Toner and process for producing toner

Patent metadata

Field	Value
Publication number	US-9921501-B2
Application number	US-201715457159-A
Country	US
Kind code	B2
Filing date	Mar 13, 2017
Priority date	Mar 18, 2016
Publication date	Mar 20, 2018
Grant date	Mar 20, 2018

Abstract

A toner having a toner particle which contains a binder resin, a fatty acid metal salt, and a resin having an ionic functional group, in which the fatty acid metal salt is a fatty acid metal salt of a polyvalent metal with valency of 2 or higher and a fatty acid with carbon atom number of at least 8 and not more than 28, and the acid dissociation constant pKa of the resin having an ionic functional group is at least 6.0 and not more than 9.0.

First claim

What is claimed is:

1. A toner comprising a toner particle which contains a binder resin, a fatty acid metal salt, and a resin having an ionic functional group, wherein
the fatty acid metal salt is a fatty acid metal salt of a polyvalent metal with valency of 2 or higher and a fatty acid with carbon atom number of 8 to 28, where the fatty acid metal salt is mixed in said toner particle with the binder resin and the resin having an ionic functional group, and
the acid dissociation constant pKa of the resin having an ionic functional group is 6.0 to 9.0.

2. The toner according to claim 1 , wherein
X is 0.10 to 5.00 when the content of the resin having the ionic functional group is X parts by mass, and
a ratio Y/X is 0.050 to 3.000 when the content of the fatty acid metal salt is Y parts by mass relative to 100 parts by mass of the binder resin.

3. The toner according to claim 1 , wherein weight average molecular weight (Mw) of the resin having the ionic functional group is 10,000 to 75,000.

4. The toner according to claim 1 , wherein the polyvalent metal with valency of 2 or higher included in the fatty acid metal salt is selected from the group consisting of Al, Ba, Ca, Mg, Zn, Fe, Ti, Co, and Zr.

5. The toner according to claim 1 , wherein hydrophobicity parameter HP of the resin having the ionic functional group is at least 0.55, where HP indicates the volume fraction ratio of heptane at precipitation point of the resin having the ionic functional group when heptane is added to a solution containing 0.01 parts by mass of the resin having the ionic functional group and 1.48 parts by mass of chloroform.

6. The toner according to claim 1 , wherein the resin having the ionic functional group contains a polymer having an ionic functional group represented by Formula (1):

where R 1 each independently represents a hydroxyl group, a carboxy group, an alkyl group with carbon atom number of 1 to 18, or an alkoxy group with carbon atom number of 1 to 18; R 2 represents a hydrogen atom, a hydroxyl group, an alkyl group with carbon atom number of 1 to 18, or an alkoxy group with carbon atom number of 1 to 18; g is an integer of 1 to 3; and his an integer of 0 to 3.

7. The toner according to claim 1 , wherein when 0.10 g of the resin having the ionic functional group is dissolved in 150 ml of tetrahydrofuran, pH of the tetrahydrofuran solution is less than 7.0.

8. A process for producing a toner comprising a toner particle which contains a binder resin, a pigment, a fatty acid metal salt, and a resin having an ionic functional group, wherein
the fatty acid metal salt is a fatty acid metal salt of a polyvalent metal with valency of 2 or higher and a fatty acid with carbon atom number of 8 to 28, where the fatty acid metal salt is mixed in said toner particle with the binder resin and the resin having an ionic functional group, and
the acid dissociation constant pKa of the resin having the ionic functional group is 6.0 to 9.0,
the process comprising step (i) or (ii);
(i) a step in which a polymerizable monomer composition containing a pigment, a fatty acid metal salt, and a resin having an ionic functional group, and a polymerizable monomer for constituting a binder resin is granulated in an aqueous medium and the polymerizable monomer contained in the granulated particle is polymerized to give a toner particle; and
(ii) a step in which a mixture solution containing a binder resin, a pigment, a fatty acid metal salt, and a resin having an ionic functional group, which is dissolved or dispersed in an organic solvent, is granulated in an aqueous medium and the organic solvent included in the granulated particle is removed to give a toner particle.

Assignees

• Canon Kk

Inventors

• Mochizuki Shinsuke
• Nakayama Kenichi
• Kawamura Masashi
• Tominaga Tsuneyoshi
• Nakamura Kunihiko
• Shimano Tsutomu
• Toyoda Takayuki
• Kuroki Shiro

Classifications

• G03G9/08755

  Polyesters · CPC title

• G03G9/08711 Primary

  with esters of acrylic or methacrylic acid · CPC title

• G03G9/0806 Primary

  whereby chemical synthesis of at least one of the toner components takes place · CPC title

• G03G9/0819

  characterised by the dimensions of the particles · CPC title

• G03G9/0918

  Phthalocyanine dyes · CPC title