Bayer Aktiengesellschaft

Bayer Aktiengesselschaft

Willi Schossler

Horst Behre

Heinz U Blank

Rolf Putter

Gunther Boehmke

Wolf-Dieter Schroer

Hans Schulze

Karlhans Jakobs

Otto Lindner

Frank Bartkowiak

The carrier mixture contains N-alkylphthalimides and compounds of the general formula ##STR1## in which R is C.sub.1 -C.sub.7 -alkyl; phenyl, benzyl or phenylethyl, which can be substituted by C.sub.1 -C.sub.4 -alkyl, C.sub.1 -C.sub.4 -alkoxy or C.sub.1 -C.sub.4 -alkoxycarbonyl,

Carrier mixture for the dyeing of polyester materials:

N-Alkyl-benzenesulphonamides, the alkyl group of which is open-chain C.sub.1 -C.sub.12 -alkyl or C.sub.5 -C.sub.7 -cycloalkyl and the benzene nucleus of which can be substituted by C.sub.1 -C.sub.4 -alkyl, can be heat-stablized by 10-1,000 ppm of one or more 2-mercapto-benzimidazole compounds of the formula ##STR1## wherein R.sup.1 denotes hydrogen of a C.sub.1 -C.sub.4 -alkyl group and

N-alkyl-benzenesulphonamide compositions

The invention relates to a process for the preparation of 1-amino-8-naphthol-4,6-disulphonic acid (K-acid) as the mono-alkali metal salt by reacting a mixture of naphthylaminetrisulphonic acids and/or salts thereof with an alkali metal salt solution and separating the K-acid as the mono-alkali metal salt, by acidification and crystallization. The product is a known valuable dyestuff intermediate.

Process for the preparation of 1-amino-8-naphthol-4,6-disulphonic acid

Process for the preparation of a nitroaminobenzene by nitrating an aminobenzene which is protected at the nitrogen wherein the nitration is carried out by the simultaneous combination of nitric acid and the aminobenzene to be nitrated, in the presence of inert solvents such as methylene chloride.

Process for the preparation of nitroaminobenzenes

The invention relates to a process for isolating H acid and K acid in the form of their monoalkali metal salts from acid aqueous solutions which contain these two acids and alkali metal ions and may contain other aminonaphtholdisulphonic acids, in which process H acid monoalkali metal salts are precipitated at elevated temperatures from solutions which contain not only sodium ions but also potassium ions and then precipitating K acid monoalkali metal salts by cooling down the filtrate obtained after separating off the H acid monoalkali metal salts.

Process for isolating H acid and K acid

A process has been invented for the preparation of a mono-alkali metal salt of 1-amino-8-naphthol-3,6-disulphonic acid comprising reacting 1-naphthylamine-3,6,8-trisulphonic acid and/or a salt thereof and/or a naphthylamine-trisulphonic acid isomer mixture and/or salt thereof with an alkali metal hydroxide solution at elevated pressure and elevated temperature and in the presence of an alcohol or alcoholate, and separating out the mono-alkali metal salt by acidification. The process results in the procurement of higher yields of the desired product and in the formation of less by-products.

Process for the preparation of 1-amino-8-naphthol-3,6-disulphonic acid

A process has been invented for the preparation of a mono-alkali metal of 1-amino-8-naphthol-3,6-disulphonic acid, comprising reacting 1-naphthylamine-3,6,8-trisulphonic acid and/or a salt thereof and/or a naphthylamine trisulphonic acid isomer mixture and/or salt thereof with an alkali metal hydroxide solution in the presence of an alcohol and/or alcoholate and in the presence of a substance which contains at least one oxygen atom bonded to a nitrogen atom, at elevated pressure and elevated temperature, and separating out the mono-alkali metal salt of 1-amino-8-naphthol-3,6-disulphonic acid by acidification. The process results in the procurement of higher yields of the desired product and in the formation of less by-products.

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Cologne, Germany

Willi Schossler