US 12,454,625 B2
Aqueous ink
Kazuma Mori, Wakayama (JP); and Ryo Nakanishi, Wakayama (JP)
Assigned to KAO CORPORATION, Tokyo (JP)
Appl. No. 18/254,074
Filed by KAO CORPORATION, Tokyo (JP)
PCT Filed Nov. 25, 2021, PCT No. PCT/JP2021/043086
§ 371(c)(1), (2) Date May 23, 2023,
PCT Pub. No. WO2022/114035, PCT Pub. Date Jun. 2, 2022.
Claims priority of application No. 2020-197109 (JP), filed on Nov. 27, 2020.
Prior Publication US 2024/0002686 A1, Jan. 4, 2024
Int. Cl. C09D 11/322 (2014.01); B41J 2/01 (2006.01); B41J 2/21 (2006.01); C09D 11/033 (2014.01); C09D 11/037 (2014.01); C09D 11/107 (2014.01)
CPC C09D 11/322 (2013.01) [B41J 2/01 (2013.01); B41J 2/2107 (2013.01); C09D 11/033 (2013.01); C09D 11/037 (2013.01); C09D 11/107 (2013.01)] 19 Claims
 
1. An aqueous ink comprising a pigment, a fixing resin, and water, wherein:
the fixing resin comprises a constitutional unit derived from (meth)acrylic acid (A), a constitutional unit derived from a cycloalkyl (meth)acrylate (B), and a constitutional unit derived from an alkyl (meth)acrylate (C) whose homopolymer has a glass transition temperature (Tg) of not higher than 0° C.,
a content of the constitutional unit derived from the (meth)acrylic acid (A) is not less than 6% by mass and not more than 25% by mass on the basis of the whole constitutional units of the fixing resin,
a content of the constitutional unit derived from the cycloalkyl (meth)acrylate (B) is not less than 30% by mass and not more than 90% by mass on the basis of the whole constitutional units of the fixing resin, and
a glass transition temperature (Tg) of the fixing resin is not lower than −20° C. and not higher than 40° C.,
wherein the pigment is in a form of pigment-containing polymer particles, and the pigment-containing polymer particles are in a form of crosslinked polymer particles containing the pigment, the crosslinked polymer particles obtained by crosslinking the pigment-containing polymer particles with a crosslinking agent.