An introduction outlining the scope and limitations of this paper is followed by a brief explanation of the essential structural features of metal‐complex dyes.The earliest metal‐complex dyes were produced directly within the fibre material by reacting a metallisable dye with a chromium compound in situ. The first chromium complex dyes prepared in substance, were the chromium complexes containing sulpho‐groups, synthesised by R Bohn of BASF, in 1912, the application of which was first made possible after the discovery by Ciba of a satisfactory dyeing process based on the use of a dyebath made strongly acid with sulphuric acid. These two classes of dye dominated the dyeing industry into the 1950s.At that time 1:2 metal‐complex dyes without sulphonic acid groups but containing nonionic substituents as solubilising groups were introduced. These complexes were applicable from neutral to weakly acid dyebaths, which minimised the damage to the fibres. These dyeings were characterised by high fastness to light and wet treatments. Later, for commercial reasons, sulphonic acid groups were again introduced into the dye molecule to increase their hydrophilic properties. These dyes also have become well established as a result of the introduction of new dyeing methods and the development of dyeing auxiliaries designed to promote level dyeing.In addition to these types of metal‐complex dyes, further metal‐complex dyes selected from the extensive patent literature of the last 50 years because of their interesting structure are described.

Volumen SLVI, Fasciculus I V (1963) -No. 150-151 1369 getrocknct unil cingcclampft. Das crhaltene Rohprodukt liefcrte nach zwcimaligem Umloscn aus Ather-Petrolathcr 42 mg Uion XIV vom Smp. 128-134", clas nach Misch-Smp. und 1R.-Spcktrum mit cinem authentischcn Praparat identisch war. (Die Verbindung enthiclt jcdoch ca. 50/, cles entsprechenden a, B-ungesattigten Ketons.) Bei der Chromatographie des Produktcs an ncutralem Aluminiumoxid (Akt. 11) erfolgte grosstcnteils einc Isomerisierung der Doppelbindung. So konnten nach Umkristallisieren dcr rohen Chromatngrammfraktinnen 10 mg reines 3, 17-Dioxo-d4-19-norandrosten vom Smp. 164-166" gewonnen werden. Dic Verbindung wurde durch Smp., Misch-Smp. und 1R.-Spektrum mit einsm authentischcn Praparat identifiziert.

No abstract

On chroming the dyestuff 1‐amino‐2‐hydroxy‐naphthalene‐4‐sulfonic acid piperidide → 1‐phenyl‐3‐methyl‐5‐pyrazolone, only one 1:2 chromium complex is formed. This fact as well as the absorption spectra and the great stability of the complex indicate that the complex must be coordinated in the Drew‐Pfitzner arrangement, and that the sandwich arrangement must be excluded. Since the steric structure of the 1:2‐complex is already preformed in the adequate 1:1‐complex, our results disprove the conclusions presented by IDELSONet al. [1] [3].