Method for preparing anti-bacterial oxide film on the surface of aluminum materials

Abstract

A method for preparing an anti-bacterial anodic oxide film on the surface of aluminum materials, comprising pretreatment, polishing, anodic oxidation, dyeing and sealing, wherein the surface of polished aluminum materials is smooth but has undulating waves and holes; in the dyeing after oxidation, a nano-sized dye is filled in the undulating waves and holes on the surface of aluminum materials, so if nano-silver is uniformly mixed in the dye in the process, the dye on the surface of aluminum materials will contain nano-silver finally and it will protect nano-silver from wearing during use; the dye-filled waves on the surface of aluminum materials are sealed via a sealing process finally, i.e., the dye is sealed in the surface of aluminum materials; at last, the surface of aluminum materials can be turned into desired colored patterns according to actual needs, and the nano-silver provides the anodic oxide film with anti-bacterial effect.

What is claimed is: 
     
         1 . A method for preparing an anti-bacterial oxide film on the surface of aluminum materials, characterized in that it comprises the following steps:
 1) pretreatment: remove oil on the workpiece and clean the workpiece;   2) polishing: put the clean workpiece in an acid solution for chemical polishing;   3) anodic oxidation: put the chemically-polished workpiece in an acid tank for anodic oxidation;   4) dyeing: put the anodized workpiece in a dye tank which contains a nano-dye, wherein the mass fraction of nano-silver in the dye is 3%-5% and its diameter is not more than 100 nm;   5) sealing: seal the dyed workpiece via a high-temperature hydration or inorganic salt sealing method, and take out the sealed workpiece and dry it after cleaning.   
     
     
         2 . The method for preparing an anti-bacterial oxide film on the surface of aluminum materials as claimed in  claim 1 , characterized in that an ultrasonic vibration plate is provided at the bottom of the dye tank in Step 4). 
     
     
         3 . The method for preparing an anti-bacterial oxide film on the surface of aluminum materials as claimed in  claim 1 , characterized in that a bubble generator is provided at the bottom of the dye tank in Step 4) and dry and clean air is introduced into the bubble generator. 
     
     
         4 . The method for preparing an anti-bacterial oxide film on the surface of aluminum materials as claimed in  claim 3 , characterized in that the diameter of the bubbles generated by the bubble generator is not more than 2 mm. 
     
     
         5 . The method for preparing an anti-bacterial oxide film on the surface of aluminum materials as claimed in  claim 1 , characterized in that the chemical polishing agent in Step 2) is a nitric acid solution. 
     
     
         6 . The method for preparing an anti-bacterial oxide film on the surface of aluminum materials as claimed in  claim 1 , characterized in that a sulfuric acid solution is used in the acid tank in Step 3). 
     
     
         7 . The method for preparing an anti-bacterial oxide film on the surface of aluminum materials as claimed in  claim 1 , characterized in that the workpiece is an aluminum or aluminum alloy workpiece. 
     
     
         8 . The method for preparing an anti-bacterial oxide film on the surface of aluminum materials as claimed in  claim 2 , characterized in that the workpiece is an aluminum or aluminum alloy workpiece. 
     
     
         9 . The method for preparing an anti-bacterial oxide film on the surface of aluminum materials as claimed in  claim 3 , characterized in that the workpiece is an aluminum or aluminum alloy workpiece. 
     
     
         10 . The method for preparing an anti-bacterial oxide film on the surface of aluminum materials as claimed in  claim 4 , characterized in that the workpiece is an aluminum or aluminum alloy workpiece. 
     
     
         11 . The method for preparing an anti-bacterial oxide film on the surface of aluminum materials as claimed in  claim 5 , characterized in that the workpiece is an aluminum or aluminum alloy workpiece. 
     
     
         12 . The method for preparing an anti-bacterial oxide film on the surface of aluminum materials as claimed in  claim 6 , characterized in that the workpiece is an aluminum or aluminum alloy workpiece.