Non-Metallic Nano/Micro Particles Coated with Metal, Process and Applications Thereof

Abstract

The present invention provides a simple and economical process for preparation of metal-coated non-metallic nano/micro particles. The nano/micro particles are composed of a core and metallic coat over the core using silver or other transition/noble metals. The core of the non-metallic nano/micro particles are selected from inorganic material such as silica, calcium carbonate, barium sulfate, or emulsion grade polyvinyl chloride and other polymers prepared by emulsion process including porous polymers. The metal coating is selected from the transition/noble metals such as copper, nickel, silver, palladium, platinum, osmium, ruthenium, rhodium, and such other metals and their combinations that are easily reducible to elemental metal.

1 . A nano/micro particle, comprising:
 (a) a core comprising a non-metallic material; and   (b) an overlayer comprising a transition/noble metal, wherein said overlayer comprises about 1 to 2 percent of said nano/micro particle by weight.   
   
   
       2 . The nano/micro particle of  claim 1 , wherein said non-metallic material of said core is selected from the group consisting of silica, calcium carbonate, barium sulfate, and polyvinyl chloride. 
   
   
       3 . The nano/micro particle of  claim 1 , wherein said non-metallic material of said core comprises an emulsion-grade polymer. 
   
   
       4 . The nano/micro particle of  claim 1 , wherein said non-metallic material of said core comprises a porous polymer. 
   
   
       5 . The nano/micro particle of  claim 1 , wherein said transition/noble metal of said overlayer is selected from the group consisting of copper, nickel, silver, palladium, platinum, ruthenium, gold, osmium, and rhodium. 
   
   
       6 . A method for preparing a nano/micro particle, comprising the method steps of:
 (a) dissolving a metallic salt in a liquid solvent;   (b) dispersing a quantity of non-metallic nano/micro particles in the solvent;   (c) evaporating the solvent to produce a slurry comprising a plurality of coated nano/micro particles;   (d) adding a reducing agent to the slurry; and   (e) drying the slurry.   
   
   
       7 .- 8 . (canceled) 
   
   
       9 . The method of  claim 6 , wherein said metallic salt comprises a metal selected from the group consisting of copper, nickel, silver, palladium, platinum, ruthenium, gold, osmium, and rhodium. 
   
   
       10 . The method of  claim 6 , wherein said non-metallic nano/micro particles comprise a material selected from the group consisting of silica, calcium carbonate, barium sulfate, and polyvinyl chloride. 
   
   
       11 . The method of  claim 6 , wherein said non-metallic nano/micro particles comprise an emulsion-grade polymer. 
   
   
       12 . The method of  claim 6 , wherein said non-metallic nano/micro particles comprise a porous polymer. 
   
   
       13 .- 54 . (canceled) 
   
   
       55 . An anti-microbial material, comprising:
 (a) a packaging material; and   (b) a plurality of nano/micro particles impregnated in said packaging material, each such nano/micro particle comprising a non-metallic core and a metallic overlayer, wherein said overlayer comprises about 1 to 2 percent of said nano/micro particle by weight.   
   
   
       56 . The anti-microbial packaging material of  claim 55 , wherein said plastic material is selected from a group consisting of polyethylene, polypropylene, polyvinyl chloride, and polystyrene. 
   
   
       57 . The anti-microbial packaging material of  claim 55 , wherein said plastic material is formed by one of extrusion, blowing, calendaring, compression, and injection molding. 
   
   
       58 . A method of producing an anti-microbial packaging material, comprising the steps of:
 (a) producing a plurality of nano/micro particles;   (b) mixing the plurality of nano/micro particles with plastic granules;   (c) heating the resulting mixture until the plastic granules are melted; and   (d) cooling the mixture to form a solid plastic material impregnated with nano/micro particles.   
   
   
       59 . The method of  claim 58 , wherein the plurality of nano/micro particles each comprise a non-metallic core and a metallic overlayer. 
   
   
       60 . (canceled) 
   
   
       61 . The method of  claim 59 , wherein the metallic overlayer comprises about 1 to 2 percent of each nano/micro particle by weight. 
   
   
       62 . The method of  claim 59 , wherein the non-metallic core is selected from the group consisting of silica, calcium carbonate, barium sulfate, and polyvinyl chloride. 
   
   
       63 . The method of  claim 59 , wherein the non-metallic core comprises an emulsion-grade polymer. 
   
   
       64 . The method of  claim 59 , wherein the non-metallic core comprises a porous polymer. 
   
   
       65 . (canceled) 
   
   
       66 . The method of  claim 59 , wherein the metallic overlayer comprises a metal selected from the group consisting of copper, nickel, silver, palladium, platinum, ruthenium, gold, osmium, and rhodium. 
   
   
       67 .- 101 . (canceled)