High refractive index oxygen permeable contact lens system and method
A new high refractive index, oxygen permeable contact lens material and method for making the same. The material comprises an alkyl acrylate, a fluoro acrylate, a silicone acrylate, a polymerizable vinyl monomer having a substituted aromatic ring and/or heterocyclic ring structure, a multifunctional acrylate, and a polymerizable vinyl monomer having a heterocyclic ring structure.
1. A high refractive index oxygen permeable contact lens comprising a cross linked polymeric material comprising:
an alkyl acrylate present in an amount of between about 7% to about 15% by weight of the cross linked polymeric material;
a fluoro acrylate present in an amount of between about 1% to about 4% by weight of the cross linked polymeric material;
a silicone acrylate present in an amount of between about 10% to about 70% by weight of the cross linked polymeric material;
n-vinyl carbazole present in an amount of between about 20% to about 40% by weight of the cross linked polymeric material;
a cross-linking agent present in an amount of between about 0.1% to about 15% by weight of the cross linked polymeric material; and
n-vinyl pyrrolidone present in an amount of between about 2% to about 20% by weight of the cross linked polymeric material;
wherein the weight percentage of the n-vinyl pyrrolidone is about one third of the weight percentage of the n-vinyl carbazole; and
wherein the contact lens has an index of refraction that is greater than 1.51 and an oxygen permeability of greater than 22 Barrers.
2. A contact lens according to claim 1 , wherein the alkyl acrylate is present in an amount of between about 7% to about 12% by weight of the cross linked polymeric material.
3. A contact lens according to claim 2 , wherein the alkyl acrylate is methyl methacrylate.
4. A contact lens according to claim 1 , wherein the fluoro acrylate is present in an amount of between about 1% to about 3% by weight of the cross linked polymeric material.
5. A contact lens according to claim 4 , wherein the fluoro acrylate is trifluoroethyl methacrylate.
6. A contact lens according to claim 1 , wherein the silicone acrylate is present in an amount of between about 30% to about 60% by weight of the cross linked polymeric material.
7. A contact lens according to claim 6 , wherein the silicone acrylate is tris(trimethylsiloxy)-3-methacryloxypropylsilane.
8. A contact lens according to claim 1 , wherein the n-vinyl carbazole is present in an amount of between about 22% to about 36% by weight of the cross linked polymeric material.
9. A contact lens according to claim 1 , wherein the cross-linking agent is present in an amount of between about 5% to about 7% by weight of the cross linked polymeric material.
10. A contact lens according, to claim 9 , wherein the cross-linking agent is ethyleneglycol dimethacrylate.
11. A contact lens according to claim 1 , wherein the n-vinyl pyrrolidone is present in an amount between about 6% to about 13% by weight of the cross linked polymeric material.
12. A contact lens according to claim 1 , further comprising an initiator component present in an amount of about 0.8% by weight of the cross linked polymeric material.
13. A contact lens according to claim 12 , wherein the initiator component is azobisiosobutyronitrile.
14. A method of formulating a high refractive index oxygen-permeable contact lens comprising a cross linked polymeric material comprising the steps of:
combining by weight percent of the cross linked polymeric material:
about 7-15% methylmethacrylate;
about 1-4% trifluoroethylmethacrylate;
about 10-70% silicone acrylate;
about 20-40% n-vinyl carbazole;
about 0.1-15% ethylene glycol dimethacrylate;
about 2-20% by weight n-vinyl pyrrolidone; and
selecting relative weight percentages of n-vinyl pyrrolidone and n-vinyl carbazole according to a linear relationship between the n-vinyl pyrrolidone and n-vinyl carbazole components to achieve a contact lens material having an oxygen permeability (Dk) of at least 22 Barrers and a refractive index of at least 1.51,
wherein the weight percentage of the n-vinyl pyrrolidone is about one third of the weight percentage of the n-vinyl carbazole.
15. A method according to claim 14 , wherein the relative weight percentages of n-vinyl pyrrolidone and n-vinyl carbazole are determined by increasing the weight percentage of the n-vinyl pyrrolidone substantially proportionately with the increase in weight percentage of the n-vinyl carbazole.
16. A method according to claim 14 , wherein the relative weight percentages of n-vinyl pyrrolidone and n-vinyl carbazole are determined by decreasing the weight percentage of n-vinyl pyrrolidone substantially proportionately with the decrease in weight percentage of the n-vinyl carbazole.
17. A method according to claim 14 , wherein the method further comprises the step of adding an effective amount of light absorbing monomeric components.
18. A high refractive index oxygen permeable contact lens comprising a cross linked polymeric material comprising:
an alkyl acrylate present in an amount of between about 7% to about 15% by weight of the cross linked polymeric material;
a fluoro acrylate present in an amount of between about 1% to about 4% by weight of the cross linked polymeric material;
a silicone acrylate present in an amount of between about 10% to about 70% by weight of the cross linked polymeric material;
n-vinyl carbazole present in an amount of between about 20% to about 40% by weight of the cross linked polymeric material;
a cross-linking agent present in an amount of between about 0.1% to about 15% by weight of the cross linked polymeric material; and
n-vinyl pyrrolidone present in an amount of between about 2% to about 20% by weight of the linked polymeric material;
wherein the weight percentage of the n-vinyl pyrrolidone is adjusted to about one third of the weight percentage of the n-vinyl carbazole to achieve dissolution of the n-vinyl carbazole and to obtain an optically clear material; and
wherein the contact lens has an index of refraction that is greater than 1.51 and an oxygen permeability of greater than 22 Barrers.