Patent Publication Number: US-3877352-A

Title: Method for producing thermoplastic bag with handle

Description:
United States Patent 1 [111 3,877,352  
 Brieske Apr. 15, 1975 METHOD FOR PRODUCING Primary Examiner-Roy Lake THERMOPLASTIC BAG WITH HANDLE [75] Inventor: Bernard F. Brieske, Palatine, Ill.  
 [73] Assignee: Vision Wrap Industries, Inc.,  
 Palatine, Ill.  
 [22] Filed: July 5, 1973 [21] App]. No,: 376,681  
 [52] US. Cl. 93/35 H; 93/8 WA [51] Int. Cl B31b 1/86 [58] Field of Search 93/35 H, 8 WA, 35 R [56] References Cited UNITED STATES PATENTS 2,400,759 5/1946 Katz 93/35 H X 3,392,636 7/1968 Lindley 93/35 H X 3,548,723 l2/l970 Sengewald 93/35 H Assistant Examiner-James F. Coan Attorney, Agent, or FirmMcDougall, Hersh &amp; Scott [57] ABSTRACT A thermoplastic bag structure provided with a handle which serves to provide closure means for the bag. The handle is formed from a pair of wide cardboard strips which are secured at parallel edges defining an opening to the bag interior. The Strips defining an opening for receiving the fingers) of the bag user thereby providing the handle feature. By utilizing wide cardboard strips which normally remain in overlying relationship, the bag will remain closed until pulled open and filled. The bag can be economically manufactured by locating the cardboard strips in position for attachment to the parallel bag edges with a heat sealing operation preferably being involved.  
 1 Claim, 5 Drawing Figures METHOD FOR PRODUQING THERMOPLASTIC BAG WITH HANDLE This invention relates to a thermoplastic bag construction, and particularly to a bag construction having an attached handle which also serves as a closure means for the bag. Bags of the general type contemplated by this invention may be utilized as shopping bags or for similar purposes.  
  The production of low-cost thermoplastic bags is wide spread. Particular emphasis is placed on lower cost production since many such bags are distributed free of charge to customers of various establishments.  
  In order to achieve low cost production, the type of materials employed and the type of operating steps involved are of great importance. Thus, large amounts of material and the use of expensive materials is to be avoided. Similarly, the processing steps involved in production cannot be unduly complicated or too numerous.  
  It is a general object of this invention to provide a thermoplastic bag construction which involves the utilization of relatively low cost materials and process steps whereby the bag can be economically produced.  
  It is a more specific object of this invention to provide a bag construction which is relatively simple in design but which combines handle and closure features whereby the advantages of higher cost bags can be achieved.  
  These and other objects of this invention will appear hereinafter and for purposes of illustration, but not of limitation, specific embodiments of the invention are shown in the accompanying drawings in which:  
  FIG. 1 is a perspective view of a bag characterized by the features of this. invention;  
  FIG. 2 is a perspective view of the bag with the handle and bag portions separated;  
  FIG. 3 is a plan view of a blank utilized for forming the handle construction;  
  FIG. 4 is an enlarged fragmentary cross-sectional view taken about the line 4-4 of FIG. 1; and,  
  FIG. 5 is an enlarged fragmentary perspective view showing the blank in the solid position.  
  The bag construction of this invention generally comprises a body portion having a pair of parallel edges defining an opening for the bag. The closure and handle means which incorporate the inventive features are secured at these parallel edges. These closure and handle means comprise a pair of flat cardboard strips of substantial width. These strips each define an opening for receiving the fingers of the user whereby the strips combine to form a handle. The wide flat character of the strips normally maintains the strips in overlying relationship so that a natural closure is provided with access to the bag interior being quite easily accomplished.  
  When making reference to cardboard, it should be understood that paperboard and materials of the same character are included.  
  In the manufacture of the bag, the cardboard strips are first formed from a sheet of carboard by diecutting a one-piece blank. A foldline is provided between the strips, and the strips are preferably held in a one-piece assembly by means of tie points along the foldline. With this arrangement, the assembly can be inserted between the parallel edges of the bag material, and a heat sealing operation will then follow for securing the handle to the bag material.  
