102 which protrudes laterally outwardly from the pouch body

12. The tube member is most preferably integrally molded to a collar portion 104 of the pouch body 12 at a location below the closure member 30. A tip region 102-1 may be severed from the tube member (e.g., using scissors, knife or like sharp cutting implements) along a severing line 102- 2 so as to expose the interior of the tube member 102 to the exterior environment. In such a manner, the user may gain access to the reconstituted product in a manner similar to that described previously with respect to container 10 for purpose of consumption.

The severing line 102-2 may be provided with a region of weakness to reduce the material thickness along the severing line 102-2 (e.g., via scoring). so that the need for a sharp cutting tool can be avoided. If such a region of weakness is provided along the severing line 102-2, therefore, the user will need only to effect relative twisting or like force application between the tip region 102-1 and the tube member 102 so as to break the tip region 102-1 physically from the tube member 102.

The container 200 depicted in accompanying FIGURE 1 1 is similar to the containers 10 and 100 discussed previously, except that the pouch body 12 is provided with an integrally molded rigid annular fitting member

202 protruding laterally outwardly therefrom. The opening to the fitting member 202 is sealingly covered by a suitable peel-off secondary seal layer 204 formed of a suitable film or cover stock material so as to preserve the hygienic and sterile environment within the pouch body 12. To facilitate manual removal by the end user, the secondary seal layer

204 may be provided with an outwardly extending tab 204-1.

As depicted in FIGURE 11 , the fitting member 202 just happens to be in the form of a threaded male fitting so as to accept the female fitting 206-1 associated with a conventional infant feeding nipple assembly 206. Thus, the embodiment of the container 200 depicted in FIGURE 11 may be employed by the end user as a self-contained infant feeding system whereby the reconstituted product within the pouch body 12 may be an infant formula. The end user may thus reconstitute such infant formula in the manner described above and thereafter remove the seal layer 204 so that the nipple assembly 206 may be threadably engaged with the fitting member 202. The user may then substantially invert the container 200 and present to the infant in need of feeding.

The container 300 depicted in accompanying FIGURE 12 comprises an arcuately shaped handle member 302 protruding outwardly from and being integrally molded with the pouch body 12. Thus, as depicted the handle member 302 includes an upper end region 302-1 which is integrally attached to the pouch body 12 in the vicinity of the closure member 30 and a lower end region 302-2 which is integrally attached to the pouch body at a lower location as compared to the upper end region 302-1. The spaced relationship of the upper and lower end regions 302-1 , 302-2, respectively, and the preferred arcuate shape of the handle member 302 establishes a space 302-3. In such a manner therefore, the end user to more easily grasp and manipulate the pouch body 12 via the handle member 302.

As will also be observed from FIGURE 12, the primary and secondary seal regions unitarily provided by means of the seal region 304. Thus, in use, the seal region 304 may be removed by physically tearing the same along the tear line 304-1. Removal of the seal region 305 will thus expose the interior of the pouch body 12 to allow introduction of the reconstitution liquid in the manner described previously. Thereafter, the closure device 30 may be reclosed to allow the contents of the pouch body 12 to be mixed thoroughly, following which the closure device 30 may be opened partially along a forward end region 305 thereof. Such partial opening of the forward end region 305 of the closure device 30 therefore structurally functions as a secondary sealing region similar to the containers 10, 100 and/or 200 described previously, with the principal exception being that the forward end region 305 may be resealed. Such functionality of the forward end region 305 therefore allows the end user to employ the container 300 in the form of a resealable pitcher.

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While the invention has been described in connection with what is presently considered to be the most practical and preferred embodiments, it is to be understood that the invention is not to be limited to the disclosed embodiments, but on the contrary, is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the appended claims.