Heat sealable polyvinyl chloride films
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.