White, biaxially oriented polyester films which have a base layer B which comprises a thermoplastic polyester such as polyethylene terephthalate, and which comprise substantially only TiO.sub.2 as a white pigment, whose R value is less than 43 daN/mm.sup.2, whose e.sub.max ratio is less than 2.5 and at least one of whose two surfaces of the film has been provided with an acrylate-containing coating, are particularly tear-resistant and do not tend to delamination and are therefore suitable in particular as lid films for food containers, for example yoghurt cups. A process is described for producing the films.