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:
Oct. 18, 2022
Filed:
Oct. 15, 2019
Lg Chem, Ltd., Seoul, KR;
LG CHEM, LTD., Seoul, KR;
Abstract
According to the present invention, damage such as film tearing during a rolling process can be reduced by using, as a substrate for a flexible display, a polyimide film having the thickness of 5-10 μm, modulus of 3-8 GPa, the absolute value of out-of-plane retardation (Rth) of 200-600 nm, and a strain, at a tensile force of 100 MPa, of 10% or less. In addition, since the polyimide film has low residual stress with respect to inorganic substrates, the occurrence of defects during a TFT process is reduced. As a result, processing reliability for a flexible display can be improved. In addition, the saturated static electricity half-life of the polyimide film is controlled to be 250 seconds or more so as to minimize the voltage loss ratio of saturated static electricity and reduce the current drop during a TFT operation, and, as a result, enables a display having improved luminosity to be provided.