Abstract:
The present invention is a collapsible liner for use in a bulk container. The liner comprises a first flexible panel, a second flexible panel, a first seal, a second seal, and a tab. The first flexible panel includes a first longitudinal edge. The second flexible panel includes a second longitudinal edge. The first seal joins the first and second panels near the first and second longitudinal edges and runs generally parallel to the first and second edges. The second seal joins the first and second panels and is generally oblique to the first seal. At least one of the panels extends across at least one of the seals to form the tab, which includes an attachment feature. The attachment feature may be a piece of tape affixed to the tab. The attachment feature may be a strip of fabric or other reinforcement material melted into the tab, sealed within the tab or affixed to the tab via an adhesive. The attachment feature may be a hole with sealed or unsealed edges. The attachment feature may be a grommet or a loop for receiving a hook.

Description:
FIELD OF THE INVENTION 
       [0001]    The present invention relates to flexible liners for use in bulk containers such as those used in flexible intermediate bulk container (“FIBC”) systems or bag-in-box container systems. More particularly, the present invention relates to systems and methods for securing a flexible liner within a container used in a FIBC or bag-in-box container system. The present invention also relates to systems and methods of draining flexible liners used in FIBC or bag-in-box container systems. 
       BACKGROUND OF THE INVENTION 
       [0002]    In recent years a number of industries have adopted the FIBC or bag-in-box concept for storing and transporting liquid and particulate commodities in relatively large quantities. For example, the FIBC or bag-in-box concept has been employed for transporting in bulk such diverse products as vegetable oils, salad dressings, syrups, soy sauce, peanut butter, pharmaceuticals, talc, motor oil, industrial chemicals, detergents in liquid or powder form, and toiletry products or ingredients. 
         [0003]    The FIBC concept is a bulk container system comprising a flexible liner in a flexible or semi-flexible bag. In one embodiment, a FIBC bag is made of a woven material (e.g., woven polymer, TYVEX®, canvas, wire mesh or net). The flexible liner is typically chemically resistant and impermeable to water and air and serves as the container for a selected commodity. The FIBC bag serves as a protective container for the liner and its contents. A FIBC bag is disclosed in U.S. Pat. No. 4,596,040 to LaFleur et al., which issued Jun. 17, 1986 and is hereby incorporated by reference in its entirety. 
         [0004]    The bag-in-box concept comprises a flexible liner and a rigid or semi-rigid box. The flexible liner is typically chemically resistant and impermeable to water and air and serves as the container for a selected commodity. The box may be made of plywood or other wood materials, cardboard, fiberboard, metal or plastic. The box serves as a protective container for the liner and its contents. A box for a bag-in-box system is disclosed in U.S. Pat. No. 6,533,122 to Plunkett, which issued Mar. 18, 2003 and is hereby incorporated by reference in its entirety. A bag for use in a bag-in-box system is disclosed in U.S. patent application Ser. No. 10/818,882, which was filed Apr. 6, 2004, is entitled “Bag With Flap For Bag-In-Box Container System” and is hereby incorporated by reference in its entirety. 
         [0005]    By way of example, a liner used for shipping commodities in bulk, via a FIBC or bag-in-box system, typically may have a volume in the order of 60 cubic feet. In one embodiment, the liner will include at least a drain fitting near the bottom of the liner whereby the liner&#39;s contents may be removed. In other embodiments, the liner will include at least a filler fitting near the top of the liner whereby the liner may be filled with its contents. In other embodiments, the liner will include both a filler fitting near the top of the liner and a drain fitting near the bottom of the liner. 
         [0006]    In embodiments of the liner with at least a drain fitting, the outer container (i.e., the bag of a FIBC system or the box of a bag-in-box system) is provided with a discharge opening near or at the bottom end of the outer container through which the liquid or particulate contents can be discharged from the liner via its drain fitting. The discharge opening of the outer container may be fitted with a drain fitting that mates with or accommodates the drain fitting of the liner. This mating arrangement between drain fittings of the liner and outer container assures that material discharged from the liner will be directed to the intended receiving facility and prevents the material from accumulating in the bottom of the outer container. 
         [0007]    In embodiments of the liner with at least a filler fitting, the outer container usually comprises a cover or top panel that is removable to permit access to the liner and the filler fitting. 
         [0008]    An important financial consideration of the FIBC or bag-in-box mode of shipment of materials in bulk is that the outer container can be a non-returnable or one-way container. For example, where the outer container is a box for a bag-in-box system and is generally made of a corrugated fiberboard or the like, the box can be discarded after use. Alternatively, the box may consist of interlocking panels of metal, wood or a stiff or rigid plastic material, in which case the box may be disassembled and returned to the shipper after the associated liner has been emptied of its contents. 
         [0009]    Where the outer container is a bag for a FISC system and is made of a low cost woven material, the bag can be discarded after use. Alternatively, where the material of the bag is more expensive, the bag may be collapsed and returned to the shipper after the associated liner has been emptied of its contents. 
         [0010]    With respect to the FIBC and bag-in-box concepts as applied to bulk shipment of commodities, the plastic flexible liners have taken various forms. One common form is the so-called “pillow” type, which consists of at least two sheets of plastic film sealed together at their edges. Another common form is the six-sided flexible liners (e.g., liners that take the shape of a cube or rectangular parallelepiped when filled) made from a plurality of sheets of plastic film. 
         [0011]    Regardless of the type of liner in the outer container, if the liner is large (e.g., a liner having a volume of about 275 gallons or more), it can be difficult to completely fill or empty the liner. This is especially the case when the content of the liner is a viscous liquid. During the discharge of the liner&#39;s contents, the evacuated portion of the liner has a tendency to collapse due to a vacuum affect. Similarly, when the liner is being filled, the liner again tends to collapse because the contents pull the sides of the liner downward. In either case, as the liner collapses, folds are created that entrap the contents of the liner. 
         [0012]    During emptying of a large liner, the emptying process can still be difficult and incomplete even if liner collapse is minimal. This is because the liner bottom typically does not slope towards the drain fitting. Consequently, the contents of the liner can tend to pool in the bottom of the liner. 
         [0013]    There is a need in the art for a system and method of supporting a liner off of an outer container used in a FISC or bag-in-box system, thereby decreasing the tendency of the liner to collapse during filling or emptying of the liner. There is also a need in the art for a system and method of causing a liner bottom to slope towards the drain fitting of the liner. 
