Flexible package provided with a snap closure

Abstract: A snap closure for a flexible, gusseted package and a flexible gusseted packing including the closure. The package (500) includes a mouth portion arranged to be opened to provide access to the contents of the package. The package is formed of a flexible material and includes a front panel (26), a rear panel (28) , and a pair of opposed side gussets. The panels and gussets each include a top portion, which between them define the package's mouth. The package's mouth is initially sealed but arranged to be opened, e.g., peeled apart. The snap closure enables the resealing of the mouth of the package and is made up of a pair of elongated elements (402A,402B), one of which includes a tongue (212) extending along the length of it. The other element includes an undercut groove (60) extending along the length of it. The elements (402A,402B) are arranged to be pressed together, whereupon the tongue (212) of the one element enters the groove (60) of the other element with portions of the panels and side gussets tightly interposed therebetween. The closure elements (402A,402B) may be longitudinally rigid or may be segmented to flex in the longitudinal direction to facilitate opening. Moreover, the closure elements (402A,402B) are secured to the panels via an adhesive (502A,502B) covering their entire inner surface. When the closure is utilized it recloses the mouth of the package (500) to preclude or minimize the ingress of air into the package (500).

Description: This invention relates generally to flexible packages, and more particularly to flexible packages for holding products, such as foods, under vacuum therein, and which once opened are arranged to be repeatedly re-opened and re-closed, while keeping the contents fresh. Various types of flexible packages for holding particulate materials, e.g., ground or whole bean coffee, chemicals, etc., under vacuum therein have been disclosed in the patent literature and are commercially available today. Examples of such packages are found in the following United States Letters Patent: 4,576,285 (Goglio), 4,705,174 (Goglio), and 4,913,561 (Beer). The major advantages of flexible packaging, as compared to relatively rigid packaging, e.g., cartons, are that until the flexible package is filled it takes up very little volume, and after it is emptied of its contents it readily collapses, thereby reducing its volume to approximately that of the unfilled package. The former characteristic is a significant advantage insofar as storage is concerned, while the latter characteristic is a significant advantage from the standpoint of being disposable. One common type of flexible package for holding goods under vacuum until the package is opened is the so-called "gusseted" package or bag. Typically such a package is formed from a web of flexible stock material, e.g., polyethylene, polyester, polypropylene, metal foil, and combinations thereof in single or multiple plies, into a tubular body, having a face panel, a back panel, and a pair of gusseted sides. Each gusseted side is formed by a pair of gusset sections and a central fold edge interposed between a pair of outer fold edges. The lower end of the bag is commonly permanently sealed, e.g., heat sealed, along a line extending transversely across the width of the bag close to its bottom edge. The top of the bag is commonly sealed transversely across the entire width of the bag in a number of ways to maintain the contents under vacuum until the bag is opened. Such action is frequently accomplished via a readily openable mouth, which when opened provides access to the contents of the bag. For example, in one prior art package the top seal is made peelable by modifying the sealant layer with a peelable coating or incompatible additive. Thus, when the seal is peeled apart the unsealed portions form an open mouth through which the contents of the package may be removed. Another approach to providing an opening or mouth for a flexible package is that of the heretofore identified Patent No. 4,705,174 (Goglio). That package includes a peel strip applied to the inner surface of the package below the top edges. The strip provides an air-tight interfacial seal which can be readily peeled apart to provide access to the interior of the package. Another approach to providing an opening or mouth for a flexible package is to score the upper flap of the package by laser or mechanical means through a tear initiation resistant layer(s) of the package structure. In this way the package can be opened by tearing away the scored area to form the package's mouth. Gusseted bags, particularly those for foods, frequently make use of a plastic coated wire tie to serve as closure for the bag. In particular, the wire tie is designed to close the mouth of the bag after it has been initially opened so that the re-closed bag will keep its contents fresh. Whether or not such wire-tie closures effectively provide a positive means of re-closing a gusseted package is open to debate. Moreover, the effectiveness of such closures is frequently dependent upon the manner in which the wire tie is used. Thus, there is a perception in some quarters of the consuming public that a wire-tie package cannot be re-closed securely enough to maintain product freshness over an extended period of time. Therefore, such packages have not been fully accepted as being truly reclosable. Non-gusseted flexible packages, such as stand-up pouches, are commercially available and typically include so-called "zipper-type" closures. Examples, of such packages are shown in United States Letters Patent Nos. 5,059,036 (Richison et al.), and 5,147,272 (Richison et al.). These zipper-type closures are generally perceived by the consuming public as providing for a more effective reclosure of the flexible pouch after it has been initially opened than twist or wire tie closures. In fact, zipper-type closures may be more effective than wire-tie closures. At the very least they are easier to use, and not prone to loss or misplacement. Thus, stand-up, flexible pouches with zipper-type closures have gained wide acceptance by the consumer. While the stand-up, zipper-closure type pouch offers advantages over a gusseted flexible package insofar as actual or perceived reclosability is concerned, its shape does not allow efficient use of case packing and retail shelf space, as does a gusseted package. In addition, the stand-up pouch cannot be stacked readily, if at all. In United States Letters Patent No. 5,692,837 (Beer), which is assigned to the same assignee as this invention there is disclosed a gusseted flexible package having a integrated snap closure for re-closing and resealing the package after it has been initially opened. In particular, that package has an interior for initially holding some product, e.g., whole coffee bean or ground coffee, under vacuum, and which includes a mouth portion arranged to be peeled open to provide access to the contents of the package. The package is formed of a flexible material and includes a front panel, a rear panel, and a pair of opposed side gussets. The panels and gussets each include a top portion, which between them define the package's mouth. A peelable closure is provided within the mouth. A snap closure is provided above the peelable closure. The package is arranged to be sealed under vacuum, with the peelable closure maintaining the vacuum within the package until it is peeled open. The snap closure comprises a pair of snap strip members secured to respective portions of the front and rear