Abstract:
A flexible side-gusseted package and methods of making the same are disclosed. The package has a central longitudinal axis, a front panel, a back panel, and a pair of gusseted side panels. The front panel is secured to the gusseted side panels along a pair of side seal lines. The back panel is secured to the gusseted side panels along a pair of side seal lines. Each of the seal lines includes a pair of end portions and an intermediate portion. The intermediate portion, e.g., a concave recessed portion, of each side seal line is located closer to the central longitudinal axis than the end portions of the side seal lines to provide a package which is somewhat necked-down at its middle, to facilitate grasping of the package by users.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
       [0001]    This application claims priority from Provisional Application Ser. No. 61/566,847, filed on Dec. 5, 2011, entitled GUSSETED FLEXIBLE PACKAGE WITH SHAPED SIDES AND METHODS OF MAKING THE SAME, which application is assigned to the same assignee as this application and whose disclosure is incorporated by reference herein. 
     
    
     BACKGROUND OF THE INVENTION 
       [0002]    This invention relates to flexible packages and more particularly to gusseted flexible packages and methods of making the same. 
         [0003]    Various types of stand-up flexible packages are known for storing liquids, granular, powders and the like. One such package is the so-called side-gusseted package. It is typically 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 front 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. The lower end of the package 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 package is commonly sealed transversely across the entire width of the package in a number of ways to maintain the contents under vacuum until the package is opened. One example of a side-gusseted package is a bag typically used for packaging coffee. That side-gusseted bag is made from a flexible packaging laminate composed of various layers of plastic films, metal foils and papers bonded together using adhesives and extrusions. The flexible packaging laminate is generally printed or labeled for the package contents and other consumer information. The flexible packaging laminate is normally-produced as sheeting wound onto a roll or rolls which is used to form many packages. The flexible package is formed from the laminate using conventional equipment such as pre-made bag machines, vertical form-fill-seal machines, horizontal form-fill-seal machines and other well known equipment. These machines fold a sheet or sheets of the flexible laminate and seal together some of the edges and leaving a filling mouth. The package is then filled through the mouth and then sealed across the filling mouth to complete the package. The formed and filled side-gusseted package generally takes the shape of a parallelepiped or six-faced polyhedron, though at times the package top may also take the form of a triangular prism. 
         [0004]    As is known package retailers tend to keep the package height at a maximum of 12-14 inches in order to maximize the number of shelves for product display. In order to meet the height restriction, package designers must increase the package width and depth in order to hold the required package contents. The problem with these packages is the difficulty in handling the package by the consumer, especially when attempting to pick the package up using one hand. 
         [0005]    Other types of flexible packages are available to provide easier handling. For example, flat pouches have been made in die-cut shapes. These flat pouches can also have a gusset inserted into the bottom to form a shaped stand-up pouch. However, such shaped flat and bottom gusseted stand-up pouches do not provide the volume or depth that is provided by a side-gusseted package. 
         [0006]    Thus, there is a need for a side-gusseted package which can be permit simple one-handed grasping of the package and still keep the package height restricted as required by retailers. The subject invention addresses that need. 
       SUMMARY OF THE INVENTION 
       [0007]    One aspect of this invention is a side-gusseted flexible package. The package has a central longitudinal axis and comprises a front panel, a back panel, and a pair of gusseted side panels. The front panel has a first side edge, a second side edge, a top edge and a bottom edge. Each of the first and second side edges of the front panel includes an end edge portion and an intermediate edge portion, with the intermediate edge portions of the front panel being located closer to the central longitudinal axis than the end edge portions of the front panel. The back panel has a first side edge and a second side edge, a top edge and a bottom edge. Each of the first and second side edges of the back panel includes an end edge portion and an intermediate edge portion, with the intermediate edge portions of the back panel being located closer to the central longitudinal axis than the end edge portions of the back panel. Each of the gusseted side panels comprises pair of gusset sections connected to each other by a fold line. One of the pair of gusseted side panels is secured between the first side edge of the front panel and the first side edge of the back panel. The other of the pair of gusseted side panels is secured between the second side edge of the front panel and the second side edge of the back panel. The bottom edge of the front panel is secured to the bottom edge of the back panel to form a hollow interior in which a product may be located. The top edge of the front panel is arranged to be secured to the top edge of the back panel to enclose the product within the package. 
