A continuous process for preparing pigmented thermoplastic molding compositions in an extruder, comprises I) in a first zone A) metering in from 10 to 99.999% by weight of a thermoplastic polymer into an extruder and II) in a subsequent zone at temperatures below the respective glass transition temperature of the thermoplastic A) B) adding from 0.001 to 60% by weight of a colorant and then heating the thermoplastic/colorant mixture in the subsequent zones, homogenizing the polymer melt and extruding the resultant mixture.
Thermoplastic molding compositions comprising, as substantive components, A) from 5% by weight to (99.99% by weight minus 1 ppb), based on components A) to D), of a polyoxymethylene homo- or copolymer, B) from 1 ppb to 1% by weight, based on the molding composition made from A) to D), of at least one polyethyleneimine homo- or copolymer, C) from 0.01 to 15% by weight of carbon black, and D) from 0 to 80% by weight of other additives, where the total of percentages by weight of components A) to D) is always 100%.
The invention relates to thermoplastic moulding materials containing A) 29 to (100 wt. % minus 1 ppb) of at least one thermoplastic polymer. B) 1 ppb to 1 wt. % or at least one polyethyleneimine homopolymer of copolymer, as well as C) 0 to 70 wt. % of other additives, as the essential constituents thereof. The weight percent of constituents A) to C) amounts to 100% in every case.