       BRIEF SUMMARY OF THE INVENTION 
       [0014]    The present invention, in one embodiment, is a collapsible liner for use in a bulk container. The liner comprises a first flexible panel, a second flexible panel, a first seal, a second seal, and a tab. The first flexible panel includes a first longitudinal edge. The second flexible panel includes a second longitudinal edge. The first seal joins the first and second panels near the first and second longitudinal edges and runs generally parallel to the first and second edges. The second seal joins the first and second panels and is generally oblique to the first seal. At least one of the panels extends across at least one of the seals to form the tab, which includes an attachment feature adapted to facilitate the attachment of the tab to the bulk container. 
         [0015]    The present invention, in another embodiment, is a collapsible liner for use in a bulk container. The liner comprises first, second and third flexible panels, first, second, third, fourth and fifth seals, and a tab. The first flexible panel includes a first longitudinal edge and a first lateral edge generally perpendicular to the first longitudinal edge. The second flexible panel includes a second longitudinal edge and a second lateral edge generally perpendicular to the second longitudinal edge. The third flexible panel includes a third longitudinal edge, a fourth longitudinal edge generally parallel to the third longitudinal edge, and a third lateral edge generally perpendicular to the third longitudinal edge. 
         [0016]    The first seal joins the first and third panels near the first and third longitudinal edges and runs generally parallel to the first and third edges. The second seal joins the second and third panels near the second and fourth longitudinal edges and runs generally parallel to the second and fourth edges. The third seal joins the first and third panels and is generally oblique to the first seal. 
         [0017]    The fourth seal joins the second and third panels and is generally oblique to the second seal. The fifth seal joins the first and second panels near the first and second lateral edges and runs generally perpendicular to the first and second longitudinal edges. 
         [0018]    The first panel extends across the third seal to the fifth seal. The second panel extends across the fourth seal to the fifth seal. The tab is defined in the first panel between the third and fifth seals. The tab includes an attachment feature adapted to facilitate the attachment of the tab to the bulk container. 
         [0019]    The present invention, in another embodiment, is a liner for use in a bulk container. The liner comprises a first flexible panel and a tab. The tab is defined in a portion of the first panel and includes a piece of tape affixed to the tab. 
         [0020]    The present invention, in another embodiment, is a liner for use in a bulk container. The liner comprises a first flexible panel and a tab defined in a portion of said first panel. The tab includes a piece of fabric or other reinforcement material. In one embodiment, the fabric or other material is affixed to the tab via an adhesive. In other embodiments, the fabric or other material is melted into the tab or sealed within a tab. 
         [0021]    The present invention, in another embodiment, is a liner for use in a bulk container. The liner comprises a first flexible panel joined to a second flexible panel by a first seal and a second seal oblique to the first seal. The first and second seals form an intersection. At least one of the panels extends across at least one of the seals to form an elongated tab adapted for connection to the bulk container. In one embodiment, the elongated tab is sufficiently long to facilitate its attachment and use with a winder. In one embodiment, the elongated tab is configured such that its length, from a free distal end of the tab to the intersection, is approximately two times or greater the width of the tab. In one embodiment, the elongated tab is configured such that its length is approximately three times or greater the width of the tab. In one embodiment, the elongated tab is configured such that its length is approximately four times or greater the width of the tab. 
         [0022]    The present invention, in another embodiment, is a method of attaching a liner to a bulk container where the liner comprises a first flexible panel and an elongated tab defined in a portion of said first panel. In one embodiment the tab further comprises an attachment feature adapted to facilitate the attachment of the tab to the bulk container. The method comprises extending the tab from the liner to a surface of the bulk container and affixing the tab to the surface of the bulk container. In one embodiment, attachment feature is a strip of tape and the tab is affixed to the surface of the bulk container via an adhesive on the tape. In another embodiment, whether the attachment feature is a strip of tape or a piece of fabric or reinforcement material, the tab is affixed to the surface of the bulk container by stitching through the tape or fabric, the tab and into the surface of the bulk container. 
         [0023]    The present invention, in another embodiment, is a liner for use in a bulk container. The liner comprises first, second, third and fourth flexible panels, first and second pairs of oblique seals, a cross seal, and first and second pairs of side seals. 
         [0024]    The first flexible panel and the second flexible panel are opposed to each other. Each of the first and second panels includes a pair of side edges. The third flexible panel and the fourth flexible panel are opposed to each other and are located between the first and second panels. Each of the third and fourth panels includes a pair of side edges. 
         [0025]    The first pair of oblique seals joins the first panel to the third and fourth panels. Each oblique seal of the first pair of oblique seals runs along the first panel generally oblique to the side edges of the first panel. The oblique seals of the first pair of oblique seals converge towards each other to define a first truncated apex. Each oblique seal of the first pair of oblique seals has a portion near the first apex that transitions through a radius to a segment generally parallel to the side edges of the first panel. 
         [0026]    The second pair of oblique seals joins the second panel to the third and fourth panels. Each oblique seal of the second pair of oblique seals runs along the second panel generally oblique to the side edges of the second panel. The oblique seals of the second pair of oblique seals converge towards each other to define a second truncated apex. Each oblique seal of the second pair of oblique seals has a portion near the first apex that transitions through a radius to a segment generally parallel to the side edges of the first panel. 
         [0027]    The cross seal joins the first panel to the second panel at the truncated apexes of the first and second panels. More specifically, in one embodiment, the cross seal perpendicularly intersects the segments of the seals of the first and second pairs of oblique seals. 
         [0028]    The first pair of side seals runs generally parallel to the side edges of the first panel and joins the third and fourth panels to the first panel. In one embodiment, each side seal of the first pair of side seals intersects an end of an oblique seal of the first pair of oblique seals opposite the first apex. 
         [0029]    The second pair of side seals runs generally parallel to the side edges of the second panel and joins the third and fourth panels to the second panel. In one embodiment, each side seal of the second pair of side seals intersects an end of an oblique seal of the second pair of oblique seals opposite the second apex. 
         [0030]    In one embodiment, the first and second apexes converge to form an end wall of the liner. In one embodiment, the first and second pairs of oblique seals define apexes in the third and fourth panels that are generally non-truncated, or in other words, generally pointed. These apexes in the third and forth panels also join with the apexes in the first and second panels to form an end wall of the liner. 
