Use of films of polycondensates
AssigneeBayer Aktiengesellschaft
InventorsVolker Serini, Bernhard Schulte, Claus Burkhardt, Dieter Freitag, Uwe Hucks, Werner Waldenrath, Hans-Leo Weber
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Abstract
Films from aromatic polyesters and from aromatic polyestercarbonates are excellently suitable as electrically insulating films, for example as dielectric for capacitors and as conductor track films.
Claims6
An electrically insulating film comprising a polycondensate containing 75-100 mol-% of bifunctional structural units of the formula (1) and optionally (2) ##STR3## and 25-0 mol-% of bifunctional structural units of the formula (3) and optionally (4) ##STR4## where the acid radicals --CO--R--CO-- in the formulae (1) and (3) denote 75-100 mol-% of tere- and/or isophthalic acid radicals and 25-0 mol-% of radicals of other aromatic dicarboxylic acids and the radicals --O--R.sub.1 --O-- in the formulae (3) and (4) denote radicals of diphenols other than the 2,2-bis(4-hydroxyphenyl)propane radicals contained in formulae (1) and (2), and the molar ratio of ester groups to carbonate groups in the polycondensates is 100/0 to 10/9.
Dependencies are inferred from the claim text.