Silicone hydrogel contact lenses
View Patent ↗Silicone hydrogel contact lenses that are derived from a polymerizable composition including at least one siloxane monomer and at least one hydrophobic ethylene glycol methyl ether methacrylate-containing monomer, or at least one hydrophilic vinyl ether-containing monomer, or both, wherein, when the at least one hydrophobic ethylene glycol methyl ether methacrylate-containing monomer is present in the polymerizable composition, it is present in an amount of from 1 to 20 unit parts by weight, and when the at least one hydrophilic vinyl ether-containing monomer is present in the polymerizable composition, it is present in an amount of from 1 to 20 unit parts by weight, are described. Batches of silicone hydrogel contact lenses and methods of making silicone hydrogel contact lenses are also described.
1. A silicone hydrogel contact lens, comprising:
a polymeric lens body that is the reaction product of a polymerizable composition, said polymerizable composition comprising
(a) at least one siloxane monomer; and
(b) ethylene glycol methyl ether methacrylate (EGMA) in an amount of from 1 to 20 unit parts by weight;
wherein the polymerizable composition further comprises methyl methacrylate (MMA), and a ratio of unit parts by weight of MMA to unit parts by weight of EGMA present in the polymerizable composition is from about 6:1 to about 1:1.
2. The silicone hydrogel contact lens of claim 1 , wherein the polymerizable composition further comprises at least one hydrophilic vinyl ether-containing monomer.
3. The silicone hydrogel contact lens of claim 1 , wherein the polymerizable composition further comprises at least one vinyl-containing cross-linking agent.
4. The silicone hydrogel contact lens of claim 1 , wherein the polymerizable composition further comprises at least one acrylate or methacrylate-containing cross-linking agent.
5. The contact lens of claim 1 , wherein the at least one siloxane monomer is a dual-end methacrylate end-capped polydimethylsiloxane monomer.
6. The contact lens of claim 1 , wherein the at least one siloxane monomer comprises a first siloxane monomer having a molecular weight of from 400 daltons to 700 daltons, and a second siloxane monomer having a molecular weight greater than about 7,000 daltons.
7. The contact lens of claim 1 , wherein the at least one siloxane monomer comprises a monofunctional siloxane monomer represented by formula (3):
wherein m of formula (3) represents one integer from 3 to 10, n of formula (3) represents one integer from 1 to 10, R 1 of formula (3) is an alkyl group having from 1 to 4 carbon atoms, and each R 2 of formula (3) is independently either a hydrogen atom or a methyl group.
8. The contact lens of claim 7 , wherein in the siloxane monomer of formula (3), m of formula (3) is 4, n of formula (3) is 1, R 1 of formula (3) is a butyl group, and each R 2 of formula (3) is independently either a hydrogen atom or a methyl group.
9. The contact lens of claim 1 , wherein the at least one siloxane monomer comprises a bifunctional siloxane monomer represented by formula (4):
wherein R 1 of formula (4) is selected from either hydrogen atom or a methyl group; R 2 of formula (4) is selected from either of hydrogen atom or a hydrocarbon group having 1 to 4 carbon atoms; m of formula (4) represents an integer of from 0 to 10; n of formula (4) represents an integer of from 4 to 100; a and b represent integers of 1 or more; a+b is equal to 20-500; b/(a+b) is equal to 0.01-0.22; and the configuration of siloxane units includes a random configuration.
10. The contact lens of claim 9 , wherein in the siloxane monomer of formula (4), m of formula (4) is 0, n of formula (4) is an integer from 5 to 15, a is an integer from 65 to 90, b is an integer from 1 to 10, R 1 of formula (4) is a methyl group, and R 2 of formula (4) is either a hydrogen atom or a hydrocarbon group having 1 to 4 carbon atoms.
11. The contact lens of claim 1 , wherein the polymerizable composition comprises a first siloxane monomer and a second siloxane monomer, and a ratio of unit parts of the first siloxane monomer present in the polymerizable composition to unit parts of the second siloxane monomer present in the polymerizable composition is at least 2:1.
12. The contact lens of claim 1 , wherein the polymerizable composition further comprises at least one hydrophilic amide monomer having one N-vinyl group.
13. The contact lens of claim 12 , wherein the at least one hydrophilic amide monomer having one N-vinyl group is present in the polymerizable composition in an amount from about 10 to about 60 unit parts by weight.
14. A batch of silicone hydrogel contact lenses, comprising a plurality of the contact lens recited in claim 1 , wherein the batch of silicone hydrogel contact lenses has, when fully hydrated, an average equilibrium water content (EWC) from about 30% wt/wt to about 70% wt/wt, or an average oxygen permeability of at least 55 barrers, or a tensile modulus from about 0.2 MPa to about 0.9 MPa, or any combination thereof, based on averages of values determined for at least 20 individual lenses of the batch.
15. A method of manufacturing a silicone hydrogel contact lens, comprising:
providing a polymerizable composition, said polymerizable composition comprising
(a) at least one siloxane monomer; and
(b) ethylene glycol methyl ether methacrylate (EGMA) in an amount of from 1 to 20 unit parts by weight;
polymerizing the polymerizable composition in a contact lens mold assembly to form a polymeric contact lens body;
contacting the polymeric contact lens body with a washing liquid to remove extractable material from the polymeric contact lens body; and
packaging the polymeric contact lens body in a contact lens packaging solution in a contact lens package,
wherein the polymerizable composition further comprises methyl methacrylate (MMA), and a ratio of unit parts by weight of MMA to unit parts by weight of EGMA present in the polymerizable composition is from about 6:1 to about 1:1.
16. The method of claim 15 , wherein the washing liquid comprises a volatile organic solvent.
17. The method of claim 15 , wherein the washing liquid is free of a volatile organic solvent, and the polymeric contact lens body is not contacted by a volatile organic solvent during its manufacturing process.
18. The silicone hydrogel contact lens of claim 1 , wherein the ratio is at least 2:1.
19. The method of claim 15 , wherein the ratio is at least 2:1.
20. The silicone hydrogel contact lens of claim 1 , wherein the polymerizable composition is substantially free of a hydrophilic vinyl ether containing monomer.