US 11,746,247 B2
Aqueous pigment dispersion liquid
Yosuke Sakai, Tokyo (JP); Misaki Narita, Tokyo (JP); Yasuhiro Yoshida, Tokyo (JP); Shinichiro Aoyagi, Tokyo (JP); Yoshikazu Murakami, Tokyo (JP); and Hiroyuki Shimanaka, Tokyo (JP)
Assigned to DAINICHISEIKA COLOR & CHEMICALS MFG. CO., LTD., Tokyo (JP)
Appl. No. 17/438,812
Filed by DAINICHISEIKA COLOR & CHEMICALS MFG. CO., LTD., Tokyo (JP)
PCT Filed Mar. 17, 2020, PCT No. PCT/JP2020/011658
§ 371(c)(1), (2) Date Sep. 13, 2021,
PCT Pub. No. WO2020/196082, PCT Pub. Date Oct. 1, 2020.
Claims priority of application No. 2019-055173 (JP), filed on Mar. 22, 2019; and application No. 2019-109366 (JP), filed on Jun. 12, 2019.
Prior Publication US 2022/0127485 A1, Apr. 28, 2022
Int. Cl. C09D 17/00 (2006.01); C08F 220/18 (2006.01); C08F 220/14 (2006.01); C08F 220/34 (2006.01); C08F 226/06 (2006.01); C08K 5/00 (2006.01); C09B 67/46 (2006.01); C08G 65/08 (2006.01); C08G 65/333 (2006.01); G03G 9/08 (2006.01)
CPC C09D 17/001 (2013.01) [C08F 220/14 (2013.01); C08F 220/1804 (2020.02); C08F 220/1807 (2020.02); C08F 220/34 (2013.01); C08F 226/06 (2013.01); C08G 65/08 (2013.01); C08G 65/33303 (2013.01); C08K 5/0041 (2013.01); C09B 67/009 (2013.01); C09D 17/003 (2013.01); G03G 9/0806 (2013.01); C08K 2201/003 (2013.01)] 6 Claims
 
1. An aqueous pigment dispersion liquid comprising:
a pigment;
a dispersant that disperses the pigment; and
an aqueous medium comprising water,
wherein the dispersant is a polymer comprising: a constitutional unit (A) derived from a monomer (A′); and a constitutional unit (B) derived from a monomer (B′) having a carboxy group or an amino group, wherein in the monomer (A′), a group comprising a (meth)acryloyloxy group or a (meth)acryloylamino group is bonded to one end of any one of the following molecular chains of (i) to (iii):
(i) a polyethylene glycol chain having an average number of repeating oxyethylene units n in a range from 4 to 20;
(ii) a polyethylene glycol monoalkyl (C1-18) ether chain having an average number of repeating oxyethylene units n in a range from 4 to 9; and
(iii) a molecular chain represented by the following formula (1), the molecular chain having an average number of repeating oxyethylene oxypropylene units n in a range from 20 to 50 and a content of an oxyethylene unit in a range from 70 to 92% by mass:
R—(OEt)x-(OPr)y-A  (1)
wherein R represents a C1-18 alkyl group, A represents OH or NH2, Et represents an ethylene group, Pr represents a propylene group, and x+y=n,
a content of the oxyethylene unit derived from the monomer (A′) in the polymer is in a range from 50 to 90% by mass relative to a total mass of the polymer,
the polymer is (a) an A-B block copolymer or (b) an A-B-A block copolymer, having a polymer block A comprising the constitutional unit (A) and a polymer block B comprising the constitutional unit (B),
the polymer has a number average molecular weight in terms of polystyrene in a range from 4,000 to 15,000, as measured by gel permeation chromatography,
the polymer is water-soluble,
the polymer has a clouding point in a range from 50 to 80° C.,
the carboxy group or the amino group present in the monomer (B′) and introduced to the polymer is not neutralized and is not ionized in the polymer,
the aqueous pigment dispersion liquid has a pH in a range from 3.0 to 8.4,
the polymer adsorbs onto a surface of the pigment in the dispersion liquid, and
the aqueous pigment dispersion is configured to provide an emulsion-polymerized toner.