NIGROSINE COMPOUND, PRODUCTION OF HALOGENATED NIGROSINE COMPOUND, PRODUCTION OF NIGROSINE COMPOUND AND ELECTROSTATIC IMAGE DEVELOPING TONER CONTAINING SAME

摘要

PURPOSE:To obtain a nigrosine compound improved in dispersibility in a toner resin, compatibility with this resin and heat resistance and being useful as a positive charge-donating charge controller having high frictional charging characteristics by reacting a specified halogenated nigrosine compound with an amine compound. CONSTITUTION:A nigrosine dye (i) (e.g., C.I. Solvent Black 7) ls halogenated with a halogenating agent (ii) (e.g., Br) in a water-soluble organic solvent (iii) (e.g., dimethyl sulfoxide), component (iii) is removed from the product, and the product is treated with an alkali (iv) (e.g., NaOH) to obtain a halogenated nigrosine compound (a) of formula I (wherein D is a residue of component (i); X is a halogen atom) and a is 2-9). Component (a) is reacted with at least one active hydrogen-containing amine compound (b) selected from among an aliphatic amine, a hydroxyalkylamine and an alkoxyalkylamine to obtain a nigrosine compound of formula II (wherein Y is a residue of component (b), n and m are each 1-8, and n+m=2-9).