         [0031]    The present invention, in another embodiment, is a liner for use in a bulk container. The liner comprises a first flexible side panel, a second flexible side panel, a seal, a top flap and a tab. The second flexible side panel forms a side edge of the container. The seal joins the first flexible side panel to the second flexible side panel and runs generally oblique to the side edge. The top flap is defined in at least one of the flexible side panels between the seal and a top edge of the at least one flexible side panel. The tab defined in the top flap. 
         [0032]    In one embodiment, the tab comprises substantially all of the top flap. In one embodiment, the tab is a rectangular portion of the top flap. In one embodiment, the tab is a triangular portion of the top flap. 
         [0033]    In one embodiment, the liner further comprises a L-shaped generally continuous cut or series of perforations in the top flap that define a generally rectangular tab. In another embodiment, the liner further comprises a generally continuous cut or series of perforations in the top flap that run generally parallel to at least a portion of the seal and define a tab that is generally triangular and comprises substantially all of the top flap. 
         [0034]    While multiple embodiments are disclosed, still other embodiments of the present invention will become apparent to those skilled in the art from the following detailed description, which shows and describes illustrative embodiments of the invention. As will be realized, the invention is capable of modifications in various aspects, all without departing from the spirit and scope of the present invention. Accordingly, the drawings and detailed description are to be regarded as illustrative in nature and not restrictive. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0035]      FIG. 1  is a top isometric view of a liner in its inflated or filled state; 
           [0036]      FIG. 2  is a plan view of the liner in a flattened as-made condition, with a part of the liner broken away; 
           [0037]      FIG. 3  is a bottom view of the same liner in its flattened as-made condition, with a part of the liner broken away; 
           [0038]      FIG. 4  is a cross sectional view taken along line  4 - 4  of  FIG. 2 ; 
           [0039]      FIG. 5 a    is a top isometric view of the upper portion of the liner in its inflated or filled state with the tabs detached in preparation for engagement with an outer container; 
           [0040]      FIG. 5 b    is a vertical sectional view taken along section line  5   b - 5   b  of  FIG. 5 a    of a tab affixed to the surface of an outer container; 
           [0041]      FIG. 6  is a cross sectional view of fill fitment taken along line  6 - 6  of  FIG. 2 ; 
           [0042]      FIG. 7  is a top isometric view of the upper portion of the liner in its inflated or filled state with an alternative embodiment of the tabs; 
           [0043]      FIG. 8  is a bottom view of the upper portion of the liner depicted in  FIG. 7  in its flattened as-made condition, with a part of the liner broken away; 
           [0044]      FIG. 9  is a top isometric view of the upper portion of the liner in its inflated or filled state with an open neck top and an alternative embodiment of the tabs; 
           [0045]      FIG. 10  is a bottom view of the upper portion of the liner depicted in  FIG. 9  in its flattened as-made condition, with a part of the liner broken away. In the several figures like numerals designate like elements. 
           [0046]      FIG. 11  is a side elevation of a liner attached to a winder system to facilitate the complete emptying of the liner. 
       
    
    
     DETAILED DESCRIPTION 
       [0047]    The present invention is directed to a flexible liner  1  for use in bulk containers such as those used in flexible intermediate bulk container (“FIBC”) systems or bag-in-box container systems. Generally speaking, in one embodiment, the flexible liner  1  of the present invention has integrally formed tabs  2  that are partially separable from the liner  1  for connection to an outer container (i.e., the bag of a FIBC system or the box of a bag-in-box system) and/or use in a winder system that can be used to facilitate the emptying of the liner  1 . 
         [0048]      FIG. 1  is a top isometric view of the liner  1  in its inflated or filled state. As illustrated in  FIG. 1 , in one embodiment, the tabs  2  are located near the top portion of the liner  1  and are provided with an attachment feature  3  for securing the tabs  2  to the outer container. Depending on the embodiment, the attachment feature  3  may be a strip of tape, a strip of fabric or another reinforcing material, or a hole through the tab  2 . In one embodiment, the tab  2  is not provided with a special attachment feature, but is simply the tab  2 . 
         [0049]    Once the tabs  2  are affixed to the outer container (whether an attachment feature is employed or not), the tabs  2  support the liner  1  off of the outer container, thereby reducing the degree to which the liner  1  collapses when being filled or emptied. Additionally, when the liner  1  is being emptied, the tabs  2  may be detached from the outer container and connected to a winder system. The tabs  2  are then wound about the winder, which causes the contents of the liner  1  to flow towards the drain fitting  50  of the liner  1 . 
         [0050]    As indicated in  FIG. 1 , in one embodiment, the liner  1  is a four side-seal type liner  1  (i.e., a liner having four longitudinal side-seals  23 ,  24 ,  25 ,  26 ) composed of four discrete portions (i.e., a front portion  4 , a rear portion  6  and two side portions  8 ,  10 ) of flexible, heat-sealable packaging material in sheet form. By way of example but not limitation, the packaging sheet material may consist of polyethylene or polypropylene or some other thermoplastic material or be a laminate of two or more packaging materials bonded to one another. Each of the portions  4 - 10  may comprise a single sheet of packaging material (“single ply”) or two or more sheets of packaging material (“multi-ply”). In the case of multi-ply portions, the individual sheets (“plies”) may be of like or different material and are secured to one another only in selected areas (e.g., at seals  23 ,  24 ,  25 ,  26  and other such seals as discussed in this detailed description). The preferred embodiment is a two-ply liner. 
         [0051]    For convenience and simplicity of illustration, the two-ply construction is evidenced only in  FIGS. 4 and 6 , with the two plies of the front portion  4 , for example, being identified as  4 A and  4 B. However, in the following description, it is to be assumed and understood that each of the four discrete portions  4 - 10  of the liner  1  consists of two plies of flexible packaging material. 
