Antiglare coating and articles

Abstract

The present invention relates to articles comprising an antiglare layer, coating compositions suitable for making antiglare layers, methods of making an antiglare article, and methods of making antiglare coating compositions. In some embodiments the article is a (e.g. illuminated) display article such as a touch screen. The antiglare layer comprises aggregate silica particle in a cured inorganic polymer matrix.

1 . A coating composition comprising an organosilane and flocculated silica particles ranging in size from 0.2 micrometers to 2 micrometers.  
     
     
         2 . The coating composition of  claim 1  wherein the coating composition comprises flocculated and colloidal silica particles at a concentration of less than 10 wt-% of the coating composition.  
     
     
         3 . The coating composition of  claim 1  wherein the coating composition comprises flocculated and colloidal silica particles at a concentration of less than 5 wt-% of the coating composition.  
     
     
         4 . The coating composition of  claim 1  wherein the coating composition comprises flocculated and colloidal silica particles at a concentration of less than 2 wt-% of the coating composition.  
     
     
         5 . The coating composition of  claim 1  wherein the coating composition comprises flocculated and colloidal silica particles at a concentration of less than 1 wt-% of the coating composition.  
     
     
         6 . The coating composition of  claim 1  wherein the coating composition comprises flocculated and colloidal silica particles at a concentration of less than 0.5 wt-% of the coating composition.  
     
     
         7 . The coating composition of  claim 1  wherein the organosilane comprises silicon alkoxides.  
     
     
         8 . The coating composition of  claim 7  wherein the silicon alkoxides are selected from tetraethoxysilane, methyltriethoxysilane, and mixtures thereof.  
     
     
         9 . The coating composition of  claim 1  wherein the coating composition is an alcohol-containing coating composition.  
     
     
         10 . A method of making an antiglare article comprising: 
 providing a transparent substrate;    coating the substrate with a coating composition comprising an organosilane and    flocculated silica particles ranging in size from 0.2 micrometers to 2 micrometers; and heating the coating composition.    
     
     
         11 . The method of  claim 10  wherein the substrate is selected from glass, polycarbonate, polymethylmethacrylate, and cellulose acetate butyrate.  
     
     
         12 . The method of  claim 10  wherein the substrate has a surface layer having a total surface area and the flocculated silica particles form surface structures that comprise at least 20% of the total surface area.  
     
     
         13 . The method of  claim 10  wherein the substrate has a surface layer having a total surface area and the flocculated silica particles form surface structures that comprise at least 30% of the total surface area.  
     
     
         14 . The method of  claim 10  wherein the substrate has a surface layer having a total surface area and the flocculated silica particles form surface structures that comprise at least 30% of the total surface area.  
     
     
         15 . A method of making an antiglare coating composition comprising: providing an inorganic polymer precursor and colloidal silica particles having a mean particle size ranging from 0.05 micrometers to 0.15 micrometers; and forming an inorganic polymer solution concurrently with flocculating colloidal silica aggregates.  
     
     
         16 . The method of  claim 15  wherein the colloidal inorganic oxide particle are present in an amount of less than 1.5 wt-%.  
     
     
         17 . The method of  claim 15  wherein the method comprises the addition of acid.  
     
     
         18 . The method of  claim 15  wherein the method comprises the addition of sodium acetate.  
     
     
         19 . The method of  claim 15  wherein the solution comprises flocculated silica particles ranging in size from 0.2 micrometers to 2 micrometers.