Repair agent and repair method for plated base, as well as plated base

Abstract

Disclosed is a repair agent for a plated base including a plating layer which is disposed on a surface of a metal base and which includes a metal with a stronger tendency to ionization than metal comprising the metal base, the repair agent including a phosphoric acid compound and a phosphonic acid compound.

What is claimed is: 
     
         1 . A repair agent for a plated base including a plating layer which is disposed on a surface of a metal base and which includes a metal with a stronger tendency to ionization than metal comprising the metal base,
 the repair agent comprising a phosphoric acid compound and a phosphonic acid compound.   
     
     
         2 . The repair agent of  claim 1 , wherein
 the plated base has a defect reaching to the metal base, and   the metal with a strong tendency to ionization, the phosphoric acid compound, and the phosphonic acid compound form a protective film on the surface of the metal base which is exposed where the plated base has the defect.   
     
     
         3 . The repair agent of  claim 1 , the repair agent further comprising:
 a compound including the metal with a strong tendency to ionization.   
     
     
         4 . The repair agent of  claim 3 , wherein
 the metal with a strong tendency to ionization included in the compound also contributes to formation of the protective film.   
     
     
         5 . The repair agent of  claim 3 , wherein
 the repair agent includes the compound including the metal with a strong tendency to ionization at 10 to 400 parts by weight with respect to the phosphoric acid compound and the phosphonic acid compound included in total at 100 parts by weight.   
     
     
         6 . The repair agent of  claim 1 , wherein
 the phosphoric acid compound is an inorganic phosphoric acid compound.   
     
     
         7 . The repair agent of  claim 6 , wherein
 the inorganic phosphoric acid compound is a compound of a phosphoric acid (H 3 PO 4 ), or a phosphate, or both.   
     
     
         8 . The repair agent of  claim 7 , wherein
 the phosphate is a salt of first phosphoric acid ions (H 2 PO 4   − ), second phosphoric acid ions (HPO 4   2− ), or third phosphoric acid ions (PO 4   3− ), and cations, and   the cations are one or more ions selected from a group consisting of monovalent metal ions, divalent metal ions, trivalent metal ions, and ammonium ions.   
     
     
         9 . The repair agent of  claim 1 , wherein
 the phosphonic acid compound is an organic phosphonic acid compound.   
     
     
         10 . The repair agent of  claim 9 , wherein
 the organic phosphonic acid compound is a compound of a nitrogen-containing phosphonic acid compound, or a salt of the nitrogen-containing phosphonic acid, or both.   
     
     
         11 . The repair agent of  claim 10 , wherein
 the nitrogen-containing phosphonic acid compound is an amine which includes a phosphonate group.   
     
     
         12 . The repair agent of  claim 1 , wherein
 the metal with a strong tendency to ionization is one or more metals selected from a group consisting of zinc, aluminum, and magnesium.   
     
     
         13 . The repair agent of  claim 1 , wherein
 the plating layer is a zinc plating layer.   
     
     
         14 . A method for repairing the plated base using the repair agent of  claim 1 . 
     
     
         15 . The method of  claim 14 , wherein
 the repair agent is already included in the plating layer, and   when the plated base suffers a defect reaching to the metal base, the metal with a strong tendency to ionization, the phosphoric acid compound, and the phosphonic acid compound which are included in the plating layer form a protective film on the surface of the metal base which is exposed where the plated base has the defect.   
     
     
         16 . The method of  claim 14 , wherein
 when the plated base suffers a defect reaching to the metal base, while an aqueous solution of the repair agent is brought into contact with the defect, the metal with a strong tendency to ionization included in the plating layer is effused onto the surface of the metal base which is exposed where the plated base has the defect, and the metal with a strong tendency to ionization, the phosphoric acid compound, and the phosphonic acid compound form a protective film on the surface of the metal base exposed.   
     
     
         17 . The method of  claim 16 , wherein
 the repair agent is brought into contact with the defect by applying the aqueous solution of the repair agent onto the defect, or by immersing the plated base which has the defect in the aqueous solution of the repair agent.   
     
     
         18 . A plated base comprising:
 a plating layer which is disposed on a surface of a metal base and which includes a metal with a stronger tendency to ionization than a metal included in the metal base and a repair agent, wherein   the repair agent includes a phosphoric acid compound and a phosphonic acid compound.   
     
     
         19 . The plated base of  claim 18 , wherein
 the repair agent further includes a compound which includes the metal with a strong tendency to ionization.   
     
     
         20 . The plated base of  claim 19 , wherein
 the plated base includes the compound including the metal with a strong tendency to ionization at 10 to 400 parts by weight with respect to the phosphoric acid compound and the phosphonic acid compound included in total at 100 parts by weight.