| 摘要 |
PURPOSE:To obtain a toner superior in powder fluidity, high in image quality and transferability, and stable in case of successive long copying by heat treating specified colored thermoplastic resin particles and specified resin microparticles at a specified temperature. CONSTITUTION:The colored thermoplastic resin particles having a flow temperature of t1 deg.C measured by the KOUKASHIKI Flow Tester and a particle diameter of 2-30mum and the resin microparticles having a flow temperature of t2 deg.C higher than t1 deg.C and a particle diameter of <=1mum are heat treated at temperatures of >t1 deg.C and <t2 deg.C to attach the resin microparticles to the surfaces of the colored thermoplastic resin particles, thus permitting a necessary quantity of electrostatic charge to be effectively obtained by increases of friction coefficient and surface areas due to the presence of the microparticles on the surfaces and by adding no or a little amount of a charge controller, and accordingly, images high in image quality and transferability to be obtained even during long successive copying operations. |
