Claims
- 1. A multilayer structure consisting essentially of a first layer consisting of a water insoluble thermoplastic acid functional polymer which is soluble in aqueous alkaline medium and is selected from the group consisting of a copolymer of an alkyl (meth)acrylate and a (meth)acrylic acid, a copolymer of ethylene and acrylic acid, and a copolymer of styrene and maleic anhydride and a second layer consisting of a partially hydrolyzed, thermoplastic polyvinyl alcohol.
- 2. The multilayer structure of claim 1 in which the acid functional polymer is a copolymer of alkyl (meth)acrylates and methacrylic acid.
- 3. The multilayer structure of claim 1 in which the partially hydrolyzed polyvinyl alcohol is 75 to 90 mole % hydrolyzed and has a degree of polymerization in the range of 200 to 2500.
- 4. The multilayer structure of claim 1 further comprising a third layer of a fully hydrolyzed, thermoplastic polyvinyl alcohol.
- 5. The multilayer structure of claim 4 in which the fully hydrolyzed polyvinyl alcohol is 95 to 99+ mole % hydrolyzed and has a degree of polymerization in the range of 200 to 2500.
- 6. A multilayer structure consisting essentially of a first layer consisting of a water insoluble thermoplastic acid functional polymer which is soluble in aqueous alkaline medium and is a copolymer of alkyl (meth)acrylate and (meth)acrylic acid and a second layer consisting of a thermoplastic polyvinyl alcohol which is 75 to 90 mole % hydrolyzed and has a degree of polymerization in the range of 200 to 2500.
- 7. The multilayer structure of claim 6 in which the polyvinyl alcohol is 86 to 89 mole % hydrolyzed.
- 8. The multilayer structure of claim 6 further comprising a third layer of a thermoplastic polyvinyl alcohol which is 95 to 99+ mole % hydrolyzed and has a degree of polymerization In the range of 200 to 2500.
- 9. The multilayer structure of claim 8 in which the polyvinyl alcohol of the third layer is 98 to 99+ mole % hydrolyzed.
- 10. A multilayer structure consisting essentially of a first layer consisting of a water insoluble thermoplastic acid functional polymer which is soluble in aqueous alkaline medium and is a copolymer of alkyl (meth)acrylate and (meth)acrylic acid, a second layer consisting of a thermoplastic polyvinyl alcohol which is 86 to 89 mole % hydrolyzed and has a degree of polymerization in the range of 200 to 2500, and a third layer consisting of a thermoplastic polyvinyl alcohol which is 98 to 99+ mole % hydrolyzed and has a degree of polymerization in the range of 200 to 2500.
- 11. The multilayer structure of claim 1 which is a film.
- 12. The multilayer structure of claim 2 which is a film.
- 13. The multilayer structure of claim 3 which is a film.
- 14. The multilayer structure of claim 4 which is a film.
- 15. The multilayer structure of claim 5 which is a film.
- 16. The multilayer structure of claim 6 which is a film.
- 17. The multilayer structure of claim 7 which is a film.
- 18. The multilayer structure of claim 8 which is a film.
- 19. The multilayer structure of claim 9 which is a film.
- 20. The multilayer structure of claim 10 which is a film.
- 21. A package containing alkaline material and formed from the film of claim 11.
- 22. A package containing alkaline material and formed from the film of claim 12.
- 23. A package containing alkaline material and formed from the film of claim 14.
- 24. A package containing alkaline material and formed from the film of claim 16.
- 25. A package containing alkaline material and formed from the film of claim 18.
- 26. A package containing alkaline material and formed from the film of claim 20.
- 27. The multilayer structure of claim 2 in which the acid functional copolymer is a butyl methacrylate/ethyl acrylate/methacrylic acid terpolymer.
- 28. The multilayer structure of claim 6 in which the acid functional copolymer is a butyl methacrylate/ethyl acrylate/methacrylic acid terpolymer.
- 29. The multilayer structure of claim 10 in which the acid functional copolymer is butyl methacrylate/ethyl acrylate/methacrylic acid terpolymer.
Parent Case Info
This is a continuation of application Ser. No. 07/703,429 filed May 17, 1991 now abandoned.
US Referenced Citations (9)
Foreign Referenced Citations (7)
Number |
Date |
Country |
0284191 |
Apr 1990 |
EPX |
0457600 |
Nov 1991 |
EPX |
62060644 |
Sep 1985 |
JPX |
02108534 |
Apr 1990 |
JPX |
3124734 |
May 1991 |
JPX |
4037539 |
Feb 1992 |
JPX |
1384791 |
May 1992 |
GBX |
Continuations (1)
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Number |
Date |
Country |
Parent |
703429 |
May 1991 |
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