Prepn. of granular dust-free pigments, free from solvent residue - using aminated cpd. such as aniline, (di)alkyl-aniline, alkylamine, or cycloalkyl-amine, for use in paints, plastics, inks, etc.

摘要

A method of preparing granular dust-free pigments or colorants which are easily dispersed involves agitation of an aq. dispersion of a pigment with an aminated cpd. The latter is liq. below 100 degrees C, and insol. in water at pH less than 7, but soluble at pH above 7, which it is at the start of the operation. The temp. is maintained above the m.pt. of the aminated cpd., and the pH lowered to below 7. The granules formed are recovered. The aminated cpd. is pref. aniline, a 1-8C mono- or di-alkyl aniline, a linear or branched alkylamine, or a 6-12 cycloalkylamine. The products can be used to pigment all materials such as surface coating media e.g. paints and inks, or plastic materials, the vehicle being chosen to be compatible with the material to be pigmented. The prod. can be obtd. without use of solvent, hence no distn. process is required.