Claims
- 1. A process of producing a thermoplastic, heat shrinkable, multilayer film suitable for use in packaging fresh red meats and processed meats, which comprises coextruding a core layer comprising a vinylidene chloride-methyl acrylate copolymer having a vinylidene chloride content of from about 85 to about 95 weight percent and a methyl acrylate content of from about 5 to about 15 weight percent all based on the weight of said copolymer, a first layer adhered directly to one side of said core layer without adhesive material therebetween and comprising very low density polyethylene of density not greater than about 0.915 grams per cubic centimeter, and a second layer adhered directly to the other side of said core layer without adhesive material therebetween and comprising very low density polyethylene of density not greater than about 0.915 grams per cubic centimeter.
- 2. A process according to claim 1 wherein said first layer and said second layer are identical.
- 3. A process according to claim 2 wherein said density is in the range of from about 0.86 to about 0.915 grams per cubic centimeter.
- 4. A process according to claim 1 wherein said very low density polyethylene of said first layer and said very low density polyethylene of said second layer have a melt index in the range of from about 0.5 to about 2.5 decigrams per minute.
- 5. A process according to claim 1 wherein said very low density polyethylene of said first layer and said very low density polyethylene of said second layer have a density of about 0.912 grams per cubic centimeter and a melt index of about 1.0 decigrams per minute.
- 6. A process according to claim 1 wherein said very low density polyethylene of said first layer and said very low density polyethylene of said second layer are copolymers of ethylene and octene-1.
- 7. A process according to claim 1 wherein said core layer comprises vinylidene chloride-methyl acrylate copolymer blended with vinylidene chloride-vinyl chloride copolymer.
- 8. A process according to claim 7 wherein said blend comprises about 75 weight percent vinylidene chloride-methyl acrylate copolymer and about 25 weight percent vinylidene chloride-vinyl chloride copolymer.
- 9. A process according to claim 1 wherein said first layer is a second core layer confined between said first core layer of vinylidene chloride-methyl acrylate copolymer and a coextruded first outer layer comprising a heat sealable thermoplastic polymer.
- 10. A process according to claim 9 wherein said first outer layer comprises a heat sealable thermoplastic polymer selected from the group consisting of an ionomer, an ethylene vinyl acetate copolymer, an ethylene-propylene copolymer, and a propylene blended with another polymer.
- 11. A process according to claim 1 wherein said second layer is a second core layer confined between said first core layer of vinylidene chloride-methyl acrylate copolymer and a coextruded second outer layer comprising a thermoplastic polymer.
- 12. A process according to claim 11 wherein said second outer layer comprises a blend of high density polyethylene with linear low density polyethylene or very low density polyethylene.
- 13. A process according to claim 12 wherein the amount of high density polyethylene in said blend is not greater than about 30 weight percent of the blend.
- 14. A process according to claim 1 wherein said coextrusion is by means of a slot die and said multilayer film is in sheet form.
- 15. A process according to claim 1 wherein said coextrusion is by means of an annular die and said multilayer film is in tubular form.
- 16. A process according to any one of claims 1 through 15 wherein said coextruded multilayer film is biaxially stretched.
- 17. A process according to claim 16 including the step of fabricating said multilayer film into a bag.
RELATED CASES
This is a continuation of application Ser. No. 07/263,947 filed Oct. 28, 1988, now abandoned, which is a continuation of application Ser. No. 07/054,918 filed May 28, 1987 and issued as U.S. Pat. No. 4,863,784.
US Referenced Citations (10)
Non-Patent Literature Citations (3)
Entry |
Plastics Technology, Sep. 1984. |
Plastics Engineering, Sep. 1985. |
"VLDPE: A Breakthrough in Flexible linear Polyethylene", Society of Plastic Engineers Annual Technical Conference (ANTEC) 1985, pp. 463-466. |
Continuations (2)
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Number |
Date |
Country |
Parent |
263947 |
Oct 1988 |
|
Parent |
54918 |
May 1987 |
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