According to one aspect, a composite film may include a substrate, and a protection coating overlying the substrate. The protection coating may include a urethane acrylate 6-functional oligomer, and a urethane acrylate 2-functional oligomer. The protection coating may further include a urethane acrylate oligomer ratio UAC6/UAC2 of at least about 0.5 and not greater than about 3, where UAC6 is equal to the content of the urethane acrylate 6-functional oligomer in wt. % for a total weight of the protection coating and UAC2 is equal to the content of the urethane acrylate 2-functional oligomer in wt. % for a total dry weight of the protection coating.