Patent Publication Number: US-7716901-B2

Title: Packaging for particulate and granular materials

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
   This application claims benefit of U.S. Provisional Application No. 60/672,704, filed Apr. 19, 2005, and U.S. Provisional Application 60/574,860, filed May 27, 2004, which are hereby incorporated herein in their entirety by reference. 

   BACKGROUND OF THE INVENTION 
   1. Field of the Invention 
   The present invention relates generally to packaging and, more particularly, to packaging and methods for packaging for particulate and granular materials. 
   2. Description of Related Art 
   Particulate and granular materials are commonly packaged in bags, sacks or other packaging materials (collectively referred to herein as “bags”) constructed of paper. As used herein, the term “particulate materials” refers to powdery materials that generate dust when disturbed, such as during packaging. For purposes of example only and not limitation, particulate materials can include cementitious materials, such as cement and concrete mixes, limestone, fly ash, bottom ash, powdered sugar, etc. As used herein, the term “granular materials” refers to materials that are composed of granules or grains, or have a grainy texture, and which may or may not generate dust when disturbed. For purposes of example only and not limitation, granular materials can include sand, pea gravel, sugar, salt, etc. 
   The conventional paper bags used to package particulate and granular materials are generally closed at one end either when the bag is made or prior to filling by folding the sides of the bag inwardly in an overlapping configuration and then securing the sides together using an adhesive. The bags are filled with the particulate or granular material through the open end of the bag, which is then closed by folding the sides of the bag inwardly in an overlapping configuration and then securing the sides together using an adhesive. 
   Conventional paper bags are structured to allow air to escape from the interior of the bags so that the bags can be compressed when the bags are stacked, such as on a pallet. However, conventional paper bags have several disadvantages. For example, in addition to allowing air to escape, conventional paper bags also can allow fine particles from the particulate or granular material inside the bag to escape, which can result in appreciable amounts of dust, particularly when storing the bags in an enclosed space such as a warehouse or inside a store. Conventional paper bags also are susceptible to rupturing or tearing if not handled properly, which can result in product spillage and waste. Conventional paper bags also allow moisture to permeate the bag, which will typically have an adverse effect on the particulate or granular material inside the bag. For example, where the bag is used to package cementitious material, moisture can lead to curing of the cementitious material inside the bag thereby rendering the product useless. This can be particularly problematic when storing or handling the bags outside where the bags can be exposed to rain, condensation or other wet ambient conditions. Conventional paper bags also can be difficult to load and unload manually when the bags are filled with particulate or granular material. For example, bags used to package cementitious material are typically offered in 29 lb, 44 lb, 50 lb, 60 lb and 80 lb bags, which are heavy and can be difficulty to carry. 
   Accordingly, there remains a need for packaging for particulate and granular material generally and cementitious materials in particular. The packaging should be capable of being filled and sealed using an automated filling machine and should allow the particulate or granular material to be stored so as to minimize leakage, spillage and exposure to moisture. The packaging should also be stackable when filled with particulate or granular material, such as on a pallet, and should also facilitate manual loading and unloading of the filled packaging. 
   SUMMARY OF THE INVENTION 
   The present invention provides package for particulate and granular material. According to one embodiment, the package includes a bag formed of a polymeric material. The bag has first and second ends. The first end of the bag is sealed and the second end of the bag is open. The first end of the bag has a first tab extending therefrom defining at least one aperture therethrough so that the first tab defines a first handle. In one embodiment, the edge of the at least one aperture in the first tab is at least partially sealed. The second end of the bag is structured to be sealed after filling the bag with the particulate or granular material. The second end of the bag has an excess portion structured to be formed into a second tab defining at least one aperture therethrough upon sealing of the second end of the bag so as to define a second handle. In one embodiment, the bag has first and second sides, wherein at least a portion of the first side and/or the second side of the bag defines a textured surface. 
   The present invention provides package for cementitious material. According to one embodiment, the package includes a bag formed of a polymeric material. The bag has first and second ends. The first end of the bag is sealed and the second end of the bag is open. The first end of the bag has a first tab extending therefrom defining at least one aperture therethrough so that the first tab defines a first handle. In one embodiment, the edge of the at least one aperture in the first tab is at least partially sealed. The second end of the bag is structured to be sealed after filling the bag with the cementitious material. The second end of the bag has an excess portion structured to be formed into a second tab defining at least one aperture therethrough upon sealing of the second end of the bag so as to define a second handle. In one embodiment, the bag has first and second sides, wherein at least a portion of the first side and/or the second side of the bag defines a textured surface. 
