Dainippon Ink Chemicals, Inc.

Norio Aoki

Masanobu Nakamura

Kinji Shinzo

Toshiro Kogawara

Hideki Gambayashi

Ryozo Sugawara

Yoshinori Shimane

An electrostatic image developer is provided which has superior fixation properties and anti-offset properties, exhibits stable charge behavior even during continuous printing, and has superior durability and permits a high-quality image to be obtained. This electrostatic image developer is a toner composition containing colored resin particles comprising at least a binder resin, a colorant, and a charge control agent, wherein (1) an epoxy compound with a valence of 5 or more, (2) a polybasic acid compound having a valence of 2 or more selected from the group consisting of polybasic acids and/or acid anhydrides and/or lower alkyl esters thereof, and (3) a polyvalent alcohol having a valence of 2 or more, are employed as chief structural components of the binder resin, and a polyester resin is produced by reacting components (1)-(3) simultaneously, or by first reacting components (1) and (3), and subsequently reacting component (2), or by first reacting components (1) and (2), and subsequently reacting component (3).

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Ohmiya, Japan

Norio Aoki