panel. The snap strip portions are arranged to be releasably snap fit together with portions of the closure extending through opening in the side gussets, so that the snap strip portions can be opened and re-closed after the peelable closure has been peeled open in order to provide repeated access to the interior of the package, while minimizing the ingress of air into the package when it is closed. Other references involving closures for packages are found in United States Letters Patent Nos.: 4,988,216 (Lyman), and 5,037,138 (McClintock et al.), and in Japanese Application 6127557 (5/1994), and United Kingdom Patent 1,008,068 (10/1965) US Patent no. 3,346,883 to Ersek discloses a disposable sample bag made of flexible plastics material and having a mouth for providing access to the interior of the bag, and a snap-closure for closing the bag after it has been used. The closure comprises two circuate elongate members secured to respective sides of the bag and engageable one within the other, with portions of the bag therebetween, to close the bag. US-A-3,346,883 discloses all features of the preamble of claim 1. While the inventions of the aforementioned prior art are suitable for their intended purposes, a need still exists for snap closures for use on gusseted packages and for gusseted packages which include snap closures not requiring holes or openings in the gussets of the package to effect re-closure of the package. Accordingly, it is a general object of this invention to provide another gusseted flexible package which addresses the needs of the prior art. It is a further object of this invention to provide a gusseted flexible package which includes a snap closure. It is a further object of this invention to provide a gusseted flexible package with a snap closure which is simple in construction. It is a further object of this invention to provide a gusseted flexible package which includes a snap closure and which is low in cost. It is a further object of this invention to provide a gusseted flexible package which includes a snap closure and which can be manufactured easily. It is a further object of this invention to provide a gusseted flexible package which includes a snap closure and which is easy to use. It is a further object of this invention to provide a gusseted flexible package which includes a snap closure that does not require openings in the gussets in order to operate to seal the package. These objects are achieved by providing a flexible package according to claim 1. Advantageously, said first and second closure elements extend substantially the full width of said first and second panels. Preferably said panels are connected to each other by respective side gussets. The first and second closure elements may be formed of a plastics material. Preferably, said package is formed of a material enabling the contents of said package to be maintained under vacuum when said package is sealed. Advantageously, said package includes a seal, for example a peelable seal, at said mouth for sealing said package to maintain the contents of said package under vacuum. Advantageously, the first closure element comprises said tongue and at least one flange extending along the tongue and connected thereto by a hinge portion, the flange projecting towards the channel portions when the tongue is disengaged from said channel and being arranged to be pushed back by the channel portion when the tongue fully enters the channel for the flange to move about the hinge portion and to lie flat thereby to provide a visual indication that said tongue portion is fully within said undercut channel portion. Said segment sections may be formed by a plurality of slits extending perpendicularly to said longitudinal axes. Said slits may be equidistantly spaced from each other. Advantageously, said panels are connected to each other by gusseted side panels for increasing the width of the mouth of the package and hence facilitating access to said interior thereof, and further for being folded in between the first and second panels and tightly engaged with the first and second closure elements to seal the package. Said tongue and said channel may each have a cross-sectional shape comprising a relatively narrow neck portion projecting from the respective flange and, at the outer end of the neck portion, a wider portion for the wider portion of one of the tongue and channel to interlock with the wider portion of the other. For better understanding of the invention and to show how the same may be carried into effect, reference will be made, by way of example, to the accompanying drawings, in which: Fig. 1 is an isometric view of a flexible gusseted package including a closure, the package being shown in the state prior to being initially opened; Fig. 2 is an enlarged isometric view taken from one side of the package of Fig. 1 showing the package after it has been initially opened to provide access to its interior; Fig. 3 is enlarged isometric similar to Fig. 2, but taken from the opposite side of the package; Fig. 4 is an enlarged sectional view taken along line 4 - 4 of Fig. 1; Fig. 5 is an enlarged sectional view like that of Fig. 4, but showing the package in the process of being resealed or re-closed using the package's closure; Fig. 6 is an isometric view of a separate closure for use on a conventional flexible gusseted package, with only the top portion of the package being shown; Fig. 7 is an isometric view of another flexible gusseted package including a closure, the package being shown in the state prior to being initially opened; Fig. 8 is an enlarged isometric view taken from one side of the package of Fig. 7 showing the package after it has been initially opened to provide access to its interior; Fig. 9 is an enlarged sectional view taken along line 9 - 9 of Fig. 7; Fig. 10 is an enlarged sectional view similar to that of Fig. 9, but showing the package in the process of being resealed or re-closed using the package's closure; Fig. 11 is a sectional view, like that of Fig. 4, but showing another flexible gusseted package including a closure being shown in the state prior to being initially opened; Fig. 12 is a sectional view, like that of Fig. 5, but showing the package of Fig. 11 in the process of being resealed or re-closed using the package's closure; Fig. 13 is an exploded isometric view of still another flexible gusseted package including a closure; Fig. 14 is a reduced top plan view of the package shown in Fig. 13, shown in its sealed configuration; Fig. 15 is top plan view, similar to Fig. 14, but showing the package of Fig. 13 in its open or unsealed configuration; and Fig. 16 is a vertical sectional view of the top portion of a package constructed in accordance with this invention showing the package in its open or unsealed configuration. Referring to Fig. 1, there is shown at 20 in Fig. 1 a flexible package. The package 20 basically comprises a gusseted bag 22 and a re-sealable closure 24. The bag 22 is arranged to hold any material, e.g., coffee beans, ground coffee, chemicals, etc., for dispensing therefrom. The bag 22 is formed of a web of any suitable, flexible material in a manner to be described hereinafter. Turning now to Figs. 1 - 3 it can be seen that bag 22 basically comprises a front wall or panel 26, a rear wall or panel 28, a pair of identical gusseted sides 30 and 32, a top end portion 34, and a bottom end portion 36. The top end portion 34 of the bag terminates in a top marginal edge 38. In a similar manner the bottom end portion 36 terminates in a bottom marginal edge (not shown). If desired, a