         [0052]    For a discussion of the liner  1  in its flat as-formed condition, reference is now made to  FIGS. 2-4 .  FIG. 2  is a plan view of the liner  1  in its flattened as-made condition, with part of the front portion  4  broken away to reveal the side portions  8 ,  10  below.  FIG. 3  is a bottom view of the liner  1  in its flattened as-made condition, with part of the rear portion  6  broken away to reveal the side portions  8 ,  10  above.  FIG. 4  is a cross sectional view of the liner  1  taken along line  4 - 4  of  FIG. 2 . As shown in  FIGS. 2-4 , the front portion  4  and the rear portion  6  are opposed to one another, and the side portions  8 ,  10  are interposed between the front portion  4  and the rear portion  6 . As best illustrated in  FIG. 4 , the side portions  8 ,  10  are folded inwardly on themselves to form gussets consisting of folds  13 ,  14  and  15 ,  16 , respectively. 
         [0053]    As indicated in  FIGS. 2 and 3 , when the liner  1  is in the flattened as-made condition, the front portion  4  and the rear portion  6  have a generally rectangular configuration defined by a top edge  18 , a bottom edge  20 , and two side edges  21 ,  22 . During manufacture, the four portions  4 - 10  are cut from parallel elongate supply webs of packaging material. The four portions  4 - 10  are substantially the same width (i.e., the distance between the side edges  21   a ,  22   a with respect to portion  4 , the distance between the side edges  21   c,    22   c  with respect to portion  6 , the distance between the side edges  21   b ,  21   d  with respect to portion  8 , and the distance between the side edges  22   b,    22   d  with respect to portion  10 ) as the webs from which they are separated. The side portions  8 ,  10  are folded and inserted between the front portion  4  and the rear portion  6  before the four portions  4 - 10  are cut from the supply webs. As used herein and where the context so admits, the term “web” is to be understood as consisting of a single continuous sheet or two or more sheets that are brought together to form a multiply portion of a liner. Alternatively, as used herein, the term “web” is to be understood as consisting of a tubular film that is equivalent to two sheets that are brought together to form a multiply portion of a liner. 
         [0054]    As shown in  FIGS. 2 and 4 , the front portion  4  is sealed via longitudinal seal lines  23 ,  24  along its two longitudinally extending side edges  21   a ,  22   a  to the adjacent side edges  21   b ,  22   b  of the folds  13 ,  15  of the respective side portions  8 ,  10 . As indicated in  FIGS. 3 and 4 , the rear portion  6  is sealed via longitudinal seal lines  25 ,  26  along its two longitudinally extending side edges  21   c,    22   c  to the adjacent side edges  21   d,    22   d  of the folds  14 ,  16  of the respective side portions  8 ,  10 . 
         [0055]    As illustrated in  FIGS. 2 and 3 , adjacent the top end of the liner  1 , two oblique seals  27 ,  28  secure the front portion  4  to the folds  13 ,  15 , and another two oblique seals  29 ,  30  secure the rear portion  6  to the folds  14 ,  16 . Adjacent the bottom end of the liner  1 , two oblique seals  31 ,  32  secure the front portion  4  to the folds  13 ,  15 , and another two oblique seals  33 ,  34  secure the rear portion  6  to the folds  14 ,  16 . 
         [0056]    As shown in  FIGS. 2 and 3 , in one embodiment, the oblique seals  27 ,  28 ,  31 ,  32  extend through the longitudinal seals  23 ,  24 , while the other oblique seals  29 ,  30 ,  33 ,  34  extend through the other longitudinal seals  25 ,  26 . In other embodiments, the oblique seals  27 - 34  stop at their respective intersections with the longitudinal seals  23 - 26 . 
         [0057]    In one embodiment, at the top end of the liner  1 , a cross seal  40  extends laterally across the front and rear portions  4 ,  6  adjacent and parallel to the top edge  18 . The top cross seal  40  seals the front and rear portions  4 ,  6  together along the length of the top cross seal  40 . The top oblique seals  27 - 30  extend from their intersections with their respective longitudinal seals  23 - 26  towards the top cross seal  40 . Just prior to intersecting the top cross seal  40 , each top oblique seal  27 - 30  curves from an oblique orientation to an orientation that is generally parallel to the longitudinal seals  23 - 26 , thereby forming a short segment  44  with a curve  45  for each oblique seal  27 - 30  that extends through the top cross seal  40 . 
         [0058]    As shown in  FIGS. 2 and 3 , at the bottom end of the liner  1 , a cross seal  42  extends laterally across the front and rear portions  4 ,  6  adjacent and parallel to the bottom edge  20 . The bottom cross seal  42  seals the front and rear portions  4 ,  6  together along the length of the bottom cross seal  42 . The bottom oblique seals  31 - 34  extend from their intersections with their respective longitudinal seals  23 - 26  towards the bottom cross seal  42 . Just prior to intersecting the bottom cross seal  42 , each bottom oblique seal  31 - 34  curves from an oblique orientation to an orientation that is generally parallel to the longitudinal seals  23 - 26 , thereby forming a short segment  46  with a curve  47  for each oblique seal  31 - 34  that extends through the bottom cross seal  42 . 
         [0059]    In manufacturing the liner  1 , the cross seals  40 ,  42  may require a greater temperature/pressure as compared to those used to make the longitudinal side seals  23 - 26  and the oblique seals  27 - 34 . This is because, in one embodiment, the cross seals  40 ,  42  utilize twice as many layers as the side and oblique seals  23 - 34 . For example, referring to the upper right hand corner of  FIG. 2 , oblique seal  28  and longitudinal side seal  24  are each formed by sealing front portion  4  and side portion  10  together. In contrast, cross seal  40  is formed by sealing together front portion  4 , rear portion  6 , and portion  10  folded over on itself (i.e., two layers of portion  10  are sealed together with the front and rear portions  4 ,  6 ). 
         [0060]    As illustrated in  FIGS. 2 and 3 , the front and rear portions  4 ,  6  each have a generally hexagonal configuration (as defined by their respective longitudinal side seals  23 - 26  and oblique seals  27 - 34 ), except for being truncated at the upper most point by the top cross seal  40  and at the bottom most point by the bottom cross seal  42 . As can be understood from  FIG. 1 , the side portions  8 ,  10  also each have a generally hexagonal configuration (as defined by their respective longitudinal side seals  23 - 26  and oblique seals  27 - 34 ) when fully spread out flat. However, as can be understood from  FIG. 1 , unlike the front and rear portions  4 ,  6 , the upper and lower most points of the side portions  8 ,  10  are not truncated. 