         [0008]    Another aspect of this invention constitutes methods of making a plurality of side-gusseted flexible packages. One such method basically entails forming a web of flexible material into a tubular member having a central longitudinal axis and a plurality of sequentially located sections extending along the central longitudinal axis. Each of the sections is arranged to be formed into a respective one of the side-gusseted flexible packages (e.g., is a precursor of the package). Each of the side-gusseted flexible packages comprises a front panel, a back panel, and a pair of gusseted side panels, with the front panel having a first side edge, a second side edge, a top edge and a bottom edge, and with the back panel having a first side edge and a second side edge, a top edge and a bottom edge. Each of the gusseted side panels comprises pair of gusset sections connected to each other by a fold line, with one of the pair of gusseted side panels being connected between the first side edge of the front panel and the first side edge of the back panel, with the other of the pair gusseted side panels being connected between the second side edge of the front panel and the second side edge of the back panel. Portions of the front panel are sealed to portions of the gusseted side panels along respective front panel seal lines at the front panel side edges. Each of the front panel seal lines has an end edge portion and an intermediate edge portion. The intermediate edge portions of the front panel seal lines are located closer to the central longitudinal axis than the end edge portions thereof. Portions of the back panel are sealed to portions of the gusseted side panels along respective back panel seal lines at the back panel side edges. Each of the back panel seal lines has an end edge portion and an intermediate edge portion, with the intermediate edge portions of the back panel seal lines being located closer to the central longitudinal axis than the end edge portions thereof. Portions of the package are cut immediately outside the front and back panel seal lines to produce the side edges of the package and the bottom edges of the front and real panels are sealed together along a bottom seal line. The package may be filled with a product and then sealed by a seal line extending across the top edges of the front and back panels. 
         [0009]    Another method of making a side-gusseted flexible package in accordance with this invention entails forming a front panel and a back panel from a web of flexible material. The front panel has a first side edge, a second side edge, a top edge a bottom edge and a central longitudinal axis located midway between the first and second side edges of the front panel. The back panel has a first side edge and a second side edge, a top edge, a bottom edge and a central longitudinal axis located midway between the first and second side edges of the back panel. A pair of tubes is formed from a web of flexible material, with each of the tubes of the pair having a longitudinal axis and an outer surface. A portion of the outer surface of the pair of tubes is adhesively secured to the back panel with the tubes being spaced from each other and with the longitudinally axes of the tubes extending parallel to the central longitudinal axis of the back panel. The front panel is disposed over the back panel and on portions of the pair of tubes to form a pair of gusseted side panels. Portions of the front panels are sealed to portions the tubes along a pair of front panel seal lines and portions of the back panels are sealed to portions of the tubes along a pair of back panel seal lines to form a body having a pair of gusseted side panels and a central longitudinal axis. The central longitudinal axis is located midway between the gusseted side panels. Each of the gusseted side panels comprises a pair of gusset sections connected to each other by a fold line. Each of the front panel seal lines has an end edge portion and an intermediate edge portion with the intermediate edge portions of the front panel seal lines being located closer to the central longitudinal axis than the end edge portions thereof. Portions of the package immediately outside the front and rear panel seal lines are cut to form the side edges of the package. The bottom edges of the front and back panels are sealed together along a bottom seal line to form a hollow, side-gusseted package having an open top. The package may be filled with a product and then sealed by a seal line extending across the top edges of the front and back panels. 
