CONTACT LENS CONTAINING DEPROTECTED ULTRAVIOLET BLOCKERS
A method for preparing a contact lens containing an ultraviolet (UV) blocker is disclosed. The method involves (a) polymerizing a monomeric mixture comprising (i) one or more contact lens-forming comonomers, and (ii) one or more UV blockers comprising a phenolic group having a protected hydroxyl moiety and one or more ethylenically unsaturated reactive groups to obtain a polymerization product comprising the one or more UV blockers comprising a phenolic group having a protected hydroxyl moiety, and (b) deprotecting the protected hydroxyl moiety of the one or more UV blockers of the polymerization product.
1 . A method for preparing a contact lens containing an ultraviolet (UV) blocker, comprising:
(a) polymerizing under ultraviolet polymerization conditions a monomeric mixture comprising (i) one or more contact lens-forming comonomers, and (ii) one or more UV blockers comprising a phenolic group having a protected hydroxyl moiety and one or more ethylenically unsaturated reactive groups to obtain a polymerization product comprising the one or more UV blockers comprising a phenolic group having a protected hydroxyl moiety, and
(b) deprotecting the protected hydroxyl moiety of the one or more UV blockers of the polymerization product.
2 . The method according to claim 1 , wherein polymerizing the monomeric mixture under ultraviolet polymerization conditions is carried out for a time period of 5 to 50 minutes.
3 . The method according to claim 1 , wherein the one or more contact lens-forming comonomers are selected from the group consisting of one or more hydrophilic comonomers, one or more silicone-containing comonomers and mixtures thereof.
4 . The method according to claim 1 , wherein the one or more UV blockers comprising a phenolic group having a protected hydroxyl moiety and one or more ethylenically unsaturated reactive groups comprise a benzotriazole compound having a structure of Formula I:
wherein each R is independently hydrogen, a halogen, an —O— group, a nitro group, a nitrile group, a substituted or unsubstituted alkoxy group, a substituted or unsubstituted hydroxyl group, a substituted or unsubstituted amine group, a substituted or unsubstituted carbonyl group, and a substituted or unsubstituted hydrocarbyl group, R* is hydrogen or a substituted or unsubstituted hydrocarbyl group, R** is an ethylenically unsaturated reactive group and PG is a protected hydroxyl moiety.
5 . The method according to claim 4 , wherein R and R* are each hydrogen and R** is a (meth)acrylate-containing reactive end group.
6 . The method according to claim 4 , wherein R** is positioned on the aromatic ring in the para position relative to the protected hydroxyl moiety.
7 . The method according to claim 4 , wherein the protecting group of the protected hydroxyl moiety comprises one of a trialkylsilane group, a branched alkyloxycarbonyl group, a vinyloxycarbonyl group, a methoxymethyl group, an ethoxycarbonyloxy group and a di-t-alkyl decarbonate group.
8 . The method according to claim 1 , wherein the monomeric mixture comprises:
about 10 wt. % to about 90 wt. %, based on the total weight of the monomeric mixture, of the one or more contact lens-forming comonomers; and
about 0.1 wt. % to 5 wt. %, based on the total weight of the monomeric mixture, of the one or more UV blockers.
9 . The method according to claim 1 , wherein the monomeric mixture further comprises one or more blue light blockers comprising a phenolic group comprising a protected hydroxyl moiety and one or more ethylenically unsaturated reactive groups, and the method further comprises deprotecting the protected hydroxyl moiety of the one or more blue light blockers.
10 . The method according to claim 9 , wherein the one or more blue light blockers are represented by an acridone compound having a structure of Formula II:
wherein each R is independently hydrogen, a halogen, an —O— group, a nitro group, a nitrile group, a substituted or unsubstituted alkoxy group, a substituted or unsubstituted hydroxyl group, a substituted or unsubstituted amine group, a substituted or unsubstituted carbonyl group, and a substituted or unsubstituted hydrocarbyl group, R* is hydrogen or a substituted or unsubstituted hydrocarbyl group, R** is an ethylenically unsaturated reactive group and PG is a protected hydroxyl moiety.
11 . The method according to claim 10 , wherein R and R* are each hydrogen and R** is a (meth)acrylate-containing reactive end group, R** is positioned on the aromatic ring in the para position relative to the protected hydroxyl moiety, and the protecting group of the protected hydroxyl moiety comprises one of a trialkylsilane, a branched alkyloxycarbonyl, a vinyloxycarbonyl, a methoxymethyl, and a di-t-alkyl dicarbonate.
12 . The method according to claim 9 , wherein the monomeric mixture comprises:
about 0.1 wt. % to about 2 wt. %, based on the total weight of the monomeric mixture, of the one or more blue light blockers.
13 . The method according to claim 1 , wherein the monomeric mixture further comprises one or more crosslinking agents.
14 . The method according to claim 1 , wherein deprotecting the protected hydroxyl moiety of the one or more UV blockers of the polymerization product comprises subjecting the polymerization product to an extraction process.
15 . The method according to claim 14 , wherein the extraction process comprises immersing the polymerization product in a series of solvent solutions.
16 . The method according to claim 14 , further comprising autoclaving the polymerization product after the extraction process.
17 . The method according to claim 1 , wherein deprotecting the protected hydroxyl moiety of the one or more UV blockers of the polymerization product comprises autoclaving the polymerization product.
18 . The method according to claim 1 , wherein the contact lens demonstrates sufficient blocking of UV to meet at least FDA Class I specifications for UV blocking.
19 . A contact lens comprising one or more UV blockers comprising a phenolic group comprising a deprotected hydroxyl moiety which is an extracted and/or autoclaved, ultraviolet cured polymerization product of a monomeric mixture comprising (a) one or more contact lens-forming comonomers, and (b) one or more ultraviolet (UV) blockers comprising a phenolic group having a protected hydroxyl moiety and one or more ethylenically unsaturated reactive groups.
20 . The contact lens according to claim 19 , wherein the one or more contact lens-forming comonomers are selected from the group consisting of one or more hydrophilic comonomers, one or more silicone-containing comonomers and mixtures thereof, and the one or more UV blockers comprising a phenolic group having a protected hydroxyl moiety and one or more ethylenically unsaturated reactive groups comprise a benzotriazole compound having a structure of Formula I:
wherein each R is independently hydrogen, a halogen, an —O— group, a nitro group, a nitrile group, a substituted or unsubstituted alkoxy group, a substituted or unsubstituted hydroxyl group, a substituted or unsubstituted amine group, a substituted or unsubstituted carbonyl group, and a substituted or unsubstituted hydrocarbyl group, R* is hydrogen or a substituted or unsubstituted hydrocarbyl group, R** is an ethylenically unsaturated reactive group and PG is a protected hydroxyl moiety.