one-way venting valve (not shown) may be included in any suitable portion of the package to enable gases which may be produced by the material(s), e.g., coffee, contained within the sealed package to vent to the ambient air without air gaining ingress to the package's interior. The front panel 26, rear panel 28, and the two gusseted sides 30 and 32 of the bag are all integral portions of a single sheet or web of the flexible material, of single or multiple ply or layers, which has been folded and seamed to form a tubular body. One particularly useful flexible material for the bag 22 is a laminated web of flexible packaging material commercially available from Fres-Co System USA, Inc., of Telford PA, the assignee of this invention. That material comprises a 48 gauge polyester layer, ink, an adhesive layer, a 28 gauge aluminum foil layer, another adhesive layer, a 60 gauge nylon layer, another adhesive layer, and a 300 gauge easy open sealant layer. When a web of such material is formed into the tubular body for the package the polyester layer serves as the outer surface of the package, with the easy-open sealant layer being the inner surface of the package. As can be seen clearly in Figs. 1 - 4, the closure 24 is located at the top end portion 34 of the bag 22. The details of the closure 24 will be described later. Suffice it for now to state that the closure 24 includes two strips 24A and 24B which extend across the width of the package's panels 24 and 26, with portions secured on the outer surface thereof in the top portion of the bag below its top edge 38. The package 20 is arranged to be initially hermetically sealed closed along a transverse seal line 40, after it has been filled and vacuumized. The seal line 40 may be permanent or openable (e.g., peelable) and may be formed in any conventional manner. If the seal line is peelable it may be located at any location either above, below, or aligned with the closure 24. In such an embodiment the package can be readily opened by merely grasping the top edges of the front and rear panels and pulling them apart to cause the peelable seal line to open, thereby forming a mouth for the package to provide access to the interior of the package. If the seal line is permanent it should be located above the closure 22 with some space between it and the closure so that the package can be severed along a line between the seal line and the closure to thereby form the package's mouth. In either case, the seal line 40 extends across the width of the package 22 and seals the inner surfaces of the abutting front and rear panels to each other between the inner fold lines 30A and 32A of the gusseted sides 30 and 32, respectively, while sealing the outer marginal portions of the front panel 26 to the portions of the gusseted sides contiguous therewith, while also sealing the outer marginal portions of the rear panel 28 to the portions of the gusseted sides contiguous therewith, as is conventional. Thus, the seal line 40 serves to isolate the contents of the package from the ambient atmosphere once it is sealed. If the seal line 40 is peelable, it may be formed by the appropriate heat sealing of the abutting easy-open sealant layer portions forming the inner surface of the bag 22. Alternatively, a peelable seal line 40 can be formed in any other conventional manner, e.g., the use of peelable sealing strips like that disclosed in the aforementioned Goglio patents. When the package 20 is filled, vacuumized, and sealed its contents, e.g., whole bean coffee (not shown), will be kept isolated from the ambient air by the seal line 40. The closure 24 is also preferably closed, i.e., its strips 24A and 24B being interconnected, at this time although such action is not mandatory. If desired, the top portion 34 of the package may be folded down to form a flap (not shown). The flap may, if desired, be held in place by a strip of adhesive tape (not shown) or some other adhesive means, so that the package is "brick-like" in shape to facilitate stacking or storage. In order to gain ingress into the package so that some or all of its contents can be removed, if the package has a peelable seal line 40, the portions of the front and rear panels of the package contiguous with the top marginal edges 38 of the package are grasped and pulled apart. This action peels open the seal line 40, while also disconnecting or separating the two strips 24A and 24B making up the closure 24, to open the mouth of the package. The contents of the package can then be poured or otherwise removed through the package's mouth. If the package includes a non-openable seal line 40, e.g., a permanent heat seal, then the package can be severed below the heat seal line and above the closure 24. The newly formed top edge of the front and rear panels of the package which were formed by severing action can then be grasped and pulled apart to separate and disconnect the two strips 24A and 24B to open the mouth of the package. The inclusion of the closure 24 as a part of the package (as in Figs. 1 - 5) or the use of a separate closure 100 (as in Fig. 6) with a conventional package enable the mouth of the package to be re-closed or resealed after some of the package's contents have removed. Thus, the package and closure enable one to keep the remaining contents of the package fresh, i.e., generally isolated from the ambient atmosphere. The closure 24, as mentioned above, comprises the pair of strips 24A and 24B which are arranged to releasably mate with each other. Each of the strips is an elongate member formed of a plastic material, e.g., high or low density polyethylene or polypropylene or some other material which is slightly flexible to enable it to be bent out of its original shape by the application of force thereto, but which returns to its original shape after removal of that force. Each strip is arranged to be fixedly secured, e.g welded or permanently adhesively secured to the outer surface of the top portion of a respective one of the panels 26 and 28 of the bag 22 and across the full width of the panel. The construction of the strip 24A can best be seen in Figs. 3 and 5 and includes an elongated planar upper flange 42, an elongated planar lower flange 44 and an intermediate projecting tongue 46. The tongue 46 includes a generally planar top wall 48 and a pair of undercut sidewalls 50 and 52 which merge with the upper and lower flanges 42 and 44, respectively. The planar wall 48 of the strip 24A is fixedly secured to the outer surface of the front panel 26 by a layer of adhesive 54 (Fig. 5). This could be a hot melt adhesive or any other type of adhesive. The construction of the strip 24B can best be seen in Figs. 2 and 5 and includes a lower section formed by an elongated planar flange 56 and, above that, a generally C-shaped upper section 58 defining a channel 60 therein. The free edge of the upper section 56 is in the form of a curved lip 62, but could be in the form of a rounded bead. The flange 56 is fixedly secured to the outer surface of the rear panel 28 of the bag by an adhesive layer 64, e.g., a hot melt adhesive or any other type of adhesive. It must be pointed out at this juncture that the strips 24A and 24B can be mounted and secured to the rear panel 28 and front panel 26, respectively, instead of to the front panel 26 and rear panel 28, respectively, as shown in Figs 1 - 5. Thus, the particular package 20 shown herein is merely exemplary. The material forming the strips is somewhat elastic and/or flexible to enable the tongue 46 of the strip 24A to snap-fit into the channel 60 of the