Abstract: Thermoplastic molding materials of A) from 72 to 88.5% by weight of a thermoplastic styrene or &agr;-methylstyrene polymer or copolymer, B) from 10 to 20% by weight of a first graft polymer having an average particle diameter d50 from 400 to 600 nm, having an n-butyl acrylate based rubber-elastic graft core, and a styrene or &agr;-methylstyrene (co)polymer graft shell, C) from 1.5 to 8% by weight of a second graft polymer having a bimodal particle size distribution, the average particle diameter d50 being from 25 to 200 nm and from 350 to 550 nm, having a butadiene or isoprene polymer or copolymer based rubber-elastic graft core, and a styrene or &agr;-methylstyrene (co)polymer graft shell, D) from 0 to 50% by weight of conventional additives, where the graft polymers B) and C) constitute from 11.5 to 25% by weight of components A), B) and C), and components A) to D) amount to 100% by weight.