Antimicrobial chemical compositions

Abstract

Antimicrobial chemical compositions comprise an aluminum phosphate (AlP) solid dispersed within a binding polymer, wherein one or more bioactive materials are disposed within AlP forming a bioactive-AlP complex. The complex may comprise the bioactive material chemically bonded with the AlP, physically combined with the AlP, or a combination of both. The complex may be formed according to precipitation, condensation and sol-gel methods of forming. The complex is engineered to provide a controlled delivery of the bioactive material or a constituent thereof upon exposure to moisture to give a desired level of antimicrobial resistance to a film or composite formed from the composition of at least about 30 μg/m 2 , and may also provide a desired degree of corrosion resistance through the release of passivating phosphate anion. Such antimicrobial chemical compositions provide an improved degree of active, long-term resistance to a broad range of micro-organisms when compared to known antimicrobial chemical compositions.

1 - 16 . (canceled) 
     
     
         17 . A method for making a bioactive-aluminum phosphate complex comprising the steps of:
 forming an aluminum phosphate by combining an aluminum source, with a phosphate source in an aqueous solution at suitable pH to form a dispersion of aluminum phosphate particles; and   adding a bioactive material in a form to provide metal ions, wherein the step of adding is performed such that the metal ions are combined with the aluminum phosphate particles to form the bioactive-aluminum phosphate complex;   wherein the complex has a porosity engineered to provide a controlled release of the metal ions therefrom of from 10 to 1,000 ppm upon contact of the complex with moisture.   
     
     
         18 . The method as recited in  claim 17  wherein the complex has a porosity characterized by a BET surface area from about 2 to 250 m 2 /g. 
     
     
         19 . The method as recited in  claim 17  wherein the metal ions are chemically bonded to the aluminum phosphate particles. 
     
     
         20 . The method as recited in  claim 17  wherein the metal ions are selected from the group consisting of silver, copper, zinc, calcium, and combinations thereof. 
     
     
         21 . The method as recited in  claim 20  wherein the metal ions are silver ions. 
     
     
         22 . The method as recited in  claim 17  wherein the step of forming comprises combining aluminum hydroxide with phosphoric acid to form the dispersion of aluminum phosphate particles. 
     
     
         23 . The method as recited in  claim 17  wherein the complex has a porosity characterized by at least one of:
 a total intrusion volume of  0 . 5  to  2  mL/g; an average pore diameter of from about 0.02 to 0.6 μm; or 
 a BET surface area from about 2 to 250 m 2 /g. 
 
     
     
         24 . The method as recited in  claim 17  wherein the aluminum phosphate particles comprise amorphous aluminum phosphate. 
     
     
         25 . A method for making an antimicrobial chemical complex comprising a bioactive constituent in the form of metal ions, the method comprising the steps of:
 forming an aluminum phosphate by combining aluminum hydroxide with phosphoric acid in an aqueous solution at suitable pH to form a dispersion of aluminum phosphate particles, the aluminum phosphate comprising amorphous aluminum phosphate; and   adding a bioactive material during or after the step of forming, wherein the bioactive material comprises metal ions that combine with the aluminum phosphate particles to form the antimicrobial chemical complex capable of providing a controlled release of the metal ions upon exposure to moisture.   
     
     
         26 . The method as recited in  claim 25  wherein the antimicrobial chemical complex has a porosity characterized by at least one of:
 a total intrusion volume of  0 . 5  to  2  mL/g; 
 an average pore diameter of from about 0.02 to 0.6 μm; or 
 a BET surface area from about 2 to 250 m 2 /g. 
 
     
     
         27 . The method as recited in  claim 25  wherein, during the step of adding, the metal ions chemically bond to the aluminum phosphate particles. 
     
     
         28 . The method as recited in  claim 25  wherein the metal ions are silver ions, and wherein the controlled delivery of silver ions is from about 10 to 1,000 ppm. 
     
     
         29 . The method as recited in  claim 25  wherein the complex further comprises metal ions selected from the group consisting of copper, zinc, calcium, and combinations thereof. 
     
     
         30 . The method as recited in  claim 25  wherein, during the step of forming, first forming an acid solution phosphate solution by combining a first amount of the aluminum hydroxide with the phosphoric acid to form an acidic aluminum phosphate solution, and then subsequently combining the solution with further aluminum hydroxide to form the aluminum phosphate particles. 
     
     
         31 . The method as recited in  claim 30  wherein the step of adding takes place before the aluminum phosphate solution is combined with further aluminum hydroxide. 
     
     
         32 . A method for making an antimicrobial chemical composition comprising adding the antimicrobial chemical complex prepared according to  claim 25  to a binding polymer. 
     
     
         33 . The method as recited in  claim 32  wherein the complex as disposed in the binder comprises amorphous aluminum phosphate. 
     
     
         34 . (canceled) 
     
     
         35 . The method as recited in  claim 17  wherein the controlled delivery of the bioactive constituent is at least about 30 μg/m 2 . 
     
     
         36 . The method as recited in  claim 17  wherein the amount of the metal ions in the complex is in the range of from about  1  to 10 percent by weight of the total complex. 
     
     
         37 . The method as recited in  claim 32  comprising in the range of from about 0.1 to 2 weight percent of the metal ions based on the total weight of the chemical composition. 
     
     
         38 - 44 . (canceled)