| abstract |
Provided is a developer that is excellent in low-temperature fixability, offset resistance, and blocking resistance of toner, and that can realize a high-quality image without carrier adhesion and toner scattering and without fogging. A developer includes a binder resin containing an amorphous resin and a crystalline resin, a single monomer containing 99 to 80% by weight of a radical polymerizable monomer and 1 to 20% by weight of a sulfonic acid monomer. A copolymer particle obtained by polymerizing a monomer, the copolymer particle having an average primary particle diameter of 0.01 to 2 μm, and an electric resistivity R (Ω · cm ) Is a common logarithm value (LogR) of 12 to 25, F1 represented by the following formula (1) is 63 to 75 sec / (50 · cm3), and F2 represented by the following formula (2) is 30 to 100 Oe. -The carrier which is g / cm3. (1) F1 = AD × FR, (2) F2 = AD × Hc, where AD: apparent density, FR: fluidity, Hc: coercive force [selection diagram] None |