         [0061]    As can be understood from  FIG. 1 , the curves  45 ,  47  and the truncated top and bottom end points of the hexagonal front and rear portions  4 ,  6  form intersections between the panels  4 - 10  that are advantageous over standard non-truncated intersections found in the prior art. This is because the truncated end points and the curves  45 ,  47  reduce stress concentrations in the intersection areas as compared to the non-truncated intersections found in the prior art. 
         [0062]    In one embodiment, the curves  45 ,  47  have a radius of between approximately 0.5″ to approximately 4.0″. In another embodiment, the curves  45 ,  47  have a radius of between approximately 1.0″ to approximately 3.0″. In one embodiment, the radius is approximately 2.0″. 
         [0063]    As can be understood from  FIGS. 1-3 , the hexagonal configuration of each portion  4 - 10  can be divided into three parts, which are a top triangular section  4   x,    6   x,    8   x,    10   x,  a rectangular section  4   y,    6   y,    8   y,    10   y,  and a bottom triangular section  4   z,    6   z,    8   z,    10   z.  The top triangular sections  4   x,    6   x,    8   x,    10   x  are defined by the top oblique seals  27 - 30  and top fold lines  66  that run parallel to the top cross seal  40  and intersect the intersections between the top oblique seals  27 - 30  and the longitudinal side seals  23 - 26 . Similarly, the bottom triangular sections  4   z,    6   z,    8   z,    10   z  are defined by the bottom oblique seals  31 - 34  and bottom fold lines  68  that run parallel to the bottom cross seal  42  and intersect the intersections between the bottom oblique seals  31 - 34  and the longitudinal side seals  23 - 26 . The rectangular sections  4   y,    6   y,    8   y,    10   y  are defined by the longitudinal side seals  23 - 26  and the top and bottom fold lines  66 ,  68 . 
         [0064]    As can be understood from  FIG. 1 , when the liner  1  is inflated or filled, the top triangular sections  4   x,    6   x,    8   x,    10   x  fold toward each other about their respective top fold lines  66  to form the roof of the cubical liner  1 , the bottom triangular sections  4   z,    6   z,    8   z,    10   z  fold toward each other about their respective bottom fold lines  68  to form the floor of the cubical liner  1 , and the rectangular sections  4   y,    6   y,    8   y,    10   y  fold about their respective longitudinal side seals  23 - 26  to form the sidewalls of the cubical liner  1 . 
         [0065]    As indicated in  FIG. 2 , the top oblique seals  27 ,  28 , the top cross seal  40 , and the side seals  23 ,  24  generally define front top flaps  4   a,    4   b  out of the front portion  4 . In one embodiment, each front top flap  4   a,    4   b  will further include corresponding areas of the side portions  8 ,  10  that are defined by the top oblique seals  27 ,  28 , the top cross seal  40 , and the side seals  23 ,  24 . 
         [0066]    As shown in  FIG. 3 , the top oblique seals  29 ,  30 , the top cross seal  40 , and the side seals  25 ,  26  generally define rear top flaps  6   a,    6   b  out of the rear portion  6 . In one embodiment, each rear top flap  6   a,    6   b  will further include corresponding areas of the side portions  8 ,  10  that are defined by the top oblique seals  29 ,  30 , the top cross seal  40 , and the side seals  25 ,  26 . 
         [0067]    As illustrated in  FIG. 1 , because the front top flaps  4   a,    4   b  are sealed to the rear top flaps  6   a,    6   b  by the top cross seal  40 , when the liner  1  is inflated or filled and takes its cubical form, the top flaps  4   a,    6   a  extend across the top triangular section  8   x  and the top flaps  4   b,    6   b  extend across the top triangular section  10   x.    
         [0068]    As indicated in  FIGS. 2 and 3 , in one embodiment, each longitudinal side seal  23 - 26  has a segment that extends across the respective top oblique seal  27 - 30  and into the respective top flap  4   a,    4   b,    6   a,    6   b.  In one embodiment, as shown in  FIGS. 2 and 3 , these top segments  23   a,    24   a,    25   a,    26   a  run from the intersection of the respective oblique seal  27 - 30  and side seal  23 - 26  to a point approximately halfway to the top cross seal  40 . In other embodiments, the top segments  23   a,    24   a,    25   a,    26   a  will have a greater or lesser length. In one embodiment, each longitudinal side seal  23 - 26  stops at its intersection with the respective top oblique seal  27 - 30  such that there are no top segments  23   a,    24   a ,  25   a,    26   a.    
         [0069]    As illustrated in  FIGS. 2 and 3 , in one embodiment, each top flap  4   a,    4   b,    6   a,    6   b  has a tab  2 , which has a generally rectangular shape defined by an edge  21 ,  22  of the respective top flap  4   a,    4   b,    6   a,    6   b  and an L-shaped perforated boarder  70 . In other embodiments, the perforated boarder  70  will define tabs  2  with other shapes (e.g., circular, triangular, etc.). 
         [0070]    As shown in  FIGS. 2 and 3 , the short segment of the L-shaped perforated boarder  70  is adjacent and generally parallel to the top cross seal  40 . 
         [0071]    The short segment of the L-shaped perforated boarder  70  forms the free distal end of a tab  2 . The long segment of the L-shaped perforated boarder  70  is generally parallel to its respective edge  21 ,  22  and extends from its intersection with the short segment to a point near its respective top oblique seal  27 - 30 . In one embodiment, each tab  2  has a length that is approximately 2″ to approximately 24″. In another embodiment, each tab  2  has a length that is approximately 6″ to approximately 24″. In another embodiment, each tab  2  has a length that is approximately 17″ to approximately 21″ long. In another embodiment, each tab  2  has a length that is approximately 2″ to approximately the distance between the top cross seal  40  and the intersections between the oblique seals  27 - 30  and the longitudinal side seals  23 - 26 . 
         [0072]    In one embodiment, the tabs  2  are of an elongated configuration such that they are sufficiently long to facilitate their attachment and use with a winder as discussed later in this Detailed Description. For example, in one embodiment, the tab  2  is configured such that its length (i.e., the distance from the free distal end of the tab to the intersection between the applicable longitudinal side seal  23 - 26  and oblique seal  27 - 30 ) is approximately two times or greater the width of the tab  2 . In another embodiment, the tab  2  is configured such that its length is approximately three times or greater the width of the tab  2 . In another embodiment, the tab  2  has a length that is approximately four times or greater the width of the tab  2 . In another embodiment, the tab  2  has a length that is approximately five times or greater the width of the tab  2 . In another embodiment, the tab  2  has a length that is approximately six times or greater the width of the tab  2 . 
