Toner and method for producing toner

Patent metadata

Field	Value
Publication number	US-9785071-B2
Application number	US-201615234497-A
Country	US
Kind code	B2
Filing date	Aug 11, 2016
Priority date	Aug 21, 2015
Publication date	Oct 10, 2017
Grant date	Oct 10, 2017

Abstract

The toner comprising a toner particle having a core-shell structure that contains a core containing an amorphous resin A and a crystalline resin and a shell containing an amorphous resin B, wherein the amorphous resin A contains a styrene-acrylic resin, the content of the styrene-acrylic resin is at least 50% by mass based on the total mass of the amorphous resin A, a degree of compatibility A between the amorphous resin A and the crystalline resin is at least 50% and not more than 100%, and a degree of compatibility B between the amorphous resin B and the crystalline resin is at least 0% and not more than 40%.

First claim

What is claimed is:

1. A toner comprising a toner particle having a core-shell structure that contains a core and a shell on the core, wherein
the core comprises an amorphous resin A and a crystalline resin,
the shell comprises an amorphous resin B,
the amorphous resin A comprises a styrene-acrylic resin,
a content of the styrene-acrylic resin is at least 50% by mass based on the total mass of the amorphous resin A,
a degree of compatibility A between the amorphous resin A and the crystalline resin, calculated with the following formula (X), is at least 50% and not more than 100%
degree of compatibility A (%)=100−(100×Δ H ( A ))/(Δ H ( C )× C/ 100)  (X), and

a degree of compatibility B between the amorphous resin B and the crystalline resin, calculated with the following formula (Y), is at least 0% and not more than 40%
degree of compatibility B (%)=100−(100×Δ H ( B ))/(Δ H ( C )× D/ 100)  (Y),

wherein, in formulae (X) and (Y),
ΔH(A) represents an exothermic quantity (J/g) of an exothermic peak of a resin mixture A in differential scanning calorimetric analysis, the resin mixture A consisting of the amorphous resin A and the crystalline resin,
ΔH(C) represents an exothermic quantity (J/g) of an exothermic peak of the crystalline resin in differential scanning calorimetric analysis,
C represents a mass ratio (%) of the crystalline resin in the resin mixture A,
ΔH(B) represents an exothermic quantity (J/g) of an exothermic peak of a resin mixture B in differential scanning calorimetric analysis, the resin mixture B consisting of the amorphous resin B and the crystalline resin, and
D represents a mass ratio (%) of the crystalline resin in the resin mixture B.

2. The toner according to claim 1 , wherein the crystalline resin is a block polymer in which a crystalline polyester segment is bonded to an amorphous vinyl polymer segment.

3. The toner according to claim 2 , wherein a mass ratio of the crystalline polyester segment to the amorphous vinyl polymer segment is at least 30/70 and not more than 70/30.

4. The toner according to claim 1 , wherein the crystalline resin has a unit represented by the following formula (1) and a unit represented by the following formula (2), and

wherein, in formula (1), n represents an integer that is at least 6 and not more than 16, and

in formula (2), m represents an integer that is at least 6 and not more than 14.

5. The toner according to claim 1 , wherein the amorphous resin B contains at least 0.1 mol % and not more than 30.0 mol %, with respect to the total monomer-derived units, of an isosorbide unit given by the following formula (3)

6. A method for producing a toner comprising a toner particle having a core-shell structure that contains a core and a shell on the core, wherein
the core comprises an amorphous resin A and a crystalline resin,
the shell comprises an amorphous resin B,
the amorphous resin A comprises a styrene-acrylic resin,
a content of the styrene-acrylic resin is at least 50% by mass based on the total mass of the amorphous resin A,
a degree of compatibility A between the amorphous resin A and the crystalline resin, calculated with the following formula (X), is at least 50% and not more than 100%
degree of compatibility A (%)=100−(100×Δ H ( A ))/(Δ H ( C )× C/ 100)  (X), and

a degree of compatibility B between the amorphous resin B and the crystalline resin, calculated with the following formula (Y), is at least 0% and not more than 40%
degree of compatibility B (%)=100−(100×Δ H ( B ))/(Δ H ( C )× D/ 100)  (Y),

(wherein, in formulae (X) and (Y),
ΔH(A) represents an exothermic quantity (J/g) of an exothermic peak of a resin mixture A of the amorphous resin A and the crystalline resin in differential scanning calorimetric analysis,
ΔH(C) represents an exothermic quantity (J/g) of an exothermic peak of the crystalline resin in differential scanning calorimetric analysis,
C represents a mass ratio (%) of the crystalline resin in the resin mixture A,
ΔH(B) represents an exothermic quantity (J/g) of an exothermic peak of a resin mixture B of the amorphous resin B and the crystalline resin in differential scanning calorimetric analysis, and
D represents a mass ratio (%) of the crystalline resin in the resin mixture B), and wherein
the method comprises steps of:
forming, in an aqueous medium, a particle of a monomer composition that comprises the crystalline resin, the amorphous resin B, and a monomer capable of forming the amorphous resin A; and
obtaining a toner particle by polymerizing the monomer present in the particle of the monomer composition.

Assignees

• Canon Kk

Inventors

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

Classifications

• G03G9/09364

  obtained by reactions only involving carbon-to-carbon unsaturated bonds · CPC title

• G03G9/081 Primary

  by mixing the toner components in a liquefied state; melt kneading; reactive mixing · CPC title

• G03G9/09371

  obtained otherwise than by reactions only involving carbon-to-carbon unsaturated bonds · CPC title

• G03G9/08711 Primary

  with esters of acrylic or methacrylic acid · CPC title

• G03G9/09392 Primary

  Preparation thereof · CPC title