   The present invention also provides a packaged product containing particulate or granular material. According to one embodiment, the packaged product includes a bag formed of a polymeric material. The bag has first and second sealed ends. The first sealed end has a first tab extending therefrom defining at least one aperture therethrough so that the first tab defines a first handle. The second sealed end has a second tab extending therefrom defining at least one aperture therethrough so that the second tab defines a second handle. In one embodiment, the edge of the at least one aperture in the first tab and/or second tab is at least partially sealed. A particulate or granular material is sealed within the bag, wherein the first and second handles facilitate the handling of the packaged product. In one embodiment, the bag has first and second sides, wherein at least a portion of the first side and/or the second side of the bag defines a textured surface. 
   The present invention also provides a packaged cementitious product. According to one embodiment, the packaged cementitious product includes a bag formed of a polymeric material. The bag has first and second sealed ends. The first sealed end has a first tab extending therefrom defining at least one aperture therethrough so that the first tab defines a first handle. The second sealed end has a second tab extending therefrom defining at least one aperture therethrough so that the second tab defines a second handle. In one embodiment, the edge of the at least one aperture in the first tab and/or second tab is at least partially sealed. A cementitious product is sealed within the bag, wherein the first and second handles facilitate the handling of the packaged cementitious product. In one embodiment, the bag has first and second sides, wherein at least a portion of the first side and/or the second side of the bag defines a textured surface. 
   The present invention also provides a method for packaging particulate or granular material. According to one embodiment, the method includes providing a bag formed of a polymeric material, the bag having first and second ends. In one embodiment, the providing step includes forming the bag. The first end of the bag is sealed and the second end of the bag is open. The first end of the bag has a first tab extending therefrom defining at least one aperture therethrough so that the first tab defines a first handle. In one embodiment, the providing step includes heating a die and forming the at least one aperture through the first tab using the heated die. In one embodiment, the heating step comprises heating the die to between approximately 420° F. to approximately 460° F. The bag is filled with a predetermined amount of particulate or granular material. The second end of the bag is sealed so as to form a second tab extending therefrom. At least one aperture is formed through the second tab so that the second tab defines a second handle. In one embodiment, the forming step comprises heating a die and forming the at least one aperture through the second tab using the heated die. In one embodiment, the heating step comprises heating the die to between approximately 420° F. to approximately 460° F. In one embodiment, substantially all of the air is removed from the interior of the bag. In one embodiment, the removing step comprises compressing the bag. In another embodiment, the removing step comprises evacuating air from the bag prior to the sealing step. In another embodiment, the filling step and the evacuating step are done concurrently. In yet another embodiment, a plurality of bags are stacked on a pallet. In still another embodiment, the plurality of bags are secured to the pallet. 
   The present invention also provides a method for packaging cementitious material. According to one embodiment, the method includes providing a bag formed of a polymeric material, the bag having first and second ends. In one embodiment, the providing step includes forming the bag. The first end of the bag is sealed and the second end of the bag is open. The first end of the bag has a first tab extending therefrom defining at least one aperture therethrough so that the first tab defines a first handle. In one embodiment, the providing step includes heating a die and forming the at least one aperture through the first tab using the heated die. In one embodiment, the heating step comprises heating the die to between approximately 420° F. to approximately 460° F. The bag is filled with a predetermined amount of cementitious material. In one embodiment, the filling step includes filling the bag with approximately 29 lbs, 44 lbs, 50 lbs, 60 lbs or 80 lbs of cementitious material. The second end of the bag is sealed so as to form a second tab extending therefrom. At least one aperture is formed through the second tab so that the second tab defines a second handle. In one embodiment, the forming step comprises heating a die and forming the at least one aperture through the second tab using the heated die. In one embodiment, the heating step comprises heating the die to between approximately 420° F. to approximately 460° F. In one embodiment, substantially all of the air is removed from the interior of the bag. In one embodiment, the removing step comprises compressing the bag. In another embodiment, the removing step comprises evacuating air from the bag prior to the sealing step. In another embodiment, the filling step and the evacuating step are done concurrently. In yet another embodiment, a plurality of bags are stacked on a pallet. In still another embodiment, the plurality of bags are secured to the pallet. 