     
    
     
       DESCRIPTION OF THE DRAWING 
         [0010]      FIG. 1  is a front isometric view of one exemplary side-gusseted package constructed in accordance with this invention; 
           [0011]      FIG. 2  is a rear isometric view of the package shown in  FIG. 1 ; 
           [0012]      FIG. 3  is an isometric view of the package of  FIG. 1 , but shown from the bottom; 
           [0013]      FIG. 4  is a flow diagram showing the steps of one method of making a series of packages like shown in  FIGS. 1-3 ; 
           [0014]      FIG. 5  is a plan view of a portion of a web of flexible packaging material which has been formed into a folded tube having plural sequentially located sections, each of which is arranged to be formed into a respective side-gusseted flexible package, with each of those packages having a front panel, a pair of side gussets, and a back panel, in accordance with a method step shown in the flow diagram of  FIG. 4 ; 
           [0015]      FIG. 5A  is a cross sectional view of the folded tube taken along lines  5 A- 5 A of  FIG. 5 ; 
           [0016]      FIG. 6  is a plan view of the folded tube shown in  FIG. 5 , but after the front and back panels and interposed side gussets of a series of sequentially located sections have been sealed along respective seal lines in accordance with a method step shown in the flow diagram of  FIG. 4 ; 
           [0017]      FIG. 7  is a plan view of the folded, sealed tube shown in  FIG. 6 , but after portions of the front, back and side gussets of the series of sequentially located sections have been die-cut along lines immediately outside of the seal lines in accordance with a method step shown in the flow diagram of  FIG. 4 ; 
           [0018]      FIG. 8  is a plan view of the folded, sealed tube shown in  FIG. 7 , but after the die-cut portions of the sequentially located sections of the tube have been discarded in accordance with a method step shown in the flow diagram of  FIG. 4 ; 
           [0019]      FIG. 9  is a plan view of the die-cut sealed tube shown in  FIG. 8 , but after a bottom seal line has been formed between two sequentially located die-cut sections of the tube in accordance with a method step shown in the flow diagram of  FIG. 4 ; 
           [0020]      FIG. 10  is a plan view of the die-cut sealed tube shown in  FIG. 9 , but after a the tube has been die cut below the bottom seal line of the upper section to thereby separate a section from the tube to form a package to be filled with a product in accordance with a method step shown in the flow diagram of  FIG. 4 ; 
           [0021]      FIG. 11  is a plan view of the separated package of  FIG. 10  which is filled with a product through its open top in accordance with a method step shown in the flow diagram of  FIG. 4 ; 
           [0022]      FIG. 12  is a plan view of the filled package shown in  FIG. 11  after its top end has been sealed to close off the package in accordance with a method step shown in the flow diagram of  FIG. 4 ; 
           [0023]      FIG. 13  is a plan view of the filled, sealed package shown in  FIG. 12  but after portions of the front, back and side gussets of that package have been die-cut along lines immediately outside of the top end seal line and discarded to complete the package in accordance with a method step shown in the flow diagram of  FIG. 4 ; 
           [0024]      FIG. 14  is a flow diagram showing the steps of another method of making a series of packages like shown in  FIGS. 1-3 ; 
           [0025]      FIG. 15  is a plan view of a portion of a web of flexible packaging material which has been slit into two web sections for forming a series of front and back panels for a series of packages in accordance with a method step shown in the flow diagram of  FIG. 14 ; 
           [0026]      FIG. 16  is a combined plan and isometric view of a portion of a web of flexible packaging material shown forming one tube of a plurality of tubes for use with the front and back panels shown of  FIG. 15  for producing a series of package in accordance with a method step shown in the flow diagram of  FIG. 14 ; 
           [0027]      FIG. 17  is a combined plan and isometric view of a portion of the web of flexible packaging material making up a series of sequentially located back panels on which a plurality of tubes like that shown in  FIG. 16  have been disposed, and a portion of the web of flexible packaging material making up a series of sequentially located front panels arranged for disposition over the web of back panels to produce a series of packages in accordance with a method step shown in the flow diagram of  FIG. 14 ; 
           [0028]      FIG. 18  is an isometric view of a portion of the web of sequentially located front panels disposed over the portion of the web of sequentially located back panels with the plural tubes interposed therebetween and tacked thereto to produce an assembly from which a series of packages are produced in accordance with a method step shown in the flow diagram of  FIG. 14 ; and 
           [0029]      FIG. 19  is a plan view of the assembly of  FIG. 18  but showing that assembly after the sequentially located sections forming the front and back panels and interposed tubes (which form the side gussets) have been sealed along respective seal lines in accordance with two method steps shown in the flow diagram of  FIG. 14 . 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
       [0030]    Referring now to the various figures of the drawing wherein like reference characters refer to like parts, there is shown at  20  in  FIG. 1  one exemplary embodiment of a side-gusseted package constructed in accordance with this invention. The package has a central longitudinal axis A and basically comprises a front panel  22 , a back or rear panel  24 , a first side gusset panel  26  and a second side gusset panel  28  which are fixedly secured, e.g., heat or ultrasonically sealed, to one another. In particular, as best seen in  FIGS. 1 and 2 , one side edge of the front panel  22  is fixedly secured to a front edge of the first side gusset panel  26  along a seal line  30  and another side edge of that front panel is fixedly secured to a front edge of the second side gusset panel  28  along a seal line  32 . The back panel  24  is of the same shape and size as the front panel  22 . One side edge of the back panel  24  is fixedly secured to a rear edge of the first side gusset panel  26  along a seal line  34  and another side edge of that back panel is fixedly secured to a rear edge of the second side gusset panel  28  along a seal line  36 . The front panel  22 , the back panel  24  and the lower edges of the two side gusset panels  26  and  28  are fixedly secured along a bottom seal line  38  ( FIG. 3 ), which is preferably linear. The front panel  22 , the back panel  24  and the upper edges of the two side gusset panels  26  and  28  are fixedly secured along a top seal line  40 . The top seal line is shown as being arcuate, but could if desired be of any other shape, e.g., linear, so long as it extends across the top of the package. 
