Hydrochloric Acid → Perylene

Participants

Reaction Steps

0.7 part of stearylamine are dissolved warm in 60 ml of isopropanol and to this solution are added 35 parts by volume of about 37% aqueous hydrochloric acid. With stirring, the alkaline perylenetetracarboxylic acid/stearic acid solution is added dropwise to this mixture in the course of 15 minutes at 60° C. The formation of the anhydride imide is brought to completion by stirring the acid suspension for 31/2 hours at reflux temperature. The red pigment suspension is then filtered at about 70° C. The filter cake is washed neutral with water and dried in a vacuum cabinet at 80° C., affording 29.8 parts of a perylene pigment which produces strong red colourations of excellent fastness properties when it is incorporated in alkylmelamine stoving lacquers.

Provenance & Evidence