   The present invention also provides an apparatus for forming handles in polymeric packaging for particulate and granular material. The apparatus includes a die structured to form at least one aperture in the packaging. The apparatus also includes at least one heating element structured to heat the die such that the die seals the edges of the at least one aperture. In one embodiment, the die comprises a forming portion and a backing member. In another embodiment, the at least one heating element is structured to heat the die to between approximately 420° F. to approximately 460° F. 
   Accordingly, there has been provided packaging and associated packaging methods for particulate and granular material generally and cementitious materials in particular. The packaging is capable of being formed, filled and sealed using an automated forming, filling and sealing machine and allows the particulate or granular material to be stored so as to minimize leakage, spillage and exposure to moisture. The packaging is stackable when filled with the particulate or granular material, such as on a pallet, and also facilitates manual loading and unloading of the filled packaging. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The foregoing and other advantages and features of the invention, and the manner in which the same are accomplished, will become more readily apparent upon consideration of the following detail description of the invention taken in conjunction with the accompanying drawings, which illustrate preferred and exemplary embodiments and which are not necessarily drawn to scale, wherein: 
       FIG. 1  is a perspective view illustrating a packaged product, according to one embodiment of the present invention; 
       FIG. 2  is a perspective view illustrating a package for particulate and granular material, according to one embodiment of the present invention; 
       FIGS. 3 and 4  are perspective views illustrating the opening and filling of the package for particulate and granular material of  FIG. 2 , respectively, according to one embodiment of the present invention; 
       FIG. 5  is a perspective view illustrating the evacuation of air from the package for particulate and granular material of  FIG. 4 , according to one embodiment of the present invention; 
       FIG. 6  is a perspective view illustrating the filled package of particulate and granular material of  FIG. 5  after sealing the second end, according to one embodiment of the present invention; 
       FIG. 7  is a perspective view illustrating the apertures formed in the tab extending from the second end of the filled package of  FIG. 6 , according to one embodiment of the present invention; 
       FIGS. 8-13  are partial perspective views illustrating various configurations of the first and/or second handle, according to embodiments of the present invention; 
       FIG. 14  is a partial perspective view illustrating the textured surface of one side of the package of  FIG. 1 , according to one embodiment of the present invention; 
       FIG. 15  is a block diagram illustrating a method for packaging a cementitious material, according to one embodiment of the present invention; 
       FIGS. 16 and 17  are partial perspective views illustrating the formation of the first and/or second handle, according to one embodiment of the present invention; 
       FIGS. 18A and 18B  are partial perspective views illustrating a heated die used to form the first and/or second handle, according to one embodiment of the present invention; 
       FIGS. 18C ,  18 D, and  18 E are perspective, plan and side views, respectively, illustrating a rim on the raised portion of the forming portion of the die, according to one embodiment of the present invention; and 
       FIG. 19  is a block diagram illustrating a method for packaging a cementitious material, according to one embodiment of the present invention. 
   

   DETAILED DESCRIPTION OF THE INVENTION 
   The present invention now will be described more fully hereinafter with reference to the accompanying drawings, in which some, but not all embodiments of the invention are shown. This invention may be embodied in many different forms and should not be construed as limited to the embodiments set forth herein; rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art. Like numbers refer to like elements throughout. 
