A separating film with an anti-adhesion layer for preventing an adhesive connection between a thermally curable levelling compound, applied in the region of a joining zone of a first component, and a joining zone of a second component to be joined to the first component. The anti-adhesion layer is provided, at least in parts, with a heating layer. As a result of the actively electrically heatable heating layer of the separating film, which is an integral part of the separating film, the processing time for joining two components, which are subject to tolerances, using a thermally curable levelling compound (known as liquid shimming), can be reduced by at least 40% compared with the conventional process.