Patent Publication Number: US-7223017-B2

Title: Side gusset bag with reclose feature

Description:
FIELD OF THE INVENTION 
     The invention relates to the field of packaging, and particularly to side gusset pouches and bags with reclosure features. 
     BACKGROUND OF THE INVENTION 
     Pre-made side gusset pouches and bags are commonly used for a variety of products. The bags are often produced by forming a single or mono-web material into a tube. As the tube travels along the bed of the bag machine, the side-gussets are created by plowing a portion of the web into the tube. If a reclose feature is desired on a mono-web bag, it is typically added post production of the bag. This process can be time consuming and costly. Additionally, traditional side-gusset mono-web bags do not incorporate an easy-open feature because of the presence of the side-gussets. 
     SUMMARY OF THE INVENTION 
     In one aspect, the invention is directed to a bag (which is also referred to as a pouch throughout the specification) that includes a first panel, a second panel, at least one gusset and a reclose feature. The first panel has an inner side and an upper edge. The second panel has an inner side and an upper edge. The gusset has an inside edge disposed between the inner side of the first panel and the inner side of the second panel. The reclose feature has two halves of complementary shape and a flange. A first half of the reclose feature is attached to the upper edge of the inner side of the first panel. The second half of the reclose feature is attached to the upper edge of the inner side of the second panel. The flange covers a portion of the inside edge of the gusset. 
     The bag can also include a tab portion integral to the upper edge of the first panel and to the upper edge of the second panel. A seal can be located proximate to the reclose feature. The seal can extend from the upper edge of the first panel and the upper edge of the second panel to a point substantially equal to a bottom edge of the flange. The reclose feature can be a zipper type feature. 
     In another aspect, the invention is directed to a bag constructed of a mono-web material. The bag has at least one gusset and a reclose feature. The gusset has a pair of faces disposed within the bag. The reclose feature has a flange that covers at least a portion of the pair of faces of the gusset. 
     The invention also relates to a method of manufacturing a bag. The method includes the steps of attaching a first half of a reclose feature having a flange to a mono-web film having a left edge and a right edge, removing a portion of the mono-web film adjacent to the reclose feature, and sealing the left edge and the right edge of the mono-web film to each other to create a tube. The method also includes the step of adding at least one gusset to the mono-web tube. The gusset has an inside edge disposed within the tube. After forming the gusset, a second half of the reclose feature is attached to a portion of the tube opposite the first half of the reclose feature. The flange of the reclose feature covers a portion of the inside edge of the gusset and attaches the portion of the inside edge of the gusset to the inner side of the tube. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       For the purpose of illustrating the invention, there is shown in the drawings a form which is presently preferred; it being understood, that this invention is not limited to the precise arrangements and instrumentalities shown. 
         FIG. 1  is a perspective view of a bag constructed according the principles of the invention with parts of the tab portion cut away. 
         FIG. 2  is a schematic view of a mono-web used to construct the bag of  FIG. 1 . 
         FIG. 3A  is a schematic sectional view of the reclose feature and the bag of  FIG. 1  proximate the upper edges before a process step of the method of making the bag. 
         FIG. 3B  is a schematic section of the reclose feature and the bag of  FIG. 1  proximate the upper edges after a process step of the method of making the bag. 
         FIG. 4A  is a transverse sectional view of the bag of  FIG. 1  taken above the reclose feature. 
         FIG. 4B  is an enlarged view of a portion of  FIG. 4A . 
     
    
    
     DETAILED DESCRIPTION OF THE DRAWINGS 
     In the drawings, in which like numerals indicate like elements, there is shown a bag constructed according the principles of the present invention. With reference to  FIGS. 1 ,  2 ,  3 A, and  3 B a bag  10  includes a first panel  15 , a second panel  20 , at least one gusset  25 , a reclose feature  30  having a flange  32 , and easy-open tabs  35 . The bag  10  can be a mono-web construction of a film  40 . 
     The film  40  can be plastic, such as low, medium or high density polyethylene, polypropylene, polyester (PET), polyamide or any other material that is commonly used in the packaging industry, copolymers, or blends thereof. The film  40  can be a single layer cast or blown film, a multi-layer coextrusion or laminate. The film  40  can also include one or more layers of paper, metal foil, vacuum deposited metal or inorganic layer of aluminum or silicon oxide and/or a polymer barrier layer, such as ethylene vinyl alcohol or polyvinylidene chloride. It is an important aspect of the invention that the material be capable of allowing a gusset to be formed. 
