A process for the production of thermoplastic molding compositions, where an extruder is used which is composed of the following, in the direction of conveying: a) at least one feed zone, where said feed zone preferably comprises at least one dewatering aperture equipped with a metal-wire-mesh composite sheet, a finely perforated metal sheet, or a slit diaphragm, b) at least one squeeze zone which serves to dewater the thermoplastic molding composition, which comprises at least one baffle, and which also comprises in each case at least one associated dewatering aperture, said at least one dewatering aperture being equipped with a metal-wire-mesh composite sheet, a finely perforated metal sheet, or a slit diaphragm, c) at least one input zone, d) at least one plastifying zone provided with mixing, kneading, and/or other plastifying elements, e) at least one vent zone which has at least one vent, where at least one of the vents is preferably equipped with a metal-wire-mesh composite sheet, a finely perforated metal sheet, or a slit diaphragm, and f) a metering zone, where the squeeze zone in the process uses a screw-based extruder in which the outer diameter (Ds) of at least one screw is from 30 mm to 230 mm, in particular from 60 mm to 220 mm, and where the rotation rate of the at least one screw of the extruder is from 60 to 270, in particular 60 to 210 rpm, and where the screw-based extruder used has at least one vent and/or dewatering aperture where there is, secured in the dewatering aperture, at least one metal-wire-mesh composite sheet with two or more layers, there being at least one smaller-mesh layer present on a coarsely woven, large-mesh but mechanically stable backing layer (first layer), where the location of the layer having the smallest mesh is on a side facing toward the product, wherein in the at least one feed zone a thermoplastic molding composition comprising water and/or comprising another vaporizable liquid is introduced by means of feed equipment into the extruder, the thermoplastic molding composition comprises at least one rubber-modified styrene-acrylonitrile copolymer, with at least one acrylate-styrene-acrylonitrile rubber with bimodal particle size distribution and average particle size from 80 nm to 600 nm, preferably from 200 nm to 600 nm, and also with an SAN matrix with AN content from 25% by weight to 35% by weight, preferably from 27% by weight to 33% by weight, and in the input zone other components of the thermoplastic molding composition in the form of melt are introduced into the extruder, and in the vent zone further water or liquids are removed from the thermoplastic molding composition as vapor, and in the metering zone the thermoplastic molding composition is discharged from the extruder. a) at least one feed zone, where said feed zone preferably comprises at least one dewatering aperture equipped with a metal-wire-mesh composite sheet, a finely perforated metal sheet, or a slit diaphragm, b) at least one squeeze zone which serves to dewater the thermoplastic molding composition, which comprises at least one baffle, and which also comprises in each case at least one associated dewatering aperture, said at least one dewatering aperture being equipped with a metal-wire-mesh composite sheet, a finely perforated metal sheet, or a slit diaphragm, c) at least one input zone, d) at least one plastifying zone provided with mixing, kneading, and/or other plastifying elements, e) at least one vent zone which has at least one vent, where at least one of the vents is preferably equipped with a metal-wire-mesh composite sheet, a finely perforated metal sheet, or a slit diaphragm, and f) a metering zone,