US 11,655,337 B2
Polyimide precursor solution and method for producing same
Cheolmin Yun, Daejeon (KR); and Kyungjun Kim, Daejeon (KR)
Assigned to LG CHEM, LTD., Seoul (KR)
Appl. No. 16/76,260
Filed by LG CHEM, LTD., Seoul (KR)
PCT Filed Jul. 17, 2017, PCT No. PCT/KR2017/007658
§ 371(c)(1), (2) Date Aug. 7, 2018,
PCT Pub. No. WO2018/021747, PCT Pub. Date Feb. 1, 2018.
Claims priority of application No. 10-2016-0094851 (KR), filed on Jul. 26, 2016; and application No. 10-2017-0080993 (KR), filed on Jun. 27, 2017.
Prior Publication US 2021/0179780 A1, Jun. 17, 2021
Int. Cl. C08L 79/08 (2006.01); C08G 73/10 (2006.01); C08J 5/18 (2006.01); C08K 5/5415 (2006.01)
CPC C08G 73/106 (2013.01) [C08J 5/18 (2013.01); C08K 5/5415 (2013.01); C08L 79/08 (2013.01)] 8 Claims
1. A polyimide precursor solution comprising:
(a) a polyimide precursor comprising a repeating structure represented by the following Chemical Formulae 4a and 4b:

OG Complex Work Unit Chemistry
(b) an organic solvent having Log P as a positive value,
wherein the polyimide precursor solution has a dewetting ratio of 0% to 0.1% as defined by the following Formula 1:
Dewetting ratio (%)=[(A−B)/A]×100  [Formula 1]
A: The area of the polyimide precursor solution in the state that the polyimide precursor solution is completely coated on the substrate (100 mm×100 mm);
B: The area of the polyimide precursor solution or the polyimide (PI) film after the polyimide precursor solution or the polyimide film is rolled up from the end of the coated substrate;
wherein the repeating structure represented by Chemical Formula 4b is contained in the content of 13 mol % to 27 mol %, based on 100 mol % of the total content of repeating structures represented by Chemical Formulae 4a and 4b, and
wherein the organic solvent having a positive Log P value comprises diethylpropanamide (DEPA).