         [0073]    As indicated in  FIGS. 2 and 3 , in one embodiment, each tab  2  has a top segment  23   a,    24   a,    25   a,    26   a  that extends along at least a portion of the tab  2  to reinforce the tab  2  by sealing its layers of the respective portion  4 - 10  together. In another embodiment, no segments  23   a,    24   a,    25   a,    26   a  exist because the longitudinal seal lines  23 - 26  terminate at their intersections with the oblique seals  27 - 30 . 
         [0074]    In other embodiments, the tabs  2  may be shapes other than rectangular and may be defined by perforated lines  70  that have configurations other than an L-shape. For example, a tab  2  may be any shape (e.g., rectangular, triangular, circular, elliptical, etc.) defined in a top flap  4   a,    4   b,    6   a,    6   b  by one or more perforated lines  70  or a combination of one or more perforated lines  70  and a longitudinal side edge  21 ,  22 . Also, the perforated lines  70  corresponding to such shapes may be straight, curved, segmented or otherwise configured to define such shapes. 
         [0075]    In one embodiment, a tab  2  may any portion of its respective top flap  4   a,    4   b,    6   a,    6   b.  For example, where a tab  2  comprises essentially all of its respective top flap  4   a,    4   b,    6   a,    6   b,  the perforated lines  70  may run adjacent to the oblique seals  27 - 30  from the top edge  18  to a point near the intersections between the oblique seals  27 - 30  and the longitudinal side seals  23 - 26  such that each tab  2  ends up being all or substantially all of its respective triangular shaped top flap  4   a ,  4   b,    6   a,    6   b.  In other words, such a tab  2  would be substantially all of a triangular area defined by a longitudinal side edge  21 ,  22 , a top edge  18  and a perforated line  70  running generally parallel and adjacent to an oblique seal  27 - 30 . 
         [0076]    As shown in  FIGS. 2 and 3 , in one embodiment, an attachment feature  3  exists on each tab  2 . In another embodiment, no attachment feature  3  exists on the tabs  2 . 
         [0077]    In one embodiment the attachment feature  3  is a strip of tape  3  that is affixed to each tab  2 . In one embodiment, the tape  3  has two adhesive sides, one adhesive side for adhering to the tab  2  and the other adhesive side for securing the tab  2  to an outer container (i.e., the bag of a FIBC system or the box of a bag-in-box system). In another embodiment, the tape  3  has a single adhesive side for adhering to the tab  2 . The tape  3  then acts as reinforcement for the tab  2 , thereby allowing the tab  2  to be stitched to the outer container without tearing free. 
         [0078]    In one embodiment, the attachment feature  3  is a strip of fabric  3  such as canvas, TYVEX®, or another reinforcing material. The strip of fabric  3  is affixed to the tab  2  via an adhesive or stitching, by being pressed into a tab  2  when the tab  2  is heated to its melting point, or by being sealed between the layers forming a tab  2 . The tabs  2  are then affixed to the top portion of the outer container by stitching through the fabric  3  and into the outer container. 
         [0079]    In one embodiment, the attachment feature  3  is one or more holes  3 . The one or more holes  3  may be any size and any shape, for example circular, elliptical, rectangular, etc. The holes may be reinforced with a grommet or by sealing together the layers comprising the tab  2  at or near the boarder of the hole  3 . Alternatively, the holes  3  may be formed without reinforcement. The tabs  2  are affixed to the top portion of the outer container by stitching through the one or more holes  3  and into the outer container. Alternatively, the one or more holes  3  may be tied to the outer container or attached to a hook extending from the outer container. 
         [0080]    As can be understood from  FIGS. 1-3 , the configuration of the tabs  2  is advantageous because the tabs  2  are outside the contents containment area of the liner  1 . Thus, if a tab  1  breaks, a seal  23 - 30  is not ruptured and the liner  1  does not end up leaking. Furthermore, as can be understood from  FIGS. 1-3  and the preceding discussion, in one embodiment, each tab  2  employs all of the layers of any two adjacent portions  6 - 10 . Thus, the tabs  2  have twice the strength of any single portion  6 - 10 . Additionally, unlike some prior art liners that have tabs formed exclusively of tape adhered to the walls of said liners, the tabs  2  of the present liner  1  can rely on the tensile strength of the polymer sheets forming the portions  8 - 10  of the liner  1 . This results in a stronger configuration for the tabs  2 . 
         [0081]    For a better understanding of the deployment of the tabs  2 , reference is now made to  FIGS. 5 a  and 5 b   .  FIG. 5 a    is a top isometric view of the upper portion of the liner  1  in its inflated or filled state with the tabs  2  detached in preparation for engagement with an outer container.  FIG. 5 b    is a vertical sectional view taken along section line  5   b - 5   b  of  FIG. 5 a    of a tab  2  affixed to the surface of an outer container  150 . 
         [0082]    As shown in  FIG. 5 a   , each tab  2  has been separated from its respective top flap  4   a,    4   b,    6   a,    6   b  along its L-shaped perforated boarder  70 . This separation of a tab  2  may be achieved by simply pulling on the tab  2  until its perforated L-shaped boarder  70  gives way. As indicated in  FIG. 5 b   , the tabs  2  when separated have sufficient length to allow them to be affixed to an outside container  150  via an adhesive and/or stitching  155 . Alternatively, the tabs  2  may be of a sufficient length to allow them to be affixed to an outside container via hooks or tie ropes. 
         [0083]    For a continued discussion of the general configuration of one embodiment of the liner  1 , reference is again made to  FIGS. 1-3 . As indicated in  FIG. 2 , the bottom oblique seals  31 ,  32 , the bottom cross seal  42 , and the side seals  23 ,  24  generally define front bottom flaps  4   c,    4   d  out of the front portion  4 . In one embodiment, each front bottom flap  4   c,    4   d  will further include corresponding areas of the side portions  8 ,  10  that are defined by the bottom oblique seals  31 ,  32 , the bottom cross seal  42 , and the side seals  23 ,  24 . 
