| 摘要 |
<p>Polyamide esters which can be prepared from tetracarboxylic dianhydrides and can be converted into polyimides by alcohol cleavage with cyclization, characterized in that the radicals OR of the ester groups -COOR which are substituted during the polyimide formation are alkoxy radicals having 2 to 5 C atoms which are monosubstituted or polysubstituted by fluorine. Polyimides prepared therefrom are suitable as orientation layers in liquid-crystal display elements and in optical wave guides.</p> |
