Zeon Corporation

Kojiro Akazaki

Takeru Chiba

Takashi Iga

Junichi Takashima

The present invention provides a method for producing a toner for electrostatic-image development comprising: a dispersing step of performing a dispersing treatment in which a cavitation effect is obtained on a color resin particle containing a binder resin, a colorant, a charge control agent, and a release agent in an aqueous dispersion medium so as to obtain a dispersion of the color resin particle; and a heating step of performing a heat treatment on the dispersion of the color resin particle at a temperature of equal to or more than a glass transition temperature of the color resin particle and 95° C. or less for a heating time of 5 minutes or more and 10 hours or less.

Method for manufacturing toner for electrostatic charge image development

Provided is toner which has good low-temperature fixability, shelf stability and hot offset resistance, and which suppresses a decrease in glossiness of an image. The toner comprising colored resin particles containing a binder resin, a colorant, a softening agent and a charge control agent, and an external additive, wherein a glass transition temperature (Tg) specified from a temperature dependence curve of a loss tangent (tan δ) obtained by dynamic viscoelastic measurement of the toner, is 50° C. or more and less than 90° C.; the loss tangent (tan δ) at the glass transition temperature (Tg) is 1.70 or less; in a temperature range of 90° C. or more and 160° C. or less, a lowest temperature (Ta) with a loss tangent of 1.50 is more than 95° C. and less than 145° C.; and a storage elastic modulus (G′) at the lowest temperature (Ta) is less than 56000 Pa.

Toner

A yellow toner which provides, even in small amounts, a sharper color and brighter gloss, and higher reflection density than ever before, and which has excellent light resistance. The yellow toner contains a binder resin and a yellow colorant, wherein, as the yellow colorant, at least one of the compound A represented by the following general formula (1) and the compound B represented by the following general formula (2), and the compound C represented by the following formula (3) are contained: 

Yellow toner

A toner which is less likely to cause toner leakage and which is less likely to cause aggregation after being left to stand under a high temperature condition. A toner for developing electrostatic images, comprising colored resin particles comprising a binder resin and a colorant, and an external additive, wherein a conditioned bulk density obtained by a powder flowability analyzing device is from 0.525 g/mL to 0.565 g/mL.

Growing community of inventors

Tokyo, Japan

Kojiro Akazaki