strip 24B, and to be locked therein against accidental disconnection, yet which enable the tongue to exit that recess when the strips are pulled apart. Once the package has been initially opened and a portion of its contents removed, the package can be readily resealed by use of the closure 24 to prevent or minimize the ingress of air into the interior of the package through its mouth. This action is accomplished by merely bringing the strips 24A and 24B into a confronting relationship, as shown in Fig. 5. Then the strips can be squeezed together to cause the tongue 46 to snap into the channel 60 carrying with it contiguous portions of the front panel 26 and side gussets 30 and 32. During this action portions of the front panel 26 and contiguous side gussets bend around the planar wall 48 and undercut sidewalls 50 and 52 of the tongue 46 to be carried into engagement with opposed portions of the rear panel 28 and contiguous side gussets 30 and 32. These engaging panel and gusset portions are forced into the channel 60. As will be appreciated by those skilled in the art since the groove strip 24B is secured to the rear panel 28 only along its lower flange section 56, the portion of the rear panel and contiguous gussets immediately above the securement point 64 can move or slide with respect to the free edge 62 of the strip 24B to be received in the groove 60 as shown in Fig. 4. Notwithstanding their slight elasticity/flexibility, the strips 24A and 24B are substantially rigid so that when they are snapped together as just described, the confronting portions of the tongue and groove serve to sandwich the front panel 26, rear panel 28, and side-gussets 30 and 32 tightly therebetween, thereby producing a substantially air-tight seal. The fact that each of the strips includes flanged portions and other portions projecting from the flanged portions tends to reinforce the strips and keep them linear to further ensure that the mouth of the package is sealed closed when the strips are snap connected to each other. Thus, when the strips 24A and 24B are snapped together the contents of the bag 22 are effectively isolated from the ambient surroundings so that it can be kept fresh over an extended period of time. The package can be readily opened at any time by merely snapping apart (disconnecting) the two strips 24A and 24B. In order to accomplish that action and since the strips are somewhat flexible and resilient, the user of the package can readily grasp any portion of the front panel of the package contiguous with its top edge between the thumb and forefinger of one hand, and grasp any portion of the rear panel of the package contiguous with its top edge between the thumb and forefinger of the other hand to pull the panels apart and to separate the strips. Alternatively, the user can directly grasp one of the strips between his/her thumb and forefinger of one hand and the other strip between the thumb and forefinger of the other hand to pull the strips apart. In either case this action unsnaps the closure, i.e., causes the tongue of strip 24A to snap out of the groove of strip 24B, thereby freeing the panels and providing access to the interior of the package through its mouth. In Figure 6 there is shown an alternative package. This package comprises a gusseted bag like the bag of Figures 1 to 5. However, the closure member is replaced by a closure 100 which is a separate device, i.e., is not an integral part of the flexible package. Instead, the closure 100 is arranged to be mounted or releasably secured to the bag after the bag has been opened to reseal it. The closure 100 is constructed in an identical manner to the closure 24. Although in this case, a gusseted bag is provided, closure 100 could be used on any type of flexible packages. In Figures 1 to 5 and Figure 6, components with the same reference numbers are the same. The closure 100 includes a tongue strip 100A which is identical to strip 24A and a groove strip 100B which is identical to strip 24B. The tongue strip 100A is brought into engagement with the rear panel 28 of the bag while the groove strip 100B is brought into engagement with the outer surface of the front panel 26 of the bag so that its groove 60 is aligned with the tongue 46 of the tongue strip 100A. The two strips 100A and 100B are then pressed together to cause the tongue of strip 100A to enter into the groove of strip 100B carrying with it the contiguous portions of the rear panel 28, front panel 26 and interposed side gussets 32 and 30. In Figs. 7 - 10 there is shown another flexible gusseted package 200. The package 200 includes a gusseted bag 22 constructed in an identical manner to that of the package 20 described heretofore, and an alternative closure 202. Since the bag 22 of the package 200 is identical to the bag of the package 20, the same reference numbers will be used and details of the construction and features of the bag will not be reiterated in the interest of brevity. The closure 202 comprises a tongue strip 202A and a groove strip 202B. The groove strip 202B of package 200 is very similar to the groove strip 24B except for the inclusion of an upper flange as the free end of the upper C-shaped section (as will be described later). The tongue strip 202A of the package 200 is also similar in construction to the tongue strip 24A, except that upper and lower flanges are initially curved or arcuate but are arranged to be flattened out when the two strips of the closure 202 are secured together to provide a visual indication of that fact (as will also be described later). The construction of the strip 202A can best be seen in Figs. 8 and 10. Thus, as can be seen therein the strip 202A is an elongated member which includes an elongated arcuate upper flange section 204, an upper hinge section 206, an elongated arcuate lower flange section 208, a lower hinge section 210, and a central projecting tongue section 212. The tongue section 212 is constructed like the tongue section 46 described heretofore and thus includes a generally planar top wall 48 and a pair of undercut sidewalls 50 and 52 which merge with the upper and lower hinge sections 206 and 210, respectively. As can be seen clearly in Fig. 10 each hinge section 206 and 210 is generally semi-circular in cross section. The planar wall 48 of the tongue shaped strip 202A is fixedly secured along to the outer surface of the front panel 26 in the same manner as described earlier. The construction of the strip 202B is also an elongated member which is best seen in Figs. 8 and 10 and is an elongated channel or recess-shaped member. In particular, the strip 202B includes an elongated planar lower flange section 56 and a generally C-shaped upper section 58 defining a groove or recess 60 therein. The free edge of the upper section 56 is in the form of a planar upper flange 214 terminating in a curved lip 216. The lip may be in the form of a rounded bead. The lower flange section 56 is fixedly secured along to the outer surface of the rear panel 28 in the same manner as described earlier, e.g., by means of a hot melt adhesive 64, any other type of adhesive, a weld joint, etc. The strips 202A and 202B can be mounted and secured to the rear panel 28 and front panel 26, respectively, instead of to the front panel 26 and rear panel 28, respectively, as shown in Figs 7 - 10. Thus, the embodiment of package 200 shown herein is merely exemplary. The material forming the strips is somewhat elastic and/or flexible to enable the tongue 212 of the strip 202A to snap-fit into the groove or recess 60 of the strip 202B, and to be locked