Toner

Patent metadata

Field	Value
Publication number	US-9229345-B2
Application number	US-201414465722-A
Country	US
Kind code	B2
Filing date	Aug 21, 2014
Priority date	Aug 26, 2013
Publication date	Jan 5, 2016
Grant date	Jan 5, 2016

Abstract

The present invention is a toner including toner particles prepared by forming particles of a polymerizable monomer composition including a polymerizable monomer, a pigment, a pigment dispersant and a crystalline polyester resin in an aqueous medium, and polymerizing the polymerizable monomer, wherein the polymerizable monomer is a polymerizable monomer for preparing a vinyl copolymer, the difference in an SP value between the pigment dispersant and the crystalline polyester resin is −1.5 to +0.8, the difference in an SP value between the pigment dispersant an the vinyl copolymer is −1.1 to +1.2, the pigment dispersant has a polymer component and an adsorbable component adsorbed to the pigment, the polymer component is a vinyl polymer, the polymer component of the pigment dispersant has a number average molecular weight of 3,000 to 20,000, and a rate of adsorption of the pigment dispersant to the pigment is 30% or more.

First claim

What is claimed is:

1. A toner comprising toner particles prepared by forming particles of a polymerizable monomer composition comprising a polymerizable monomer, a pigment, a pigment dispersant and a crystalline polyester resin in an aqueous medium, and polymerizing the polymerizable monomer contained in the particles,
wherein the polymerizable monomer is a polymerizable monomer for preparing a vinyl copolymer,
the pigment dispersant satisfies (i) to (v):
(i) a difference (A−B) between an SP value (A) of the pigment dispersant and an SP value (B) of the crystalline polyester resin is −1.5 or more and +0.8 or less,
(ii) a difference (A−C) between the SP value (A) of the pigment dispersant and an SP value (C) of the vinyl copolymer is −1.1 or more and +1.2 or less,
(iii) the pigment dispersant contains a polymer component and an adsorbable component adsorbed to the pigment, and the polymer component is a vinyl polymer,
(iv) the polymer component of the pigment dispersant has a number average molecular weight (Mn) of 3,000 or more and 20,000 or less, and
(v) a rate of adsorption of the pigment dispersant to the pigment is 30% or more.

2. The toner according to claim 1 , wherein the polymer component of the pigment dispersant has a unit represented by Formula (6):

where R 8 represents a hydrogen atom or an alkyl group; R 7 represents a phenyl group, a carboxy group, a carboxylic acid ester group or a carboxylic acid amide group.

3. The toner according to claim 1 , wherein the polymer component of the pigment dispersant has a unit represented by Formula (1):

where R 1 represents a hydrogen atom or an alkyl group; R 2 represents a hydrogen atom, an alkyl group, a phenyl group, an aralkyl group or an amide group.

4. The toner according to claim 1 , wherein the polymer component of the pigment dispersant has a unit represented by Formula (2):

where R 3 represents a hydrogen atom or an alkyl group.

5. The toner according to claim 1 , wherein the adsorbable component of the pigment dispersant has a partial structure represented by Formula (3):

where one of R 4 , R 5 and Ar is a structure that binds to the polymer component through a single bond or a linking group;
R 4 represents an alkyl group, a phenyl group, a monovalent group represented by —OR 8 (where R 8 represents a hydrogen atom, an alkyl group, a phenyl group or an aralkyl group), or a monovalent group represented by —NR 9 R 10 (where R 9 and R 10 each independently represent a hydrogen atom, an alkyl group, a phenyl group or an aralkyl group), or a structure that binds to the polymer component through a single bond or a linking group (in this case, the structure corresponding to an alkyl group, a phenyl group, a monovalent group represented by —OR 8 , or a monovalent group represented by —NR 9 R 10 from which one hydrogen atom is removed); when R 4 is a structure that binds to the polymer component, the linking group binding to R 4 is an amide group, an ester group, a urethane group, a urea group, an alkylene group, a phenylene group, a divalent group represented by —O—, a divalent group represented by —NR 6 — (where R 6 represents a hydrogen atom, an alkyl group, a phenyl group or an aralkyl group), or a divalent group represented by —NHCH(CH 2 OH)—;
R 5 represents an alkyl group, a phenyl group, a monovalent group represented by —OR 8 (where R 8 represents a hydrogen atom, an alkyl group, a phenyl group or an aralkyl group), or a monovalent group represented by —NR 9 R 10 (where R 9 and R 10 each independently represent a hydrogen atom, an alkyl group, a phenyl group or an aralkyl group), or a structure that binds to the polymer component through a single bond or a linking group (in this case, the structure corresponding to an alkyl group, a phenyl group, a monovalent group represented by —OR 8 , or a monovalent group represented by —NR 9 R 10 from which one hydrogen atom is removed); when R 5 is a structure that binds to the polymer component, the linking group binding to R 5 is an alkylene group, a phenylene group, a divalent group represented by —O—, a divalent group represented by —NR 6 — (where R 6 represents a hydrogen atom, an alkyl group, a phenyl group or an aralkyl group), a divalent group represented by —NHCOC(CH 3 ) 2 —, or a divalent group represented by —NHCH(CH 2 OH)—;
Ar represents an aryl group or a structure that binds to the polymer component through a single bond or a linking group (in this case, the structure corresponding to an aryl group from which one hydrogen atom is removed); when Ar is a structure that binds to the polymer component, the linking group binding to Ar is an amide group, an ester group, a urethane group, a urea group, an alkylene group, a phenylene group, a divalent group represented by —O—, a divalent group represented by —NR 6 — (where R 6 represents a hydrogen atom, an alkyl group, a phenyl group or an aralkyl group), or a divalent group represented by —NHCH(CH 2 OH)—.

6. The toner according to claim 1 , wherein the average number of the adsorbable components per molecule of the pigment dispersant is 1 or more and 6 or less.

7. The toner according to claim 1 , wherein the crystalline polyester resin is a polyester resin prepared by reacting
an aliphatic dicarboxylic acid represented by Formula (4):
HOOC—(CH 2 ) m —COOH  (4)

where m represents an integer of 4 or more and 16 or less; and
an aliphatic diol represented by Formula (5):
HO—(CH 2 ) n —OH  (5)

where n represents an integer of 4 or more and 16 or less.

8. The toner according to claim 1 , wherein the pigment dispersant has an acid value of 10 mgKOH/g or less.

9. The toner according to claim 1 , wherein the pigment dispersant has an amine value of 5 mgKOH/g or less.

10. The toner according to claim 1 , wherein the pigment has a π-conjugate plane.

11. The toner according to claim 1 , wherein the pigment is at least one selected form the group consisting of carbon black, Pigment yellow 155, Pigment Red 122 and Pigment Red 150.

Assignees

• Canon Kk

Inventors

• Ikeda Naotaka
• Hashimoto Yasuhiro
• Terui Yuhei
• Shibahara Shohei
• Seki Masanori
• Hasegawa Waka

Classifications

• G03G9/08791

  characterised by the presence of specified groups or side chains · CPC title

• G03G9/0904

  Carbon black · CPC title

• G03G9/08711

  with esters of acrylic or methacrylic acid · CPC title

• G03G9/08797

  characterised by their physical properties, e.g. viscosity, solubility, melting temperature, softening temperature, glass transition temperature · CPC title

• G03G9/08755 Primary

  Polyesters · CPC title