Patent ID: 6177224
Filing Date: 2001-01-23
Classification: G03G

Abstract:
A method of manufacturing an electrophotographic toner, the method comprising the step of:mixing at least toner particles and an additive for a predetermined mixing time t to produce an electrophotographic toner,wherein:said predetermined mixing time t is set with chargeability and preservation of said electrophotographic toner, both of which change according to duration of a mixing time of the toner particles and the additive, the preservation being quantified by measuring penetration of a needle of a penetration test device when the needle is introduced perpendicularly into said electrophotographic toner; andlet t.sub.2 be a first mixing time, at which the chargeability reaches a second order singular point p.sub.2 showing a maximum value, and let t.sub.3 be a second mixing time, at which the preservation reaches a singular point p.sub.3, having a maximum value then said predetermined mixing time t is set within a range, t.sub.3.ltoreq.t.ltoreq.t.sub.2.