Patent ID: 7238750

Claim:
A hydrogel contact lens, comprising a polymer obtained by crosslinking or polymerized a solution of a prepolymer, wherein the prepolymer is a reaction product of an organic compound with a copolymer, wherein the copolymer includes first reactive groups and is a copolymerization product of a mixture comprising (a) at least one hydrophilic monomer having one first ethylenically unsaturated group; wherein the hydrophilic monomer is a monomer which, when polymerized, gives a homopolymer which is water-soluble or can absorb at least 10% by weight of water, (b) at least one crosslinker comprising two or more second ethylenically unsaturated groups; wherein said at least one crosslinker is a polysiloxane, a perfluoroalkyl polyether, or a polysiloxane/perfluoroalkyl polyether block copolymer, and (c) a chain transfer agent comprising a chain transfer group and a first reactive group, wherein the organic compound comprises a third ethylenically unsaturated group and a second reactive group which reacts with one of the first reactive groups of the copolymer to form a covalent linkage, wherein the prepolymer can be crosslinked or polymerized to form a polymeric material capable of forming a hydrogel when contacted with water.