     The first panel  15  and the second panel  20  collectively form the mono-web film  40 . The mono-web film  40  has a left edge  45  that is also the left edge of the first panel  15  and a right edge  50  that is the right edge of the second panel  20 . The first panel  15  includes an inner side  55 , an outer side  60 , an upper edge  65  and a bottom edge  70 . The second panel  20  includes an inner side  75 , and outer side  80 , an upper edge  85  and a bottom edge  90 . If the film  40  is a multi-layer film, it is preferred that at least the inner layer, which forms inner sides  55  and  75 , be a heat sealable layer. 
     The reclose feature  30  includes a first half  30 A having a complimentary design to a second half  30 B. The two halves  30 A,  30 B cooperate to allow the bag  10  to be opened and sealed repeatedly. Each half  30 A,  30 B of the reclose feature  30  can include a flange  32 A,  32 B. Alternatively, only the second half  30 B of the reclose feature  30  includes a flange  32 B. One example of the reclose feature  30  is a zipper type feature. As used herein, the expression zipper type feature includes press-to-close and slide-style zippers. Numerous other types of reclose features, such as a Velcro type feature, could be used as well. The reclose feature  30  can be constructed of plastic material; however, other materials can also be used. 
     During the production of the bag  10 , a continuous strip of the mono-web film  40  travels along the bed of a bag machine. The dimensions of the bag features (e.g., gussets  25  and easy-open tabs  35 ) are predetermined and controlled by the machine operator or a computer program. According to the desired construction, the reclose feature  30  is applied to a portion of the first panel  15 . The halves  30 A,  30 B of the reclose feature  30  are mated to each other when the reclose feature is applied to the first panel  15 . As such, the first half  30 A is attached to the first panel  15  and the second half  30 B extends substantially orthogonal from the first panel  15 . The reclose feature  30  can be attached to the inside surface  55  by heat, ultrasonically, using adhesives or any other method known to those skilled in the art. It is also possible to independently attach the halves  30 A,  30 B to their respective panels  15 ,  30 . ( FIG. 3A  is shown according to the latter possibility to help illustrate the relationship between the flange  32 B and the top of the gusset.) 
     At least one portion  95  of the mono-web film  40  is removed from each of the first panel  15  and the second panel  20 . If more than one gusset is desired, multiple portions  95 A,  95 B,  95 C are removed from the mono-web  40 . As shown, removed portion  95 B cooperates with one gusset  25 A portion and removed portions  95 A,  95 C cooperate with a second gusset portion  25 B. The removed portions  95  define the upper edges  65  and  85  of the first panel  15  and second panel  20 , respectively. The upper edges  65  and  85  can be either of the horizontal edges created by the removed portion  95 . The removed portions  95  have a width equal to or slightly greater than the desired size of the gusset  25 . Removing a portion of the web  40  greater than the width of the gusset  25  provides segments  100 A,  100 B of the mono-web  40  that are adjacent to each side of the reclose feature  30 . The segments  100 A,  100 B can be used to provide a seal adjacent to the reclose feature  30 , which is described in more detail below. 
     In addition to removing the portions  95 , a section  98  of the web  40  above the portion  95  and above the reclose feature  30  can be removed by the user when the bag  10  is opened. As shown in  FIG. 2 , the section  98  is located above the horizontal dashed line. Removing the section  98  creates the easy-open tabs  35 . If the tabs  35  run the width of the bag, as shown in  FIG. 2 , and the film  40  has been transversely oriented, a side notch can be used to allow convenient removal of the section  98 . Alternatively, the section  98  can be created by laser scoring, perforation, or other means, to create a line of weakness. In that case, easy-open tabs  35  can be shorter than the width of the bag  10 , as shown in  FIG. 1 . 
