The present invention relates to a breathable film comprising at least one thermoplastic polymer and a surface-treated filler material product comprising a treatment layer comprising at least one mono-substituted succinic anhydride and/or at least one mono-substituted succinic acid and/or salty reaction product(s) thereof, a process for producing the same, and the use thereof. Furthermore, the present invention is directed to the use of a surface-treated filler material product comprising a treatment layer comprising at least one mono-substituted succinic anhydride and/or at least one mono-substituted succinic acid and/or salty reaction product(s) thereof in breathable films.