Contact lens having improved dimensional stability
AssigneeBenz Research and Development Corporation
InventorsPatrick H. Benz, Jose A. Ors
Life of this patent
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Abstract
A contact lens and a contact lens blank having increased dimensional stability are constructed from a copolymer of 2,3-dihydroxypropyl methacrylate and 2-hydroxyethyl methacrylate, wherein the copolymer of 2,3-dihydroxypropyl methacrylate and 2-hydroxyethyl methacrylate has either an absolute water balance ratio greater than 8 or a relative water balance ratio greater than 2 relative to a polymer of 2-hydroxyethyl methacrylate.
Claims42
A soft contact lens having increased dimensional stability, consisting essentially of a copolymer of 2,3-dihydroxypropyl methacrylate and 2-hydroxyethyl methacrylate and wherein said copolymer of 2,3-dihydroxypropyl methacrylate and 2-hydroxyethyl methacrylate has an absolute water balance ratio greater than 8.
A process for forming a soft contact lens having increased dimensional stability comprising:
- (A) providing a polymerization reaction mixture which consists essentially of 2,3-dihydroxypropyl methacrylate as a monomer with 2-hydroxyethyl methacrylate as a comonomer;
- (B) polymerizing said reaction mixture to form a copolymer;
- (C) mechanically forming an optical contact lens from said polymer;
- and
- (D) hydrating said lens subsequent to mechanical formation
- to furnish a soft contact lens having an absolute water balance ratio greater than 8.
A soft contact lens blank having increased dimensional stability, consisting essentially of a copolymer of 2,3-dihydroxypropyl methacrylate and 2-hydroxyethyl methacrylate and wherein said copolymer of 2,3-dihydroxypropyl methacrylate and 2-hydroxyethyl methacrylate has a relative water balance ratio greater than 2 relative to a polymer of 2-hydroxyethyl methacrylate.
A process for forming a soft contact lens blank having increased dimensional stability comprising:
- (A) providing a polymerization reaction mixture which consists essentially of 2,3-dihydroxypropyl methacrylate as a monomer with 2-hydroxyethyl methacrylate as a comonomer;
- (B) polymerizing said reaction mixture to form a copolymer;
- and
- (C) mechanically forming an optical contact lens blank from said polymer
- to furnish a soft contact lens blank having a relative water balance ratio greater than 2 relative to a polymer of 2-hydroxyethyl methacrylate.
A process for forming a molded or partially molded soft contact lens having increased dimensional stability, comprising the steps of:
- (A) providing a polymerization reaction mixture which consists essentially of 2,3-dihydroxypropyl methacrylate as a monomer with 2-hydroxyethyl methacrylate as a comonomer;
- (B) polymerizing said reaction mixture in a mold to form a copolymer optical contact lens or partial contact lens;
- and
- (C) hydrating said lens subsequent to said forming step
- to furnish a soft contact lens having an absolute water balance ratio greater than 8.
Dependencies are inferred from the claim text.