Coated polyester preforms and articles
View Patent ↗This invention relates to articles made of polyester, preferably polyethylene terephthalate (PET), having coated directly to at least one of the surfaces thereof one or more layers of thermoplastic material with good gas-barrier characteristics, and novel methods of making such articles. Preferably the barrier-coated articles take the form of preforms coated by at least one layer of barrier material and the containers blow-molded therefrom. Such barrier-coated containers are preferably of the type to hold beverages such as soft drinks, beer or juice. The preferred barrier materials have a lower permeability to oxygen and carbon dioxide than PET as well as key physical properties similar to PET. The materials and methods provide that the barrier layers have good adherence to PET, even during and after the blow molding process to form containers from preforms. Preferred barrier coating materials include poly(hydroxyamino ethers). In one preferred method, preforms are injection molded then barrier-coated immediately thereafter.
1. A multilayer injection molded preform comprising:
a body portion having a wall portion and an end cap, wherein said body portion comprises
a first innermost layer comprising a thermoplastic polyester; and
a second outermost layer coextensive with and directly bound to the first innermost layer in the wall portion and the end cap and comprising a thermoplastic material selected from the group consisting of (i) phenoxy-type thermoplastic, (ii) copolyester of terephthalic acid, isophthalic acid and at least one diol, and (iii) recycled polyester;
wherein the first innermost is thinner in the end cap than in the wall portion.
2. The injection molded preform of claim 1 , wherein the second layer comprises recycled polyester.
3. The injection molded preform of claim 1 , wherein the wall portion of at least one of the first and second layers transitions to a lower thickness near a support ring.
4. The injection molded preform of claim 1 , wherein the first layer comprises polyethylene terephthalate.
5. The injection molded preform of claim 1 , wherein the second layer consists of a plurality of microlayers comprising barrier material.
6. The injection molded preform of claim 1 , wherein the second layer has a thickness of about 0.01-5.0 mm.
7. The injection molded preform of claim 1 , wherein at least one of said first and second layers comprises a barrier material.
8. The injection molded preform of claim 7 , wherein the barrier material further comprises Nanoparticles.
9. The injection molded preform of claim 7 , wherein the barrier material comprises poly(hydroxyamino ether).
10. The injection molded preform of claim 9 , wherein the barrier material further comprises one or more resorcinol derivatives.
11. The injection molded preform of claim 10 , wherein the resorcinol derivative comprises resorcinol diglycidyl ether.
12. The injection molded preform of claim 7 , wherein the barrier material comprises a copolyester of terephthalic acid, isophthalic acid and at least one diol, wherein the at least one diol comprises ethylene glycol.
13. A multilayer injection molded preform comprising:
a body portion having a wall portion and an end cap, wherein said body portion comprises
a first layer comprising a thermoplastic polyester; and
a second layer coextensive with and directly bound to the first layer in the wall portion and the end cap and comprising a thermoplastic material selected from the group consisting of (i) phenoxy-type thermoplastic, (ii) copolyester of terephthalic acid, isophthalic acid and at least one diol, and (iii) recycled polyester;
wherein the first layer is thinner in the end cap than in the wall portion and the second layer is thinner in the wall portion than in the end cap; and
wherein the first layer extends longitudinally above the second layer and terminates above a support ring in a single layer neck finish section, and the second layer terminates below the support ring.
14. An injection molded preform comprising:
a body comprising wall and end cap portions, wherein the body is formed from at least a first and second layer, said first and second layers being coextensive through the wall and end cap portions and directly bound together,
said first layer comprising a thermoplastic polyester; and
said second layer comprising an amorphous thermoplastic material having barrier properties;
wherein one of said first and second layers is thinner in the end cap than in the wall portion so as to facilitate the rapid removal of said layer from a mold following injection; and
wherein the first layer extends longitudinally above the second layer and terminates above a support ring in a single layer neck finish section, and the second layer terminates below the support ring.
