Method for inhibiting stains on aluminum product surfaces

Abstract

A method for inhibiting the formation of stains, especailly water stains, on the exterior surface of aluminum alloy products. The method entails contacting the exterior surfaces of these products, particularly sheet or plate products, extrusions and/or forgings made from 5000 or 6000 Series aluminum alloys, with an organophosphonic or organophosphinic acid-derived material. Preferably, liquid forms of this material are added to an alcohol or water-based carrier solution, then sprayed, dipped, painted or rolled onto the surfaces of flat sheet or plate products to enhance their brightness. Other more complex shapes may be dipped into material baths.

What is claimed is:  
     
         1 . A method for inhibiting formation of stains on an exposed exterior of an aluminum alloy product, said method comprising: 
 (a) contacting the exposed exterior with a material that is capable of forming a hydrolytically stable Al—O—P bond therewith, said material selected from the group consisting of: an acidic aluminum phosphate salt; a phosphorous acid, a hypophosphorous acid; an organophosphonic or organophosphinic acid; a phosphate acid ester; an organophosphonic acid polymer or copolymer; and an organophosphate acid ester polymer or copolymer.    
     
     
         2 . The method of  claim 1  wherein the material consists essentially of an organophosphonic or organophosphinic acid.  
     
     
         3 . The method of  claim 2  wherein the material is a solid or semi-solid at room temperature and applied to the exposed exterior of the aluminum alloy product.  
     
     
         4 . The method of  claim 2  wherein the material is a liquid at room temperature and combined with a carrier selected from the group consisting of: an alcohol, a ketone, an ether, an aldehyde, an alkane, water and mixtures thereof.  
     
     
         5 . The method of  claim 4  wherein the material consists essentially of octadecylphosphonic acid and the carrier includes isopropanol.  
     
     
         6 . The method of  claim 4  wherein the material consists essentially of octylphosphonic acid and the carrier is selected from the group consisting of isopropanol, water and mixtures thereof.  
     
     
         7 . The method of  claim 4  wherein said exposed exterior is contacted with an aqueous solution consisting essentially of up to about 10 wt. % octadecylphosphonic acid, about 5-90 wt % isopropanol, a balance of water and impurities.  
     
     
         8 . The method of  claim 4  wherein said exposed exterior is contacted with an aqueous solution consisting essentially of up to about 10 wt. % octylphosphonic acid, about 5-90 wt % isopropanol, a balance of water and impurities.  
     
     
         9 . The method of  claim 4  wherein said exposed exterior is contacted with an aqueous solution consisting essentially of about 0.5-10 wt. % octylphosphonic acid, a balance of water and impurities.  
     
     
         10 . The method of  claim 4  wherein said contacting includes: spraying, dipping, painting or rolling material on said exposed exterior of said alloy product.  
     
     
         11 . The method of  claim 10  wherein said material is incorporated into a composition for surface treating said alloy product.  
     
     
         12 . The method of  claim 11  wherein said composition is selected from the group consisting of: a mill lubricant, a quenching solution, an intermediate rinse, an etching solution, a solvent, a surfactant, a cleaner, a polish, a post-rinse, a sealant and mixtures thereof.  
     
     
         13 . The method of  claim 2  wherein said alloy product is selected from the group consisting of sheet product, plate product, an extrusion and a forging.  
     
     
         14 . The method of  claim 13  wherein said sheet or plate product has at least one bright exterior surface and is selected from the group consisting of: trailer plate, rail car skin, a tool box, vehicle running board and tread plate.  
     
     
         15 . The method of  claim 13  wherein said sheet product is reflective lighting sheet.  
     
     
         16 . The method of  claim 13  wherein said extrusion is selected from the group consisting of: a truckbed rail, hydraulic tubing, window framing, tub and shower framing, and a greenhouse structural support.  
     
     
         17 . The method of  claim 13  wherein said alloy product is a vehicle wheel.  
     
     
         18 . The method of  claim 1  which further includes: (b) rinsing material from the exposed exterior.  
     
     
         19 . The method of  claim 18  which further includes: 
 (c) wiping said exposed exterior.  
 
