Method for treating surface of metal product

Abstract

Disclosed herein is a method for treating the surface of a metal product, the method comprising the steps of: degreasing the surface of the metal product, and removing a material used to degrease the surface, followed by neutralization and washing; spraying either a mixture of ethanol (C 2 H 5 OH), acetone (CH 3 COCH 3 ) and water or alcohol onto the surface of the washed metal product; and forming an oxide layer on the surface of the metal product by firing or heat-treating the metal product resulting from the step of spraying.

What is claimed is: 
     
         1 . A method for treating the surface of a metal product, the method comprising the steps of:
 degreasing the surface of the metal product, and removing a material used to degrease the surface, followed by neutralization and washing;   spraying either a mixture of ethanol (C 2 H 5 OH), acetone (CH 3 COCH 3 ) and water or alcohol onto the surface of the washed metal product; and   forming an oxide layer on the surface of the metal product by firing or heat-treating the metal product resulting from the step of spraying.   
     
     
         2 . The method of  claim 1 , wherein the surface treatment solution in the spraying step is a mixture of ethanol (C 2 H 5 OH), acetone (CH 3 COCH 3 ) and water, wherein the amount of the ethanol is 1-50 times the volume of the water and the amount of the acetone is 0.05-1 time the volume of the ethanol. 
     
     
         3 . The method of  claim 1 , wherein the step of forming the oxide layer is carried out by directly firing the metal product resulting from the spraying step in a direct firing furnace at 200-260° C. for 10-15 seconds. 
     
     
         4 . The method of  claim 1 , wherein the step of forming the oxide layer is carried out by heat-treating the metal product resulting from the spraying step in heat treatment furnace at 150-200° C. for 5-20 minutes. 
     
     
         5 . The method of  claim 1 , wherein the method further comprises the steps of:
 washing treating the metal product resulting from the oxide layer forming step with ethanol, followed by drying; and   forming an electrodeposited layer on the oxide layer on the surface of the metal product resulting from the washing/drying step by an electrochromic process.   
     
     
         6 . The method of  claim 1 , wherein the method further comprises the steps of:
 washing treating the metal product resulting from the oxide layer forming step with ethanol, followed by drying; and   forming a coating layer on the oxide layer on the surface of the metal product resulting from the washing/drying step by a coating process.   
     
     
         7 . The method of  claim 1 , wherein the method further comprises the steps of:
 washing treating the metal product resulting from the oxide layer forming step with ethanol, followed by drying; and   forming a metal coating layer on the oxide layer on the surface of the metal product resulting from the washing/drying step by a dry coating process.