Surface-treated material, method for producing the surface-treated material, and component formed by using the surface-treated material

Abstract

A surface-treated material of the present disclosure has a conductive substrate, and a surface treatment film which includes at least one layer of metal layers and is formed on the conductive substrate. The surface treatment film is a plating film. The surface treatment film is formed on a whole surface or a part of the conductive substrate through a zinc-containing layer that contains zinc as a main component and has a thickness of 50 nm or less, or is formed on the conductive substrate without through the zinc-containing layer. The surface-treated material has a ratio of a contact area to a test area of 85% or more as measured according to a tape test method defined in JIS H 8504: 1999.

1 . A surface-treated material comprising a conductive substrate, and a surface treatment film which includes at least one layer of metal layers and is formed on the conductive substrate, wherein
 the surface treatment film is a wet plating film; is formed on a whole surface or a part of the conductive substrate through a zinc-containing layer that contains zinc as a main component and has a thickness of 50 nm or less, or is formed on the conductive substrate without through the zinc-containing layer; and a ratio of a contact area to a test area is 85% or more as measured according to a tape test method defined in JIS H 8504: 1999.   
     
     
         2 . A surface-treated material comprising a conductive substrate, and a surface treatment film which includes at least one layer of metal layers and is formed on the conductive substrate, wherein
 in cross-sectional observation of the surface-treated material, when portions between a portion of the conductive substrate and a portion of the surface treatment film are subjected to a line analysis with the use of STEM-EDX, and an obtained profile of detection intensity of each component of the surface-treated material is viewed, a maximum value of an intensity ratio of zinc to a main component of the surface treatment film is 1/4 or less, in a specific analysis range in which the intensity of the main component of the surface treatment film is equal to or higher than the intensity of the main component of the conductive substrate; and a ratio of a contact area to a test area is 85% or more as measured according to a tape test method defined in JIS H 8504: 1999.   
     
     
         3 . The surface-treated material according to  claim 1 , wherein the conductive substrate is aluminum or an aluminum alloy. 
     
     
         4 . The surface-treated material according to  claim 1 , wherein each of the metal layers forming the surface treatment film is formed of any one selected from the group consisting of nickel, a nickel alloy, cobalt, a cobalt alloy, copper, a copper alloy, tin, a tin alloy, silver, a silver alloy, gold, a gold alloy, platinum, a platinum alloy, rhodium, a rhodium alloy, ruthenium, a ruthenium alloy, iridium, an iridium alloy, palladium and a palladium alloy. 
     
     
         5 . The surface-treated material according to  claim 1 , wherein the surface treatment film comprises two or more metal layers. 
     
     
         6 . A method for producing a surface-treated material according to  claim 1 , comprising:
 a first surface activation treatment step of treating a surface of the conductive substrate, with the use of an activation treatment liquid that contains 10 to 500 mL/L of any one acid solution which is selected from among sulfuric acid, nitric acid, hydrochloric acid, hydrofluoric acid and phosphoric acid, and 0.1 to 500 g/L (in terms of metal content of nickel or cobalt) of nickel compounds which include nickel sulfate, nickel nitrate, nickel chloride and nickel sulfamate, or cobalt compounds which include cobalt sulfate, cobalt nitrate, cobalt chloride and cobalt sulfamate, at a treatment temperature of 20 to 60° C., at a current density of 0.5 to 20 A/dm 2 , and for a treatment time period of 1 to 300 seconds,   prior to forming the surface treatment film on the conductive substrate by a wet plating method.   
     
     
         7 . The method for producing the surface-treated material according to  claim 6 , further comprising:
 a second surface activation treatment step of temporarily forming a zinc-containing thick film layer having a thickness of 100 nm or more on the surface of the conductive substrate by a zinc substitution method, then dissolving the zinc-containing thick film layer in a range of 50 nm or more, and reducing the thickness to a range of 50 nm or less to form the zinc-containing layer, or completely removing the zinc-containing thick film layer,   prior to performing the first surface activation treatment step.   
     
     
         8 . A terminal formed with the use of the surface-treated material according to  claim 1 . 
     
     
         9 . A connector formed with the use of the surface-treated material according to  claim 1 . 
     
     
         10 . A bus bar formed with the use of the surface-treated material according to  claim 1 . 
     
     
         11 . A lead frame formed with the use of the surface-treated material according to  claim 1 . 
     
     
         12 . A medical member formed with the use of the surface-treated material according to  claim 1 . 
     
     
         13 . A shield case formed with the use of the surface-treated material according to  claim 1 . 
     
     
         14 . A coil formed with the use of the surface-treated material according to  claim 1 . 
     
     
         15 . A contact switch formed with the use of the surface-treated material according to  claim 1 . 
     
     
         16 . The surface-treated material according to  claim 2 , wherein the conductive substrate is aluminum or an aluminum alloy. 
     
     
         17 . The surface-treated material according to  claim 2 , wherein each of the metal layers forming the surface treatment film is formed of any one selected from the group consisting of nickel, a nickel alloy, cobalt, a cobalt alloy, copper, a copper alloy, tin, a tin alloy, silver, a silver alloy, gold, a gold alloy, platinum, a platinum alloy, rhodium, a rhodium alloy, ruthenium, a ruthenium alloy, iridium, an iridium alloy, palladium and a palladium alloy. 
     
     
         18 . The surface-treated material according to  claim 2 , wherein the surface treatment film comprises two or more metal layers. 
     
     
         19 . A method for producing a surface-treated material according to  claim 2 , comprising:
 a first surface activation treatment step of treating a surface of the conductive substrate, with the use of an activation treatment liquid that contains 10 to 500 mL/L of any one acid solution which is selected from among sulfuric acid, nitric acid, hydrochloric acid, hydrofluoric acid and phosphoric acid, and 0.1 to 500 g/L (in terms of metal content of nickel or cobalt) of nickel compounds which include nickel sulfate, nickel nitrate, nickel chloride and nickel sulfamate, or cobalt compounds which include cobalt sulfate, cobalt nitrate, cobalt chloride and cobalt sulfamate, at a treatment temperature of 20 to 60° C., at a current density of 0.5 to 20 A/dm 2 , and for a treatment time period of 1 to 300 seconds,   prior to forming the surface treatment film on the conductive substrate by a wet plating method.   
     
     
         20 . A terminal formed with the use of the surface-treated material according to  claim 2 .