   Referring to  FIG. 1 , there is illustrated a packaged product  10  of particulate or granular material, according to one embodiment of the present invention. The packaged product  10  includes a bag  12  formed of a polymeric material. The type of polymeric material and thickness of the material can vary depending on the type and weight of the particulate or granular material to be packaged. According to one embodiment, packaged cementitious products  10  are typically distributed in 29 lb, 44 lb, 50 lb, 60 lb, 80 lb, and 90 lb sizes, although other sizes can be provided. The polymeric material can include, but is not limited to, a blend of linear low density polyethylene, which provides elasticity to the bag, and high density polyethylene, which provides puncture resistance, and metallocenes, which provides strength. For example, according to one embodiment the bag  12  is formed of a blend of high density polyethylene, linear low density polyethylene, and metallocenes having a thickness of approximately 3 mil to 6 mil and, preferably, approximately 4 mil to 5 mil, and more preferably, approximately 5 mil. In one embodiment, all or portions of the polymeric material of the bag  12  are substantially transparent. In other embodiments, all or portions of the polymeric material of the bag  12  are translucent or opaque. For example, all or portions of the polymeric material of the bag  12  can be colored based upon or to denote the strength or composition of the particulate or granular material inside the bag to provide visual differentiation between different products  10  so that purchasers can easily identify the different products. In other embodiments, one or more colors can be printed on the bag  12 , such as by screen printing, as can information relating to the contents of the bag and/or the producer of the bag (such as trademarks, etc.) 
   As illustrated in  FIG. 1 , the bag  12  has a first sealed end  14  and a second sealed end  16 . The first and second sealed ends  14 ,  16  can be formed using a variety of techniques, as is known in the art. For example, the first and second sealed ends  14 ,  16  can be formed by applying energy, such as heat or irradiation, to one or both sides of the bag  12  at the first and second ends so as to fuse the sides of the bag together. This energy can be applied using a manual or automated filling machine. For example, a relatively thin Teflon coated bar can be heated and pressed against one side of the bag to fuse the sides together. The first sealed end  14  has a first tab  18  extending therefrom defining at least one aperture  20  therethrough so that the first tab defines a first handle  22 . Similarly, the second sealed end  16  has a second tab  24  extending therefrom defining at least one aperture  26  therethrough so that the second tab defines a second handle  28 . While not required, as illustrated in  FIG. 1 , the ends of the first and second tabs  18 ,  24  can be fused at the distal edges of the tabs by applying energy, such as heat or irradiation, to the ends of the tabs to further strength the tabs. 
   As illustrated in  FIGS. 8-13 , which are provided for purposes of example only and not limitation, the number of apertures  20 ,  26  and configuration of the apertures of the first and second handles  22 ,  28  can vary depending on the strength and thickness of the polymeric material and the weight of the particulate or granular material to be packaged within the bag  12 . The first and second tabs  18 ,  24  preferably will include a plurality of apertures  20 ,  26 , as illustrated in the exemplary embodiments shown in  FIGS. 8-11  and  13 , or an elongate aperture, as illustrated in exemplary embodiment shown in  FIG. 12 , as this will facilitate handling the bags  12  manually since multiple fingers can be inserted into the corresponding apertures  20 ,  26 . For polymeric materials having lower strengths, the number of apertures  20 ,  26  formed in the first and second tabs  18 ,  24  can be reduced so as not to compromise the strength of the corresponding tab  18 ,  24 . Preferably, the apertures  20 ,  26  are configured so as to minimize sharp corners or notches along the edges  25  to thereby minimize potential stress concentrations along the edges of the apertures. For bags  12  packaging larger or heavy loads of material, the apertures  20 ,  26  can be located a predetermined distance from the sealed ends  14 ,  16  of the bag and the distal end of the corresponding tab  18 ,  24  to further strengthen the handles  22 ,  28 . For example, according to one embodiment, the apertures  20 ,  26  can be located approximately 6 mm to 10 mm from the sealed ends  14 ,  16  of the bag and the distal end of the corresponding tab  18 ,  24 . 
   In forming the apertures  20 ,  26 , the excess material  21  within the apertures can be removed entirely or, as illustrated in  FIG. 1 , a small section of material  21   a  can remain after forming the apertures that connects the excess material to the corresponding first or second tabs  18 ,  24 . According to the embodiment illustrated in  FIG. 1 , when the bag  12  is lifted or picked up, the person lifting the bag inserts their finger(s) into the corresponding apertures  20 ,  26  thereby pushing the excess material  21  through the aperture. 
