	US 11,897,770 B2
	Method for producing densified carbon nanotube fiber
Hyeon Su Jeong, Jeollabuk-do (KR); Seung Min Kim, Jeollabuk-do (KR); Sook Young Moon, Jeollabuk-do (KR); and Dong Myeong Lee, Jeollabuk-do (KR)
Assigned to KOREA INSTITUTE OF SCIENCE AND TECHNOLOGY, Seoul (KR)
Filed by KOREA INSTITUTE OF SCIENCE AND TECHNOLOGY, Seoul (KR)
Filed on Nov. 23, 2020, as Appl. No. 17/101,198.
Claims priority of application No. 10-2020-0046900 (KR), filed on Apr. 17, 2020.
Prior Publication US 2021/0323826 A1, Oct. 21, 2021
Int. Cl. D01D 5/00 (2006.01); C01B 32/168 (2017.01); D01F 9/12 (2006.01); D01D 5/06 (2006.01); D01F 11/10 (2006.01)

CPC C01B 32/168 (2017.08) [D01D 5/0046 (2013.01); D01D 5/06 (2013.01); D01F 9/12 (2013.01); C01P 2004/03 (2013.01); C01P 2006/10 (2013.01); D01F 11/10 (2013.01)]

9 Claims

1. A method for producing densified carbon nanotube fiber, the method comprising:

preparing carbon nanotube fiber;

swelling the carbon nanotube fiber by applying an acid solution thereto, and stretching the carbon nanotube fiber;

coagulating the stretched carbon nanotube fiber so as to remove the acid solution present therein; and

drying the coagulated carbon nanotube fiber;

wherein in the preparing the carbon nanotube fiber, carbon nanotube fiber having a linear density equal to or greater than 5 tex is prepared, and

in the swelling and stretching the carbon nanotube fiber, the carbon nanotube fiber is stretched to a stretching ratio greater than 80% but less than or equal to 200%.