| abstract |
The use of a heat-stabilised, heat-set oriented film comprising poly(ethylene naphthalate) as a substrate in, or in the manufacture of, an electronic or opto-electronic device containing a conjugated conductive polymer, wherein said film has a shrinkage at 30 mins at 230 °C of less than 1 %; and a composite film comprising such a substrate layer and on a surface thereof a barrier layer. |