Wettable silicone hydrogel contact lenses and related compositions and methods
View Patent ↗Silicone hydrogel contact lenses having ophthalmically acceptable surface wettabilities are obtained from pre-extracted polymerized silicone hydrogel contact lens products having relatively large amounts of removable or extractable materials. The silicone hydrogel contact lenses can be obtained from non-polar resin based contact lens molds and without surface treatments or an interpenetrating polymeric network of a polymeric wetting agent. Related lens products, polymerizable compositions, and methods are also described.
1. A method for producing a silicone hydrogel contact lens having an ophthalmically acceptable surface wettability, comprising:
providing a polymerizable silicone hydrogel lens precursor composition in a contact lens shaped cavity of a non-polar resin contact lens mold, the polymerizable silicone hydrogel precursor composition comprising a silicon-containing component and a non-silicon containing component, the non-silicon containing- component comprising an N-vinyl pyrrolidone monomer, an N-vinyl-N-methyl acetamide monomer, an N-vinyl-N-ethyl acetamide monomer, an N-vinyl-N-ethyl formamide monomer, an N-vinyl formamide monomer, an N-2-hydroxyethyl vinyl carbamate monomer, or an N-carboxy-β-alanine N-vinyl ester monomer, or combinations thereof, and the contact lens mold comprising a first contact lens mold member and a second contact lens mold member assembled together;
polymerizing the polymerizable silicone hydrogel lens precursor composition in the non-polar resin contact lens mold to form a pre-extracted polymerized silicone hydrogel contact lens product having a dry weight, the pre-extracted silicone hydrogel contact lens product having a removable monomeric component in an amount of at least 10% (w/w) based on the dry weight of the pre-extracted polymerized silicone hydrogel contact lens product;
extracting and hydrating the pre-extracted polymerized silicone hydrogel contact lens product by contacting the pre-extracted polymerized silicone hydrogel contact lens product with an extraction media to produce a silicone hydrogel contact lens having a dry weight no greater than 90% of the dry weight of the pre-extracted polymerized silicone hydrogel contact lens product; and
packaging the silicone hydrogel contact lens in a contact lens package.
2. The method of claim 1 , wherein the removable monomeric component is present in an amount of at least 15% (w/w) based on the dry weight of the pre-extracted polymerized silicone hydrogel contact lens product.
3. The method of claim 1 , wherein the non-silicon containing component of the precursor composition comprises an N-vinyl pyrrolidone monomer.
4. The method of claim 1 , wherein the non-silicon containing component of the precursor composition comprises an N-vinyl pyrrolidone monomer, an N,N-dimethyl acrylamide monomer, or combinations thereof.
5. The method of claim 1 , wherein the non-silicon containing component of the precursor composition comprises an N-vinyl-N-methyl acetamide monomer.
6. The method of claim 1 , wherein the non-silicon containing component of the precursor composition further comprises an N,N-dimethyl acrylamide monomer, an 2-hydroxyethyl acrylate monomer, a glycerol methacrylate monomer, a 2-hydroxyethyl methacrylamide monomer, a polyethyleneglycol monomethacrylate monomer, or a polyethyleneglycol dimethacrylate monomer, or combinations thereof.
7. The method of claim 1 , wherein the non-silicon containing component includes a hydrophilic component in amount from about 10% to about 60% (w/w) based upon the weight of all reactive components of the precursor composition.
8. The method of claim 1 , wherein the extracting occurs at a temperature from about 20 degrees C. to about 100 degrees C.
9. The method of claim 1 , wherein the extraction media includes an alcohol.
10. The method of claim 1 , wherein the extraction media includes ethanol, methanol, or propanol.
11. The method of claim 1 , wherein the extraction media comprises water.
12. The method of claim 1 , wherein the precursor composition further includes a removable additive that does not become covalently bound to the polymerized lens product.
13. The method of claim 12 , wherein the additive is a diluent present in an amount from about 1% to about 60% (w/w) of the lens precursor composition.
14. The method of claim 1 , wherein the silicone hydrogel contact lens has extractable materials in an amount from about 0.1% to about 4% (w/w).
15. The method of claim 1 , wherein the silicone hydrogel contact lens has an oxygen permeability not less than 60 barrers.
16. The method of claim 1 , wherein the silicone hydrogel contact lens has an equilibrium water content no less than 30%.
17. The method of claim 16 , wherein the silicone hydrogel contact lens has an equilibrium water content from about 35% to about 65%.
18. The method of claim 1 , wherein the silicone hydrogel contact lens has an advancing contact angle less than about 120 degrees, a tensile modulus less than about 1.6 MPa, an ionoflux less than about 7×10 −3 mm 2 /min, an oxygen permeability of at least about 70 barrers, or a water content of at least about 30% by weight, or combinations thereof.
19. The method of claim 1 , wherein the polymerizable lens precursor composition comprises at least two reactive components that comprise monomers with different reactivity ratios.
20. The method of claim 1 , wherein the polymerizable lens precursor composition comprises a methacrylate phosphorylcholine monomer.
21. A silicone hydrogel contact lens comprising:
a lens body having an ophthalmically acceptable surface wettability and a dry weight no greater than 90% of the dry weight of the lens body prior to an extraction, wherein said lens body had at least 10% (w/w) of a removable monomeric component removed based on the dry weight of the lens body prior to removal, and wherein said lens body comprises a polymerized silicone hydrogel lens precursor composition comprising a silicon-containing component and a non-silicon containing component, the non-silicon containing- component comprising an N-vinyl pyrrolidone monomer, an N-vinyl-N-methyl acetamide monomer, an N-vinyl-N-ethyl acetamide monomer, an N-vinyl-N-ethyl formamide monomer, an N-vinyl formamide monomer, an N-2-hydroxyethyl vinyl carbamate monomer, or an N-carboxy-β-alanine N-vinyl ester monomer, or combinations thereof, and wherein the lens body is a cast molded element obtained from a non-polar resin contact lens mold.