| abstract |
1:2 chromium complex dyes of the formulain whichR signifies C1-9-alkyl or a radical of the formulaR1 signifies C1-4-alkyl, -COOM, -COOR5 or -CONH2,R2 signifies hydrogen or -SO3M,R3 signifies hydrogen, methyl or methoxy,R4 signifies hydrogen, methyl, methoxy or chloro,n signifies from 0 to 3,M signifies hydrogen or a non-chromophoric cation andKat+ signifies hydrogen or a non-chromophoric cationare suitable for dyeing artificially produced oxide layers on aluminium or aluminium alloys and so give highly lightfast dyeings in orange shades. |