         [0031]    As will be seen in the discussion to follow, when the package  20  is made, there will be a point where all of its side seals and its bottom seal will have been completed, to thereby create a hollow body having an open top. It is through that open top that the contents of the package, e.g., any product, such as coffee, etc., can be introduced. Once the package is filled with the product the top portion of the package is sealed to enclose the product within the package. 
         [0032]    In order to render the package suitable to be readily grasped by a user, the side seals lines  30 ,  32 ,  36  and  26  are not linear (as has characterized prior art side-gusseted packages), but rather are somewhat necked down at approximately their mid-portion. To that end, the seal line  30  includes a pair of end edge portions  30 A and an intermediate edge portion  30 B. The end edge portions  30 A are preferably linear (but may be arcuate), while the intermediate edge portion  30 B is preferably concave, e.g., an inwardly extending arcuate shape, but can be of other shapes. In a similar manner the seal line  32  includes a pair of linear end edge portions  32 A and a concave intermediate edge portion  32 B. Thus, the intermediate edge portions  30 B and  32 B of the two front panel side seals are located closer to the central axis A, than the end edge portions  30 A and  32 A of those seal lines. In a similar manner, the seal line  34  includes a pair of linear end edge portions  34 A and a concave intermediate edge portion  34 B, while the seal line  36  includes a pair of linear end edge portions  36 A and a concave intermediate edge portion  36 B. Thus the intermediate edge portions  34 B and  36 B of the two back panel side seals are located closer to the central axis A, than the end edge portions  34 A and  36 A of those seal lines. 
         [0033]    As best seen in  FIGS. 1 and 2  each of the gusseted side panels comprises pair of gusset sections connected to each other by a fold line. In particular, the gusset panel  26  includes a gusset section  26 A and a gusset section  26 B connected to each other by a fold line  26 C. In a similar manner the gusset panel  28  includes a gusset section  28 A and a gusset section  28 B connected to each other by a fold line  28 C. 
         [0034]    Turning now to  FIGS. 4-13 , one exemplary embodiment of a method of producing plural side-gusseted packages  20  will now be described. The entire method is depicted in the flow or block diagram of  FIG. 4  and in the corresponding  FIGS. 5-13 , showing the sequential steps in the process. To that end, a web of any suitable flexible packaging material, e.g., a laminate, is unwound from a supply of that material and is formed into a folded tube like shown in  FIGS. 5 and 5A . The tube includes a front face  122  (which will become the front panels  22  of the series of packages), a back face  124  (which will become the back panels  24  of the series of packages), a first gusseted side  126  (which will become the first side gusset panels  26  of the series of packages), and a gusseted side  128  (which will become the second side gusset panels  28  of the series of packages). 