   As discussed more fully below, the apertures  20 ,  26  in the first and second tabs  18 ,  24  can be formed using a heated die such that the edges  25  of the apertures are at least partially sealed. In one embodiment, the die can include a rim so that the seal at the edges  25  of the apertures  20 ,  26  extends beyond the edges a predetermined distance. It has been found that using a heated die to at least partially seal the edges  25  of the apertures  20 ,  26  strengthens the material around the apertures and increases the tear resistance of the material and, thus, strengthens the first and second handles  22 ,  28  of the bag  12 . Advantageously, the first and second handles  22 ,  28  of the bag  12  of the present invention do not require any further reinforcement, such as the application of reinforcing tape, in order to support the material stored in the bag. In addition, apertures  20 ,  26  having sealed edges  25  have the further benefit of containing any material that may escape into the first or second tabs  18 ,  24  due to a ruptured or defective first or second sealed end  14 ,  16 , respectively, thus further minimizing product spillage. 
   As illustrated in  FIG. 1 , the bag  12  includes first and second sides  32   a ,  32   b . According to one embodiment of the present invention, as illustrated in  FIGS. 1 and 14 , at least a portion of at least one of the first and second sides  32   a ,  32   b  defines a textured surface  34 , which creates friction between the corresponding bag  12  and an adjacent bag or surface. The friction created by the textured surface  34  prevents shifting of the bag during transport or storage thereby enabling the bags  12  to be stacked, such as on a pallet (not shown), for purposes of shipping the packaged product  10  in bulk. The types of textured surfaces  34 , as well as the configuration and the number of areas of textured surface (for example,  FIG. 1  illustrates two parallel areas of textured surface having a linear configuration) can vary provided sufficient friction is created between the corresponding bag  12  and an adjacent bag or surface to prevent shifting of the bag during transport or storage. As illustrated in  FIG. 14 , the textured surface  34  comprises a plurality of protuberances or raised members. In other embodiments (not shown), the textured surface  34  can comprise a plurality of recessed surfaces or dimples. Other types of textured surface  34  can be provided as well. In one embodiment, at least a portion of both the first and second sides  32   a ,  32   b  defines a textured surface  34 . 
   As illustrated in  FIG. 2 , the bag  12  can also include first and second gusseted sides  33   a ,  33   b . Alternatively, the bag  12  can also be a non-gusseted bag. In one embodiment (not shown), the gusseted sides  33   a ,  33   b  can include perforations to allow air to escape from the bag  12 , such as during filling of the bag with cementitious material, when using a bag flattener, and/or when stacking the bag for storage or shipping. The perforations can be formed using a variety of cutting techniques. In one embodiment, the perforations are formed using heated needles (also known as “microperfing”) or a laser. In another embodiment (not shown), the gusseted bag  12  can include K seals at the corners of the first and second sealed ends  14 ,  16 , as is known in the art, to provide the packaged product  10  with a generally rectangular or square configuration. 
   Referring to  FIG. 2 , there is illustrated a package  36  for particulate and granular materials, according to one embodiment of the present invention, that is used to form the product  10 . The package  36  includes a bag  42  formed of a polymeric material, as discussed above. The bag  42  can be formed using a variety of techniques, such as mono-extrusion or co-extrusion. The bag  42  has a first sealed end  44  and a second end  46 . The first sealed end  44  is formed as discussed above and includes a first tab  48  extending therefrom defining at least one aperture  50  therethrough so that the first tab defines a first handle  52 . The second end  46  of the bag  42  is open so that the bag can be filled with the particulate or granular material. As discussed above, the first and second sides  62   a, b  of the bag  42  can be provided with a textured surface  64 . In addition, the bag  42  can also include first and second gusseted sides  63   a ,  63   b.    
   According to one embodiment, the product  10  is formed from the package  36  in several steps, as illustrated in  FIGS. 3-7 . Referring to  FIGS. 3 and 4 , the bag  42  is filled with a predetermined amount or weight of particulate or granular material  60 .  FIG. 3  illustrates the second end  46  of the bag  42  being opened using suction cups  41 .  FIG. 4  illustrates the bag  42  being filled with a chute  43  as the edges of the edges of the second end  46  of the bag are secured against the chute with clamps  45 . In one embodiment, as illustrated in  FIG. 5 , once the bag  42  is filled with material  60  the air inside the bag can be substantially removed by evacuating the bag using a vacuum or other suction device  47  so as to compress the bag around the material inside the bag. Alternatively, in another embodiment (not shown), the air inside the bag  42  can be substantially removed using a bag flattener after the packaged product  10  is formed. In one embodiment, as illustrated in  FIG. 5 , the inside edges of the second end  46  of the bag  42  preferably are cleaned prior to forming the second handle  58  using air and/or a cleaning device  49 , which moves from side to side to dislodge any particles located on the inside edges.  FIGS. 3-5  are provided for purposes of illustration only and not limitation, as the machinery or process used to fill the bag  42 , clean the inside edges of the second end  46  of the bag  42 , or evacuate air from inside the bag can vary depending on the type of particulate or granular material, the weight of the product  10  being made, the dimensions of the bag, etc. 
