Claims
- 1. A five layer shrink film for high speed packaging lines having a modulus of 50,000 psi or higher and a haze value less than 5.0 comprising:
a first outer high speed polyethylenic layer; a second outer high speed polyethylenic layer; a core cyclic-olefin copolymer containing layer; a first cyclic-olefin copolymer containing intermediate layer between the core cyclic-olefin copolymer containing layer and the first outer high speed polyethylenic layer; and a second cyclic-olefin copolymer containing intermediate layer between the core cyclic-olefin copolymer containing layer and the second outer high speed polyethylenic layer; wherein the high speed ethylenic layers comprise by weight 75% to 95% linear low density polyethylene, from 0% to 15% clyclic-olefin copolymer and from 0% to 10% softening olefin copolymer; wherein the cyclic-olefin copolymer of the five layer shrink film is a single-site catalyzed cyclic-olefin copolymer; wherein softening olefin copolymer comprises by total weight of the five layer shrink film from 2% to 25%; wherein the cyclic-olefin copolymer comprises by total weight of the five layer shrink film from 10% to 30%; and wherein the five layer shrink film comprises less than 1% by weight polystyrene and less than 1% by weight polypropylene.
- 2. The film of claim 1 wherein the linear low density polyethylene copolymer comprises 1 to 10 weight percent 1-octene monomer.
- 3. The film of claim 1 having a thickness between 0.30 and 2.0 mils.
- 4. The film of claim 1 wherein the first high speed polyethylenic layer comprises from 10% to 20% of the total weight of the film; wherein the second high speed polyethylenic layer comprises from 10% to 20% of the total weight of the film; wherein the innermost cyclic-olefin copolymer containing layer comprises from 30% to 60% of the total weight of the film, wherein the first cyclic-olefin copolymer containing intermediate layer comprises from 10% to 20% of the total weight of the film; and wherein the second cyclic-olefin copolymer containing intermediate layer comprises from 10% to 20% of the total weight of the film.
- 5. The film of claim 1 crosslinked using a radiation source.
- 6. The film of claim 5 wherein the radiation source is active on the first collapsed tube of a double-bubble film orientation process.
- 7. The film of claim 5 wherein the radiation source is active on the film subsequent to full biaxial orientation.
- 8. A three layer shrink film for high speed packaging lines having a modulus of 50,000 psi or higher and a haze value less than 5.0 comprising:
a first outer high speed polyethylenic layer; a second outer high speed polyethylenic layer; a core cyclic-olefin copolymer containing layer; wherein the high speed ethylenic layers comprise by weight 75% to 95% linear low density polyethylene, from 0% to 15% cyclic-olefin copolymer and from 0% to 25% softening olefin copolymer; wherein the cyclic-olefin copolymer of the five layer shrink film is a single-site catalyzed cyclic-olefin copolymer; wherein softening olefin copolymer comprises by total weight of the five layer shrink film from 2% to 25%; wherein the cyclic-olefin copolymer comprises by total weight of the five layer shrink film from 10% to 30%; and wherein the five layer shrink film comprises less than 1% by weight polystyrene and less than 1% by weight polypropylene.
- 9. The film of claim 8 wherein the linear low density polyethylene copolymer comprises 1 to 10 weight percent 1-octene monomer.
- 10. The film of claim 8 having a thickness between 0.30 and 2.0 mils.
- 11. The film of claim 8 wherein the first high speed polyethylenic layer comprises from 10% to 20% of the total weight of the film; wherein the second high speed polyethylenic layer comprises from 10% to 20% of the total weight of the film; and wherein the innermost cyclic-olefin copolymer containing layer comprises from 60% to 80% of the total weight of the film.
- 12. The film of claim 8 crosslinked using a radiation source.
- 13. The film of claim 12 wherein the radiation source is active on the first collapsed tube of a double-bubble film orientation process.
- 14. The film of claim 12 wherein the radiation source is active on the film subsequent to full biaxial orientation.
- 15. A method of forming the film of claim 1, the method comprising of:
feeding individual layer compositions into 3 or more separate extruders; extruding the compositions simultaneously into a biaxial film orienting means; and biaxially orienting the film to a thickness of 30 to 200 gauge; wherein a separate extruder extrudes a single homogenous composition.
- 16. The method of claim 15 wherein the biaxial film orienting means consists of a double-bubble film orienting process.
- 17. The method of claim 15 further comprising the step of crosslinking the layers by exposing the layers to radiation dosage.
- 18. The method of claim 17 wherein the radiation dosage is active on the film subsequent to full biaxial orientation.
- 19. The method of claim 16 further comprising the step of crosslinking the layers by exposing the layers to radiation dosage.
- 20. The method of claim 19 wherein the radiation dosage is active on the first collapsed tube of a double-bubble film orientation process.
- 21. A method of forming the film of claim 8, the method comprising of:
feeding individual layer compositions into 2 or more separate extruders; extruding the compositions simultaneously into a biaxial film orienting means; and biaxially orienting the film to a thickness of 30 to 200 gauge; wherein a separate extruder extrudes a single homogenous composition.
- 22. The method of claim 21 wherein the biaxial film orienting means consists of a double-bubble film orienting process.
- 23. The method of claim 21 further comprising the step of crosslinking the layers by exposing the layers to radiation dosage.
- 24. The method of claim 23 wherein the radiation dosage is active on the film subsequent to full biaxial orientation.
- 25. The method of claim 22 further comprising the step of crosslinking the layers by exposing the layers to radiation dosage.
- 26. The method of claim 25 wherein the radiation dosage is active on the first collapsed tube of a double-bubble film orientation process.
CROSS REFERENCE TO OTHER PATENT APPLICATIONS
[0001] This application claims priority under 35 U.S.C. § 119 from U.S. provisional patent application Ser. No. 60/451,236 filed Mar. 3, 2003 and from U.S. provisional patent application Ser. No. 60/473,167 filed May 23, 2003 of the same inventors, which are incorporated by reference in their entirety.
Provisional Applications (2)
|
Number |
Date |
Country |
|
60451236 |
Mar 2003 |
US |
|
60473167 |
May 2003 |
US |