         [0084]    As shown in  FIG. 3 , the bottom oblique seals  33 ,  34 , the bottom cross seal  42 , and the side seals  25 ,  26  generally define rear bottom flaps  6   c,    6   d  out of the rear portion  6 . In one embodiment, each rear bottom flap  6   c,    6   d  will further include corresponding areas of the side portions  8 ,  10  that are defined by the bottom oblique seals  33 ,  34 , the bottom cross seal  42 , and the side seals  25 ,  26 . 
         [0085]    As can be understood from  FIG. 1 , because the front bottom flaps  4   c,    4   d  are sealed to the rear bottom flaps  6   c,    6   d  by the bottom cross seal  42 , when the liner  1  is inflated or filled and takes its cubical form, the bottom flaps  4   c ,  6   c  extend across the bottom triangular section  8   z  and the bottom flaps  4   d,    6   d  extend across the bottom triangular section  10   z.    
         [0086]    As indicated in  FIGS. 2 and 3 , each longitudinal side seal  23 - 26  has a segment that extends across the respective bottom oblique seal  31 - 34  into the respective bottom flap  4   c,    4   d,    6   c,    6   d.  In one embodiment, as shown in  FIGS. 2 and 3 , these bottom segments  23   b,    24   b,    25   b,    26   b  run from the intersection of the respective oblique seal  31 - 34  and side seal  23 - 26  to a point nearly intersecting the bottom cross seal  42 . In other embodiments, the bottom segments  23   b,    24   b,    25   b ,  26   b  will have a greater or lesser length. In one embodiment, each longitudinal side seal  23 - 26  stops at its intersection with the respective bottom oblique seal  31 - 34  such that there are no bottom segments  23   b,    24   b,    25   b,    26   b.    
         [0087]    As indicated in  FIGS. 2 and 3 , in one embodiment, the bottom flaps  4   c,    4   d ,  6   c,    6   d  are not provided with tabs  2 . In other embodiments, the bottom flaps  4   c,    4   d,    6   c,    6   d  are provided with tabs  2 , which can be configured similarly to those found on the top flaps  4   a,    4   b,    6   a,    6   b.    
         [0088]    For a discussion of the location of the fill and drain orifices of the liner  1 , reference is now made to  FIG. 2 . As shown in  FIG. 2 , the front portion  4  is formed with two openings. Mounted in those openings are two tubular fitments, a drain fitment  50  and fill fitment  52 . The drain fitment  50  is intended to function as a drain and may be located generally equidistant from the two longitudinal side edges  21 ,  22  of the front portion  4  at a point that is almost even with the intersections between the bottom oblique seals  31 ,  32  and the longitudinal side seals  23 ,  24 . The fill fitment  52  is for filling purposes and is typically located close to the intersections of the top cross seal  40  with the top oblique seals  27 ,  28 . In one embodiment, the liner  1  will only have a drain fitment  50 . In another embodiment, the liner  1  will only have a fill fitment  52 . 
         [0089]    For a discussion of one method of securing the fitments  50 ,  52  to the front portion  4 , reference is now made to  FIG. 6 , which is a cross sectional view of one type of fill fitment  52  taken along line  6 - 6  of  FIG. 2 . As indicated in  FIG. 6 , the fill fitment  52  comprises two parts, a fixed tubular part  56  and a cap  62 . The fixed tubular part  56  has a flange  58  that underlies and is sealed to the front portion  4  by a circular seal  60 . The cap  62  is releasably attached to and closes off the tubular part  56 . The cap  60  may be attached to the tubular part  56  by a screw, bayonet, snap-fit or other suitable form of connection known in the art. 
         [0090]    For a better understanding of how the four portions  4 - 10  join together and how the liner  1  appears when inflated or filled, reference is again made to  FIG. 1 . As illustrated in  FIG. 1 , the liner  1  assumes the general shape of a cube or a rectangular parallelepiped when is inflated or filled, with the side portions  8 ,  10  unfolding to eliminate the gussets. The front portion  4  forms a front wall, the rear portion  6  forms a rear wall, and the side portions  8 ,  10  form opposite sidewalls. 
         [0091]    As shown in  FIG. 1 , because of the arrangement of the oblique seals  27 - 34  in relation to the longitudinal seals  23 - 26  and cross seals  40 ,  42 , the four portions  4 - 10  come together to form the top and bottom walls of the liner  1 . As illustrated in  FIG. 1 , the filler fitment  52  is located at the top of the liner  1  and the drain fitment  50  is located at the bottom, front side of the liner  1 . 
         [0092]    As can be understood from  FIG. 1 , when inflated or filled, the liner  1  is self-supporting in the sense that it tends to remain erect and not fall over when its bottom end is resting on a flat floor or platform. When an un-inflated liner  1  is inserted in an outside container, the flexibility of the un-inflated liner  1  allows the drain fitment  50  to be properly positioned in any commodity discharge opening provided in the bottom of the outside container. Once so positioned, the cap  62  of the drain fitment  50  may be removed to initiate the liner-emptying process for an inflated or filled liner  1 . 
         [0093]    As previously explained, the flexibility of the material comprising the four portions  4 - 10  may cause a liner  1  to tend to collapse at its upper portion when the liner  1  is being emptied of its contents via the drain  50 . Such a collapsing of the liner  1  makes it difficult to completely empty the liner  1  of viscous contents such as peanut butter, industrial oil or the like. Thus, it is desirable to support the upper portion of the liner  1  off of an upper portion of the outside container. The tabs  2  of the present invention provide an inexpensive means of supporting the liner  1  off of the outside container. 
         [0094]    As indicated hereinabove, the four portions  4 - 10  that make up the liner may consist of a single ply or two or more plies. In the case of two or more plies, it is to be understood that the plies are separate from one another except in the areas of the seals described above, and that each ply may consist of a single plastic film or be a laminate of two or more materials. 
         [0095]    For a discussion of another embodiment of the liner  1 , reference is now made to  FIGS. 7 and 8 .  FIG. 7  is a top isometric view of the upper portion of the liner  1  in its inflated or filled state with an alternative embodiment of the tabs  2 .  FIG. 8  is a bottom view of the upper portion of the liner  1  depicted in  FIG. 7  in its flattened as-made condition, with part of the liner broken away to reveal the side portions  8 ,  10  above. 