15. The injection molded preform of claim 14 , wherein the second layer further comprises Nanoparticles.
16. The injection molded preform of claim 14 , wherein the wall portion of at least one of the first and second layers transitions to a lower thickness near a support ring.
17. The injection molded preform of claim 14 wherein the first layer is the innermost layer of the preform.
18. The injection molded preform of claim 14 , further comprising a third layer directly bound to the second layer.
19. The injection molded preform of claim 14 , wherein the first layer comprises polyethylene terephthalate.
20. The injection molded preform of claim 14 , wherein the amorphous thermoplastic material of the second layer is phenoxy-type thermoplastic or a copolyester of terephthalic acid, isophthalic acid and at least one diol.
21. The injection molded preform of claim 20 , wherein the second layer comprises poly(hydroxyamino ether).
22. The injection molded preform of claim 21 , wherein the poly(hydroxyamino ether) further comprises one or more resorcinol derivatives.
23. The injection molded preform of claim 22 , wherein the resorcinol derivative comprises resorcinol diglycidyl ether.
24. The injection molded preform of claim 20 , wherein the second layer comprises a copolyester of terephthalic acid, isophthalic acid and at least one diol, wherein the at least one diol comprises ethylene glycol.
25. A multilayer injection molded preform comprising:
a body portion having a wall portion and an end cap, wherein said body portion comprises
a first layer comprising a thermoplastic polyester;
a second layer coextensive with and directly bound to the first layer in the wall portion and the end cap and comprising recycled polyester;
a third layer directly bound to the second layer and comprising a barrier material;
wherein one of the first or second layers is thinner in the end cap than in the wall portion; and
wherein the first layer extends longitudinally above the second layer and terminates above a support ring in a single layer neck finish section, and the second layer terminates below the support ring.
26. The injection molded preform of claim 25 , wherein the barrier material comprises poly(hydroxyamino ether).
27. The injection molded preform of claim 25 , wherein the barrier material comprises a copolyester of terephthalic acid, isophthalic acid and at least one diol, wherein the at least one diol comprises ethylene glycol.
28. The injection molded preform of claim 25 , wherein the wall portion of at least one of the first, second, or third layers transitions to a lower thickness near a support ring.
29. The injection molded preform of claim 25 , wherein the first layer comprises polyethylene terephthalate.
30. The injection molded preform of claim 25 , further comprising a fourth layer directly bound to the third layer.
31. The injection molded preform of claim 25 , wherein the second layer has a thickness of about 0.01-5.0 mm.
32. The injection molded preform of claim 25 , wherein the barrier material further comprises one or more resorcinol derivatives.
33. The injection molded preform of claim 32 , wherein the resorcinol derivative comprises resorcinol diglycidyl ether.
34. A multilayer injection molded preform comprising:
a body portion having a wall portion and an end cap, wherein said body portion comprises
a first layer comprising polyethylene terephthalate;
a second layer coextensive with and directly bound to the first layer in the wall portion and the end cap and comprising recycled polyethylene terephthalate;
a third layer directly bound to the second layer and comprising poly(hydroxyamino ether);
wherein the one of the first or second layers is thinner in the end cap than in the wall portion; and
wherein the first layer extends longitudinally above the second layer and terminates above a support ring in a single layer neck finish section, and the second layer terminates below the support ring.
35. The injection molded preform of claim 34 , wherein the wall portion of at least one of the first, second, or third layers transitions to a lower thickness near a support ring.
36. The injection molded preform of claim 34 , wherein the first layer is the innermost layer.
37. The injection molded preform of claim 34 , wherein the second layer has a thickness of about 0.01-5.0 mm.
38. The injection molded preform of claim 34 , wherein the poly(hydroxyamino ether) further comprises one or more resorcinol derivatives.
39. The injection molded preform of claim 38 , wherein the resorcinol derivative comprises resorcinol diglycidyl ether.