therein against accidental disconnection, yet which enable the tongue to exit that recess when the strips are pulled apart. Once the package 200 has been initially opened and a portion of its contents removed, the package can be readily resealed by use of the closure 202 to prevent or minimize the ingress of air into the interior of the package through its mouth. This action is accomplished by merely bringing the strips 202A and 202B into a confronting relationship, like shown in Fig. 10. Then the strips can be squeezed together to cause the tongue to snap into the groove carrying with it contiguous portions of the front panel 26 and side gussets 30 and 32. During this action the hinge sections flatten out, i.e., pivot outward, so that the upper and lower flange portions 204 and 208, respectively, assume a planar configuration to abut the outer surface of the contiguous portions of the front panel 26. At the same time portions of the front panel 26 and contiguous side gussets bend around the top surface 48 and undercut sidewalls 50 and 52 of the tongue 212 of the strip 202A to be carried into engagement with opposed portions of the rear panel 28 and side gussets 30 and 32. These engaging panel and gusset portions are forced into the groove or recess 60 in the strip 202B. As will be appreciated by those skilled in the art since the groove strip 202B is secured to the rear panel 28 only along its lower flange section 56, the portion of the rear panel and contiguous gussets immediately above the securement point 64 can move or slide with respect to the upper flange 214 and its curved free edge 216 of the strip 202B to be received in the groove 60 as shown in Fig. 9. When the tongue 212 is fully within the groove the upper and lower flanges 204 and 208 will be planar as shown in Fig. 9. Notwithstanding their slight elasticity/flexibility, the strips 202A and 202B are substantially rigid so that when they are snapped together as just described, the confronting portions of the tongue and groove serve to sandwich the front panel 26, rear panel 28, and side-gussets 30 and 32 tightly therebetween, thereby producing a substantially air-tight seal. The upstanding and now planar upper flange 204 of the tongue strip 202A and the confronting upstanding flange 216 of the groove strip 202B sandwich portions of the top portion 34 of the bag 22 between them and thus ensure that the top portion 34 of the bag 22 extends upward generally parallel to the front and rear panels of the package. If desired, the groove strip 202B may be constructed so that the upper C-shaped section is constructed like the C-shaped section of the groove strip 24B. In such an embodiment the top portion 34 of the bag 22 may not be oriented so that it is parallel to the front and rear panels of the bag when the closure is in place since the upper flange 204 of the tongue strip 202A will tend to assume its natural arcuate shape, thus bending the top portion of the bag 22 away from it. The fact that each of the strips includes flanged portions and other portions projecting from the flanged portions tends to reinforce the strips and keep them linear to further ensure that the mouth of the package is sealed closed when the strips are snap connected to each other. Thus, when the strips 202A and 202B are snapped together the contents of the bag 22 are effectively isolated from the ambient surroundings so that it can be kept fresh over an extended period of time. As will be appreciated by those skilled in the art, when the package 200 has been effectively resealed by use of its closure 202, i.e. the tongue of the strip 202A is fully seated within the groove 60 of the strip 202B so that an air-tight seal is produced, this fact will be readily apparent to anyone seeing the package since the flanges 204 and 208 of the tongue strip 202A will have assumed a planar configuration. Accordingly, the package 200 provides a visual indication of a good, air-tight reseal. The package 200, like the package 20, can be readily opened at any time by merely snapping apart (disconnecting) the two strips 202A and 202B in the same manner as described earlier. It must be pointed out at this juncture that a separate closure constructed like the closure 202 can be made for releasable securement to any flexible package in the same manner that the closure 100 can be utilized with any type of flexible package. Thus, the closure 202 need not be made as an integral component of a flexible package. In Figs. 11 and 12 there is shown another flexible gusseted package 300 utilizing an alternative closure 302 fixedly secured to a gusseted bag 22. The closure 302 includes a tongue strip 302A and a groove strip 302B. The tongue strip 302A is constructed similarly to strip 24A, except for the inclusion of additional means to enable it to be more securely affixed to its associated bag panel so it cannot accidentally become disconnected. The groove strip 302B is constructed identically to the groove strip 24B of closure 24. Similarly, the gusseted bag 22 is constructed in an identical manner to that of the package 20 described heretofore. Since the bag 22 and the groove strip 202B of the package 300 are identical to the bag 22 and groove strip 24B of the package 20, the same reference numbers will be used and details of the construction and features of those components will not be reiterated in the interest of brevity. The tongue strip 302A is an elongated, integral member which includes all of the features of the tongue strip 24A, except that the lower flange section 44 has been replaced by an alternative lower flange section 304 for use in mounting the strip onto its associated panel instead of using the outer surface of the planar top wall 48 (as is the case with the tongue strip 24A described earlier). The lower flange section 304 basically comprising a living hinge 306 of reduced wall thickness to enable it to bend freely, an inverted projecting tongue portion 308, and a mounting flange 310. The inverted tongue portion 308 is of the same shape as the portion 46 of the strip 302A, i.e., includes a generally planar wall 48 and a pair of undercut sidewalls 50 and 52 which merge with the upper and lower flanges 42 and 310, respectively, except that it faces in the opposite direction therefrom. The lower mounting flange 310 is used to fixedly secure the tongue strip 302A to the panel 26 of the bag 22 via either an adhesive 64 or by being welded or otherwise bonded to the panel. Since the lower mounting flange serves as the means for mounting the strip onto the panel the flange 310 is somewhat similar to the flange 44 of the strip 24A, except that it is of greater height to provide greater contact area for the adhesive or the weldment. When the strip 302A is fixedly secured to the panel 26 and when the closure 302 is open, i.e., the tongue strip is not interlocked to the groove strip, the strip is in the orientation as shown in Fig. 12. In particular, the interface of the flat top 48 and the undercut sidewall 52 of the tongue section 46 of the strip 302A abuts the outer surface of the panel 26. In order to close the package, i.e., cause the two closure strips to interlock, all that is required is to press on the tongue strip to bend and pivot it inward and thereby force the tongue section 46 to enter into the recess 60 in the groove strip 302B to thereby tightly interpose the bag walls therebetween as described earlier. The living hinge 306 facilitates the bending and pivoting of the tongue section from the orientation shown in Fig. 12 to the orientation shown in Fig. 11. The material