         [0096]    As shown in  FIGS. 7 and 8 , the top flaps  4   a,    4   b,    6   a,    6   b  (depicted in  FIGS. 1-3 ) have been trimmed away along tab edges  100  and oblique edges  102  to form another embodiment of the tabs  2 . The tabs  2  depicted in  FIGS. 7 and 8  have attachment features  3  (as previously discussed in this Detailed Description) for affixing the tabs  2  to an outside container. In one embodiment, each tab  2  also has and a top segment  23   a,    24   a,    25   a,    26   a  that extends along at least a portion of the tab  2  to reinforce the tab  2  by sealing together its layers of the respective portions  4 - 10 . In another embodiment, the tabs  2  are not provided with top segment  23   a,    24   a,    25   a,    26   a.  The four portions  4 - 10  may consist of a single ply or two or more plies as described above. 
         [0097]    In one embodiment, the tabs  2  may have lengths as previously discussed in this Detailed Description. In other embodiments, the tabs  2  may have lengths such that they extend out approximately as far as the top edge  18  of the liner  1 . 
         [0098]    For a discussion of yet another embodiment of the liner  1 , reference is now made to  FIGS. 9 and 10 .  FIG. 9  is a top isometric view of the upper portion of the liner  1  in its inflated or filled state with an open neck top and an alternative embodiment of the tabs  2 .  FIG. 10  is a bottom view of the upper portion of the liner  1  depicted in  FIG. 9  in its flattened as-made condition, with part of the liner broken away to reveal the side portions  8 ,  10  above. 
         [0099]    As indicated in  FIGS. 9 and 10 , in one embodiment, the filler fitment  52  is omitted from the front portion  4  (the hole for the filler fitment  52  is also omitted) and the top oblique seals  27 - 30  are modified by extending them so as to form neck sections  90   a,    90   b,    90   c,    90   d.  While the top oblique seals  27 - 30  are extended to the top end edge  18  of the neck sections  90   a,    90   b,    90   c,    90   d,  the neck sections are not sealed together with a cross-seal  40  (depicted in  FIGS. 1-3 ). 
         [0100]    As shown in  FIG. 9 , when the liner is inflated the neck sections  90   a,    90   b,    90   c,    90   d  of the four portions  4 - 10  form a spout  94  with a substantially square cross-sectional configuration that can be used for filling the liner  1  with a selected liquid or particulate commodity. After the liner  1  has been filled, the spout  94  can be sealed shut by securing together the four sections  90   a,    90   b,    90   c ,  90   d  (e.g., by an adhesive, stitching, stapling, heat sealing, or adding a closure member (not shown) that fits over or inside the spout and seals it to the spout). The four portions  4 - 10  may consist of a single ply or two or more plies as described above. 
         [0101]    The alternative embodiment shown in  FIGS. 9 and 10  may be preferred for certain applications where it is customary to employ liners with spouts (e.g. the applications contemplated for outer containers and liners disclosed in U.S. Pat. No. 6,371,646, issued Apr. 16, 2002 to L. LaFleur, and U.S. Pat. No. 4,596,040, issued Jun. 17, 1986 to A. E. Lafleur et al, both of which are hereby incorporated in their entireties into this Detailed Description). 
         [0102]    In one embodiment, the tabs  2  may have lengths as previously discussed in this Detailed Description. In other embodiments, the tabs  2  may have lengths such that they extend out approximately as far as the top edge  18  of the liner  1 . 
         [0103]    Of course the invention is susceptible of other modifications and may be applied to liners  1  of different constructions. For example, instead of being L-shaped, the perforated lines  70  may be formed as a single line curved in an arc. Alternatively, the perforated lines  70  may run adjacent to the oblique seals  27 - 30  from a point near the intersections between the oblique seals  27 - 30  and the longitudinal side seals  23 - 26  to the top edge  18  such that each tab  2  ends up being all or substantially all of its respective top flap  4   a,    4   b,    6   a,    6   b.    
         [0104]    In one embodiment, the fitments  50 ,  52  may have different structures or shapes. In one embodiment, the filler fitment  52  may be omitted, in which case the drain fitment  50  may also serve as a filler means for the liner by attaching a pump discharge line to pump the contents into the liner  1 . Conversely, the drain fitment  50  may be omitted, in which case the filler fitment  52  may also serve as a drain means for the liner by running a pump suction line down into the liner to remove the contents of the liner  1 . 
         [0105]    Although the preferred construction is a liner that has a substantially cubic shape when inflated (in which case the side portions  8 ,  10  have substantially the same width when unfolded as the front and rear portions  4 ,  6 ), the liner also may be formed so as to have a rectangular parallelepiped shape when inflated (e.g., the side portions  8 ,  10  may have smaller widths than the front and rear portions  4 ,  6 . 
         [0106]    Although the seals whereby the four portions  4 - 10  are connected together are illustrated by single lines, it is to be understood that the cross-seals and the longitudinal and oblique seals that connect the front and rear portions  4 ,  6  to the side portions  8 ,  10  may vary in width and, for example, may extend out to the edges of the four portions  4 - 10 . 
         [0107]    For a discussion of the employment of a winder system with the tabs  2  of the liner  1 , reference is now made to  FIG. 11 .  FIG. 11  is a side elevation of a liner  1  attached to a winder system  110  to facilitate the complete removal of the contents  112  of the liner  1  during the emptying of the liner  1 . As indicated in  FIG. 1 , the tabs  2  extending from the rear portion  6  are attached to the winder  110 . As the tabs  2  are wound about the winder  110 , the bottom rear edge of the liner  1  is elevated. This causes the contents  112  of the liner  1  to flow towards the drain fitment  50 , which facilitates complete removal of the contents  112  from the liner  1 . Because of the length and configuration of the tabs  2 , as previously discussed in this Detailed Description, the tabs  2  are ideal for use with a winder  110 . This is because the tabs  2  have a high tensile strength due to having twice the layers of any sidewall of the liner. Also, should a tab  2  fail, a seam of the liner is less likely to tear and leak. 
         [0108]    Although the present invention has been described with reference to preferred embodiments, persons skilled in the art will recognize that changes may be made in form and detail without departing from the spirit and scope of the invention.