The present invention relates to 1,6,7,12-tetra-(2-isopropylphenoxy)-substituted perylene tetracarboxylic acid diimides of the formula (I) wherein R1 and R2 independently of each other are selected from hydrogen, C1-C24-alkyl, C1-C24-haloalkyl, C3-C24-cycloalkyl, C6-C24-aryl and C6-C24-aryl-C1-C10-alkylene, where the rings of cydoalkyi, aryl, and aryl-alkylene in the three last-mentioned radicals are unsubstituted or substituted as defined in the claims and in the description. Moreover, the present invention relates to the use of said perylene compounds, in particular to the use of said perylene compound(s) in color converters, for data transmission and in security inks for security printing. The present invention also relates to the use of said color converters, to their use in lighting devices, to lighting devices comprising at least one LED and at least said color converter and to a device producing electric power upon illumination comprising a photovoltaic cell and said color converter.