Method for treating surface of aluminum can

Abstract

The purpose of the present invention is to provide a method for treating the surface of an aluminum can, in which an acidic treatment solution that is easy to handle can be used and the energy cost is sufficiently reduced. A method for treating the surface of an aluminum can, which comprises an alkali treatment step of treating the aluminum can with an alkaline treatment solution and an acid treatment step of treating the aluminum can that has been subjected to the alkali treatment step with an acidic treatment solution, wherein the etching amount to be employed in the alkali treatment step is less than 50 mg/m2. It is preferred that the alkaline treatment solution contains at least one ion selected from the group consisting of a sodium ion, a potassium ion and an ammonium ion.

1 . A method of treating a surface of an aluminum can, comprising:
 an alkaline treatment step of treating the aluminum can with an alkaline treatment liquid, and   an acid treatment step of treating the aluminum can after the alkaline treatment step with an acid treatment liquid,   wherein an amount of etching in the alkaline treatment step is less than 50 mg/m 2 .   
     
     
         2 . The method of treating a surface of an aluminum can according to  claim 1 , wherein
 the alkaline treatment liquid contains at least one selected from a group consisting of sodium ions, potassium ions and ammonium ions.   
     
     
         3 . The method of treating a surface of an aluminum can according to  claim 1 , wherein
 the alkaline treatment liquid is at 40 to 70° C., and   a treatment time of the aluminum can in the alkaline treatment step is 1 to 30 seconds.   
     
     
         4 . The method of treating a surface of an aluminum can according to  claim 1 , wherein
 the alkaline treatment liquid contains at least one selected from a group consisting of organic acid, a chelating agent, a dispersing agent and a surfactant.   
     
     
         5 . The method of treating a surface of an aluminum can according to  claim 1 , wherein
 the acid treatment liquid contains at least one selected from a group consisting of sulfuric acid, nitric acid and phosphoric acid, and contains 0.05 to 4 g/L of trivalent iron ions, and has a pH of 2 or less, and   a treatment temperature of the aluminum can in the acid treatment step is 30 to 65° C.   
     
     
         6 . The method of treating a surface of an aluminum can according to  claim 1 , wherein
 a treatment time of the aluminum can in the acid treatment step is 10 to 90 seconds.   
     
     
         7 . An aluminum can subjected to a surface treatment by the method of treating a surface of an aluminum can according to  claim 1 .