Patent ID: 8431307

Claim:
An electrographic toner, comprising: a core layer including a binder, a colorant and two or more types of releasing agents; and a shell layer covering the core layer, wherein the binder contains a non-crystalline polyester resin and a crystalline polyester resin, the amount of the non-crystalline polyester resin being 70 weight (wt) % or more based on the total amount of the binder, the amount of the crystalline polyester resin being 30 wt % or less based on the total amount of the binder, and wherein the non-crystalline polyester resin, the crystalline polyester resin and a major releasing agent that accounts for 60% or more of the total amount of the two or more types of releasing agents satisfy the following: SP ( A )− SP ( B )≧3.0 (1) SP ( B )− SP ( W )≦2.0 (2) 10,000≦ Mw ( B )≦30,000 (3) 1.5%≦ Mw ( B , less than 1,000)≦5.0% (4), where SP(A), SP(B) and SP(W) respectively denote solubility parameters (in units of (J/cm 3 ) 1/2 ) of the non-crystalline polyester resin, the crystalline polyester resin and the major releasing agent, Mw (B) denotes a weight average molecular amount of a tetrahydrofuran (THF)-soluble component contained in the crystalline polyester resin measured by gel permeation chromatography (GPC), and where Mw (B, less than 1,000) denotes a molecular weight range of less than 1,000 g/mole of the THF-soluble component contained in the crystalline polyester resin measured by GPC.