US Patent 8415404 Extended wear ophthalmic lens

An ophthalmic lens suited for extended-wear periods of at least one day on the eye without a clinically significant amount of corneal swelling and without substantial wearer discomfort. In one embodiment, an ophthalmic lens is a copolymerization product of at least one oxyperm, at least one ionoperm, and a crosslinker. In one embodiment, a lens has a tensile modulus of less than about 3.0 MPa, yet in another embodiment, the tensile modulus is between about 0.5 to about 1.5 MPa.