US Patent 10263216 Rollable display apparatus

A rollable display apparatus includes a rolling drum; and a flexible display panel comprising an end bonded to the rolling drum, the flexible display panel being windable around an outer circumferential surface of the rolling drum, the flexible display panel including a flexible substrate including a first surface on which a display device is arranged; and a first protection film over the first surface of the flexible substrate, the first protection film including a first layer including an elastic polymer, and a second layer on the first layer and having a smaller surface frictional force than the first layer, and the second layer includes a plurality of first grooves each indented in a depth direction of the second layer from a surface of the second layer.