Bayer Aktiengesellschaft

Volker Huhne

Roderich Raue

Hans-Peter Kuhlthau

Dietmar Kalz

Hans-Lothar Dorsch

Reiner Ditzer

Carl Taube

Cationic hydrazone dyestuffs of the general formula ##STR1## in which R.sub.1 stands for hydrogen, C.sub.1 -C.sub.4 -alkyl, C.sub.1 - to C.sub.4 -alkoxy, nitro or halogen,

Process for preparing cationic hydrazone dyestuffs

A method of preparation of cationic dyestuffs having the formula ##STR1## wherein A, B, R, and R.sup.1 are defined in the specification carried out in the substantial absence of solvent and removing water formed in the reaction.

Preparation of cationic methine dyestuffs

Trisazo dyestuffs of the formula ##STR1## wherein A, B, n, C and D have the meaning given in the description. The new dyestuffs are outstandingly suitable for dyeing natural or synthetic fibre materials containing hydroxyl groups or containing nitrogen, for example cellulose fibres in all states of processing, especially cotton and regenerated cellulose, and also wool, wool/cellulose union, silk, nylon, leather and paper. Dyeings obtained show good fastness properties, especially good fastness to water and to perspiration following an after treatment with cationic auxiliaries.

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Leverkusen, Germany

Volker Huhne