Method of producing a toner particle

Patent metadata

Field	Value
Publication number	US-9575424-B2
Application number	US-201514639412-A
Country	US
Kind code	B2
Filing date	Mar 5, 2015
Priority date	Mar 12, 2014
Publication date	Feb 21, 2017
Grant date	Feb 21, 2017

Abstract

A toner particle production method has an annealing step that is performed after the preparation of a resin solution by the dissolution or dispersion, in an organic solvent, of a binder resin having a polyester resin as its major component and a block polymer having a polyester segment and a vinyl polymer segment, and the preparation of a resin particle dispersion in which resin particles are dispersed by a dissolution suspension method, wherein, in this annealing step, the temperature of the obtained resin particle dispersion is held for at least 60 minutes in the temperature range from TgA-15 (° C.) to TmA (° C.), and under the conditions of a temperature variation range of not more than 20° C. and a temperature variation rate of not more than 0.35° C./minute.

First claim

What is claimed is:

1. A method of producing a toner particle, comprising the steps of:
preparing a resin solution by dissolving, in an organic solvent, a binder resin having a polyester resin as its major component, and a block polymer having a crystalline polyester segment and a vinyl polymer segment;
preparing a resin solution dispersion by dispersing the resin solution in an aqueous medium; and
removing the organic solvent present in the resin solution dispersion to produce a resin particle dispersion in which a pre-annealing-treatment resin particle is dispersed in the aqueous medium,
the method further comprising a step of holding the resin particle dispersion for at least 60 minutes under temperature conditions that satisfy the following (i), (ii), and (iii):
(i) from TgA-15 (° C.) to TmA (° C.);
(ii) a temperature variation range of not more than 20° C.; and
(iii) a temperature variation rate of not more than 0.35° C./minute,
where TgA (° C.) indicates a glass transition point of the pre-annealing-treatment resin particle and TmA (° C.) indicates an onset temperature of an endothermic peak originating from the block polymer present in the pre-annealing-treatment resin particle.

2. The method of producing a toner particle according to claim 1 , wherein the temperature range in the annealing step is from TgA-15 (° C.) to TcA (° C.), which is a temperature at the finish of the heat generation that accompanies crystallization of the block polymer present in the pre-annealing-treatment resin particle.

3. The method of producing a toner particle according to claim 1 , wherein the polyester segment of the block polymer has a unit expressed by formula (1) below and a unit expressed by formula (2) below and satisfies the relationship 14≦m+n≦22:

(m in formula (1) represents an integer from 6 to 14)

(n in formula (2) represents an integer from 6 to 16).

4. The method of producing a toner particle according to claim 1 , wherein a glass transition point TgB (° C.) of the vinyl polymer segment of the block polymer is equal to or greater than TmA (° C.).

5. The method of producing a toner particle according to claim 1 , wherein the mass ratio (C/A) between the polyester segment (C) and the vinyl polymer segment (A) in the block polymer is 40/60 to 70/30.

6. The method of producing a toner particle according to claim 1 , wherein the vinyl polymer segment comprises a segment originating from a styrene.

Assignees

• Canon Kk

Inventors

• Nakagawa Yoshihiro
• Tanaka Masatake
• Isono Naoya
• Shimano Tsutomu
• NOJI Shintaro
• Yoshida Yu

Classifications

• G03G9/08788

  Block polymers · CPC title

• G03G9/08795

  characterised by their chemical properties, e.g. acidity, molecular weight, sensitivity to reactants · CPC title

• G03G9/0821

  characterised by physical parameters (magnetic parameters G03G9/083) · CPC title

• G03G9/08724

  Polyvinylesters · CPC title

• G03G9/0804 Primary

  whereby the components are brought together in a liquid dispersing medium · CPC title