Bayer Aktiengesellschaft

Horst Brandt

Karlheinz Wolf

Reinhold Hornle

Dieter Wiegner

Hans-Heinz Molls

Hans-Gunter Otten

Vaclav Kaspar

Manfred Hoppe

Karlheinz Hildenbrand

Klaus Leverenz

Udo Herrmann

Wolfgang Zarges

Hans Schulze

Gunter Gehrke

Jochen Koll

Dietrich Tegtmeyer

Fritz Bremer

Willy Schiwy

Heinz Dietrich Jordan

Rolf Muders

Erhard Schuffenhauer

Wolfgang Haebler

Hans-Werner Petroll

Klaus-Peter Sagner

Gottfried Popp

Ralf Friedricsen

Richard Buchele

Heinz Geiger

Friedrich Grimmelijkhuizen

Thomas Nagel

Manfred Baecker

To prevent dusting of a solid such as a crop protection agent, a pharmaceutical or a dyestuff, there is added thereto as a dustproofing agent a compound of the formula I ##STR1## in which Z represents Z.sub.1 or Z.sub.2 where

Dustproofing agents

The novel process for working up solutions or suspensions of organic synthesis products having a pH value of &lt;3, preferably &lt;1, is carried out with the aid of an asymmetrical, semipermeable membrane composed of cyclic polyureas with repeating structural units of the formula (I) ##STR1## wherein the substituents R.sup.1, R.sup.2, R.sup.3, R.sup.4, R.sup.5, X and Y and the index n are each as defined in the description.

Process for purifying organic synthesis products

To prepare storage-stable, low-dusting dyestuff granules which are readily soluble in plastics, a suspension of the dyestuff containing 0.1-5% by weight of a polyglycol are dried while being granulated.

Process for the preparation of improved dyestuff granules from

Mixtures of dyestuffs of the formulae I to IV ##STR1## wherein the radicals have the meanings customary in dyestuff chemistry, are excellent substitute products for the expensive anthraquinone dyestuff Disperse Blue 56.

Mixtures of blue azo disperse dyestuffs

Low-dust, storage-stable granules are obtained in a continuous operating process in which the powder to be granulated is granulated in succession in a high-speed and low-speed mixing granulator, with the addition of a granulating liquid, and is then dried in a fluidized bed into which a liquid containing a binder is sprayed. The process is particularly suitable for the preparation of dyestuff granules which can easily be dispersed in the use medium.

Process for the preparation of granules

Navy polyester dyeings which are produced by means of dyestuff mixtures based on azo dyestuffs from 2,4-dinitro-6-cyanoaniline and 3-acylamino-dialkylaminoanilines are distinguished by a very good wash fastness on using peroxide-containing domestic washing agents. Preferably the dyestuff formulations used contain a weakly acidic buffer system.

Process for preparing navy dyeings on polyester fibers using mixture of

The azo dyestuff of the formula ##STR1## having the interplanar spacings D/.ANG. 3.13, 3.36, 4.85, 9.26 and 13.94 for the five strongest lines having the relative intensity use 98, 89, 82, 100 and 87 is distinguished, compared to known modifications by an increased dye bath stability.

Stable gamma-modification of a benzisothiazole azo dyestuff

Mixtures of disperse dyestuffs

Mixed crystals of dyestuffs of the formula I ##STR1## wherein R denotes alkyl and

Dyestuff mixtures, a process for their preparation and a process for

Highly concentrated liquid preparations of disperse dyestuffs are obtained with a low consumption of energy by first adding a dispersing agent to the water-moist dyestuff press-cake to convert it into a form in which it is capable of flow, subjecting this product to wet grinding and increasing the dyestuff content of the resulting, insufficiently concentrated dispersion in a second step by means of a membrane separation process, for example pressure permeation.

Process for producing liquid dyestuff preparations

Organic pigments which provide an opaque color impression in binders and exhibit adequate flow properties in binders are obtained from pigments which provide a transparent color impression in binders in a simple way in that an azeotrope-forming agent which is appropriate for the liquid adhering to the pigment is added to the moist pigment obtained after the preparation, and the azeotropic mixture and any excess solvent which may be present are then distilled off.

Process for the preparation of opaque organic pigments

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Odenthal, Germany

Horst Brandt