Abstract:
In embodiments of the invention, a T-shirt bag includes a breakout die cut between a rack hook die cut and a bag opening. Such breakout die cuts may thus limit tears from reaching the edge of the bag opening. In embodiments of the invention, a T-shirt bag includes multiple rack hook die cuts to accommodate dispensing racks having rack hooks in different positions. Such a T-shirt bag may thus enjoy wider application than conventional bags. Moreover, the multiple rack hook die cuts may further lessen the chance that a tear caused by tugging or elevated bags during loading will reach the edge of the bag opening.

Description:
BACKGROUND AND SUMMARY 
       [0001]    1. Field of the Invention 
         [0002]    The invention relates generally to thermoplastic bags and stacks of such bags, and more particularly, but without limitation, to improvements in die cuts associated with a rack hook mounting area of the thermoplastic bags. 
         [0003]    2. Description of the Related Art 
         [0004]    Thin-walled thermoplastic bags with an open top side are commonly used in retail stores to bundle consumer purchases at a point of sale. In the bagging and retail industries, a T-shirt or vest bag refers to a bag that has two carrying handles extending from the top side of the bag body on opposite sides of the bag opening, because such handles loosely resemble the short sleeves of a T-shirt or shoulder straps of a vest. 
         [0005]    In retail stores, a stack of T-shirt bags is typically placed on a dispensing rack so that each bag in the stack can be individually opened, filled with consumer goods, and removed from the rack. T-shirt bags usually communicate with the rack in three places: a first and second rack arm are threaded through corresponding die cuts or other holes in the first and second handles; and a rack hook passes through a die cut or other hole in a center portion of the bag near the bag opening. 
         [0006]    In a typical bag-filling process, a person may first tug on a front portion of a first bag in the stack to widen the opening of the first bag. The bags are configured so that a rear portion of the first bag tends to stick to a second bag in the stack. The person then begins filling the first bag. When the first bag is full, the person may again tug on the first bag to fully release it from the stack, and then lift the bag using the handles. This second tug should also cause a front portion of the second bag in the stack to separate from a rear portion of the second bag, thus automatically opening the second bag to permit immediate filling. 
         [0007]    Conventional T-shirt bags used with such dispensers have many disadvantages, however. For instance, because of repeated tugging, together with the weight of items placed in the bag, the die cuts or other holes associated with the center rack hook tend to tear in the direction of the bag opening. Moreover, it has been observed that store cashiers will sometimes load a single dispensing rack with up to 12 stacks of 50 bags. Because dispensing rack hooks may extend slightly upward from horizontal, this can cause the bottoms of bags near rack hook ends to be raised above the rack base. This mismatch in elevation also promotes tears during filling that begin at the rack hook die cut. When such a tear reaches the edge of the bag opening, the T-shirt bag may further rip or otherwise fail. In addition, because the relative position of the center rack hook may vary between dispensing racks, the application of any single T-shirt bag may be limited. 
         [0008]    For at least the foregoing reasons, improved T-shirt bags and stacks of such bags are needed. 
       SUMMARY OF THE INVENTION 
       [0009]    Embodiments of the invention seek to overcome one or more of the shortcomings described above. In embodiments of the invention, a T-shirt bag includes a breakout die cut between a rack hook die cut and a bag opening. Such breakout die cuts may thus limit tears from reaching the edge of the bag opening. In embodiments of the invention, a T-shirt bag includes multiple rack hook die cuts to accommodate dispensing racks having rack hooks in different positions. Such a T-shirt bag may thus enjoy wider application than conventional bags. Moreover, the multiple rack hook die cuts may operate together to form a relatively large tear zone and lessen the chance that a tear will reach the edge of the bag opening. In embodiments of the invention, the features described above may be used in combination. 