forming the strips is somewhat elastic and/or flexible to enable the tongue 46 of the strip 302A to snap-fit into the groove or recess 60 of the strip 302B, and to be locked therein against accidental disconnection, yet which enable the tongue to exit that recess when the strips are pulled apart. It must be pointed out at this juncture that the strips 302A and 302B can be mounted and secured to the rear panel 28 and front panel 26, respectively, instead of to the front panel 26 and rear panel 28, respectively, as in the package shown in Figs 1 - 5. Thus, the package 22 shown herein is merely exemplary. The package can be readily opened at any time by merely snapping apart (disconnecting) the two strips 302A and 302B of the closure 302. In order to accomplish that action and since the strips are somewhat flexible and resilient, the user of the package can readily grasp any portion of the front panel of the package contiguous with its top edge between the thumb and forefinger of one hand, and grasp any portion of the rear panel of the package contiguous with its top edge between the thumb and forefinger of the other hand to pull the panels apart and to separate the strips. Alternatively, the user can directly grasp to upper edge portion 62 of the groove strip 302B between his/her thumb and forefinger of one hand and the upper edge portion 42 the tongue strip 302A between the thumb and forefinger of the other hand to pull the strips apart. In either case this action unsnaps the closure, i.e., causes the tongue of strip 302A to snap out of the groove of strip 302B, thereby freeing the panels and providing access to the interior of the package through its mouth. In Figs. 13 - 14 there is shown another flexible gusseted package 400. The package 400 includes a gusseted bag constructed in an identical manner to that of the package 22 described heretofore, and an alternative closure 402. Since the bag of the package 400 is identical to the bag of the package 20, the same reference numbers will be used hereinafter and details of the construction and features of the bag will not be reiterated in the interest of brevity. The closure 402 is identical to the closure 202 described heretofore, except that each of the closure's tongue strip 402A and the groove strip 402B are segmented. By segmented it is meant that each strip 402A and 402B comprises a plurality of segment sections (to be described later) which are disposed along the length (i.e., the longitudinal axis) of the strip and are separated from one another by interposed slits or other means enabling the various segment sections to bend with respect to each other in the longitudinal direction. Since the details of the strips 402A and 402B of the closure 400 are identical to the strips 202A and 202B, respectively, of the closure 202 except for the use of the segmented sections, and in the interest of brevity the common details of the construction of the closure 402 to closure 202 will be given the same reference characters and their description will not be reiterated. The construction of the strips 402A and 402B can best be seen in Fig. 13. In particular, the tongue strip 402A is an elongated member which includes an elongated arcuate upper flange section 204, an upper hinge section 206, an elongated arcuate lower flange section 208, a lower hinge section 210, and a central projecting tongue section 212. The strip 402A is segmented to form a plurality of short length segment sections 404A, each of which is separated from its immediately adjacent section by a slit 406A. Each slit 406A extends partially through the tongue strip 402A in a plane which is perpendicular to the longitudinal axis of the strip 402A. To that end each slit 406A extends fully through the tongue section 212, fully through the adjacent hinge sections 206 and 210, but only partially through the arcuate upper flange section 204 and partially through the arcuate lower flange section 208, to a terminus point 408 immediately adjacent the edges of those sections. The material making up the strip 402A between the edge of the flange 204 and the terminus points 408 forms a plurality of flexure joints 410 thereat. In a similar manner, the material making up the strip 402A between the edge of the flange 208 and the terminus points 408 form a plurality flexure joints 410 thereat. The flexure joints 410 enable the segment sections 404A of the closure strip 402A to flex or bend with respect to the longitudinal axis about them. In accordance with one preferred embodiment of this invention the slits 406A of the strip 402A are equidistantly spaced from one another. The strip groove 402B is an elongated channel or recess-shaped member. In particular, as best seen in Fig. 13, the strip 402B includes an elongated planar lower flange section 56 and a generally C-shaped upper section 58 defining a groove or recess 60 therein. The C-shaped upper section 58 is segmented to form a plurality of short length segment sections 404B, each of which is separated from its immediately adjacent section by a slit 406B. Each slit 406B extends partially through the C-shaped upper section in a plane which is perpendicular to the longitudinal axis of the strip 402B. Each slit terminates at one end in a terminus point 412 closely adjacent the flange 214. The other end of each slit terminates in a terminus point 412 closely adjacent the flange 56. The slits 406B do not, however, extend into the flanges 56 or 214. Thus, each slit terminates in a pair of terminus points 412, one closely adjacent the flange 56 and the other closely adjacent the flange 214. The material making up the strip 402B between the flange 56 and the terminus points 412 forms plural flexure joints 414 thereat. In a similar manner, the material making up the strip 402B between the flange 214 and the terminus point 412 forms a plurality of flexure joints 414 thereat. The flexure joints 414 of the strip 402B enable the segment sections 404B to flex or bend with respect to the longitudinal axis about them. In accordance with one preferred embodiment of this invention the slits 406B of the closure strip 402B are also equidistantly spaced from one another. The strips 402A and 402B are mounted and secured to the front panel 26 and rear panel 28, respectively, or to the rear panel 28 and front panel 26, respectively, depending upon the desires of the manufacturer. Thus, it should be borne in mind that the embodiment of package 400 shown herein is merely exemplary. Moreover, the strips 402A and 402B may be separate components from the package, i.e., be arranged to be mounted on the package when their use is desired and removed from the package when their use is not desired. In either case, the plural flexure joints 414 separating the segment sections of the strips, permit the strips to bend to facilitate the opening of the package on which they are disposed. In this regard, as will be appreciated when the package 400 is initially sealed shut by the peelable seal 40 (not shown in Figs. 13-14), the closure 402 will be in its closed state, i.e., the tongue of strip 402A will be snap-fit within the recess 60 in the strip 402B with the continuous portions of the package's panels interposed tightly therebetween in the same manner as described earlier and as shown in the top view of Fig. 14. In order to open the package the user merely grasps the two closure strips 402A and 402B between the thumb and index finger of each hand to and pulls outward on each. This action has the effect of causing tongue portion 212 of the strip 402A to snap out of the groove 60 in strip 