ABS compositions with improved surface after heat moisture storage

Described herein are polymer compositions comprising at least one inorganic salt comprising a cation selected from the group consisting of alkali metals, alkaline earth metals and aluminium, and an anion selected from the group consisting of chloride, sulfate, nitrate, phosphate, acetate and formate, in a concentration of 100 to 5000 mg/kg, based on the composition, and wherein the salt is present in the composition exclusively in dissolved form or in the form of amorphous and/or crystalline inclusions having a size of not > 60 m. Compositions of the present invention are distinguished by an improved surface after heat-moisture storage and are suitable in particular for the production of mouldings with a high gloss finish that demand a class A surface, which have optionally been subjected, in whole or in part, to a further surface treatment step involving e.g. lacquering, in-mould decoration, or metallization by vacuum deposition or galvanization.