Bayer Aktiengesellschaft

Carsten Gerdes

Bernd Klinksiek

Klaus Walz

Karl-Rudolf Gassen

Hans Schulze

Karlheinrich Meisel

Dietmar Kalz

Karl Reizlein

Gerd-Friedrich Renner

Ferdinand Kummeler

Manfred Zimmermann

Gunter Heinrich

Reiner Ditzer

Lothar Klein

.beta.-Hydroxyalkylpicolinium salts of the formula (I) ##STR1## wherein A, R.sup.1 to R.sup.3 and X have the meanings given in the description, which are obtained by reaction of picolines of the formula (II) ##STR2## with alkylene oxides of the formula (III) in the presence of a 1- to 3-basic acid and in water or an organic solvent as the reaction medium and are used as intermediate products for the preparation of cationic dyestuffs, and dyestuff preparations comprising such cationic dyestuffs.

Process for the preparation of beta-hydroxyalkypicolinium salts

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

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Leverkusen, Germany

Carsten Gerdes