Use of a surface-reacted calcium carbonate or a combination of surface reacted calcium carbonate and mineral material selected from the group comprising mineral pigments and/or fillers as an anti-blocking agent in polymer(s) containing compositions, wherein - the surface-reacted calcium carbonate is a reaction product of natural ground or precipitated calcium carbonate with carbon dioxide and one or more H 3 O + ion donors in an aqueous medium, wherein the carbon dioxide is formed in situ by the H 3 O + ion donor treatment and/or is supplied from an external source; and wherein - the surface reacted calcium carbonate or the combination of surface reacted calcium carbonate and mineral material is added to polymer(s) containing compositions, - wherein the polymer(s) are selected from aqueous polymer dispersions comprising at least one copolymer obtainable by emulsion polymerisation of (a) one or more principal monomers selected from the group consisting of C 1 -C 4 alkyl (meth)acrylates, (b) 0.1 to 5 wt% of one or more acid monomers, (c) 0 to 20 wt% of acrylonitrile and (d) 0 to 10 wt% of further monomers other than the monomers (a) to (c), - wherein the glass transition temperature of the copolymer is in the range from 10 to 45°C determined by differential scanning calorimetry (ASTM E1356), - wherein the emulsion polymerization is carried out in an aqueous medium in the presence of at least one carbohydrate compound, and wherein - the surface reacted calcium carbonate or the combination of surface reacted calcium carbonate and mineral material is present in the polymer(s) comprising composition in a weight based ratio of surface reacted calcium carbonate or the combination of surface reacted calcium carbonate and mineral material to polymer(s) of 1: 9 to 4: 1. - the surface-reacted calcium carbonate is a reaction product of natural ground or precipitated calcium carbonate with carbon dioxide and one or more H 3 O + ion donors in an aqueous medium, wherein the carbon dioxide is formed in situ by the H 3 O + ion donor treatment and/or is supplied from an external source; and wherein - the surface reacted calcium carbonate or the combination of surface reacted calcium carbonate and mineral material is added to polymer(s) containing compositions, - wherein the polymer(s) are selected from aqueous polymer dispersions comprising at least one copolymer obtainable by emulsion polymerisation of (a) one or more principal monomers selected from the group consisting of C 1 -C 4 alkyl (meth)acrylates, (b) 0.1 to 5 wt% of one or more acid monomers, (c) 0 to 20 wt% of acrylonitrile and (d) 0 to 10 wt% of further monomers other than the monomers (a) to (c), - wherein the glass transition temperature of the copolymer is in the range from 10 to 45°C determined by differential scanning calorimetry (ASTM E1356), - wherein the emulsion polymerization is carried out in an aqueous medium in the presence of at least one carbohydrate compound, and wherein - wherein the polymer(s) are selected from aqueous polymer dispersions comprising at least one copolymer obtainable by emulsion polymerisation of (a) one or more principal monomers selected from the group consisting of C 1 -C 4 alkyl (meth)acrylates, (b) 0.1 to 5 wt% of one or more acid monomers, (c) 0 to 20 wt% of acrylonitrile and (d) 0 to 10 wt% of further monomers other than the monomers (a) to (c), (a) one or more principal monomers selected from the group consisting of C 1 -C 4 alkyl (meth)acrylates, (b) 0.1 to 5 wt% of one or more acid monomers, (c) 0 to 20 wt% of acrylonitrile and (d) 0 to 10 wt% of further monomers other than the monomers (a) to (c), - wherein the glass transition temperature of the copolymer is in the range from 10 to 45°C determined by differential scanning calorimetry (ASTM E1356), - wherein the emulsion polymerization is carried out in an aqueous medium in the presence of at least one carbohydrate compound, and wherein - the surface reacted calcium carbonate or the combination of surface reacted calcium carbonate and mineral material is present in the polymer(s) comprising composition in a weight based ratio of surface reacted calcium carbonate or the combination of surface reacted calcium carbonate and mineral material to polymer(s) of 1: 9 to 4: 1.