Vertical stand-up pouch with integrated reclose strip

Abstract

A vertical stand-up pouch or flexible package having an integrated reclose strip, and method for manufacturing same, constructed by modification to existing vertical form and fill packaging machines. The modified machine includes a crease-forming mechanism and an apparatus for applying a reclose strip to the sheet of material. The apparatus for applying a reclose strip is incorporated into the mechanism which supplies the continuous sheet of packaging material to the vertical form, fill, and seal machine. The invention involves producing a vertical stand-up pouch having an integrated reclose strip from a single sheet of packaging film by creating a vertical crease along one edge of a packaging film tube prior to forming a transverse seal on the tube. Said vertical crease is formed using a stationary tucker bar positioned outside the packaging film tube and between two forming plates positioned inside the packaging film tube. The reclose strip is attached along the longitudinal axis of the sheet of packaging material prior to forming the sheet into a tube in the conventional manner. The reclose strip includes a peel strip which is removable to allow the package, when opened, to be folded down and sealed against an adhesive which will be exposed upon the removal of the peel strip. In a preferred embodiment, the reclose strip comprises a length of two-sided adhesive tape.

1 . A flexible reclosable stand-up package formed on a form, fill, and seal packaging machine from a continuous sheet of packaging film, said package comprising after formation: 
 a package body having a top end, a bottom end, a front wall, and a back wall disposed between two vertical edge seals, said walls formed from a segment of said sheet of packaging film and having a longitudinal formation axis extending between said vertical edge seals, said bottom end having a crease formed in the packaging material, said film joined to itself at said vertical edge seals and at a back seal extending along said back wall between said vertical seals, said top end, bottom end, crease and back seal being generally parallel with said longitudinal formation axis; and a reclose strip attached to an exterior surface of said back wall and extending between said vertical edge seals, said strip being generally parallel with said longitudinal formation axis and spaced from said top end a distance sufficiently great as to allow the package to be manually folded in a direction from the top toward the strip before the fold engages the strip.    
   
   
       2 . The flexible reclosable stand-up package of  claim 1 , wherein said sheet of packaging film includes a graphics layer which is oriented for viewing by a consumer when said package is stood on its bottom end.  
   
   
       3 . The flexible reclosable stand-up package of  claim 1 , wherein said reclose strip comprises a two-sided length of tape with a first side bonded to said exterior surface of said back wall by a first pressure sensitive adhesive of some strength and a second side of said tape being coated with a second pressure sensitive adhesive having a strength less than the strength of the first adhesive and having the characteristics of bonding to both the tape and the exterior surface of the package and in tension, releasing the package material before releasing the tape such that the second adhesive will remain on the tape when the surface of the package material separates from the second adhesive.  
   
   
       4 . The flexible reclosable stand-up package of  claim 3 , wherein said reclose strip further comprises a peel strip attached to and covering the second adhesive, the second adhesive having the characteristic when in tension of releasing the peel strip prior to releasing the tape.  
   
   
       5 - 8 . (canceled)  
   
   
       9 . A vertical flexible reclosable stand-up package formed by a method comprising the steps of: 
 a) advancing a continuous sheet of packaging film towards said vertical form, fill, and seal machine, wherein said packaging film has lettering oriented perpendicular to the direction of travel of said film;    b) attaching a length of reclose strip to a surface of said advancing sheet of packaging film along the longitudinal axis of said sheet of packaging film, said reclose strip having an adhesive layer facing away from said surface;    c) feeding said packaging film into said vertical form, fill, and seal machine;    d) forming said packaging film into a tube on said vertical form, fill, and seal machine and forming a longitudinal seal, wherein said surface of packaging film having said reclose strip attached thereto is situated on the exterior of said tube;    e) forming a vertical crease in said tube of packaging film prior to sealing said tube traversely;    f) forming a first traverse seal on said tube, said first traverse seal sealing all layers of said tube together, wherein said first traverse seal includes a portion of said vertical crease;    g) dropping a product into the partially formed package created by steps a) through f);    h) forming a second traverse seal on said tube, said second traverse seal sealing all layers of said tube together, wherein said second traverse seal includes a portion of said vertical crease; and    i) severing said package from said tube at said second traverse seal;    wherein said vertical crease is heat-sealed only at said first and second traverse seals.    
   