         [0010]    In one respect, the invention provides a thermoplastic bag. The thermoplastic bag includes: a front layer; and a rear layer, each of the front layer and the rear layer including: a top edge; a bottom edge; a first side edge; and a second side edge, the front layer being joined to the rear layer at their respective bottom, first side and second side edges, at least a portion of the front layer top edge and at least a portion of the rear layer top edge forming an opening in the thermoplastic bag, each of the front layer and the rear layer further including: a first rack hook die cut positioned relatively near the top edge and substantially mid-way between the first and second side edges; a first fracture die cut connected to the first rack hook die cut, the first fracture die cut extending toward the top edge; and a breakout die cut positioned between the first fracture die cut and the top edge, the breakout die cut not connected to the top edge, the thermoplastic bag thus configured such that, when in use, a tear will tend to extend from the first rack hook die cut and through the first fracture die cut, the tear terminating in the breakout die cut without reaching the top edge. 
         [0011]    In another respect, the invention provides a thermoplastic bag. The thermoplastic bag includes: a front layer; and a rear layer, each of the front layer and the rear layer including: a top edge; a bottom edge; a first side edge; and a second side edge, the front layer being joined to the rear layer at their respective bottom, first side and second side edges, at least a portion of the front layer top edge and at least a portion of the rear layer top edge forming an opening in the thermoplastic bag, each of the front layer and the rear layer further including: a plurality of rack hook die cuts positioned relatively near the top edge and substantially mid-way between the first and second side edges, the plurality of rack hook die cuts positioned in a column, the column being substantially parallel to the first and second side edges; and a plurality of fracture die cuts, each of the plurality of fracture die cuts connected to a corresponding one of the plurality of rack hook die cuts, each of the plurality of fracture die cuts extending toward the top edge the thermoplastic bag thus configured to receive a rack hook in any one or more of the plurality of rack hook die cuts. 
         [0012]    In yet another respect, the invention provides a stack of thermoplastic bags. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0013]    The present invention will be more fully understood from the detailed description below and the accompanying drawings, wherein: 
           [0014]      FIG. 1  is an illustration of a T-shirt bag, according to an embodiment of the invention; 
           [0015]      FIG. 2  is an illustration of a T-shirt bag, according to an embodiment of the invention; 
           [0016]      FIG. 3  is an illustration of a stack of T-shirt bags, according to an embodiment of the invention; 
           [0017]      FIG. 4  is an illustration of a stack of T-shirt bags, according to an embodiment of the invention; and 
           [0018]      FIG. 5  is an illustration of a stack of T-shirt bags, according to an embodiment of the invention. 
       
    
    
     DETAILED DESCRIPTION 
       [0019]    The invention will now be described more fully with reference to  FIGS. 1 through 5 , in which embodiments of the invention are shown. This invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. In the drawings, reference designators may be duplicated for the same or similar features. 
         [0020]      FIG. 1  is an illustration of a T-shirt bag, according to an embodiment of the invention. In the illustrated embodiment, the T-shirt bag includes a bottom edge weld  105  and handle welds  110  that join a front and rear layer of the T-shirt bag. The T-shirt bag may further include a fold or seam along lines  115 . Cold stake points  120  may be used to temporarily bond portions of the front layer to portions of the rear layer and/or to temporarily bond portions of a first T-shirt bag in a stack to portions of a second T-shirt bag in the stack. As used herein, a cold stake point is equivalent to a compression point. In the alternative or in combination with the cold stake points  120 , a blunt die cutting tool can be used to cold form compression points at the edges of the arm die cuts  125  and/or the rack hook die cut  135 . This material swaging process temporarily bonds portions of a first T-shirt bag in a stack to portions of a second T-shirt bag in the stack. The arm die cuts  125  located in handle portions of the T-shirt bag are configured to receive dispensing rack arms, as will be further discussed with reference to  FIGS. 3-5  below. 
         [0021]    A rack hook region located near the opening of the T-shirt bag includes a rack hook die cut  135 . The rack hook die cut  135  is positioned and configured to receive a dispensing rack hook when the bag is being dispensed. A fracture die cut  140  is connected to the rack hook die cut  135 , extending toward the T-shirt bag opening. The fracture die cut  140  may be, for instance, a frangible or perforated portion of the T-shirt bag that is weaker than surrounding T-shirt bag material. A breakout die cut  130  is positioned between the fracture die cut  140  and the T-shirt bag opening. In the illustrated embodiment, the breakout die cut  130  is not in direct communication with the fracture die cut  140 . 
