Composite cover film and flexible display device

A composite cover film, comprising a polyimide layer, and a first hard coating and a first transparent optical adhesive layer disposed on two sides of the polyimide layer, respectively, wherein at least one of the first hard coating and the first transparent optical adhesive layer contains a nanoscale colorant, wherein the composite cover film further comprising a second hard coating disposed between the polyimide layer and the first transparent optical adhesive layer, wherein the second hard coating is formed by curing the following components:

• 0.001 wt % to 40 wt % of the nanoscale colorant;
• 10 wt % to 20 wt % of a polymer;
• 0.02 wt % to 5 wt % of an adhesive;
• at least one additive, each having an amount of no more than 5 wt %;
• and
• a first solvent,
• wherein the second hard coating has a thickness of 15 nm to 50 μm.

A composite cover film, comprising a polyimide layer, and a first hard coating and a first transparent optical adhesive layer disposed on two sides of the polyimide layer, respectively, wherein at least one of the first hard coating and the first transparent optical adhesive layer contains a nanoscale colorant, wherein the first transparent optical adhesive layer comprises an optical adhesive layer which is formed by curing the following components:

• 1 to 20 parts by weight of the nanoscale colorant;
• 60 to 80 parts by weight of an optical adhesive;
• at least one additive, each having an amount of 0.1 to 2 parts by weight;
• and
• 20 to 40 parts by weight of a solvent.