Magenta toner for developing electrostatic images

A magenta toner for developing electrostatic images, comprising

• colored resin particles containing a binder resin and a magenta colorant, and an external additive,
• wherein a volume average particle diameter of the colored resin particles is from 5.5 μm to 7.0 μm;
• wherein the external additive contains silica particles;
• wherein the silica particles contain at least silica particles A having a number average particle diameter of from 5 nm to 30 nm and silica particles B having a number average particle diameter of from 31 nm to 100 nm;
• wherein a total content of the silica particles is from 0.5 part by mass to 4.5 parts by mass, with respect to 100 parts by mass of the colored resin particles;
• and
• wherein a liberation rate of the silica particles calculated by the following liberation rate measuring method is in a range of from 2.2% to 9.5%:
• [liberation rate measuring method]
• using an airflow classifier, a toner to be measured is classified to separate liberated silica particles from the toner;
• using a X-ray fluorescence spectrometer, a fluorescent X-ray intensity of a Si element in the toner before the classification and that of the Si element in the toner after the classification, are measured;
• and using measured values thus obtained, a liberation rate of the silica particles in the toner is calculated by the following formula (1):
• The liberation rate of the silica particles=[(the fluorescent X-ray intensity of the Si element in the toner before the classification−the fluorescent X-ray intensity of the Si element in the toner after the classification)/the fluorescent X-ray intensity of the Si element in the toner before the classification]×100 Formula (1)