Surface dyeing process for metal articles

Abstract

A surface treatment process for a metal article includes the following steps. Firstly, a metal article is provided. Secondly, the metal article is anodized to form an anodic oxide layer on a surface thereof. Thirdly, the surface of the metal article is rinsed. Fourthly, the surface of the metal article is dyed. Fifthly, the now-dyed anodic oxide layer of the metal article is sealed. Finally, the metal article is rinsed using an acetic acid solution.

1 . A surface treatment process for a metal article, comprising the steps:
 providing a metal article;   anodizing the metal article to form an anodic oxide layer on a surface of the metal article;   rinsing the surface of the metal article;   dyeing the surface of the metal article;   sealing the dyed anodic oxide layer of the metal article; and   after the step of sealing, rinsing the metal article by using an acetic acid solution.   
     
     
         2 . The surface treatment process as claimed in  claim 1 , wherein the metal article is comprised of at least one of aluminum, magnesium, and titanium. 
     
     
         3 . The surface treatment process as claimed in  claim 1 , further comprising a pretreatment process before the step of anodizing the metal article, the pretreatment process including a step of degreasing the surface of the metal article and a step of polishing the surface of the metal article. 
     
     
         4 . The surface treatment process as claimed in  claim 3 , wherein the step of degreasing the surface of the metal article is carried out in an alkali-based cleaning solution. 
     
     
         5 . The surface treatment process as claimed in  claim 3 , wherein the step of polishing the surface of the metal article is carried out in a chemical polishing solution, which contains 80 wt. % to 90 wt. % phosphoric acid, 3 wt. % to 5 wt. % sulfuric acid, and 6 wt. % to 7 wt. % nitric acid. 
     
     
         6 . The surface treatment process as claimed in  claim 3 , further comprising a step of dipping the metal article in a chromic acid solution after the step of polishing. 
     
     
         7 . The surface treatment process as claimed in  claim 1 , wherein the anodizing of the metal article involves a cleaning step and an electrolysis step, the cleaning step being carried out in an alkaline solution, the electrolysis step being carried out in an electrolyte containing 0.2˜1.0 wt. % phosphoric acid and using the metal article as an anode. 
     
     
         8 . The surface treatment process as claimed in  claim 7 , wherein during the electrolysis step, the metal article is anodized in the electrolyte at a current density of 10˜50 milliamperes per square centimeter, with a direct current in a range from 20 volts to 60 volts applied thereto. 
     
     
         9 . The surface treatment process as claimed in  claim 1 , wherein the anodizing of the metal article involves a cleaning step and an electrolysis step, the cleaning step being carried out in an alkaline solution, the electrolysis step being carried out in an electrolyte containing sulfuric acid at a concentration in an approximate range from 100 g/l to 200 g/l. 
     
     
         10 . The surface treatment process as claimed in  claim 9 , wherein during the electrolysis step, the metal article is anodized in the electrolyte at a current density of 10˜20 milliamperes per square centimeter and at a temperature in an approximate range from 20° C. to 26° C. 
     
     
         11 . The surface treatment process as claimed in  claim 1 , wherein the dyeing of the surface of the metal article is carried out in a dye solution containing an organic dye at a concentration in an approximate range from of 1 g/l to 10 g/l. 
     
     
         12 . The surface treatment process as claimed in  claim 1 , wherein the sealing step is carried out in a nickel salt solution comprising at least one of nickel acetate and nickel fluoride. 
     
     
         13 . The surface treatment process as claimed in  claim 1 , wherein the acetic acid solution has a concentration in an approximate range from 0.3 wt % to 0.6 wt %. 
     
     
         14 . The surface treatment process as claimed in  claim 1 , wherein during the rinsing of the metal article, the acetic acid solution is maintained at a temperature in an approximate range from 50° C. to 70° C. 
     
     
         15 . A process of treating an anodic oxide layer of an anodized metal article, comprising the steps:
 dyeing the anodic oxide layer of the anodized metal article;   sealing the anodic oxide layer of the anodized metal article to yield a sealed, anodized metal article; and   rinsing the sealed, anodized metal article using an acetic acid solution.   
     
     
         16 . The surface treatment process as claimed in  claim 15 , wherein the acetic acid solution has a concentration in an approximate range from 0.3 wt % to 0.6 wt %. 
     
     
         17 . The surface treatment process as claimed in  claim 15 , wherein the acetic acid solution is maintained at a temperature in an approximate range from 50° C. to 70° C.