The present invention relates in a first embodiment to a polymer film comprising a propylene random copolymer with a total comonomer content of 4.5 to 12 mol % wherein the sealing initiation temperature SIT of the film is Tm−30° C. or less, preferably Tm−33° C. or less, in a second embodiment to a polymer film comprising a propylene random copolymer with a total comonomer content of 4.5 to 12 mol % wherein the film is having a relative reduction of the static friction value (inside-inside) from one to four days of 35% or more, preferably 40% or more, in a third embodiment to a polymer film comprising a propylene random copolymer with a total comonomer content of 4.5 to 12 mol % wherein the distribution of the comonomer in the random copolymer determined according to TREF method is multimodal, preferably bimodal, in a fourth embodiment to a polymer film comprising a propylene random copolymer with a total comonomer content of 4.5 to 12 mol %, wherein the copolymer is having an elution interval of 50° C. or more, and in a fifth embodiment to a polymer film comprising a copolymer with a total comonomer content of 4.5 to 12 mol % wherein the random copolymer is a unimodal polymer and the elution interval is determined by the equation Y≦4.5·m+16 wherein Y is the elution interval in ° C. and m is the percentage of ethylene in the copolymer in wt. %.