	US 12,110,401 B2
	Aqueous ink composition for writing instrument
Kousuke Ogura, Tokyo (JP); Akiko Hirayama, Tokyo (JP); and Kana Miyoshi, Tokyo (JP)
Assigned to MITSUBISHI PENCIL COMPANY, LIMITED, Tokyo (JP)
Appl. No. 16/965,529
Filed by MITSUBISHI PENCIL COMPANY, LIMITED, Tokyo (JP)
PCT Filed Jan. 21, 2019, PCT No. PCT/JP2019/001623 § 371(c)(1), (2) Date Jul. 28, 2020, PCT Pub. No. WO2019/146539, PCT Pub. Date Aug. 1, 2019.
Claims priority of application No. 2018-012759 (JP), filed on Jan. 29, 2018.
Prior Publication US 2021/0047529 A1, Feb. 18, 2021
Int. Cl. C09D 11/17 (2014.01); B01J 13/02 (2006.01); C09D 11/18 (2006.01); C09D 17/00 (2006.01)

CPC C09D 11/17 (2013.01) [B01J 13/02 (2013.01); C09D 11/18 (2013.01); C09D 17/00 (2013.01); C09D 17/001 (2013.01); C09D 17/005 (2013.01); C09D 17/007 (2013.01)]

5 Claims

1. An aqueous ink composition for a ballpoint pen, including inside a microcapsule pigment including, at least, a pigment and a medium of a fatty acid polyol ester,

wherein the fatty acid polyol ester is an ester constituted of a fatty acid and a polyol selected from the group consisting of ethylene glycol, diethylene glycol, triethylene glycol, polyethylene glycol, propylene glycol, dipropylene glycol, glycerin, sorbitan, sorbitol, pentaerythritol, dipentaerythritol, and trimethylolpropane, and

wherein a melting point of the fatty acid polyol ester is 40° C. or higher and 70° C. or lower.