摘要 |
<p>A very thin inner layer composed of a polymer chosen for its barrier and/or inertness properties is fabricated within a container preform constructed mainly from another polymer, or a structure of polymers. The inner layer on the preform is produced either by a controlled coating method involving coating of the injection mold core rod prior to injection molding or by a coating applied directly to the preform after injection molding. This enables both inner and main layers to be brought together at a time when the interface between them is molten. A tie layer can be employed, when desirable, to enable the layers to be combined without melting the layer interface.</p> |