The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Apr. 19, 2022
Filed:
Feb. 05, 2018
Skc Co., Ltd., Gyeonggi-do, KR;
Sunhwan Kim, Incheon, KR;
Jin Woo Lee, Gyeonggi-do, KR;
Dae Seong Oh, Seoul, KR;
Dawoo Jeong, Gyeonggi-do, KR;
Kyu-Hun Kim, Seoul, KR;
SKC CO., LTD., Gyeonggi-do, KR;
Abstract
One embodiment may provide a method for producing a polyimide film, the method comprising the steps of: polishing the surface of a casting body; producing a gel sheet by casting a precursor on the polished surface of the casting body, and drying same; and producing a polyimide film by heat-treating the gel sheet, wherein the roughness of the polished surface of the casting body is 0.1 nm to 160 nm, and when the area of the casting body onto which the precursor is casted is partitioned by 1 cm×1 cm, the area corresponding to a defect reduction region is at least 90%, and the polyimide film has a yellowness of at most 3, a haze of at most 1%, a permeability of at least 88%, a modulus of at least 5.0 GPa and a surface hardness of at least HB.