Abstract: Multilayer pearlescent pigments comprising platelet-shaped transparent substrates provided with an optically active coating, where the coating includes at least (a) a nonabsorbing high-index layer A having a refractive index n?1.8, (b) a low-index layer B having a refractive index n<1.8, (c) a nonabsorbing high-index layer C having a refractive index n?1.8 and also (d) optionally at least one outer protective layer D where the pigments have a cumulative frequency distribution of a volume-averaged size distribution function, with the indices D10, D50, D90 and a span ?D in a range from 0.7-1.4, the span ?D being calculated in accordance with formula (I) ?D=(D90?D10)/D50??(I). The disclosure further relates to a method for producing these multilayer pearlescent pigments, and also to their use.

Abstract: Multilayer pearlescent pigments with a silver interference color, based on platelet-shaped transparent substrates with an optically active coating, where the optically active coating includes at least a) a high-index layer A having a refractive index n?1.8 b) a low-index layer B having a refractive index n<1.8 c) a high-index layer C having a refractive index n?1.8 and also d) optionally an outer protective layer D. The multilayer pearlescent pigments have the indices D10, D50, D90 from the cumulative frequency distribution of the volume-averaged size distribution function, with a span ?D of 0.7-1.4, the span ?D being calculated in accordance with the formula ?D=(D90?D10)/D50. The invention further relates to a method for producing these multilayer pearlescent pigments, and also to their use.

Abstract: Pearlescent pigments including a largely transparent platelet-shaped substrate having a density ?S and at least one optically active coating having a density ?M, the substrate having an average size d50 of 3 to 8 ?m and an average height hS of 40 to 110 nm. The disclosure further relates to a method for producing the pearlescent pigments, and also to the use thereof.

Abstract: The invention relates to effect pigments having an aluminum core or aluminum alloy core and an aluminum oxide-containing or aluminum oxide/hydroxide-containing layer enveloping said aluminum core or aluminum alloy core, obtained by chemical wet-process oxidation of lamellar aluminum pigments or aluminum alloy pigments, the content of metallic aluminum in the aluminum core or aluminum alloy core being not more than 90% by weight, based on the total weight of the pigment, wherein the oxidized aluminum pigments or aluminum alloy pigments exhibit at least one highly refractive metal chalcogenide layer having a refractive index of >1.95, and a mixed layer is formed between the highly refractive metal chalcogenide layer and the enveloping aluminum oxide-containing or aluminum oxide/hydroxide-containing layer. The invention further relates to a process for the production of such effect pigments and to the use thereof.

Abstract: The invention relates to an IR radiation-reflecting pigment comprising a platelet-shaped, metallic, IR-reflecting core, the IR radiation-reflecting core being provided with a substantially enveloping coating whose absorption for IR radiation is substantially low, and the IR-reflecting pigment being substantially dark. The invention further relates to a method of producing these pigments and also to the use thereof.

Abstract: The invention relates to a process for roughening metal surfaces to improve adhesion of layers which are thermally sprayed thereon, in that in a first process step recesses or depressions (2) are introduced into the surface in a material-detaching or material-removing treatment so that the protruding metal of the surface forms raised microstructures (3), in particular projections, ridges, protuberances or bumps, these microstructures being reworked in at least a second process step by shaping and/or breaking so that a significant proportion of the structures form undercuts (4) in relation to the surface.