Process for dry quaternization of azo compounds

摘要

Certain solid dye bases which are precursors of acrylic fiber dyes and which contain a tertiary nitrogen atom are effectively quaternized in high yield and purity in a "dry state" quaternization process comprising contacting the dye base with an essentially stoichiometric amount of an alkylating agent at a temperature of 30 DEG -90 DEG C., said alkylating agent being added to said dye base gradually at a rate such that the reaction mixture is a free-flowing solid throughout the reaction.