     The right edge  50  of the mono-web  40  is attached to the left edge  45  of the mono-web  40  to create a tube. The left edge  45  and right edge  50  can be sealed to one another by heat sealing, sonic welding, adhesives, or other means. The seal creates an edge joint, lap seal, or fin seal. If a fin seal is to be formed, additional width can be provided at each edge  45 ,  50 . Additional width can be provided at one of the edges if a lap seal is desired. If it is desired for the seal to be formed in the back panel, rather than inside the gusset  25 B, the panel  20  can be split and a portion of the panel  20  provided on each side of the panel  15 . 
     Gussets  25 A,  25 B are added to the bag  10  after the tube is formed. The gussets can be added by plowing a portion of the web  40  into the tube as it travels along the bag machine. Alternatively, the gussets  25  can be added by folding the mono-web  40  prior to forming the tube or after forming the tube. The folds in the mono-web  40  that represent the gussets  25 A,  25 B are shown by the vertical dashed lines of  FIG. 2 . The gussets  25  allow the bag  10  to expand as material is added to the bag  10 . Each gusset  25  has a pair of faces  105 A,  105 B (referred to generally as faces  105 ) that are disposed inside the bag  10 . The faces  105  have an inside edge  110  that is disposed between the inner side  55  of the first panel  15  and the inner side  75  of the second panel when the tube is formed. As shown in  FIG. 2 , the inside edge  110 B of gusset  25 B can be the seal that is created by joining the left edge  45  with the right edge  50  of the web  40 . 
     Once the gussets  25  are formed, the second half  30 B of the reclose feature  30  is attached to the inner side  75  of the second panel  20 . The flange  32 B of the second half  30 B of the reclose feature  30  covers a portion of the inside edge  110  and the faces  105  of the gusset  25 , as shown in  FIGS. 3A and 3B . In  FIG. 3A  when the second half  30 B of the reclose feature  30  is applied to the inner side  75  of the second panel  20 , the flange  32 B covers the inside edge  110  and the faces  105  of the gusset  25 . The faces  105  cause the flange  32 B to protrude from the inner side  75  of the second panel  20 . The second half  30 B of the reclose feature  30  is secured to the inner side  75  of the second panel  20  by fusion, adhesion, or other similar means. Similarly, the flange  32 B and the faces  105  of the gusset  25  are secured to the inner side  75  of the second panel  20 . Heat can be used to secure the flange  32 B to the faces  105  of the gusset  25 . As such, the faces  105 , the flange  32 B, and the second panel  20  can fuse together in the region that is heated to form one contiguous piece of material. After heating, the flange  32 B covers a portion of the faces  105  and a portion of the inside edge  110  of the gusset  25 . The mouth of the bag  10  does not open as widely as the body of the bag because a portion the gussets  25  at the mouth of the bag are sealed behind the flange  32 B of the second half  30 B of the reclose feature  30 . 
     If the width of the portion  95  is greater than the size of the gusset  25 , the segments  100 A and  100 B of the first panel  15  can be sealed to the respective segments  10 A′ and  100 B′ (not shown) of the second panel  20 . As shown in  FIGS. 4A and 4B , the seal  115  helps create an airtight bag  10 . The seal  115  includes the segments  10 A,  10 A′,  100 B,  100 B′ portions of the faces  105  of the gussets  25 , portions of the first panel  115  and portions of the second panel  20 . To further ensure an airtight seal, portions  120  of the reclose feature  30  can also be incorporated into seal  115 . The seal  115  also reinforces the strength of the bag edges to prevent the bag  10  from being damaged during opening. 
     The bottom of the bag  10  can be formed by heat sealing the bottom edges  70 ,  90  together. If a stand-up pouch is desired, a second web of material can be used to form the bottom. The bottom of the bag  10  can also include a gusset feature to allow the bottom of the bag to expand in size and increase the total volume of the bag  10 . 
     The bag  10  can be a pre-made type bag or can be constructed on a vertical form/fill/seal (VFSS) machine or a horizontal form/fill/seal (HFSS) machine. In such an embodiment, the material to be placed in the bag  10  is added after forming the tube of the mono-web material. 
     A variety of modifications to the embodiments described will be apparent to those skilled in the art from the disclosure provided herein. Thus, the present invention may be embodied in other specific forms without departing from the spirit or essential attributes thereof and, accordingly, reference should be made to the appended claims, rather than to the foregoing specification, as indicating the scope of the invention.