   As illustrated in  FIG. 6  and as discussed above, once the inside edges of the second end  46  of the bag  42  are cleaned, the second end  46  of the bag is sealed to thereby form a second sealed end  66  and a second tab  54 . In this regard, and as illustrated in  FIG. 2 , the second end  46  of the bag  42  has an excess portion  51  structured to be formed into the second tab  54 . While not required, as illustrated in  FIG. 6 , the first and second tabs  48 ,  54  can also be sealed at the distal edges of the tabs, as discussed above, to form a double seal to further strengthen the tabs. As illustrated in  FIG. 7 , at least one aperture  56  can be formed in the second tab  54  (such as by cutting or die stamping the second tab) so as to define a second handle  58 . 
   According to another embodiment of the present invention (not shown), the evacuation of the air from the bag  42  can occur concurrently with the step of filling the bag with the material  60 . For example, one or more probes can be inserted into the interior of the bag  42  and can evacuate the air from the bag as the bag is filled with material  60 . Thereafter, the second end  46  of the bag  42  can be sealed, as discussed above. 
   In one embodiment, the package  36  is preformed. In another embodiment, the package  36  is formed from a roll of tubular film material (not shown). According to this embodiment, the first end of the bag is sealed to thereby form a first sealed end  44  and a first tab  48 . At least one aperture  50  can be formed in the first tab  48  (such as by cutting or die stamping the second tab) so as to define a first handle  52 . In one embodiment, the apertures  50  are formed in the first tab  48  and then the first end of the bag is sealed to form the first sealed end  44 . The package  36  can be cut from the roll of tubular film material prior to, concurrently with, or after forming the first sealed end  44 . 
   Referring to  FIGS. 16-17 , there is illustrated an apparatus  80  used to form the apertures  50 ,  56  in the first and second tabs  48 ,  54 , respectively, according to one embodiment of the present invention. The apparatus  80  includes a die  82  and at least one heating element  84 . The die  82  can include a forming portion  86  (as illustrated in  FIGS. 18A and 18B ) and a backing member  88 . As illustrated in  FIGS. 16 and 17 , the apparatus  80  can include a housing  90  structured to receive the forming portion  86  of the die  82 . In one embodiment, a hydraulic or pneumatic cylinder (not shown) seated within the housing  90  is used to move the forming portion  86  of the die  82  toward the backing member  88  when forming the apertures  50 ,  56  in the first and second tabs  48 ,  54 . As illustrated in  FIG. 17 , the apparatus  80  can include a pair of clamps  92  to secure the bag  42  when forming the apertures  50 ,  56  in the first and second tabs  48 ,  54 . 
   Referring to  FIGS. 18A and 18B , the forming portion  86  of the die  82  can include a plate or block  94  having a first side  94   a  and a second side  94   b . The first side  94   a  includes a raised portion  96  configured to form the apertures  50 ,  56  in the first and second tabs  48 ,  54  thereby forming the first and second handles  22 ,  28 . In one embodiment, the second side  94   b  defines one or more apertures  98  structured to receive a corresponding heating element  84 . The heating element or elements  84  can comprise an electrical resistance heater, such as the FIREROD® brand of heaters distributed by Watlow Electric Manufacturing Company of St. Louis, Mo. In other embodiments, other types of heating elements  84  can be used, including induction coils, convection heaters, lasers, etc. In one embodiment, the heating element  84  is structured to heat the forming portion  86  of the die  82  to between approximately 420° F. to approximately 460° F. 
