Preparation of antimicrobial contact lenses with reduced haze using swelling agents

Abstract

This invention relates to antimicrobial lenses containing metals and methods for their production.

What is claimed is:  
     
         1 - 15 . (canceled) 
     
     
         16 . An antimicrobial lens comprising, a metal salt, made by a method comprise the steps of
 (a) treating a cured lens, with a solution comprising salt precursor and a swelling agent,   (b) treating the lens of step (a) with solution comprising a swelling agent for an appropriate time, and   (c) treating the lens of step (b) with a solution comprising a metal agent and a swelling agent.   
     
     
         17 . The antimicrobial lens of  claim 16  wherein the swelling agent is aqueous isopropanol, or aqueous propylene glycol. 
     
     
         18 . The antimicrobial lens of  claim 16  wherein the swelling agent is about 30% to about 70% aqueous isopropanol. 
     
     
         19 . The antimicrobial lens of  claim 16  wherein the swelling agent is 50% aqueous isopropanol. 
     
     
         20 . The antimicrobial lens of  claim 16  wherein the swelling agent is aqueous propylene glycol. 
     
     
         21 . The antimicrobial lens of  claim 16  wherein the salt precursor is selected from the group consisting sodium chloride, sodium iodide, sodium bromide, sodium sulfide, lithium chloride, lithium iodide, lithium bromide, lithium sulfide, potassium bromide, potassium chloride, potassium sulfide, potassium iodide, rubidium iodide, rubidium bromide, rubidium chloride, rubidium sulfide, caesium iodide, caesium bromide, caesium chloride, caesium sulfide, francium iodide, francium bromide, francium chloride, francium sulfide, and sodium tetrachloro argentate 
     
     
         22 . The antimicrobial lens of  claim 16  wherein the salt precursor is sodium iodide. 
     
     
         23 . The antimicrobial lens of  claim 16  wherein the metal agent is selected from the group consisting of silver nitrate, silver triflate, or silver acetate, silver sulfate, silver tetrafluoroborate, silver sulfate, zinc acetate, zinc sulfate, copper acetate, and copper sulfate. 
     
     
         24 . The antimicrobial lens of  claim 16  wherein the metal agent is silver nitrate. 
     
     
         25 . The antimicrobial lens of  claim 16  wherein the appropriate time is about 10 to about 40 seconds. 
     
     
         26 . The antimicrobial lens of  claim 16  wherein the appropriate time is about 20 to about 30 seconds. 
     
     
         27 . The antimicrobial lens of  claim 16  wherein one or more of the solutions of steps (a), (b), and (c) comprise a dispersing agent. 
     
     
         28 . The antimicrobial lens of  claim 16 , wherein the dispersing agent is selected from the group consisting of polyvinylpyrrolidone, polyvinylalcohol and derivatives, glycerine, polyethylene oxide, poly(dimethyl acrylamide), poly(N-vinyl-N-methylacetamide), cysteine, methionine, sodium sulfide, sodium thiosulfate, and sodium thiocyanate. 
     
     
         29 . The antimicrobial lens of  claim 16  wherein the dispersing agent is polyvinylpyrrolidone K90. 
     
     
         30 . The antimicrobial lens of  claim 16  wherein the swelling agent is selected from the group consisting of extracting solvents as disclosed in U.S. Pat. No. 7,112,652.