Canon Kabushiki Kaisha

Yayoi Tazawa

Yasukazu Ayaki

Hitoshi Itabashi

Yoshinobu Baba

Yuzo Tokunaga

Takeshi Ikeda

Takaaki Kaya

Ryoichi Fujita

Shigeto Tamura

Yuichi Yajima

In a black toner having at least a binder resin and an iron-titanium composite oxide as a colorant; the iron-titanium composite oxide is contained in a specific amount; the black toner has a specific weight average particle diameter and a specific saturation magnetization; the black toner has, in X-ray diffraction thereof, a maximum peak at 2&#x3b8;=from 32.5 to 33.1 degrees, having a half width of 0.25 degree or less. The black toner has, in a proportion of less than 30% by number, an iron-titanium composite oxide having, in a sectional photograph of the toner, a maximum frequency of linearity within the range where the linearity is smaller than 2.4 and having a linearity of 3.0 or more, in regard to the number frequency distribution of the linearity of the iron-titanium composite oxide.

Black toner

A coloring agent for use in toners which comprises coloring particles modified with a surface modifier having in one molecule a hydrophilic moiety, a hydrophobic moiety, and a reactive moiety between the hydrophilic moiety and the hydrophobic moiety. Also disclosed is a toner comprising toner particles containing at least a binder resin and a coloring agent comprising the above surface-modified coloring particles.

Coloring agent for toner, and toner

A toner production process comprising the step of polymerizing a polymerizable monomer in the presence of (i) base particles containing at least a binder resin and (ii) a polymerization initiator. The polymerization initiator has in one molecule a hydrophilic moiety and a hydrophobic moiety and a reactive moiety between them, and the base particles are enlarged and/or surface-modified upon polymerization of the polymerizable monomer. Also disclosed is a toner having a circularity of from 0.92 to 1.0, which is produced by this process.

Process for producing toner

A toner is comprised of toner particles composed of at least a binder resin and a clorant, wherein the toner particles each have a coating layer formed on their surfaces in a state of particulate matters being stuck to one another. The particulate matters contains at least a silicon compound.

Toner, and process for producing toner

A process for producing toner particles is conducted by:

Growing community of inventors

Mishima, Japan

Yayoi Tazawa