Patent ID: 6013405
Filing Date: 2000-01-11
Classification: G03G

Abstract:
A developing agent comprising toner particles and carrier particles, said toner particles being obtained by pulverizing a kneaded mass of a toner material, including less than 21% of particles having a roundness of less than 0.93, and containing a binder resin, a coloring agent, and a charge controlling agent free from heavy metals,wherein the product between the toner particle diameter (.mu.m) and the carrier particle diameter (.mu.m) falls within a range defined in the following formula:252.ltoreq.A.multidot.B.ltoreq.522where A is a 50% average diameter of the toner particles, and B is a 50% average diameter of the carrier particles, andsaid toner particles have a 50% average particle diameter of 7.0 to 9.0 .mu.m, and said carrier particles have a 50% average particle diameter of 35 to 90 .mu.m.