US 12,466,967 B2
Aqueous ink composition for writing instruments
Kosuke Ogura, Shinagawa-ku (JP)
Assigned to MITSUBISHI PENCIL COMPANY, LIMITED, Shinagawa-ku (JP)
Appl. No. 17/770,127
Filed by MITSUBISHI PENCIL COMPANY, LIMITED, Shinagawa-ku (JP)
PCT Filed Oct. 22, 2020, PCT No. PCT/JP2020/039689
§ 371(c)(1), (2) Date Apr. 19, 2022,
PCT Pub. No. WO2021/085294, PCT Pub. Date May 6, 2021.
Claims priority of application No. 2019-196108 (JP), filed on Oct. 29, 2019.
Prior Publication US 2022/0363925 A1, Nov. 17, 2022
Int. Cl. C09D 11/00 (2014.01); C09D 11/17 (2014.01); C09D 11/18 (2006.01)
CPC C09D 11/17 (2013.01) [C09D 11/18 (2013.01)] 20 Claims
OG exemplary drawing
 
1. An aqueous ink composition suitable for a writing instrument, the composition comprising:
colored resin particles (A) having a pigment (p) encapsulated in the colored resin particles (A); and
colored resin particles (B) having a pigment (p) exposed on a surface,
wherein the colored resin particles (B) are produced by reducing an amount of a resin component used and/or increasing the pigment (p), compared to amounts for producing the colored resin particle (A).