253,488. I. G. Farbenindustrie Akt.- Ges., (Assignees of Akt.-Ges. f³r Anilin Fabrikation). June 9, 1925, [Convention date]. Azo dyes ; lakes; azine derivatives.-Azo dyes are made by coupling a diazo-compound with an oxyazine produced by alkaline fusion of derivatives of 1 : 2-naphthophenazine or 1 : 2 : 1<1> : 2<1> or 1: 2.: 2<1> -1<1>-dinaphthazine which have a sulphogroup in the 8 position and also contain other hydroxyl- or sulpho-groups. Cotton and wool dyestuffs of very varied tints are obtained, some of which may be used in the manufacture of lakes and pigments. The oxyazine components have a marked affinity for cotton and may be developed on the fibre with diazo-compounds. In an example. the product obtained by alkaline fusion of 4 : 8-disulpho (or 4-oxy-8-sulpho)-1 : 2-naphthophenazine, which may be obtained from 4 : 8-disulpho (or 4-oxy-8-sulpho)-1 : 2-naphthoquinone and 1. : 2-diaminobenzene, is coupled with diazotized sulphanilic acid or naphthionic acid; the products dye wool yellow and red with a yellowish sheen. The corresponding dyestuff from 4-aminoazobenzene-4<1>-sulphonic acid dyes animal and vegetable fibres red, and in general the dyestuffs obtained by coupling diazotized amino-mono- or polyazo-dyestuffs with the aforesaid oxyazine dye cotton in red-brown to blackish-brown shades. In another example the same oxyazine is coupled with diazotized 4-amino-1-methylbenzene-3-sulphonic acid; the product forms insoluble brown lakes with metal salts, the barium, calcium, and copper-lakes being mentioned. In a further example, the same oxyazine is coupled with diazotized d 2-amino-4-ohlor-1-oxybenzene-5-sulphonic acid; the product dyes wool orange brown, which becomes violet-brown on chroming, or the dyeing may be done with a chromium mordant. A similar dyestuff is obtained from 6-nitro-2-amino-1- phenol-4-sulphonic acid. In another example, cotton is padded with a solution of the aforesaid oxyazine and developed with diazotized p-nitraniline, which gives a yellow shade, or dianisidine, which gives a violet-brown. In further examples, the compound obtained from 4-oxy-8-sulpho- 1 2 : :1<1> : 2<1> (or 1 : 2 : 2<1> : 1<1>)-dinaphthazine (obtained by condensing 4-oxy-8-sulpho-1 : 2-naphthoquinone with 1 :2-diaminobenzene) by alkaline fusion is used as a component. The products obtained by coupling it with naphthionic and sulphanilic acids respectively dye wool fast red and orange shades, and the disazo dyes obtained by coupling it with diazotized 4-aminoazobenzene- 4<1>-sulphonic acid or with the diazotized dyestuff sulphanilic acid#sodium 1-naphthylamine-6- sulphonate dye unmordanted cotton salmon-red and red-brown. Mordant dyestuffs for cotton are obtained by coupling the same oxyazine with an #-oxydiazo compound, such as 4-chlor-2-diazo-1- phenol-5-sulphonic acid, and the dyestuffs obtained by coupling it with 2-diazonaphthalene-1- sulphonic acid yield insoluble barium and calcium salts which form bordeaux pigments suitable for oil paints and carpet printing. In another example, cotton is padded with the same oxyazine and developed with 2-chlor-1-diazobenzene (orange), 5-nitro-2-diazo-1-methoxybenzene (scarlet) or tetrazotized dianisidine (currant). In another example, cotton is padded with the oxyazine obtained by alkaline fusion of 3 : 8-disulpho-1 : 21-naphthophenazine (from 3 : 8-disulpho- 1 : 2-naphthoquinone and 1 : 2-diaminobenzene) and developed with 5-nitro-2-diazo-1-methoxybenzene, yielding a currant colour; the same oxyazine yields brown to violet-brown wool dyes with diazo-arylsulphonic acids. In a further example the oxyazine obtained by fusing with potassium hydroxide 6- : 8-disulpho-1. 2À 1<1> : 2<1> (or 1 : 2 . 2<1>: 1<1>)-dinaphthazine, which is obtainable from 1 : 2-naphthoquinone-8-sulplionic acid and 1 : 2- diaminonaphthalene-6-sulphonic acid, is described; it may be coupled with diazobenzene- or diazonaphthalene-sulphonic acids to yield orange or brown wool dyes, or cotton may be padded with it and developed with diazotized 5-nitro-2-amino- 1-methoxybenzene, yielding a fast bordeaux shade. The oxyazine obtained by alkaline fusion of 4- oxy-8-sulphonaphtho-3 or 4-aminophenazine. (obtainable by condensing 4-oxy-1: 2-naphthoquinone-8-sulphonic acid with 4-nitro-1: 2-diaminobenzene and subsequent reduction) is similarly employed. 1 :2-Naphthoquinone disulphonic acids.- 1 : 2- naphthoquinone-4 : 8-disulphonic acid is obtained from 1-naphthol-4 : 8-disulphonic acid by converting it into the nitroso compound, reducing, and oxidizing the product. The 3 : 8-disulphonic acid is similarly obtained from 1-naphthol-3 : 8-disulphonic acid by reducing its nitroso or azo compounds and oxidizing the products. 1 : : 2-Naphthoquinone-8-sulphonic acid is made by coupling 2 : 8-naphthol sulphonic acid with a diazo compound, e.g. diazotized dichloraniline, reducing, and oxidizing the product. 4-Oxy-S-sulpho-1:2-naphithoquinone is obtained from 1 : 2-naphthoquinone-4 : 8-disulphonic acid by treating it with aniline, whereby the sulphonic group in the 4-position is replaced by a phenylamino group, and treating the product with mineral acid to replace the phenylamino group by a hydroxyl group.