| abstract |
The polyester film according to the embodiment realized the elasticity required for the cover of the flexible display by increasing the increase rate of the stress at the initial stage of tension to a certain level or more.As a result, it was applied to the cover of the flexible display device, even when repeatedly folding a number of times. It can keep its original characteristics. Accordingly, the polyester film may be applied to a cover of a flexible display device, particularly a foldable display device, and exhibit excellent properties. |