ELECTROSTATIC IMAGE DEVELOPING TONER
An object of the present invention is to properly control a fluidity and chargeability of a toner and to achieve both of white-spot prevention and good toner consumption. The invention relates to an electrostatic image developing toner comprising: toner base particles that contain at least a binding resin, a coloring agent and a wax; and an external additive, wherein the external additive contains silica particles (a), silica particles (b), and particles (c), which satisfy particular requirements.
1 . An electrostatic image developing toner comprising:
toner base particles that contain at least a binder resin, a coloring agent, and a wax; and an external additive, wherein the external additive satisfies the following (A) to (C):
(A) the external additive contains fused silica particles (a),
(B) the external additive contains silica particles (b) different from the silica particles (a) and specific surface area of the silica particles (b) is 50 m 2 /g or more and 140 m 2 /g or less, and
(C) the external additive contains particles (c) different from the silica particles (a) and the silica particles (b) and the particles (c) are charged to have a reverse polarity to that of the silica particles (b) and have specific surface area of 5 m 2 /g or more and 300 m 2 /g or less.
2 . The electrostatic image developing toner according to claim 1 , wherein the particles (c) are silica particles treated with an aminosilane coupling agent.
3 . A method of producing an electrostatic image developing toner, comprising adding an external additive to toner base particles,
wherein:
the electrostatic image developing toner comprises
toner base particles comprising at least a binder resin, a coloring agent, and a wax, and
the external additive; and
the external additive satisfies the following (A) to (C):
(A) the external additive contains silica particles (a) obtained by a fusion method,
(B) the external additive contains silica particles (b) different from the silica particles (a) and specific surface area of the silica particles (b) is 50 m 2 /g or more and 140 m 2 /g or less, and
(C) the external additive contains particles (c) different from the silica particles (a) and the silica particles (b) and the particles (c) are charged to have a reverse polarity to that of the silica particles (b) and have specific surface area of 5 m 2 /g or more and 300 m 2 /g or less.
4 . The method according to claim 3 , wherein the particles (c) are silica particles treated with an aminosilane coupling agent.