A flexible display apparatus includes a flexible substrate, a display disposed over the flexible substrate, a thin film encapsulation layer disposed over an hermetically sealing the display, a phase delay layer disposed over the thin film encapsulation layer, and a polarizer film disposed over the phase delay layer, in which the phase delay layer comprises a first alignment film and a liquid crystal layer over the first alignment film, the liquid crystal layer having liquid crystal and reactive liquid crystal, where an amount of unhardened reactive liquid crystal in the liquid crystal layer is from about 100 ppm/inch2 to about 220 ppm/inch2.