Metal surface treatment liquid for cation electrodeposition coating

Abstract

A surface treatment with a zirconium ion that enables sufficient throwing power, and superior anti-corrosion properties to be exhibited when thus surface treated metal base material is subjected to cation electrodeposition coating is provided. A metal surface treatment liquid for cation electrodeposition coating includes zirconium ions and tin ions, and has a pH of 1.5 to 6.5, in which: the concentration of zirconium ions is in the range of 10 to 10,000 ppm; and the content of the tin ions to the zirconium ions is 0.005 to 1 on a mass basis. Furthermore, a polyamine compound, copper ions, fluorine ions, and a chelate compound may also be included.

1 - 13 . (canceled) 
     
     
         14 . A metal surface treatment liquid for cation electrodeposition coating comprising zirconium ions and tin ions, and having a pH of 1.5 to 6.5, wherein:
 a concentration of zirconium ions is in the range of 10 to 10,000 ppm; and   a concentration ratio of the tin ions to the zirconium ions is in the range of 0.005 to 1 on a mass basis.   
     
     
         15 . A metal surface treatment liquid for cation electrodeposition coating according to  claim 14  further comprising a polyamine compound. 
     
     
         16 . A metal surface treatment liquid for cation electrodeposition coating according to  claim 15  wherein said polyamine compound is a condensate of aminosilane hydrolysate. 
     
     
         17 . A metal surface treatment liquid for cation electrodeposition coating according to  claim 14 , further comprising copper ions. 
     
     
         18 . A metal surface treatment liquid for cation electrodeposition coating according to  claim 15 , further comprising copper ions. 
     
     
         19 . A metal surface treatment liquid for cation electrodeposition coating according to  claim 14 , further comprising fluorine ions, wherein the amount of free fluorine ions at a pH of 3.0 is in the range of 0.1 to 50 ppm. 
     
     
         20 . A metal surface treatment liquid for cation electrodeposition coating according to  claim 14 , further comprising a chelate compound. 
     
     
         21 . A metal surface treatment liquid for cation electrodeposition coating according to  claim 20 , wherein the chelate compound is sulfonic acid. 
     
     
         22 . A metal surface treatment liquid for cation electrodeposition coating according to  claim 14 , further comprising an oxidizing agent. 
     
     
         23 . A metal surface treatment liquid for cation electrodeposition coating according to  claim 14 , further containing nitric acid, wherein the concentration of said nitric acid is in the range of 100 ppm to 100000 ppm. 
     
     
         24 . A metal surface treatment liquid for cation electrodeposition coating according to  claim 14 , further comprising at least one ion selected from the group consisting of aluminum ions and indium ions. 
     
     
         25 . A metal surface treatment liquid for cation electrodeposition coating according to  claim 15 , further comprising at least one ion selected from the group consisting of aluminum ions and indium ions. 
     
     
         26 . A metal surface treatment liquid for cation electrodeposition coating according to  claim 16 , further comprising at least one ion selected from the group consisting of aluminum ions and indium ions. 
     
     
         27 . A metal surface treatment liquid for cation electrodeposition coating according to  claim 23 , further comprising at least one ion selected from the group consisting of aluminum ions and indium ions. 
     
     
         28 . A method of metal surface treatment comprising a step of subjecting a metal base material to a surface treatment with the metal surface treatment liquid for cation electrodeposition coating according to  claim 14 . 
     
     
         29 . A metal base material comprising a coating film formed by a surface treatment obtained by the method according to  claim 28 . 
     
     
         30 . A metal base material according to  claim 29 , wherein an element ratio of zirconium/tin on a mass basis in the coating film is in the range of 1/10 to 10/1. 
     
     
         31 . A method of cation electrodeposition coating comprising steps of:
 subjecting a metal base material to a surface treatment with the metal surface treatment liquid according to  claim 14 , and to washing with water; and   subjecting the surface treated metal base material to cation electrodeposition coating.   
     
     
         32 . A metal base material coated by the cation electrodeposition obtained with the method according to  claim 31 .