         [0035]    Portions of the front face  122  are then sealed to the adjacent portions of the gusseted sides  126  and  128  along seal lines  130  and  132 , respectively, (which will become the seal lines  30  and  32  of the series of packages). At the same time portions of the back face  124  are sealed to the adjacent portions of the gusseted sides  126  and  128  along similar seal lines (not shown, and which will become the seal lines  34  and  36  of the series of packages). Once the seals are completed the sealed tube is die cut along die-cut lines  100 , which are immediately adjacent and outside of the side seal lines as shown in  FIG. 7 . The portions of the tube located outside of the seal line are designated by the reference number  102  and serve as the trim, so that they are discarded leaving the tube as shown in  FIG. 8 . A transverse seal  38 , which serves as the bottom seal line of the package, is then applied across the width of the tube at longitudinally spaced locations along the central longitudinal axis A as shown in  FIG. 9 . The spacing between the transverse seal lines effectively establishes a series of sequentially located tube sections, each of which is the precursor to the formation of a respective package  20 . The tube is then die-cut along a line immediately below each transverse seal line as shown in  FIG. 10 . This results in a hollow body  20 ′, like shown in  FIG. 11 . The top portion  20 A of the hollow body  20 ′ is open, i.e., unsealed at this time, so that it serves as a mouth through which a product (not shown) can be introduced into the hollow interior of the body. Once the body  20 ′ is filled, the top portion is sealed by the top seal line  40  (which extends transversely across the body) to enclose the product within the body as shown in  FIG. 12 . Once the product is sealed within the body, the portions of the body immediately above the top seal line are die-cut and discarded as trim, resulting in a completed package  20 , such as shown in  FIG. 13 . 
         [0036]    Turning now to  FIGS. 14-22 , another exemplary embodiment of a method of producing plural side-gusseted packages  20  will now be described. The entire method is depicted in the flow or block diagram of  FIG. 14  and in the corresponding  FIGS. 15-19  and  11 - 13 , showing the sequential steps in the process. To that end, a web of any suitable flexible packaging material  10 , e.g., a laminate, is unwound from a supply of that material and is slit longitudinally in half along line  10 A as shown in  FIG. 15  to result in two web sections  222  and  224 . Each of these sections is the precursor of a series of front and back panels to form a series of packages  20 , thus the sections  222  and  224  of indeterminate length. Another web of any suitable flexible packaging material  10 , e.g., a laminate, is unwound from a supply of that material and as shown in  FIG. 16  is formed into a plurality of tubes  226  and  228 . These tubes serve as precursors of the side gusset panels  26  and  28  of the package. As can be seen in  FIG. 16  an adhesive strip  200 , e.g., tape, is unwound from a supply reel and applied to the outer surface of the tubes  226 / 228  along the abutting longitudinal marginal edges of those tubes to hold the tubes together. The tubes are then disposed on the back web section  224  at spaced locations therealong and are tacked thereon to hold the tubes in place as shown in  FIG. 17 . The front web section  222  is then juxtaposed over the back rear section and is tacked in place thereon to result in an assembly like shown in  FIG. 18 . 
         [0037]    The assembly of  FIG. 18  is then sealed along plural seal lines  130 ,  132  to join the front web section to the underlying portions of the gusset sections (the contiguous portions of the tubes  226  and  228 ). At the same time plural seal lines (not shown) are produced joining the back web section to the overlying portions of the gusset sections (the contiguous portions of the tubes  226  and  228 ). These seal lines are the precursors of the side seals  30 ,  32 ,  34  and  36  of the package. After the precursors of the side seal lines are produced a seal line  128  extending along one side of the assembly is formed. The seal line  128  is the precursor of the bottom seal  38  of the package. 
         [0038]    After the bottom seal line  128  has been made, the sequentially located sections of the assembly are die-cut from each other to result in a body like shown in previously described  FIG. 11 . The top portion  20 A of the hollow body  20 ′ is open, i.e., unsealed at this time, so that it serves as a mouth through which a product (not shown) can be introduced into the hollow interior of the body. Once the body  20 ′ is filled the top portion is sealed by the top seal line  40  (which extends transversely across the body) to enclose the product within the body as shown in previously described  FIG. 12 . Once the product is sealed within the body, the portions of the body immediately above the top seal line are die-cut and discarded as trim, resulting in a completed package  20 , such as shown in previously described  FIG. 13 . 
         [0039]    It should be pointed out at this juncture that this invention contemplates a variety sizes and shapes of side-gusseted packages which are configured to enable ready manual handling. The packages of this invention can be used to hold any type of product and may, if desired, include a one-way valve (not shown). Such valves are commonly used in flexible packaging holding coffee to enable the coffee to degas through the valve, while preventing the ingress of air into the package. 
         [0040]    Without further elaboration the foregoing will so fully illustrate my invention that others may, by applying current or future knowledge, adopt the same for use under various conditions of service.