Flexible insulating sheets are employed in electrical machines for layer insulation, slot insulation and interphase insulation. As a result of the general trend towards performance increase these materials are submitted to high electrical and thermal stresses. Good mechanical strength is the prerequisite for automatic processing by the customer.
These demands are met in particular by combined flexible insulating materials in multi-layer structures of pressboard, polyester and polyimide foils, of aramide papers and various non-woven fabrics.