Bayer Aktiengesellschaft

Dietmar Kalz

Karl-Heinz Reinhardt

Stephan Michaelis

Dieter Arlt

Roderich Raue

Gerhard Wolfrum

Bernd Klinksiek

Reinold Schmitz

Karl Reizlein

Ferdinand Kummeler

Hans-Lothar Dorsch

Manfred Zimmermann

Volker Huhne

Gunter Heinrich

Carsten Gerdes

Thomas Pelster

Josef Schroder

Helmut Blaser

The present invention relates to a process for preparing compounds of formula (I) ##STR1## wherein A completes an unsubstituted or substituted heteroaromatic ring and

Process for the preparation of quinophthalones

Compounds of the general formula (I) or tautomeric forms thereof ##STR1## wherein Ar.sub.1 and Ar.sub.2 independently of one another denote radicals to complete optionally substituted carbocyclic aromatic rings, B denotes an optionally substituted alkylene group or a radical of the formula ##STR2## wherein r represents a number from 1 to 4, the ends of which are in each case bonded to an aromatic C atom of the two radicals Ar.sub.1 and Ar.sub.2, and

Bridged perinones/quinophthalones

The present invention relates to compounds of the formula (I)

Bridged anthraquinones

Process for the preparation of compounds of the general formula (I) ##STR1## by reaction of aromatic dicarboxylic acids of the formula (II) ##STR2## or anhydrides and/or esters thereof with aromatic diamines of the formula (III) ##STR3## wherein A and B have the meaning given in the description, characterized in that the reaction of (II) with (III) is carried out in a reaction medium which comprises water and a hydrotropic compound which has a dielectric constant .epsilon. of 20 to 60 at 25.degree. C.

Process for the preparation of polycyclic compounds

A process for the preparation of N,N'-disubstituted 1,4-diaminoanthraquinones has been found which is characterized in that 1,4-dihydroxyanthraquinones are reacted with aliphatic or aromatic amines in the presence of a hydroxycarboxylic acid as a condensation auxiliary.

Process for the preparation of N,N'-disubstituted

The invention relates to a process in which a melt is mixed with, and emulsified in a colder aqueous phase at a temperature below the crystallization point of the molten compound, the melt only solidifying in the form of the dispersed particles after the emulsification step. To this end, the melt is sprayed into the aqueous phase to form a preliminary emulsion (12) and the preliminary emulsion is finely dispersed for 0.005 s to 0.15 s in a following homogenization nozzle (8) to form an emulsion (15) which then solidifies to form the final crystal suspension. The particle size can be clearly and reproducibly adjusted through the nozzle pressure during the emulsification step. The process may be used in particular for the production of highly concentrated dispersions of high-melting organic materials.

Production of dispersions of spherical particles by crystallization of

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

Acylamino quinophthalone compounds which are free from sulfonic acid groups and correspond to the formula ##STR1## in which R.sub.1 and R.sub.2 are hydrogen, halogen, acylamino or lower alkoxy with the proviso that one of the residues R.sub.1 and R.sub.2 denotes acylamino while the other residue stands for hydrogen, halogen or a lower alkoxy; R.sub.3 is hydrogen, halogen or a lower alkoxy; X is a substituent; and n is a number from 0 to 3; are disclosed. The compounds useful as dyestuffs for hydrophobic fiber materials, e.g. polyester, are prepared by reacting an acylamino phthalic acid, the anhydride thereof, or mixtures of acylamino phthalic acids or the anhydrides thereof with a 3-hydroxy-quinalide.

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Neunkirchen, Germany

Dietmar Kalz