Claims
- 1. A method for making a multi-layer preform used for plastic blow molding, the method comprising:
- thermoforming a sheet of polyethylene naphthalate to provide an inner layer that functions as a gas barrier; and
- injection molding an outer layer of polyethylene terephthalate around the inner layer of polyethylene naphthalate which limits the transmission of gas through the outer layer of polyethylene terephthalate upon blow molding of the preform into a container.
- 2. A method for making a multi-layer preform used for plastic blow molding as in claim 1 wherein the injection molding of the outer layer is performed with virgin polyethylene terephthalate that has a direct interface with the inner layer of polyethylene naphthalate.
- 3. A method for making a multi-layer preform used for plastic blow molding, the method comprising:
- thermoforming a sheet of polyethylene naphthalate to provide an inner layer that functions as a gas barrier as well as permitting hot filling;
- transferring the thermoformed inner layer of polyethylene naphthalate to an injection mold; and
- injection molding within the injection mold an outer layer of polyethylene terephthalate around the inner layer of polyethylene naphthalate which limits the transmission of gas through the outer layer of polyethylene terephthalate upon blow molding of the preform into a container.
- 4. A method for making a multi-layer preform used for plastic blow molding, the method comprising:
- thermoforming a sheet of polyethylene naphthalate to provide an inner layer that functions as a gas barrier;
- transferring the thermoformed inner layer of polyethylene naphthalate to an injection mold; and
- injection molding within the injection mold an outer layer of virgin polyethylene terephthalate with a direct interface with the inner layer of polyethylene naphthalate which limits the transmission of gas through the outer layer of polyethylene terephthalate upon blow molding of the preform into a container.
Parent Case Info
This is a continuation of application Ser. No. 08/120,038 filed on Sep. 10, 1993 and issued on Aug. 22, 1995 as U.S. Pat. No. 5,443,766.
US Referenced Citations (70)
Foreign Referenced Citations (3)
Number |
Date |
Country |
3107523 |
May 1988 |
JPX |
2211165 |
Jun 1989 |
GBX |
8501472 |
Apr 1985 |
WOX |
Non-Patent Literature Citations (2)
Entry |
Amoco Chemical Company, Bulletin FA-4d "Amoco NDC". |
Derwent World Patent Index Search Polyethylene Naphthalate (PEN). |
Continuations (1)
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Number |
Date |
Country |
Parent |
120038 |
Sep 1993 |
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