| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide an electrophotographic toner having excellent color reproducibility, in which the toner is obtained by granulation in an aqueous medium using at least a polyester resin as a resin component. <P>SOLUTION: A toner is prepared by granulating an oil phase, which comprises at least a matrix resin, a coloring agent, and a resin for a master batch for dispersing the coloring agent, and a releasing agent, in an aqueous medium. In the toner that satisfies an expression: 0≤¾SPa-SPb¾≤1.0 when a solubility parameter (SP value) of the resin for a master batch is to be Spa and an SP value of the matrix resin is to be SPb, the coloring agent is surface-treated by a surface treating agent, and when an SP value of the surface treating agent is to be SPc, an expression: 0≤¾SPa-SPc¾≤1.0 is satisfied, and when an SP value of the releasing agent is to be SPd, an expression: 1.0<SPd-SPa<5.0 is satisfied. The melting point of the releasing agent is 60°C to 85°C, and kinematic viscosity at 100°C is 10 mm<SP POS="POST">2</SP>/s or lower. <P>COPYRIGHT: (C)2012,JPO&INPIT |
