	US 11,993,678 B2
	Polyamic acid, polyamic acid solution, polyimide, polyimide film, laminate and flexible device, and method for producing polyimide film
Mari Uno, Shiga (JP)
Assigned to KANEKA CORPORATION, Osaka (JP)
Filed by KANEKA CORPORATION, Osaka (JP)
Filed on Sep. 30, 2020, as Appl. No. 17/039,383.
Application 17/039,383 is a continuation of application No. PCT/JP2019/010122, filed on Mar. 12, 2019.
Claims priority of application No. 2018-069411 (JP), filed on Mar. 30, 2018.
Prior Publication US 2021/0024699 A1, Jan. 28, 2021
Int. Cl. C08G 73/10 (2006.01); B32B 27/08 (2006.01); B32B 27/28 (2006.01); C08J 5/18 (2006.01); H01L 27/12 (2006.01)

CPC C08G 73/1067 (2013.01) [B32B 27/08 (2013.01); B32B 27/281 (2013.01); C08G 73/1014 (2013.01); C08G 73/1032 (2013.01); C08J 5/18 (2013.01); H01L 27/1218 (2013.01)]

16 Claims

1. A polyamic acid which is a polyaddition reaction product of a diamine and a tetracarboxylic dianhydride,

wherein:

the diamine comprises 2,2′-bistrifluoromethylbenzidine,

the tetracarboxylic dianhydride comprises 3,3′,4,4′-biphenyltetracarboxylic dianhydride and 9,9′-(3,4′-dicarboxyphenyl)fluorenic dianhydride,

the 9,9′-(3,4′-dicarboxyphenyl)fluorenic dianhydride is comprised in an amount of 0.5 mol % or more and 10 mol % or less based on a total amount of the tetracarboxylic anhydride, and

an amount of the 2,2′-bistrifluoromethylbenzidine based on a total amount of the diamine is 90 mol % or more.