     
     
         20 . The method of  claim 1  which further includes: (b) wiping material from the exposed exterior.  
     
     
         21 . The method of  claim 1  wherein said alloy product is made from a 1000, 3000, 5000 or 6000 Series aluminum alloy (Aluminum Association designations).  
     
     
         22 . The method of  claim 21  wherein said 5000 Series aluminum alloy is selected from the group consisting of: 5083, 5086, 5454, 5657, 5182, and 5456 aluminum (Aluminum Association designations).  
     
     
         23 . The method of  claim 21  wherein said 6000 Series aluminum alloy is selected from the group consisting of: 6061, 6111 and 6022 aluminum (Aluminum Association designations).  
     
     
         24 . A method for inhibiting the formation of water stains on an exposed exterior surface of a 5000 or 6000 Series aluminum alloy product, said method comprising: 
 (a) contacting the exterior surfaces with an organophosphonic or organophosphinic acid-derived material.    
     
     
         25 . The method of  claim 24  wherein said acid-derived material is a solid or semi-solid at room temperature and applied to said exterior surface.  
     
     
         26 . The method of  claim 24  wherein said acid-derived material is a liquid at room temperature and combined with a carrier selected from the group consisting of: an alcohol, a ketone, an ether, an aldehyde, an alkane, water and mixtures thereof.  
     
     
         27 . The method of  claim 26  wherein said acid-derived material consists essentially of octadecylphosphonic acid and said carrier includes isopropanol.  
     
     
         28 . The method of  claim 26  wherein said acid-derived material consists essentially of octylphosphonic acid and said carrier is selected from the group consisting of: isopropanol, water and mixtures thereof.  
     
     
         29 . The method of  claim 26  wherein said exterior surface is contacted with an aqueous solution consisting essentially of up to about 10 wt. % octadecylphosphonic acid, about 5-90 wt % isopropanol, the balance water and impurities.  
     
     
         30 . The method of  claim 26  wherein said exterior surface is contacted with an aqueous solution consisting essentially of up to about 10 wt. % octylphosphonic acid, about 5-90 wt % isopropanol, the balance water and impurities.  
     
     
         31 . The method of  claim 26  wherein said exterior surface is contacted with an aqueous solution consisting essentially of about 0.5-10 wt. % octylphosphonic acid, the balance water and impurities.  
     
     
         32 . The method of  claim 24  wherein said contacting includes: spraying, dipping, painting or rolling material onto said exterior surfaces.  
     
     
         33 . The method of  claim 24  wherein said acid-derived material is incorporated into a composition selected from the group consisting of: a mill lubricant, a quenching solution, an intermediate rinse, an etching solution, a solvent, a surfactant, a cleaner, a polish, a post-rinse, a sealant and mixtures thereof.  
     
     
         34 . The method of  claim 24  wherein said alloy product is selected from the group consisting of sheet product, plate product, an extrusion and a forging.  
     
     
         35 . The method of  claim 34  wherein said sheet or plate product has at least one bright exterior surface and is selected from the group consisting of: trailer plate, rail car skin, a tool box, vehicle running board and tread plate.  
     
     
         36 . The method of  claim 34  wherein said sheet product is reflective lighting sheet.  
     
     
         37 . The method of  claim 34  wherein said extrusion is selected from the group consisting of: a truckbed rail, hydraulic tubing, window framing, tub and shower framing, and a greenhouse structural support.  
     
     
         38 . The method of  claim 34  wherein said alloy product is a vehicle wheel.  
     
     
         39 . The method of  claim 24  which further includes: (b) rinsing material from the exposed exterior.  
     
     
         40 . The method of  claim 39  which further includes: 
 (c) wiping said exposed exterior.  
 
     
     
         41 . The method of  claim 24  which further includes: (b) wiping material from the exposed exterior.  
     
     
         42 . The method of  claim 24  wherein said 5000 Series aluminum alloy is selected from the group consisting of: 5083, 5086, 5454, 5657, 5182, and 5456 aluminum (Aluminum Association designations).  
     
     
         43 . The method of  claim 24  wherein said 6000 Series aluminum alloy is selected from the group consisting of: 6061, 6111 and 6022 aluminum (Aluminum Association designations).