Ricoh Company, Ltd.

Tomotsugu Miyamoto

Yasuaki Iwamoto

Nobuyasu Makino

Kazuyuki Yazaki

Ryoichi Ito

Mitsuyoshi Izu

A two-step process for the production of a toner for developing electrostatic images, including a first pulverizing step wherein a toner composition containing a binder and a coloring agent is pulverized to obtain preliminarily pulverized particles having a weight average particle diameter of 20-100 &mgr;m and containing no more than 50% by weight of particles having roundness of 0.90 or less, and a second pulverizing step wherein the preliminarily pulverized particles are finely pulverized to obtain finely pulverized particles having a weight average particle diameter of 5-13 &mgr;m and containing no more than 30% by weight of particles having roundness of 0.90 or less and no more than 15%, based on the total number of particles of the finely pulverized particles, of particles having a particle diameter of 5 &mgr;m or less.

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Mishima, Japan

Tomotsugu Miyamoto