Patent ID: 8765346

Claim:
A magnetic single-component developer comprising: a spherical toner containing at least a magnetic powder and not containing a release agent in a binder resin; a nonspherical toner containing at least a magnetic powder and a release agent in a binder resin; and wherein according to measurements taken from a scanning electron microscope image taken from 100 toner particles in the magnetic single-component developer at a magnification of 3000×, circularity of the spherical toner, circularity of the nonspherical toner, and a particle number ratio (A)/(B) of the number (A) of particles of the spherical toner to the number (B) of particles of the nonspherical toner satisfy the expressions (1) to (3) below, Circularity of spherical toner ≧0.980 (1) Circularity of nonspherical toner ≦0.960 (2) 3/7≦particle number ratio ( A )/( B )≦5/5 (3).