| 摘要 |
A four-layer film for packaging, including blister packaging, is described. Layer 1 may be a rigid film, such as a polyvinyl chloride (PVC) or polyester. Layer 2 may be a moisture barrier, such as polychlorotrifluoroethylene (PCTFE). Layer 3 may be an oxygen barrier, such as a co-extruded film having a polyethylene (PE) layer, an EVOH layer, and a second PE layer. Layer 4 may be a relatively thin layer of a rigid film, such as a PVC or polyester. In this arrangement, Layer 2 may protect the contents of the package from external or atmospheric moisture. Layer 2 may also protect Layer 3 from atmospheric moisture, thereby helping to preserve the effectiveness of Layer 3 as an oxygen barrier. |
