| 摘要 |
In the art of pigmenting high molecular weight organic materials there is a long-felt need for high-hiding organic red pigments, in particular yellowish red pigments, which are increasingly used to replace the ecologically unsafe inorganic red pigments. However, this gap in the market cannot be satisfactorily filled by using the tetrachloroperylenetetracarboximide pigments known for the aforementioned purpose. According to the invention, it has now been found that a chlorine content of </=25% in such chlorinated perylimides confers remarkable coloristic properties on the pigments thus produced, so that these pigments are superior in hiding powder and masstone to the tetrachloroperylimide compounds described. Accordingly, the invention is directed to high-hiding red pigments of the type of the halogenated perylenetetracarboximides containing up to 4 chlorine atoms, whose chlorine content is 15-25% and which are present as mixed crystal pigments in the beta -modification with an average particle size of ideally >/=0.15 mu m. Perylimide compounds having a higher chlorine content favor the simultaneous formation of the alpha -phase.
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