Polymeric sheet

摘要

A composite sheet having a thickness in the range from 30 to 400 mu m, has an opaque crystalline polyester first layer having a deformation index of greater than or equal to 2.5%, and a transparent crystalline polyester second layer. The first layer preferably contains titanium dioxide. The composite sheet is suitable for use as a replacement for aluminium foil, being particularly useful as a lid for a container.