Abstract: Purification of hydrophobic solids by forming granules in the presence of water comprises treating the solids, if desired more than once, with one or more different two-phase systems comprisingA) a phase which wets the solids and effects granule formation and which consists essentially of one or more water-immiscible or partially water-miscible organic liquids, andB) a phase which takes up the impurities and which consists essentially ofB1) water, one or more water-miscible organic liquids and if desired an inorganic acid or an inorganic base, orB2) water and an inorganic acidin the heat and subsequently separating the resulting granules from the aqueous phase.

Abstract: Salts of esterified rhodamine dyes are prepared in granular form by precipitating the rhodamine dyes with sodium chloride from an aqueous medium containing a water-miscible solvent by adding the sodium chloride at 80.degree.-100.degree. C., which precipitates the dyes in liquid form from the aqueous medium, then stirring the liquid dyes to convert them into a droplet form and then chilling the droplets by direct cooling to below 65.degree. C.

Abstract: Stable solutions of azo dyes obtained by diazotizing and coupling m-phenylenediamine or derivatives thereof are prepared after the reaction has ended by treating the resulting reaction mixture with from 0.1 to 1.2 moles of formic acid, based on 1 mole of m-phenylenediamine, at from 60.degree. C. to the boiling point of the reaction mixture.

Abstract: Liquid formulations of basic azo dyes are prepared from unsubstituted or C.sub.1 -C.sub.4 -alkyl- or C.sub.1 -C.sub.4 -alkoxy-substituted m-phenylenediamine by diazotizing and coupling in carboxylic acid solution, which comprises performing the reaction with 0.76 to 0.95 mole of nitrile, calculated as nitrous acid and based on 1 mole of m-phenylenediamine, and then heating the resulting reaction mixture at from 60.degree. C. to the boiling point of the reaction mixture.

Abstract: Completely esterified rhodamine dyes of the formula ##STR1## where R, R.sup.2 and R.sup.4 are independently of one another methyl or ethyl, R.sup.1 and R.sup.3 are independently of one another hydrogen, methyl or ethyl, R.sup.5 and R.sup.6 are independently of one another hydrogen or methyl and A.sup..crclbar. is an anion, are prepared from compounds of the formula II ##STR2## or from the corresponding water addition products by esterification with dialkyl sulfates in solvents by using .gamma.-butyrolactone, alkylene carbonates, dialkyl carbonates, methoxypropyl acetate or dialkyl phthalates as solvent and working in the presence of an excess of a base, based on dialkyl sulfate.

Abstract: Polyhalocopper phthalocyanine pigments of high color strength are prepared by recrystallizing the finely divided agglomerated crude pigment in a heterogeneous aqueous organic phase at elevated temperatures by a process in which the aqueous organic phase used is a heterogeneous mixture of an aliphatic ketone having a total of 3 to 9 carbon atoms and water. The process gives the pigments in the form of spherical granules which are dust-free or have a low dust content. The pigments give deep, brilliant colorations of pure hues.

Abstract: Solutions of nitrosylsulfuric acid in sulfuric acid are manufactured by reacting nitric acid with sulfur in sulfuric acid or oleum. Less than 0.33 gram atom of sulfur is employed per mole of nitric acid, and after completion of the reaction the free nitric acid still present in the nitrosylsulfuric acid solution is reduced with lactones.

Abstract: Auramine salts having an ester of sulfopropionic acid as anion. The salts are more stable in storage than known auramine salts and therefore very suitable for the preparation of storage-stable solutions.