Bayer Aktiengesellschaft

Erich Istel

Franz Zimmermann

Hans-Josef Buysch

Karlheinz Wolf

Reinhold Hornle

Konrad Nonn

Hans-Georg Gelhaar

Joachim Laser

Polyamides are stabilized by phenothiazines.

Stabilized polyamides

Stabilized shaped articles of polyamides are prepared in a simple manner, using a copper-I halide and a molar excess of an alkali or alkaline earth metal halide, by mixing copper(I)-halide and alkali or alkaline earth metal halide with caprolactum, polymerizing the mixture, granulating the melt of the stabilizer concentrate and processing the granules together with the granulated polyamide which is to be stabilized, to give shaped articles.

Process for the preparation of stabilized polyamides

Process for the preparation of water-soluble dyestuffs with a low salt content, characterized in that the water-soluble dyestuffs are salted out from their aqueous solutions and/or dispersions by adding salts which are volatile at temperatures of about 40.degree. C. to about 250.degree. C. under a pressure of about 10 mm Hg to about 760 mm Hg, the dyestuffs are isolated and the volatile salts are volatilized during the drying process.

Process for the preparation of water-soluble dyestuffs with a low salt

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Dormagen, Germany

Erich Istel