         [0022]    The T-shirt bag illustrated in  FIG. 1  is thus configured such that when the T-shirt bag is being dispensed from a dispensing rack, a tear that originates in the area of the rack hook die cut  135  in the direction of the T-shirt bag opening will tend to propagate through the fracture die cut  140 . The tear may terminate in the fracture die cut  140 . Alternatively, the tear may further propagate from the fracture die cut  140  to the breakout die cut  130  and terminate in the breakout die cut  130  without reaching the edge of the T-shirt bag opening. 
         [0023]    Variations to the T-shirt bag illustrated in  FIG. 1  are possible. For instance, in an alternative embodiment, the T-shirt bag may not include a fold or seam along lines  115 . Moreover, the cold stake points  120  could vary in quantity and location, according to design choice. Nor is the invention intended to be limited by the shape of the rack hook die cut  135 , breakout die cut  130  and arm die cuts  125 . In an alternative embodiment, the fracture die cut  140  could be in direct communication with both the rack hook die cut  135  and the breakout die cut  130 . 
         [0024]      FIG. 2  is an illustration of a T-shirt bag, according to an embodiment of the invention. In the illustrated embodiment, the T-shirt bag includes a bottom edge weld  205  and handle welds  210  that join a front and rear layer of the T-shirt bag. The T-shirt bag may further include a fold or seam along lines  215 . Cold stake points  220  may be used to temporarily bond portions of the front layer to portions of the rear layer and/or to temporarily bond portions of a first T-shirt bag in a stack to portions of a second T-shirt bag in the stack. In the alternative or in combination with the cold stake points  220 , a blunt die cutting tool can be used to cold form compression points at the edges of the arm die cuts  225  and/or rack hook die cuts  235 ,  236 , and/or  237 . This material swaging process temporarily bonds portions of a first T-shirt bag in a stack to portions of a second T-shirt bag in the stack. This method may also be used at the bag ends near welds  210  and  205  to temporarily bond the cut edges. The arm die cuts  225  located in handle portions of the T-shirt bag are configured to receive dispensing rack arms, as will be further discussed with reference to  FIGS. 3-5  below. 
         [0025]    A rack hook region located near the opening of the T-shirt bag includes rack hook die cuts  235 ,  236 , and  237 . The rack hook die cuts  235 ,  236 , and  237  are positioned and configured so that the T-shirt bag can receive a dispensing rack hook through any one of the rack hook die cuts  235 ,  236  or  237  when the bag is being dispensed. The T-shirt bag also includes fracture die cuts  240 ,  241 , and  242 . Each of the fracture die cuts  240 ,  241 , and  242  are connected to a corresponding one of the rack hook die cuts  235 ,  236 , and  237 . Each of the fracture die cuts  240 ,  241 , and  242  may be, for instance, a frangible or perforated portion of the T-shirt bag that is weaker than surrounding T-shirt bag material. A breakout die cut  230  is positioned between the fracture die cut  240  and the T-shirt bag opening. In the illustrated embodiment, the breakout die cut  230  is not in direct communication with the fracture die cut  240 . 
         [0026]    The T-shirt bag illustrated in  FIG. 2  is thus configured such that when the T-shirt bag is being dispensed from a dispensing rack, a tear that originates in any of the rack hook die cuts  235 ,  236 , or  237  in the direction of the T-shirt bag opening will not likely reach the edge of the bag opening. For instance, a tear originating in the rack hook die cut  236  in the direction of the bag opening will tend to propagate through the fracture die cut  241 . The tear may terminate in the fracture die cut  241 . Alternatively, the tear may further propagate from the fracture die cut  241  to the rack hook die cut  235 . The tear may then terminate in the rack hook die cut  235 . Alternatively, the tear may further propagate from the rack hook die cut  235  to the fracture die cut  240 . The tear may terminate in the fracture die cut  240 . Alternatively, the tear may further propagate from the fracture die cut  240  to the breakout die cut  230  and terminate in the breakout die cut  230  without reaching the edge of the T-shirt bag opening. 
