US 11,739,228 B2
Graphene ink composition and method of preparing same
Myeong Gi Kim, Yeoju-si (KR); Seongmin Chin, Yeoju-si (KR); and Sung Min Hong, Yeoju-si (KR)
Assigned to UDUCK Advanced Materials, Yeoju-si (KR)
Appl. No. 16/756,459
Filed by UDUCK Advanced Materials, Yeoju-si (KR)
PCT Filed May 14, 2019, PCT No. PCT/KR2019/005534
§ 371(c)(1), (2) Date Apr. 15, 2020,
PCT Pub. No. WO2020/105821, PCT Pub. Date May 28, 2020.
Claims priority of application No. 10-2018-0144620 (KR), filed on Nov. 21, 2018; and application No. 10-2019-0001527 (KR), filed on Jan. 7, 2019.
Prior Publication US 2021/0222016 A1, Jul. 22, 2021
Int. Cl. C09D 11/037 (2014.01); C01B 32/182 (2017.01); B82Y 40/00 (2011.01)
CPC C09D 11/037 (2013.01) [B82Y 40/00 (2013.01); C01B 32/182 (2017.08)] 8 Claims
OG exemplary drawing
 
1. A method of preparing a graphene ink composition, the method comprising:
a step of preparing a first colloid in which charged chemically modified graphene is dispersed,
wherein the charged chemically modified graphene has a lateral size of 50 to 50000 nm and an average thickness of 2 nm or less, and
wherein the charged chemically modified graphene includes oxygen and nitrogen, and an atomic percent difference between the oxygen and the nitrogen is greater than 3 at %;
a step of preparing a second colloid in which a graphene flake is dispersed,
wherein the graphene flake has a lateral size of 0.3 to 50 μm and an average thickness of 2 to 20 nm and wherein the charged chemically modified graphene is different from the graphene flake; and
a step of preparing a graphene ink composition by mixing the first colloid, the second colloid, a binder and a solvent.