Heat sealable polyvinyl chloride films

Abstract

A heat sealable film for use in food packaging comprises a resin composition comprising vinyl chloride homopolymer, vinyl chloride-vinyl acetate copolymer and plasticizer in an amount greater than about 15% by weight of the resin composition. In one embodiment, the film is adapted to provide a controlled oxygen transmission of at least 500 cc/in 2 /24 hours. The embodiment is also adapted to heat seal on conventional packaging equipment.

1 . A heat sealable film for use in food packaging comprising: 
 at least one extruded film formed from a resin composition comprising a blend of (a) polyvinyl chloride; (b) copolymer of vinyl chloride and vinyl acetate; and (c) plasticizer, wherein the plasticizer is present in an amount greater than about 15% by weight of the resin composition; and    wherein the extruded film is adapted to heat seal to itself.    
     
     
         2 . The heat sealable film of  claim 1 , wherein the plasticizer is present in an amount greater than about 20% by weight of the resin composition.  
     
     
         3 . The heat sealable film of  claim 1 , wherein the plasticizer is present in an amount ranging from about 15% to about 40% by weight of the resin composition.  
     
     
         4 . The heat sealable film of  claim 1 , wherein the plasticizer is present in an amount ranging from about 15% to about 30% by weight of the resin composition.  
     
     
         5 . The heat sealable film of  claim 1 , wherein the film comprises copolymer of vinyl chloride and vinyl acetate in an amount ranging from about 1% to about 30% by weight of the resin composition.  
     
     
         6 . The heat sealable film of  claim 1 , wherein the film comprises copolymer of vinyl chloride and vinyl acetate in an amount ranging from about 5% to about 20% by weight of the resin composition.  
     
     
         7 . The heat sealable film of  claim 1 , wherein the film comprises copolymer of vinyl chloride and vinyl acetate in an amount ranging from about 10% to about 20% by weight of the resin composition.  
     
     
         8 . The heat sealable film of  claim 1 , wherein the film comprises copolymer of vinyl chloride and vinyl acetate in an amount ranging from about 15% to about 20% by weight of the resin composition.  
     
     
         9 . The heat sealable film of  claim 1 , wherein the film is oriented biaxially in an amount ranging from about 50% to about 400% of its original length in the machine direction and in the transverse direction.  
     
     
         10 . The heat sealable film of  claim 1 , wherein the film has a heat sealing window of at least 20° F.  
     
     
         11 . The heat sealable film of  claim 1 , wherein the film has a heat sealing window of at least 30° F.  
     
     
         12 . The heat sealable film of  claim 1 , wherein the film is an irradiated film having crosslinked polymers.  
     
     
         13 . The heat sealable film of  claim 1 , wherein the film has an oxygen transmission rate of about 150 to about 1200 g/100 in 2 /24 hours.  
     
     
         14 . The heat sealable film of  claim 1 , wherein the film comprises slip in an amount ranging from about 0.05% to about 0.6% by weight of the resin composition.  
     
     
         15 . The heat sealable film of  claim 1 , wherein the film comprises slip in an amount ranging from about 0.01% to about 0.6% by weight of the resin composition.  
     
     
         16 . A heat sealable film for use in food packaging comprising: 
 at least one extruded film formed from a resin composition comprising a blend of:    polyvinyl chloride;    copolymer of vinyl chloride and vinyl acetate in an amount ranging from about 1.5% to about 30% by weight of the resin composition; and    plasticizer in an amount greater than about 15% by weight of the resin composition; and    wherein the extruded film is adapted to heat seal to itself.    
     
     
         17 . The heat sealable film of  claim 16 , wherein the plasticizer is present in an amount ranging from about 15% to about 40% by weight of the resin composition.  
     
     
         18 . The heat sealable film of  claim 16 , wherein the film has an oxygen transmission rate of about 150 to about 1200 g/100 in  2 /24 hours.  
     
     
         19 . The heat sealable film of  claim 16 , wherein the film has a heat sealing window of at least 20° F.  
     
     
         20 . A heat sealable film for use in food packaging comprising: 
 at least one extruded film formed from a resin composition comprising a blend of (a) polyvinyl chloride; (b) copolymer of vinyl chloride and vinyl acetate; and (c) plasticizer, wherein the plasticizer is present in an amount greater than about 15% by weight of the resin composition;    wherein the extruded film has an oxygen transmission rate of about 150 g/100 in 2 /24 hours to about 1200 g/100 in 2 /24 hours; and    wherein the extruded film has a heat sealing window of at least 20° F.