Claims
- 1. A polymer film aged at elevated temperatures of at least about 55.degree. C. for one to fourteen days having good hot tack and a low and broad heat seal temperature range for vertical form and fill film packaging, comprising:
- a propylene or polypropylene-based copolymer or blend as a substrate or core layer; and
- a polymer blend as a surface layer, wherein said polymer blend comprises a butene-1-propylene copolymer having a propylene content of from about 12% by weight to about 30% by weight, a propylene-ethylene copolymer having an ethylene content of from about 2.5% by weight to about 10% by weight, and where said butene-1-propylene copolymer and said propylene-ethylene copolymer are combined in a weight proportion of from about 40:60 to about 75:25 and wherein said polymer film has an acceptable hot tack range of from about 200.degree. F. to about 290.degree. F., and a heat seal temperature range of from about 170.degree. F. to about 290.degree. F.
- 2. A polymer film aged at elevated temperatures of at least about 55.degree. C. for one to fourteen days having good hot tack and a low and broad heat seal temperature range for vertical form and fill film packaging, comprising:
- a propylene or polypropylene-based compolymer or blend as a substrate or core layer; and
- a polymer blend as a surface layer, wherein said polymer blend comprises a butene-1-propylene copolymer having a propylene content from about 15% by weight to about 25% by weight, a propylene-ethylene copolymer having an ethylene content from about 5% by weight to about 7% by weight and wherein said butene-1-propylene copolymer and said propylene-ethylene copolymer are combined in a weight proportion of from about 60:40 to about 70:30 and wherein said polymer film has an acceptable hot tack range of from about 200.degree. F. to about 290.degree. F., and a heat seal temperature range of from about 170.degree. F. to about 290.degree. F.
- 3. A polymer film aged at elevated temperatures of at least about 55.degree. C. for one to fourteen days having good hot tack and a low and broad heat seal temperature range for vertical form and fill film packaging, comprising:
- a polypropylene or propylene-ethylene copolymer as a substrate or core layer; and
- a polymer blend as a surface layer, wherein said polymer blend comprises a butene-1-propylene copolymer having a propylene content of about 20% by weight, a propylene-ethylene copolymer having an ethylene content of about 6% by weight, and where said butene-1-propylene copolymer and said propylene-ethylene copolymer are combined in a weight proportion of about 65:35 and wherein said polymer film has an acceptable hot tack range of from about 200.degree. F. to about 290.degree. F., and a heat seal temperature of from about 170.degree. F. to about 290.degree. F.
Parent Case Info
This is a continuation, of application Ser. No. 655,397, filed Sept. 27, 1984, now abandoned.
US Referenced Citations (6)
Foreign Referenced Citations (1)
Number |
Date |
Country |
0135358 |
Mar 1985 |
EPX |
Continuations (1)
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Number |
Date |
Country |
Parent |
655397 |
Sep 1984 |
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