摘要:
Azo disperse dyestuffs are prepared by diazotization and coupling in an aqueous phase, the coupling being carried out in the presence of an ester of a lower aliphatic carboxylic acid.
摘要:
The process for the preparation of a 3-(4-hydroxyanilino)carbazole of the formula ##STR1## wherein R is hydrogen, alkyl having 1 to 8 carbon atoms or halogenoalkyl having 1 to 8 carbon atoms, comprising reacting a 3-aminocarbazole of the formula ##STR2## with p-hydroquinone or p-aminophenol or a mixture of p-hydroquinone and p-aminophenol in at least stoichiometric amounts by heating to a temperature of 150.degree. to 300.degree. C. with exclusion of oxygen.
摘要:
Carbazoleazomethines are prepared and sulfur dyestuffs are prepared by sulphurizing a carbazoleazomethine of the formula ##STR1## wherein R.sup.1 is hydrogen, hydroxyl, halogen, nitro, alkyl having 1 to 8 carbon atoms, alkoxy having 1 to 8 carbon atoms, dialkylamino having 1 to 4 carbon atoms per alkyl, alkanoyloxy having 1 to 8 carbon atoms, benzoyloxy, alkanoylamino having 1 to 8 carbon atoms or benzoylamino;R.sup.2 is hydrogen, hydroxyl, halogen, alkyl having 1 to 8 carbon atoms or alkoxy having 1 to 8 carbon atoms;R.sup.3 is hydrogen or alkyl having 1 to 7 carbon atoms;R.sup.4 is hydrogen or halogen; andR.sup.5 is hydrogen or alkyl having 1 to 8 carbon atoms.
摘要:
In the processs for isolating solid sulphur dyestuffs from crude sulphur dyestuff melts, the improvement comprises adding 10.sup.-4 to 1% by weight, relative to the amount of dyestuff, of an organic flocculating auxiliary to the crude dyestuff melt to produce a filterable dyestuff precipitate and then separating said precipitate.