Acidic processes to prepare antimicrobial contact lenses

Abstract

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

1 . A method of preparing an antimicrobial lens comprising a metal salt, wherein said method comprising the steps of 
 (a) treating a cured lens, a solution comprising, consisting essentially of, or consisting of a salt precursor and an effective amount of an acidic substance, wherein the pH of said solution is less than about 7.0; and    (b) treating the lens of step (a) with a solution comprising, consisting essentially of, or consisting of a metal agent and an effective amount of an acidic substance, wherein the pH of said solution is less than about 7.0.    
     
     
         2 . The method of  claim 1  wherein the acidic substance is selected from the group consisting of acetic acid, hydrochloric acid, and sulfuric acid.  
     
     
         3 . The method of  claim 1  wherein the acidic substance is acetic acid.  
     
     
         4 . The method of  claim 1  wherein the effective amount of the acidic substance is about 0.01% to about 10%.  
     
     
         5 . The method of  claim 1  wherein the effective amount of the acidic substance is about 0.5%.  
     
     
         6 . The method of  claim 1  wherein the effective amount of the acidic substance is about 0.05%.  
     
     
         7 . The method of  claim 1  wherein the ph of the solution of steps (a) and (b) is about 2 to about 5.  
     
     
         8 . The method of  claim 1  wherein the ph of the solution of steps (a) and (b) is about 2 to about 4.  
     
     
         9 . The method of  claim 1  wherein the pH of the solution of steps (a) and (b) is about 3 to about 4.  
     
     
         10 . The method of  claim 1  wherein the salt precursor is selected from the group consisting of tetra-alkyl ammonium lactate, tetra-alkyl ammonium sulfate, tetra-alkyl ammonium chloride, tetra-alkyl ammonium, bromide, tetra-alkyl ammonium iodide, sodium chloride, sodium iodide, sodium bromide, lithium chloride, lithium sulfide, sodium sulfide, potassium sulfide, and sodium tetrachloro argentate.  
     
     
         11 . The method of  claim 1  wherein the salt precursor is selected from the group consisting of sodium chloride, sodium iodide, sodium bromide, lithium chloride, lithium sulfide, sodium sulfide, potassium sulfide, and sodium tetrachloro argentite.  
     
     
         12 . The method of  claim 1  wherein the salt precursor is sodium iodide.  
     
     
         13 . The method of  claim 1  wherein the metal agent is selected from the group consisting of silver iodide, silver chloride, and silver bromide.  
     
     
         14 . The method of  claim 1  wherein the salt precursor is selected from the group consisting of silver nitrate, silver triflate, and silver acetate.  
     
     
         15 . The method of  claim 1  wherein the salt precursor is silver acetate.  
     
     
         16 . A method of preparing an antimicrobial lens comprising a metal salt, wherein said method comprising the steps of 
 (a) treating a cured lens, a solution comprising, consisting essentially of, or consisting of a metal agent and an effective amount of an acidic substance, wherein the pH of said solution is less than about 7.0; and    (b) treating the lens of step (a) with a solution comprising, consisting essentially of, or consisting of a salt precursor and an effective amount of an acidic substance, wherein the pH of said solution is less than about 7.0.    
     
     
         17 . An antimicrobial lens comprising a metal salt, prepared by a method comprising the steps of 
 (a) treating a cured lens, a solution comprising a salt precursor and an effective amount of an acidic substance, wherein the pH of said solution is less than about 7.0; and    (b) treating the lens of step (a) with a solution comprising a metal agent and an effective amount of an acidic substance, wherein the pH of said solution is less than about 7.0.    
     
     
         18 . The antimicrobial lens of  claim 17  wherein the metal salt is silver iodide, the salt precursor is sodium nitrate, the metal agent is silver nitrate and the pH of the solutions of steps (a) and (b) is about 3-4.  
     
     
         19 . An antimicrobial lens comprising a metal salt, prepared by a method comprising the steps of 
 (a) treating a cured lens, a solution comprising a metal agent and an effective amount of an acidic substance, wherein the pH of said solution is less than about 7.0; and    (b) treating the lens of step (a) with a solution comprising, consisting essentially of, or consisting of a salt precursor and an effective amount of an acidic substance, wherein the pH of said solution is less than about 7.0.    
     
     
         20 . The antimicrobial lens of  claim 19  wherein the metal salt is silver iodide, the salt precursor is sodium nitrate, the metal agent is silver nitrate and the pH of the solutions of steps (a) and (b) is about 3-4.