   
       10 . A vertical form, fill, and seal machine for making a flexible stand-up package having a reclose strip incorporated therein, comprising: 
 a) a mechanism for supplying and advancing a continuous sheet of packaging film towards said vertical form, fill, and seal machine, wherein said packaging film has graphics oriented perpendicular to the direction of travel of said film;    b) an apparatus for attaching a length of reclose strip to a surface of said advancing sheet of packaging film along a longitudinal axis of said sheet of packaging film;    c) a former section for receiving and forming said sheet of packaging film into a tubular shape about a forming/fill tube such that said surface to which the reclose strip is attached is on the exterior of said tubular shape, said forming/fill tube having an entrance portion above said former section and an exit portion below said former section;    d) a heat seal mechanism for forming a back seal on said tubular shape thereby creating a film tube;    e) an apparatus for imparting a crease in said film tube; and    f) a pair of heat sealing jaws for imparting a traverse seal on said film tube, wherein said sealing jaws include a cutting mechanism for severing said package from said tube.    
   
   
       11 . The vertical form, fill, and seal machine of  claim 10 , wherein said attaching apparatus is integral to said supplying and advancing mechanism.  
   
   
       12 . The vertical form, fill, and seal machine of  claim 10 , wherein said length of reclose strip comprises a composite structure which includes a two-sided tape having a first side coated with a first pressure sensitive adhesive of some strength and a second side being coated with a second pressure sensitive adhesive and covered by a peel strip, said first pressure sensitive adhesive having a bonding strength greater than that of said second pressure sensitive adhesive, said second adhesive having the characteristic when in tension, of releasing the peel strip prior to releasing the tape.  
   
   
       13 . The vertical form, fill, and seal machine of  claim 12 , wherein said second pressure sensitive adhesive has the characteristics of bonding to both the tape and the surface of said sheet of packaging film and in tension, and releasing the packaging film before releasing the tape such that the second adhesive will remain on the tape when the surface of the packaging film separates from the second adhesive.  
   
   
       14 . The vertical form, fill, and seal machine of  claim 10 , wherein said attachment apparatus comprises a mechanism for feeding said length of reclose strip adjacent to said surface of said sheet of packaging film as it is advancing, and for positioning and adhering said length of reclose strip to said surface.  
   
   
       15 . The vertical form, fill, and seal machine of  claim 14 , wherein said attachment apparatus comprises a pivoting arm assembly which includes a roller guide mechanism which receives the length of reclose strip from a supply spool and directs it to a stationary bar guide assembly, said bar guide assembly positioning said length of reclose strip a lateral distance across the traverse of said advancing sheet of packaging film and an application roller for bringing said length of reclose strip into contact with said sheet of packaging film.  
   
   
       16 . The vertical form, fill, and seal machine of  claim 15 , wherein said pivoting arm assembly further includes a weight assembly.  
   
   
       17 . The vertical form, fill, and seal machine of  claim 15 , wherein said roller guide mechanism is pivotally attached to said pivoting arm assembly.  
   
   
       18 . The vertical form, fill, and seal machine of  claim 15 , wherein said bar guide assembly may be adjusted to increase or decrease the lateral distance said length of reclose strip is positioned across the traverse of said advancing sheet of packaging material.  
   
   
       19 . The vertical form, fill, and seal machine of  claim 10 , wherein said crease imparting apparatus comprises two forming plates attached to and extending below said forming/fill tube, at least one tension bar attached to and extending below said forming tube at a location approximately opposite from said forming plates; and at least one stationary tucker bar positioned between said forming plates.  
   
   
       20 . The vertical form, fill, and seal machine of  claim 19 , wherein said crease imparting apparatus further comprises a mechanism for blowing a pressurized gas against said packaging film, wherein said gas is blown against the exterior surface of said tube of packaging film at a point between said forming plates, wherein said mechanism for blowing a pressurized gas comprises gas ports in said tucker bar in communication with a pressurized gas source.