   Referring to  FIGS. 18C ,  18 D, and  18 E, in one embodiment the raised portion  96  includes a rim  100  along the circumference of at least a portion of the distal end of the raised portion. The rim  100  can be around the entire circumference of the raised portion  96 , but preferably is present around at least a portion of the circumference of the raised portion that faces away from the excess material  21 . The rim  100  is structured to increase the heated surface area that contacts the first and second tabs  48 ,  54  to thereby enlarge the seal formed about the edges of the apertures  50 ,  56  in the first and second tabs so as to improve the tear resistance of the apertures. 
   The heated die  82  can be used to form the first and second handles  22 ,  28  of the bag  12  of the present invention or, in another embodiment (not shown), the heated die  82  can also be used to form packaging having a single handle by forming one or more apertures in a tab, as discussed above. It has been determined that using a heated die  82  to at least partially seal the edges of the apertures forming the handles strengthens the material around the apertures and increases the tear resistance of the material and, thus, provides a more robust handle. Advantageously, handles formed using the heated die  82  of the present invention do not require any further reinforcement, such as the application of reinforcing tape, in order to support the material stored in the bag  12 . In addition, handle apertures having sealed edges have the further benefit of containing any material that may escape into the corresponding tab due to a ruptured or defective sealed end, respectively, thus further minimizing product spillage. 
   The present invention also provides a method of packaging particulate and granular material generally and cementitious materials in particular. According to one embodiment, as illustrated in  FIG. 13 , the method includes providing a bag formed of a polymeric material, the bag having first and second ends. See Block  71 . The first end of the bag is sealed and the second end of the bag is open. The first end of the bag has a first tab extending therefrom defining at least one aperture therethrough so that the first tab defines a first handle. In one embodiment, the providing step includes forming the bag. See Block  70 . The bag is filled with a predetermined amount of cementitious material. See Block  72 . In one embodiment, the filling step includes filling the bag with approximately 60 lbs of cementitious material. See Block  73 . In another embodiment, the filling step includes filling the bag with approximately 80 lbs of cementitious material. See Block  74 . Substantially all of the air can be removed from the interior of the bag. See Block  75 . The second end of the bag is sealed so as to form a second tab extending therefrom. See Block  76 . At least one aperture is formed through the second tab so that the second tab defines a second handle. See Block  77 . In one embodiment, a plurality of bags are stacked on a pallet. See Block  78 . In another embodiment, the plurality of bags are secured to the pallet. See Block  79 . 
   According to another embodiment, as illustrated in  FIG. 19 , the method includes providing a roll of tubular polymeric film material. See Block  170 . The tubular polymeric film material is dispensed using the automated machine. See Block  171 . The tubular polymeric film is sealed to form a first seal. See Block  172 . The tubular polymeric film material is cut at a predetermined distance from the first seal to form a bag, the bag comprising first and second ends, the first end comprising the first seal and defining a first tab extending therefrom. See Block  173 . The distal edge of the first tab is sealed. See Block  174 . At least one aperture is formed through the first tab so that the first tab defines a first handle. See Block  175 . The bag is filled with a predetermined amount of cementitious material. See Block  176 . The inside edges of the second end of the bag are cleaned. See Block  177 . The second end of the bag is sealed so as to form a second tab extending therefrom. See Block  178 . The distal edge of the second tab is sealed. See Block  179 . At least one aperture is formed through the second tab so that the second tab defines a second handle. See Block  180 . 
   Advantageously, the packaging of the present invention is capable of being filled and sealed using an automated filling machine. This feature is particularly important in connection with particulate materials (such as cementitious materials), which are notoriously difficult to package using automated packaging machinery since the dust can inhibit the machinery from forming a proper seal. The packaging also allows the particulate or granular material to be stored so as to minimize leakage, spillage and exposure to moisture. The packaging is stackable when filled with particulate or granular material, such as on a pallet, and also facilitates manual loading and unloading of the filled packaging. Many modifications and other embodiments of the inventions set forth herein will come to mind to one skilled in the art to which these inventions pertain having the benefit of the teachings presented in the foregoing descriptions and the associated drawings. Therefore, it is to be understood that the inventions are not to be limited to the specific embodiments disclosed and that modifications and other embodiments are intended to be included within the scope of the appended claims. Although specific terms are employed herein, they are used in a generic and descriptive sense only and not for purposes of limitation.