MULTILAYER CONTAINERS AND PREFORMS HAVING BARRIER PROPERTIES
Preferred embodiments relate to methods and apparatus for making articles made of polyester, preferably virgin polyethylene terephthalate (PET), having coated directly to at least one of the surfaces thereof one or more layers of recycled or post-consumer PET and one or more layers of a material with good gas-barrier characteristics, preferably silicon oxide. Preferably, the recycled PET layer comprises about 25% to about 50% of the entire material content. Preferably the articles take the form of preforms and the containers are blow-molded therefrom and the barrier layer is subsequently applied. The preferred barrier materials have a lower permeability to oxygen and carbon dioxide than PET. In addition, the neck of the preforms and bottles is at least partially in the crystalline state and the body is primarily in the amorphous or semi-crystalline state. This structure in a preform enables the preform to be easily blow molded by virtue of the amorphous material in the body, while being able to have dimensional stability in hot-fill applications.
1 . An article comprising:
a substrate layer comprising polyester;
a first barrier layer deposited on the substrate layer, the barrier layer comprising silicon oxide; and
a second barrier layer comprising a Phenoxy-type Thermoplastic material.
2 . The article of claim 1 , wherein the Phenoxy-type Thermoplastic comprises a polyhydroxyaminoether barrier material.
3 . The article of claim 2 , wherein the Phenoxy-type thermoplastic comprises a derivative of resorcinol.
4 . The article of claim 3 , wherein the derivative of resorcinol is resorcinol diglycidyl ether.
5 . The article of claim 1 , wherein the barrier layer deposited on the substrate layer is deposited on the inside of the article.
6 . The article of claim 1 , wherein the polyester comprises polyethylene terephthalate.
7 . The article of claim 1 , wherein the article is a preform.
8 . An article comprising:
a substrate layer comprising polyester;
a first barrier layer disposed between a substrate layer and a second barrier layer, the first barrier layer comprising silicon oxide; and
wherein the second barrier layer has a lower permeability to oxygen and carbon dioxide than the polyester.
9 . The article of claim 8 , wherein the second barrier layer comprises a Phenoxy-type thermoplastic.
10 . The article of claim 9 , wherein the Phenoxy-type Thermoplastic comprises a polyhydroxyaminoether barrier material.
11 . The article of claim 10 , wherein the Phenoxy-type thermoplastic comprises a derivative of resorcinol.
12 . The article of claim 8 , wherein the article comprises a neck portion and a body portion, the neck portion being made of only the substrate layer.
13 . The article of claim 8 , wherein the second barrier layer is an overmolded barrier layer.
14 . The article of claim 8 , wherein the first barrier layer is coextensive with and directly bound to the substrate layer in a body portion of the article.
15 . The article of claim 8 , wherein the article further comprises a layer of recycled polyester.
16 . The article of claim 8 , wherein the article is a preform.
17 . A method of coating a plastic coated article, the method comprising:
providing an article comprising polyester, the article having an exterior surface and an interior surface;
coating at least one of the exterior surface or the interior surface with a silicon oxide barrier film; and
coating the exterior surface of the article with a gas barrier material having a lower permeability to oxygen and carbon dioxide than the polyester.
18 . The method of claim 17 , wherein the gas barrier material is a phenoxy-type thermoplastic.
19 . The method of claim 17 , wherein the gas barrier material is a polyhydroxyaminoether.
20 . The method of claim 17 , wherein the step of coating comprises depositing the silicon oxide barrier film by plasma enhanced chemical vapor deposition.