         [0027]    Variations to the T-shirt bag illustrated in  FIG. 2  are possible. For instance, in an alternative embodiment, the T-shirt bag may not include a fold or seam along lines  215 . Moreover, the cold stake points  220  could vary in quantity and location, according to design choice. Nor is the invention intended to be limited by the shape of the rack hook die cuts  235 ,  236 , and  237 , the breakout die cut  230  and the arm die cuts  225 . Because the rack hook die cuts  235 ,  236 , and  237  can work in cooperation to extend a controlled tear zone, the breakout die cut  230  can be omitted. In an alternative embodiment, the fracture die cut  240  could be in direct communication with both the rack hook die cut  235  and the breakout die cut  230 . Likewise, the fracture die cut  241  could be in direct communication with both the rack hook die cut  236  and the rack hook die cut  235 , and the fracture die cut  242  could be in direct communication with both the rack hook die cut  237  and the rack hook die cut  236 . 
         [0028]      FIG. 3  is an illustration of a stack of T-shirt bags, according to an embodiment of the invention. The stack  315  may include multiple T-shirt bags of the type described with reference to  FIG. 1 , including multiple T-shirt bags of any disclosed variation of the bag illustrated in  FIG. 1 . 
         [0029]      FIG. 3  partially illustrates a dispensing rack having two dispensing rack arms  305  and a dispensing rack hook  310 . When the stack  315  is assembled to the dispensing rack, each of the two dispensing rack arms  305  communicate with a corresponding one of the two arm die cuts  125  in each of the bags in the stack  315 . In addition, the dispensing rack hook  310  communicates with the rack hook die cut  135  in each of the bags in the stack  315 . 
         [0030]      FIG. 4  is an illustration of a stack of T-shirt bags, according to an embodiment of the invention. The stack  405  may include multiple T-shirt bags of the type described with reference to  FIG. 2 , including multiple T-shirt bags of any disclosed variation of the bag illustrated in  FIG. 2 . 
         [0031]      FIG. 4  partially illustrates a dispensing rack having two dispensing rack arms  305  and a dispensing rack hook  310 . When the stack  405  is assembled to the dispensing rack, each of the two dispensing rack arms  305  communicate with a corresponding one of the two arm die cuts  225  in each of the bags in the stack  405 . In addition, the dispensing rack hook  310  communicates with the rack hook die cut  235  in each of the bags in the stack  405 . 
         [0032]      FIG. 5  is an illustration of a stack of T-shirt bags, according to an embodiment of the invention. The embodiment in  FIG. 5  is substantially the same as the embodiment illustrated in  FIG. 4 , except that the dispensing rack includes a dispensing rack hook  505  instead of a dispending rack hook  310 . The dispensing rack hook  505  is positioned further from the opening of each of the T-shirt bags in stack  405 . Accordingly, when the stack  405  is assembled onto the dispensing rack, the dispensing rack hook  505  is in communication with the rack hook die cut  237  rather than the rack hook die cut  235 . A comparison  FIGS. 4 and 5  thus illustrate that the stack  405  may enjoy wider application than the stack  315 . 
         [0033]    Embodiments of the invention thus provide many benefits. In one respect, embodiments of the invention include one or more fracture die cuts, a breakout die cut, and/or multiple rack hook die cuts to prevent tears that originate in a rack hook die cut from reaching an edge of the T-shirt bag opening. In another respect, embodiments of the invention provide multiple rack hook die cuts that permit a T-shirt stack to be dispensed from more than one dispensing rack configuration. 
         [0034]    It will be apparent to those skilled in the art that modifications and variations can be made without deviating from the spirit or scope of the invention. For example, alternative features described herein could be combined in ways not explicitly illustrated or disclosed. Moreover, features of the invention could be applied to bags and stacks that are other than the T-shirt type illustrated in the figures. Thus, it is intended that the present invention cover any such modifications and variations of this invention provided they come within the scope of the appended claims and their equivalents.