  The drawings illustrate a bag 10 characterized by a thermoplastic section 12 and a handle and closure means M. The thermoplastic material may comprise any material conventionally used for this purpose such aspolyethylene.  
  The handle section is formed from a cardboard material with opposing cardboard strips 16 making up this section. Each of these strips defines an opening 18 permitting insertion of the fingers for easy carrying purposes. In the configuration shown in FIG. I, the strips 16 are forced apart whereby the interior of the bag is accessible for the insertion or retrieval of goods.  
  The handle section 14, as illustrated in FIG. 2, is formed from a pair of strips 16 joined along foldline 19. Because the strips are flat, and relatively wide, they will normally assume a flat overlying condition whereby a bag will normally be closed. The illustration of FIG. 2 shows the handle with the strips separated from the bag 12; however, it will be noted that the length of the strips substantially corresponds with the length of the opening defined between the edges 20 of the bag. Accordingly, when the assembly is made, the bag will stretch out flat with the handle portions in overlying relationship unless pulled apart by the user.  
  Handles 2% inches wide and 14 /2 inches long are typically associated with bags having a thermplastic body section 15 inches long and 14% inches wide. With dimensions of this order of magnitude, the handle portions readily assume a flat configuration.  
  As best shown in FIG. 3, the handle sections are initially formed from a one-piece blank 22. This blank may be diecut from a sheet of cardboard with the handle openings 18 being simultaneously formed. The foldline 19 is also formed at this time with the major length of the foldline comprising a slit between the handle sections 16. Short connecting portions 24 interrupt the slits, and these connecting portions therefore serve to hold the handle sections in an assembly.  
  In the manufacture of the bags, the blank assembly 22 is preferably located between the edges 20 of the thermoplastic sheet. The sheet material is then folded over into engagement with the blank for heat sealing of this edge to the opposite handle section. Since the handle section initially overlying the bag material can be simultaneously heat sealed, the assembly operations involved in securing a handle to the bag material become quite simple.  
  The heat sealing operation can be effectively promoted by employing cardboard coated with polyethylene or polyolefins of like character. Although heat sealing is the preferred asse&#39;rnbly procedure, the use of adhesives for securing the cardboard is contemplated.  
  The bag material preferably comes from a roll of material, and the handles may be applied before the elongated sheet is severed transversely to make individual bags. Thus, the handles may be attached at intervals along the length of the folded thermoplastic sheet and thereafter a combined heat sealing and severing blade may be utilized for cutting the sheet into the individual bag sections while at the same time sealing the side edges of each bag.  
  Polyethylene is the preferred material due to its relatively low cost and good heat sealing characteristics. The cardboard may be of any type known to be compatible with the polyethylene for heat sealing purposes.  
  In order to increase the strength and comfort of use of the bag, the handle sections may include a bendable member 26 attached along an edge of one of the openings 18. This member is readily bent through 90 as shown in FIG. 4 to provide an increased contact area for the hand of the user to therefore render the bag more comfortable, particularly when the contents of 5 the bag are relatively heavy. This bendable member 26 is preferably an integral part of the blank 22 with the diecutting operation resulting in severing of this member except in the area of the connecting portion 28.  
  It will be understood that various changes and modifications may be made in the structure described which provide the characteristics of the invention without departing from the spirit thereof, particularly as defined in the following claims.  
 That which is claimed is:  
  1. A method for forming a thermoplastic bag having handle and closure means comprising the steps of diecutting a cardboard blank, cutting slits along a line dividing the blank, said line providing a foldline, said slits including short connecting portions remaining along said foldline to maintain said strip in an assembly, said blank comprising a pair of wide strip portions on opposite sides of said foldline, the folded blank disposing said strip portions in overlying relationship and comprising bottom parallel edges defined by said foldline, said die cutting step also including the die cutting of handle openings into each strip portion, said bag including substantially overlying opposing wall portions with each wall portion defining an upper edge, separating said upper edges and locating said upper edges in contact with respective bottom parallel edges of said strip portions in the area immediately adjacent said foldline, and heat sealing said edges to said strip portions, and including the step of separating said short connecting portions by pulling the strips apart whereby said bag is ready for use.