402B. The outward pulling on the two strips also causes the segment sections of those strips to flex about their interposed flexure joints, whereupon the strips 402A and 402B bow outward. The bowing outward of the closure strips such as shown in Fig. 15 causes the peelable seal 40 to open up, thereby opening the mouth of the package so that its contents can be removed through the open mouth. Once the package 400 has been initially opened and a portion of its contents removed, the package can be readily resealed by use of the closure 402 to prevent or minimize the ingress of air into the interior of the package through its mouth. This action is accomplished by merely bringing the strips 402A and 402B into a confronting relationship. Then the strips can be squeezed together to cause the tongue 212 of strip 402A to snap into the groove 60 of strip 402B carrying with it contiguous portions of the front panel 26 and side gussets 30 and 32. During this action the hinge sections 206 and 210 of the strip 402A flatten out, i.e., pivot outward, so that the upper and lower flange portions 204 and 208, respectively, of that strip assume a planar configuration to abut the outer surface of the contiguous portions of the front panel 26. At the same time portions of the front panel 26 and contiguous side gussets bend around the top surface 48 and undercut sidewalls 50 and 52 of the tongue 212 of the strip 402A to be carried into engagement with opposed portions of the rear panel 28 and side gussets 30 and 32. These engaging panel and gusset portions are forced into the groove or recess 60 in the strip 402B. Notwithstanding their flexibility in the longitudinal direction resulting from the flexure joints between the segment sections, the strips 402A and 402B are sufficiently rigid so that when they are snapped together as just described, the confronting portions of the tongue and groove serve to sandwich the front panel 26, rear panel 28, and side-gussets 30 and 32 tightly therebetween, thereby producing a substantially air-tight seal. The upstanding and now planar upper flange 204 of the tongue strip 402A and the confronting upstanding flange 214 of the groove strip 402B sandwich portions of the top portion 34 of the bag 22 between them and thus ensure that the top portion 34 of the bag extends upward generally parallel to the front and rear panels of the package. In Fig. 16 there is shown a package 500 according to the present invention. In particular, the package 500 is of the same basic construction as that of package 400, except that the two closure elements or strips are adhesively secured to their respective bag panels via adhesive covering the entire inner surface of those closure strips. In the interests of brevity the common structural details of packages 400 and 500 will be given the same reference numbers. Thus, as can be seen the package 500 includes a gusseted bag constructed in an identical manner to that of the package 20 described heretofore and a closure constructed in an identical manner to that of package 400. The closure comprises a segmented tongue strip 402A and a segmented groove strip 402B. The tongue strip has an elongated upper flange section 204, an upper hinge section 206, an elongated lower flange section 208, a lower hinge section 210, and a central projecting tongue section 212. The groove strip 402B has an elongated planar lower flange section 56 and a generally C-shaped upper section 58 defining a groove or recess 60 therein. The strips 402A and 402B are mounted and secured to the front panel 26 and rear panel 28, respectively, or to the rear panel 28 and front panel 26, respectively, depending upon the desires of the manufacturer. In either case each strip is adhesively secured to its respective panel over the entire inner surface of the strip. This is achieved by interposing any suitable adhesive layer between the strip and the abutting outer surface of the associated panel. For example, in the exemplary embodiment shown in Fig. 16, the entire inner surface 504A of the tongue strip 402A is adhesively secured by an adhesive layer 502A to the underlying portion of the outer surface of the panel 26. In a similar manner, the entire inner surface 504B of the groove strip 402B is adhesively secured by an adhesive layer 502B to the underlying portion of the outer surface of the panel 28. The package 500 may be readily manufactured by applying the adhesive to the inner surface of the closure strips 402A and 402B, and then pressing them onto their respective panels of the bag. Since the panels 26 and 28 making up the package are flexible, the portions of those panels which engage and become adhesively secured to the underside of the strips 402A and 402B closely conform to the shape or profile of those strips. Thus, the portions of the panels 26 and 28 abutting the strips permanently adopt the inner contour of the respective strip profiles. This action predisposes the strips for easier reclosure of the package. In this regard, the portions of the bag's panels which will be tightly interposed between the strips will be already bent into the proper shape and thus easily located within the C-shaped space defined between the tongue and groove, like shown in Fig. 9. This action will occur without requiring any relative movement between any portion of the strip and the associated panel, as is the case with the closures wherein only portions of their strips are secured to the panels, e.g., the embodiments of Figs. 9, 11, and 13. In addition to providing for easier reclosure of the package, the total adhesive securement of the strips 402A and 402B as just described also permits the use of an alternate and smaller profile design for the closure. Not only is such a smaller profile less costly to manufacture, it also provides a more aesthetically pleasing appearance for the package. Moreover, the total adhesive securement of the strips to their associated panels reduces the chances of accidental disconnection from the package. Though not within the scope of the claims, the total securement of the closure strips to their associated panels is not limited to use in only segmented type closures, like that of Fig. 16. Thus, any of the described closures may be adhesively secured to their associated panels over the entire inner surface of the closure strip to predispose the secured portion of the panels to the contour of the strips. Moreover, the closures of this invention can be used on various types of flexible packages other than those specifically shown herein, e.g., packages which do not include side gussets, such as pouches. In order to facilitate the opening and closing of any of the closures of this invention, either or both of the strips making up the closure may include some surface texture, e.g., ridges, knurls, grooves, etc., to enhance friction when grasped between the fingers of the user of the package. Closures and packages including closures constructed in accordance with this invention offer several advantages over pouch-type packages including conventional zip-lock type or other internally-located closures. For example, the closure may be applied to the pouch, after the pouch has been filled and sealed. Moreover, the closure provides rigid support to maintain the shape and integrity of the package. The closures of this invention, being externally located or applied, do not render the package on which they are used subject to contamination and, hence, ineffective as is a common occurrence with internally applied closures, such as zip-lock type closures. Further still, zip-lock type closures