Dainippon Ink and Chemicals, Incorporated

Other

Hiroyuki Terada

Kinji Shinzo

Yoshinori Shimane

Masanobu Nakamura

Satoshi Ogawa

Masahiko Kubo

Hideki Watanabe

Tadayuki Sawai

Ryozo Sugawara

Katsuyuki Ogura

Hiroyuki Mariko

The present invention provides a method for producing an aqueous dispersion of thermoplastic resin microparticles containing considerably less residual solvent remaining in resin particles, and a toner for electrophotography containing considerably less residual solvent. A self-water-dispersible thermoplastic resin is swollen using an organic solvent having a boiling point lower than 100&#xb0; C., which does not dissolve but can swell the self-water-dispersible thermoplastic resin, to produce a swollen material and the resulting swollen material is dispersed into an aqueous medium in the form of microparticles to produce an initial aqueous dispersion, and then the organic solvent is removed from the initial aqueous dispersion to prepare a dispersion. A toner for electrophotography contains microparticles obtained by separating microparticles of the self-water-dispersible thermoplastic resin from the aqueous dispersion of thermoplastic resin microparticles and drying the microparticles.

Method for producing aqueous dispersion of thermoplastic resin microparticles and toner for electrophotography

A toner for electrophotography comprises: a coloring agent and a binding resin comprising a polyester resin constituted of cyclohexanedimethanol as an essential polyol component, wherein the toner has, at 110&deg; C., a storage elastic modulus of 3&times;10 Pa or less and a loss elastic modulus of 6&times;10 Pa or less, and, at 150&deg; C., a storage elastic modulus of 1&times;10 Pa or more and a loss elastic modulus of 1&times;10 Pa or more.

Toner for electrophotography

Use of a polyester resin obtained by reacting a divalent or higher epoxy compound, a dibasic or higher polybasic acid compound selected from a polybasic acid and/or acid anhydride and/or lower alkyl ester thereof, and a divalent or higher polyvalent alcohol in a toner for electrostatic charge development containing at least a binder resin, a colorant, and a charge control agent can provide a toner for a non-magnetic single component development having excellent fixing properties, offset resistance and development durability.

Toner for non-magnetic single component development

Growing community of inventors

Funabashi, Japan

Hiroyuki Terada