DRY-TYPE TONER INCORPORATING ELECTRIC CHARGE CONTROL AGENT OF AZO DYE MIXTURE

摘要

PURPOSE: To provide a dry toner contg. an electric charge controlling agent made of an azo dye mixture by incorporating resin particles, a coloring material and an electric charge controlling agent contg. 'Zapon Yellow 141(R)' made by BASF Corp. CONSTITUTION: This dry toner contains resin particles, a coloring material and an electric charge controlling agent contg. Zapon Yellow 141 consisting of about 95wt.% Solvent Yellow 81 and about 5wt.% Solvent Orange 56. The pref. amt. of the Zapon Yellow 141 is 0.25-0.75wt.% of the total amt. of this toner. The resin particles are preferably based on a styrene-acrylic copolymer. This dry toner is used in combination with an uncoated ferrite carrier. A large amt. of Zapon Yellow 141 increases the quantity of electric charges in a short period of time but its transfer to the carrier reduces the ability of the carrier to electrostatic charge the toner.