The uses of polymer blends comprising: A) 30% to 50% by weight of a biodegradable, aliphatic-aromatic polyester obtainable by condensation of: i) 40 to 70 mol%, based on components i to ii, of one or more dicarboxylic acid derivatives or dicarboxylic acids selected from the group consisting of succinic acid, adipic acid, sebacic acid, azelaic acid and brassylic acid; ii) 60 to 30 mol%, based on components i to ii, of a terephthalic acid derivative; iii) 98 to 102 mol%, based on components i to ii, of a C 2 -C 8 -alkylenediol or C 2 -C 6 -oxyalkylenediol; iv) 0.00% to 2% by weight, based on the total weight of components i to iii, of a chain extender and/or crosslinker selected from the group consisting of a di- or polyfunctional isocyanate, isocyanurate, oxazoline, epoxide, carboxylic anhydride and/or an at least trifunctional alcohol or an at least trifunctional carboxylic acid; v) 0.00% to 50% by weight, based on the total weight of components i to iv, of an organic filler selected from the group consisting of native or plasticized starch, natural fibers, wood flour and/or of an inorganic filler selected from the group consisting of chalk, precipitated calcium carbonate graphite, gypsum, conductivity grade carbon black, iron oxide, calcium chloride, dolomite, kaolin, silicon dioxide (quartz), sodium carbonate, titanium dioxide, silicate, wollastonite, mica, montmorillonites, talcum, glass fibers and mineral fibers; and vi) 0.00% to 2% by weight, based on the total weight of components i to iv, of at least one stabilizer, nucleator, lubricating and release agent, surfactant, wax, antistat, antifoggant, dye, pigment, UV absorber, UV stabilizer or other plastic additive; B) 50% to 70% by weight of polylactic acid and C) 0% to 2% by weight of a compatibilizer, for producing slit film tapes A) 30% to 50% by weight of a biodegradable, aliphatic-aromatic polyester obtainable by condensation of: i) 40 to 70 mol%, based on components i to ii, of one or more dicarboxylic acid derivatives or dicarboxylic acids selected from the group consisting of succinic acid, adipic acid, sebacic acid, azelaic acid and brassylic acid; ii) 60 to 30 mol%, based on components i to ii, of a terephthalic acid derivative; iii) 98 to 102 mol%, based on components i to ii, of a C 2 -C 8 -alkylenediol or C 2 -C 6 -oxyalkylenediol; iv) 0.00% to 2% by weight, based on the total weight of components i to iii, of a chain extender and/or crosslinker selected from the group consisting of a di- or polyfunctional isocyanate, isocyanurate, oxazoline, epoxide, carboxylic anhydride and/or an at least trifunctional alcohol or an at least trifunctional carboxylic acid; v) 0.00% to 50% by weight, based on the total weight of components i to iv, of an organic filler selected from the group consisting of native or plasticized starch, natural fibers, wood flour and/or of an inorganic filler selected from the group consisting of chalk, precipitated calcium carbonate graphite, gypsum, conductivity grade carbon black, iron oxide, calcium chloride, dolomite, kaolin, silicon dioxide (quartz), sodium carbonate, titanium dioxide, silicate, wollastonite, mica, montmorillonites, talcum, glass fibers and mineral fibers; and vi) 0.00% to 2% by weight, based on the total weight of components i to iv, of at least one stabilizer, nucleator, lubricating and release agent, surfactant, wax, antistat, antifoggant, dye, pigment, UV absorber, UV stabilizer or other plastic additive; i) 40 to 70 mol%, based on components i to ii, of one or more dicarboxylic acid derivatives or dicarboxylic acids selected from the group consisting of succinic acid, adipic acid, sebacic acid, azelaic acid and brassylic acid; ii) 60 to 30 mol%, based on components i to ii, of a terephthalic acid derivative; iii) 98 to 102 mol%, based on components i to ii, of a C 2 -C 8 -alkylenediol or C 2 -C 6 -oxyalkylenediol; iv) 0.00% to 2% by weight, based on the total weight of components i to iii, of a chain extender and/or crosslinker selected from the group consisting of a di- or polyfunctional isocyanate, isocyanurate, oxazoline, epoxide, carboxylic anhydride and/or an at least trifunctional alcohol or an at least trifunctional carboxylic acid; v) 0.00% to 50% by weight, based on the total weight of components i to iv, of an organic filler selected from the group consisting of native or plasticized starch, natural fibers, wood flour and/or of an inorganic filler selected from the group consisting of chalk, precipitated calcium carbonate graphite, gypsum, conductivity grade carbon black, iron oxide, calcium chloride, dolomite, kaolin, silicon dioxide (quartz), sodium carbonate, titanium dioxide, silicate, wollastonite, mica, montmorillonites, talcum, glass fibers and mineral fibers; and vi) 0.00% to 2% by weight, based on the total weight of components i to iv, of at least one stabilizer, nucleator, lubricating and release agent, surfactant, wax, antistat, antifoggant, dye, pigment, UV absorber, UV stabilizer or other plastic additive; B) 50% to 70% by weight of polylactic acid and C) 0% to 2% by weight of a compatibilizer, for producing slit film tapes