and other internally located heat sealable closures are limited in the types of material from which they can be formed or fabricated, e.g. they must be made of a material which is compatible with the sealant layer of the pouch. The closures of this invention, being located externally, can be formed of any number of materials chosen to meet the requirements of the particular application. As will also be appreciated by those skilled in the art, the closures of this invention can be modified insofar as its construction and/or material composition is concerned in order to accommodate the preferred degree of opening and/or closing pressure required to operate it. Without further elaboration the foregoing will so fully illustrate our invention that others may, by applying current or future knowledge, adopt the same for use under various conditions of service. It will be understood that the closure elements such as 24A and 24B; 100A and 100B; 202A and 202B; and 302A and 302B of Figures 1 to 12 and other developments and modifications thereof may be provided as a plurality of segments as shown in Figures 13 to 15. The number of segments or segment sections (as the case may be) may be large/numerous and the segments/segment sections quite short compared to the length of the or each element. There could be at least three segments, or better at least five or even better at least ten, or even better than that at least fifteen. As can be seen in Figure 15, there could be twenty segments. The packages shown in Figures 1 to 5 and 7 to 15 are not in themselves within the scope of the following claims. However, in these packages the closure elements may be adhered to the adjacent portions of the package so that these portions conform to the shapes of the closure elements as disclosed with reference to Figure 16 and elsewhere and in the following claims. The package of Figure 6 is not within the scope of the following claims. Herein the closure strips are secured to the panels by adhesive. Though not within the scope of the claims, it is hereby disclosed that the strips could be secured by any other suitable means, e.g. by a weld joint or heat seal or coextrusion may be utilised.

Claims: A flexible package having an interior for holding material therein, the package being made of flexible sheet material and having first and second panels (26, 28) which are connected to each other but which have upper end portions that conjoin to form a mouth for providing access to the interior of the package, the package further comprising an integral snap-closure for closing the said mouth of the package, the snap closure comprising two elongate closure elements (402A, 402B) located on respective ones of said panels adjacent said mouth and engageable one with another with portions of said panels interposed therebetween to close the mouth of the package, said first elongate closure element (402A) comprising a tongue (212) and being secured to said first panel (26) over substantially the entire surface of said first closure element adjacent to the first panel including the outer surface of the tongue, whereupon said first panel conforms in shape to said first closure element, said second elongate closure element (402B) comprising a portion defining an undercut channel (58), said second closure element being secured to said second panel (28) over substantially the entire surface of said second closure element adjacent to the second panel including the inner surface of the channel defining portion, whereupon said second panel conforms in shape to said second closure element, said tongue (212) of said first closure element (402A) being operable for being repetitively snap-fittable into and withdrawable from said undercut channel (58) of said second closure element (402B) a plurality of times, portions of said panels being tightly engageable between said closure elements to close the mouth of the package to prevent the ingress of air into the package through said mouth, characterised in that said first elongate closure element (402A) comprises at least one flange (204, 208) projecting from said tongue (212), said first closure element being secured by an adhesive layer (502A) to said first panel (26) over substantially the entire surface of said first closure element adjacent to the first panel including said flange and the outer surface of the tongue, said second elongate closure element (402B) comprising at least one flange (56) projecting from said channel defining portion (58), said second closure element being secured by an adhesive layer (502B) to said second panel (28) over substantially the entire surface of said second closure element adjacent to the second panel including said flange and the inner surface of the channel (58), wherein each of said closure elements has a longitudinal axis and comprising a plurality of short segment sections (404A, 404B), each of said segment sections being flexibly connected to an adjacent segment section to enable each closure element to flex with respect to its longitudinal axis to facilitate the use of said snap closure. The package of Claim 1, wherein said first and second closure elements extend substantially the full width of said first and second panels. The package of Claim 1, wherein said panels are connected to each other by respective side gussets (30, 32). The package of Claim 1, wherein said first and second closure elements each are formed of a plastics material. The package of Claim 1, wherein said package is formed of a material enabling the contents of said package to be maintained under vacuum when said package is sealed. The package of Claim 1, wherein said package includes a seal at said mouth for sealing said package to maintain the contents of said package under vacuum. The package of Claim 6, wherein said seal is peelable. The package of Claim 1, wherein the first closure element comprises said tongue (212) and at least one flange (204, 208) extending along the tongue and connected thereto by a hinge portion (206, 210), the flange projecting towards the channel portion (58) when the tongue is disengaged from said channel and being arranged to be pushed back by the channel portion when the tongue fully enters the channel for the flange to move about the hinge portion and to lie flat thereby to provide a visual indication that said tongue portion is fully within said undercut channel portion. The package of any preceding claim, wherein said segment sections are formed by a plurality of slits (406A, 406B) extending perpendicularly to said longitudinal axes. The package of Claim 9, wherein said slits are equidistantly spaced from each other. The package of any preceding claim, wherein said panels are connected to each other by gusseted side panels (30, 32) for increasing the width of the mouth of the package and hence facilitating access to said interior thereof, and further for being folded in between the first and second panels and tightly engaged with the first and second closure elements to seal the package. The package of any preceding claim, wherein said tongue (212) and said channel (58) each have a cross-sectional shape comprising a relatively narrow neck portion projecting from the respective flange and, at the outer end of the neck portion, a wider portion for the wider portion of one of the tongue and channel to interlock with the wider portion of the other.

Inventors: GALOMB DAVID E, SUTO DAVID K, GALOMB, DAVID E., SUTO, DAVID K.
Applicants: FRES CO SYSTEM USA INC, FRES-CO SYSTEM USA, INC.
Application year: 2000
Main classification: B65D33
IPC codes: B65D33