| 摘要 |
<p>The invention relates to a pearlescent pigment comprising a metal oxide-containing, platelet-shaped substrate and having a first and a second protective layer, wherein the metal oxide has a refractive index greater than 1.8, and in which the first protective layer comprises cerium oxide and/or hydrated cerium oxide and/or cerium hydroxide, the second protective layer consists substantially, preferably completely, of SiO2, wherein the second protective layer is disposed on top of the first protective layer, and between the first and second protective layers there can be disposed metal oxide layers which differ from cerium oxide and/or hydrated cerium oxide and/or cerium hydroxide and SiO2, wherein the second protective layer has an organochemical aftercoat and the organochemical aftercoat comprises at least one silane bonded to the second protective layer by means of at least one oxygen atom, saidα-silane having the formula—O(4-n-m)—Si(—R1)m(—CH2—Y)n (I), in which 1≰n+m≰3; m=0 to 2; n=1 to 3 and R1 is a hydrogen atom or an Si—C-bonded C1-C20-hydrocarbon radical or a C1-C15-hydrocarbonoxy radical, in which in each case one or more methylene units not adjacent to one another can be replaced by the groups—O—,—CO—,—COO—,—OCO—, or—OCOO—,—S—, or—NRx—and in which one or more methine units not adjacent to one another can be replaced by the groups—N═,—N═N—, or—P═, wherein R1 can independently be the same or different, Rx can be a hydrogen atom or a linear, branched and/or cyclic C1-C15-hydrocarbon radical or aryl radical, and Y is a functional binding group reactive with a binder system.</p> |
