High-Clarity, Cast Polypropylene Produce Pouch and Method

Abstract

A high-clarity, cast polypropylene produce pouch with first and second sidewalls and a bottom panel joined to form a pouch wherein the first and second sidewalls and the bottom panel are formed from cast polypropylene. The bottom panel can be a bottom gusset panel. The first and second sidewalls and the bottom gusset panel can have edges joined by side welding or heat sealing. Zipper or slide closures can close the first and second sidewalls. A method for forming a high-clarity, cast polypropylene produce pouch comprises creating a polypropylene (PP) resin, passing the polypropylene (PP) resin through a cast extruding machine and extruding molten polypropylene (PP) to produced extruded polypropylene (PP), rolling the extruded polypropylene (PP) in a cooling roller, and applying a surface-modifying corona treatment to the extruded polypropylene (PP).

1 . A high-clarity, cast polypropylene (PP) produce pouch comprising:
 a pouch with first and second sidewalls wherein the first and second sidewalls have edges that joined to form a pouch;   wherein the first and second sidewalls are formed from cast polypropylene (PP) film.   
     
     
         2 . The high-clarity, cast polypropylene (PP) produce pouch of  claim 1  further comprising a bottom gusset panel joined to the first and second sidewalls. 
     
     
         3 . The high-clarity, cast polypropylene (PP) produce pouch of  claim 2  wherein the first and second sidewalls and the bottom gusset panel have edges that are joined by side welding. 
     
     
         4 . The high-clarity, cast polypropylene (PP) produce pouch of  claim 2  wherein the first and second sidewalls and the bottom gusset panel have edges that are joined by heat sealing. 
     
     
         5 . The high-clarity, cast polypropylene (PP) produce pouch of  claim 1  wherein the produce pouch has a mouth defined by edges of the first and second sidewalls and further comprising a closure mechanism for selectively joining the first and second sidewalls to close the mouth. 
     
     
         6 . The high-clarity, cast polypropylene (PP) produce pouch of  claim 5  wherein the closure mechanism comprises a zipper closure. 
     
     
         7 . The high-clarity, cast polypropylene (PP) produce pouch of  claim 5  wherein the closure mechanism comprises a slide closure and a slider for adjusting the slide closure between open and closed configurations. 
     
     
         8 . (canceled) 
     
     
         9 . The high-clarity, cast polypropylene (PP) produce pouch of  claim 2  wherein each of the first and second sidewalls has a body portion with a rectangular upper section and a tapered lower section and wherein the bottom gusset panel has a rectangular main section and pointed ends that taper at angles corresponding to the tapered lower sections of the first and second sidewalls whereby, when the produce pouch is in an open configuration, the bottom gusset panel establishes a foot for enabling the produce pouch to be disposed in a free-standing position. 
     
     
         10 . The high-clarity, cast polypropylene (PP) produce pouch of  claim 1  further comprising a plurality of through-holes in each of the first and second sidewalls. 
     
     
         11 . The high-clarity, cast polypropylene (PP) produce pouch of  claim 2  further comprising a handle formed by handle portions disposed through the first and second sidewalls. 
     
     
         12 . The high-clarity, cast polypropylene (PP) produce pouch of  claim 11  wherein the produce pouch has a mouth defined by edges of the first and second sidewalls and further comprising a closure mechanism for selectively joining the first and second sidewalls to close the mouth wherein the handle is disposed proximal to the closure mechanism relative to the bottom gusset panel. 
     
     
         13 . The high-clarity, cast polypropylene (PP) produce pouch of  claim 11  wherein the produce pouch has a mouth defined by edges of the first and second sidewalls and further comprising a closure mechanism for selectively joining the first and second sidewalls to close the mouth wherein the handle is disposed distal to the closure mechanism relative to the bottom gusset panel. 
     
     
         14 . A method for forming a high-clarity, cast polypropylene (PP) produce pouch with first and second sidewalls formed from cast polypropylene (PP) film, the method comprising the following steps:
 providing a molten polypropylene (PP) resin blend;   passing the molten polypropylene (PP) resin blend through a cast extruding machine and extruding the molten polypropylene (PP) resin blend to produce extruded polypropylene (PP);   rolling the extruded polypropylene (PP) in a cooling roller;   providing a curing time;   slitting the extruded polypropylene (PP); and   joining portions of the extruded polypropylene (PP) to form a cast polypropylene (PP) produce pouch with first and second sidewalls.   
     
     
         15 . The method for forming a high-clarity, cast polypropylene (PP) produce pouch of  claim 14  wherein the step of passing the polypropylene (PP) resin blend through a cast extruding machine is carried out at a temperature of 225-235° C. (or 437-455° F.). 
     
     
         16 . The method for forming a high-clarity, cast polypropylene (PP) produce pouch of  claim 14  further comprising applying a surface-modifying corona treatment to the extruded polypropylene (PP). 
     
     
         17 . The method for forming a high-clarity, cast polypropylene (PP) produce pouch of  claim 14  wherein the polypropylene (PP) resin blend includes an anti-blocking agent. 
     
     
         18 . The method for forming a high-clarity, cast polypropylene (PP) produce pouch of  claim 14  wherein the polypropylene (PP) resin blend includes a slipping agent 
     
     
         19 . The method for forming a high-clarity, cast polypropylene (PP) produce pouch of  claim 14  wherein the polypropylene (PP) resin blend includes an antistatic agent. 
     
     
         20 . The method for forming a high-clarity, cast polypropylene (PP) produce pouch of  claim 14  wherein the polypropylene (PP) resin blend includes a nucleating agent. 
     
     
         21 . The method for forming a high-clarity, cast polypropylene (PP) produce pouch of  claim 14  therein the polypropylene (PP) resin blend includes a propylene carrier elastomer. 
     
     
         22 . The method for forming a high-clarity, cast polypropylene (PP) produce pouch of  claim 14  further comprising the step of rolling the extruded polypropylene (PP) in a secondary cooling roller. 
     
     
         23 . The method for forming a high-clarity, cast polypropylene (PP) produce pouch of  claim 14  wherein the step of joining portions of the extruded polypropylene (PP) to form a cast polypropylene (PP) produce pouch with first and second sidewalls comprises heat sealing the portions of extruded polypropylene (PP). 
     
     
         24 . The method for forming a high-clarity, cast polypropylene (PP) produce pouch of  claim 14  wherein the step of joining portions of the extruded polypropylene (PP) to form a cast polypropylene (PP) produce pouch with first and second sidewalls comprises side welding the portions of extruded polypropylene (PP). 
     
     
         25 . The method for forming a high-clarity, cast polypropylene (PP) produce pouch of  claim 14  wherein the step of providing a curing time comprises providing an approximately 72-hour curing time.